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A renewed interest in data analytics and decision support systems in developing automated computer systems is facilitating the emergence of hybrid intelligent systems by combining artificial intelligence (AI) algorithms with classical modeling paradigms such as mechanistic modeling (HIMM) and agent-based models (iABM). Data analytics have evolved remarkably, and the scientific community may not yet fully grasp the power and limitations of some tools. Existing statistical assumptions might need to be re-assessed to provide a more thorough competitive advantage in animal production systems towards sustainability. This paper discussed the evolution of data analytics from a competitive advantage perspective within academia and illustrated the combination of different advanced technological systems in developing HIMM. The progress of analytical tools was divided into three stages: collect and respond, predict and prescribe, and smart learning and policy making, depending on the level of their sophistication (simple to complicated analysis). The collect and respond stage is responsible for ensuring the data is correct and free of influential data points, and it represents the data and information phases for which data are cataloged and organized. The predict and prescribe stage results in gained knowledge from the data and comprises most predictive modeling paradigms, and optimization and risk assessment tools are used to prescribe future decision-making opportunities. The third stage aims to apply the information obtained in the previous stages to foment knowledge and use it for rational decisions. This stage represents the pinnacle of acquired knowledge that leads to wisdom, and AI technology is intrinsic. Although still incipient, HIMM and iABM form the forthcoming stage of competitive advantage. HIMM may not increase our ability to understand the underlying mechanisms controlling the outcomes of a system, but it may increase the predictive ability of existing models by helping the analyst explain more of the data variation. The scientific community still has some issues to be resolved, including the lack of transparency and reporting of AI that might limit code reproducibility. It might be prudent for the scientific community to avoid the shiny object syndrome (i.e. AI) and look beyond the current knowledge to understand the mechanisms that might improve productivity and efficiency to lead agriculture towards sustainable and responsible achievements. [ABSTRACT FROM AUTHOR]

Macro- and microminerals are required for all physiological processes in beef cattle. When mineral deficiencies occur in pasture-based production systems, a multitude of deficiency symptoms may occur, and most often, these deficiencies result in hidden losses to include reduced production potential, reduced immunity, and reproductive failure. More severe deficiencies will result in specific deficiency symptoms, depending on the specific mineral deficiency. In pasture-based beef operations, specific deficiency symptoms are seldom observed. Forage mineral supply is highly variable and dependent on the forage type, stage of forage growth, and soil fertility. Grazing cattle mineral requirements change throughout the production cycle. With the variability of forage mineral supply and the changing mineral requirements, care must be taken when developing mineral supplementation programs for grazing cattle. The macrominerals function in nerve transmission, bone development, and metabolism and as electrolytes. These are Ca, P, Mg, Na, K, Cl, and S. The microminerals function in various areas of metabolism, immune responsiveness, reproductive efficiency, and many other functions. These minerals are Zn, Cu, Fe, I, Mn, Se, Mo, and Co. Of these macro- and microminerals, those that are important for supplementation to pasture-based cattle include Ca, P, Mg, Na, Cl, Zn, Cu, I, Mn, Se, and Co. However, the amounts to be supplemented will depend on the specific mineral requirements and the forage supply of the minerals. Consequently, the development of free-choice mineral supplementation programs is a moving target. Generally, this entangled mess is sorted by taking one mineral at a time into consideration. However, in doing so, one has to be cognizant of the many interactions that occur when changing intake of just 1 mineral in the supplement with respect to the amount supplied in the base forage. Often times, mineral nutrition problems of one or more minerals are created when trying to correct a deficiency of another mineral. This paper will address specific factors that are important to consider when developing and delivering mineral supplementation programs in pasture-based production systems in the Southeastern United States. [ABSTRACT FROM AUTHOR]

Inevitably, pigs will experience stressors that antagonize lean tissue accretion, appetite, and feed conversion. Depending on the production system and age of the pig, these stressors commonly include weaning transition, diet changes, vaccination, enteric and respiratory pathogen challenges, activation of the HPA axis, and social stress. Additionally, the morbidity and mortality that accompany these stressors may be exacerbated by the illegalization of sub-therapeutic antibiotic use for growth promotion (AGPs) by the Veterinary Feed Directive. However, morbidity and mortality may also be mitigated by diet ingredients via direct and indirect modes of action on gastrointestinal health and function. The gastrointestinal tract has the vital but conflicting functions of nutrient and water absorption, while simultaneously regulating host mucosal defenses against noxious luminal contents such as microorganisms and their toxins. This puts the gastrointestinal tract epithelium and splenic tissue at the front line of nutrition, growth, and health of the pig in the new age of antimicrobial resistance concerns. As part of the body's splanchnic tissues, the gastrointestinal tract is very metabolically active and has high utilization of luminal nutrients and energy. This utilization or "first pass metabolism" by intestinal epithelial and lamina propria cells can be a major determinant of the systemic or post-absorptive availability of glucose, essential and non-essential amino acids, and short and long chain fatty acids. This makes the gastrointestinal tract critically important to the growth and health of livestock and avian species. This paper will discuss the physiological impact of various stress challenges and nutrition on pig performance, gastrointestinal function and integrity. [ABSTRACT FROM AUTHOR]

Information about several papers discussed at the Triennial Lactation symposium "Nutrigenomics in dairy cows" held by American Society of Animal Science on the role of nutritional molecules on expression of gene and functions of protein on July 20, 2014, is presented. Topics discussed include use of nutrigenomics to improve dairy production, concepts related to systems biology, physiological changes during the disease mastitis in cattle, and omics technology to study nutrition of livestocks.

The replacement of fishmeal (FM) by insect meal (IM) in aquafeed formulation has been thoroughly studied lately, but little is known about their impact on nutrient metabolism of fish. This study evaluated the impact not only of partial but also total FM replacement by IM on intermediary metabolism of European sea bass (Dicentrarchus labrax). A fishmeal-based diet was used as a control (CTRL) and two other diets were formulated to include 20% and 40% of defatted Tenebrio molitor larvae meal (dTM), replacing 50% (TM50) and 100% (TM100) of fishmeal (FM), respectively. After a 16-week feeding trial, a multidisciplinary approach including assessment of histological, biochemical, molecular, and enzymatic parameters was adopted to investigate hepatic and plasmatic responses to the different dietary formulations. The results obtained demonstrated that dTM can be successfully used to replace 50% of FM in diets for European sea bass, without adversely affecting liver health or intermediary metabolism of nutrients. As for TM100, although no signs of steatosis were observed in the liver, the activity of glycolytic and lipogenic genes and enzymes increased when compared to CTRL diet (P < 0.05), resulting in higher levels of plasmatic non-esterified fatty acids and triacylglycerides (P < 0.05), which in the long-term may compromise fish health, thus precluding such a high degree of substitution for use in practical diets for European sea bass. [ABSTRACT FROM AUTHOR]

Medium chain fatty acids (MCFA) are six to twelve carbon length molecules with significant promise as mitigants of biological hazards in feed and feed ingredients. Residual mitigation activity allows for post-processing contamination control and prevention. However, duration of mitigation activity has not been established. Therefore, the objective of this experiment was to characterize the mitigation properties of MCFA-treated swine feed when inoculated 40 d (June to July 2017) following feed manufacture. Treatments (n=8) consisted of a dose response including 0, 0.25, 0.50, 1.0, and 1.5% dietary addition of a MCFA blend (1:1:1 ratio C6, C8, and C10) as well as 0.50% C6, 0.50% C8, or 0.50% C10 alone. Diets were stored in paper bags at barn temperature and humidity for 40 d following manufacture. Feed was then sampled and inoculated (3 replicates/treatment×day combination) with PEDV for a final titer of 104 TCID50/g. Samples were analyzed on d 0 and 3 after inoculation using qRT-PCR and a linear mixed model (PROC GLIMMIX; SAS Institute, Inc., Cary, NC) was used with individual bottle as the experimental unit. Samples with a lower cycle threshold (Ct) indicate a greater quantity of detectible virus. A significant treatment×day interaction (P<0.001) was observed, where Ct increased over time in some treatments and was reduced in others. When evaluating increasing inclusion of MCFA blend, an inclusion level × day interaction was observed (quadratic, P=0.023). This was because PEDV Ct values increased in a quadratic manner (P=0.001) on d 0 and a linear (P<0.001) manner on d 3 with increasing MCFA blend diet concentrations. On d 0 after inoculation, the addition of C6, C8, or C10 alone resulted in greater Ct values compared to no supplemented MCFA (P<0.05; Ct=29.7, 30.0, 28.7, 27.1, for the C6, C8, C10, control, respectively). There was no evidence that the addition of 0.50% C6 and 0.50% C8 influenced Ct value (P>0.05) compared to the 0.50% MCFA blend; however, adding 0.50% C10 resulted in a lower (P<0.05) Ct value (28.7 vs 30.9) compared to the 0.50% MCFA blend. On d 3 after inoculation, the addition of 0.50% C6 or 0.50% C10 resulted in greater Ct values compared to control diet (P<0.05), whereas, no evidence of improvement was observed in the 0.50% C8 diet compared to control (P>0.05). In summary, inclusion of MCFA in feed reduces detection of PEDV even after a significant time period following feed manufacturing. Further assessment of MCFA viral infectivity is warranted. [ABSTRACT FROM AUTHOR]

Modern animal scientists, industry, and managers have never faced a more complex world. Precision livestock technologies have altered management in confined operations to meet production, environmental, and consumer goals. Applications of precision technologies have been limited in extensive systems such as rangelands due to lack of infrastructure, electrical power, communication, and durability. However, advancements in technology have helped to overcome many of these challenges. Investment in precision technologies is growing within the livestock sector, requiring the need to assess opportunities and challenges associated with implementation to enhance livestock production systems. In this review, precision livestock farming and digital livestock farming are explained in the context of a logical and iterative five-step process to successfully integrate precision livestock measurement and management tools, emphasizing the need for precision system models (PSM s). This five-step process acts as a guide to realize anticipated benefits from precision technologies and avoid unintended consequences. Consequently, the synthesis of precision livestock and modeling examples and key case studies help highlight past challenges and current opportunities within confined and extensive systems. Successfully developing PSM requires appropriate model(s) selection that aligns with desired management goals and precision technology capabilities. Therefore, it is imperative to consider the entire system to ensure that precision technology integration achieves desired goals while remaining economically and managerially sustainable. Achieving long-term success using precision technology requires the next generation of animal scientists to obtain additional skills to keep up with the rapid pace of technology innovation. Building workforce capacity and synergistic relationships between research, industry, and managers will be critical. As the process of precision technology adoption continues in more challenging and harsh, extensive systems, it is likely that confined operations will benefit from required advances in precision technology and PSMs, ultimately strengthening the benefits from precision technology to achieve short- and long-term goals. [ABSTRACT FROM AUTHOR]

The field of animal science, and especially animal nutrition, relies heavily on modeling to accomplish its day-to-day objectives. New data streams ("big data") and the exponential increase in computing power have allowed the appearance of "new" modeling methodologies, under the umbrella of artificial intelligence (AI). However, many of these modeling methodologies have been around for decades. According to Gartner, technological innovation follows five distinct phases: technology trigger, peak of inflated expectations, trough of disillusionment, slope of enlightenment, and plateau of productivity. The appearance of AI certainly elicited much hype within agriculture leading to overpromised plug-and-play solutions in a field heavily dependent on custom solutions. The threat of failure can become real when advertising a disruptive innovation as sustainable. This does not mean that we need to abandon AI models. What is most necessary is to demystify the field and place a lesser emphasis on the technology and more on business application. As AI becomes increasingly more powerful and applications start to diverge, new research fields are introduced, and opportunities arise to combine "old" and "new" modeling technologies into hybrids. However, sustainable application is still many years away, and companies and universities alike do well to remain at the forefront. This requires investment in hardware, software, and analytical talent. It also requires a strong connection to the outside world to test, that which does, and does not work in practice and a close view of when the field of agriculture is ready to take its next big steps. Other research fields, such as engineering and automotive, have shown that the application power of AI can be far reaching but only if a realistic view of models as whole is maintained. In this review, we share our view on the current and future limitations of modeling and potential next steps for modelers in the animal sciences. First, we discuss the inherent dependencies and limitations of modeling as a human process. Then, we highlight how models, fueled by AI, can play an enhanced sustainable role in the animal sciences ecosystem. Lastly, we provide recommendations for future animal scientists on how to support themselves, the farmers, and their field, considering the opportunities and challenges the technological innovation brings. [ABSTRACT FROM AUTHOR]

