Applied Animal Science最新文献

{"title":"Effects of conventional and natural management systems on backgrounding and finishing performance of beef steers","authors":"J. Smith ,&nbsp;E. Darambazar ,&nbsp;G.B. Penner ,&nbsp;N. Erickson ,&nbsp;K. Larson ,&nbsp;J. McKinnon ,&nbsp;D. Damiran ,&nbsp;H.A. (Bart) Lardner","doi":"10.15232/aas.2023-02425","DOIUrl":"https://doi.org/10.15232/aas.2023-02425","url":null,"abstract":"<div><h3>Objective</h3><p>This study evaluated 2 beef cattle manage- ment strategies, conventional (CONV) or natural (NAT), for 3 BW groups at weaning to evaluate growth perfor- mance during backgrounding and finishing and carcass characteristics.</p></div><div><h3>Materials and Methods</h3><p>A total of 240 weaned steers, free of preweaning implants, were allocated into heavy (HV) (290 ± 21 kg; mean ± SD), medium (MD) (247 ± 8 kg), or light (LT) (214 ± 15.6 kg) weight groups over 2 yr. Each weight group (n = 80) was randomly allo- cated to 1 of 2 treatments (n = 40): either conventional or natural (n = 4). Conventional treatments used hormonal implants and feed additives, but the natural treatment did not. Following a 41-d receiving phase, HV steers entered direct finishing, MD steers entered a short backgrounding and finishing, and LT steers entered a long backgrounding, grazing, and finishing, all fed to a shrink weight of 620 kg.</p></div><div><h3>Results and Discussion</h3><p>Steer ADG was 19% and 22% greater for MD- and LT-CONV, respectively, at backgrounding, compared with NAT. The G:F was 20% greater for HV- and MD-CONV at finishing and 25% greater for LT-CONV at backgrounding. The HV-, MD-, and LT-CONV took 50, 71, and 59 fewer days on feed, respectively, to finish, relative to NAT. The rib-eye area were greatest in HV-CONV, and NAT produced greater marbling, QG (AAA), and backfat thickness and had a greater proportion of liver abscesses.</p></div><div><h3>Implications and Applications</h3><p>Steers managed without performance-enhancing technologies under west- ern Canadian conditions will have lower ADG, G:F, and YG1, but greater days on feed to a target weight, AAA grade, marbling, and backfat thickness, than convention- ally-managed steers.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000235/pdf?md5=cb9ad1de0a2c0fc323521a5b56abf16f&pid=1-s2.0-S2590286524000235-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140295959","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":"Activity and rumination of implanted Charolais × Angus feedlot steers versus non-implanted counterparts consuming 3 levels of roughage throughout a 361-day feeding duration","authors":"Sierra L. Pillmore ,&nbsp;Tylo J. Kirkpatrick ,&nbsp;Kaitlyn R. Wesley ,&nbsp;Kimberly B. Cooper ,&nbsp;Forest L. Francis ,&nbsp;Travis C. Tennant ,&nbsp;Wade T. Nichols ,&nbsp;John P. Hutcheson ,&nbsp;Ty E. Lawrence","doi":"10.15232/aas.2023-02517","DOIUrl":"https://doi.org/10.15232/aas.2023-02517","url":null,"abstract":"<div><h3>Objective</h3><p>Rumination and activity of growing feedlot steers were evaluated in response to growth-promoting implant administration, feeding duration, and dietary rough- age.</p></div><div><h3>Materials and Methods</h3><p>Charolais × Angus steers (n = 80) were randomized to harvest (1, 42, 84, 126, 168, 210, 252, 294, 336, or 378 d on feed) and implant treatment (REV: Revalor-XS on d 0 and d 190; CON: no implant). Activity and rumination were objectively monitored via accelerometers attached to the left ear. Steers consumed 3 rations throughout the study: starter (38.5% roughage), intermediate (23% roughage), and finishing (8.5% rough- age). Data were logged in 2-h increments from 77 steers across 361 d and analyzed using mixed models.</p></div><div><h3>Results and Discussion</h3><p>Rumination and activity varied within 24-h, exhibiting bimodal patterns; rumination peaked at 0600 and 1400 h and troughed at 1000 and 1800 h. Activity peaked at 0800 and 1800 h and troughed at 0400, 1200 to 1400, and 2200 h. Steers administered REV ruminated less (331 vs. 354 min/d) than CON; however, activity was similar between treatments. Treatment × roughage interactions occurred for rumination and activity. Rumination tended to be greater for CON steers consuming 38.5% than CON steers consuming 23% roughage, furthermore, CON steers ruminated more than REV when consuming 8.5% roughage. Implanted and non-implanted steers ruminated less as roughage inclusion decreased from 38.5% and 23% to 8.5% (457 and 439 vs. 317 min/d, respectively) in the finishing ration. Activity was greatest for steers consuming 38.5% roughage and was similar between treatments; however, activity decreased upon transition to 23% and 8.5% roughage. Observed surges and declines in activity can be attributed to processing days and weather events. Implanted steers consuming 8.5% roughage were more active (342 vs. 337 and 333 min/d) than CON and REV steers consuming 23% roughage.