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A semi-hydroponic system was developed to assess canola (Brassica napus L.) root architectural traits. Four cultivars were grown under controlled conditions in germination paper rolls immersed in half-strength Hoagland's solution. Eight parameters, including total root length, total root surface area, average root diameter, tip number, total primary root length, total lateral root length, total tertiary root length, and basal link length, were analyzed using the WinRHIZO software after 7, 14, and 21 days. The results suggested that 14 days in the semi-hydroponic system were optimal for accurate root trait assessment, as clear differences were observed while maintaining ease of handling and scanning. [ABSTRACT FROM AUTHOR]

Canadian cow-calf producers are facing pressure to adopt management practices and technologies that help increase the economic and environmental sustainability, and public perception of beef production. Our aim was to describe technology adoption, management and record keeping practices in Canadian cow-calf herds, assess associations between herd attributes, productivity outcomes and adoption; and identify opportunities for improvement. Surveys from 131 Canadian cow-calf producers recruited through a national surveillance program were analyzed. Individual female records (80%) and feed testing (84%) were commonly reported as currently or occasionally used, followed by on-farm weigh scales (66%). Western herds were likely to utilize feed testing and nutritionists, ionophores, and growth promoting implants, while eastern herds commonly used reproductive technologies. Large herds (>300 cows) were more likely to adopt technologies that aid in data capture (i.e., weigh scales) and follow recommended practices (i.e., feed testing). Paper was the main record keeping format. Production records were commonly utilized for culling and replacement heifer selection. Technology use has increased across the country compared to previous surveys and producers are implementing practices to help increase production efficiency. However, there is an opportunity to increase use of technologies that support individual animal and herd data to help inform ranch decisions. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate whether characteristics of the first lactation (FL) curve of Iranian Holstein cows are associated with survival. Cows with least 10 test-days of milk production in their FL were used. The persistency of lactation (PL) and survival were estimated using a random regression model by restricted maximum likelihood with the ECHIDDNA software. We also used the Wood model to parameterize each individual lactation curve and then analyzed various curve characteristics using an animal model. The predicted breeding value (EBV) of the characteristics of the lactation curve of the cows from day 40 to 305 was predicted. The EBV of the production range (PR) and the slope of line in increasing phase (m40,Peak) of production curve of sires with higher survival EBV were lower than other sires (P < 0.05). The estimates of PL were independent of survival estimate. Therefore, the PR from 40th day after calving can be considered as a definition of PL because the lower the PR, the flatter is the milk production curve. Genetic evaluation of young bulls for survival needs the data of death or culling of their daughters. Therefore, the bulls can genetically be evaluated for survival according to the PL and m40,Peak of FL information of their daughters. [ABSTRACT FROM AUTHOR]

To date, no selective actions have been taken to improve milk traits in dairy donkeys, and the characteristics of the udder are not well defined in relation to the productive characteristics. This study aimed at increasing knowledge on Amiata dairy donkey body conformation, udder traits, and their relationship with milk yield and quality. Morphological, udder, and teat measurements and milk evaluations of 45 pluriparous jennies were carried out. The average wither height of the jennies was 126 cm and the chest girth was 148 cm; a large standard deviation of some body measurements was found. Forty-nine percent of the animals showed a moderately developed udder, while most of the jennies had symmetrical half-udders (96%) and the intermammary cleft was clearly visible in 53% of subjects. Correlation analysis indicated that bigger animals tend to have bigger udders, higher teat diameter, and greater distance between teat tips. A positive correlation between the teat length and the milk fat was found (p < 0.01), which suggests that jennies with longer teats have a better ability to release milk fat. The results of this paper may be useful to define the characteristics of the milking device and address selective choices of the animals. [ABSTRACT FROM AUTHOR]

Calf diseases remain a challenge for dairy producers from both an economic and welfare perspective. Genetically selecting for disease resistance in calves is a promising approach that could contribute to sustainable dairy farming. Genetic evaluations, however, require well-defined and consistently recorded phenotypes to be successful. Therefore, this study aimed to understand the current state of calf disease recording on Ontario farms. Calf disease records of respiratory illness and diarrhea were available from the national milk recording organization (Lactanet Canada, Guelph, Ontario, Canada) from 2009 to 2020. A case study was conducted to describe calf disease diagnoses and recording practices by surveying a subset of 13 Ontario dairy producers. The percentage of milk recorded farms that recorded calf respiratory illness and calf diarrhea increased from 2.6% in 2009 to 11.1% in 2020. Potential sources of data loss were identified along the information chain from farm to genetic evaluation database. Clear definitions and thresholds to diagnose calf disease, standard operating procedures for data recording, as well as a data transfer pipeline, which includes exchange formats, are needed to facilitate the inclusion of calf health traits in genetic evaluations. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lameness is the second most prevalent morbidity in North American feedlot cattle and is both an animal welfare and economic concern. Lameness accounts for 30%–40% of all feedlot treatments with greater than 70% being foot-related lameness (FRL). This review focused on foot rot (FR), digital dermatitis (DD), and toe tip necrosis syndrome (TTNS). While there are significant study-to-study differences regarding the prevalence of FR, DD, and TTNS, it is unequivocal that FR is the most prevalent. Poor pen conditions are risk factors for both FR and DD, but the epidemiology of the two diseases is quite different. Whereas FR is diagnosed throughout the feeding period, DD typically occurs after 80 days on feed (DOF). TTNS is the least prevalent of the three FRL, but has the greatest negative effect on animal welfare and production performance. Most TTNS cases occur within 50 DOF with treatment failure leading to a significant loss in production performance and even death. This review provides an overview of the epidemiology of lameness in feedlot cattle with emphasis on the prevalence and risk factors associated with FR, DD, and TTNS. [ABSTRACT FROM AUTHOR]

