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During this centennial year of the American Society of Animal Science (ASAS), it is of interest to look back over the history of our Society and, in particular, to the many contributions made by researchers in the area of swine nutrition. A great number of basic and applied research studies involving the nutrition of weanling, growing, and finishing pigs, and gestating and lactating sows have been conducted by swine nutritionists during the past 100 yr. Most of these studies were conducted at universities by animal scientists or by the graduate students under their leadership. Others were conducted by nutritionists in the feed and pharmaceutical industries and government scientists at ARS/USDA research centers. Contributions were also made by animal scientists beyond our borders. Much of the research was published in the Journal of Animal Science during its 66 yr of existence. Before the first issue of the journal was published in 1942, some of the earlier studies were reported in the Proceedings of the Annual Meeting of the Society of Animal Production, the forerunner of ASAS. These research studies have progressively led to a better understanding of the role and utilization of dietary energy, protein, AA, carbohydrates, fats, minerals, and vitamins by pigs and have helped to quantify the nutrient requirements of pigs for various stages of growth, for sows during gestation and lactation, and to a limited extent, for boars. Determining the nutritional value of a wide array of feedstuffs, evaluating feeding strategies, and assessing the value of growth-promoting and carcass-enhancing agents have been important research contributions as well. To identify the particular studies that were among the most instrumental in contributing to our present knowledge of swine nutrition is, to say the least, a daunting assignment. To aid in this task, a survey of swine nutritionists was conducted in which they were asked to identify and rank the 10 most significant findings in swine nutrition during the past 100 yr. The results of that survey are presented in this paper. [ABSTRACT FROM AUTHOR]

Forage-animal production agriculture is implementing infrastructure changes and management strategies to adjust to increased energy-related costs of fuel, feed grains, fertilizers, and seeds. The primary objectives of this position paper are to assess future research and extension scientific needs in forage utilization, financial support for the discipline, and changing status and number of scientists. A survey questionnaire returned from 25 land-grant universities in the eastern half of the United States rated the top 4 research needs as 1) pasture systems and efficiency of production; 2) interfacing with energy concerns; 3) forage cultivar evaluations and persistence; and 4) environment impacts. Plant-animal future research needs at 11 USDA-ARS regional locations are targeted at sustainable management and improved livestock performance, ecophysiology and ecology of grasslands, environment impacts, and improved technologies for nutritive value assessments. Extension scientists from 17 southern and northeastern states listed the top 3 needs as forage persistence, soil fertility and nutrient management, and pasture systems and efficiency of production. Grant funds currently provide more than 40% of land-grant university research and extension efforts in forage utilization, and scientists estimate that this support base will increase to 55 to 60% of the funding total by 2013. Reduced allocation of state and federal funding has contributed to a reduction in the number of full-time equivalent (FTE) scientists engaged in forage utilization research and extension activities. The current 25 state FTE conducting research number about 2.8 per state. This includes 10 states with >3, 11 states with <2, and 3 states with <1 FTE. Increased interest in cellulosic energy, climate change, and environmental impact may offer new opportunities for these FTE to participate in integrated cross-discipline research Extension programming, and technology transfer methods will change to accommodate reduced funding but with increasing numbers of novice, recreation-oriented landowners. [ABSTRACT FROM AUTHOR]

The article presents abstracts from papers related to animal behavior that were published in the February 2005 issue of the "Journal of Animal Science." The paper "Characteristics and Potential Nutritive Value of Sagebrush-Grassland Vegetation Collected From Sites Continuously Grazed, Rested for One Year and One Year Post-Disturbance," by R. Weston, R.A. Olson, S.L. Lake, J.D. Derner, G.E. Schuman and B.W. Hess, studied initial impacts of rangeland management practices on characteristics and nutritive value of native sagebrush-grassland vegetation. The paper "Resumption of Ovarian Cycling Activity and Breeding Performance of First-Calf Suckled Beef Cows Exposed to Mature Bull Urine," by S. Tauck, and N. Johnson, determined if continuous exposure to bull urine alters resumption of ovarian cycling activity or breeding performance of first-calf suckled beef cows. The paper "Assessing Storage of Wet Brewers' Grains With Straws," by M. Kennedy, J. Males and M. Keller, evaluated the ensiling properties of wet brewers' grain alone and with various levels of straw so it can be used as part of the sole ration for ruminants.

The article presents abstracts on veterinary medicine topics which include the effect of starch level in the growing phase on performance and carcass traits, nutrient digestibility in growing pigs fed with wheat-based diets supplemented with phytase and xylanase, and effect of starch and protein digestion rates on nitrogen retention in pigs.

The article presents abstracts of topics related to nutrition of dairy cattle which include the relationship between negative energy balance and mastitis in dairy cattle during early lactation, the use of the Rumensin Premix in dairy cows: factors influencing its effects on milk production and milk composition and pre-pubertal nutrition affects mammary development and first lactation performance depending on growth potential in dairy sheep.

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]

The article presents information about the honorary fellows of the American Society of Animal Science, 2005. Louis J. Boyd earned his B.S. in 1950 and M.S. in 1951 at the University of Kentucky and his Ph.D. in 1956 at the University of Illinois. Boyd was a scientist and extension specialist in dairy cattle reproduction in the Department of Dairy Science at the University of Tennessee (1956-1962) and Michigan State University (1963-1972). Harold (Skip) Hintz is Professor of Animal Science at Cornell University. Hintz received his B.S. in animal science from the Ohio State University (1959) and his M.S. (1961) and Ph.D. (1963) in animal nutrition from Cornell University. Hintz recognized international authority on equine nutrition and is the author of more than 190 peer-reviewed scientific papers, mostly on equine nutrition, but also on the nutrition and metabolism of companion and exotic animals. Hintz's nutrition and management courses have a combined enrollment of 400 students per year.

