Publications (129)160.03 Total impact
- [Show abstract] [Hide abstract] ABSTRACT: Crossbred yearling steers ( = 360; 395 ± 33.1 kg initial BW) were used to evaluate the effects of dry-rolled corn (DRC) particle size in diets containing 20% wet distiller's grains plus solubles on feedlot performance, carcass characteristics, and starch digestibility. Steers were used in a randomized complete block design and allocated to 36 pens (9 pens/treatment, with 10 animals/pen). Treatments were coarse DRC (4,882 μm), medium DRC (3,760 μm), fine DRC (2,359 μm), and steam-flaked corn (0.35 kg/L; SFC). Final BW and ADG were not affected by treatment ( > 0.05). Dry matter intake was greater and G:F was lower ( < 0.05) for steers fed DRC vs. steers fed SFC. There was a linear decrease ( < 0.05) in DMI in the final 5 wk on feed with decreasing DRC particle size. Fecal starch decreased (linear, < 0.01) as DRC particle size decreased. In situ starch disappearance was lower for DRC vs. SFC ( < 0.05) and linearly increased ( < 0.05) with decreasing particle size at 8 and 24 h. Reducing DRC particle size did not influence growth performance but increased starch digestion and influenced DMI of cattle on finishing diets. No differences ( > 0.10) were observed among treatments for any of the carcass traits measured. Results indicate improved ruminal starch digestibility, reduced fecal starch concentration, and reduced DMI with decreasing DRC particle size in feedlot diets containing 20% wet distiller's grains on a DM basis.
- [Show abstract] [Hide abstract] ABSTRACT: A total of 442 Angus and crossbred steers (initial BW = 243 ± 13.1 kg) were used in a randomized complete block design to evaluate the effect of implant timing on performance and health of newly received steers. Treatments included administration of a growth implant (Revalor-XS; Merck Animal Health, Summit, NJ) on d 0 of the experiment (ARR) or d 28 (DEL). On d 0, 5 steers from each pen were injected with ovalbumin (OVA) to evaluate a primary humoral immune response. On d 28, the same 5 steers received a secondary OVA injection, and 5 additional steers from each pen received a single OVA injection. Final BW (P = 0.02) and ADG d 0 through slaughter (P = 0.03) were greater for DEL compared with ARR (BW: 636 vs. 627 ± 8.3 kg; ADG: 1.78 vs. 1.74 kg ± 0.029, respectively). Steers implanted on arrival had greater DMI (P < 0.02) d 0 to 28, d 29 to 56, and d 57 to 112 and lower (P < 0.03) G:F d 57 to 112, d 113 to 169, d 170 to slaughter, and d 0 to slaughter (0.175 vs. 0.186 ± 0.003) when compared with DEL steers. On a pen mean basis, BW at d 28 and ADG d 0 to 28 were numerically higher (P = 0.25) for ARR steers as compared with DEL steers (294 vs. 291 ± 1.8 kg and 1.80 vs. 1.71 ± 0.061 kg, respectively). Hot carcass weight was numerically greater (P = 0.16) for DEL compared with ARR steers (383 vs. 378 ± 3.6 kg, respectively). Steers implanted on arrival tended (P < 0.07) to have greater OVA IgG concentration after OVA administration. These results suggest that delaying the time of growth implant administration of newly received cattle had minimal effects on animal performance, health, and, immune response. The observed improvements in feedlot performance from d 0 through slaughter that were observed for the DEL versus ARR steers were likely due to timing of slaughter relative to depletion of implant active ingredients.
