Hot Carcass Weight Research Articles

277 Effect of yeast probiotics in lactation and nursery diets on progeny lifetime growth performance, immune response, and carcass characteristics

Abstract Mixed parity sows (n = 28; Line 241; DNA) and their offspring were used in a farrow-to-finish study to evaluate the effect of live yeast supplementation during lactation with or without yeast extract supplementation during the nursery period on sow and litter performance and lifetime growth performance, antibody titers, and carcass characteristics. Sows were blocked by parity and body weight (BW) on d 110 of gestation and allotted to 1 of 2 dietary treatments with 14 replications per treatment which consisted of a standard corn-soybean meal lactation diet with or without a yeast-based probiotic (0.10% Actisaf Sc 47 HR+; Phileo by Lesaffre, Milwaukee, WI). Following weaning, pigs (n = 350; 241×600, DNA; initial BW = 6.1 ± 0.02 kg) were randomly assigned in a 2 × 2 factorial design within sow treatment to 1 of 2 nursery diets which consisted of a control diet or a diet with pre-probiotic combination (0.10% MS309; Phileo by Lesaffre, Milwaukee, WI) fed for 42 d after weaning followed by common diets until marketing. Two nursery pens were combined in the finisher, such that there were 5 and 10 pigs/pen with 18 and 9 replications/treatment during the nursery and finishing periods, respectively. There were no significant effects of live yeast supplementation on lactation performance (P > 0.079). There was a sow × nursery diet interaction (P = 0.024) during the nursery period where pigs from sows fed Actisaf had increased average daily gain (ADG) when fed control nursery diets compared with pigs from control sows fed control nursery diets (Table). Pigs fed MS309 in the nursery from either sow treatment were intermediate. Pigs from sows fed Actisaf tended to be heavier at marketing (P = 0.067) with heavier hot carcass weight (HCW; P = 0.101), but there were no differences in overall finishing growth performance with the inclusion of yeast in lactation diets or nursery diets (P > 0.10). A subset of pigs were sampled at 7 time points to determine serum porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae antibody sample-to-positive (S/P) ratios and at 5 time points to ascertain percent inhibition of Lawsonia intracellularis. For all 3 immunological criteria, there were no sow diet × nursery diet × day interactions. There was a sow diet × day interaction for PCV2 S/P ratio (P = 0.097) where offspring from Actisaf sows tended to have greater PCV2 S/P ratios at 101 d of age compared with offspring from control sows (P = 0.046). There was a PCV2 S/P ratio nursery diet × day interaction (P = 0.036) where pigs fed MS309 had reduced PCV2 S/P ratios at 66, 78, and 162 d of age (P ≤ 0.022). In conclusion, feeding a pre/probiotic combination in the nursery did not affect performance or immune criteria. Conversely, feeding a live yeast probiotic during lactation resulted in tendencies for increased nursery ADG, final BW, and HCW.

31 Effects of dietary standardized ileal digestible (SID) lysine (Lys) levels and dietary SID tryptophan to Lys ratios on growth performance and behavior of late-nursery to finish maternal barrows

Abstract The objective was to determine the effects of dietary standardized ileal digestible (SID) lysine (Lys) levels and SID tryptophan (Trp) to Lys ratios on growth performance and behavior of late-nursery to finish maternal barrows. A total of 2,293 barrows (PIC Camborough, initially 11.9 ± 0.35 kg) were used in this trial with 96 mixed-sex pens and 23 to 25 pigs/pen. There was a total of 6 dietary phases: P1:11.9-29.5 kg; P2:29.5-49.6 kg; P3:49.6-62.6 kg; P4:62.6-80.3 kg; P5:80.3-103.3 kg; and P6:103.3-137.8 kg. Pens were blocked by body weight and randomly allotted to 1 of 6 treatments:T1: 100% Lys (dietary SID Lys levels meet PIC SID Lys recommendation) and 21.0% of SID Trp:Lys ratio; T2: 100% Lys and 18.5% of SID Trp:Lys ratio; T3: 100% Lys and 16.0% of SID Trp:Lys ratio; T4: 80% Lys (dietary SID Lys levels meet 80% of PIC SID Lys recommendation) and 21.0% of SID Trp:Lys ratio; T5: 80% Lys and 18.5% of SID Trp:Lys ratio; and T6: 80% Lys and 16.0% of SID Trp:Lys ratio for P1-P2 and then 100% Lys and 18.5% of SID Trp:Lys ratio for P3-P6. Ear lesion (EL) was monitored during P2-P5. Data were analyzed using a linear mixed model in R Studio (Version 3.5.2, R Core Team; Vienna, Austria). Pigs fed T1 and T2 showed improved average daily gain than T6 (P < 0.05), with other treatments intermediate (Table 1). Pigs fed T2 showed improved average daily feed intake as compared with T6 (P < 0.05), with other treatments intermediate. There was no evidence for significant difference on feed-to-gain ratio or mortality. Removal was significantly greater for pigs fed T6 compared with all other treatments (P < 0.05). Pigs fed T2 had significantly greater hot carcass weight than T4, with other treatments intermediate. There was no evidence for significant differences on carcass yield or lean percentage. Pig fed T6 had significantly greater incidence of EL in P2 than all other treatments (P < 0.05). Pigs fed T4 and T6 had greater incidence of EL in P3 than T1 (P < 0.05), with other treatments intermediate. Pigs fed T5 and T6 had significantly greater incidence of EL in P4 than T1, T2, and T3 (P < 0.05), with T4 intermediate. During P5, pigs fed T4 and T5 had the greatest incidence of EL (P < 0.05), while pigs fed T6 had significant greater incidence of EL than T3 (P < 0.05), with T1 and T2 intermediate. In conclusion, dietary SID Lys and SID Trp:Lys ratio less than PIC recommendation during late-nursery-to-grower phase resulted in compromised overall growth performance of maternal barrows, even with restored dietary SID Lys and SID Trp:Lys levels in finish phase. Dietary SID Lys level and/or SID Trp:Lys ratios lower than PIC recommendation may result in greater incidence of aggression behavior in maternal barrows.