This paper reviews results of studies on effects of fetal programming and maternal nutrition during pregnancy on growth, efficiency, carcass, muscle, and meat quality characteristics of cattle. It includes results from our Australian Beef Cooperative Research Centre studies on factors such as chronic severe nutritional restriction from approximately d 80 of pregnancy to parturition and/ or throughout lactation used to create early-life growth differences in the offspring of cows within pasture-based systems and the effect of these treatments on production characteristics to 30 mo of age. Fetal programming and related maternal effects are most pronounced and explain substantial amounts of variation for growth-related production characteristics such as BW, feed intake, carcass weight, muscle weights, meat yield, and fat and bone weights at any given age but are less evident when assessed at the same BW and carcass weight. Some effects of maternal and early-life factors in our studies were evident for efficiency traits but fewer affected beef quality characteristics at 30 mo of age, explaining only small amounts of variation in these traits. It is difficult to uncouple maternal nutritional effects specific to prenatal life from those that carry over to the postnatal period until weaning, particularly the effects of maternal nutrition during pregnancy on subsequent lactational performance. Hence, experimental design considerations for studying fetal programming effects on offspring during later life are discussed in relation to minimizing or removing prenatal and postnatal confounding effects. The relative contribution of fetal programming to the profitability of beef production systems is also briefly discussed. In this regard, the importance of health and survival of cows and calves, the capacity of cows to rebreed in a timely manner, and the efficiency with which feed and other resources are used cannot be overemphasized in relation to economics, welfare, and the environment. [ABSTRACT FROM AUTHOR]

Monensin is a common feed additive used in various countries, where 1 of the associated benefits for use in beef cattle is improved efficiency of energy metabolism by the rumen bacteria, the animal, or both. Modeling fermentation-altering supplements is of interest, and thus, it is the purpose of this paper to quantify the change in VFA profile caused by monensin dose in high-grain-fed beef cattle. The developmental database used for meta-analysis included 58 treatment means from 16 studies from the published literature, and the proportional change in molar acetate, propionate, and butyrate (mol/100 mol) as well as total VFA (mJW) with monensin feeding dose (mg/kg DM, concentration in the feed) was evaluated using the MIXED procedure (SAS Inst. Inc., Cary, NC) with the study treated as a random effect. The mean monensin dose in the literature database was 30.9 ± 3.70 mg/kg DM and ranged from 0.0 to 88.0 mg/kg DM. Mean DMI was 7.8 ± 0.26 kg DM/d, mean concentrate proportion of the diet was 0.87 ± 0.01, and mean treatment period was 42 ± 5.6 d. Results produced the following equations: proportional change in acetate (mol/100 mol) = -0.0634 (± 0.0323) x monensin (mg/kg DMV100 (P = 0.068), proportional change in propionate (mol/100 mol) = 0.260 (± 0.0735) x monensin (mg/kg DMV100 (P = 0.003), and proportional change in butyrate (mol/100 mol) = -0.335 (± 0.0916) x monensin (mg/kg DM)/100 (P = 0.002). The change in total VFA was not significantly related to monensin dose (P = 0.93). The results presented here indicate that the shift in VFA profile may be dose dependent, with increasing propionate and decreasing acetate and butyrate proportions (mol/100 mol). These equations could be applied within mechanistic models of rumen fermentation to represent the effect of monensin dose on the VFA profile in high-grain-fed beef cattle. [ABSTRACT FROM AUTHOR]

Nutritional requirements are typically estimated based on feeding trials with animals or birds offered several amounts of the critical nutrient(s). A nutrient response function is then fitted to data from the feeding trials. Modern computer techniques allow for a variety of functional forms to be used as nutrient response functions. However, the performance of these models is almost undistinguishable from a purely statistical perspective. This paper approaches the issue of determining nutrient requirements from an economic prospective. Crude protein amounts that would maximize profits were calculated for combinations of corn, soybean meal, and live broilers prices using several nutrient response models fitted to technical data from a trial with several balanced CP amounts fed to broiler chickens. Under certain combinations of input prices, differences between the models were between 1.5 and 3.0% CP. No model consistently predicted the greatest or least CP amounts or net profits, emphasizing that the (tangential) slopes of the models change at different rates over the range of nutrient (CP) amounts studied. Models providing adequate statistical fits to research data do not necessarily provide functions that are clearly most appropriate for maximizing producer profits. [ABSTRACT FROM AUTHOR]

Information about several papers discussed at the 2010 Triennial Growth Symposium held in Denver, Colorado is presented. Topics of the symposium include regulation of animal feed intake by hormonal mechanism, technique to improve animal growth and feed efficiency and the effect of leucine on protein synthesis in neonatal pigs. It states that the symposium intends to identify and explore new findings on the nutritional regulation of growth and development of domestic animals.

