Applied Animal Science最新文献

{"title":"Invited Review: Role for isoacids in dairy nutrition*","authors":"J.L. Firkins ,&nbsp;K.E. Mitchell ,&nbsp;A.F. White","doi":"10.15232/aas.2024-02537","DOIUrl":"10.15232/aas.2024-02537","url":null,"abstract":"<div><h3>Purpose</h3><p>This literature review explains current understanding of the mechanisms by which branched-chain volatile fatty acids (BCVFA), historically termed isoacids, can improve fiber digestibility, microbial protein production, and either milk production or production efficiency.</p></div><div><h3>Sources</h3><p>Peer-reviewed literature and ADSA abstracts were the primary course of information reviewed.</p></div><div><h3>Synthesis</h3><p>Although traditionally included in isoacid supplements with the 3 BCVFA, the straight-chain valerate does not warrant being included. Because of the high concentration of its precursor leucine in corn protein, isovalerate is less likely to be needed than 2-methylbutyrate and isobutyrate. If conditions are not amenable for BCVFA assimilation into microbes, particularly if ruminal ammonia is deficient, more supplemental BCVFA are available for postruminal metabolism. Isovalerate is likely metabolized primarily in the rumen epithelium, whereas isobutyrate and 2-methylbutyrate are likely metabolized in the liver or peripheral tissues. If BCVFA improve fiber degradability, typically by 3 to 5 percentage units, a more balanced consortium of ruminal microbes should improve efficiency of microbial protein production so long as ruminal nitrogenous precursors are adequate.</p></div><div><h3>Conclusions and Applications</h3><p>Increased acetate production from improved fiber digestibility is thought to increase milk fat production, particularly in multiparous cows. In primiparous cows, the acetate from improved fiber degradability might be diverted to body weight gain. Milk production efficiency responses of 5% to 10% have been recorded with optimum doses of BCVFA and adequate rumen-degraded protein supply.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 4","pages":"Pages 466-477"},"PeriodicalIF":1.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000752/pdf?md5=04cc6ef2561f0eeb9eab855243253cff&pid=1-s2.0-S2590286524000752-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141952100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of feeding lubabegron fumarate or ractopamine hydrochloride to beef × dairy crossbred steers raised under small-pen commercial feedlot conditions in western Canada","authors":"A.L. Shreck ,&nbsp;C.A. McMullen ,&nbsp;M.L. May ,&nbsp;M.J. Quinn ,&nbsp;G.K. Jim ,&nbsp;B. Kromm ,&nbsp;J. Song ,&nbsp;O.C. Schunicht ,&nbsp;J.K. Merrill ,&nbsp;C.W. Booker","doi":"10.15232/aas.2023-02440","DOIUrl":"10.15232/aas.2023-02440","url":null,"abstract":"<div><h3>Objective</h3><p>This study evaluated the effects of feeding lubabegron fumarate compared with ractopamine hydrochloride in beef × dairy crossbred steers fed a corn-based diet in western Canada.</p></div><div><h3>Materials and Methods</h3><p>Beef × dairy (Limousin × Jersey) crossbred steers (n = 760, initial BW = 530.0 ± 34.7 kg) were randomly allocated 80 d before slaughter to 1 of 2 experimental groups. A total of 20 replicates were allocated to the study, with each replicate comprising 1 pen from each experimental group (for a total of 40 pens) and 19 steers per pen. Pen was the experimental unit. Experimental groups consisted of either lubabegron fumarate (Experior 10, Elanco Canada Limited, Mississauga, Canada) fed at a target level of 3.5 mg/kg diet DM for 56 d before slaughter (EXP) or ractopamine hydrochloride (Optaflexx 100, Elanco Canada Limited) fed at a target level of 250 mg/steer daily the last 28 d before slaughter (RAC).</p></div><div><h3>Results and Discussion</h3><p>Steers in the EXP group had lower DMI, greater carcass weight, and greater DP compared with steers in the RAC group. Steers in the EXP group had greater ADG and G:F on both a carcass weight and live weight basis compared with steers in the RAC group. Steers in the EXP group also had a greater proportion of YG Canada 1 carcasses, a lower proportion of QG Canada Prime carcasses, increased LM area, and a lower overall marbling score compared with steers in the RAC group.