PSV-13 The influence of diet type on beef cattle performance and meat quality characteristics

Abstract The objective of this study was to determine what additive effect hormonal implants and inclusion of beta-agonists in the diet have on carcass quality in yearling beef steers. Hereford-cross steers [n = 21; initial body weight (BW) = 450 ± 15 kg] were assigned to one of three drylot pens based on initial BW and sire so that each pen had an equal starting BW and sires were equally represented in each pen. Each drylot pen was assigned to one of three treatments: receiving a hormonal implant (IMP), consuming a beta-agonist (BAG), or receiving both of the previous treatments (AND). All steers were fed a mixed ration consisting of 30.0% rye silage, 28.0% DDGS, 30.0% rolled corn, 10.5% soybean meal, and 1.5% mineral supplement [22.0% CP, 2.90 Mcal ME/kg dry matter (DM)]. Animals were fed daily at 0700 and 1700 h and weighed weekly at 0630 h. For the duration of the trial, animals were housed in drylot pens with ad libitum access to feed and water and had shade structures in each pen. Following a 15-d adaptation period, feed intake was recorded for 45 d. Body weight gain for each treatment group were 1.26, 1.28, and 1.48 kg/d for IMP, BAG, and AND, respectively. Animals on the AND treatment were significantly more feed efficient than the IMP treatment with F:G ratios of 5.9 kg/kg gain and 6.8 kg/kg gain, respectively. After the intake portion of the study was completed, an animal from each pen was slaughtered and evaluated for carcass quality. Hot carcass weights for diets IMP, BAG, and AND were 347.4, 352.9, and 394.8 kg, respectively. Data were analyzed as a completely random design in SAS v9.4. There was not a significant difference between the IMP treatment and the AND treatment based on assessment from Warner-Bratzler shear force, carcass yield, marbling score, and sensory assessment (P > 0.05); however, the BAG treatment had less marbling than the other two treatments. It was concluded that the additive effect of using both a hormonal implant and a beta-agonist can improve feed intake and feedlot performance without detrimental effects on carcass quality.

251 Effects of feeding increasing levels of dimethylglycine (DMG) on growth performance, livability, and carcass characteristics of commercial finishing pigs

Abstract This study aimed to evaluate the impact of increasing dietary levels of 78% sodium dimethylglycine (DMG) on growth performance, livability, and carcass characteristics of commercial finishing pigs. A total of 1,115 mixed-sex finishing pigs [initial body weight (BW) = 70.1 ± 1.8 kg] were housed in pens with 25 to 27 pigs per pen. Pens within block were assigned randomly to one of four dietary treatments containing 0 (Control), 0.25 (DMG_0.25), 0.5 (DMG_0.5) or 1.0 (DMG_1.0) g DMG/kg of feed with 11 replicates per treatment. This experiment extended over an 8-wk period until pigs were harvested at 125.4 ± 0.8 kg of BW. Data were analyzed using the MIXED procedure of SAS, and preplanned orthogonal contrasts were conducted to evaluate pairwise comparisons as well as linear and quadratic effects related to the increased levels of DMG. While no linear effect was observed, there was a tendency for a quadratic response in closeout feed efficiency (G/F; P = 0.08) and the percentage of pigs with morbidity (P = 0.06), with the most favorable responses found in pigs fed DMG_0.25 (Table 1). Pairwise comparisons between Control and DMG_0.25 treatments suggest that pigs receiving DMG_0.25 showed a 6% increase in closeout average daily gain (ADG; 1.01 vs. 0.95 kg/d; P = 0.02) and a 4% increase in closeout G/F (0.337 vs. 0.324; P = 0.05) compared with those fed Control diet. Furthermore, DMG supplemented at 0.25 g/kg tended to be associated with decreased mortality (P = 0.08), reduced morbidity (P = 0.09) and more pigs sold to the primary market (P = 0.10) compared with Control. In contrast, dietary supplementation of greater concentrations of DMG at 0.5 and 1.0 g/kg were not different compared with Control (P > 0.10). Carcass characteristics, including hot carcass weight, carcass yield, fat depth, loin depth, and fat-free carcass lean, were not different among treatments. The findings of this study suggest dietary supplementation of DMG at 0.25 g/kg of feed enhanced growth performance and livability in finishing pigs. However, feeding greater concentrations of DMG, up to 1.0 g/kg of feed, did not produce different outcomes compared with Control. These results indicate the potential benefits of DMG at specific inclusion rate in optimizing the production and health of finishing pigs.