- [Show abstract] [Hide abstract] ABSTRACT: Sensory analysis of ground LL samples representing 12 beef product categories was conducted in 3 different regions of the U.S. to identify flavor preferences of beef consumers. Treatments characterized production-related flavor differences associated with USDA grade, cattle type, finishing diet, growth enhancement, and postmortem aging method. Consumers (N=307) rated cooked samples for 12 flavors and overall flavor desirability. Samples were analyzed to determine fatty acid content. Volatile compounds produced by cooking were extracted and quantified. Overall, consumers preferred beef that rated high for beefy/brothy, buttery/beef fat, and sweet flavors and disliked beef with fishy, livery, gamey, and sour flavors. Flavor attributes of samples higher in intramuscular fat with greater amounts of monounsaturated fatty acids and lesser proportions of saturated, odd-chain, omega-3, and trans fatty acids were preferred by consumers. Of the volatiles identified, diacetyl and acetoin were most closely correlated with desirable ratings for overall flavor and dimethyl sulfide was associated with an undesirable sour flavor.
- [Show abstract] [Hide abstract] ABSTRACT: Nutrient apparent digestibility, intake, performance, microbial efficiency, and energy and protein requirements for growing Nellore heifers and steers were evaluated, fifty animals were used, 32 Nellore heifers and 18 Nellore steers. Four animals of each gender used as baseline reference animals were slaughtered at the beginning of the experiment. Four animals from each gender were fed at MAIN receiving 11 g/kg BW, whereas 10 steers and 24 heifers were assigned to the ADLIB group. The ADLIB heifers were divided further into 4 groups according to the dietary treatment: 1) Ca and P fed at their proposed requirements (CaPR) with a 50:50 roughage:concentrate (R:C) diet, 2) CaPR with a 70:30 R:C diet, 3) 43% of their proposed requirements for Ca and 80% of their requirements for P (CaPL) with a 50:50 R:C diet, and 4) CaPL with a 70:30 R:C diet. The ADLIB and MAIN steers were fed CaPR with a 50:50 R:C diet. Half of the ADLIB steers and heifers were slaughtered at d 50; the other ADLIB animals were slaughtered after 100 days of the feeding period, whereas all MAIN animals were slaughtered at d 100. Total feces and urine were collected from all animals for 72 h prior to slaughter. After slaughter, EBW was measured. The NEm and MEm requirements were estimated by exponentially relating heat production with metabolizable energy intake; NEg was estimated from EBW and EBG. The NPg was estimated from EBG and RE. Dry matter digestibility and the apparent absorption and retention of Ca and P were similar across Ca and P treatments. Final body weight, and consequently ADG, was greater (P<0.05) for heifers receiving the high concentrate compared to the low concentrate diet, but dietary Ca and P concentration did not affect (P>0.05) performance. The NEm and MEm requirements were 294 and 496 kJ/kg EBW0.75, respectively. Net protein for maintenance was 1.28 g/kg BW0.75 and NEg and NPg were estimated from the following equations: NEg=0.222×EBW0.75×EBG0.6263 and NPg=137.53×EBG – 0.038×RE, respectively. Under the conditions of this experiment, reducing the dietary concentrations of Ca and P had no significant impact on intake, digestibility, or performance of growing Nellore heifers and steers.
- [Show abstract] [Hide abstract] ABSTRACT: A total of 360 steers (initial BW = 350 kg, SD = 28.1 kg) were used in a randomized complete-block-design experiment to determine the effects of trace mineral concentration and source on feedlot performance, carcass characteristics, liver trace mineral status, and diet in vitro solubility of Cu and Zn. Target treatments consisted of (1) basal diet; (2) basal diet supplemented with 10 mg of Cu from CuSO4, 30 mg of Zn from ZnSO4, 20 mg of Mn from MnSO4, 0.50 mg of I from ethylenediamine dihydriodide, 0.10 mg of Se from Na2O3Se, and 0.10 mg of Co from CoCO3 per kilogram of DM (NRC); (3) basal diet supplemented with the same sources of Cu, Zn, Mn, I, Se, and Co as treatment 2 but provided at 20, 100, 50, 0.50, 0.20, and 0.20 mg of mineral/kg of DM, respectively (CNI); and (4) basal diet supplemented with 66.6% inorganic and 33.4% organic Cu, Zn, and Mn and inorganic forms of Co, I, and Se at iso-concentrations to treatment 3 (CNO). No differences (P > 0.10) between treatments for feedlot performance; final liver Zn, Mn, Se, and Co concentrations; and carcass merit were observed. In vitro procedures were used to examine the solubility of Cu and Zn from the diets used for the feeding experiment. Dry matter disappearance was similar across treatments (P > 0.10). Percentage of Cu and Zn solubilized after simulated rumen and abomasal digestion was less (P < 0.05) for the basal diet compared with NRC, CNI, and CNO diets and NRC compared with CNI and CNO diets. Under the conditions of this experiment, it appears that basal dietary concentrations of trace mineral were adequate for growth and performance of finishing yearling feedlot steers.