</p></div><div><h3>Implications and Applications</h3><p>Feeding lubabegron fumarate increased feedlot performance, the proportion of YG Canada 1 carcasses, and LM area, but decreased the proportion of QG Canada Prime carcasses and overall marbling score compared with feeding ractopamine hydrochloride. Magnitude of improvement in G:F was greater on a carcass weight basis than on a live weight basis.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 4","pages":"Pages 560-569"},"PeriodicalIF":1.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000843/pdf?md5=5294be8050b60113f0aecf34bfbb0580&pid=1-s2.0-S2590286524000843-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141962224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance of heifers grazing native or introduced mixed warm-season grasses during summer months in south-central United States","authors":"M.S. Gadberry ,&nbsp;N. Moss ,&nbsp;C.A. Tucker ,&nbsp;E.M. Wray","doi":"10.15232/aas.2024-02544","DOIUrl":"10.15232/aas.2024-02544","url":null,"abstract":"<div><h3>Objective</h3><p>This study compared weight gain and fecal egg count of heifers grazing native or introduced warm- season mixed-grass pasture.</p></div><div><h3>Materials and Methods</h3><p>Sixty fall-born, spring- weaned Angus crossbred heifers (8.5 mo old; 242 ± 26.9 kg) in each of 2 yr (2022 and 2023) were randomized to one of six 2.02-ha pastures (5 heifers/ha and 3 replicates per pasture type) of either native grass (NAT; predominately big bluestem [<em>Andropogon gerardi</em> Vitman]) or introduced mixed grass (WSMG; bermudagrass [<em>Cynodon dactylon</em> (L.) Pers.], crabgrass [<em>Digitaria</em> spp.], and foxtail [<em>Setaria</em> spp.]). Heifers grazed 84 d beginning the last week of May and were weighed every 28 d. Fecal samples were collected from each heifer toward the beginning and end of grazing for strongyle egg enumeration. Forage mass and nutritive value were assessed each time the cattle were weighed.</p></div><div><h3>Results and Discussion</h3><p>Forage mass and nutritive values differed for each year and pasture type. The NAT pastures had greater forage mass, lesser CP, and greater detergent fiber levels than WSMG. Season-long ADG differed by pasture type and year, with ADG being 0.22 kg/d greater in 2022 and 0.11 kg/d greater in 2023 for NAT. A forage system by sample day interaction in 2023 but not 2022 occurred with fecal egg counts.</p></div><div><h3>Implications and Applications</h3><p>At a fixed stocking rate, heifers continuously grazing native grasses dominated by big bluestem out gained heifers grazing mixed introduced warm-season grasses heavily infested with foxtails.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 4","pages":"Pages 456-465"},"PeriodicalIF":1.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000740/pdf?md5=3fd8f44832b005f521850968d797483f&pid=1-s2.0-S2590286524000740-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141952099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of virginiamycin to improve health of growing and finishing steers: II. Animal growth and development, and intake dynamics","authors":"Luiz F. Dias Batista,&nbsp;Madeline E. Rivera,&nbsp;Luis O. Tedeschi","doi":"10.15232/aas.2023-02510","DOIUrl":"10.15232/aas.2023-02510","url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to determine the inter- relationship between rumen health dynamics and animal growth and development characteristics of growing and finishing steers receiving virginiamycin (VM). A companion article was published previously (Rivera et al., 2024).</p></div><div><h3>Materials and Methods</h3><p>A total of 120 Angus-crossbred steers (304 ± 27 kg) were assigned randomly to 1 of 20 pens equipped with a Calan gate feed system from which animals within a pen received VM (240 mg/d) or not as follows: no VM (T₀₀₀); VM in the last 50 d (T₀₀₁); VM for the last 100 d (T₀₁₁); VM in the first 50 d (T₁₀₀); VM in the first 100 d (T₁₁₀); and VM for 150 d (T₁₁₁). At slaughter, the 9th to 11th rib section was collected from the right side of each animal’s carcass to estimate carcass and empty body composition. Data were analyzed using a random coefficients model with the pen as a random effect and animals within treatment as the subject.