P.A. Beck , M.R. Beck , D. Hubbell III , T. Hess , A.P. Foote , M.S. Gadberry , E.B. Kegley
Objectives
Our objective was to determine the effects of feeding free-choice bermudagrass (Cynodon dactylon) round-bale silage to growing calves stocked at increasing rates and grazing wheat (Triticum aestivum L.) pasture in north-central Arkansas.
Materials and Methods
In the fall and winter, steers were stocked at 2.47 steers/ha without bermudagrass bale- age (HCON) or were stocked at 1× (H1.0), 1.5× (H1.5), or 2× (H2.0) the HCON stocking rate with ad libitum access to bermudagrass round-bale wrapped silage. Each pasture was stocked at 5.6 steers/ha (8 steers per pasture) in the spring, with continued ad libitum silage offered to pastures in the H1.0, H1.5, and H2.0 fall treatments.
Results and Discussion
When steers in H1.0 were offered ad libitum bermudagrass haylage with no change in stocking rate, ADG were increased by 12% over HCON to 1.43 kg/d. As stocking rate increased in the fall and winter from H1.0 to H1.5 and H2.0 treatments, ADG decreased. The ADG of H1.5 (1.25 kg/d) did not differ from HCON (1.27 kg/d), and ADG of H2.0 (1.12 kg/d) was reduced by 12% compared with HCON. There was no effect of of- fering supplemental round-bale haylage on ADG of steers grazing graze-out wheat pastures. Steer grazing days per hectare increased when round-bale haylage was offered, even though stocking rates were not increased during this part of the experiment. Total system net returns did not differ between HCON and H1.0. However, total system net return ($876/ha) was greater for H2.0 compared with H1.0 ($571/ha), whereas H1.5 ($693/ha) was intermediate, dif- fering from neither H1.0 nor H2.0.
Implications and Applications
Feeding moderate- quality roughage during the fall can increase production stability and thus improve economic stability of the wheat stocker enterprise. There does not appear to be an eco- nomic advantage of feeding moderate-quality roughage ad libitum to stockers grazing spring wheat when producers decide to forgo wheat grain harvest and steers graze out the wheat crop.
{"title":"Can moderate-quality bermudagrass baleage be used to stretch wheat pasture?*","authors":"P.A. Beck , M.R. Beck , D. Hubbell III , T. Hess , A.P. Foote , M.S. Gadberry , E.B. Kegley","doi":"10.15232/aas.2023-02466","DOIUrl":"https://doi.org/10.15232/aas.2023-02466","url":null,"abstract":"<div><h3>Objectives</h3><p>Our objective was to determine the effects of feeding free-choice bermudagrass (<em>Cynodon dactylon</em>) round-bale silage to growing calves stocked at increasing rates and grazing wheat (<em>Triticum aestivum</em> L.) pasture in north-central Arkansas.</p></div><div><h3>Materials and Methods</h3><p>In the fall and winter, steers were stocked at 2.47 steers/ha without bermudagrass bale- age (HCON) or were stocked at 1× (H1.0), 1.5× (H1.5), or 2× (H2.0) the HCON stocking rate with <em>ad libitum</em> access to bermudagrass round-bale wrapped silage. Each pasture was stocked at 5.6 steers/ha (8 steers per pasture) in the spring, with continued <em>ad libitum</em> silage offered to pastures in the H1.0, H1.5, and H2.0 fall treatments.</p></div><div><h3>Results and Discussion</h3><p>When steers in H1.0 were offered <em>ad libitum</em> bermudagrass haylage with no change in stocking rate, ADG were increased by 12% over HCON to 1.43 kg/d. As stocking rate increased in the fall and winter from H1.0 to H1.5 and H2.0 treatments, ADG decreased. The ADG of H1.5 (1.25 kg/d) did not differ from HCON (1.27 kg/d), and ADG of H2.0 (1.12 kg/d) was reduced by 12% compared with HCON. There was no effect of of- fering supplemental round-bale haylage on ADG of steers grazing graze-out wheat pastures. Steer grazing days per hectare increased when round-bale haylage was offered, even though stocking rates were not increased during this part of the experiment. Total system net returns did not differ between HCON and H1.0. However, total system net return ($876/ha) was greater for H2.0 compared with H1.0 ($571/ha), whereas H1.5 ($693/ha) was intermediate, dif- fering from neither H1.0 nor H2.0.</p></div><div><h3>Implications and Applications</h3><p>Feeding moderate- quality roughage during the fall can increase production stability and thus improve economic stability of the wheat stocker enterprise. There does not appear to be an eco- nomic advantage of feeding moderate-quality roughage <em>ad libitum</em> to stockers grazing spring wheat when producers decide to forgo wheat grain harvest and steers graze out the wheat crop.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 1","pages":"Pages 1-13"},"PeriodicalIF":1.5,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000016/pdf?md5=bb9f303099fe93f2df2cf4923eb96d81&pid=1-s2.0-S2590286524000016-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139653010","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}
Carl A. Old , Ian J. Lean , Heidi A. Rossow , Daniel W. Shike
Objective
Our objective was to evaluate model structure choice on estimates of efficiency, based on residual feed intake, and thereby cattle profitability.