PSVI-1 Backgrounding and finishing systems for cattle fed corn silages and corn grains differing in amylase expression

Abstract Amylase is a key enzyme involved in the hydrolysis of starch, which typically constitutes the predominant source of energy in feedlot cattle diets. Performance of cattle during the backgrounding phase can influence performance during the subsequent finishing phase. Our objective was to assess growth performance of backgrounding steers fed diets that contained combinations of corn silage (S) and steam-flaked corn (G) from hybrids with high amylase expression (Enogen corn; E; Syngenta Seeds, LLC) or common corn hybrid (C), as well as subsequent finishing performance, carcass characteristics, and liver abscess incidence when fed G produced from the same hybrids. Crossbred steers (n = 911; 306 ± 8 kg initial body weight) were assigned randomly to one of four backgrounding treatments with 12 replicates in a randomized complete block experiment using a factorial treatment arrangement. Factor 1 consisted of two corn silage hybrids (ES or CS), and factor 2 consisted of two SFC hybrids (EG or CG). In the subsequent finishing phase, animals were assigned to one of two treatments consisting of two grain hybrids (EG or CG) with 24 replicates per treatment. Backgrounding diets (dry basis) contained 20.1% flaked corn and 41.6% corn silage, and finishing diets contained 81.5% flaked corn with triticale silage as a common roughage source. There was no three-way interaction for measures of interest, and no differences among treatment combinations with respect to average daily gain (ADG) or incidence of abscessed livers (P > 0.10). Steers fed CG during the backgrounding phase ate more than steers fed EG (P = 0.04), thus leading to improved overall efficiency of steers fed EG in the backgrounding phase compared with their counterparts fed CG (P < 0.01; Table 1). Overall efficiency tended to be greater for cattle fed CG during the finishing phase (P = 0.06) compared with cattle fed EG during the finishing phase. There was a tendency for interaction between G fed in the backgrounding and G fed in the finishing phase for hot carcass weight (P = 0.07), such that steers fed the same hybrid in both phases had greater carcass weight compared with those fed different hybrids in the backgrounding and finishing phases. Type of grain fed in the backgrounding and finishing phases, but not silage, impacted overall system efficiency.

PSV-6 The additive effect of hormonal implant and inclusion of beta-agonists in carcass quality in beef cattle

Abstract The objective of this study was to determine what additive effect hormonal implants and inclusion of beta-agonists in the diet have on carcass quality in yearling beef steers. Twenty-one Hereford-cross steers (450 ± 15 kg) were assigned to one of three drylot pens based on initial body weight (BW) and sire so that each pen had an equal starting BW and sires were equally represented in each pen. Each drylot pen was assigned to one of three treatments: receiving a hormonal implant (IMP), consuming a beta-agonist (BAG), or receiving both of the previous treatments (AND). All steers were fed a mixed ration consisting of 30.0% rye silage, 28.0% DDGS, 30.0% rolled corn, 10.5% soybean meal, and 1.5% mineral supplement (22.0% CP, 2.90 Mcal ME/kg DM). Animals were fed daily at 0700 and 1700 and weighed weekly at 0630. For the duration of the trial, animals were housed in drylot pens with ad libitum access to feed and water and had shade structures in each pen. Following a 15-d adaptation period, feed intake was recorded for 45 d. Weight gain for each treatment group were 1.26, 1.28, and 1.48 kg/d for IMP, BAG, and AND, respectively. After the intake portion of the study was completed, an animal from each pen was slaughtered and evaluated for carcass quality. Hot carcass weights for diets IMP, BAG, and AND were 347.4, 352.9, and 394.8 kg, respectively. Following 14 d aging, samples from the ribeye area were collected from each animal and subjected to sensory analysis and other assessments of quality. Data were analyzed as a completely random design in SAS v9.4. There was not a significant difference between the IMP treatment and the AND treatment based on assessment from Warner-Bratzler shear force, carcass yield, marbling score, and sensory assessment (P < 0.05); however, the BAG treatment had significantly less marbling than the other two treatments. It was concluded that the additive effect of using both a hormonal implant and a beta-agonist can produce carcass of good quality without detrimental effects on meat quality when compared with a beta-agonist only inclusion.