- [Show abstract] [Hide abstract] ABSTRACT: Beef nutrition research has become increasingly important domestically and internationally for the beef industry and its consumers. The objective of this study was to analyze the nutrient composition of ten beef loin and round cuts to update the nutrient data in the USDA National Nutrient Database for Standard Reference. Seventy-two carcasses representing a national composite of Yield Grade, Quality Grade, sex classification, and genetic type were identified from six regions across the U.S. Beef short loins, strip loins, tenderloins, inside rounds, and eye of rounds (NAMP # 173, 175, 190A, 169A, and 171C) were collected from the selected carcasses and shipped to three university meat laboratories for storage, retail fabrication, and raw/cooked analysis of nutrients. Sample homogenates from each animal were analyzed for proximate composition. These data provide updated information regarding the nutrient status of beef, in addition, to determining the influence of Quality Grade, Yield Grade, and sex classification on nutrient composition. Copyright © 2015. Published by Elsevier Ltd.
- [Show abstract] [Hide abstract] ABSTRACT: This study investigated the influence of day of gestation (DG) and feeding regimens (FR) on the expression of genes responsible for placenta development, nutrient transfer, and angiogenic factors in Holstein × Gyr cows. Forty pregnant multiparous Holstein × Gyr cows with an average initial body weight of 482 ± 10.8 kg and an initial age of 5 ± 0.8 yr were allocated to 1 of 2 FR: ad libitum (AL; n = 20) or maintenance level (ML; n = 20). Maintenance level was considered to be 1.15% of body weight (dry matter basis) and met 100% of the net energy requirements and AL provided 190% of the total net energy requirements. Cows were slaughtered at 4 DG: 139, 199, 241, and 268 d. After the cows were slaughtered, the placenta and uterus were separated and weighed. Caruncles and cotyledons were individually separated, counted, and weighed. Placenta expressed as kilograms and grams per kilogram of empty body weight (EBW) was heavier in ML- than in AL-fed cows at 268 d of gestation. Placenta expressed as kilograms and grams per kilogram of EBW was the lightest at 139 d of gestation, and the greatest mass was observed at 268 d in ML-fed cows. However, in AL-fed cows, the heaviest placenta expressed as grams per kilogram of EBW was observed from 199 d of gestation. Placentomes expressed as grams per kilogram of EBW were heavier in ML-fed cows during gestation, and the number of placentomes was greater in ML-fed cows at 268 d of gestation. We observed that IGFR1 and IGFR2 were involved in placenta adaptations when ML was provided, as their expression in placentome cells was greater in ML-fed cows at 268 d of gestation. The genes responsible for angiogenesis were also greater in ML-fed cows: VEGFA, GUCY1B3, HIFA, FGF2, and NOS3 were altered by FR and DG interaction and they were greater in ML-fed cows at 268 d of gestation. In addition, VEGFB and ANGPT2 did not show interactions between FR and DG, but they were greater in ML-fed cows. Thus, we suggest that the placenta from an ML-fed cow develops adaptations to the reduced nutrient supply by altering its structure and gene expression, thereby developing mechanisms for potential increased nutrient transfer efficiency to the fetus. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