</p></div><div><h3>Implications and Applications</h3><p>In conclusion, rumination and activity are responsive to hour of day, dietary roughage and growth-promoting implants.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000302/pdf?md5=b8d3c812f141091d4075ff2bae8ee149&pid=1-s2.0-S2590286524000302-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140296050","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":"US wool industry perceptions of digital record keeping and wool supply-chain traceability","authors":"C.E. Newman ,&nbsp;C.L. Gifford ,&nbsp;D.P. Anderson ,&nbsp;J.D. Scasta ,&nbsp;W.C. Stewart","doi":"10.15232/aas.2023-02496","DOIUrl":"https://doi.org/10.15232/aas.2023-02496","url":null,"abstract":"<div><h3>Objective</h3><p>The objectives of this research were to assess the awareness and perceptions of technology currently available to the US sheep industry, to determine how each industry segment prioritizes data records, to understand what level of premiums are needed and realistic, and to assess changes by industry segment and operation size.</p></div><div><h3>Materials and Methods</h3><p>An online survey was distributed at the 2022 American Sheep Industry Association (ASI) Convention and through the University of Wyoming Sheep Extension and ASI Emerging Entrepreneurs social media pages. Respondents were asked demographic questions and specific segment questions that assessed knowledge of blockchain, importance of records, and current adoption of technology. All descriptive and ANOVA analyses used R statistical procedures (R Core Team; version 2023.03.0). Least squares means were calculated, and the glm procedure of R was used to develop a binary logit model to assess statistical probabilities. Significance was considered at α = 0.05.</p></div><div><h3>Results and Discussion</h3><p>A total of 61 responses were acquired (n = 52 producers; n = 9 wool warehousers/ processors), representing operations in 19 US states and Ontario, Canada. Respondents indicated they are somewhat familiar with using blockchain technology for tracking records of importance. Adoption of electronic identification (EID) technology and digital record keeping were significant by operation size, with inflection points for operations with &lt;99 head or &gt;2,000 head (i.e., extremes). A market premium 8.1–12% over base price is needed to submit a raw wool core test into a blockchain-based system, but wool warehousers/processors are willing to pay a premium to have access to the records on a blockchain- based system at 4.1–8% over base price.</p></div><div><h3>Implications and Applications</h3><p>Producers and wool warehousers/processors are somewhat familiar with block-chain technology for tracking records of importance, but producer adoption of the current technologies (e.g., EID, software) is limited. Adoption of current management technologies is influenced by operation size, so further work should be conducted to determine the largest barriers to adoption. Further adoption of the current technologies is needed before blockchain technology can be used to its full potential in the sheep industry.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000284/pdf?md5=3d43f919c27e406983403fa3bcabf54a&pid=1-s2.0-S2590286524000284-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140295861","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":"Optimization of indigestible neutral and acid detergent fiber measurement protocols*","authors":"M.R. Beck ,&nbsp;M.L. Griffin ,&nbsp;J.A. Proctor ,&nbsp;R. Foster ,&nbsp;N.S. Long ,&nbsp;J.K. Smith ,&nbsp;V.N. Gouvêa","doi":"10.15232/aas.2023-02521","DOIUrl":"https://doi.org/10.15232/aas.2023-02521","url":null,"abstract":"<div><h3>Objective</h3><p>The objective was to evaluate the effect of using a diet predigestion (PD) of HCl and pepsin along with different in situ ruminal incubation lengths on indi- gestible NDF (INDF) and ADF (IADF) content recovery from diet and fecal samples.