High deoxynivalenol and ergot alkaloid levels in wheat grain: effects on growth performance, carcass traits, rumen fermentation, and blood parameters of feedlot cattle

This study was designed to assess the impacts of a mixture of deoxynivalenol (DON) and ergot alkaloids (EAs) on growth performance, rumen function, blood parameters, and carcass traits of feedlot cattle. Forty steers (450 ± 6.0 kg) were stratified by weight and randomly allocated to 1 of 4 treatments; control-low (CON-L), control-high (CON-H) which contained low or high wheat screenings that lacked mycotoxins at the same level as the mycotoxin-low (MYC-L; 5.0 mg/kg DON, 2.1 mg/kg EA), and mycotoxin-high (MYC-H: 10 mg/kg DON, 4.2 mg/kg EA) diets that included wheat screening with mycotoxins. Steers were housed in individual pens for a 112-day finishing trial. Intake was 24.8% lower (P < 0.001) for MYC steers compared to CON steers. As a result, average daily gains of MYC steers were 42.1% lower (P < 0.001) than CON steers. Gain to feed ratio was also lower (P < 0.001) for MYC steers compared to CON steers. Platelets, alanine aminotransferase, globulins, and blood urea nitrogen were lower (P ≤ 0.008), and lymphocytes, glutathione peroxidase activity (GPx), and interleukin-10 (IL-10) were elevated (P ≤ 0.002) in MYC steers compared to CON steers. Hot carcass weights and backfat thickness were reduced (P < 0.001) in MYC steers, resulting in leaner (P < 0.001) carcasses and higher (P < 0.007) meat yield compared to CON steers. Results suggest that a mixture of DON and EAs negatively impacted health, performance, and carcass traits of feedlot steers, with the majority of this response likely attributable to EAs. However, more research is needed to distinguish the relative contribution of each mycotoxin to the specific responses observed.

Feeding pomegranate pulp to Ghezel lambs for enhanced productivity and meat quality

Agrifood by-products contain nutrients and bioactive compounds that can be used in the diets of livestock – thereby value-adding to an otherwise waste product of environmental and economic significance. This study investigated the effect of dietary pomegranate pulp in the total mixed ration of Ghezel lambs, evaluating its effect on growth performance, blood parameters, carcass traits, as well as meat quality and shelf life. 3-month-old Ghezel lambs (individually housed, n = 8) were randomly assigned to be either non-supplemented (control) or supplemented with 100 g/kg DM of sun-dried pomegranate pulp for 28 days, post-adjustment. Results showed that supplementation of lamb diets with pomegranate pulp significantly increased liveweight and average daily gains, while not significantly affecting dry matter intake. Lamb serum urea and alkaline phosphatase concentrations and hot carcass weight were increased with pomegranate pulp supplementation. Compared to control lambs, the meat from lambs fed the supplemented diet had higher concentrations of intramuscular fat, mono- and polyunsaturated fatty acid, total unsaturated fatty acid, and meat phenolic compounds. Pomegranate pulp supplemented lambs also had a higher ratio of polyunsaturated to saturated fatty acids; and produced liver tissue with less fat and ash contents. Meat oxidative status (thiobarbituric acid reactive substance) and quality (water holding capacity, colour, and pH) were improved when lambs were supplemented with pomegranate pulp. These findings demonstrate that using pomegranate pulp as a feed for Ghezel lambs has advantageous effects on animal performance and meat quality, offering valorisation of an agrifood by-product.

Exposure to Prenatal Tributyrin Improved Pre-Weaning Growth Performance and Reduced Fat Deposition in the Muscle of Market Age Pigs

Organic acids, including short chain fatty acids, medium chain fatty acids, and tricarboxylic acid, are used as alternatives to antibiotics for the purpose of growth promotion in livestock species. Butyric acid has been used extensively for its various functions in intestinal health and barrier function, as well as its actions as a histone deacetylase inhibitor. Many of the issues related to using butyric acid as a feed supplement are overcome by utilizing tributyrin (TB), a butyrate prodrug. Dietary supplementation of TB to sows during gestation was able to improve pre-weaning litter performance. Sows (n=52, 42 gestational days) were randomly assigned to either a control diet or control diet supplemented with 2% TB. All diets were made isocaloric with the addition of oil and wheat flour. Dietary treatments continued until 112 days of gestation. After farrowing, piglet growth performance was monitored. Once offspring reached 6 months of age, 30 gilts from the most median performing litters were identified for tissue collection and evaluation of meat characteristics. Sows that received tributyrin during gestation tended to have higher total litter weights at birth (P value &lt; 0.1), however, average individual birthweights were not statistically different between control and TB litters. TB piglets tended to be heavier at weaning (P value &lt; 0.1). Pre-weaning average daily gains were higher in piglets exposed to prenatal TB (P value &lt; 0.01). Live weights and hot carcass weights did not differ significantly in gilts at market age. There was, however, a trend of increased dressing percentage from TB treated offspring, accompanied by significantly reduced back fat at the 10th rib (P value &lt; 0.1 and P value &lt; 0.05 respectively). This data suggests that TB supplementation results in both temporary and permanent improvements to growth and development. This study provides further evidence that prenatal TB can have long term effects on muscle growth and meat quality. Further studies are needed to ultimately determine whether prenatal or postnatal supplementation is ideal for improving long-term growth performance. USDA Grant Funded. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Prediction of Live Weight and Carcass Characteristics from Linear Body Measurements of Yearling Male Local Sheep