It was hypothesized that hybrid rye may replace corn in diets for growing and finishing pigs without impacting growth performance, carcass characteristics, or meat quality. A total of 128 pigs (23.69 ± 2.51 kg) were allotted to 4 treatments with 8 replicate pens per treatment. Phase 1 and 2 diets were fed for 35 d each and phase 3 diets were fed for 27 d. Within each phase, pigs were fed a control corn and soybean meal diet or a diet in which 33, 66, or 100% of the corn in the control diet was replaced with hybrid rye. Average daily gain (ADG) and average daily feed intake (ADFI) decreased (linear, P < 0.05) in phase 1 with increased dietary inclusion of hybrid rye. In phase 3, gain:feed (G:F) increased and then decreased (quadratic, P < 0.05) with more hybrid rye in the diet. Overall ADG, ADFI, and G:F did not differ among treatments. Diet did not impact most carcass traits, but loin (visual) and backfat (instrumental L*) color were paler (linear, P < 0.05) with greater inclusion of hybrid rye in the diet. Organ weights increased (linear, P < 0.05) with increased dietary hybrid rye. In conclusion, pigs fed hybrid rye consumed less feed in phase 1, resulting in reduced ADG, but growth performance for the entire growing-finishing period did not differ among treatments. Hybrid rye may replace all the corn in growing and finishing pig diets without diminishing growth performance or carcass quality, but feed intake may be reduced at high inclusion rates. [ABSTRACT FROM AUTHOR]

The objective of this project was to determine the impact of feeding growing pigs with high wheat millrun diets supplemented with a multi-carbohydrase enzyme (amylase, cellulase, glucanase, xylanase, and invertase activities) on nutrient digestibility, growth performance, and greenhouse gas (GHG) output (carbon dioxide, CO2; nitrous oxide, N2O; methane, CH4). Three experiments were conducted utilizing six treatments arranged as a 3 × 2 factorial (0%, 15%, or 30% wheat millrun; with or without enzyme) for the digestibility experiment or as a 2 × 2 factorial (0% or 30% wheat millrun; with or without enzyme) for the performance and GHG experiments. The digestibility, performance, and GHG experiments utilized 48 individually housed pigs, 180 pigs housed 5 per pen, or 96 pigs housed 6 per chamber, respectively. Increasing wheat millrun up to 30% in the diet of growing pigs resulted in decreased energy, nitrogen (N) and phosphorus (P) apparent total tract digestibility and net energy content (P < 0.01). Overall, average daily gain (ADG) and gain to feed ratio were reduced in pigs fed wheat millrun (P < 0.05). Enzyme supplementation had minimal effects on the digestibility or performance parameters measured. Feeding diets with 30% millrun did not affect GHG output (CH4: 4.7 and 4.9; N2O: 0.45 and 0.42; CO2: 1,610 and 1,711 mg/s without or with millrun inclusion, respectively; P > 0.78). Enzyme supplementation had no effect on GHG emissions (CH4: 4.5 and 5.1; N2O: 0.46 and 0.42; CO2: 1,808 and 1,513 mg/s without or with enzymes, respectively; P > 0.51). Overall, the carbohydrase enzyme had minimal effects on parameters measured, regardless of wheat millrun inclusion (P > 0.10). Although energy, N and P digestibility, and ADG were reduced, the inclusion of up to 30% wheat millrun in the diet has no effect on GHG emissions from growing pigs (P > 0.10). [ABSTRACT FROM AUTHOR]

This paper presents a novel find that the feed enzyme xylanase (XYL) improves pig viability. Xylanases break down cell wall arabinoxylans to shorter chain xylo-oligomers and these become a food source for beneficial gut microflora. In poultry, an increase in this substrate coincided with a balance shift toward more beneficial microflora. This is hypothesized to support intestinal barrier function and improved host health. A total of 2124 PIC castrate and female pigs (11.7 ± 0.2 kg) were used in a growth assay to approx. 137.9 kg (± 0.5 kg). Pigs were placed in a commercial research facility, blocked by gender and genotype, stratified by weight and allocated (34 pigs/pen, 0.70 mVpig) to diets with 0, 0.075, 0.150 or 0.225 g Danisco Xylanase/kg feed. Treatments were arranged as a 2 x 4 x 3 factorial (sex, diet, genotype) with pen being the experimental unit. Diets were composed of corn, soybean meal, cornDDGS (15.0%), wheat midds (10%) and soy oil (1.0%). Nutrient levels met or exceeded the requirement (PIC 2008). Early nursery diets were medicated, however diets were maintained medication free after 30 kg body weight. Pay lean® (Elanco) was used at 5 and 10 mg/kg in the final 2 diets. Pigs were classified as moderately high health based onPRRS and PEDv negative status. Mortality and removal rate, for medical treatment, from 12 kg to harvest was 4.16%. Under these conditions, increasing XYL dose tended to reduce mortality (3.99, 3.51, 2.25, 2.39%, SEM = 0.98, linear P = 0.175). Death loss for pigs that remained in test pens (excluded medical pens) averaged 3.39, 2.32, 1.90, 1.62%, SEM = 0.82, linear P = 0.126). Carcass ADG and G:F ratio was computed as the difference between estimated initial carcass weight (0.74 x BW) and plant carcass weight. Carcass ADG was not improved but carcass FCR improved as XYL increased (0.286, 0.287, 0.291, 0.290, P = 0.012, SEM = 0.0015). This occurred, despite no improvement in whole-body G:F ratio, because carcass yield tended to improve with dose: 73.9,74.0, 74.1, 74.3% (P = 0.160 linear). When gain was expressed on a pen basis (viable pigs x gain), whole-body and carcass gain improved in a linear manner (P = 0.071, P = 0.047); the latter averaged 2892, 2926, 3104, 3035 kg/pen (SEM, 66.4). This study is the first to show that the feed enzyme XYL improves pig viability and in a dose related manner; even under high health conditions and for progeny of 3 genotypes (line x trt, P > 0.50). This outcome has implications for animal well-being and reduced enteric antibiotic use. [ABSTRACT FROM AUTHOR]

A 300-d study evaluated the stability of 4 phytase products stored under varied environmental conditions. The 4 products were: 1) Quantum Blue 5G (AB Vista, Marlborough United Kingdom); 2) Ronozyme HiPhos GT 2700 (DSM Nutritional Products, Parsippany, NJ); 3) Axtra Phy TPT (Dupont, Wilmington, DE); and 4) Microtech 5000 Plus (Guangdong VTR Bio-Tech Co., Ltd., Guangdong, China). Products were stored as pure forms at -20, 4, 22, or 35°C (75% humidity), or in a vitamin or vitamin trace mineral (VTM) premix at 22 and 35°C (75% humidity). Samples were stored in paper bags and sampled on d 30, 60, 90, 120, 210, and 300. Stability was determined as amount of residual phytase activity (% of initial). For pure forms, all interactive and main effects of product, time, and temperature were significant (P < 0.05). From d 30 to 300, products had similar reductions in phytase activity at the 3 highest temperatures; however, Quantum Blue 5G, Ronozyme HiPhos GT 2700, and Axtra Phy TPT had reduced (P < 0.05) phytase activity compared to Microtech 5000 Plus at -20°C. As storage time increased, residual phytase activity was reduced (P < 0.05) regardless of product and storage temperature. Also, when product was stored at 4 and 22°C, phytase activity was improved compared to -20 and 35°C For vitamin and VTM premixes, a timextemperature x product interaction (P < 0.05) was observed as a result of, Axtra Phy TPT and Microtech 5000 Plus having reduced residual phytase activity (P < 0.05) compared to the other 2 products when stored at 22°C, while activity of Axtra Phy TPT was reduced (P < 0.05) even further than the other 3 products when stored at 35°C regardless of form. From d 30 to 300, Axtra Phy TPT and Microtech 5000 Plus had the lowest (P < 0.05) residual phytase activity compared to the other 2 products. The VTM had decreased (P < 0.05) residual phytase activity compared to the pure product and vitamin premixes. In conclusion, phytase stored for longer than 90-120 d at 35°C or -20°C in pure form, or when stored as a VTM premix had reduced residual phytase activity. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the influence of biochar obtained from exothermic production of lodgepole pine (Pinus contorta) and quaking aspen (Populus tremuloides) on sheep performance and diet digestibility and on preference for a ration enriched with this carbon-based material. Twenty-four lambs were housed in individual pens and assigned to one of three treatment groups (eight animals per group), where they received: 1) a 60:40 ration of alfalfa:barley (Control), 2) an isoenergetic and isonitrogenous ration with alfalfa, barley, and 2% biochar (BC), and 3) a simultaneous offer of the Control and BC rations (Choice). Lambs were exposed to two consecutive feeding periods (Period 1: 13 d and Period 2: 21 d), representing time intervals where the evolution of intake, animal performance, and rumen parameters were assessed; in vivo digestibility was determined during the last 5 d of the study. Ration intake did not differ among groups of lambs (P > 0.10), although during some days in Period 2, intake was greater for the BC and Choice groups than for the Control group (P < 0.05). Lambs in Choice had a lower preference for BC than for the Control ration (Period 1: P < 0.05; Period 2: P < 0.10), although they incorporated a substantial amount of BC (39 and 40%, for Periods 1 and 2, respectively) into their diets. No differences in body weight gains (ADG) or gain-to-feed ratios were found among groups of animals (P > 0.10), although dry matter digestibility and digestible dry matter intake was greater for lambs in the BC group than for lambs in Control group (P < 0.05). The ruminal concentration of the volatile acid acetate in Period 2 was greater for BC than for Choice (P < 0.05). During the same period, the concentration of valerate and ruminal pH values were greater in BC than in Control (P < 0.05). Thus, the addition of biochar to grain-based diets enhanced diet digestibility and influenced some ruminal parameters in lambs. Nevertheless, these positive effects were not reflected in significant improvements on ADG or feed conversion efficiencies. Lambs offered choices between Control and BC rations formed a diet with concentrations of biochar of ~1.2%, suggesting that these animals would tolerate such levels without reductions in ration palatability. [ABSTRACT FROM AUTHOR]

The announces 2017 Southern Section Awards including Distinguished Service Award to L. Wayne Greene for nutrition research; Emerging Scholar Award to W. Brandon Smith for pastures; and Outstanding Young Animal Scientist Award to Ranjith Ramanathan for food science and research in beef quality.