Materials and Methods
Efficiencies were compared for 2 models using data from 7 studies (509 cattle). Model 1 DMI were estimated using ordinary least squares as f(ADG and BW0.750). Model 2 was a multivariable Bayesian model; DMI was f(ADG, BW0.750 and BW). For model 2, DMI, BW, and ADG were ranked by model 1 residuals categorized in quintile to evaluate whether information found in residuals related to composition of gain or maintenance.
Results and Discussion
Efficiency rankings lacked concordance and predictive value between models, suggesting that ordinary least squares, Bayesian, or both frameworks lack utility to predict efficiency. With the exception of 1 data set, DMI was better predicted in the Bayesian framework. Estimated recovered energy (Mcal/d) in model 2 was less for cattle in quintile 1 than in quintile 5 for 4 of 7 data sets and numerically less for 6 of 7 data sets. Estimated maintenance in model 2 was less (quintiles 1 vs. 5) for 5 of 7 data sets. Substantial information existed in model 1 residuals regarding differences in composition of gain and maintenance not found in model 2 residuals.
Implications and Applications
Differing efficiencies between models indicate that residuals are properties of models, not cattle. Selection of cattle with less empty body fat may not be desirable from an economic standpoint.
{"title":"Modeling differences in feed intake and efficiency: Growing and finishing beef cattle","authors":"Carl A. Old , Ian J. Lean , Heidi A. Rossow , Daniel W. Shike","doi":"10.15232/aas.2023-02443","DOIUrl":"https://doi.org/10.15232/aas.2023-02443","url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to evaluate model structure choice on estimates of efficiency, based on residual feed intake, and thereby cattle profitability.</p></div><div><h3>Materials and Methods</h3><p>Efficiencies were compared for 2 models using data from 7 studies (509 cattle). Model 1 DMI were estimated using ordinary least squares as <em>f</em>(ADG and BW<sup>0.750</sup>). Model 2 was a multivariable Bayesian model; DMI was <em>f</em>(ADG, BW<sup>0.750</sup> and BW). For model 2, DMI, BW, and ADG were ranked by model 1 residuals categorized in quintile to evaluate whether information found in residuals related to composition of gain or maintenance.</p></div><div><h3>Results and Discussion</h3><p>Efficiency rankings lacked concordance and predictive value between models, suggesting that ordinary least squares, Bayesian, or both frameworks lack utility to predict efficiency. With the exception of 1 data set, DMI was better predicted in the Bayesian framework. Estimated recovered energy (Mcal/d) in model 2 was less for cattle in quintile 1 than in quintile 5 for 4 of 7 data sets and numerically less for 6 of 7 data sets. Estimated maintenance in model 2 was less (quintiles 1 vs. 5) for 5 of 7 data sets. Substantial information existed in model 1 residuals regarding differences in composition of gain and maintenance not found in model 2 residuals.</p></div><div><h3>Implications and Applications</h3><p>Differing efficiencies between models indicate that residuals are properties of models, not cattle. Selection of cattle with less empty body fat may not be desirable from an economic standpoint.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 1","pages":"Pages 40-55"},"PeriodicalIF":1.5,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000041/pdf?md5=f272ab46254dac779289d028f016091d&pid=1-s2.0-S2590286524000041-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139653015","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}
Christian H. Ponce , Jenny J. Jennings , Michael S. Brown , Beverly E. Meyer , N. Andy Cole
Objective
Wet distillers grains with solubles (WDGS) are a common feed ingredient used in cattle finishing diets. However, the NE values of WDGS have not been clearly delineated, and there may be an interaction between grain processing method and the feeding value of WDGS. This study was conducted to evaluate the relative NE values of WDGS and to evaluate possible associative effects between WDGS and steam-flaked corn (SFC) on energy and nitrogen utilization by finishing beef steers.