Measurements of the body structure in sheep are worthy of judging the quantitative features of meat and useful in developing appropriate selection requirements. The current study was aimed to predict live weight and hot carcass weight from linear body measurements of yearling male local sheep. 84 days feeding period fortnightly taken data on 24 local sheep for body weight, body length, heart girth, wither height, sub-sternal height, tail length, tail width, scrotal circumference, and scrotal length were analyzed to study the relationship between linear body measurements and body weight. At the end of the trial all sheep were slaughtered to measure the relationship between body measurements, and hot carcass weight. Microsoft Excel 2010 was used for data analysis. The relationships between the various body measurements were calculated using pearson's correlation coefficient. The backward stepwise multiple regression procedure was used for the determination of the most suitable model for the prediction of the live weight and hot carcass weight. Hot carcass weight was highly correlated (P&lt;0.01) with body weight and scrotal circumference. Besides, it was significantly (P&lt;0.05) correlated with tail width. Body weight was significantly (P&lt;0.05) correlated with all body measurements except tail length and scrotal length. It is concluded that the body weight of the local sheep can be predicted with heart girth, sub-sternal height and tail width; the equation is LW= -97.2 + 0.36HG + 2.1SBSH + 0.57TW with a better coefficient of determination; R2 = 0.55 and the hot carcass weight can be predicted with sub-sternal height and tail width; the equation is HCW= -75.66 + 1.75SBSH + 0.85TW with a coefficient of determination; R2 = 0.33. But, hot carcass can be predicted with body weight, the equation is HCW= -9.39+0.85BWT when weighing scales are affordable with a better coefficient of determination; R2= 0.557.

Effects of Zilpaterol Hydrochloride with a Combination of Vitamin D3 on Feedlot Lambs: Growth Performance, Dietary Energetics, Carcass Traits, and Meat Quality.

This study evaluated the impact of supplementing ZH in combination with D3 on the growth performance, energy efficiency, carcass traits, and meat quality of feedlot lambs. Thirty-two Dorper × Katahdin cross lambs (37.3 ± 5.72 kg) were utilized in a 29 d experiment in a completely randomized block design with a 2 × 2 factorial structure consisting of two levels of ZH for 26 d (0 and 0.20 mg/kg PV-1) and two levels of D3 for 7 d (0 and 1.5 × 106 IU/d-1). ZH improved (p ≤ 0.05) the average daily gain (ADG) and feed efficiency by 9.9% and 17.8%, respectively, as well as hot carcass weight (HCW) and dressing carcass by 4.3% and 2.6%, respectively. (p ≤ 0.03). However, ZH increased (p < 0.01) muscle pH and Warner-Bratzler shear force (WBSF) (2.5 and 23.0%, respectively). D3 supplementation negatively affected (p ≤ 0.02) dry matter intake (DMI) (last 7 d) and ADG by 15.7% and 18.1%. On the other hand, D3 improved the pH of the longissimus thoracis muscle by 1.7% (p = 0.03) without affecting WBSF. When D3 was supplemented in combination with ZH, it was observed that meat quality was improved by reducing muscle pH compared to lambs treated only with ZH. However, D3 did not improve the meat tenderness negatively affected by ZH supplementation.

The importance of developmental programming in the beef industry

The beef industry relies on multiple focused segments (e.g., cow-calf, stocker/feeder, and meat packing) to supply the world with beef. Thus, the potential impact of developmental programming on the beef industry needs to be evaluated with regards to the different production traits that drive profitability within each segment. For example, when nutrient restriction of dams occurred early in gestation embryo survival was decreased and the ovarian reserve of heifer progeny was negatively affected. Restriction during mid- to late gestation negatively impacted first service conception rates and pregnancy success of daughters. Even non-nutrient stress has been reported to impact transgenerational embryo development through the male progeny. Primary and secondary muscle fibers form during months two to eight (Days 60–240) of gestation. Therefore, external stimuli (nutrition or environmental) during this window have the potential to decrease the postnatal number of muscle fibers; which has an irreversible impact on animal growth and performance. Nutrient restriction during the last third of gestation resulted in decreased weaning weights, and in some instances decreased dry mater intake, hot carcass weight, and marbling scores. Protein supplementation during late gestation; however, increased weaning weight and ADG to weaning, but progeny of dams restricted in protein in late gestation had greater ribeye area. The importance of developmental programming is recognized; however, its precise application depends on comprehension of its integrated effects across the multiple-focused segments of the beef industry.