</p></div><div><h3>Materials and Methods</h3><p>Diet and total fecal collec- tion samples from steers fed a high-roughage starter or a low-roughage finisher diet were collected from a larger experiment. Diet samples either underwent PD or not (NPD). Then, diet and fecal samples were ruminally in- cubated for 72, 96, 120, or 288-h. After incubation, NDF or ADF protocols were conducted to determine INDF and IADF.</p></div><div><h3>Results and Discussion</h3><p>For PD, a 120-h ruminal incubation length was needed to achieve fecal recoveries that were not different from 100% for all marker by diet combinations. For NPD, a 288-h incubation was required to achieve 100% fecal recovery for all diet by marker com- binations, except for IADF with the finisher diet. A 120-h incubation resulted in the highest agreement [Lin’s concor- dance correlation coefficient (CCC) ≥0.90] with observed dry matter digestibility (DMD) for INDF and IADF for PD. With NPD, a 288-h incubation was needed to achieve estimates of DMD with excellent agreement (CCC ≥0.89) for INDF and IADF.</p></div><div><h3>Implications and Applications</h3><p>Based on these re- sults, PD followed by a 120-h ruminal incubation shortens time requirements and provides acceptable measurements of INDF and IADF concentrations in feeds and feces. For NPD a 288-h ruminal incubation length is required.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S259028652400020X/pdfft?md5=d1b1d9ae7c52f0f483659ed67b0c56d8&pid=1-s2.0-S259028652400020X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140295956","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":"Applicability of an automated supplement feeder to dose titanium dioxide to estimate forage intake, fecal output, and diet digestibility of beef cattle","authors":"Beatriz Ramos,&nbsp;Georgget Banchero,&nbsp;Alejandro La Manna,&nbsp;Maria Eugênia Andrighetto Canozzi,&nbsp;Enrique Fernández,&nbsp;Juan Clariget","doi":"10.15232/aas.2023-02448","DOIUrl":"https://doi.org/10.15232/aas.2023-02448","url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to evaluate 2 methods of external marker dosing, at 2 levels of forage allowance, to estimate forage intake in beef cattle.</p></div><div><h3>Materials and Methods</h3><p>Sixteen Aberdeen Angus steers (mean age of 18 mo; 350 ± 9 kg BW), kept in in- dividual pens, were used in a quadruplicated 4 × 4 Latin square design experiment, in a 2 × 2 factorial arrange- ment. The factors were forage allowance level (4 vs. 7 kg DM/d of alfalfa plus orchard grass haylage) and supple- ment feeding method (manual vs. automatic). A supple- ment consisting of 2 kg DM of pelleted corn with 1% ti- tanium dioxide (TiO₂) per day was offered to each steer. Total DMI and diet DM digestibility were estimated using the dual-marker technique, with acid insoluble ash (AIA; 2 different methods) or ADL used as the internal marker. Fecal output was estimated by TiO₂ concentration using feces from the daily total fecal collection (TFC) samples and others from a morning subsample. The TFC was car- ried out individually and daily during the last 4 d of each 21-d period.</p></div><div><h3>Results and Discussion</h3><p>The overall mean recovery of TiO₂ was 104% (SD: 0.05; range: 101–107%). Fecal subsamples obtained in the morning overestimated fecal production with no difference between dosing methods. The DM digestibility was overestimated with AIA and ADL. The estimation of DM digestibility by ADL was closer than AIA to those obtained by TFC, without differ- ences between the 2 AIA techniques. The overestimation of forage intake using the dual-marker technique was more affected by the overvalued DM digestibility using the in- ternal markers than by fecal production using the external marker, without the effect of the dosing method.</p></div><div><h3>Implications and Applications</h3><p>It is viable and reli- able to automatically supply pelleted corn with TiO₂ for fecal production estimation. The accuracy could be im- proved by obtaining at least 2 fecal samples during the day. Under the current experimental conditions, ADL is more accurate than AIA for estimating DM digestibility when the diet offered to cattle is based on alfalfa plus or- chard grass haylage and concentrate.