Materials and Methods
Four British crossbred steers were used in a 4 × 4 Latin square design in which steers were fed 1 of 4 diets: (1) a basal 86% concentrate diet fed a 1× maintenance (B), (2) the basal diet + SFC fed at 1.5× maintenance (B+SFC), (3) the basal diet + WDGS fed at 1.5× maintenance (B+WDGS), and (4) the basal diet + a 50:50 blend of WDGS and SFC fed at 1.5× maintenance (BLEND). Each period of the Latin square was 28 d in length with steers confined to indirect open- circuit respiration chambers the last 5 d of each period. Nutrient digestibility, urinary nutrient excretion, methane and carbon dioxide production, and heat production were determined during the last 5 d of each period. Dietary and ingredient (SFC or WDGS) TDN, DE, ME, and NE values were calculated.
Results and Discussion
The digestibility of DM and OM of B+SFC was greater than that of B+WDGS, with the BLEND diet being intermediate. Nitrogen balance was numerically greater for B+WDGS than for B+SFC, with BLEND being intermediate. Digestible energy, ME, and energy retention were greater for B+SFC than for B+WDGS, with BLEND being intermediate. The experi- mental method used affected the TDN, DE, ME, and NE values of diets, SFC, and WDGS. There were negative associative effects (−1% to −8.0%) between SFC and WDGS for energy values. Actual DE:TDN averaged 4.11 Mcal of DE/kg of TDN, which is less than the 4.4 value used by NASEM (2016). The DE:digestible OM ratio av- eraged 4.54 Mcal/kg, and the digestible OM:TDN ratio averaged 90.2.
Implications and Applications
Our results suggest that within the range of rations fed in this study, the NE values for WDGS by NASEM (2016) may overestimate their relative NE (15%) when fed in diets based on SFC.
{"title":"Effects of steam-flaked corn and wet distillers grains with solubles on energy metabolism of finishing beef steers*","authors":"Christian H. Ponce , Jenny J. Jennings , Michael S. Brown , Beverly E. Meyer , N. Andy Cole","doi":"10.15232/aas.2023-02439","DOIUrl":"https://doi.org/10.15232/aas.2023-02439","url":null,"abstract":"<div><h3>Objective</h3><p>Wet distillers grains with solubles (WDGS) are a common feed ingredient used in cattle finishing diets. However, the NE values of WDGS have not been clearly delineated, and there may be an interaction between grain processing method and the feeding value of WDGS. This study was conducted to evaluate the relative NE values of WDGS and to evaluate possible associative effects between WDGS and steam-flaked corn (SFC) on energy and nitrogen utilization by finishing beef steers.</p></div><div><h3>Materials and Methods</h3><p>Four British crossbred steers were used in a 4 × 4 Latin square design in which steers were fed 1 of 4 diets: (1) a basal 86% concentrate diet fed a 1× maintenance (B), (2) the basal diet + SFC fed at 1.5× maintenance (B+SFC), (3) the basal diet + WDGS fed at 1.5× maintenance (B+WDGS), and (4) the basal diet + a 50:50 blend of WDGS and SFC fed at 1.5× maintenance (BLEND). Each period of the Latin square was 28 d in length with steers confined to indirect open- circuit respiration chambers the last 5 d of each period. Nutrient digestibility, urinary nutrient excretion, methane and carbon dioxide production, and heat production were determined during the last 5 d of each period. Dietary and ingredient (SFC or WDGS) TDN, DE, ME, and NE values were calculated.</p></div><div><h3>Results and Discussion</h3><p>The digestibility of DM and OM of B+SFC was greater than that of B+WDGS, with the BLEND diet being intermediate. Nitrogen balance was numerically greater for B+WDGS than for B+SFC, with BLEND being intermediate. Digestible energy, ME, and energy retention were greater for B+SFC than for B+WDGS, with BLEND being intermediate. The experi- mental method used affected the TDN, DE, ME, and NE values of diets, SFC, and WDGS. There were negative associative effects (−1% to −8.0%) between SFC and WDGS for energy values. Actual DE:TDN averaged 4.11 Mcal of DE/kg of TDN, which is less than the 4.4 value used by NASEM (2016). The DE:digestible OM ratio av- eraged 4.54 Mcal/kg, and the digestible OM:TDN ratio averaged 90.2.</p></div><div><h3>Implications and Applications</h3><p>Our results suggest that within the range of rations fed in this study, the NE values for WDGS by NASEM (2016) may overestimate their relative NE (15%) when fed in diets based on SFC.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"40 1","pages":"Pages 14-28"},"PeriodicalIF":1.5,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286524000028/pdf?md5=b3395b9deb94b0f93a862ee0094e2292&pid=1-s2.0-S2590286524000028-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139653012","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}
P. Woli , C.R. Long , L.O. Tedeschi , F.M. Rouquette Jr
Objective
Our objective was to develop an age × BCS factor (ABCf) that could be used to estimate the ADG of stockers grazing bermudagrass (Cynodon dactylon [L.] Pers.) pasture as influenced by their age and BCS at the onset of stocking, hereafter referred to as the initial age and BCS.