Over the years, numerous studies have investigated the mechanisms controlling nutrient availability and metabolism in the mammary gland and how dietary interventions can influence these processes. The development of in vivo and in vitro systems made it possible to explore the trafficking and metabolic fate of nutrients and how these are influenced by hormones. To improve the quality and safety of milk products, attention has focused on improving animal health in general and mammary gland health in particular and also on enhancing the milk content of natural bioactive milk components that promote the health of human neonates and adults. In the past, attempts to probe the relationship among nutrition, animal health, and animal products were limited to administering single dietary components and investigating their biochemical and metabolic effects. Today, we have genomics, proteomics, and related technologies that allow us to pursue more holistic investigational strategies. These new technologies are providing new insights into interactions among nutrition, lactation, and product quality. The aim of this paper is to review advances in nutritional support of mammary gland function and health as presented in 14 yr of Biology of Lactation in Farm Animals (BOLFA) meetings. [ABSTRACT FROM AUTHOR]

Use of a systems approach, as embodied in the computer simulation model of metabolism of a dairy cow, Molly (Baldwin, 2005), is ideal for teaching nutrition. This approach allows the overall complexity of the comprehensive system to be broken down into smaller manageable subunits that are easier to visualize. Quantitative interactions among nutrients supplied and metabolic production processes can be observed over extended time periods. Using Molly, under-graduate animal science students are able to observe detailed effects of changing dietary inputs, altering genetic milk production potential, and exogenously manipulating metabolism on metabolism of the whole cow. This paper demonstrates how Molly is used in the classroom to teach a systems approach to nutrition using example simulations. Three simulation examples demonstrate exercises examining effects of recombinant bovine somatotropin administration, dietary protein, and amino acid supplementation and nitrogen efficiency on milk production and cow metabolism. These and similar examples have been used to teach nutrition, metabolism, and lactation to undergraduate students for the past 20 yr. [ABSTRACT FROM AUTHOR]

The article presents abstracts from papers related to animal nutrition that were published in the February 2005 issue of the "Journal of Animal Science." The paper "Body Condition Score at Parturition and Effects of Postpartum Supplemental Fat on Metabolite and Hormone Concentrations of Beef Cows," by S. Laket, E. Scholljegerdes, V. Nayigihugu, R. Atkinson, E. Van Kirk, D. Rule, D. Hallford, G. Moss, and B. Hess, determined the effects of body condition score at parturition and postpartum lipid supplementation on blood metabolite and hormone concentrations. The paper "In-Vitro and In-Vivo Rumen Fermentation and Gas Production: Influence of Corn and Mineral Oils and Their Bloat Potential," B. Min and W. Pinchak, investigated the influence of mineral and corn oil on ruminal fermentation, gas production, and bloat potential in a series of in vitro and in vivo grazing studies. The paper "Fatty Acid Composition of Plasma, Medial Basal Hypothalamus, and Uterine Tissue in Primiparous Beef Cows Fed High-Linoleate Safflower Seeds," was presented by E. Scholljegerdes, D. Rule, U. Moss, and B. Hess.

The article presents abstracts from papers related to animal nutrition that were published in the February 2005 issue of the "Journal of Animal Science." The paper "The Effects of Early Weaning on Cow Performance and Grazing Behavior in the Intermountain West," by D.W. Bohnert, D.C. Ganskopp, D.D. Johnson and S.J. Falck, determined the influence of early weaning and traditional weaning on cow performance and grazing behavior within three pastures. The paper "Use of Green Fodder Produced in Hydroponic Systems As Supplement for Salers Lactating Cows During the Dry Season," by C. Rodriguez Muela, H.E. Rodriguez, O. Ruiz, A. Flores, J.A. Grado and C. Arzola, analyzed the productive and reproductive behavior of lactating salers cows with calf using the hydroponics green fodder as supplement. The paper "Long-Term Use of Low-Quality Forages in Beef Cow Nutritional Management: Effects on Productivity and Economics," by I. Wayment, R. Wiedmeier, K. Olson, D. Snyder and P. Schmidt, evaluated the use of LQF in the wintering diets of beef cows on a long-term basis regarding days of use per year and consecutive years of use.