Two experiments were conducted to investigate the effect of inclusion level of corn germ meal (CGM) on the DE and ME values of CGM and to evaluate the ileal AA digestibility of CGM fed to growing pigs. In Exp. 1, 42 barrows (63.8 ± 2.1 kg BW) were allotted to seven diets in a completely randomized design with six replicates per diet. Diets included a corn–soybean meal (SBM) diet and six additional diets containing 4.85%, 9.70%, 19.40%, 29.10%, 38.80%, or 48.50% CGM. Pigs were fed twice daily, at 0730 and 1630 hours, at a level of 4% of BW, and feces and urine were collected for 5 d. The apparent total tract digestibility (ATTD) of DM, OM, CP, acid-hydrolyzed ether extract, and the DE and ME in diets linearly decreased (P < 0.01) as dietary CGM increased. Inclusion level of CGM had no effect on the DE and ME values of CGM. On a DM basis, the concentration of DE and ME varied from 3,396 to 3,747 kcal/kg and 3,107 to 3,502 kcal/kg, respectively. In Exp. 2, 11 crossbred barrows (30.4 ± 2.9 kg BW) with a T-cannula in the distal ileum were allotted to an 11 × 6 Youden square design with 11 diets and 6 period, which included an N-free diet and 10 CGM test diets. Chromic oxide (0.3%) was included in all diets as an indigestible marker. Pigs were fed daily at 4% of BW during each period, which consisted of 5 d of diet adaptation followed by 2 d of digesta collection. The apparent ileal digestibility (AID) of Ile, Thr, and Ala and the standardized ileal digestibility (SID) of CP and Ile varied (P < 0.01) among the 10 CGM. The AID of CP and all AA except Pro and Tyr, and the SID of all AA except Pro were the greatest (P < 0.05) in sample 7. The AID and SID of CP averaged 40.47% and 64.75%, respectively, and varied from 32.30% to 54.87% and from 57.48% to 72.15%, respectively. The average SID of Lys, Met, Thr, and Trp was 65.61%, 76.15%, 65.29%, and 60.17%, respectively, with a SEM of 4.49, 2.40, 5.95, and 6.82, respectively. The average SID of Pro was 101.76%, with an SEM of 17.26. Increasing dietary CGM decreased the ATTD of nutrients, the DE and ME values of diets but CGM. The AID and SID of AA in CGM are low but source dependent, and CGM may be fed to pigs as an protein-rich feedstuff. [ABSTRACT FROM AUTHOR]

Microbial phytase is widely used to enhance digestibility of phytate-P. By tradition, diets with P content well below requirement are used to quantify phytate-P release by phytase, but P-adequate diets may be more physiologically relevant. The objective of this study was to investigate the effects of phytase on P digestion and metabolism and develop a P release curve for phytase in P-adequate diets (above requirement according to NRC, 2012), and to compare these effects in a P-deficient diet. Three replicates of 24 barrows each (BW = 23.0 ± 1.8 kg) were randomly assigned to 1 of 8 dietary treatments, housed in individual pens for 21 d, then moved to metabolism crates for 5 d urine and fecal collections. A basal corn-soybean meal diet (P-adequate, A) was formulated at 0.36% standardized total tract digestible (STTD) P and total Ca:STTD P of 1.83. Phytase was added to A at 200 (A200), 400 (A400), 600 (A600), and 800 (A800) phytase units (FTU)/kg. A positive control diet (PC) was formulated using monocalcium phosphate (MCP) to increase STTD P by 0.16% to 0.52%, the expected STTD P release of 800 FTU/kg. A P-deficient diet (D) was formulated by reducing MCP to achieve 0.21% STTD P, and 200 FTU phytase/kg was added to D for D200. Pig was the experimental unit, and replicate and dietary treatment were fixed effects. Orthogonal polynomial contrasts were used to test linear and quadratic effects of phytase within A, A200, A400, A600, and A800. Phytase increased percent apparent total tract digestibility (ATTD) and STTD of P (quadratic P < 0.001), and quantity of absorbed P (linear P < 0.001; quadratic P = 0.069). Urinary P increased linearly with phytase (P < 0.001) and retained P also increased (linear P = 0.001, quadratic P = 0.094). Phytate-P release was estimated to be 0.049, 0.080, 0.093, and 0.09% STTD P for 200, 400, 600, and 800 FTU/kg, respectively. It appears that the effect of phytase may be lower in P-adequate diets as compared to P-deficient diets, given that there was a 12% improvement for A200 versus A, and a 28% improvement in STTD P for D200 versus D. In conclusion, phytase improved P digestibility and retention in P-adequate diets, and P digestibility was used to estimate the quantity of P released by phytase. Further research investigating P release by phytase in P-adequate diets, rather than P-deficient diets, may be preferable. [ABSTRACT FROM AUTHOR]

The central aim of this meta-analysis was to determine whether the rumen microbiome can serve as an accurate predictor of performance in beef and dairy cattle compared with predictions based on diet composition. To support this comparison, a set of models was derived and compared. Models predicted milk yield (MY), average daily gain (ADG), dry matter intake (DMI), dairy feed efficiency (FE), and beef FE using different sets of independent variables: diet (D), microbial (M), and experimental (E). Diet variables included dry matter, organic matter, neutral detergent fiber, acid detergent fiber, crude protein, ether extract, nonfiber carbohydrate, starch, and forage percentages. Microbiome variables included relative abundance of 3 major rumen bacterial phyla, species richness, and species diversity. Experimental variables included publication year, breed type (dairy, beef, or Bos indicus), and rumen sampling fraction (fluid or solid). A second set of models used D and E variables as predictors for the microbiome. For both the production and microbiome model sets, predictor variable sets were used individually and in combination. Linear mixed-effects regression, weighted by 1/standard error of the mean, was used to derive models using data from 51 peer-reviewed publications. Models for the same response variable were compared on the basis of concordance correlation coefficient with study effects removed (uCCC), root-estimated variance associated with study and error, and corrected Akaike information criterion values, wherever appropriate. The MY model using D + M + E predictors outperformed all other MY models (uCCC = 0.71). ADG was most accurately predicted by D alone (uCCC = 0.92). Interestingly, M + E was more successful at predicting DMI than any model using D variables. Similarly, dairy FE was more accurately predicted by M + E than D, albeit only slightly (uCCC = 0.69 vs. 0.65). Beef FE could only be modeled using D variables. Overall, breed type proved a better predictor of relative abundances of most rumen bacterial phyla than D. Conversely, species richness and diversity indicators were unaffected by breed type, but could be predicted by D with moderate precision and accuracy (uCCC = 0.63 to 0.69). This analysis suggests that diet and the microbiome may exert independent effects on various aspects of performance. Further research is necessary to determine the reasons for these independent influences. [ABSTRACT FROM AUTHOR]

Active plant metabolites (APM) are recognized as modifiers of ruminal microbial fermentation including methanogenesis and biohydrogenation of fatty acids (FA). Coleus amboinicus Lour. leaves (CAL) are rich in several APM, which could serve as ruminal fermentation modulators. A phytochemical analysis showed that CAL contain phenolic acids (10.4 mg.g.1 dry matter [DM]; high in rosmarinic acid), flavonoids (2.6 mg.g.1 DM), diterpenes (2 mg.g.1 DM), and linolenic acid (35.4 g (100 g).1 FA). This study aimed to investigate the effect of CAL on ruminal methanogenesis and biohydrogenation as well as basic fermentation characteristics and microbial populations. The in vitro experiment was carried out using Hohenheim gas test system with 40 mL of buffered ruminal fluid incubated for 24 h at 39 °C in anaerobic conditions. Approximately 400 mg (DM basis) of total mixed ration (TMR) was used as a control substrate and the CAL substrate was used at doses of 10, 20, 40, and 80 mg DM replacing equal amounts of TMR. Addition of CAL decreased methane production up to 30% linearly as the amount of CAL increased (P < 0.05). In vitro dry matter digestibility and ammonia tended to increase with increasing doses of CAL. Concentration of total volatile fatty acids was not affected by the CAL although there appeared to be a minor positive linear trend; however, acetate, butyrate, and isobutyrate proportion increased quadratically (P < 0.001). CAL tended to linearly increase á-linolenic acid and conjugated linoleic acid as well as increased stearic acid concentration in buffered ruminal fluid. CAL particularly increased total protozoa and bacterial populations during fermentation, but inhibited methanogens. It is concluded that the CAL may be promising to be used as a feed additive to decrease methanogenesis as well as biohydrogenation of FA in the rumen. [ABSTRACT FROM AUTHOR]

Work was conducted to test the hypothesis that the nutritional composition of bakery meal varies depending on where in the United States the meal is produced due to different raw materials being used in the production of the meals. Forty-six samples of bakery meal were collected from feed mills located in the swine producing states in the United States. Based on the state where samples were collected, they were grouped into 5 regions: 1) AL, DE, GA, NC, PA, and VA (10 samples); 2) CO, MO, OK, and TX (10 samples); 3) IN, KY, OH, and TN (8 samples); 4) IA (11 samples); and 5) MN (7 samples). All samples were analyzed for proximate components, GE, AA, carbohydrates, and minerals, and IVDMD and in vitro energy digestibility (IVGED) were also determined. Results indicated that the average concentration of DM was (91.84 ± 1.29%) and there was no difference among regions. The concentration of ash in bakery meal from MN was greater (P < 0.05) than in meals from other regions, but for all other proximate components, no differences among sources were observed. The average concentration (DM basis) of CP (12.20 ± 2.16%), acid hydrolyzed ether extract (AEE, 9.38 ± 1.95%), starch (44.61 ± 5.47%), and NDF (13.77 ± 4.23%) indicated that bakery meal consists of a mixture of food ingredients originating from flour or whole cereal grains and with some high-fiber ingredients such as brans or canola coproducts also included. It also appears that oil or fats were added during production. With the exception of His, no differences among regions were observed for indispensable AA and the average concentrations (DM basis) of Lys, Met, Thr, and Trp were 0.35 ± 0.08%, 0.19 ± 0.03%, 0.38 ± 0.06%, and 0.13 ± 0.03%, respectively. The bakery meals from MN contained more (P < 0.05) Ca than bakery meals from other regions, indicating that limestone may have been added to bakery meal from MN to improve flowability. However, bakery meals from MN and IA contained less (P < 0.05) total P, phytate, and phytate-bound P than bakery meals produced in the states east of the Mississippi River. There were, however, no differences in IVDMD (79.06 ± 6.62%) or of IVGED (74.84 ± 8.20%) of bakery meals among regions. The present results indicate that variations in the chemical composition of bakery meal obtained from different regions in the United States are relatively small and likely without great impact on the nutritional value of the meals, but in vivo digestibility experiments are needed to confirm this hypothesis. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of pre and/or postnatal supplementation of a dry whole cell algae (DHA-Gold) to goat kids, on in vitro methane (CH4) production, animal growth, and rumen morphology at the age of 6 mo. Furthermore, the in vitro retreatment effect of DHA-Gold was evaluated. Twenty pregnant Saanen goats giving birth to 2 male kids were used. Half of these does were supplemented (D+) with 18.2 g/d of DHA-Gold in the last 3 wk of pregnancy, whereas the other half was not (D-). After kidding, one goat kid per doe in both groups was supplemented daily with 0.28 g/kg of body weight of DHA-Gold (k+) until 12 wk, whereas the other goat kids were untreated (k-). This resulted in 4 experimental groups D+k+, D+k-, D-k+, and D-k-. In vitro incubations were performed at the ages of 4 wk, 11 wk, and 6 mo. At the age of 6 mo, goat kids were euthanized and additional incubations were performed supplementing 4 doses of DHA-Gold (0, 0.4, 0.8, and 1.6 mg/mL). Additionally, rumen tissue of the atrium ruminis, ventral rumen, and dorsal blind sac were collected to assess rumen morphology. Rumen inocula of 4-wk-old goat kids supplemented D+ showed lower (P < 0.05) in vitro CH4 production, however, this was mainly due to a reduction in the overall fermentation, while CH4 expressed relatively to total volatile fatty acids (VFA) was higher when goat kids were treated D+ or k+. The detrimental D+ effect on VFA production diminished at 11 wk old but remained a tendency (0.05 < P < 0.1). As for 4 wk D+ as well as k+ supplementation of DHA-Gold stimulated rather than inhibited in vitro CH4 production expressed relative to total VFA. Supplementation of DHA-Gold either D+ or k+ decreased density, width, and surface area of the ruminal papillae. However, no effect on animal growth was observed. Moreover, detrimental effects of D+ or k+ treatment on VFA production or stimulation of relative CH4 production were no longer observed at 6 mo old. Nevertheless, direct exposure of DHA-Gold to 6-mo-old inoculum linearly (P < 0.05) decreased CH4 and VFA production, which tended (P = 0.06) to be greater when using D-rumen inoculum. Accordingly, neither D+ nor k+ DHA-Gold supplementation showed potential for reduction of rumen methanogenesis. Furthermore, this early life intervention could represent some risk for impaired rumen papillae development, which, however, did not impair animal performance. [ABSTRACT FROM AUTHOR]

A biography of professor Dr. (doctor) Cornelis Franciscus Maria de Lange is presented. He was born on on April 19, 1961 in De Weere, the Netherlands. It informs on education in animal science, and animal nutrition. He was married to Deirdre “Dede" Conway with four children. It also reports on Lange being as a highly prolific scientist, his manuscripts and research accomplishments.