- [Show abstract] [Hide abstract] ABSTRACT: This study investigated how feeding regimen (FR) alters apparent total-tract digestibility, performance, N balance, excretion of purine derivatives, and fat deposition in Holstein × Gyr cows at different days of gestation (DG). Forty-four pregnant multiparous Holstein × Gyr cows with an average initial body weight of 480 ± 10.1 kg and an initial age of 5 ± 0.5 yr old were allocated to 1 of 2 FR: ad libitum (AL; n = 20) and maintenance level (ML; n = 24). Maintenance level was considered to be 1.15% of body weight on a dry matter (DM) basis and met 100% of the energy requirements, whereas AL provided 190% of total net energy requirements. Data for hot and cold carcass dressing, fat deposition, average daily gain, empty body gain, and average daily gain without the gravid uterus were analyzed as a 4 × 2 factorial design. Intake, apparent total-tract digestibility, N balance, urinary concentration of urea, and purine derivatives data were analyzed as repeated measurements taken over the 28-d period (122, 150, 178, 206, 234, and 262 d of gestation). Cows were individually fed a corn silage-concentrate based diet composed of 93% roughage and 7% concentrate (DM basis) as a total mixed ration. Pregnant cows were slaughtered on 4 different DG: 139 (n = 11), 199 (n = 11), 241 (n = 11), and 268 d (n = 11). Overall, DM intake decreased as DG increased. This decrease observed in DM intake may be associated with the reduction in ruminal volume caused by the rapid increase in fetal size during late gestation. We observed an interaction for DM and organic matter apparent total-tract digestibility between FR and DG; at 150, 178, and 206 d of gestation, ML-fed cows had greater DM and organic matter apparent total-tract digestibility values than AL-fed cows. Rib fat thickness, mesentery, and kidney, pelvic, and heart fat were greater in AL-fed than in ML-fed cows at all DG, with the exception of rib fat thickness on d 139. Ad libitum-fed cows excreted more N in their feces and urine compared with ML-fed cows. Pregnant cows that were fed at maintenance had greater digestibility during some DG, excreted less N in feces and less N and urea in urine, and deposited less fat in the body. We therefore recommend ML (1.15% of body weight with 93% of roughage) as a FR for pregnant dry cows; however, during the last month of gestation, AL seems to be the most appropriate FR to avoid loss of body weight. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
- [Show abstract] [Hide abstract] ABSTRACT: This study investigated the influence of day of gestation (DG) and feeding regimens (FR) on maternal and fetal visceral organ mass in Holstein × Gyr cows. Forty-four pregnant multiparous Holstein × Gyr cows with an average initial body weight of 480 ± 10.1 kg and an average initial age of 5 ± 0.5 yr were allocated to 1 of 2 FR: ad libitum (AL; n = 20) or maintenance level (ML; n = 24). Maintenance level was considered to be 1.15% of body weight (dry matter basis) and met 100% of the energy requirements; AL provided 190% of the total net energy requirements. Cows were individually fed a corn silage and concentrate-based diet composed of 93% roughage and 7% concentrate (dry matter basis) as a total mixed ration twice daily. Pregnant cows were slaughtered at 4 DG: 139 (n = 11), 199 (n = 11), 241 (n = 11), and 268 (n = 11) d, which was followed by necropsy. Mass of heart, liver, and gastrointestinal tract was heavier in AL- than in ML-fed cows. Mammary gland mass was heavier in AL- than in ML-fed cows, and the heaviest mass was observed at 268 d of gestation. Feeding regimen did not influence fetal body weight in this study. The majority of the visceral organ masses were similar in fetuses from cows fed AL or ML. These data indicate that maternal feed restriction does not affect the development of most fetal organs or fetal development; however, some maternal organs are affected by the FR provided. Moreover, the negative effect on mammary gland mass caused by ML feeding will probably not affect the subsequent lactation because the crude protein concentration in the mammary gland increased with ML feeding. However, we suggest that the AL diet in pregnant dry cows should be provided with caution because the amount of fat in the mammary gland increased at 268 d of gestation. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