Materials and Methods
Data on the ADG of stock- ers grazing bermudagrass in the southern United States were obtained from multiple sources, including literature, for various scenarios of initial age × BCS. Then, an ABCf for each age × BCS scenario was calculated by dividing its ADG by the ADG of calves 7 to 10 mo old with BCS of 5, a standard age × BCS scenario. Finally, an ABCf equa- tion was derived by regressing the ABCf values against the BCS values under each age group.
Results and Discussion
We derived the following ABCf equation to estimate the ADG of a stocker grazing bermudagrass pasture as ADG′ = ADG × ABCf, where and BCS on ADG of stockers grazing bermudagrass pas- ture. Current ADG indices or estimates do not account for the interacting effects of initial age and BCS. By incorpo- rating the ABCf into an ADG prediction system, the scien- tific community and stakeholders can more accurately as- sess the effects of these attributes on animal performance and develop appropriate purchase pricing and supplemen- tation strategies before and during stocking.
{"title":"Estimating the daily weight gain of beef stocker cattle grazing bermudagrass as affected by initial age and body condition","authors":"P. Woli , C.R. Long , L.O. Tedeschi , F.M. Rouquette Jr","doi":"10.15232/aas.2023-02428","DOIUrl":"https://doi.org/10.15232/aas.2023-02428","url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to develop an age × BCS factor (ABC<sub>f</sub>) that could be used to estimate the ADG of stockers grazing bermudagrass (<em>Cynodon dactylon</em> [L.] Pers.) pasture as influenced by their age and BCS at the onset of stocking, hereafter referred to as the initial age and BCS.</p></div><div><h3>Materials and Methods</h3><p>Data on the ADG of stock- ers grazing bermudagrass in the southern United States were obtained from multiple sources, including literature, for various scenarios of initial age × BCS. Then, an ABC<sub>f</sub> for each age × BCS scenario was calculated by dividing its ADG by the ADG of calves 7 to 10 mo old with BCS of 5, a standard age × BCS scenario. Finally, an ABC<sub>f</sub> equa- tion was derived by regressing the ABC<sub>f</sub> values against the BCS values under each age group.</p></div><div><h3>Results and Discussion</h3><p>We derived the following ABC<sub>f</sub> equation to estimate the ADG of a stocker grazing bermudagrass pasture as ADG′ = ADG × ABC<sub>f</sub>, where and BCS on ADG of stockers grazing bermudagrass pas- ture. Current ADG indices or estimates do not account for the interacting effects of initial age and BCS. By incorpo- rating the ABC<sub>f</sub> into an ADG prediction system, the scien- tific community and stakeholders can more accurately as- sess the effects of these attributes on animal performance and develop appropriate purchase pricing and supplemen- tation strategies before and during stocking.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"39 6","pages":"Pages 371-379"},"PeriodicalIF":1.5,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286523000629/pdf?md5=588fdce55345326cfdb29d2d7f9f3776&pid=1-s2.0-S2590286523000629-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138465619","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}
W.Z. Yang , P.M.T. Lima , S. Ramirez , E. Schwandt , T.A. McAllister
Objective
This study examined the effects of a commercial phytogenic feed additive (PFA) on growth performance, feed efficiency, carcass traits, liver abscesses, and the immune response of growing and finishing steers.
Materials and Methods
Forty-five crossbred Angus steers (initial BW = 272 ± 20.5 kg) housed in individual pens (4.9 × 1.8 m) were used in a randomized complete block design in a 110-d growing and 120-d finishing experiment. Steers were blocked by BW and allocated to 1 of 3 treatments: control (without PFA and monensin), PFA at 500 mg/steer daily, or monensin at 300 mg/steer daily. Steers were fed a TMR ad libitum once daily and weighed on d 32, 59, and 110 in the growing phase but only at the beginning and the end of the finishing phase.