Six ruminally cannulated cows (570 ± 73 kg) fed corn residues were placed in a 6 × 6 Latin square to evaluate predictions of diet composition from ruminally collected diet samples. After complete ruminal evacuation, cows were fed 1-kg meals (dry matter [DM]-basis) containing different combinations of cornstalk and leaf and husk (LH) residues in ratios of 0:100, 20:80, 40:60, 60:40, 80:20, and 100:0. Diet samples from each meal were collected by removal of ruminal contents after 1-h and were either unrinsed, hand-rinsed or machine-rinsed to evaluate effects of endogenous compounds on predictions of diet composition. Diet samples were analyzed for neutral (NDF) and acid (ADF) detergent fiber, acid detergent insoluble ash (ADIA), acid detergent lignin (ADL), crude protein (CP), and near infrared reflectance spectroscopy (NIRS) to calculate diet composition. Rinsing type increased NDF and ADF content and decreased ADIA and CP content of diet samples (P < 0.01). Rinsing tended to increase (P < 0.06) ADL content of diet samples. Differences in concentration between cornstalk and LH residues within each chemical component were standardized by calculating a coefficient of variation (CV). Accuracy and precision of estimates of diet composition were analyzed by regressing predicted diet composition and known diet composition. Predictions of diet composition were improved by increasing differences in concentration of chemical components between cornstalk and LH residues up to a CV of 22.6 ± 5.4%. Predictions of diet composition from unrinsed ADIA and machine-rinsed NIRS had the greatest accuracy (slope = 0.98 and 0.95, respectively) and large coefficients of determination (r2 = 0.86 and 0.74, respectively). Subsequently, a field study (Exp. 2) was performed to evaluate predictions of diet composition in cattle (646 ± 89 kg) grazing corn residue. Five cows were placed in 1 of 10 paddocks and allowed to graze continuously or to strip-graze corn residues. Predictions of diet composition from ADIA, ADL, and NIRS did not differ (P = 0.99), and estimates of cornstalk intake tended to be greater (P = 0.09) in strip-grazed compared to continuously grazed cows. These data indicate that diet composition can be predicted by chemical components or NIRS by ruminal collection of diet samples among cattle grazing corn residues. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine whether the combination of dietary soluble fiber and cellobiose exerts a synergistic effect on growth performance, health status, fermentation traits, and immune response in rabbits. Six treatments in a 3 × 2 factorial arrangement were used: 3 cellobiose concentrations in drinking water (0.0, 7.5, and 15.0 g/L) × 2 dietary levels of soluble fiber (84.0 and 130 g/kg DM, for the low soluble fiber [LSF] and high soluble fiber [HSF] diets, respectively). A total of 318 young rabbits (53/treatment) were weaned at 34 d of age and had ad libitum access to feed and water. At 46 d of age, 9 rabbits/treatment were slaughtered and ileal and cecal digesta were collected to analyze VFA profile and the immune response in the cecal appendix mucosa. At 48 d of age, the cellobiose supplementation was withdrawn and the experimental diets were replaced by a standard commercial diet until 61 d of age. From 34 to 48 d of age, there was a linear increase of mortality with the level of cellobiose in the HSF group (0% vs. 17.1%; P = 0.017). In contrast, a quadratic effect of cellobiose level on mortality was observed in the LSF group, the rabbits offered 7.5-cellobiose showing the lowest mortality (5.7% vs. 21.4%; P = 0.030). Cellobiose level had a quadratic effect on ADFI, ADG, and G:F in this period (P = 0.047), with the 7.5-cellobiose groups having the best growth performance. In contrast, only minor changes on these traits were observed from 48 d of age onwards. Cellobiose level influenced quadratically the ileal VFA concentrations (P = 0.014), showing the maximal value in the 7.5-cellobiose groups. In rabbits fed 7.5-cellobiose-LSF, a change of acetate to propionate, butyrate, and valerate was observed in the ileum. Increasing cellobiose levels reduced linearly cecal VFA concentrations in HSF fed rabbits, but no effect was detected in LSF groups (P = 0.046). The level of soluble fiber increased VFA concentrations in both the ileum (by 22%; P < 0.001), and the cecum (by 11%; P = 0.005). The relative gene expression of IL-6, IL-10, TNF-a, iNOS, MUC-1, and toll-like receptors (TLR-2 and TLR-4) in the cecal appendix increased linear and quadratically with increasing levels of cellobiose (P = 0.063). In conclusion, in rabbits fed LSF diets, a dose of 7.5 g cellobiose/L drinking water would be recommended, whereas these levels of cellobiose supplementation should be avoided in rabbits fed HSF diets. [ABSTRACT FROM AUTHOR]

Evaluation of the body chemical composition of beef cattle can only be measured postmortem and those data cannot be used in real production scenarios to adjust nutritional plans. The objective of this study was to develop multiple linear regression equations from in vivo measurements, such as ultrasound parameters [backfat thickness (uBFT, mm), rump fat thickness (uRF, mm), and ribeye area (uLMA, cm2)], shrunk body weight (SBW, kg), age (AG, d), hip height (HH, m), as well as from postmortem measurements (composition of the 9th to 11th rib section) to predict the empty body and carcass chemical composition for Nellore cattle. Thirty-three young bulls were used (339 ± 36.15 kg and 448 ± 17.78 d for initial weight and age, respectively). Empty body chemical composition (protein, fat, water, and ash in kg) was obtained by combining noncarcass and carcass components. Data were analyzed using the PROC REG procedure of SAS software. Mallows' Cp values were close to the ideal value of number of independent variables in the prediction equations plus one. Equations to predict chemical components of both empty body and carcass using in vivo measurements presented higher R2 values than those determined by postmortem measurements. Chemical composition of the empty body using in vivo measurements was predicted with R2 > 0.73. Equations to predict chemical composition of the carcass from in vivo measurements showed R2 lower (R2 < 0.68) than observed for empty body, except for the water (R2 = 0.84). The independent variables SBW, uRF, and AG were sufficient to predict the fat, water, energy components of the empty body, whereas for estimation of protein content the uRF, HH, and SBW were satisfactory. For the calculation of the ash, the SBW variable in the equation was sufficient. Chemical compounds from components of the empty body of Nellore cattle can be calculated by the following equations: protein (kg) = 47.92 + 0.18 × SBW - 1.46 × uRF - 30.72 × HH (R² = 0.94, RMSPE = 1.79); fat (kg) = 11.33 + 0.16 × SBW + 2.09 × uRF - 0.06 × AG (R² = 0.74, RMSPE = 4.18); water (kg) = - 34.00 + 0.55 × SBW + 0.10 × AG - 2.34 × uRF (R² = 0.96, RMSPE = 5.47). In conclusion, the coefficients of determination (for determining the chemical composition of the empty body) of the equations derived from in vivo measures were higher than those of the equations obtained from rib section measurements taken postmortem, and better than coefficients of determination of the equations to predict the chemical composition of the carcass. [ABSTRACT FROM AUTHOR]

Effects of live yeast (Saccharomyces cerevisiae) in steam-flaked corn-based diets fed to natural-program beef cattle on growth performance, total tract apparent digestibility, carcass characteristics, and feeding behavior were evaluated in a randomized block design experiment. Steers (n = 144; 341 ± 7.03 kg) were blocked by initial BW and assigned randomly to 1 of the 3 treatments (n = 12 pens per treatment with 4 steers per pen). Treatments included the following: 1) control (CTL; no yeast); 2) low yeast (LY; 1.5 g/animal daily [3 × 1010 CFU]); and 3) high yeast (HY; 3.0 g/animal daily [6 × 1010 CFU]). Technologies such as implants, ionophores, and antibiotics were not used, and the steam-flaked corn-based finishing diets were fed to provide ad libitum access to feed. Yeast was included in a cottonseed meal- based premix as 1% of the dietary DM. Spot fecal samples (twice daily for 5 consecutive days) and diets were composited by pen and analyzed for acid insoluble ash to estimate apparent total tract digestibility of nutrients. Cattle were slaughtered on days 183 (4 blocks) and 204 (8 blocks). Dry matter intake (P ≥ 0.29), ADG (P ≥ 0.17), and G:F (P ≥ 0.33) did not differ among treatments. The percentage of Premium Choice (P < 0.01) carcasses increased linearly with increasing yeast inclusion in the diet. A quadratic response was observed for total tract apparent digestibility, in which steers fed LY had greater digestibility (P < 0.01) of DM by 5.4%, OM by 4.8%, NDF by 15.2%, ADF by 20.2%, CP by 6.2%, and ether extract (EE) by 2.5% compared with steers fed CTL. Feeding behavior was not affected (P = 0.28) by treatments. Live yeast improved digestibility of DM, OM, CP, EE, and fiber, without changing feeding behavior and growth performance of natural-program steers fed steam-flaked corn-based finishing diets. [ABSTRACT FROM AUTHOR]

A total of 360 pigs (DNA 200 × 400, initially 5.9 ± 0.1 kg) were used in a 42 d trial to determine the effect of high doses of a recently available phytase source (Natuphos E 5000 G, BASF Corporation, Florham Park, NJ) on nursery pig growth and bone ash. Pigs were randomly allotted to pens at weaning by BW and pens were allotted to one of eight corn-soybean meal-based dietary treatments in a randomized complete block design. There were five pigs per pen and nine pens per treatment. Diets were fed in three phases (d 0 to 7, 7 to 21, and 21 to 42) with formulated total calcium:phosphorus (Ca:P) of 1.07, 1.05, and 0.93, respectively. Treatments included a negative control (NC) with 0.40, 0.30, or 0.25% aP from monocalcium P for Phases 1, 2, and 3 respectively; and NC with either 500, 1,000, 2,000, 3,000, or 4,000 FTU/kg phytase. The last two treatments were a positive control (PC) with 0.55, 0.45, or 0.40% aP from monocalcium P for Phases 1, 2, and 3, respectively, or PC with 2,000 FTU/kg phytase. The NC diet with 500 FTU/kg and PC without added phytase were formulated to be equivalent in available Ca and P. On d 42, one pig per pen was euthanized and the right fibula was removed for bone ash analysis. From d 0 to 42, pigs fed increasing phytase in the NC tended to have increased (quadratic, P = 0.064) ADG and (linear, P = 0.082) ending BW and had improved (quadratic, P = 0.008) G:F. Adding 2,000 FTU/kg phytase to the PC did not influence ADG or ADFI, but tended to improve (P = 0.060) G:F compared with the PC. In addition, percentage bone ash increased as phytase increased in the NC (linear, P < 0.001) or when 2,000 FTU/kg was added to the PC diets (P < 0.001). Pigs fed the PC had increased (P = 0.007) ADFI and tended to have greater (P = 0.099) percentage bone ash than pigs fed NC+500 FTU/kg phytase, but the pigs fed NC+500 FTU/kg phytase had improved (P = 0.032) G:F compared to pigs fed the PC. In summary, increasing concentrations of dietary phytase in a P-deficient diet improved growth and bone ash measurements, and was optimized at 1,000 FTU/kg. There were varied improvements when 2,000 FTU/kg phytase was added in P adequate diets. [ABSTRACT FROM AUTHOR]