Increasing sow milk yield is essential to achieve maximal growth of suckling piglets, and nutrition can stimulate milking capacity. From 90 days of age until puberty, replacement gilts should not undergo major feed restriction as it will inhibit mammary development. Providing phytoestrogens in that period will stimulate mammary hyperplasia. During gestation, feed intake of gilts must ensure that backfat at the end of gestation is above 16 mm to support mammary development. In the last third of gestation, providing 40% more lysine than requirements via the addition of soybean meal increases mammary mass in gilts, but not in multiparous sows. A high nutrient intake during transition is crucial, whereby providing sows 12.6 Mcal metabolizable energy and 22.0 g standardized ileal digestible (SID) Lys daily ensures a high colostrum production and maximizes milk yield in the following lactation. During lactation, there are quadratic effects of energy and protein intakes on the weight of suckled mammary glands and sows should not be restricted-fed to avoid excessive mobilization of body reserves. Furthermore, the provision of adequate lysine is critical to maximize litter growth, with optimum daily intakes between 47.7 and 51.3 g SID Lys for primiparous sows and 51.3–67.2 g SID Lys for multiparous sows. [ABSTRACT FROM AUTHOR]

Plasma and tibia attributes were investigated in broiler chickens raised on three gut health management programs in commercial farms (study 1) and research station settings (study 2). The programs were as follows: (1) conventional antibiotics (CON), (2) raised without medically important antimicrobials (RWMIA), and (3) raised without antibiotics (RWA). Birds had free access to feed and water from placement to harvest; samples of blood and left tibia were collected on day 28 in both studies and further samples were taken on day 41 in study 2. In both studies, there were no program differences (P > 0.05) on plasma metabolites with exception of enzyme concentrations with notably higher levels of circulating plasma alkaline phosphatase (ALP) in birds reared on the RWA program (P ≤ 0.04). Differences were observed among programs for tibia length in both studies (P < 0.05). Birds reared on RWMIA exhibited significantly (P = 0.016) higher tibia ash than CON on day 41. Observed differences in the plasma enzyme concentrations, tibia length, and ash concentration suggest altered metabolism which could be linked to gut health management programs and their ability to support gut integrity and function in the absence of antibiotics. [ABSTRACT FROM AUTHOR]

We previously reported that high levels (≥50%) of black soldier fly larvae meal (BSFLM) reduced growth and altered organs morphology in broiler chickens. Herein we further examined gastrointestinal, breast, bone, plasma, and litter attributes in broiler chickens fed partial to complete replacement of soybean meal (SBM) with BSFLM. A total of 1152 day-old Ross × Ross 708 male chicks (n = 8) were allocated to 48 pens and assigned one of six diets: a basal corn-SBM diet (0BSFLM), four diets in which SBM in 0BSFLM was replaced with BSFLM at 12.5%, 25%, 50%, and 100% (12.5BSFLM, 25BSFLM, 50BSFLM, and 100BSFLM) and a final diet (0 + AGP) in which 0BSFLM was fed with coccidiostat and antibiotic. Birds were bled for plasma and necropsied for samples. Litter samples were collected on days 45 to 47. Breast weight, woody breast, and hardness scores and tibia morphometry reduced linearly in response to BSFLM inclusion (P < 0.001). BSFLM linearly increased plasma Lys, Met, Thr, uric acid, creatine kinase and decreased Arg and potassium (P < 0.05). Litter ammonium nitrogen and potassium decreased linearly in response to BSFLM (P < 0.001). In conclusion, the data suggested physiological and metabolic inefficiencies in broiler chickens fed isocaloric and isonitrogenous diets with ≥50% BSFLM replacement of SBM. [ABSTRACT FROM AUTHOR]

The current interest in hemp is not limited to the medicinal use for humans, it is also gaining attention as a valuable feed ingredient for animals. For instance, the processing of whole hemp seed (HS) for the extraction of the oil can result in various feed materials for animals, including HS hulls, dehulled HS, HS oil, and HS cake/meal. However, currently, HS-derived products are not approved as feed ingredients in Canada, in part, because the safety and efficacy of these derivatives, like other jurisdictions, require certification by regulatory bodies for their use in animal feeds. In this context, this document reviews previous studies testing the application of hemp-derived products in various animal feeds, including poultry, swine, ruminants, as well as in aquaculture production to support their safety and efficacy. Furthermore, the document attempts to review available data on the transfer of delta-9-tetrahydrocannabinol (THC; the psychoactive component) into animal products. Hence, the aim of this work is to support future policy directions and guidelines for the application of various hemp-derived products in animal feeds. [ABSTRACT FROM AUTHOR]