- [Show abstract] [Hide abstract] ABSTRACT: To investigate the impact of duration of maternal undernutrition in twin sheep pregnancies, ewes were either fed 100% (C), or 50% of their nutrient requirements from 28 to 78 d gestational age (dGA) and readjusted to 100% beginning at 79 dGA (LC), or continuously restricted from 28 to 135 dGA (LL). Weights of the fetus, empty carcass, brain, and liver were greater in the LC than LL fetuses at 135 dGA (P ≤ 0.05). While umbilical vein (UmV) glucose concentrations did not differ, the UmV:umbilical artery (UmA) glucose gradient was smaller (0.26 ± 0.03 vs 0.38 ± 0.03 and 0.39 ± 0.04 mmol L-1; P ≤ 0.05) in LL than C and LC fetuses, respectively. Umbilical vein concentrations of IGF-1 were less (46.7 ± 5.62 vs 74.3 ± 6.71 ng/ml; P ≤ 0.05) in LL than LC fetuses. Additionally, LL fetuses tended (P ≤ 0.10) to have lower UmA concentrations of insulin (0.24 ± 0.13 vs 0.70 ± 0.15 ng/ml) and IGF-1 (66.6 ± 7.51 vs 91.4 ± 8.97 ng/ml) than LC fetuses. While most of the observed differences occurred between LC and LL pregnancies, LC fetuses tended (P ≤ 0.10) to have greater UmV and UmA pCO2 than C fetuses. Furthermore, the UmV:UmA O2 content gradient tended to be greater (5.02 ± 0.43 vs 3.41 ± 0.47; P ≤ 0.10) in C than LL fetuses. UmA placental lactogen also tended to be greater (46.6 ± 4.40 vs 31.1 ± 4.69 ng/ml; P ≤ 0.10) in LL than C fetuses. These data suggest that in twin pregnancies, maternal undernutrition followed by realimentation induces a different fetal outcome compared with continuous nutrient restriction, and both may differ physiologically from control fed pregnancies.
- [Show abstract] [Hide abstract] ABSTRACT: The present experiment was designed to evaluate the use of microbial markers (MM), sampling sites (SS), and marker systems (MS) to estimate microbial nitrogen (MN) synthesis in bulls and to develop equations to correct MN estimates when only one of the aforementioned techniques was utilized. The MM systems evaluated were 1) purine bases (PB) and 2) 15N labeling. The SS evaluated were: 1) reticulum, 2) omasum, and 3) abomasum, and the single, double and triple MS were evaluated. Eight crossbred (Holstein×Zebu) bulls (353±36.9 kg of BW; 24±1 mo) with ruminal and abomasal cannulas were utilized in this experiment. The following experimental diets were used: 1) 60% corn silage+40% concentrate, 2) 40% corn silage+60% concentrate, 3) 60% fresh sugarcane+40% concentrate, and 4) 40% fresh sugarcane+60% concentrate. Four experimental periods lasting 16 d each were completed with 10 d for adaptation to the experimental diet and 6 d for sampling. Bulls were randomly distributed into two 4×4 Latin squares balanced for residual effects. Data were analyzed in a Latin square design using PROC MIXED. Interactions were observed (P<0.05) in MN, microbial crude protein/total digestible nutrients (MCP/TDN), microbial nitrogen/rumen fermented organic matter (MN/RFOM), microbial nitrogen/rumen truly fermented organic matter (MN/RTFOM), and microbial dry matter/rumen fermented total carbohydrates (MDM/RFTCHO) between SS and MM. For PB, the greatest (P<0.01) values of MN were observed for the digesta sampled in the reticulum and abomasum. In contrast, for 15N, the greatest (P<0.01) values were observed for digesta sampled in the omasum and abomasum. Microbial nitrogen yield was only different (P<0.05) when using reticulum and 15N from those estimated using abomasum and 15N. Thus, the equation developed to correct MN value was: MN (g/d)=27.93±2.46+0.99±0.09×reticulum 15N. The triple MS exhibited the greatest (P<0.01) value of MN compared to the single and double MS. No interactions (P>0.05) were observed between MS and MM or SS; thus, the equation established to correct MN value used only the MS. In conclusion, we have demonstrated that there is no difference using 15N to estimate MN yield if omasum or abomasum are used. Therefore, the omasum can be used as an accurate SS to predict MN. The triple MS presented higher values than the single and double MS. Thus, if single or double MS is used the value must be corrected by the equation obtained using the triple MS.