</p></div><div><h3>Results and Discussion</h3><p>Dry matter intake was less for T₁₁₁ compared with T₀₀₀; however, ADG was not different. Thus, VM improved G:F. The T₀₁₁ had greater DMI compared with T₁₁₀, which resulted in greater ADG with no difference in G:F. Apparent total-tract NDF digestibility was greater for T₁₁₁ than T₀₀₀, which was confirmed by an improved diet growth-adjusted ME for T₁₁₁ than T₀₀₀. The T₀₁₁ tended to have a greater carcass and final shrunk BW than T₁₁₀. Ether extract content of the 9th to 11th rib section tended to be decreased for animals that consumed VM regardless of the period or length of feeding, resulting in a tendency to have less empty body fat content.</p></div><div><h3>Implications and Applications</h3><p>In this experiment daily inclusion of VM during the overall feeding phase increased feed energy utilization, and its withdrawal during the end of the finishing phase (T₁₁₀) decreased DMI and ADG. Continuous VM feeding enhanced fiber digestion and energy utilization, likely due to it promoting ruminal health.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 4","pages":"Pages 487-503"},"PeriodicalIF":1.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000776/pdf?md5=14339720c9fbf804ec97a082db8ffe84&pid=1-s2.0-S2590286524000776-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141952105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Apparent metabolizable energy and performance of Northern Bobwhite quail fed selected grain sorghum varieties","authors":"A.H. Moritz ,&nbsp;S. Sasia ,&nbsp;J. Presgraves ,&nbsp;M.E. Blair ,&nbsp;R.E. Buresh ,&nbsp;W.C. Bridges ,&nbsp;M. Arguelles-Ramos ,&nbsp;T.A. Wilmoth","doi":"10.15232/aas.2024-02558","DOIUrl":"10.15232/aas.2024-02558","url":null,"abstract":"<div><h3>Objective</h3><p>One objective of this study was to determine the nitrogen-corrected apparent metabolizable energy (AME_n) content of tannin-free red/bronze, white/tan, and US No. 2 varieties of grain sorghum fed to Northern Bobwhite quail; the determinations were done when the quail were 6 and 11 wk of age. Our other objective was to evaluate the effects of AME_n on growth performance.</p></div><div><h3>Materials and Methods</h3><p>The AME_n content of red/ bronze, white/tan, and US No. 2 grain sorghum varieties was determined using a dextrose control diet as the standard, fed to 200 mixed-sex Northern Bobwhite quail. Weekly measures of mean BW and feed consumption were used to calculate BW gain, feed intake (FI), and feed conversion ratio (FCR). Analyses were based on a 2 × 4 factorial treatment design with age (grower and finisher phases) and grain types (corn-dextrose, red/bronze, white/tan, and US No. 2) defining the treatments. Cage was the experimental unit, with data analyzed using JMP Pro version 16 (SAS Institute Inc., Cary, NC).</p></div><div><h3>Results and Discussion</h3><p>The interaction between the diet and age effect was not significant for any of the variables assessed. Mean AME_n values of modern grain sorghum varieties for Northern Bobwhite quail at 6 wk of age were determined as 3,683 (red/bronze), 3,604 (white/ tan), and 3,625 (US No. 2) kcal/kg. At 11 wk of age, the determined AME_n values were 3,502 (red/bronze), 3,486 (white/tan), and 3,522 (US No. 2) kcal/kg. Age had a significant effect across AME_n, BW gain, FI, and FCR. Surprisingly, AME_n decreased with age, and sorghum varieties showed a greater FI versus the control diet. White/tan and US No. 2 sorghum reported a greater FCR than the control. The reduction in AME_n with age might reflect a complex interplay of physiological, dietary, and environmental factors in Northern Bobwhite quail, where further research for optimizing nutrition and management practices is warranted.</p></div><div><h3>Implications and Applications</h3><p>The findings revealed a comparable AME_n level among sorghum types and corn. This study aligns with the shared goals of wildlife conservation and agricultural sustainability, confirming tannin-free sorghum as a potential energy source to enhance the Northern Bobwhite quail habitat and breeding.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 4","pages":"Pages 535-541"},"PeriodicalIF":1.