The article presents abstracts from papers related to animal nutrition that were published in the February 2005 issue of the "Journal of Animal Science." The paper "Estimation of Undegradable Intake Protein Digestibility in Forages Using a Mobile Nylon Bag Technique," by J. Benton, J. MacDonald and M. Lamothe, used two ruminally and duodenally cannulated steers to estimate digestibility of undegradable intake protein of two forage types using a mobile bag technique. The paper "Combinations of Distiller's Grains, Gluten Feed, and Soy Hulls for Growing Cattle," by J. Sewell and L. Berger, evaluated co-products combinations compared to a program-fed corn based growing diet for feedlot cattle. The paper "Potential of Alimet Supplementation to Improve Growth and Reproduction of Beef Heifers Fed a Forage Diet," by E. Venable, M. Kerley and B. Miller, studied the importance of adequate growth rates by beef heifers. Supplementing rumen undegradable protein has been shown to enhance reproductive tract development in heifers.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 28, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Metabolizable Protein Effects on Ammonia Emissions and Nitrogen Excretion of Steers," by D.Panetta, W. Powers, and J. Russell. Protein degradability effects on N metabolism and NH3 emissions were evaluated. In experiment 1, eight steers were fed diets containing urea, soybean meal, or soybean meal and urea. In experiment 2, nine steers were fed diets containing 0, 12, or 24% distillers dried grain with solubles. Another paper discussed is "Ruminal Fermentation of 15N-Labeled Alfalfa Hay N Fractions In Vitro," by A. Melgart and A.N. Hristov. The objective of this study was to compare the ruminal in vitro rate and extent 15N-labeled alfalfa hay N fractions. Nitrogenous fractions from green house-grown alfalfa hay were isolated and incubated in vitro with mixed ruminal populations.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 28, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Effect of Stocking Density and Fence Line Barrier on the Behavior of Dairy Cattle," by J.M. Huzzey, P. Valois, T.J. DeVries, M.A.O. von Keyserlingk, and D.M. Weary. The objectives of this study were to evaluate the effect of using a headlock or a post-and-rail barrier on the behavior of dairy cows, and to determine how this effect interacts with stocking density. Thirty-six lactating Holstein cows were divided into four groups, two assigned to each barrier design. Groups were followed for 40 d and then switched to the alternate barrier for a subsequent 40 d. Another paper discussed is "The Cornell Net Carbohydrate and Protein System: An Evolving Model," by T. Tylutki and D. Fox. The Cornell Net Carbohydrate and Protein System, a cattle nutrition model, has been under continuous development since the early 1980s. The upcoming version has undergone a comprehensive review with the addition of recent biological advances.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 28, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Fate of Supplemental Escherichia coil Phytase in the Digestive Tract of Young Pigs," by A.R. Pagano, K.R. Roneker, and X.G. Lei. The objective of this study was to determine the functional site of a supplemental E. coli phytase and its impact on phosphorus contents of digesta in different segments of the gastrointestinal tract of pigs. A total of 18 weanling pigs were allotted to three groups and were fed a low-P corn-soy basal diet (BD), BD + E. coli AppA2 phytase, or BD + inorganic P for 4 wk. Another paper discussed is "The Effect of Wheat Variety and Enzyme Supplementation on Pig Performance," by M.E.E. McCann, K.J. McCracken and P.H. Simmins. Although wheat is a major component of many pig diets, it has been reported to be the most variable in terms of chemical composition and nutritive value. This variation arises from a number of factors, including variety. Wheat nutritive value can also be affected by non starch polysaccharide content, the presence of the IB/IR gene and endosperm hardness.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Effect of Cooked Molasses Block Supplementation and Flax on Newly Received Calf Performance," by D. Larson, M. Bauer, G. Lardy and J. Stewart. One hundred forty-four crossbred steers were used to evaluate the effect of supplemental cooked molasses blocks with and without flax on newly received calf health and subsequent performance. The authors hypothesized that calves would consume blocks, thereby, increase nutrient intake during periods of low feed intake, which typically occur after weaning. Steers were assigned randomly to one of three treatments: control, block without flax and block including ground flax. Another paper discussed is "Effects of Winter Growing Program on Visceral Organ Mass and Oxygen Consumption in Beef Steers," by M. McCurdy, C. Krehbiel, G. Horn and J. Wagner. The purpose of this study was to investigate the effects of winter growing program on visceral organ mass and oxygen consumption. A total of 46 steers were utilized for the experiment. Four steers were harvested at the beginning of the experiment.

This article presents abstracts of various papers related to animal nutrition management and environment, that were presented during the symposium held on July 26, 2005, Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science and the Canadian Society of Animal Science. One of the papers presented is "Assessment of Dairy Farm Management Practices Through Internet Connections," by J.D. Ferguson and others. A major challenge in the dairy industry is transfer of information and technology to dairy farms. Extension systems have been reduced in size due to costs to maintain extensive systems. This reduces the ability to deliver technical assistance to many local dairy farms. Another paper discussed is "Effects of Feeding Varying Concentrations of Dry Distillers Grains With Solubles to Finishing Steers on Performance and Odorant Emissions," by C. Benson, K. Tjardes and C. Wright. Distillers grains are becoming more prevalent as a feedstuff, with dried distillers grains plus solubles being the predominant form. This trial was designed to determine if feeding increasing concentrations of DDGS affects finishing steer performance and odor emissions.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Development of an In Vitro Technique to Monitor the Fate of True Proteins of Feedstuffs in the Rumen," by A.A. Sadeghi and P. Shawrang. An integrated artificial rumen and electrophoretic technique were used to develop an in vitro technique to monitor the fate of true proteins of feedstuffs in the rumen. The objective was to adapt an in vitro procedure to obtain simulated rumen fluid and many residue at different incubation times that could be analyzed for true protein patterns by using SDS-PAGE technique. Another paper discussed is "Amino Acid Content of Residues From In Vitro and S. Griseus Incubations," by D.A. Ross and M.E. Van Amburgh. The degradability of ruminant feed proteins has been measured using in vitro and protease procedures but without comparative amino acid (AA) contents of the residues. The objective of this study was to evaluate the AA contents of the residues following a 24-hr IV fermentation and a comparative S. griseus incubation at time points designed to correspond to the protein degradation observed in the IV fermentation for twelve feeds.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Nutrient Digestibility in Microbial Phytase Supplemented Corn-Soybean Based Diets in Two Phases of Growing Pigs," by H. Krebs, C.T. Kadzere, Z. Liu, and E. van Heugten. Phytate phosphorus (P) makes up 40 to 90% of P in cereal grains and in oilseeds and is unavailable to swine except when supplementary phytase is in the diet. In a 4 x 4 CRD study, 16 male castrated pigs were assigned to four homogenous groups of four animals each to evaluate the effects of microbial phytase on nutrient digestibility in pigs in Phase I and in Phase II. Each group was fed one of four diets differing only in P, calcium and phytase content. Another paper discussed is "Effect of Phytase Activity of the Diets on the Faecal and Urinary Phosphorous Excretion in Adult Roosters," by J. Tossenberger, L. Babinszky and I. Kuhn. The effect of phytase on phosphorus (P) excretion of poultry has been customarily determined in studies with intact birds based on collection of excreta. By using cannulation techniques, it is possible to measure faecal and urinary P excretion separately.