- [Show abstract] [Hide abstract] ABSTRACT: To determine if supplementation of omega (ώ)-3 long chain polyunsaturated fatty acid (LCPUFA) alters synovial fluid fatty acid composition and prostaglandin E2 (PGE2) concentration of mature, healthy horses.: Twenty, non-pregnant light breed mares were assigned into one of three daily dietary treatments. Group 1 (MARINE) received 38g total of the ώ-3 LCPUFA alpha linolenic acid (ALA, 2g), eicosapentaenoic acid (EPA, 7.6g) and docosahexaenoic acid (DHA, 26.6g) via a marine-derived supplement; Group 2 (FLAX) received 38g of ώ-3 ALA via a flaxseed supplement and Group 3 (CONT) did not receive additional ώ-3 LCPUFA. Blood was taken at baseline, 30, 60, and 90 days of supplementation and plasma separated. After of 90 days of supplementation, 3 ml of synovial fluid was obtained through arthrocentesis. Plasma and synovial fluid were analyzed to identify fatty acid profiles, and determine PGE2 concentration. MARINE synovial fluid fatty acids contained higher of EPA and DHA compared to the CONT group; and higher DHA levels compared to FLAX group. EPA was not detected in synovial fluid from the FLAX group. Prostaglandin E2 did not differ (P>0.05) among horses; however, the MARINE group tended (P=0.10) to have lower synovial PGE2 concentration compared to CONT horses. The presence of EPA and DHA only in MARINE synovial fluid and plasma suggests direct supplementation of EPA and DHA is needed to modify fatty acid composition. A tendency for lower synovial PGE2 in healthy horses receiving oral EPA/DHA merits further investigation in the ώ-3 supplementation effect on prostaglandin production.
- [Show abstract] [Hide abstract] ABSTRACT: The objective of this study was to evaluate the influence of corn silage (CS) or sugar cane (SC) additions to finishing diets on voluntary intake, apparent digestibility, animal performance, and LM fatty acid (FA) composition in crossbred Holstein × Zebu bulls. Forty-two bulls (initial BW 328 ± 39.2 kg and an initial age of 23.5 mo) were utilized in this experiment. A completely randomized design was used to examine roughage source (CS vs. SC) and ratio of concentrate (CO) on nutrient utilization and production. The experimental diets consisted of: 1) 60% CS:40% CO fed for 84 d (CS 60:40), 2) 60% CS:40% CO fed for 42 d and 40% CS:60% CO fed for 42 d - CS reverse diet (CSR), 3) 40% CS:60% CO fed for 84 d (CS 40:60), 4) 60% SC:40% CO fed for 84 d (SC 60:40), 5) 60% SC:40% CO fed for 42 d and 40% SC:60% CO fed for 42 d - SC reverse diet (SCR), and 6) 40% SC:60% CO fed for 84 d (SC 40:60). Dry matter and NDF intakes were greater (P < 0.01) in bulls fed CS-based diets than bulls fed SC-based diets. The greatest (P < 0.01) DM and CP digestibility were observed in bulls fed SC-based diets. Bulls fed CSR and CS 40:60 had greater (P < 0.01) ADG than bulls fed SC-based diets. However, ADG was similar (P = 0.52) in bulls fed CS 60:40, CSR, and SC 40:60 diets. The percentage of C18:3(n-3) and C20:5(n-3) were greater (P < 0.01) in LM of bulls fed SC-based diets. The percentage of CLA was greater (P < 0.01) in LM of bulls fed SC 60:40 than those fed CS-based diets. The findings of the present study indicate that SC 40:60 can replace CS 60:40 and CSR in finishing diets and moreover, roughage source significantly altered the FA composition of crossbred Holstein × Zebu bulls LM.