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000818/pdf?md5=ace77dab5da09075fd0c0d83dd26fb0e&pid=1-s2.0-S2590286524000818-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141962212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perspective and Commentary: Use of soy-based feedstuffs in low-alfalfa, high–corn silage diets for dairy cows","authors":"W.P. Weiss","doi":"10.15232/aas.2024-02563","DOIUrl":"10.15232/aas.2024-02563","url":null,"abstract":"<div><h3>Purpose</h3><p>Alfalfa inclusion rates in dairy cow diets are decreasing, often with a concomitant increase in corn silage. This article discusses how soy-based ingredients fit into diets containing lower levels of alfalfa and higher levels of corn silage.</p></div><div><h3>Sources</h3><p>The data and conclusions in this review are derived from peer-reviewed journal articles.</p></div><div><h3>Synthesis</h3><p>In many areas, corn silage is becoming the primary forage in dairy diets by replacing alfalfa. Replacing alfalfa with corn silage increases the need for supplemental protein. Soy ingredients are efficient sources of MP. The RDP fraction in soy is almost exclusively amino nitrogen, which is efficiently used by microbes, and the RUP is highly digestible. As the concentration of alfalfa decreases and the concentration of soy protein increases, less CP should be needed to meet the MP requirements. As corn silage replaces alfalfa, negative responses to greater starch concentrations increase. Soyhulls are highly digestible and contain little starch, which makes them a good replacement for starch in diets high in corn silage and low in alfalfa. Diets with little or no alfalfa that include soy products can produce similar amounts of milk and milk components using less starch and CP than diets with greater amounts of alfalfa.</p></div><div><h3>Conclusions and Applications</h3><p>As corn silage replaces alfalfa in diets, more supplemental protein will be needed, but often diet CP concentrations can be reduced when much of the supplemental protein derives from soy. Dietary starch concentrations should be reduced with low- alfalfa diets because of increased risk of acidosis. Replacing some of the starch with soyhulls reduces acidosis risk.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 4","pages":"Pages 478-486"},"PeriodicalIF":1.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000764/pdf?md5=39e30d35916002ac04b3958953a5d0eb&pid=1-s2.0-S2590286524000764-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141952101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Injecting Fusobacterium necrophorum into the peripheral circulation or hepatic portal vein of preruminant Holstein calves failed to induce liver abscesses*","authors":"Hannah E. Cox ,&nbsp;Paulo R. Menta ,&nbsp;T.G. Nagaraja ,&nbsp;Whitney L. Crossland ,&nbsp;Kristin E. Hales ,&nbsp;Darren D. Henry ,&nbsp;Clarissa Strieder-Barboza ,&nbsp;Paul R. Broadway ,&nbsp;Jeffery A. Carroll ,&nbsp;Michael A. Ballou ,&nbsp;Vinicius S. Machado","doi":"10.15232/aas.2023-02487","DOIUrl":"10.15232/aas.2023-02487","url":null,"abstract":"<div><h3>Objective</h3><p>Our goal was to determine whether admin- istration of <em>Fusobacterium necrophorum</em> ssp. <em>necrophorum</em> into the jugular or portal vein will induce liver abscesses in preruminant calves.</p></div><div><h3>Materials and Methods</h3><p>The study was performed as 2 experiments according to the inoculation site: jugu- lar vein or hepatic portal circulation. Experiment 1 was performed in 18 calves randomly assigned to receive intra- jugular infusion of saline (CONIV), or 10⁷ (FUSOIV7), 10⁹ (FUSOIV9), and 10¹¹ (FUSOIV11) of <em>F. necrophorum.</em> In experiment 2, 20 calves were assigned to receive intrapor- tal infusion of saline or 10⁶ (FUSOPV6), 10⁸ (FUSOPV8), and 10¹⁰ (FUSOPV10) of <em>F. necrophorum.</em> Blood samples were collected on d 0, 1, 3, 5, 7, and 14 for hematology. Calves were slaughtered 14 d after inoculation and exam- ined for liver gross pathology.</p></div><div><h3>Results and Discussion</h3><p>Neither model produced liver abscesses. However, in experiment 1, inoculation increased monocyte counts in FUSOIV11 calves versus CONIV, FUSOIV7, and FUSOIV9 on d 3 and 5 postchal- lenge. The neutrophil-to-lymphocyte ratio was greater for FUSOIV11 than CONIV and FUSOIV9 on d 7 postchallenge. In experiment 2, inoculation increased monocyte and neutrophils counts in the FUSOPV8 group compared with calves in other groups.