This article presents abstracts of various papers related to ruminant nutrition, that were presented during the symposium held on July 26, 2005, Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science and the Canadian Society of Animal Science. One of the papers presented is "Effect of Dietary Copper Supplementation on Fatty Acid Profile of Muscle, Mesenteric, and Subcutaneous Adipose Tissue in Goat Kids," by E. Ellis, W. Bergen, S. Solaiman and K. Cummins. A feeding trial was conducted to evaluate the effect of dietary copper supplementation at 0, 100 and 200 mg/d above basal intake on relative amounts of fatty acids in various tissue depots of goats. The effect varied with tissue and affected different fatty acids in different tissues. Another paper presented is "Vitamin E Improves the Number of Transferable Embryos and Born Lambs in Super-Ovulated Ewes," by H. Luo, S. Zhu and Z. Jia. The effect of Vitamin E on the multiple ovulation embryos transfer was studied in two experiments. Fourteen ewes were divided into two groups in Exp 1, and Vitamin E was added 400mg/day to the diet and 16 times higher than the NRC standard in the treatment group.

This article presents abstracts of various papers on amino acids and dietary restrictions related to nonruminant nutrition, that were presented during the symposium held on July 26, 2005, Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science and the Canadian Society of Animal Science. One of the papers discussed is "Development of the Enzymes of Homocysteine Metabolism From Birth Through Weaning in the Pig," by D.M. Ballance and J.D. House. In humans, non-human primates and rats, cysteine (CYS) is considered to be a conditionally indispensable amino acid. Developmental delays in the activity levels of a key enzyme from the transulphuration pathway, cystathionine-B-synthase and cystathionine-y-lyase may contribute to the limitation in endogenous CYS availability. Another paper discussed is "Impact of spray-dried plasma form and feeding duration on broiler performance," by J.M. Campbell, J.D. Crenshaw and others. During the experiment, broilers developed necrotic enteritis and tissue cultures were positive for Escherichia coli and Salmonella, Addition of SDP to the feed improved feed intake, and feed efficiency for each time period of the study.

This article presents abstracts of various papers on feedstuffs and processing related to nonruminant nutrition, that were presented during the symposium held on July 26, 2005, Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science and the Canadian Society of Animal Science. One of the papers discussed is "Productive Performance of Early-Weaned Pigs Fed Different Vegetable Protein Sources," by D.G. Valencia, M.P. Serrano and others. A trial was conducted to test the influence of the inclusion of several vegetable protein sources in the diet on productivity of young piglets in the absence of in-feed growth promoters. The protein source tested supplied in all cases 5.5% of the total dietary protein. Another paper discussed is "Effect of Ground Flaxseeds on the Performance and Carcass Traits of Finishing Pigs," by K. Saski, S.K. Baidoo and Q. Yang. The objective of this study was to determine the effects of dietary supplementation of ground flaxseeds on the growth performance and carcass traits of finishing pigs.

This article presents abstracts of various papers related to ruminant nutrition of cows, that were presented during the symposium held on July 26, 2005, Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science and the Canadian Society of Animal Science. One of the papers presented is "Dietary Cation-Anion Difference and Dietary Protein Effects on Performance and Acid-Base Status of Dairy Cows in Early Lactation," by W. Hu, M.R. Murphy and others. The objective was to examine the effects of dietary cation-anion difference with different concentrations of dietary protein on performance and acid-base status in early lactation cows. Another paper discussed is "Utilization of Phosphorus in Lactating Cows Fed Varying Amounts of Phosphorus and Sources Of Fiber," by Z. Wu. Increasing dietary P increased fecal Phosphorus (P) excretion. Partial substitution of soyhulls for alfalfa hay did not affect milk production, but resulted in less fecal P excretion.

This article presents abstracts of various papers related to the methodology and modeling of ruminant nutrition, that were presented during the symposium held on July 26, 2005, Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science and the Canadian Society of Animal Science. One of the papers presented is "Influence of Fermentation Method on NDF Degradation Parameter Estimates," by D. Bossen, D. R. Mertens and M.R. Weisbjerg. Effect of three methods of fermentation on degradation parameters was studied using feeds ground to different sizes. Corn silage, grass silage, barley grain, sugar beet pulp, and rape seed cake were ground using a shear mill. Another paper discussed is "Measurement of Volatile Fatty Acid Interconversion As a Means to Study the Role of Thermodynamics in the Control of Fermentation," by E. Ungerfeld, B. Bequette, S. Owens and R. Kohn. The molar ratios of volatile fatty acids observed in the rumen may result in part from thermodynamic constraints on rumen fermentation. If certain pathway branches become infeasible because of the buildup of end products, fermentation may shift momentarily to other pathways, keeping the profile of end products in equilibrium.

This article presents abstracts of various papers related to ruminant nutrition, that were presented during the symposium held on July 26, 2005, Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science and the Canadian Society of Animal Science. One of the papers presented is "Effects of Omnigen-AF on Milk Production and on Lactation Persistence in a Commercial Dairy Setting," by J. Chapman, S. Pintenney, J. Verano and others. The goal of this study was to evaluate effects of feeding OmniGen-AF, a commercially available feed additive, on milk production and persistence of milk yield during a 60-day field trial. Effects of the two treatments on milk production were assessed statistically with a model which included pre-experiment milk production, days in milk, and lactation number as co-variates. Another paper discussed is "Effect of Increasing Oil From Distillers Grains or Corn Oil on Lactation Performance," by C. Leonardi, S. Bertics and L. Armentano. The objective of this study was to evaluate lactation production response of dairy cows fed distillers dried grains with added solubles.