Three-dimensional imaging to estimate in vivo body and carcass chemical composition of growing beef-on-dairy crossbred bulls

The dynamics of cattle body chemical composition during growth and fattening periods determine animal performance and beef carcass quality. The aim of this study was to estimate the empty body (EB) and carcass chemical composition of growing beef-on-dairy crossbred bulls (Brown Swiss breed as dam with Angus, Limousin or Simmental as sire) using three-dimensional (3D) imaging. The 3D images of the cattle’s external body shape were recorded in vivo on 48 bulls along growth trajectory (75–520 kg BW and 34–306 kg hot carcass weight [HCW]; set 1) and on 70 bulls at target market slaughter weight, including 18 animals from set 1 (average 517 ± 10 kg BW and 289 ± 10 kg HCW; set 2). The linear, circumference, curve, surface and volume measurements on the 3D body shape were determined. Those predictive variables were used in partial least square regressions, together with the effect of the sire breed whenever significant (P < 0.05), with leave-one-out cross-validation to estimate water, lipid, protein, mineral and energy mass or proportions in the EB and carcass. Mass and proportions were determined directly from postmortem grinding and chemical analyses (set 1) or indirectly using the 11th rib dissection method (set 2). In set 1, bulls’ BW and HCW were estimated via 3D imaging, with root mean square error of prediction (RMSEP) of 12 kg and 6 kg, respectively. The EB and carcass chemical component proportions were estimated with RMSEP from 0.2% for EB minerals (observed mean 3.7 ± 0.2%) to 1.8% for EB lipid (11.6 ± 4.2%), close to the RMSEP found for the carcass. In set 2, the RMSEP for estimation via 3D imaging was 9 kg for BW and 6 kg for HCW. The EB energy and protein proportions were estimated, with RMSEP of 0.5 MJ/kg fresh matter (10.1 ± 0.8 MJ/DM) and 0.2% (18.7 ± 0.7%), respectively. Overall, the estimations of chemical component proportions from 3D imaging were slightly less precise for both sets than the mass estimations. The morphological traits from the 3D images appeared to be precise estimators of BW, HCW as well as EB and carcass chemical component masses and proportions.

Effect of dawri-damaa (Pentas schimperiana) leaf meal supplementation on performances, carcass characteristics, and economic feasibility of sheep fed native grass hay.

With a growing export and local market, sheep farming is critical to the economy of smallholder farmers; however, indigenous sheep breeds usually exhibit low carcass output and live weight due to nutritional constraints. The study aimed to investigate the impact of supplementing local sheep with dawri-damaa leaf meal (DDLM) on their performance, carcass characteristics, and profitability when fed native grass hay. The research used a randomized complete block design (RCBD) to administer four feeding treatments (T1, T2, T3, and T4 at 0%, 30%, 50%, and 70% DDLM, respectively) to 20 local uncastrated male lambs having an average 23.72 ± 0.73 kg body weight and average age of 11.72 ± 0.74 months. Greater doses of DDLM in the diet resulted in greater average daily gain (ADG) of 51.4-83.8 g/day and feed conversion efficiency (FCE) of 0.066-0.089 in lambs, compared to 15.0 g/day ADG and 0.025 FCE in lambs under control diet (T1). Additionally, the lambs had increased slaughter body weight (SBW), empty body weight (EBW), and hot carcass weight (HCW) in T4 and T3 compared to other treatments (p < .05). There were no significant differences in dressing percentages (DPs) across any treatment group. The study also discussed the economic viability of supplementing with DDLM, suggesting that feeding 70% daily dry matter of DDLM at 2.5% live weight might be beneficial depending on availability, access, and cost factors. In conclusion, feeding DDLM up to 70% has improved the performance of sheep and is economically feasible. Further research might be required to discover whether such levels of inclusion are harmful and apply different processing methods for feeding animals.