Data were collected from 1953 through 1980 from identical and fraternal twin beef and dairy females born in 1953, 1954, 1959, 1964, and 1969, from crossbred females born as singles in 1974, and their progeny. Numbers of dams that weaned at least one calf and were included in the first analysis were 37, 45, and 56 in the 1964, 1969, and 1974 data sets, respectively. Respective numbers of dams that weaned three calves and were included in a second analysis were 6, 8, 8, 22, 33, and 33 in the 1953, 1954, 1959, 1964, 1969, and 1974 experiments. Individual feed consumption was measured at 28-d intervals from the time females were placed on the experiment at 240 d of age until three calves were weaned or the dams had reached 5 yr of age. Residual feed intake (RFI) and residual BW gain (RG) of heifers that subsequently became dams were determined based on ADG and DMI from 240 d of age to first calving. Various measures of cow efficiency were calculated on either a life cycle or actual lifetime basis using ratios of progeny and dam weight outputs to progeny and dam feed inputs. The correlation between RFI and DMI was large and positive (r = 0.67; P < 0.0001), and RG was highly correlated with ADG (r = 0.75; P < 0.0001). Correlations of RFI with cow efficiency ratios that included harvest weight, carcass weight, or weight of trimmed wholesale cuts as measures of output ranged from -0.05 (P > 0.10) to -0.17 (P < 0.10), indicating that heifers with better (i.e., more negative) RFI values tended to become slightly more efficient cows. Correlations of RG with life cycle and actual lifetime cow efficiency ratios ranged from 0.08 (P > 0.10) to 0.23 (P < 0.05), demonstrating that heifers with better (i.e., more positive) values for RG were somewhat more efficient as cows. The correlations were stronger when cow salvage value was included in the measures of cow efficiency. Correlations of DMI and mid-test metabolic BW (MMW) with life cycle cow efficiency ratios that did not include cow salvage value as output ranged from -0.15 (P < 0.10) to -0.22 (P < 0.01). Correlations of DMI and MMW with actual lifetime cow efficiency ratios varied from -0.20 (P < 0.05) to -0.36 (P < 0.001). Therefore, smaller heifers that consumed less feed had superior cow efficiency ratios. Correlations of RFI with carcass grade, backfat thickness, marbling score, and kidney fat of progeny indicated that heifers with superior RFI would tend to produce leaner offspring. [ABSTRACT FROM AUTHOR]

Effects of a tannic acid blend (ByPro; Silvateam USA, Ontario, CA) added to steam-flaked corn-based fishing diets on beef cattle growth performance, carcass characteristics, nutrient digestibility, fecal N volatilization, and meat lipid oxidation were evaluated. Steers (n = 144; 349 ± 25 kg initial BW) were blocked by initial BW and assigned randomly to 1 of 3 treatments with 12 pens/treatment and 4 steers/pen and fed ad libitum. Treatments included a control (CON; no ByPro) and ByPro fed at 30 or 60 g DM/steer daily (30-ByPro and 60-ByPro, respectively). Pen fecal samples were collected 7 d after cattle were shipped to slaughter for estimation of N volatilization. Strip loins were aged for 21 d for evaluation of color and antioxidant activity. Intake quadratically increased (P = 0.05) from d 0 to 35, whereas linear trends were observed for increased DMI from d 0 to 105 and d 0 to slaughter (P = 0.07 and P = 0.06, respectively), resulting in a 3.7% greater overall DMI for 60-ByPro than for CON. No differences were detected for carcass-adjusted ADG (P = 0.65) or G:F (P = 0.17). Carcass characteristics including HCW (P = 0.52), fat thickness (P = 0.32), LM area (P = 0.57), quality grade (P = 0.44), yield grade (P = 0.29), and percentage of condemned livers (P = 0.13) were not affected by treatments. Apparent total tract digestibility of starch linearly decreased tendency (P = 0.03) with increasing ByPro dose, whereas tends for a linear decrease (P = 0.09) in CP and a quadratic increase (P = 0.09) in OM digestibility were observed. No effects of treatment (P = 0.39) were noted for fecal N volatilization. An increase (P < 0.01) in metmyoglobin in strip loin steaks was observed with ByPro inclusion. Oxymyoglobin decreased (P < 0.01) as display day progressed, except on d 5, at which time CON and 30-ByPro steaks had lower proportions than 60-ByPro steaks. Only subtle changes in discoloration ratio and deoxymyoglobin were observed, whereas no effects (P = 0.43) for pH or thiobarbituric acid reactive substances were noted. Feeding ByPro increased DMI during the first half of the feeding period without negatively affecting gain efficiency; however, fecal N retention was not altered by ByPro. ByPro did not negatively affect meat quality or carcass characteristics, and it did not seem to affect retail meat antioxidant activity. [ABSTRACT FROM AUTHOR]

Ionophores and antibiotics have been shown to decrease ruminal methanogenesis both in vitro and in vivo but have shown little evidence toward a sustainable means of mitigation. Feed additive rotation was proposed and investigated for methane, VFA, and microbial population response. In the present study, cannulated steers (n = 12) were fed a moderateforage basal diet in a Calan gate facility for 13 wk. In addition to the basal diet, steers were randomly assigned to 1 of 6 treatments: 1) control, no additive; 2) bambermycin, 20 mg bambermycin/d; 3) monensin, 200 mg monensin/d; 4) the basal diet + weekly rotation of bambermycin and monensin treatments (B7M); 5) the basal diet + rotation of bambermycin and monensin treatments every 14 d (B14M); and 6) the basal diet + rotation of bambermycin and monensin treatments every 21 d (B21M). Steers were blocked by weight in a randomized complete block design where the week was the repeated measure. Rumen fluid was collected weekly for analysis (n = 13), and results were normalized according to individual OM intake (OMI; kg/d). Potential activity of methane production was not significantly different among treatments (P > 0.05). However, treatment tended to affect the CH4-to-propionate ratio (P = 0.0565), which was highest in the control and lowest in the monensin, B21M, and B14M treatments (0.42 vs. 0.36, 0.36, and 0.33, respectively). The CH4:propionate ratio was lowest in wk 2 and 3 (P < 0.05) but the ratio in wk 4 to 12 was not different from the ratio in wk 0. Week also affected total VFA, with total VFA peaking at wk 3 and plummeting at wk 4 (4.02 vs. 2.86 mM/kg OMI; P < 0.05). A significant treatment × week interaction was observed for the acetate-to-propionate (A:P) ratio, where bambermycin- and rotationally fed steers did not have a reduced A:P ratio compared with monensin-fed steers throughout the feeding period (P < 0.0001). Microbial analysis revealed significant shifts, but several predominant classes showed adaptation between 4 and 6 wk after additive initiation. There was no significant evidence to suggest that rotations of monensin and bambermycin provided additional benefits to steers consuming a moderate-forage diet at the microbial/animal and environmental level versus those continuously fed. [ABSTRACT FROM AUTHOR]

Modern sows have low feed intake (FI) during lactation. The main aim of this study was to understand interactions between and separate effects of FI and nutrient density on litter weaning weight (WW). Key drivers of colostrum intake (CIn), piglet survival, WW, and colostrum yield (CY) were also investigated. Sows (n = 82) were offered a High (15.8 MJ/kg DE; 1.3% total lysine) or Normal (15.2 MJ/kg DE; 1.28% total lysine) specification lactation diet at either a High (feed allowance increased by 0.5 kg/d after farrowing until intake reached 10 kg/d) or Low (feed allowance was increased by 0.3 kg/d after farrowing until intake reached 7.5 kg/d) feeding level (2 × 2 factorial design). A subset of sows (n = 18) were observed during farrowing to collect data on factors affecting CIn. No interactions were found between diet specification and feeding level. Sows on the Low feeding level lost 10.6 kg more BW during lactation than those on the High feeding level (P < 0.001). Sows offered the High specification diet lost 6.4 kg more BW than those on the Normal specification diet (P = 0.018). Diet specification had no effect on ADFI. Between birth and weaning, litters of sows offered the High feeding level grew 326 g/d faster (P <0.001) and were heavier at 28 d (114 kg; P < 0.001) compared with those of sows offered the Low feeding level (104 kg). Although litters from sows offered the High specification diet had WW similar to that of litters from sows offered the Normal specification diets, their ADG was 190 g/d greater (P = 0.018) between birth and weaning. A regression analysis was completed using data from 192 sows and indicated that FI and lysine intake throughout lactation and DE and lysine intake from 14 to 28 d of lactation were the main drivers of litter WW. Lactation efficiency was 0.65 from 0 to 7 d and decreased to 0.42 from 21 to 28 d. Variation in CIn was mainly explained by 24-h weight, birth weight, and the duration of farrowing. Colostrum yield was significantly correlated (P = 0.004; pseudo R2 = 54.5%) with litter birth weight. Piglet WW was positively correlated with 3-wk weight (P < 0.001) but negatively correlated with sow parity (P = 0.035), number born alive (P = 0.045), and being female (P < 0001). Out of 45 variables, preweaning piglet survival was positively correlated (P = 0.008) with only 24- to 48-h weight gain. In conclusion, lactation FI and DE and lysine intake in the second half of lactation were the main drivers of litter WW. [ABSTRACT FROM AUTHOR]

This study evaluated effects of ground redberry juniper (Juniperus pinchotii) and urea in dried distillers grains with solubles-based supplements fed to Rambouillet ewe lambs (n = 48) on rumen physiological parameters and bacterial diversity. In a randomized study (40 d), individually-penned lambs were fed ad libitum ground sorghum-sudangrass hay and of 1 of 8 supplements (6 lambs/treatment; 533 g/d; as-fed basis) in a 4 × 2 factorial design with 4 concentrations of ground juniper (15%, 30%, 45%, or 60% of DM) and 2 levels of urea (1% or 3% of DM). Increasing juniper resulted in minor changes in microbial β-diversity (PERMANOVA, pseudo F = 1.33, P = 0.04); however, concentrations of urea did not show detectable broad-scale differences at phylum, family, or genus levels according to ANOSIM (P > 0.05), AMOVA (P > 0.10), and PERMANOVA (P > 0.05). Linear discriminant analysis indicated some genera were specific to certain dietary treatments (P < 0.05), though none of these genera were present in high abundance; high concentrations of juniper were associated with Moraxella and Streptococcus, low concentrations of urea were associated with Fretibacterium, and high concentrations of urea were associated with Oribacterium and Pyramidobacter. Prevotella were decreased by juniper and urea. Ruminococcus, Butyrivibrio, and Succiniclasticum increased with juniper and were positively correlated (Spearman's, P < 0.05) with each other but not to rumen factors, suggesting a symbiotic interaction. Overall, there was not a juniper × urea interaction for total VFA, VFA by concentration or percent total, pH, or ammonia (P > 0.29). When considering only percent inclusion of juniper, ruminal pH and proportion of acetic acid linearly increased (P < 0.001) and percentage of butyric acid linearly decreased (P = 0.009). Lamb ADG and G:F were positively correlated with Prevotella (Spearman's, P < 0.05) and negatively correlated with Synergistaceae, the BS5 group, and Lentisphaerae. Firmicutes were negatively correlated with serum urea nitrogen, ammonia, total VFA, total acetate, and total propionate. Overall, modest differences in bacterial diversity among treatments occurred in the abundance or evenness of several OTUs, but there was not a significant difference in OTU richness. As diversity was largely unchanged, the reduction in ADG and lowerend BW was likely due to reduced DMI rather than a reduction in microbial fermentative ability. [ABSTRACT FROM AUTHOR]