This article presents abstracts of various papers related to the nutrition management in animals, that were presented during the symposium held on July 26, 2005, Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science and the Canadian Society of Animal Science. One of the papers presented is "Electronic Identification of Young Lambs With Mini-Bolus and Effects on Intake and Digestibility During Fattening," by J. Ghiradi, G. Caja, C. Flores and D. Garin. Lambs sucked from their mothers until wk 5 or wk 6, and were intensively fattened thereafter. Growth rate, bolus retention and health status were recorded weekly. Retrieval and fore-stomachs location of cylindrical ceramic mini-boluses at slaughter were also recorded. Another paper discussed is "Multivariate Factor Analysis of Electrical Conductivity in Dairy Cattle," by N.P.P. Macciotta, M. Mele, R. Steri and P. Secchiari. Electrical conductivity of milk is an indicator trait for mastitis and it may be considered as a potential breeding goal for genetic programs, even if an accurate detection of affected animals still represents a problem.

The article presents abstracts of various research papers related to ruminant nutrition, that were presented during the symposium held on July 25, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers titled "Genotype and Feed Effects on Annual Milk Production and Reproduction of Grazing Dairy Cows," decision rules for supplementing North American and New Zealand Holstein Friesians were investigated over two years using 57 cows fed well on pasture throughout lactation and receiving 0,3 or 6 kg concentrate DM/cow/d. Cows calved in spring as a single herd and were individually fed a grain supplement. Treatments were balanced at the start of each season for estimated genetic merit, and for sire and live weight within genotype. The 2 x 3 factorial design was analysed by the REML procedure of Genstat. No significant genotype x diet interaction was detected for any production response. However, genotype responses were more divergent at the highest level of supplementation. Over the 291-d lactation, milk yield and yield of fat and protein responded linearly, and production efficiency quadratically to supplementation.

The article presents abstracts of various research papers related to ruminant nutrition, that were presented during the symposium held on July 25, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. In one of the papers titled "A Review of the 2001 dairy Cattle NRC Protein and Amino Acid Model: A European Perspective," NRC 2001 protein and amino acid model was tested using data from eight production experiments with dairy cows conducted using change-over designs. The experiments included a total of 72 selected to represent a wide range in feed intake, milk production and strategies to manipulate metabolizable protein (MP) intake. Grass silage, rolled barley and rapeseed feeds were the most typical forage, energy and protein supplements; that is the test data consisted of diets not typically used in the U.S. It was concluded that the NRC 2001 amino acid model is a significant step forward in achieving a more precise feeding for N. Methodological aspects in determination parameters used to estimate MP supply will be discussed.

The article presents abstracts of various research papers related to animal nutrition that were presented during the symposium held on July 25, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. In one of the papers titled " Effects of Bio-Mos and Carbadox on Gastrointestinal pH, Organ Weight and Morphology of Nursery Pigs," a 3-week experiment was conducted to evaluate the effect of a mannan oligosaccharide product and antibiotic on gastrointestinal characteristics of pigs. Thirty pigs were weaned at an average of 21.2 d and 5.95 kg BW. At weaning, six pigs were euthanized for gastrointestinal sample collection, while the remaining 24 pigs were randomly allocated to one of four dietary treatments. The experiment was conducted as a 2 x 2 factorial arrangement, with the factors being 0 or 0.2% Bio-Mos and 0 or 55 ppm carbadox. Twelve pigs, representing three pigs per treatment, were euthanized on each of 2 days, 7 or 21 d post-wean.

The article presents abstracts of various research papers related to nonruminant nutrition that were presented during the symposium held on July 24-28, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. In one of the papers titled "Effect of Dietary Mannan-Oligosaccharides and Organic Zinc on Growth Performance and Prevalence of Post-Weaning Diarrhea in Piglets," The efficacy of Mannan-oligosaccharide (MOS) and organic zinc (Zn) to enhance performance and prevent diarrhea in early-weaned pigs was evaluated. A total of 128 piglets, weaned at 20±2 days were housed in 32 pens following a complete randomized design. Animals received four dietary treatments: a control diet to which 0.2% of a commercial source of MOS, 0.08% organic Zn or both additives were added. The experiment lasted for 5 weeks including a pre-starter period of two weeks and a starter period of three weeks. Results suggested that the use of MOS or organic Zn can both improve the adaptation of the weaning pig to the dry food, thus reducing the incidence of post-weaning diarrhea, This was also manifested by an increase in the feed efficiency ratio.

The article presents abstracts of various research papers related to nutrition of beef cattle that were presented during the symposium held on July 24-28, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. In one of the papers titled "Effect of Clinoptilolite Zeolite on Cattle Performance and Manure Nitrogen," a summer feedlot trial was conducted from May to September using 96 crossbred yearling steers to evaluate effects of adding clinoptilolite zeolite at 1.2% of the diet on steer performance and N removed in manure. Steers were stratified by weight and assigned randomly to 12 pens and one of two treatments. Treatments were control diet with 0% zeolite clay or treatment diet with 1.2% clinoptilolite zeolite clay. Diets consisted of 62.5% dry rolled corn, 25% wet corn gluten feed, 7.5% alfalfa hay and 5% supplement. Nitrogen intake was calculated using analyzed dietary N concentration for each feedstuff and total DMI.