A total of 288 1-day-old Ross 308 broiler chicks were randomly allotted into four dietary treatments: (1) Control (CON; corn–wheat–soybean-based diet), (2) CON + 0.05% bacitracin methylene disalicylate (BMD), (3) CON + 0.3% red osier dogwood extract (ROD), and (4) CON + 2.5% grape pomace (GP) and raised for 28 days. On days 21–27, birds were exposed to either a thermoneutral (TN; 24 ± 1 °C) or heat stress (HS; 32–34 °C for 8 h/day) environment. On day 28, 12 male birds per treatment/temperature group were euthanized for measuring blood and intestinal health parameters. 0.05% BMD and 0.3% ROD inclusion improved (P ≤ 0.05) the average body weight gain and feed conversion ratio, compared to CON. HS reduced (P ≤ 0.05) average feed intake, bursa and spleen weights, plasma alanine transferase, lipase, and creatinine kinase but increased (P ≤ 0.05) alanine phosphatase and serum immunoglobulins compared to TN birds. HS further reduced (P ≤ 0.05) duodenal villus height (VH):crypt depth (CD), jejunal VH, and VH:CD but this was reversed by ROD and GP, and 0.05% BMD and 2.5% GP increased (P < 0.001) the relative abundance of Blautia and Sellimonas compared to the CON diet. ROD increased (P = 0.010) the relative abundance of Faecalibacterium compared to the BMD diet. The results suggest that 0.3% ROD extract may function as an alternative to antibiotics in improving broiler growth performance and intestinal health. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the ruminal degradation and intestinal digestion of nutrients of two cultivars of oat grains (CDC Nasser and CDC Seabiscuit) in comparison with a barley grain (CDC Meredith that was considered the control treatment) in dairy cows. Nasser showed higher rumen undegradable protein (RUP; P < 0.01) and intestinal digestible protein (P < 0.01) than Seabiscuit or control. However, the total digestible protein was not different among grain varieties (P = 0.25). The in vitro intestinal digestibility of RUP (dIBP) for Nasser was higher than control (P = 0.02); however, the dIBP in Seabiscuit did not differ from other cultivars. The intestinal digestible rumen bypass starch and total digestible starch were lower in the oat grain varieties than in the control (P < 0.01). The truly absorbed protein supplied to the small intestine (DVE) was highest for control, intermediate for Seabiscuit, and lowest for Nasser (P < 0.01). Moreover, control showed a higher estimated feed milk value than oat varieties (P < 0.01). In conclusion, Seabiscuit shared similar rumen degradation and intestinal digestibility with control suggesting that Seabiscuit oat grain could in some extension replace barley grain in diets for dairy cows. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The soybean industry in Canada is seeking opportunities to expand cultivation due to economic and environmental benefits of growing soybean. Climate projections indicate that soybean expansion into Saskatchewan would be possible with the increases in the available crop heat units under a future warmer climate; however, crop water availability could limit yields. Using a crop growth model, we simulated soybean yields within the Canadian Regional Agricultural Model regions in Saskatchewan for the near-term (2030s), mid-term (2050s), and distant future (2070s) periods under different climate scenarios. Soybean yields were simulated without water stress (potential yield), with water stress (rainfed yield), and under full and partial irrigation scenarios. Irrigation water needs were estimated under the irrigation scenarios and irrigation water availability was discussed. Our results suggest that reasonable and likely more profitable yields (∼2000–2500 kg ha−1) can be achieved under rainfed conditions in the Black soil zone neighbouring Manitoba but soybean production would be less favourable in the Dark Brown soil zone and least favourable in the Brown soil zone. Northeastern regions in the Black soil zone were found to be suitable for growing soybean cultivars in the maturity group (MG) 0 in the distant future and MG 00 in the mid-term under the medium–high greenhouse gas emission scenarios. Soybean would still not be suitable in the northwestern region. Our results indicate that regions in central Saskatchewan requiring 120–170 mm of irrigation are more likely to benefit from the proposed Lake Diefenbaker Irrigation Projects in the future. [ABSTRACT FROM AUTHOR]

Low-temperature flooding and ice encasement (LTFIE) cause variable survival of winter wheat (Triticum aestivum L.) in Ontario, which limits the adoption of wheat into crop rotations by growers. The development of novel cultivars capable of withstanding LTFIE is a promising avenue for improvement, but the methods used to assess the survival of winter wheat under LTFIE are restricted. This study developed updated methods to determine the survival of wheat cultivars under LTFIE using controlled environments and, to our knowledge, is the first method since the 1980s to use Canadian eastern soft red winter wheat (CESRW) to conduct cold tolerance studies. Chamber-acclimated plants of AC Carberry (spring wheat control), Branson (CESRW), CM614 (CESRW), and Norstar (hardy Canadian western red winter control) cultivars were used to estimate the days (LD50) and temperature (LT50) to reach 50% mortality under ice and without ice treatments. Norstar had the longest LD50 at 33 days, Branson and CM614 had similar LD50 of 18 and 20 days, and AC Carberry did not reach an LD50 as it died early in both treatments. The LT50 of each cultivar was different; Norstar had the lowest LT50 (−13.6 °C day 0 and −13.2 °C day 7), and AC Carberry had the highest LT50 (−6.6 °C day 0 and −2.7 °C day 7). The detailed methods developed in this study were more reliable compared to older methods based on the more accurate reported LD50 and LT50 of the cultivars, therefore, these methods can be used to screen winter cereals for LTFIE in the future. [ABSTRACT FROM AUTHOR]

Two experiments were conducted in a naturally lit research greenhouse to validate our modified strategy for delivering nutrients to sub-irrigated chrysanthemum plants. A split-plot design was used with four blocks arranged randomly, three nutrient rates as the main plot, and two contrasting cultivars as the subplot. The entire nutrient supply was removed at bud break and markedly reduced during vegetative growth, compared to common commercial fertilizer formulations, without adversely affecting tissue nutrient levels and plant/inflorescence quality, indicating that the plants were functioning in the low nutrient sufficiency zone. Specific nutrients (Nt) were more likely to exhibit improved uptake efficiency (shoot Nt content/Nt supply) than improved utilization efficiency (inflorescence DM/shoot Nt content) with decreasing nutrient supply. Thus, the common practice of delivering superfluous nutrient levels to greenhouse-grown chrysanthemum has little scientific merit in terms of nutrient accumulation and plant longevity. Applying a low‐input nutrient delivery strategy to the cultivation of indoor-grown, potted ornamental plants would improve the overall sustainability of the Canadian floricultural industry. [ABSTRACT FROM AUTHOR]