Associations between the rumen microbiota and carcass merit and meat quality in beef cattle

The rumen microbiota is important for energy and nutrient acquisition in cattle, and therefore its composition may also affect carcass merit and meat quality attributes. In this study, we examined the associations between archaeal and bacterial taxa in the rumen microbiota of beef cattle and 12 different attributes, including hot carcass weight (HCW), dressing percentage, ribeye area (REA), intramuscular fat content, marbling score, fat thickness, yield grade, moisture content, purge loss, and shear force. There were significant correlations between the relative abundance of certain archaeal and bacterial genera and these attributes. Notably, Selenomonas spp. were positively correlated with live weight and HCW, while also being negatively correlated with purge loss. Members of the Christensenellaceae R-7, Moryella, and Prevotella genera exhibited positive and significant correlations with various attributes, such as dressing percentage and intramuscular fat content. Ruminococcaceae UCG-001 was negatively correlated with live weight, HCW, and dressing percentage, while Acidaminococcus and Succinivibrionaceae UCG-001 were negatively correlated with intramuscular fat content, moisture content, and marbling score. Overall, our findings suggest that specific changes in the rumen microbiota could be a valuable tool to improve beef carcass merit and meat quality attributes. Additional research is required to better understand the relationship between the rumen microbiota and these attributes, with the potential to develop microbiome-targeted strategies for enhancing beef production.Key points• Certain rumen bacteria were associated with carcass merit and meat quality• Moryella was positively correlated with intramuscular fat in beef carcasses• Acidaminococcus spp. was negatively correlated with marbling and intramuscular fat

Effect of breed and sex on the body weight, slaughter traits, meat quality and meat texture parameters of rabbits

The purpose of the study was to determine the influence of breed on the growth, slaughter traits, quality traits and parameters of texture of meat obtained from Blanc de Termonde and Flemish Giant rabbits. Young animals were weaned on the 35th day of their life. The weight of animals was recorded from birth to the 84th day of life at 7-day intervals. The rabbits were slaughtered between 85th and 90th day of live. Hot carcass weight, chilled carcass weight and giblets weight (liver, lung and heart, kidneys) were recorded. The pH and the colour of the longissimus lumborum and biceps femoris muscles was measured in 45th minute and at 24 hours after slaughter. Shear force and texture parameters were measured. Flemish Giant achieve higher final body weight but lower dressing out percentage than Blanc de Termonde rabbits. Carcasses of Blanc de Termonde characterized with higher loin weight and fat content in carcass. The effect of breed fount to be significant for some components of meat colour like yellowness (b*) in 45th minute and lightness after 24 hours post mortem. The effect of sex found to be significant for acidity of meat and b* component in 45th minute after slaughter and on redness (a*) after 24 hours post mortem. Statistically significant differences between Flemish Giant and Blanc de Termonde rabbits in shear force and texture profile analysis (TPA) were stated. The sex of animals effected only on chewiness parameter for TPA of rabbit meat.

Carcass and non-carcass component yields of trenbolone acetate + estradiol-17β implanted steers vs. non-implanted steers across serial harvest endpoints

ObjectiveWe investigated incremental growth of carcass and non-carcass components and tissue partitioning of implanted or non-implanted steers. Materials and MethodsSteers (n = 80; 271 ± 45 kg) were paired and randomized to harvest date (d 0, 42, 84, 126, 168, 210, 252, 294, 336, or 378), and individuals within pairs were randomized to CON (negative control) or REV (Revalor-XS, Merck Animal Health, on d 0 and 190) treatments. Non-carcass components were removed, cleaned, and weighed. Growth coefficients were calculated using the allometric equation Y = bXa. Results and DiscussionEmpty body weight (EBW), and hot carcass weight (HCW) were 6% greater (P < 0.01) in REV steers versus CON. No treatment effects (P ≥ 0.12) occurred for fill or dressed carcass yield (DY); however, EBW, HCW, and DY increased (P ≤ 0.01) and percentage fill decreased as an effect of days on feed (DOF). Absolute fill weight did not change across DOF (P = 0.82). Implanted steers had greater (P ≤ 0.05) absolute mass of blood, head, hide, oxtail, liver, spleen, bladder, heart, reticulum, omasum, stomach, small intestine, intestines, gastrointestinal tract (GIT), total splanchnic tissue, and total offal. Implanted steers also had smaller (P ≤ 0.05) absolute mass of thymus glands and kidney-pelvic- heart fat (KPH) than non-implanted steers. Non-carcass components with lowest growth coefficients included small intestine (0.02), large intestine (0.12), and brain and spinal cord (0.13). However, KPH (2.01) accumulated at more than 2 times the rate of the empty body, whereas cod fat (1.42) and GIT fat (1.61) grew notably faster than the empty body. Implication and ApplicationsResults suggest that Revalor-XS increased body and carcass weights and altered many non-carcass components and their growth co- efficients, ultimately playing key biological, nutritional, and financial roles across sectors of the beef industry.

Influence of Beef Hot Carcass Weight on Sensory Characteristics of Strip Loin, Eye of Round, and Denver Cut Steaks.