The article presents abstracts of various research papers related to ruminant nutrition that were presented during the symposium held on July 24-28, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers titled "Effect of Feeding Medium Chain Triglycerides on Calf Growth, Insulin Responsiveness and Body Composition," determined the effects on the growth, body composition, and response to an insulin challenge in calves fed isocaloric, isonitrogenous diets that varied in the amount and type of fatty acid. Thirty-six calves were assigned to a randomized block design with three dietary treatments, ten calves per treatment and a baseline group of six calves. Animals were reared from birth to 88.1 kg live bodyweight (BW). Three different milk replacer-based diets were designed to deliver less than 2% of the lipid as medium chain triglycerides (MCT), 32% MCT in the form of caprylate and 32% of fatty acids primarily in the form of laurate from coconut oil.

The article presents abstracts of various research papers related to nonruminant nutrition that were presented during the symposium held on July 24-28, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. In one of the papers titled "A Strawberry Flavor in Drinking Water and Feed Improves Water Intake and Growth of Pigs at Weaning," a two-phase trial was conducted to study the effects of a strawberry flavor and a high intensity sweetener (HIS) in drinking water and feed on the performance of weanling pigs. Eighty 21 day-old Landrace piglets were distributed in 24 pens with three or four pigs, each provided with an independent water container. In phase I, all pigs were offered the same unflavored diet for a period of 14 days but four treatments were administered in the water: either with no additions, or with flavor, with HIS or both flavor and HIS. In phase II, the animals in each treatment were divided into two groups receiving unflavored water but offered either flavored or unflavored feed. Overall, the results suggested that water intake after weaning is encouraged with the use of flavor, and that this has beneficial effects on piglet performance.

Using both in vitro and in vivo approaches, numerous studies have provided evidence that μ-calpain is responsible for postmortem proteolysis. This paper reports the effect of overexpression of calpastatin on postmortem proteolysis in transgenic mice. Transgenic mice (n = 8) with a human calpastatin gene, whose expression was driven by the human skeletal muscle actin promoter, were killed along with control nontransgenic littermates (n = 5). Hind limbs were removed and stored at 4°C, and muscle samples were dissected at 0, 1, 3, and 7 d postmortem and analyzed individually. At time 0, active human calpastatin was expressed in transgenic murine skeletal muscle at a level 370-fold greater (P < 0.001) than calpastatin in control mice. Although the native isoform of this protein was degraded with storage, at 7 d postmortem, approximately 78% of at-death activity remained, indicating that degraded calpastatin retains activity. Calpain (μand m-) expression was unaffected (P > 0.05) by the transgene as assessed by immunoreactivity at d 0. Over 7 d, 33% of at-death 80-kDa isoform immunoreactivity of μ-calpain was lost in transgenics compared to an 87% loss in controls, indicating that autolysis of μ-calpain was slowed in transgenic mice. Desmin degradation was also inhibited (P < 0.05) in transgenics when compared to controls. Control mice lost 6, 78, and 91% of at-death native desmin at 1, 3, and 7 d postmortem, respectively; conversely, transgenic mice lost only 1, 3, and 17% at the same times. A similar trend was observed when examining the degradation of troponin-T. Interestingly, m-calpain seemed to undergo autolysis in control mice, which in postmortem tissue is indicative of proteolysis. Further investigation revealed that both μand m-calpain are active postmortem in normal murine skeletal muscle. In conclusion, a high level of expression of active calpastatin was achieved, which, by virtue of its inhibitory specificity, was determined to be directly responsible for a decrease in postmortem proteolysis. [ABSTRACT FROM AUTHOR]

In this paper, the status of the analytical technologies for assaying animal antinutritional compounds, such as raffinose oligosaccharides, pentosans, phytic acid, and glucosinolates, is reviewed in terms of selectivity, sensitivity, and sample throughput. The implementation of simplified sample preparation schemes, use of novel separation approaches, and alternate detector technologies are discussed. The challenges and opportunities posed by these assays are highlighted along with the recommendations for best analytical practices. [ABSTRACT FROM AUTHOR]

The article reports that the U.S. Food & Drug Administration appointed a Task Force to evaluate the animal-health and public-health implications of feed-additive usage of antibiotics. The FDA Task Force reportedly concluded that some antibiotic-sensitive and antibiotic-resistant bacteria of animal origin could be pathogenic to humans. It adds that FDA advisory committee marked restrictions on the use of penicillin and tetracyclines but no changes in the usage of sulfaquinoxaline.