Apprehension among consumers is mounting on the efficiency by which cattle convert feedstuffs into human edible protein and energy as well as the consequential effects on the environment. Most (genetic) studies that attempt to address these issues have generally focused on efficiency metrics defined over a certain time period of an animal's life cycle, predominantly the period representing the linear phase of growth. The age at which an animal reaches the carcass specifications for slaughter, however, is also known to vary between breeds; less is known on the extent of the within-breed variability in age at slaughter. Therefore, the objective of the present study was to quantify the phenotypic and genetic variability in the age at which cattle reach a predefined carcass weight and subcutaneous fat cover. A novel trait, labeled here as the deviation in age at slaughter (DAGE), was represented by the unexplained variability from a statistical model, with age at slaughter as the dependent variable and with the fixed effects, among others, of carcass weight and fat score (scale 1 to 15 scored by video image analysis of the carcass at slaughter). Variance components for DAGE were estimated using either a 2-step approach (i.e., the DAGE phenotype derived first and then variance components estimated) or a 1-step approach (i.e., variance components for age at slaughter estimated directly in a mixed model that included the fixed effects of, among others, carcass weight and carcass fat score as well as a random direct additive genetic effect). The raw phenotypic SD in DAGE was 44.2 d. The genetic SD and heritability for DAGE estimated using the 1-step or 2-step models varied from 14.2 to 15.1 d and from 0.23 to 0.26 (SE 0.02), respectively. Assuming the (genetic) variability in the number of days from birth to reaching a desired carcass specifications can be exploited without any associated unfavorable repercussions, considerable potential exists to improve not only the (feed) efficiency of the animal and farm system but also the environmental footprint of the system. The beauty of the approach proposed, relative to strategies that select directly for the feed intake complex and enteric methane emissions, is that data on age at slaughter are generally readily available. Of course, faster gains may potentially be achieved if a dual objective of improving animal efficiency per day coupled with reduced days to slaughter was embarked on. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of dietary chromium, CLA, and ractopamine on performance, carcass traits, and pork quality of finishing pigs slaughtered at 115 kg BW. Ninety-six crossbred barrows (initial BW = 70.21 ± 1.98 kg) were randomly assigned to 1 of 6 dietary treatments. There were 8 replicates per treatment (48 pens; 2 pigs/pen). A diet formulated according to the nutritional requirements was used as the control (CON). The other 5 diets were based on the CON and supplemented as follows: 0.4 mg/kg Cr yeast (CrY); 0.5% CLA; 0.4 mg/kg CrY and 0.5% CLA (CrY + CLA); 20 mg/kg ractopamine (RAC); 0.4 mg/ kg CrY and 20 mg/kg RAC (CrY + RAC). Lysine levels on diets containing ractopamine were raised by 20% compared to CON to meet the greater requirements of pigs fed ractopamine. Pigs fed RAC and CrY + RAC were fed CON for the first 17 d, and then the respective diets for the last 28 d on trial. Data were analyzed in a model including the fixed effect of treatment (6 levels) and initial BW as a covariate for all characteristics, with the exception of carcass traits, in which final BW was used as a covariate. Least-squares means were separated using Tukey-Kramer's method. Differences were considered when probability values were lower than 0.05. Pigs fed RAC and CrY + RAC had the greatest (P < 0.001) final BW and ADG. Pigs fed CrY + RAC had greater (P < 0.001) G:F than pigs within the other groups, except for those fed RAC. Pigs fed CrY + RAC and RAC had similar G:F, both greater (P < 0.001) than pigs fed CON. Average daily feed intake was similar (P = 0.83) for all diets. Pigs fed CrY + RAC had greater LM area (P = 0.01) and carcass yield (P < 0.02) than pigs fed CON, CrY, CLA, and CrY + CLA. Loin muscle area and carcass yield of pigs fed RAC were not different from pigs fed the others diets. Pigs fed CON diets had greater BF (P = 0.02) than pigs fed CLA diet. Additives did not affect (P > 0.05) pork quality, except for color. No differences (P > 0.05) were observed for carcasses pH and temperature. The L* values for pigs fed RAC were greater (P = 0.01) than pigs fed other diets. Pigs fed RAC had lower (P < 0.01) a* values compared to pigs fed other experimental diets. Serum urea nitrogen concentration (SUN) was lower (P = 0.02) in pigs fed CrY + RAC than in pigs fed CON and RAC and similar to pigs fed the other feeding additives. In summary, it was demonstrated that, when combined, CrY and RAC increase LM area and carcass yield, and reduce SUN, suggesting that chromium could improve nutrient utilization by muscle cells in RAC-fed pigs. Additionally, the additives have no major effects on pork quality. [ABSTRACT FROM AUTHOR]

Angus cattle from 2 beef cattle projects in which daily methane production (MPR) was measured were used in this study to examine the nature of the relationships among BW, DMI, and methane traits of beef cattle fed ad libitum on a roughage diet or a grain-based feedlot diet. In both projects methane was measured using the GreenFeed Emission Monitoring system, which provides multiple short-term breath measures of methane production. The data used for this study were from 119 Angus heifers over 15 d on a roughage diet and 326 Angus steers over 70 d on a feedlot diet. Mean (±SD) age, BW, and DMI were 372 ± 28 d, 355 ± 37 kg, and 8.1 ± 1.3 kg/d for the heifers and 554 ± 86 d, 577 ± 69 kg, and 13.3 ± 2.0 kg/d for the steers, respectively. The corresponding mean MPR was 212 g/d for heifers and 203 g/d for steers. Additional traits studied included methane yield (MY; MPR/DMI), methane intensity (MPR/ BW), and 3 forms of residual methane production (RMP), which is a measure of actual minus predicted MPR. For RMPB, RMPD, and RMPDB predicted MPR were obtained by regression of MPR on BW, on DMI, and on both DMI and BW, respectively. The 2 data sets were analyzed separately using the same statistical procedures. For both feed types the relationships between MPR and DMI and between MPR and BW were both positive and linear. The correlation between MPR and DMI was similar to that between MPR and BW, although the correlations were stronger for the roughage diet (r = 0.75 for MPR vs. DMI; r = 0.74 for MPR vs. BW) than the grain-based diet (r = 0.62 for MPR vs. DMI; r = 0.66 for MPR vs. BW). The correlation between MY and DMI was negative and moderate for the roughage (r = -0.68) and grain-based (r = -0.59) diets, a finding that is different from the nonsignificant correlations reported in studies of cattle on a restricted roughage diet. The 3 RMP traits were strongly correlated (r values from 0.76 to 0.99) with each other for both the roughage and the grain-based diets, which indicates that using RMPB to lower MPR could provide a result similar to using RMPD in cattle. As feed intake (DMI) is more difficult to measure than BW, this result implies that under ad libitum feeding situations in which DMI cannot be measured, RMPB can be used to identify higher- or lower-RMP animals with similar levels of effectiveness as RMPD. [ABSTRACT FROM AUTHOR]

Pigs housed in groups are remixed with unfamiliar individuals, which can trigger aggressive interactions, potentially compromising animal welfare. Skin lesions are a reliable indicator trait of aggression and are moderately heritable, suggesting that aggression may be reduced through selection. This study estimated genetic parameters of skin lesions of pigs at multiple life stages, explored genetic correlations of skin lesions between age groups and body location, and studied the relationship between skin lesions and production traits of commercial importance. A population of 1,079 Yorkshire pigs was strategically remixed into new groups of familiar and unfamiliar animals at 3 life stages (weaning, grow-finish, and mature gilts). Skin lesions (fresh, bright red cuts) were counted immediately prior to mixing and 24 h and 3 wk after mixing across 3 body regions: anterior, central, and caudal. Weights were recorded prior to each mixing event. Prior to slaughter, backfat thickness and loin muscle area were determined using ultrasound. Univariate analyses were performed to obtain heritability estimates of lesion scores. Bivariate analyses were performed with response variables being skin lesions, weight gain per life stage, backfat thickness, or loin muscle area, depending on the relationship of interest, to obtain correlations. Lesion score heritabilities ranged from 0.10 to 0.40 and were significant (P < 0.05). Heritability was highest for lesions on the anterior region of the body for 24 h and 3 wk after mixing. Lesions to the central and caudal areas showed the highest genetic correlation at each stage of production, whereas those to the anterior and caudal regions had the lowest correlation. The highest genetic correlation was found between the mature gilt and grow-finish stages, whereas the weaning and mature gilt stages had the lowest correlations. Genetic correlations between lesions and production traits were not significantly different from 0 for weight gain and backfat thickness, but loin muscle area was negatively correlated with lesions (P = 1.17 × 10-4, P = 2.30 × 10-5, and P = 6.08 × 10-4 for anterior, central, and caudal lesions, respectively). These results are promising for the industry because they suggest that pigs selected for reduced lesions will show increased loin muscle area without negative effects on growth. Alternatively, selection for these production traits would not increase lesions. [ABSTRACT FROM AUTHOR]

Coproduct feeding value may be improved by enzyme and microbial inoculant treatment in liquid diets. Three experiments were conducted to assess growth performance in newly weaned 20-d-old pigs fed corn- and soybean meal-based diets with untreated, steeped, or partially fermented distillers dried grains with solubles (DDGS) from day of weaning. In Exp. 1, conventionally dry fed diets with untreated DDGS (DDGS) or without DDGS (Control) were fed. In Exp. 2, liquid diets (25% DM [75% moisture]) were fed with enzymes (β-glucanase and xylanase at 67.2 and 51.4 U/g DDGS, respectively) added to dry DDGS at the time of liquid feeding (UNSTP) or steeped with DDGS and added to liquid feed from d 5 to 12 of each batch prior to liquid feeding (STP). In Exp. 1 and 2 DDGS inclusion levels were 7.5% in phase 1 (d 0 to 7) and 25% in phase 2 (d 7 to 21) and phase 3 (d 21 to 35). In Exp. 3 liquid diets were fed with the Exp. 2 enzymes and silage inoculant (360,000 combined cfu Pediococcus pentosaceus and Propionibacterium jensenii/g DDGS) added to dry DDGS at the time of liquid feeding (UNFER) or fermented with DDGS and added to liquid feed from d 1 to 7 of each batch before liquid feeding (FER). The inclusion levels of DDGS were 7.5% in phase 1 (d 0 to 7), 16.25% in phase 2 (d 7 to 21), and 25% in phase 3 (d 21 to 42 or 48). Experiment 3 diets were fed to light (LBWi; 5.8 ± 0.6 kg) or heavy (HBWi; 7.6 ± 0.8 kg) BW pigs at weaning, and results were analyzed separately. Pig BW and ADFI were measured weekly in each experiment. In Exp. 1, feeding diets with DDGS depressed (P < 0.05) ADFI on d 7 to 21 (491 vs. 375 ± 21 g DM/pig) and d 0 to 35 (456 vs. 405 ± 13 g DM/pig). In Exp. 2 growth performance was not affected. In Exp. 3 ADFI of HBWi pigs was not affected. The HBWi pigs fed FER had lower (P < 0.05) ADG and G:F on d 7 to 21 (323 vs. 264 ± 15 g/pig and 0.86 vs. 0.72 ± 0.02 g:g, respectively) and lower (P < 0.05) BW on d 21 (12.4 vs. 11.6 ± 0.2 kg) compared with HBWi pigs fed UNFER. The LBWi pigs fed FER had lower (P < 0.05) ADFI on d 0 to 7 and 7 to 21 (190 vs. 168 ± 3 and 318 vs. 273 ± 13 g DM/pig, respectively) and had greater (P < 0.05) ADG on d 42 to 48 (773 vs. 941 ± 60 g/pig) and BW on d 48 (24.5 vs. 25.8 ± 0.5 kg) compared with LBWi pigs fed UNFER. Results show that up to 25% DDGS inclusion in weaning pig diets did not affect overall growth performance. Liquidfed partially fermented DDGS had an influence on the growth performance of weanling pigs, particularly during the extended nursery period of pigs of light weaning weight in this study. [ABSTRACT FROM AUTHOR]