</p></div><div><h3>Implications and Applications</h3><p>Contrary to previ- ous reports, intraportal and intrajugular inoculation with <em>F. necrophorum</em> did not produce liver abscesses in preru- minant calves. Further research is necessary to explore alternative methodologies to use preruminant calves in experimental disease models for liver abscesses in cattle.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 3","pages":"Pages 421-429"},"PeriodicalIF":1.5,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000636/pdf?md5=b4a7afd6ee347aed42ef1c1490b5c889&pid=1-s2.0-S2590286524000636-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141230383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Saccharomyces cerevisiae CNCM I-1077 and calcium clinoptilolite zeolite compared with tylosin phosphate and negative control on health, performance, carcass outcomes, and liver abscesses of dairy-beef cross feedlot cattle*","authors":"Miles E. Theurer ,&nbsp;Dale R. Woerner ,&nbsp;Bradley J. Johnson ,&nbsp;Reese Wilson ,&nbsp;Jhones O. Sarturi ,&nbsp;Raghavendra G. Amachawadi ,&nbsp;T.G. Nagaraja ,&nbsp;Jim Simpson ,&nbsp;J. Trent Fox ,&nbsp;Paige Adams ,&nbsp;Kip K. Karges","doi":"10.15232/aas.2023-02475","DOIUrl":"10.15232/aas.2023-02475","url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to evaluate the effects of in-feed, non-antibiotic alternatives (<em>Saccharomyces cerevisiae</em> CNCM I-1077 and calcium clinoptilolite zeolite) on health, growth performance, carcass characteristics, and liver abscesses in dairy-beef cross composites in a commercial feedlot.</p></div><div><h3>Materials and Methods</h3><p>Dairy-beef, intact heifers (n = 2,088; average BW = 334.8 kg) were assigned to 1 of 3 treatment groups: (1) Negative control (no feed-grade antimicrobials for control of liver abscesses; NC); (2) <em>Saccharomyces cerevisiae</em> CNCM I-1077 (0.5 g/heifer per day to provide 1 × 10¹⁰ cfu/heifer per day) and calcium clinoptilolite zeolite (replacing flaked corn at 1.2% on a DM basis; LB), or (3) tylosin phosphate (targeted at a rate of 68 mg/heifer per day; TY). Heifers averaged 228 d on feed at harvest. Individual carcass outcomes and liver scores were captured at harvest.</p></div><div><h3>Results and Discussion</h3><p>Heifers in the TY treatment had reduced DMI, increased G:F, and reduced cost of gain compared with the other treatments. Carcass characteristics were not affected by treatments. Heifers offered LB tended to have fewer total liver abscesses compared with the TY group, whereas NC was intermediate.</p></div><div><h3>Implications and Applications</h3><p>Feedlot performance improved for dairy-beef heifers offered tylosin; however, TY had the greatest percentage of liver abscesses compared with NC. Feeding the combination of <em>Saccharomyces cerevisiae</em> CNCM I-1077 and calcium clinoptilolite as a non-antimicrobial alternative for the mitigation of liver abscesses in dairy-beef females seems to be promising strategy; however, growth performance outcomes may be reduced compared with tylosin.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 3","pages":"Pages 317-328"},"PeriodicalIF":1.5,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000557/pdf?md5=14393fa4a94269cddfae6171fcc6db2c&pid=1-s2.0-S2590286524000557-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141232090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ileal epithelial tissue transcript profiles of steers with experimentally induced liver abscesses*†","authors":"Amanda K. Lindholm-Perry ,&nbsp;Brittney N. Keel ,&nbsp;Kristin E. Hales ,&nbsp;James E. Wells ,&nbsp;Larry A. Kuehn ,&nbsp;John W. Keele ,&nbsp;Matthew S. Crouse ,&nbsp;Dan J. Nonneman ,&nbsp;T.G. Nagaraja ,&nbsp;Ty E. Lawrence ,&nbsp;Raghavendra G. Amachawadi ,&nbsp;Jeff A. Carroll ,&nbsp;Nicole C. Burdick Sanchez ,&nbsp;Paul R. Broadway","doi":"10.15232/aas.2023-02503","DOIUrl":"10.15232/aas.2023-02503","url":null,"abstract":"<div><h3>Objective</h3><p>Liver abscesses in cattle negatively affect production and cause economic losses across the beef cat- tle industry. Recently, a nutritional model has been devel- oped to induce liver abscesses that will provide a method to evaluate the underlying mechanisms driving their de- velopment. The objective of this study was to evaluate gene expression of ileal tissue from calves challenged using the new model.