Differential thermal analysis (DTA) is a technique commonly used to evaluate the cold hardiness of plant organs that supercool as a means for cold survival. The aim of this study was to evaluate the effect of different pretest bud storage conditions, cooling rates, and bud excision techniques on dormant sweet cherry flower bud low temperature exotherms (LTEs) measured using DTA. Furthermore, this study compared cold hardiness estimates made using DTA and controlled freezing tests. We determined that buds stored at warmer temperatures (12.5 °C and room temperature) for 2–6 h prior to DTA or transported to the lab in a moist environment underwent biologically relevant changes in their apparent sensitivity to cold, as indicated by LTEs produced at warmer temperatures. The DTA cooling rate also significantly affected LTEs, with faster cooling resulting in the production of LTEs at warmer temperatures. Overall, LTEs were comparable among buds with varying amounts of plant material remaining attached to the bud base. It is important to note that the region directly subtending the primordia was always left intact on the buds being compared. This study demonstrated that overall, DTA and controlled freezing tests resulted in comparable measures of cold hardiness. The findings presented in this study are pertinent to researchers interested in conducting cold hardiness measurements in sweet cherry and highlight that consistency in DTA pretest conditions and bud preparation are required to achieve reliable LTE results that can be compared among studies. [ABSTRACT FROM AUTHOR]

Prairie cropping systems face several challenges, including high input costs and climate change. Research to address these challenges has focused on above-ground agronomic parameters while completely ignoring the role roots play below ground. The objectives of this review study are to (i) synthesize past root studies carried out in the Canadian Prairies, (ii) provide a context for prairie root research, and (iii) identify gaps for future research. This review reports that root architectural traits of major crops have been assessed under field and greenhouse conditions in soil, artificial media, and a mixture of both soil and media, mostly under natural/well-watered and drought conditions. Several root traits have been compared for major crops grown with respect to moisture levels and nutrient uptake. A dearth of research exists on the complex relationship between root traits, soil microbiome, nutrient uptake, carbon sequestration, and photosynthetic efficiency. No studies were found relating root traits, fertilizer placement, and nitrogen and water use efficiencies, carbon sequestration, soil microbiome dynamics, and common root diseases. This review also reports that more research and funding are needed to exploit the benefits that root research will bring to further sustainability goals and ensure food security in the Canadian Prairies. [ABSTRACT FROM AUTHOR]

Hybrids between Corylus avellana and Corylusamericana are one of several new perennial and winter annual crops being developed as part of the Forever Green Initiative at the University of Minnesota. As a woody perennial shrub, hazelnuts in agroforestry systems can provide a new revenue source for rural landowners; continuous living cover to prevent soil erosion, sequester soil carbon, protect water quality, and provide wildlife habitat; and a delicious and healthful new local food. If hazelnuts are to fulfill their potential, better germplasm and better nitrogen fertilization recommendations are both needed. We modeled these trials after trials by R.E. Worley, who showed that yields of pecan trees fertilized only when leaf nitrogen (N) fell below critical thresholds were maintained with lower levels of applied N, benefitting both the environment and growers' profits. Results of trials at three Minnesota sites, comparing N applied only when leaf N fell below 1.8%, 2.0%, or 2.2% with annual N applications and no N over 4 years, support using 2.2% leaf N as the critical threshold for N fertilization. Our results showed that whereas only 8% of N applied annually ended up in the harvested nuts and husks, N that was applied to plants that demonstrated hunger for it was more efficiently taken up. Our results suggest a need for more productive germplasm and further research to develop best management practices for N fertilization. [ABSTRACT FROM AUTHOR]

This document contains three separate articles related to dairy cattle research. The first article explores the use of depth imaging as a noninvasive method to measure daily dry matter intake (DMI) in dairy cattle. The researchers found that depth imaging showed promise as a constant measure of DMI on an individual cow basis, potentially providing a more accurate and efficient method for monitoring feed intake. The second article compares different nutrient requirement models and their effects on dairy cattle diets and methane emissions. The study found that using the NASEM (2021) model resulted in lower methane emissions compared to the NRC (2001) model. The third article focuses on optimizing diets for automatic milking systems using mixed-integer, nonlinear programming. The study developed optimized diets that reduced cost and predicted group performance. [Extracted from the article]

The objectives were to develop equations for predicting ileal digestible phosphorus (P) based on nonphytate P, phytate P, calcium to nonphytate P ratio, and exogenous phytase concentrations in broiler diets and to evaluate the accuracy of the models. The modified Michaelis–Menten model was used to predict apparent ileal digestible (AID) or standardized ileal digestible P in broiler diets. Two different methods were used to analyze 25 published ileal digestible P data to evaluate the accuracy of the equation for predicting AID P. The first method assessed mean and linear biases. While the mean bias was significant (P < 0.05), the linear bias was not significant. The second method involved regressing the 25 AID P data against those predicted by the current model. The results showed that the intercept and slope of the regression were not statistically different from 0 and 1, respectively. This suggests that the current equation accurately represents the test data. In conclusion, the accuracy of the model depends on validation processes. Considering that the current model was developed using various phytase products, it would be preferable to use an equation that is based on a single phytase product if requisite quantity of data is available. [ABSTRACT FROM AUTHOR]

In Canada, new forage varieties need not undergo grazing trials before registration and sale. To evaluate the effect of grazing, six cool-season species including meadow bromegrass (Bromus riparius Rehmann), orchardgrass (Dactylis glomerata L.), sainfoin (Onobrychis viciifoila Scop.), and three alfalfa varieties (Medicago sativa L.) were established in monocultures and grass–legume binary mixtures in Saskatchewan, Canada. Forage treatments were randomly established within each of three 3.5 ha paddock replicates. In Year 1, 69 Bos taurus crossbred steers, and in Year 2, 149 steers were homogenously allocated to the three paddocks for the grazing trials. Alfalfa monocultures had the greatest (p < 0.05) pre-graze forage yields and crude protein content. Leaf area index was greater in alfalfa monocultures than in all other treatments (p < 0.01). Etiolated growth differed (p < 0.05) among binary mixtures but not monocultures. Alfalfa monoculture stands were preferred over grass monocultures and most grass–legume mixtures, and sainfoin was avoided relative to alfalfa. Killarney orchardgrass was the least productive and least preferred among forages evaluated. In summary, alfalfa monocultures had greater (p < 0.05) forage yields and quality than sainfoin monocultures, grass–legume binary mixtures, or grass monocultures. [ABSTRACT FROM AUTHOR]