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000211/pdf?md5=f324661a1b53a0522dc31080de60cb66&pid=1-s2.0-S2590286524000211-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140295957","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":"Evaluating supplementation programs for growing calves grazing bermudagrass pastures","authors":"A.M. Womack ,&nbsp;PAS,&nbsp;E.B. Kegley ,&nbsp;PAS,&nbsp;Shane Gadberry ,&nbsp;PAS,&nbsp;T. Hess ,&nbsp;D. Hubbell ,&nbsp;P.A. Beck ,&nbsp;PAS","doi":"10.15232/aas.2023-02494","DOIUrl":"https://doi.org/10.15232/aas.2023-02494","url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to determine gain in response to hand-fed (HF) or self-fed (SF) summer supplementation programs at the University of Arkansas Livestock and Forestry Research Station, on twenty 0.81-ha common bermudagrass (<em>Cynodon dactylon</em> [L.] Pers.) pastures at a stocking rate of 6.17 calves/ha (BW ± SD = 247 ± 24.6) over 3 yr.</p></div><div><h3>Materials and Methods</h3><p>This experiment was designed in a 2 × 2 + 1 factorial arrangement of treatments including control (CON), with only free-choice mineral; HF, 1.13 kg/d byproduct-based supplement offered only late summer (LS) or all summer (AS); or SF tub supplement (PVM Cattle Tub, Positive Feed Ltd., Sealy, TX) either LS or AS. The HF supplement in yr 1 was a 50:50 blend of soybean hulls and corn gluten feed, in yr 2 an extruded dried distillers grains cube (MasterHand Milling, Lexington, NE) was used, and in yr 3 corn gluten feed was the HF supplement. Data were analyzed as a generalized randomized complete block design using the mixed procedure of SAS (SAS Institute Inc., Cary, NC). Fixed effects in the model included supplementation treatment, year, and year × treatment interaction.</p></div><div><h3>Results and Discussion</h3><p>Even though different HF supplements were used each year, there were no year × treatment interactions. Early summer ADG was greater for HFAS than CON and SFAS, whereas supplemental efficiency (kg added gain/kg supplement) in early summer was less for SFAS than HFAS. Late summer ADG was greater for HF treatments than SF treatments and CON, whereas SF did not differ among supplement treatments. Cost of added gain was $28.33 and $16.14/kg for SFAS and SFLS, respectively, compared with $3.32 and $1.68/ kg for HFAS and HFLS, respectively.</p></div><div><h3>Implications and Applications</h3><p>Calves on this experiment did not respond as expected to the SF supplement, likely because the bermudagrass pastures in this experiment averaged over 13% CP and were in excess of 10% even in the LS sampling periods. Depending on supplement delivery costs, the most cost-effective way to add gain with supplement to growing calves grazing bermudagrass pasture is by HF.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S259028652400017X/pdf?md5=e7001816153191a8ae626b8ebab6eca2&pid=1-s2.0-S259028652400017X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140296051","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: Effects of conversion of farmland to an integrated beef cattle grazing operation and water use in the Southern Plains and Ogallala Aquifer of the USA","authors":"Miles E. Theurer ,&nbsp;Jonathan Aguilar ,&nbsp;Rachael Clews ,&nbsp;J. Trent Fox ,&nbsp;Gina Gigot ,&nbsp;Marc Gigot ,&nbsp;Tom M. Jones ,&nbsp;Darrin McGraw ,&nbsp;Justin W. Waggoner","doi":"10.15232/aas.2023-02506","DOIUrl":"https://doi.org/10.15232/aas.2023-02506","url":null,"abstract":"<div><h3>Purpose</h3><p>The objectives were to quantify the amount of water savings by converting farmland to an integrated cattle grazing operation through farming practices and cattle requirements, quantify estimated water savings from Thunderstruck Farms over a 20-yr period in relationship to a nearby municipality, and evaluate cattle water intake in backgrounding and feedlot phases.</p></div><div><h3>Sources</h3><p>Thunderstruck Farms is located near Garden City, Kansas, which has 3,035 irrigated hectares with the primary water source coming from the Ogallala Aquifer. In 2018 Thunderstruck Farms entered all its irrigated land into a water conservation area (WCA) to conserve water resources, and all crops grown are used for silage, hay, or pasture to support the dairy and feedyard enterprises in the region. Historical water and nitrogen use from Thunderstruck Farms was evaluated from 2013 through 2022. Light-weight beef cattle (181–272 kg) graze these irrigated pastures (approximately 120 d). Following the grazing season, the cattle are finished at Hy-Plains Feedyard (Montezuma, KS).