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 article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Effects of Food and Water Intake on Variation in Deal Digesta Viscosity Among Dogs Fed a Maintenance Diet," by C. Dikeman and G Fahey. A two-period crossover design experiment was conducted to address effects of food and water intake on ileal digesta viscosity among dogs. Six ileal cannulated dogs, average weight of 26.0 kg, were fed during an initial 6-d adaptation phase up to individual energy requirements. Another paper discussed is "Canine Diet Matrices Affect Digesta Viscosity In Vitro and Ileal Viscosity In Vivo," by C. Dikeman and G. Fahey. Two experiments were conducted to determine the effects of canine diet matrix on ileal digesta and simulated digesta viscosity in vitro. Three canned diets containing either carageenan, guar gum, or soybean hulls + cellulose and three dry extruded diets containing rice bran, wheat bran, or soybean hulls, were fed to 6 ileal cannulated dogs in a 6 x 6 Latin square design.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Near Infra-Red Reflectance Spectroscopy for Prediction of Amino Acids in Feed Ingredients Leads to Important Cost Savings in Diet Formulation," by J. Goodson, D. Hoehier, J. Fontaine and others. Near infrared reflectance spectroscopy calibrations used to predict amino acid levels in feed ingredients can be used to allow swine feed formulators to reduce safety margins in formulation programs. Reduction of these safety margins for amino acids allows the production of feeds which meet animal requirements for protein and amino acids without supplying excessive levels of either. Another paper discussed is "Use of Rice in Substitution of Corn in Diets for Young Pigs," by B. Vicente, D.G. Valencia, R. Lazaro and others. The authors studied the influence of feeding rice on the ileal digestibility of dry matter, organic matter, gross energy and starch and the morphology of the ileum of piglets at 37 d of age. The control diet was a complex diet without in-feed growth promoters and included 50% cooked corn.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Fatty Acid Composition in Rumen Bacteria Isolated From Ruminal and Duodenal Digesta," by B. Vlaeminck, R.J. Dewhurst, and V. Fievez. The objective of this study was to compare the fatty acid composition in rumen bacteria isolated from the liquid and solid phase of the rumen and duodenal digesta from dairy cows fed diets varying in forage:concentrate. Another paper discussed is "Development of an In Vitro Method to Estimate Fat Digestibility in the Small Intestine of Ruminants," by T. Glindemann, K.H. Suedekum and E. Wisker. Supplementation of dairy cow diets with rumen-protected fat (RPF) has consistently increased yields of milk and milk fat, and may also improve reproductive performance of ruminants. Although one important feature of the effects of RPF is digestibility in the small intestine, this variable is only very infrequently reported. The objective of the current study was therefore to develop an in vitro method to estimate the digestibility of fats in the small intestine of ruminants by closely mimicking the chemical and physical conditions within the small intestine.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Studies on Causes of Sow Disposal at Different Parities of Large White Sows," by J. Arango, I. Misztal, S. Tsuruta, M. Culbertson, and W. Herring. Different reasons of sow removal (RR) at consecutive parities were analyzed with 13,838 records of Large White sows. Data were from seven pure-line farms having, on average, 5.9% unknown RR. Three traits were defined, each corresponding to a classification of RR as a five-category trait, according to parity of removal. Univariate and multivariate linear and threshold models were implemented via animal or sire models. Another paper discussed is "Relations Between Lactation-, and Slaughter/Carcass Traits in Pigs," by E.F. Knol, D.T. Prins, and R. Bergsma. Pork industry benefits from uniformity. Meat companies start to tighten weight grids and implement bonus/malus systems for carcass grading. The authors were interested in the relation between early development and final slaughter traits in pigs.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Impact of Rumensin Premix on Reproductive Performance in Dairy Cows," by T. Duffield, S. LeBlanc, D. McClary, H. Green, and J. Wilkinson. Reproductive data were gathered from 966 Holstein dairy cows in a field trial at 9 sites in North America. Primiparous and multiparous cows were randomized to receive 0, 8, 16, or 24 ppm of monensin in the diet from 3 weeks before expected calving, through lactation, into the dry period and for 7 days into the subsequent lactation. At all sites the voluntary waiting period was 50 days in milk (DIM) and breeding was stopped at 200 DIM. Another paper discussed is "Effects of a Yucca Schidigera Extract on Microbial Metabolism in Continuous Culture of Rumen Contents," by J. Clark, T. Miller-Webster, W. Hoover, and B. Clyburn. Two experiments were conducted using dual flow continuous cultures to evaluate the effect of a Yucca schidigera extract product, Micro-Aid on microbial metabolism and efficiency. In both experiments fermenters were maintained at constant temperature, solids and liquid dilution rates.

The article presents abstracts of various papers related to animal feeding that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Development of an On-Farm Feed Management Assessment Tool for Use With Dairy Comprehensive Nutrient Management Plans," by L. VanWieringen, J. Harrison, R. Kincaid, A. Hristov and others. A requirement of the U.S. Environmental Protection Agency's guidelines for concentrated animal feeding operations in 2003 is to develop a nutrient management plan. One form of a nutrient management plan is a comprehensive nutrient management plan that is described in the NRCS Field Office Technical Guide. Another paper discussed is "Evaluation of Whole-Farm Nutrient Balances on a Commercial Dairy Operation," by T. Nennich, J. Harrison, D. Davidson and others. Evaluations of whole-farm nutrient balances are an important part of understanding nutrient management on dairy operations. Whole-farm nutrient balances supply specific information as to the flow of nutrients on dairy operations and provide data as to whether or not dairy operations are net importers or exporters of nutrients.

The article presents abstracts of various papers related to animal nutrition that were presented during the symposium held on July 27, 2005 in Cincinnati, Ohio, which was organized by the American Dairy Science Association, the American Society of Animal Science, and the Canadian Society of Animal Science. One of the papers discussed is "Genetic Background and Phosphorus Nutrition Affect Bone Strength and Gene Expression in Young Pigs," by L. Hittmeier, R. Lensing, L. Grapes, M. Rothschild, and C. Stahl. Phosphorus (P) is essential to bone growth and turnover; however, little research has focused on the genetic mechanisms controlling P utilization. In this study, 36 guts from six litters were sired by two lines known differ in bone structure. Pigs were assigned to three dietary treatments: P adequate, repletion, or P deficient. Another paper discussed is "Dietary Selenium Sources in Swine: Maternal Transfer to Embryos," by M.E. Fortier, H. Quesnel, J.F. Bilodeau and others. This project aimed to determine the effect of selenium(Se) as inorganic Na-selenite or organic Se-yeast on maternal Se transfer to embryos, embryonic antioxidant status and litter performance.