This study assessed the environmental impacts of beef cattle production and their effects on the overall sustainability of Canadian beef production. Cradle to farm gate, cradle to processor's gate, and cradle to consumer plate life cycle assessments were carried out to quantify greenhouse gases (GHG), resource use (i.e., water, land, and fuel), and potential water and air pollution (i.e., freshwater eutrophication, terrestrial acidification, and photochemical oxidants formation). Across the production chain, feed production had the greatest impact on most environmental indicators. The GHG intensity without dairy meat was estimated as 10.4 kg CO2-eq per kg of live weight (LW), corresponding to 32.8 kg CO2-eq per kg of consumed boneless beef. Including dairy meat reduced GHG intensity by 5.8% (0.6 kg CO2-eq kg LW–1) compared to when it was excluded. Other environmental metrics per kg of LW were 657 L, 38.7 m2 annual crop-eq, 0.4 kg oil-eq, 2.6 kg P-eq, 115.9 kg SO2-eq, and 8.7 kg NOx-eq for water use, land use, fossil fuel use, freshwater eutrophication, terrestrial acidification, and photochemical oxidants, respectively. Data provide benchmarks for use in future regional and national assessments that are designed to encourage the adoption of sustainable management practices that can lower the environmental footprint of Canadian beef production. [ABSTRACT FROM AUTHOR]

The objective of this study was to quantify the impact of Zn and Cu supplementation and nutritional factors on the digestible content of these minerals using a meta-analysis approach. A database derived from 24 publications and describing 142 experimental treatments was compiled. A model showed that positive effects of chelated, (linear and quadratic, P < 0.01) and inorganic Zn supplementation (P < 0.05) (linear and quadratic, P < 0.01), Zn from ingredients (linear, P < 0.01) and a negative linear effect of dietary Cu concentration (P = 0.067; R2= 94%) on digestible Zn content. In other model, addition of phytase showed linear improvement of digestible Zn (P < 0.01; R2= 96%). For digestible Cu, a model showed that chelated and inorganic Cu supplementation (P < 0.01) linearly increased digestible Cu while dietary Zn level decreased it (P < 0.01; R2 = 93%). Dietary phytase did not impact digestible content of Cu. The digestibility of Zn and Cu depends on dietary supplementation of these minerals in diets but also on the interaction between these minerals. Finally, phytase supplementation improves digestible Zn content but not Cu. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Crop rotations in the northern Great Plains of North America increasingly include corn (Zea mays L.) and soybean (Glycine max (L.) Merr.). Use of cover crops, while less extensive, is also increasing given their purported agronomic and environmental benefits. To date, soil responses to the inclusion of corn, soybean, and cover crops in rainfed cropping systems have not been well documented in the region. Therefore, soil properties were evaluated 6 years after establishment of three crop rotations (spring wheat (Triticum aestivum L.)–soybean (SW–S), spring wheat–corn–soybean (SW–C–S), and spring wheat–corn–cover crop (SW–C–cc)) each split by no and minimum tillage on a Dark Brown Chernozem near Mandan, ND, USA. Soil responses to treatments were subtle and exclusive to the 0–7.6 cm depth. Soil pH was lower in SW–S than SW–C–cc (5.28 vs. 5.48; P = 0.05), SO4-S was greater under SW–C–cc than SW–C–S (13.4 vs. 11.6 g S kg−1; P = 0.03), exchangeable K was greater under SW–C–S and SW–C–cc than SW–S (0.83 cmol kg−1 vs. 0.52 cmol kg−1; P = 0.05), and water-stable aggregates were greater in SW–S than SW–C–S (26% vs. 19%; P = 0.08). Soil organic carbon (SOC) and total N did not differ among crop rotations or between tillage treatments, while particulate organic matter N was greater under no tillage compared to minimum tillage (P = 0.08). Between 2012 and 2018, soil pH decreased and SOC increased under SW–C–S. Frequent monitoring of near-surface soil conditions in rotations with soybean every other year is recommended. Furthermore, innovative management practices are needed to enhance soil C and N fractions in rotations with full-season cover crops. [ABSTRACT FROM AUTHOR]

Minimizing tillage has been promoted as an agricultural practice that may mitigate greenhouse gas emissions through carbon sequestration. However, there is some ambiguity regarding the effect of minimum tillage (MT) on emissions of other greenhouse gases, in particular soil nitrous oxide (N2O) emissions. To determine how effective MT could be in helping Canada mitigate greenhouse gas emissions, we used a meta-analysis to compare growing season N2O emissions from MT versus conventional tillage (CT). Overall, MT had 12% lower N2O emissions compared to CT (P = 0.03). However, there was high variability due to soil texture and growing season precipitation (GSP), with MT tending to emit more N2O than CT in climates where GSP exceeded 600 mm, particularly for soils with sand content less than 60%. Therefore, unless long-term tillage trials, which are urgently needed in eastern Canada, show a reduction in N2O emissions over time, MT should be used as a greenhouse gas mitigation measure only in dry climates or on sandy soils. [ABSTRACT FROM AUTHOR]