Results and Discussion
During growing, DMI did not differ, whereas final BW (trend; 415 vs. 403 kg) and ADG (numerically; 1.31 vs. 1.20 kg/d) were greater with PFA than control but did not differ from monensin (BW = 422 kg and ADG = 1.38 kg/d). Gain:feed was greater with monensin (0.173) than with PFA (0.161) and for the control (0.156). During finishing, ADG, G:F, and carcass traits did not differ, whereas DMI and acute proteins were lesser with monensin than with PFA and for the control.
Implications and Applications
Growing steers fed PFA had similar DMI and ADG but lesser G:F than did those given monensin. Both PFA and monensin resulted in similar growth performance and G:F in the finishing phase.
目的研究一种市产植物性饲料添加剂(PFA)对生长肥育肉牛生长性能、饲料效率、胴体性状、肝脓肿及免疫应答的影响。材料与方法选用45头安格斯杂交阉牛(初始体重= 272±20.5 kg)，饲养在4.9 × 1.8 m的单栏内，采用完全随机区组设计，进行生长110 d和肥育120 d试验。牛被体重阻断，并被分配到3个处理中的1个:对照组(不含PFA和莫能菌素)，PFA剂量为500毫克/头每天，或莫能菌素剂量为300毫克/头每天。每天1次自由饲喂TMR，生长期在第32、59和110天称重，肥育期只在开始和结束时称重。结果与讨论在生长过程中，DMI无显著差异;415 vs 403 kg)和日增重(数值;1.31 vs. 1.20 kg/d)，但与莫能菌素组(体重= 422 kg，平均日增重= 1.38 kg/d)差异不显著。增重:莫能菌素组(0.173)高于PFA组(0.161)和对照组(0.156)。在肥育期间，平均日增重、G:F和胴体性状无显著差异，而莫能菌素组的DMI和急性蛋白含量低于PFA组和对照组。与给予莫能菌素相比，饲喂PFA的生长公牛具有相似的DMI和ADG，但G:F较低。PFA和莫能菌素在肥育期的生长性能和G:F相似。
{"title":"Effects of a phytogenic feed additive on growth performance, feed intake, and carcass traits of beef steers","authors":"W.Z. Yang , P.M.T. Lima , S. Ramirez , E. Schwandt , T.A. McAllister","doi":"10.15232/aas.2023-02421","DOIUrl":"https://doi.org/10.15232/aas.2023-02421","url":null,"abstract":"<div><h3>Objective</h3><p>This study examined the effects of a commercial phytogenic feed additive (PFA) on growth performance, feed efficiency, carcass traits, liver abscesses, and the immune response of growing and finishing steers.</p></div><div><h3>Materials and Methods</h3><p>Forty-five crossbred Angus steers (initial BW = 272 ± 20.5 kg) housed in individual pens (4.9 × 1.8 m) were used in a randomized complete block design in a 110-d growing and 120-d finishing experiment. Steers were blocked by BW and allocated to 1 of 3 treatments: control (without PFA and monensin), PFA at 500 mg/steer daily, or monensin at 300 mg/steer daily. Steers were fed a TMR ad libitum once daily and weighed on d 32, 59, and 110 in the growing phase but only at the beginning and the end of the finishing phase.</p></div><div><h3>Results and Discussion</h3><p>During growing, DMI did not differ, whereas final BW (trend; 415 vs. 403 kg) and ADG (numerically; 1.31 vs. 1.20 kg/d) were greater with PFA than control but did not differ from monensin (BW = 422 kg and ADG = 1.38 kg/d). Gain:feed was greater with monensin (0.173) than with PFA (0.161) and for the control (0.156). During finishing, ADG, G:F, and carcass traits did not differ, whereas DMI and acute proteins were lesser with monensin than with PFA and for the control.</p></div><div><h3>Implications and Applications</h3><p>Growing steers fed PFA had similar DMI and ADG but lesser G:F than did those given monensin. Both PFA and monensin resulted in similar growth performance and G:F in the finishing phase.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"39 6","pages":"Pages 423-432"},"PeriodicalIF":1.5,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286523000678/pdf?md5=7c47d81c5b0c8e9e7f638a4c00ce8014&pid=1-s2.0-S2590286523000678-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138465625","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}
My objective was to provide a critical analysis of the major nutrition variables when feeding dairy calves and to provide practical applications.
Sources
Peer-reviewed scientific literature, research abstracts, and field experiences in dairy and calf ranch operations were used.