Utilization of feed in livestock species consists of a wide range of biological processes, and therefore, its efficiency can be expressed in various ways, including direct measurement, such as daily feed intake, as well as indicator measures, such as feeding behavior. Measuring feed efficiency is important to the swine industry, and its accuracy can be enhanced by using automated feeding systems, which record feed intake and associated feeding behavior of individual animals. Each automated feeder space is often shared among several pigs and therefore raises concerns about social interactions among pen mates with regard to feeding behavior. The study herein used a data set of 14,901 Duroc boars with individual records on feed intake, feeding behavior, and other off-test traits. These traits were modeled with and without the random spatial effect of Pen_Room, a concatenation of room and pen, or random social interaction among pen mates. The nonheritable spatial effect of common Pen-Room was observed for traits directly measuring feed intake and accounted for up to 13% of the total phenotypic variance in the average daily feeding rate. The social interaction effect explained larger proportions of phenotypic variation in all the traits studied, with the highest being 59% for ADFI in the group of feeding behaviors, 73% for residual feed intake (RFI; RFI4 and RFI6) in the feed efficiency traits, and 69% for intramuscular fat percentage in the off-test traits. After accounting for the social interaction effect, residual BW gain and RFI and BW gain (RIG) were found to have the heritability of 0.38 and 0.18, respectively, and had strong genetic correlations with growth and off-test traits. Feeding behavior traits were found to be moderately heritable, ranging from 0.14 (ADFI) to 0.52 (average daily occupation time), and some of them were strongly correlated with feed efficiency measures; for example, there was a genetic correlation of 0.88 between ADFI and RFI6. Our work suggested that accounting for the social common pen effect was important for estimating genetic parameters of traits recorded by the automated feeding system. Residual BW gain and RIG appeared to be two robust measures of feed efficiency. Feeding behavior measures are worth further investigation as indicators of feed efficiency. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to compare the effects of using 2 different forage sources on intake and sorting and feeding behavior in growing heifers fed a high-concentrate diet offered as a total mixed ration (TMR). Eight Simmental heifers (initial BW of 148.1 ± 4.83 kg) were used in a crossover design experiment. Treatment diets were a TMR with either barley straw (BS) or alfalfa hay (AH) as forage source. Diets were offered on an ad libitum basis, with a forage to concentrate ratio of 8 to 92. The experiment was performed in two 28-d periods, with 3 wk of diet adaptation and 1 wk of sampling in each period. Heifers were weighed before feeding on 2 consecutive days at the beginning and the end of the experiment, and in the sampling week. Feed and refusal samples were collected daily in the sampling week for DM determination and chemical analysis. Particle size separation was performed using the 3-screen Penn State Particle Separator. Dry matter digestibility was estimated using acid-insoluble ash as internal marker. Feeding behavior was recorded using an automated feeding system. Sorting behavior was measured with the intake of different particle size. Dry matter intake was greater (P < 0.05) in heifers fed BS (6.7 kg/d) than AH (5.8 kg/d) when these animals faced TMR for first time in period 1, but DMI did not differ between diets in period 2 when they were accustomed to the method of feeding. Apparent DM digestibility did not differ between diets (62.7 and 64.3% for BS and AH, respectively). Heifers fed BS sorted in both periods against long particle size (P < 0.01) and against medium particle size in period 2 (P < 0.01), a behavior that did not appear in heifers fed AH. Heifers sorted for short particle size in both diets in period 1, this behavior being maintained in period 2 for heifers fed BS, while it disappeared in heifers fed AH. This sorting behavior preferentially shown in heifers fed BS resulted in a tendency (P = 0.06) for greater length of each meal and a longer feeding time (P = 0.02). In conclusion, at 8% of incorporation, forage source affected intake in only 1 of the 2 experimental periods. Heifers fed BS showed a sorting behavior with preferential consumption for concentrate in the TMR, feeding time being greater in BS than in AH. In contrast, heifers fed AH sorted for short particle size when faced for the first time with a new method of feeding, this sorting behavior disappearing once heifers had got familiar with it. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the impact of cattle finishing diet and muscle type on meat quality. Consumer sensory response, proximate composition, Warner-Bratzler shear force (WBSF), fatty acid composition, and volatile compounds were assessed from the gluteus medius (GM) and triceps brachii (TB) muscles of cattle (n = 6 per diet) which were grain-finished (USUGrain) on conventional feedlot or 2 forage diets, a perennial legume, birdsfoot trefoil-finished (USUBFT; Lotus corniculatus), and grass-finished (USUGrass; Bromus riparius). Diet had an interacting effect with muscle for all sensory attributes (P = 0.002), except aroma and flavor (P ≥ 0.078). In forage-finished beef, tenderness, fattiness, overall liking, and WBSF tenderness of GM was greater (P < 0.05) than TB, whereas for USUGrain, the tenderness, fattiness, overall liking, and WBSF tenderness of both muscles were similar (P > 0.05) but the juiciness of TB was more liked than USUGrain GM (P < 0.05). The juiciness of foragefinished beef did not differ (P > 0.05) between GM and TB. Lower (P < 0.05) intramuscular fat (IMF) percent was determined for USUGrass beef in comparison with USUGrain beef. The IMF percent of USUBFT beef was similar (P > 0.05) to both USUGrass and USUGrain beef. However, IMF percent was not impacted by muscle type (P = 0.092). The ratio of n-6:n-3 fatty acids was affected by muscle dependent on diet (P = 0.016). The ratio of n-6:n-3 fatty acids was affected by the interaction of muscle × diet (P = 0.016). Between forage diets (USUGrass and USUBFT), n-6:n-3 ratios were similar (P > 0.05) between GM and TB, whereas within USUGrain, the GM was greater (P < 0.05) than the TB. Cumulative MUFA was greater (P < 0.05) in USUGrain compared with both USUGrass and USUBFT, which were similar (P > 0.05). Strecker aldehydes, ketones, pyrazines, and methional were affected (P ≤ 0.036) by muscle and found to have a greater concentration in GM compared with TB. Overall, consumers determined that USUGrain GM and TB had similar (P > 0.05) quality ratings. However, within forage-finished beef, the GM was perceived more frequently (P < 0.05) to be of premium quality and the forage-finished TB was more frequently (P < 0.05) rated as having unsatisfactory quality. These findings were in agreement with ratings of tenderness and overall liking. Therefore, in the context of our consumer group grilled GM and TB steaks, grain-finished beef provided more uniform quality and eating experience compared with forage-finished beef. [ABSTRACT FROM AUTHOR]

Research was conducted to determine the effect of feeding de-oiled wet distillers grains plus solubles (WDGS) on beef fatty acid profile, retail shelf life and development of oxidation products during retail display (RD). A total of 336 crossbred yearling steers (initial BW = 351.08 ± 19.05 kg) were fed 1 of 7 dietary treatments: an all corn control (1:1 blend of dry rolled and high moisture corn), 35%, 50%, or 65% inclusion of WDGS, either full-fat or de-oiled. Within each treatment 15 Choice carcasses were randomly selected (n = 105), strip loins were obtained, aged 7 and 21 d, and representative steaks from each strip loin were placed in RD conditions for 7 d. Fatty acid profiles were determined (mg/100 g tissue basis) and differences (P ≤ 0.05) were found in the C16:1, C18:1T, C18:2 and total polyunsaturated fatty acids (PUFA) among dietary treatments. Palmitoleic acid (C16:1) was predominant (P < 0.0001) in the corn control group, intermediate in the 35% de-oiled WDGS group, but no differences (P > 0.05) were observed between all other diets. Elaidic acid (C18:1T) was greater (P = 0.01) in the 65% full-fat WDGS group, least for the corn control group, and intermediate for all other diets. Linoleic acid (C18:2) was greater (P = 0.0001) in all 3 full-fat WDGS groups and 65% deoiled WDGS group (290.98 mg/100 g, on average), intermediate in the 50% and 35% de-oiled WDGS groups (231.08 and 227.16 mg/100 g, respectively) and least for the corn control group (177.70 mg/100 g). The PUFA content was greater (P < 0.01) in all 3 full-fat WDGS groups and 65% de-oiled WDGS group (337.13 mg/100 g, on average), intermediate in the 50% and 35% de-oiled WGDS groups (274.77 and 273.84 mg/100 g, respectively) and least for the corn control group (223.98 mg/100 g). Dietary treatment did not alter discoloration (P = 0.30) or lipid oxidation (P = 0.36). Shear force decreased with age and RD (P < 0.0001) but dietary treatment had no effect on shear force (P = 0.93). In general, feeding 35% and 50% deoiled WDGS had intermediate PUFA content relative to a corn control or full-fat WDGS diet. Feeding deoiled WDGS did not seem to increase beef shelf life and does not negatively alter beef quality parameters in relation to full-fat WDGS. [ABSTRACT FROM AUTHOR]

Livestock managers dealing with inter and intra-annual forage quality dynamics use a variety of adaptive systems to cope. In higher rainfall areas, managers may have the ability to manipulate forage quantity and quality through for age management tactics such as grazing management, fertilization and use of seeded forages. In more semiarid and arid areas, forage dynamics are more heavily controlled by climatic factors. In these regions, adaption of animal management systems, such as by adjusting the match-up between seasonal nutrient demand and supply through manipulation of the animals’ physiological state, or through the use of mobility, may be more appropriate. Understanding factors affecting forage dynamics and how managers develop systems to adjust is important to helping these managers to deal with future changes in climate and land use. This review describes livestock system adaptations used to deal with high and variable inter- and intra-annual forage dynamics primarily found in arid and semiarid production zones. [ABSTRACT FROM AUTHOR]

One hundred ninety-two pigs were blocked by age and stratified by initial BW (25.7 ± 2.3 kg) into pens (2 barrows and 2 gilts/pen), and within blocks, pens were assigned randomly to 1 of 4 treatments in a 2 x 2 factorial arrangement, with main effects of diet form (meal vs. pelleted) and distillers dried grains with solubles (DDGS) inclusion (0% vs. 30%). Pigs were slaughtered after a 91-d feeding trial, and carcasses were fabricated after a 24-h chilling period. Belly dimensions and flop distance were measured, and an adipose tissue sample from each belly was collected for fatty acid analysis. Bacon was manufactured at a commercial processing facility before being returned to the University of Illinois Meat Science Laboratory for further evaluation. Although bellies from pigs fed pelleted diets were 5.3% heavier (P < 0.01) than bellies from meal-fed pigs, belly weight as a percentage of chilled side weight (P = 0.55) and fresh belly dimensions (P ≥ 0.11) were not affected by diet form. Slab bacon weight and cooked yield were greater (P ≤ 0.01) for bellies from pellet-fed than meal-fed pigs. Despite pellet-fed pigs having a 3.1-unit greater iodine value (IV) than meal-fed pigs, there was no effect (P ≥ 0.16) of diet form on commercial bacon slicing yields. Bacon slabs from pellet-fed pigs produced more (P < 0.01) total bacon slices, but 3.1% fewer (P < 0.01) slices per kilogram than slabs from meal fed pigs. Inclusion of 30% DDGS reduced belly thickness (P < 0.001), flop distance (P < 0.001), and initial belly weight (P = 0.04) by 0.32 cm, 4.97 cm, and 2.85, respectively, and increased (P < 0.001) belly fat IV by 7.1 units compared with bellies from pigs fed 0% DDGS. Feeding 0% DDGS produced more (P < 0.01) total bacon slices than feeding 30% DDGS. Distillers dried grains with solubles inclusion had no effect on slice yields (P ≥ 0.14) or slices per kilogram (P = 0.08). Overall, bellies from pellet-fed pigs were heavier and had greater IV but did not differ in commercial slicing yields from meal-fed pigs. Feeding pigs 30% DDGS produced thinner, softer bellies with greater IV, but slicing yields were not different from bellies of pigs fed 0% DDGS. Thus, swine producers can feed pelleted diets, without or with 30% DDGS, without negatively affecting commercial bacon slicing yield. [ABSTRACT FROM AUTHOR]