Crop yields directly affect carbon (C) inputs into soils. Tillage management can influence crop performance, and as such should be considered when quantifying soil organic carbon (SOC) change, and thus net greenhouse gas emissions from croplands for national greenhouse gas inventory reporting. We conducted a meta-analysis of the effects of no-tillage (NT) and conventional tillage (CT) on crop yields for multiple crop species, soil types, and climatic regions of Canada. Yield response to NT varied between western and eastern Canada. Regardless of crop type, experiment duration, soil texture, and residue management, experiments in eastern Canada showed an average of 6% lower yields (p ≤ 0.005) under NT compared to CT. In western Canada, crop type had an important effect on yields between NT and CT with wheat, canola, and legumes exhibiting 10% (p ≤ 0.001), 7% (p ≤ 0.05), and 9% (p ≤ 0.05) higher yields on average under NT compared to CT, respectively. In western Canada, higher yields would be reflected in a similar scale of higher C inputs to NT systems. A recent meta-analysis of the effects of tillage management on SOC in Canada showed an 8% higher storage of SOC under NT systems compared to CT, a difference limited to western Canadian soils. Incorporating the effect of tillage on C inputs will lead to improvements in the accuracy of the effects of tillage management on SOC change in Canadian cropland. The activity data can be improved by applying weightings to the yield data by site-specific assessment of tillage practices across Canada. [ABSTRACT FROM AUTHOR]

The impact of different fertilizer types with equal nitrogen levels on maize root morphology and soil available nutrient is needed, especially in coal mine reclamation areas. After 9-year fertilization, the maize root biomass, length, and surface area of the organic–inorganic fertilization (OF) treatment were significantly higher than those of other treatments. The contents of available phosphorus and available potassium were 18.46 and 176 mg·kg−1, respectively, under OF treatment, which were significantly higher than those under other treatments. Our findings indicate that the fertilizing effect of OF treatment is effective for soil reclamation in mining areas. [ABSTRACT FROM AUTHOR]

This study reviewed the literature on soil conservation practices and analyzed four case studies in different soil zones and diverse cropping systems of Manitoba (MB), western Canada, to show the potential impacts of no-till/reduced tillage practices on field crop economic performance. Primary and secondary data, such as tillage type, input cost, crop price, crop yield, and net revenue (NR), were used to assess the tillage practices in each of the case studies. Based on crop economic analysis, over 9 years (1998–2006) in southern Manitoba, cereal-based (spring wheat (Triticum aestivum L.) and barley (Hordeum vulgareL.)) cropping systems were more profitable under conservation tillage than conventional tillage practices, whereas the opposite was true for oilseed crops (e.g., canola, Brassica napus L.). In plot-scale studies at Portage, MB, low intensity tillage increased NR for soybean (Glycine max L.) in 1 of 3 years when compared to high intensity tillage, and there appeared to be lower NRs for canola as tillage intensity increased. However, in studies near Brandon, MB, NRs for a 4-year wheat-pea (Pisum sativum L.) rotation were lower in low disturbance seeding than high disturbance seeding systems for a clay loam soil but similar for a loam soil. While no single tillage system was found to consistently provide the highest NR based on these case studies, these findings provide insights into some of the factors behind decisions surrounding tillage management and the rationale for the continued use of a combination of conventional, reduced, and zero-till systems in the eastern Prairies of Canada. [ABSTRACT FROM AUTHOR]

Shellfish culture heavy soils are suitable for the cultivation of marine organisms and are essential for the development of marine fisheries. To study both the interaction between heavy soil particles and that between the soil and soil-engaging components of agricultural machinery in shellfish culture, the simulation parameters in the model were determined. To study the interaction between soil particles in the viscous soil of shellfish culture with moisture content of 26.51% ± 1%. Discrete element method is used to establish the accumulation simulation experiment; the contact parameters between soil particles were calibrated. The response surface optimization technique was used to create the accumulation angle regression model. To study the interaction between the soil and soil-engaging components, the static friction coefficient between the heavy soil and soil-engaging components was determined by static friction experiment. The contact parameters between the soil and soil-engaging components were calibrated by the slope simulation experiment; the rolling distance regression model was established by response surface optimization methodology. The findings demonstrate that the optimized soil model can simulate the actual soil, and reflect the interaction between the heavy soil particles, soil, and the soil-engaging components of agricultural machinery, which not only provides a theoretical basis for the design and optimization of soil-engaging components of agricultural machinery in heavy soil, but also provides a new way for the research and development of agricultural machinery in a complex environment. [ABSTRACT FROM AUTHOR]

This study aims to compare decision tree (DT) and artificial neural network (ANN) models, in addition, the efficiency of geomorphic surface attributes in predicting soil texture classes. The study area is located in the north of Chaharmahal and Bakhtiari province, central west Iran, and covers 6875 ha. Ninety-six pedons were excavated on separated geoforms. Soil samples of top soil (A horizon) were analyzed for clay, sand, and silt contents. Totally 57 auxiliary variables, including the derivatives of digital elevation model (DEM), Landsat 8 images, geomorphic surface map, geology map, and land-use map, were used to predict both soil texture classes and soil particle size fractions. Root-mean-square error (RMSE), R² or the coefficient of determination (R_square), overall accuracy, and Kappa coefficient were selected as criteria for evaluating model performance. The R-square coefficients of clay, silt, and sand fractions for both models, respectively, were 0.41, 0.25, and 0.63 for ANN and 0.52, 0.62, and 0.75 for DT. According to RMSE, R-square, overall accuracy, and Kapa coefficient of validation data, the DT model produced better prediction fits to the both soil particle-size fraction and soil texture classes and was the most accurate classifier model. The parameters were 0.59, 0.09, 0.66, and 0.24 for ANN and 0.41, 0.75, 0.76, and 0.60 for DT models, respectively. The accuracy of each individual soil texture class was generally dependent upon the number of soil texture observations in each texture class. According to this fact, both models had better prediction for silty clay loam and clay loam texture classes. [ABSTRACT FROM AUTHOR]