</p></div><div><h3>Synthesis</h3><p>Thunderstruck Farms is allocated 22.9 billion liters of water annually for stock water and irrigation purposes. Thunderstruck Farms used 50.8 billion liters less water than allocated, with 57.8% of the conservation occurring during the 5-yr period of the WCA. Average nitrogen administration has decreased 39% per year since entering into the WCA. During the same period, Thunderstruck Farms has produced 2.8 million kilograms of total weight gain of beef; beef cattle were then transferred to Hy-Plains Feedyard to finish. Based on the calculations from this research, the average amount of water saved over a 4-yr period by decreasing commodity resource use by grazing cattle would average 1.1 billion liters of water each year per 4,047 ha. On average, cattle consumed 17.94 L/ head per day while grazing. Peak monthly water use corresponded with average ambient temperature peak during the summer months.</p></div><div><h3>Conclusions and Applications</h3><p>Integrated grazing systems reduce the inputs required for cattle to reach a slaughter endpoint. They also may improve soil health. All of these practices result in more water availability for surrounding municipalities and allow for a thriving local economy.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000272/pdf?md5=e2b9dc99bcab33977a97e1532ee87608&pid=1-s2.0-S2590286524000272-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140295860","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":"Classification of postpartum beef cows as estrous cycling or anestrous through the use of estrus detection patches prior to the start of the breeding season","authors":"E.G. Smith ,&nbsp;K.R. Ricardo ,&nbsp;G.M. VanWye ,&nbsp;L.J. Palcheff ,&nbsp;R.C. Bonacker ,&nbsp;C.M. Andersen ,&nbsp;J.M. Thomas","doi":"10.15232/aas.2023-02474","DOIUrl":"https://doi.org/10.15232/aas.2023-02474","url":null,"abstract":"<div><h3>Objective</h3><p>Two experiments were designed to evaluate use of estrus detection patches (Estrotect Breeding Indi- cators; Hermitage, TN) applied to postpartum cows 24 d before estrus synchronization as a diagnostic tool to clas- sify postpartum beef cows as estrous cycling or anestrous.</p></div><div><h3>Materials and Methods</h3><p>Estrous cyclicity was de- termined via blood samples (experiment 1) or transrectal ovarian ultrasonography (Experiment 2). In Experiment 1, blood samples were collected from 257 cows 10 d before, and coincident with the start of synchronization. Serum progesterone concentrations were determined via radioim- munoassay; cows were considered cycling if one or both samples exceeded 0.5 ng/mL.</p></div><div><h3>Results and Discussion</h3><p>Based on progesterone, 55% were cycling at the start of estrus synchronization. Use of activated patches to infer cyclicity resulted in 85% sensi- tivity and 79% specificity. However, 75% of cows presented with missing patches. If missing patches were considered activated, sensitivity was 96% but specificity was 16%, In Experiment 2, estrous cyclicity status was determined for 269 cows via transrectal ovarian ultrasonography coinci- dent with the start of estrus synchronization. Cows were classified as cycling based on the presence of a corpus lu- teum. Based on transrectal ovarian ultrasonography, 59% (161/269) were cycling at the start of estrus synchroniza- tion. Of cows receiving patches, 95% (256/269) retained patches for the full 24-d period. Use of activated patches to infer cyclicity resulted in 89% sensitivity and 68% speci- ficity in Experiment 2.</p></div><div><h3>Implications and Applications</h3><p>Estrus detection patches are a sensitive tool to classify postpartum cows as cycling before the start of the breeding season; however, patch retention could limit application for this purpose.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000223/pdf?md5=d5c8deeb0896a2c4b71d2f93c6c47044&pid=1-s2.0-S2590286524000223-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140295958","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":"A cooperative study assessing the effects of a second iron injection administered before weaning on growth performance, hematological status, and tissue mineral concentrations of nursery pigs*","authors":"T.B. Chevalier ,&nbsp;O. Adeola ,&nbsp;S.D. Carter ,&nbsp;C.R. Dove ,&nbsp;M.J. Estienne ,&nbsp;C.L. Levesque ,&nbsp;C.V. Maxwell ,&nbsp;T. Tsai ,&nbsp;M.D. Lindemann","doi":"10.15232/aas.2023-02480","DOIUrl":"https://doi.org/10.15232/aas.2023-02480","url":null,"abstract":"<div><h3>Objective</h3><p>A study involving 7 experiment stations evaluated the effects of a second iron injection adminis- tered before weaning on growth and hematological mea- sures of pigs.