The objective of this research was to investigate the influence of beef hot carcass weight (HCW) on consumer sensory attributes. Beef carcasses (n = 116) were selected based on the USDA quality grade and HCW. Lightweight (LW; 296-341 kg), middleweight (MW; 386-432 kg), or heavyweight (HW; 466-524 kg) carcasses with USDA Choice (LC) or USDA Select (SEL) quality grades were used in this study. Carcasses were tracked through fabrication and the semitendinosus, chuck roll, and strip loin were collected and fabricated into eye of round, Denver cut, and strip loin steaks, respectively, for consumer sensory evaluation. USDA Select MW Denver cut steaks had increased overall liking and texture liking scores and were more tender and juicier than the SEL LW steaks (p ≤ 0.02). USDA Select MW strip loin steaks had increased overall and flavor liking scores and were more tender than the SEL LW steaks (p ≤ 0.02). USDA Choice MW eye of round steaks had increased overall, flavor, and texture liking scores and were juicier than the LW eye of round steaks (p ≤ 0.04). The steaks evaluated in this study were differentially impacted by HCW and little to no clear pattern of effects could be determined across cut or quality grade. Additional research is needed to determine the most acceptable HCW from a consumer perspective.

Effect of supplementing zilpaterol hydrochloride during different periods on energetics, growth performance, carcass traits and fatty acid profile in meat of finishing lambs

To determine the effect of adding β2 agonist zilpaterol hydrochloride during different periods on growth performance, dietary energetic, carcass traits and fatty acid profile, forty male lambs Pelibuey × Katahdin (37.70 ± 0.83 kg) were blocked by body weight and randomly assigned to pens. Treatments consisted in: 1) control, no zilpaterol supplementation, 2) zilpaterol supplementation for 20 d (ZIL20), 3) zilpaterol supplementation for 30 d (ZIL30), and 4) zilpaterol supplementation for 40 d (ZIL40). Compared with control treatment, zilpaterol supplementation increased final live weight (FLW) (3.5 %; P = 0.0563), average daily gain (ADG, 14.8 %; P = 0.0598) and gain:feed ratio (10.3 %; P = 0.0324). As well as hot carcass weight (6.1 %; P = 0.0064), dress out percentage (2.6 %; P = 0.0139) and Longissimus dorsi muscle area (13.7 %; P = 0.0015). Compared to control group, zilpaterol increased (P = 0.0413) observed vs. expected dietary of NEm (net energy requirements for maintenance) and NEg (net energy requirements for growth) (5.7 and 8.1 %, respectively). Twenty days of zilpaterol treatment improved FLW (4.4 %, P = 0.0566) and tended to improve ADG (17.4 %, P = 0.0718) when compared to control group. Only intramuscular fat showed a positive linear effect (P = 0.0006) in stearic fatty acids proportion and negative linear effect (P = 0.0585) in araquidonic fatty acid proportion. We conclude that zilpaterol hydrochloride improved variables of growth performance, energy retention and carcass traits with noticeable effects from 20 d of zilpaterol supplementation.

Influence of Finishing Systems on Carcass Characteristics, Composition, and Fatty Acid Profile of Bison Bulls

The objective of this study was to determine the influence of grain- and grass-finishing systems on carcass characteristics of bison bulls and proximate and fatty acid compositions of bison steaks. Bison bulls grazed native pasture until approximately 25 mo of age, then were randomly assigned to grain-finishing (n=98) or grass-finishing (n=98) treatments. Bulls were slaughtered at approximately 30 mo of age. Hot carcass weight (HCW), ribeye area, backfat thickness, kidney fat percentage, marbling score, and instrumental color (L*,a*, and b*) of the ribeye and subcutaneous fat were recorded. Skeletal maturity, lean maturity, and fat color were subjectively scored. Strip loins were collected from a sub-sample of carcasses, fabricated into 2.5-cm steaks, and designated for proximate, cholesterol, or fatty acid analyses. Grain-finished bulls had greater (P&amp;lt;0.0001) HCW, dressing percentage, ribeye area, backfat thickness, kidney fat percentage,and marbling score. The a* and b* values of the ribeye and a* value of subcutaneous fat were greater (P&amp;lt;0.0001), but the L* and b* values of subcutaneous fat were less (P&amp;lt;0.0001) for grain-finished bulls. A greater proportion (P&amp;lt;0.001) of grain-finished carcasses had moderately bright red lean color, whereas a greater proportion (P&amp;lt;0.0001) of grass-finished carcasses had moderately yellow fat color. Steaks from grain-finished bulls had an increased percentage of crude protein (P&amp;lt;0.0001), fat (P&amp;lt;0.0001), and ash (P=0.0006) content but less moisture (P&amp;lt;0.0001). Steaks from grain-finished bulls had more (P&amp;lt;0.001) cholesterol and palmitic, stearic, oleic, linoleic, and arachidonic acids in addition to more total fatty acids (mg/g of wet tissue). However, for total fatty acids, grass-finished steaks had a greater (P&amp;lt;0.0001) percentage of polyunsaturated fatty acids. These data indicate that the finishing system influences the composition of bison bull carcasses as well as the nutrient profile of bison meat.