Silymarin is the flavonoid extracted from Silybum marianum seed. It has anti-inflammatory and antibacterial properties, and it supports liver health. The growth performance parameters, nutrient digestibility, and blood profile in growing pigs fed the dietary Silybum marianum seed extract were analyzed in this study. A total of 196 crossbred growing pigs ((Yorkshire × Landrace) × Duroc) were allocated into three dietary groups: CON: basal diet; TRT1: basal diet with 0.05% Silybum marianum seed extract; and TRT2: basal diet with 0.10% Silybum marianum seed extract. Results showed that pigs fed with Silybum marianum seed extract up to 0.10% increased average daily gain (p < 0.10) and feed intake (p < 0.05). The digestibility of dry matter, nitrogen, and energy were increased linearly (p < 0.05) with addition of Silybum marianum seed extract up to 0.10%. However, serum bile acids, alanine aminotransferase (ALT), and aspertate aminotransferase (AST) were not changed (p < 0.05). In conclusion, the significant improvements in average daily gain, feed intake, and nutrient digestibility indicate that Silybum marianum seed extract can positively influence the growth of growing pigs. Finally, natural feed additives like Silybum marianum seed extract may be used as an efficacious growth promoter and ultimately contributing to sustainable pig farming. [ABSTRACT FROM AUTHOR]

This study examined the effects of mixed-species direct-fed microbial (DFM) on growth performance, gas emissions, meat quality, nutrient digestibility, and the fecal score of finishing pigs. A total of 100 crossbred finishing pigs ((Yorkshire × Landrace) × Duroc) weighing 58.97 ± 3.12 kg were randomly assigned to one of two diets (5 pigs per pen (2 barrows and 3 gilts); 50 pigs per treatment) in an 8-week trial. Dietary treatments comprised of the basal diet without probiotics control or basal diet + (0.1%) mixed probiotics (DFM). Mixed DFM supplementation showed a tendency to increase (P = 0.093) the body weight of finishing pigs during day 56. Comparing mixed DFM with the control diet, mixed probiotics significantly improved average daily gain (ADG) during weeks 5–8 (P = 0.024) and overall (P = 0.013). DFM-supplemented diets reduced the emission of CH4 and NH3 significantly at weeks 4 and 8 compared with control. DFM supplementation did not affect H2S, methyl mercaptans, acetic acid, or CO2 emissions. Mixed DFM supplementation showed a tendency to increase (P = 0.07) nitrogen digestibility. Pigs receiving mixed DFM had improved ADG and reduced NH3 and CH4 emissions without affecting meat quality, nutrient digestibility, intestinal microbes, and fecal score. [ABSTRACT FROM AUTHOR]

Image analysis of ventral, anterior, and posterior ends of 550 pork loins was used to classify extreme-coloured centre chops. Only the ventral side was strongly correlated (r = 0.79) to the centre chop. Thresholds at 2.5th, 5th, and 7.5th percentiles of ventral surface pale pork were selected to classify centre chop pale pork (5th percentile). Increasing stringency increased accuracy in excluding pale samples. At the 7.5th percentile, prediction accuracy of pale (85.7%) and non-pale samples (89.5%) was balanced. This method can be adopted by commercial pork processors as a classification or pre-sorting approach. [ABSTRACT FROM AUTHOR]

Light impacts layer hen's welfare and production. This study investigated the effects of a novel LED light system on blood physiological variables in laying hens. In each of the two trials, 320-layer pullets were allocated to 16 groups of 20 birds. Treatments included the prototype LED lighting (two rooms) and the conventional 2700 K LED bulbs (two rooms). On each sampling day, blood samples were collected and analyzed immediately. Results show that only a few physiological variables were affected by treatments, but age had effects on most examined variables. No effects of treatments or age on plasma corticosterone signify a similar level of physiological stress. [ABSTRACT FROM AUTHOR]

In this study, 206 breast fillets were purchased from grocery stores in the province of Quebec and evaluated for the presence of different quality defects. Of these fillets, 48.5% showed breast muscle myopathies (BMM), 19.4% showed pale, soft, and exudative (PSE), and 6.8% showed dark, firm, and dry (DFD) attributes. BMM were equally present (P > 0.05) in fillets of economical, commercial, and high-quality brands, while PSE-like fillets were more present in economical brands (P < 0.0001). The combined effect of BMM and DFD induced significantly higher counts of Salmonella (P = 0.03) and Enterobacteriaceae (P = 0.03) in myopathic than in unaffected fillets. These quality defects also altered the nutritional quality of breast meat: BMM-affected fillets had greater fat content (P < 0.0001) and DFD fillets had lower protein content (P = 0.041) than normal fillets. The technological quality was only slightly impacted by BMM, while PSE-like fillets had higher cooking loss (P = 0.009) and a tougher texture after cooking (P < 0.0001) than DFD fillets. For the first time, this study confirmed the presence of multiple quality issues in the Quebec poultry supply chain, and provided valuable data to support future research efforts. [ABSTRACT FROM AUTHOR]

Methylsulfonylmethane (MSM) is a natural organic sulfur component that has anti-inflammatory and antioxidant properties. In this study, injury of porcine intestinal epithelial cell (IPEC-J2) models were used to investigate the effect of MSM on lipopolysaccharide (LPS)-induced porcine intestinal epithelium barrier damage. The results of the cell cycle showed that the cells in the G2/M phase decreased significantly with the supplementation of 300 mmol/L MSM (P < 0.05). The ELISA assay revealed that MSM could significantly inhibit the expression of tumor necrosis factor-alpha, interleukin-1, and interleukin-6 (P < 0.01). Meanwhile, MSM could significantly increase the value of cell monolayer transepithelial electrical resistance while reducing the FITC-dextran flux permeability and lactate dehydrogenase activity in IPEC-J2 cells (P < 0.01). Additionally, 300 mmol/L MSM significantly increased both mRNA and protein expression of occludin, claudin-1, and ZO-1 (P < 0.05). Furthermore, MSM prevented the downregulation of epidermal growth factor receptor (EGFR) by LPS, indicating that MSM might enhance tight junction function through mechanisms of activation of EGFR-mediated protein synthesis in IPEC-J2 cells. Therefore, our findings suggested that MSM has protective effects on inflammation and epithelial barrier injury in LPS-induced IPEC-J2 cells, indicating that MSM might be used as a potential therapeutic agent in the pig industry. [ABSTRACT FROM AUTHOR]