- [Show abstract] [Hide abstract] ABSTRACT: A total of 432 crossbred yearling steers (329 ± 10.5 kg) were used in an unbalanced randomized block design to examine the effects of a medicinal feed additive (MFA) program and dietary sulfur (S) concentrations on feedlot performance and carcass merit. Treatments were arranged in a 2 × 2 factorial, with main factors being ionophore and antibiotic combination consisting of feed additive program monensin/tylosin or laidlomycin propionate/chlortetracycline and dietary S concentration [constant (CST) or variable (VAR)]. High-S diets (0.60% S) were fed on randomly assigned days to the VAR treatment, with low-S diets (0.48% S) fed on remaining days and to the CST treatment throughout the experiment. No interactions between S and MFA treatment were apparent for feedlot performance. Steers receiving VAR had greater (P < 0.05) BW than did CST-supplemented steers. Overall, DMI was greater (P < 0.05) for VAR than for the CST steers. Average daily gain and feed efficiency did not differ between CST and VAR. Steers receiving VAR diets had a mortality rate attributable to polioencephalomalacia 7.8 times greater (P < 0.02) than that of steers fed CST diets. Feedlot performance and carcass merit did not differ between the MFA treatments, and S treatment did not affect most carcass variables. The S × MFA interaction was significant (P < 0.05) for DP, such that S treatment had no effect on DP when monensin/tylosin was fed, but when steers were fed laidlomycin propionate/chlortetracycline, DP was decreased by 0.72% (P < 0.02) when VAR diets were fed. These results suggest that under our conditions, performance and carcass characteristics were not affected by MFA treatment. Furthermore, varying S concentration in finishing diets increased mortality rate; however, feedlot performance and carcass measurements were generally not affected by S treatment.
- [Show abstract] [Hide abstract] ABSTRACT: Forty-eight steer calves (initial BW = 314 ± 21 kg), housed on pasture with their dams, were used to document changes in growth performance and various physiological measures when fitted with (YD) or without (ND) an antisuckling device for 7 d and weaned (d 0) by fenceline (FS) or total separation (TS). All steers were weighed and bled on d − 7, − 4, 0, 3, 7, 14, and 35. On d 7 the FS group was moved to a pasture lot distant from their dams and adjoining the TS group. Weight gain was similar (P = 0.74) between ND and YD steers between d − 7 and 0. The YD-FS steers lost weight (P = 0.01) by d 3 compared with the YD-TS steers, and from d 14 to 35 the YD-TS steers were heavier (P = 0.02) than the YD-FS steers. Hematocrit (HCT) increased (P = 0.04) in YD but not ND steers by d − 4 and was similar between treatments thereafter. Before weaning, treatment had no effect on neutrophil-to-lymphocyte ratio, plasma cortisol, haptoglobin, ceruloplasmin, or serum interferon-γ (IFN-γ) concentrations. Plasma haptoglobin and ceruloplasmin increased (P < 0.01) in all steers from d − 7 to − 4. Upon weaning, d 3 ceruloplasmin was greater (P < 0.05) in FS vs. TS steers, d 7 plasma cortisol was greater (P < 0.05) in YD-FS vs. YD-TS steers, and d 14 IFN-γ was greater (P < 0.05) in TS vs. FS steers. Lymphocyte percentage tended (P < 0.10) to be lower for YD vs. ND steers on d 0 to 7 regardless of method of separation, resulting in an overall greater (P < 0.05) mean neutrophil-to-lymphocyte ratio for the YD steers. Use of a preweaning anti-suckling device marginally altered growth performance and physiology in beef steers postweaning.