Synthesis
A variety of liquids are fed to dairy calves in the United States, and most often, they are fed in combinations. It is critical to know and measure composition and solids levels, and to ensure consistency in what liquid is fed and how it is fed. Avoid greater than 15% solids to minimize digestive upsets due to osmolality. Traditional early weaning programs and 20% CP/20% fat milk replacer (MR) have been replaced with higher CP MR and fed at higher levels resulting in more ADG prior to weaning. Given the inverse relationship between MR fed (and its fat level) and calf starter (CS) intake, the challenge then is to moderate MR feeding early enough prior to weaning to ensure adequate CS intake prior to weaning to optimize functional rumen development and minimize postweaning slump.
Conclusions and Applications
Feed a well-texturized CS to optimize functional rumen development and avoid needing to feed forage or roughage prior to weaning. Too much forage fed too soon impairs rumen development and confounds true BW gain with gut fill. Water is the most essential nutrient needed in the greatest quantity by dairy calves. It is consumed at about 4:1 relative to DMI. Ensure water and CS containers are physically separated to avoid contamination of each in the other and to have better intake and performance. In colder weather, feed warm water. Calves are most efficient in converting nutrients to growth on a dairy farm when properly fed and managed.
{"title":"PERSPECTIVE AND COMMENTARY: Dairy calf feeding and nutrition major variables and subsequent performance","authors":"A.F. Kertz, PAS","doi":"10.15232/aas.2023-02453","DOIUrl":"https://doi.org/10.15232/aas.2023-02453","url":null,"abstract":"<div><h3>Purpose</h3><p>My objective was to provide a critical analysis of the major nutrition variables when feeding dairy calves and to provide practical applications.</p></div><div><h3>Sources</h3><p>Peer-reviewed scientific literature, research abstracts, and field experiences in dairy and calf ranch operations were used.</p></div><div><h3>Synthesis</h3><p>A variety of liquids are fed to dairy calves in the United States, and most often, they are fed in combinations. It is critical to know and measure composition and solids levels, and to ensure consistency in what liquid is fed and how it is fed. Avoid greater than 15% solids to minimize digestive upsets due to osmolality. Traditional early weaning programs and 20% CP/20% fat milk replacer (MR) have been replaced with higher CP MR and fed at higher levels resulting in more ADG prior to weaning. Given the inverse relationship between MR fed (and its fat level) and calf starter (CS) intake, the challenge then is to moderate MR feeding early enough prior to weaning to ensure adequate CS intake prior to weaning to optimize functional rumen development and minimize postweaning slump.</p></div><div><h3>Conclusions and Applications</h3><p>Feed a well-texturized CS to optimize functional rumen development and avoid needing to feed forage or roughage prior to weaning. Too much forage fed too soon impairs rumen development and confounds true BW gain with gut fill. Water is the most essential nutrient needed in the greatest quantity by dairy calves. It is consumed at about 4:1 relative to DMI. Ensure water and CS containers are physically separated to avoid contamination of each in the other and to have better intake and performance. In colder weather, feed warm water. Calves are most efficient in converting nutrients to growth on a dairy farm when properly fed and managed.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"39 6","pages":"Pages 449-455"},"PeriodicalIF":1.5,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138466328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M.R. Beck , PAS, J.A. Proctor , Z. Kasuske , J.K. Smith , V.N. Gouvêa , C.L. Lockard , B. Min , D. Brauer
Objective
The objective of this experiment was to determine the effects of feeding malted barley (MB) as a source of exogenous α-amylase to finishing beef steers on growth performance and methane (CH4) emissions.
Materials and Methods
Forty crossbred yearling steers (initial BW = 522 ± 31.4 kg) were used in a randomized complete block design. Steers were blocked by BW and assigned to 1 of 2 pens, each containing an automated head chamber system (GreenFeed; C-Lock Inc., Rapid City, SD) and individual feed bunks with Calan gates (American Calan, Northwood, NH). Animals were then randomized to receive finishing diets formulated to be iso-nitrogenous and iso-energetic but contain (DM basis) either 0% MB (0MB), 10% MB (10MB), or 20% MB (20MB).
Results and Discussion
There was no effect of MB inclusion on DMI or ADG (P ≥ 0.20); however, there was a linear decrease (P ≤ 0.02) in feed efficiency and DM digestibility with increasing MB inclusion. Furthermore, MB inclusion resulted in a quadratic response (P = 0.05), where CH4 production (g of CH4/d) was increased by the MB diets. Increasing MB did not affect CH4 yield (P ≥ 0.13; g of CH4/kg of DMI), but there was a tendency for a linear increase in emission intensity (g of CH4/kg of ADG; P = 0.09).
Implications and Applications
We speculate that the decreased DM digestibility and feed efficiency were caused by the MB being fed unprocessed—highlighting the need for further research where MB is fed processed (e.g., dry rolled).