This experiment evaluated the effects of sugarcane extract (SCE) on growing pigs' diarrhea incidence, serum immunity, intestinal morphology, and antioxidant enzyme activity. A total of 116 52-day-old commercial pigs (Duroc × Landrace × Jiaxing Black, average weight of 11 ± 1 kg) were randomly allocated to control (CON, basal diet) and 1% SCE group (SCEG, basal diet + 1% SCE). The experiment lasted four weeks. Compared with CON, diarrhea incidence (SCEG: 74.11% versus CON: 54.76%) and diarrhea index (SCEG: 83.65% versus CON: 73.61%) dropped largely in pigs supplemented with SCE. Villus height in the duodenum (p < 0.01) and the ratio of villus height to crypt depth (p < 0.05) increased in SCEG. Dietary SCE enhanced the activity of catalase (CAT) capacity, and decreased tumor necrosis factor α, and malondialdehyde levels in serum (p < 0.05). CAT activity in the ileum increased (p < 0.05) in piglets supplemented with SCE. Thus, dietary supplementation with SCE improved diarrhea incidence, serum antioxidant capacity and immunity, and intestinal villus morphology and may be used as an efficient antibiotic alternative in weaned piglet feed. [ABSTRACT FROM AUTHOR]

Greenhouse gas (GHG) and ammonia (NH3) emissions, land and water use associated with feedlot cattle (n = 40 hd treatment−1 trial−1) treated with or without productivity-enhancing technologies were modelled for a multiyear study (n = 4). Heifers (H) were assigned to the following treatments: (1) implanted (HTBA); (2) provided with melengestrol acetate (HMGA); (3) nonimplanted control, weight-adjusted (CON_Adj) to achieve the same final carcass weight (CW) as 1 (HCON_AdjTBA); or (4) CON_Adj to achieve the CW as 2 (HCON_AdjMGA). Steers (S) were assigned as follows: (1) implanted (STBA); (2) implanted and provided with ractopamine hydrochloride (SRAC; conducted in the last 2 years); (3) CON_Adj to achieve the same CW as 1 (SCON_AdjTBA); or (4) CON_Adj to achieve the same CW as 2 (SCON_AdjRAC). The GHG and NH3 emissions from HTBA, HMGA, STBA, and SRAC were 3.8%, 3.0%, 10.1%, and 8.5% lower and 4.3%, 2.9%, 7.4%, and 7.6% lower, respectively, than the respective control cattle. The land required to produce feed was also reduced by 6.6%, 4.8%, 9.9%, and 10.9%, while water use was reduced by 6.4%, 4.8%, 10.1%, and 11.1% for HTBA, HMGA, STBA, and SRAC, respectively. This modelling study clearly demonstrates that conventional beef production systems have a lower environmental footprint than nonconventional systems. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effects of substituting barley grain with short-season, high-moisture shelled corn, and barley grain and barley silage with snaplage on ruminal fermentation and the site and extent of digestion in beef cattle fed finishing diets. Six ruminally and duodenally cannulated heifers (420 ± 16.4 kg body weight) were fed a barley grain and silage finishing diet (BG), a diet where half of the barley grain was replaced with high-moisture shelled corn (HC), or a diet where the barley silage and a portion of grain were replaced with snaplage (SN) in a replicated 3 × 3 Latin square design. While dry matter and starch intake were unaffected, feeding SN resulted in greater (P = 0.02) ruminal but not total tract starch digestibility than BG. Ruminal pH did not differ between HC and BG, but SN reduced (P = 0.02) minimum ruminal pH relative to BG. Feeding BG increased (P = 0.04) ruminal ammonia concentrations over HC. In conclusion, high-moisture shelled corn can partially replace barley grain with minimal impact on nutrient digestibility or ruminal fermentation, but replacement of barley silage and some barley grain with snaplage may increase the risk of ruminal acidosis. [ABSTRACT FROM AUTHOR]

This study quantified the distribution of animals by farm size for portions of the dairy, beef, swine, and poultry sectors using the 2016 Census of Agriculture. Results showed that the distribution of farm sizes and animal populations were skewed or bimodal and varied by livestock type and by province. Thus, the average farm size has little meaning. Recognizing farm size diversity is important for developing effective policies and programs, conducting appropriate research, and developing practices and technologies to support farms of all sizes. [ABSTRACT FROM AUTHOR]

In a previous study (Assessment 1), an on-farm assessment tool was used to establish a standard across 60 Quebec dairy farms using animal-, stall-, and management-based measures of cow comfort. The objective of the present follow-up study (Assessment 2) was to perform a reassessment using an identical cow comfort assessment tool on a subset of the original farms expected to benefit most from applying the recommended changes, and to determine the effects of the modifications on cow comfort. From the subsample of farms, 24 reported applying stall modifications based on recommendations from Assessment 1 with the aim of promoting cow comfort (Adopters), while the remaining 10 farms did not (Non-adopters). The assessment tool included 19 target areas, grouped into 9 critical areas based on measures of cow comfort that considered housing, feed-water, health, and welfare. The on-farm report of Assessment 1 was found to increase producer awareness of issues in cow comfort measures on farms, as shown by an improvement in stall design according to recommendations based on cow body dimensions and reduced injury prevalence. Routine reassessment of cow comfort measures may be important to use in supporting target achievement improvements as part of welfare improvement strategies. [ABSTRACT FROM AUTHOR]