</p></div><div><h3>Materials and Methods</h3><p>Pigs (n = 514) were given an iron injection (100–200 mg) on the first day of life. Piglets were then allotted to pairs of similar-weight, same- sex siblings 3 to 5 d before weaning (on d 18–24) with one piglet from each pair receiving a second iron injection. All pigs received common station-specific postweaning diets. Data were subjected to ANOVA with the model contain- ing the terms treatment, station, pair within station, and treatment × station interaction.</p></div><div><h3>Results and Discussion</h3><p>Postweaning ADG was greater for the added-injection group during during 0 to 14 d after weaning, but the response (212.5 vs. 202.6 g) was largely influenced by a single station as evidenced by a treatment × station interaction. The tendency for a treatment × station interaction for overall ADG (d −4 to 28) indicated that iron status was not the most limiting factor for growth at all stations. Hemoglobin concentra- tion was greater for the added-injection group at weaning and d 14 after weaning.</p></div><div><h3>Implications and Applications</h3><p>An additional iron injection before weaning may lead to improved early nursery growth; however, the beneficial effects of an additional iron injection are not universal and are likely dependent on unique herd characteristics including timing and total dosage of iron injections as well as nursery diet supple- mentation.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000193/pdf?md5=ec4536ff629a141b409a222f520c5920&pid=1-s2.0-S2590286524000193-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140296034","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 short-term nutritional increase before artificial insemination on average daily gain and reproductive efficiency in March-calving beef heifer development systems","authors":"L.F. Tadich ,&nbsp;R.E.S. Rogers ,&nbsp;R.N. Funston","doi":"10.15232/aas.2023-02399","DOIUrl":"https://doi.org/10.15232/aas.2023-02399","url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to evaluate increased nu- tritional energy before AI on BW, ADG, and reproductive efficiency in heifers developed on range or in a drylot.</p></div><div><h3>Materials and Methods</h3><p>A 3-yr study used Angus crossbred heifers (n = 100/yr) near North Platte, Nebras- ka. Heifers were stratified by BW and assigned to 1 of 3 treatments. During winter development (131 ± 3.5 d/yr), heifers grazed upland range (RANGE) or were fed a drylot diet in 2 pens with a targeted gain of 0.68 kg/d to achieve 65% of mature BW (6.35 kg/head per day hay, 2.27 kg/ head per day wet corn gluten feed, and 0.34 kg/head per day supplement). Thirty-three days before AI, one dry- lot group remained on this diet (DLLO) while the other (DLHI) received an additional 4.08 kg/head per day wet corn gluten feed. Heifers developed on RANGE received 0.45 kg/head per day of a 29% CP, dried distillers grain– based pellet until 38 d before AI, when they were fed the DLLO diet.</p></div><div><h3>Results and Discussion</h3><p>Prebreeding BW was great- er for DLHI (375 ± 3.4 kg) and DLLO (363 ± 3.4 kg) compared with RANGE (312 ± 3.4 kg), but breeding ADG was greater for RANGE (0.69 ± 0.01 kg) compared with DLHI (0.35 ± 0.02 kg) and DLLO (0.37 ± 0.02 kg). Pregnancy rates to AI were similar among DLHI (69%), DLLO (63%), and RANGE (49%); final pregnancy rates tended to be different: DLHI (96%), DLLO (95%) and RANGE (84%). Calving rate and calving in the first 21 d was similar.</p></div><div><h3>Implications and Applications</h3><p>Greater nutrient and energy intake for DLHI and DLLO led to greater BW and ADG compared with RANGE, but short-term nutri- tional increase had no effect on pregnancy rate to AI nor final pregnancy rates.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000260/pdf?md5=66698a5d08bd784398b8a208e0eeb378&pid=1-s2.0-S2590286524000260-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140295859","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}