{"title":"Effects of replacing steam-flaked corn with increasing levels of malted barley in a finishing ration on feed intake, growth performance, and enteric methane emissions of beef steers","authors":"M.R. Beck , PAS, J.A. Proctor , Z. Kasuske , J.K. Smith , V.N. Gouvêa , C.L. Lockard , B. Min , D. Brauer","doi":"10.15232/aas.2023-02435","DOIUrl":"https://doi.org/10.15232/aas.2023-02435","url":null,"abstract":"<div><h3>Objective</h3><p>The objective of this experiment was to determine the effects of feeding malted barley (MB) as a source of exogenous α-amylase to finishing beef steers on growth performance and methane (CH<sub>4</sub>) emissions.</p></div><div><h3>Materials and Methods</h3><p>Forty crossbred yearling steers (initial BW = 522 ± 31.4 kg) were used in a randomized complete block design. Steers were blocked by BW and assigned to 1 of 2 pens, each containing an automated head chamber system (GreenFeed; C-Lock Inc., Rapid City, SD) and individual feed bunks with Calan gates (American Calan, Northwood, NH). Animals were then randomized to receive finishing diets formulated to be iso-nitrogenous and iso-energetic but contain (DM basis) either 0% MB (0MB), 10% MB (10MB), or 20% MB (20MB).</p></div><div><h3>Results and Discussion</h3><p>There was no effect of MB inclusion on DMI or ADG (<em>P</em> ≥ 0.20); however, there was a linear decrease (<em>P</em><span> ≤ 0.02) in feed efficiency and DM digestibility with increasing MB inclusion. Furthermore, MB inclusion resulted in a quadratic response (</span><em>P</em> = 0.05), where CH<sub>4</sub> production (g of CH<sub>4</sub>/d) was increased by the MB diets. Increasing MB did not affect CH<sub>4</sub> yield (<em>P</em> ≥ 0.13; g of CH<sub>4</sub>/kg of DMI), but there was a tendency for a linear increase in emission intensity (g of CH<sub>4</sub>/kg of ADG; <em>P</em> = 0.09).</p></div><div><h3>Implications and Applications</h3><p>We speculate that the decreased DM digestibility and feed efficiency were caused by the MB being fed unprocessed—highlighting the need for further research where MB is fed processed (e.g., dry rolled).</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"39 6","pages":"Pages 525-534"},"PeriodicalIF":1.5,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138466341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gary J. Vogel , William C. Kayser , Michael C. Savides , Matt Edmonds , Nick Van Engen , Tracye M. Edwards , Janet B. Allen , Phillip J. Rincker , Ty E. Lawrence , Floyd K. McKeith , Scott E. Roland , G. Allen Bridges , K.D. Miller , Cory T. Herr
Objective
Our objective was to evaluate tissue residue levels, calculated NH3 gas emissions and live and carcass growth in finishing beef steers fed lubabegron (LB).
Materials and Methods
In Exp 1, 50 steers were fed ad libitum a diet containing LB at 1.54 or 5.53 mg/kg of DM for 14 d, followed by a voluntary removal duration of 0, 1, 2, 4, 6, or 8 d before slaughter. Nongastrointestinal tract (GI) tissues collected and analyzed were muscle, liver, tongue, heart, bone, bone marrow, and tendon. In Exp 2, 700 steers were supplemented with either a diet containing LB at 3.5 mg/kg of DM or a negative control for 56 d. Supplementation was followed by removal durations of 0, 2, 4, 6, 8, and 16 d before slaughter. At slaughter, a subset of steers (35; 5 per treatment) were selected to sample GI and non-GI tissues for LB residues, and the remaining animals were used to evaluate the live and carcass growth.
Results and Discussion
In Exp 1, all non-GI tract tissues were below the 3 μg/kg limit of quantification (LOQ), except for the tongue. At the greater supplementation level (5.53 mg/kg) tongue had residues of 3.80 and 2.08 μg/kg for removal durations 0 and 1 d, respectively. Within GI tissues, steers supplemented with the lower dose (1.54 mg/kg) had detectable residues within the reticulum (0–2 d), rumen (0–1 d), omasum (0–4 d), and abomasum (0–2 d). Steers supplemented with the higher dose (5.53 mg/kg), had detectable residues within the reticulum (0–4 d), rumen (0–2 d), omasum (0–6 d), small intestine (0–1d), and large intestine (0 d). In Exp 2, the LOQ for LB residues was 1 μg/kg, and residues were detectable in liver (0 d), muscle (0–2 d), rumen (0–4 d), reticulum (0–4 d), and omasum (0–16 d). Steers supplemented with LB had greater final BW (P < 0.001), ADG (P < 0.001), G:F (P< 0.001), hot carcass weight (P < 0.001), DP (P < 0.001), and rib-eye area (P < 0.001) than the negative control. Furthermore, steers fed LB exhibited reduced marbling score (P < 0.001) and YG (P < 0.001) compared with control steers. Calculated NH3 gas emissions were greater (P< 0.001) for control steers (6,204 g/head) compared with LB-supplemented steers (5,202 to 5,348 g/head).