</p></div><div><h3>Materials and Methods</h3><p>In the model, calves were fed a diet to induce ruminal acidosis and were then in- traruminally inoculated with bacteria typically associated with liver abscesses. On d 21, following inoculation, calves were euthanized. Seven of the 13 calves had liver abscess- es. Ileal tissues were collected and total RNA was isolated for RNA-sequencing.</p></div><div><h3>Results and Discussion</h3><p>A total of 26 genes were dif- ferentially expressed in the calves with liver abscesses com- pared with those without. Two genes (<em>COX2</em>, <em>COX3</em>) are components of the cytochrome c oxidase enzyme in the electron chain transport pathway, and both were downreg- ulated among the animals with liver abscesses. Other genes involved in cellular restructuring, transport of compounds across cell membranes, protection of RNA, and protection of protein products were also identified. These functions il- lustrate that there are changes in the ileal epithelium that correspond to the development of liver abscesses.</p></div><div><h3>Implications and Applications</h3><p>We identified sev- eral genes that were differentially expressed in the ileal tissue of calves that developed liver abscesses using the combination of an acidosis-inducing diet and intraruminal inoculation of bacteria. Our results suggest that the ileum has a role in liver abscess development, and future studies to validate the involvement of the mucosal barrier of the ileum are warranted.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 3","pages":"Pages 414-420"},"PeriodicalIF":1.5,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000624/pdf?md5=824739088a490b66c95125ad57378d2c&pid=1-s2.0-S2590286524000624-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141232603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Liver abscesses—New perspectives on a historic fed-cattle issue*†‡","authors":"P.R. Broadway ,&nbsp;T.G. Nagaraja ,&nbsp;T.E. Lawrence ,&nbsp;M.L. Galyean ,&nbsp;K.E. Hales","doi":"10.15232/aas.2023-02498","DOIUrl":"10.15232/aas.2023-02498","url":null,"abstract":"<div><h3>Purpose</h3><p>Our purpose was to provide commentary and new perspectives related to liver abscesses, a historic problem in beef cattle, by describing and discussing docu- mented research, anecdotal observations, and opinions re- garding the causation, detection, and prevention of liver abscesses.</p></div><div><h3>Sources</h3><p>Sources for this article include peer-reviewed, scientific literature; abstracts; proceedings; theses and dissertations; popular press articles; personal communica- tions; and unpublished research data.</p></div><div><h3>Synthesis</h3><p>Liver abscess (LA) disease in cattle is a multifactorial, polymicrobial disease that has wide-rang- ing effects on productivity and profitability throughout all stages of the beef production cycle. The interest in and the study of LA has drastically increased in the past several years, driven largely by efforts to identify alterna- tives to the use of antibiotics for LA control. Although a primary, prevailing theory on LA formation has existed for decades, recent research has led to alternative theo- ries as well as new questions about the role of breed-type specific management, behavior, feed intake patterns, and other factors on LA causation. The inability to detect LA before slaughter complicates research evaluating mitiga- tion strategies and disease etiology. Moreover, the inability to detect LA in live cattle has hindered researcher efforts to understand timing of abscess development or whether an abscess can resolve.</p></div><div><h3>Conclusions and Applications</h3><p>Although the prima- ry pathogens associated with LA have been identified, an effective mitigation strategy has eluded researchers. None- theless, new perspectives and research efforts are needed from both basic and applied perspectives using multidis- ciplinary, collaborative approaches to successfully combat the challenges faced by the beef industry related to LA.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 3","pages":"Pages 237-243"},"PeriodicalIF":1.5,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000478/pdf?md5=397902bb972f142abb3ec6815dbdb679&pid=1-s2.0-S2590286524000478-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141233171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}