Three experiments were conducted to evaluate the feeding of dried distillers' grains with solubles (DDGS) in sow lactation diets. In Exp. 1, 168 multiparous sows (PIC, Camborough 22) were fed a 10% DDGS diet throughout gestation. Sows were randomly allotted to 1 of 4 corn-soybean meal lactation diets formulated to contain different levels of DDGS (0, 10, 20, and 30%, respectively). All diets were formulated to be isocaloric (3.46 Mcal ME/kg) and all other nutrients exceeded NRC (1998) nutrient recommendations. Sow ADFI was not different (P > 0.10) as DDGS level increased. Increasing DDGS resulted in a linear (P < 0.03) increase in sow weight gain (7.5, 11.3, 20.3, and 17.2 kg, respectively) and a reduction in wean-to-first-service interval (7.1, 5.2, 5.0, and 4.9 d, respectively). Increasing DDGS did not affect subsequent total born per litter (13.7, 12.8, 13.3, and 12.3, respectively; P > 0.10). In Exp. 2 and 3, lactation diets consisted of corn and 20, 30, 40, or 50% DDGS. Diets were formulated at 3.25 Mcal ME/kg, 1.05% standardized ileal digestible lysine, and all other nutrients to exceed NRC (1998) nutrient recommendations. In both experiments, sows (PIC, Camborough) were fed 40% DDGS in gestation and allocated to a randomized complete block based on the parity of the sow at the time of entry into the farrowing house. In Exp. 2, 256 gilts and multiparous sows were fed the randomly assigned diets. As DDGS inclusion increased, sow feed intake (6.2, 6.2, 6.0, and 5.9 kg/d, respectively) and sow weight gain (10.5, 10.3, 8.2, and 6.2 kg, respectively) tended to linearly decrease (P < 0.06). Sow wean to estrus differed between 20 and 30% DDGS inclusion (4.9 vs. 6.9 d; P < 0.01). Litter gain was not different (2.55, 2.53, 2.51, and 2.59 kg/d, respectively; P > 0.10) as DDGS inclusion increased. In Exp. 3, 98 multiparous sows were randomly allotted to 1 of the 4 experimental diets during the summer months. Sow feed intake, sow weight gain, and litter gain were not different (P > 0.10) between treatments. The data suggest that feeding high levels of DDGS of 40 to 50% may reduce sow feed intake and litter performance. These results demonstrate that feeding up to 30% DDGS in lactation diets can be done without adversely influencing sow or litter performance. [ABSTRACT FROM AUTHOR]

To investigate the effects of feed condition and breed on the level of DNA methylation for the uncoupling protein 3 (UCP3) gene, which is an important candidate gene for regulating intramuscular fat (IMF) content in chicken breast muscle, breast muscle of Daninghe (DNH) and Qingjiaoma (QJM) chickens under scatter-feed and captivity-feed conditions was analyzed. Using RNA sequencing, 47 and 113 candidate genes were determined to be related to feed conditions and breed, respectively, and 7 differentially expressed genes were confirmed by real-time quantitative PCR, including UCP3. The mRNA levels of UCP3 were significantly different between the 2 feed conditions. The DNA region from bp +1700 to +2459 of the UCP3 gene was studied using the bisulfite sequencing method and contained 46 methylation sites and 3 CpG islands. The results showed that the methylation level of this UCP3 region was lower in DNH chickens (0.77% to 0.88%, P = 0.012) and QJM chickens (0.88% to 0.91%, P = 0.20) under scatter-feed conditions than under captivity-feed conditions. The mean methylation level of UCP3 in DNH chickens was lower than that in QJM chickens under scatter-feed conditions (DNH to QJM, 0.77% to 0.88%, P = 0.007), which suggests that breed affects the mean methylation level of UCP3 under scatter-feed conditions. In summary, our findings suggest that feed condition and breed affect the methylation of UCP3 in chicken breast muscle. [ABSTRACT FROM AUTHOR]

The objectives of this experiment were to determine growth performance, visceral mass differences, carcass characteristics, fresh meat quality, and carcass cutability of growing-finishing pigs fed diets containing high-protein canola meal (CM-HP) or conventional canola meal (CM-CV). Seven dietary treatments were fed to investigate effects of increasing inclusion rates of CM-HP or CM-CV in a corn-soybean meal diet containing no canola meal (control). Inclusion rates were 33, 66, or 100% replacement of soybean meal with either CM-HP or CM-CV. Pigs (140 barrows and 140 gilts; 2 barrows and 2 gilts per pen) were fed experimental diets in 3 phases with each phase lasting 35, 28, and 28 d, respectively. Within each phase, diets were formulated to be similar in concentrations of standardized ileal digestible indispensable AA and in standardized total tract digestible P, but NE concentrations were not equalized among diets. At the conclusion of the experiment, 1 pig per pen was harvested. Over the 91-d growing-finishing period, no effects of CM-HP on ADG, ADFI, or G:F were observed, but final BW tended (P = 0.06) to be reduced as increasing levels of CM-HP were included in the diets. There was a linear increase (P < 0.05) in ADFI and a linear reduction (P < 0.05) in G:F as CM-CV inclusion level increased. Pigs fed CM-CV also had greater (P < 0.05) ADG and ADFI than pigs fed diets containing CM-HP. There was a linear increase (P < 0.01) in liver weights, as a percentage of live weight, as CM-CV inclusion increased, but that was not the case if CM-HP was included in the diets. There was a linear increase (P < 0.05) in kidney weights, as a percentage of live weight, as CM-HP or CM-CV inclusion increased. There were no differences among treatments for ending live weight, HCW, carcass yield, loin eye area, 10th rib backfat thickness, or estimated carcass lean. Shear force, cook loss, LM moisture, LM extractible lipid, and drip loss were also not different among treatment groups. There were no differences among treatments for any subjective LM quality evaluations (color, marbling, firmness). Pigs fed CM-HP had increased (P < 0.05) boneless lean cutting yields and boneless carcass cutting yields compared with pigs fed CM-CV. In conclusion, CM-HP and CM-CV may fully replace soybean meal as protein supplements in growing- finishing pig diets without substantially impairing pig performance or carcass quality. [ABSTRACT FROM AUTHOR]

The DE values of corn grain for pigs will differ among corn sources. More accurate prediction of DE may improve diet formulation and reduce diet cost. Corn grain sources (n = 83) were assayed with growing swine (20 kg) in DE experiments with total collection of feces, with 3-wk-old broiler chick in nitrogen-corrected apparent ME (AMEN) trials and with cecectomized adult roosters in nitrogen-corrected true ME (TMEN) studies. Additional AMEN data for the corn grain source set was generated based on an existing near-infrared transmittance prediction model (nearinfrared transmittance-predicted AMEN [NIT-AMEN ]). Corn source nutrient composition was determined by wet chemistry methods. These data were then used to 1) test the accuracy of predicting swine DE of individual corn sources based on available literature equations and nutrient composition and 2) develop models for predicting DE of sources from nutrient composition and the cross-species information gathered above (AMEN, NIT-AMEN , and TMEN ). The overall measured DE, AMEN , NIT-AMEN , and TMEN values were 4,105 ± 11, 4,006 ± 10, 4,004 ± 10, and 4,086 ± 12 kcal/kg DM, respectively. Prediction models were developed using 80% of the corn grain sources; the remaining 20% was reserved for validation of the developed prediction equation. Literature equations based on nutrient composition proved imprecise for predicting corn DE; the root mean square error of prediction ranged from 105 to 331 kcal/kg, an equivalent of 2.6 to 8.8% error. Yet among the corn composition traits, 4-variable models developed in the current study provided adequate prediction of DE (model R2 ranging from 0.76 to 0.79 and root mean square error [RMSE] of 50 kcal/kg). When prediction equations were tested using the validation set, these models had a 1 to 1.2% error of prediction. Simple linear equations from AMEN, NIT-AMEN , or TMEN provided an accurate prediction of DE for individual sources (R2 ranged from 0.65 to 0.73 and RMSE ranged from 50 to 61 kcal/kg). Percentage error of prediction based on the validation data set was greater (1.4%) for the TMEN model than for the NIT-AMEN or AMEN models (1 and 1.2%, respectively), indicating that swine DE values could be accurately predicted by using AMEN or NIT-AMEN . In conclusion, regression equations developed from broiler measurements or from analyzed nutrient composition proved adequate to reliably predict the DE of commercially available corn hybrids for growing pigs. [ABSTRACT FROM AUTHOR]

Companion animals play an important role in our lives and are now considered to be and treated as family members in a majority of households in the United States. Because of the high number of pets that now exist, an increasingly stronger pet-human bond, and the importance placed on health and longevity, the pet food industry has realized steady growth over the last few decades. Despite past successes and opportunities that exist in the future, there are also challenges that must be considered. This review will present a brief overview of the current pet food industry and address some of the key issues moving forward. In regards to companion animal research, recent advances and future needs in the areas of canine and feline metabolism, aging, clinical disease, and the gut microbiome using molecular and high-throughput assays; chemical, in vitro, and in vivo testing of feed ingredients; and innovative pet food processing methods is discussed. Training the future workforce for the pet food industry is also of great importance. Recent trends on student demographics and their species and careers of interest, changing animal science department curricula, and technology's impact on instruction are provided. Finally, the sustainability of the pet food industry is discussed. Focus was primarily placed on the disconnect that exists between opinions and trends of consumers and the nutrient recommendations for dogs and cats, the desire for increasing use of animal-based and humangrade products, the overfeeding of pets and the pet obesity crisis, and the issues that involve the evaluation of primary vs. secondary products in terms of sustainability. Moving forward, the pet food industry will need to anticipate and address challenges that arise, especially those pertaining to consumer expectations, the regulatory environment, and sustainability. Given the already strong and increasingly dynamic market for pet foods and supplies, an academic environment primed to supply a skilled workforce, and continued industry support for basic and applied research initiatives, the future of the pet food industry looks very bright. [ABSTRACT FROM AUTHOR]

The article presents several abstracts on topics related to animal nutrition and reproduction including mineral supplementation in pasture-based beef for animals, use of mineral nutrition on reproduction, and impact of vitamin and mineral status on beef cattle immune function and health.

This study was conducted to investigate the effects of dietary complexity and l -Thr supplementation on energy and nutrient utilization in nursery pigs. Thirty-two nursery pigs (7.23 ± 0.48 kg) were randomly assigned to a 2 × 2 factorial treatment arrangement based on diet complexity (complex vs. simple) with different levels of l -Thr supplementation. The complex diet contained animal protein sources (e.g., fish meal and plasma) and a dairy product (e.g., dried whey) to mimic a conventional nursery diet. The simple diet was formulated with corn, wheat, and soybean meal. Both diets were supplemented with l -Thr to contain either 100% or 115% (SUP Thr) of the estimated standardized ileal digestible Thr requirement for 9 kg body weight pigs (NRC, 2012). The pigs were individually housed in metabolism crates and fed an experimental diet ad libitum for a 7-d adaptation period and 5 d of total but separate urine and fecal collection. On day 14, all pigs were euthanized to determine body composition. The diet complexity, l -Thr supplementation, and their interactions were considered main effects. Pigs fed the complex diet tended to exhibit greater (P < 0.10) apparent total tract digestibility (ATTD) of ash and urinary energy output than those fed the simple diet. The complex diet had greater (P < 0.05) digestible energy and net energy contents than the simple diet. Furthermore, the complex diet-fed pigs had lower (P < 0.05) plasma urea nitrogen concentration on day 14 than simple diet-fed pigs. The SUP Thr decreased (P < 0.05) ATTD of acid detergent fiber but trended (P < 0.10) toward a decrease in urinary nitrogen (N) output and an increase in N retention and body N mass. In conclusion, the simple diet for nursery pigs had lower digestible and net energy contents than a complex diet. The SUP Thr can improve N utilization and body protein deposition, irrespective of diet complexity. [ABSTRACT FROM AUTHOR]