Conclusions and Application
These results demonstrate that LB residue concentrations are affected by supplementation concentrations, tissue type, and duration of removal before slaughter. Furthermore, the LB supplementation results in greater red meat yield and decreased calculated NH3 gas emissions.
{"title":"Effects of lubabegron removal on tissue concentration, calculated ammonia gas emissions, live performance, and carcass characteristics of beef steers","authors":"Gary J. Vogel , William C. Kayser , Michael C. Savides , Matt Edmonds , Nick Van Engen , Tracye M. Edwards , Janet B. Allen , Phillip J. Rincker , Ty E. Lawrence , Floyd K. McKeith , Scott E. Roland , G. Allen Bridges , K.D. Miller , Cory T. Herr","doi":"10.15232/aas.2023-02442","DOIUrl":"https://doi.org/10.15232/aas.2023-02442","url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to evaluate tissue residue levels, calculated NH<sub>3</sub> gas emissions and live and carcass growth in finishing beef steers fed lubabegron (LB).</p></div><div><h3>Materials and Methods</h3><p>In Exp 1, 50 steers were fed ad libitum a diet containing LB at 1.54 or 5.53 mg/kg of DM for 14 d, followed by a voluntary removal duration of 0, 1, 2, 4, 6, or 8 d before slaughter. Nongastrointestinal tract (GI) tissues collected and analyzed were muscle, liver, tongue, heart, bone, bone marrow, and tendon. In Exp 2, 700 steers were supplemented with either a diet containing LB at 3.5 mg/kg of DM or a negative control for 56 d. Supplementation was followed by removal durations of 0, 2, 4, 6, 8, and 16 d before slaughter. At slaughter, a subset of steers (35; 5 per treatment) were selected to sample GI and non-GI tissues for LB residues, and the remaining animals were used to evaluate the live and carcass growth.</p></div><div><h3>Results and Discussion</h3><p>In Exp 1, all non-GI tract tissues were below the 3 μg/kg limit of quantification (LOQ), except for the tongue. At the greater supplementation level (5.53 mg/kg) tongue had residues of 3.80 and 2.08 μg/kg for removal durations 0 and 1 d, respectively. Within GI tissues, steers supplemented with the lower dose (1.54 mg/kg) had detectable residues within the reticulum (0–2 d), rumen (0–1 d), omasum (0–4 d), and abomasum (0–2 d). Steers supplemented with the higher dose (5.53 mg/kg), had detectable residues within the reticulum (0–4 d), rumen (0–2 d), omasum (0–6 d), small intestine (0–1d), and large intestine (0 d). In Exp 2, the LOQ for LB residues was 1 μg/kg, and residues were detectable in liver (0 d), muscle (0–2 d), rumen (0–4 d), reticulum (0–4 d), and omasum (0–16 d). Steers supplemented with LB had greater final BW (<em>P</em> < 0.001), ADG (<em>P</em> < 0.001), G:F (<em>P</em>< 0.001), hot carcass weight (<em>P</em> < 0.001), DP (<em>P</em> < 0.001), and rib-eye area (<em>P</em> < 0.001) than the negative control. Furthermore, steers fed LB exhibited reduced marbling score (<em>P</em> < 0.001) and YG (<em>P</em> < 0.001) compared with control steers. Calculated NH<sub>3</sub> gas emissions were greater (<em>P</em>< 0.001) for control steers (6,204 g/head) compared with LB-supplemented steers (5,202 to 5,348 g/head).</p></div><div><h3>Conclusions and Application</h3><p>These results demonstrate that LB residue concentrations are affected by supplementation concentrations, tissue type, and duration of removal before slaughter. Furthermore, the LB supplementation results in greater red meat yield and decreased calculated NH<sub>3</sub> gas emissions.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"39 6","pages":"Pages 484-493"},"PeriodicalIF":1.5,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286523000733/pdf?md5=184049bab5f49536e1f38350799fb59f&pid=1-s2.0-S2590286523000733-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138466331","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号