- [Show abstract] [Hide abstract] ABSTRACT: The objectives of this study were to evaluate the effects of castration method (banding vs. surgical) and use of analgesia on behavior and feedlot performance in cull bulls. Angus, Hereford, and Angus-crossbred bulls (n = 20; initial BW = 384 ± 59.3 kg; 336 ± 20.1 d old) were housed in feedlot pens equipped with the ability to measure individual daily feed intake. A balanced randomized block design using a 2 × 2 factorial arrangement of treatments was utilized. A multimodal analgesia protocol (MMA) was used and consisted of s.c. ketamine-stun containing butorphanol (0.01 mg/kg BW), xylazine (0.02 mg/kg BW), ketamine (0.04 mg/kg BW), and a local 2% lidocaine hydrochloride anesthetic block of the spermatic cords (10 mL/cord) and scrotum (10 mL) on d 0. Flunixin meglumine (1.2 mg/kg) was administered i.v. on d 0, 1, 2 and 3 to MMA cattle. Cattle were stratified to treatments based on breed, BW, age, and a temperament score. Treatments included: 1) band castration without analgesia (BND); 2) band castration with analgesia (BND-MMA); 3) surgical castration without analgesia (SURG); and 4) surgical castration with analgesia (SURG-MMA). All castrations were performed on d 0. Chute exit velocity (EV) and time in chute (TIC) were collected on d -9, 0, 1, 2, and 13. Willingness-to-enter-chute (WTE) score, rectal temperature (TEMP), heart rate (HR), and respiration (RESP) were collected on d 0, 1, 2, 3, and 13. Cattle were weighed on d -9 and 13 while feeding behaviors were collected continuously for 57 d pre-castration and 28 d post-castration. There was a tendency (P < 0.09) for ADG to be greater in cattle receiving analgesia. Both SURG treatments exhibited elevated TEMP on d 1 (P < 0.001) and 2 (P < 0.05) compared to BND treatments. Post-castration DMI was greater (P = 0.02) in MMA treatments compared with non-medicated treatments throughout the trial. Meal duration was greater (P < 0.05) in BND than SURG castrates during the first week post-castration. Results suggest that pain mitigation reduces the impact of castration on ADG and DMI.
- [Show abstract] [Hide abstract] ABSTRACT: Two experiments evaluated the effects of band castration and oral administration of an analgesic in association with castration on performance and behavioral and physiological responses in yearling beef bulls. In Exp. 1 Angus and Charolais-crossbred bull calves (n = 127; 309.8 ± 59.04 kg) and in Exp. 2 Hereford, Angus, and Hereford × Angus crossbred bulls (n = 30; 300.8 ± 4.96 kg), were stratified by BW and randomly assigned to 1 of 3 treatments: 1) band castration (BAND), 2) band castration with oral administration of meloxicam (BAND-MEL), and 3) sham castration (SHAM). The BAND and SHAM procedures were completed on d 0. The SHAM treatment consisted of all animal manipulations associated with band castration without band application. Meloxicam was administered on d -1, 0, and 1 (1.0 mg/kg, 0.5 mg/kg and 0.5 mg/kg, respectively) via an oral bolus. Body weight and a subjective chute score (CS) were collected on d -1, 0, 1, 7, 14, and 21 (d 28 Exp. 1 only). In Exp. 2, jugular blood samples were collected immediately before castration and 24 hr post-castration for Substance P (SP) analysis. In Exp. 2, video documentation on d 0 was used to determine range of vertical head motion (DIST) on a subset of animals during treatment administration. In both experiments, ADG was similar (P ≥ 0.50) between BAND and BAND-MEL, but ADG in SHAM cattle was greater (P < 0.001) and tended (P = 0.07) to be greater than castrates in Exp. 1 and 2, respectively. In Exp. 1, CS did not differ (P ≥ 0.26) between BAND and BAND-MEL on any d, but castrates exhibited less desirable CS on d 1 and 28 than SHAM cattle. In Exp. 2, CS was not affected (P ≥ 0.41) by castration or the presence of meloxicam. In Exp. 2, DIST did not differ (P = 0.57) between BAND and BAND-MEL, but when pooled, castrates exhibited greater (P = 0.04) DIST than SHAM. In Exp. 2, plasma SP concentrations were similar between BAND and BAND-MEL (P = 0.81), and castrates vs. sham cattle (P = 0.67). Results indicate no impact of meloxicam administration on performance or behavioral and physiological responses to band castration. However, there was a negative impact of castration on ADG and DIST.
Colorado State University
Fort Collins, Colorado, United States
- Department of Animal Sciences
Universidade Estadual de Maringá
Maringá, Paraná, Brazil
- Chemistry Department
North Carolina State University
Raleigh, North Carolina, United States
- Department of Animal Science