Carcass Yield Research Articles

Effect of a Simultaneous Increase in Crude Protein and Total Digestible Nutrients Contents on Late Fattening Hanwoo Steers

Background: Shortening the fattening period can reduce production costs and inedible fat, but may simultaneously negatively affect productivity and profitability. We hypothesized that increasing the crude protein and total digestible nutrients (TDN) in the formula feed could address the issues associated with shortened fattening periods without adversely affecting rumen fermentation. This study investigated the effect of a simultaneous increase of crude protein and TDN contents compared to conventional formula feed on growth performance, blood metabolites, carcass characteristics and meat composition of late fattening Hanwoo steers. Methods: Thirty Hanwoo steers were randomly assigned to one of two dietary groups: control group (16.4% crude protein and 83.6% TDN based on dry matter) and treatment group (17.4% crude protein and 84.6% TDN based on dry matter). Result: The rumen parameters were similar between the control and treatment groups. Likewise, the effect of additional crude protein and TDN contents in the formula feed showed no significant impact on the growth performance or blood metabolites. The carcass weight and yield index were slightly higher in the treatment group compared to the control, yet these differences were not statistically significant. Furthermore, the dietary treatment did not affect marbling score, meat color, fat color, texture, maturity, pH, surface colors, drip loss, cooking loss, sensory characteristics, or fatty acid composition in the longissimus muscle.

Assessment of body metrics, weight, and carcass yields in dusky grouper (Epinephelus marginatus) through correlation and path analysis: Implications for optimizing genetic breeding programs

One of the objectives of aquaculture selective breeding programs is to enhance body conformation traits, often by using indirect criteria like correlation between live body measurements and carcass traits. This research investigated the relationship between live body measurements and carcass traits in dusky grouper (Epinephelus marginatus). We assessed the relationship between body measurements and carcass traits in 150 farmed dusky groupers with an average weight of 680 ± 221 g. The fish were measured for length, width, height, and length of head, and then processed to obtain weights (body, fillet, steaks, head, and residues) and yields (carcass, fillet, steaks, head, and residues). Path analysis was employed to estimate direct and indirect effects, with body part weight and yields as dependent variables and morphometric measurements and relationships as explanatory variables. The findings indicate that morphometric measurements can be used to estimate farmed dusky grouper body weights and carcass yields. Among the morphometric measurements and relationships examined, fish body height and standard length were identified as the main factors influencing variation in body weights and carcass yields.

The influence of dietary supplementation with fermented agro-industrial residue of faba bean on Japanese quail performance, immunity, gut microbiota, blood chemistry, and antioxidant status

Antibiotic overuse in poultry feeds has disastrous implications; consequently, long-term alternatives must be developed. As a result, the current study aims to assess the impact of Aspergillus niger filtrate (ANF) high in organic acids grown on agro-industrial residue of faba bean (AIRFB) on quail diet, as well as their influence on bird productivity, digestion, carcass yield, blood chemistry, and intestinal microbiota. A total of 240 Japanese quails (aged 7 d) were used in this study, divided equally among 5 experimental groups with 48 quails each. Group 1 (G1) received a basal diet without any ANF, group 2 (G2) received a basal diet supplemented with 0.5 mL ANF/kg diet, group 3 (G3) received a basal diet supplemented with 1.0 mL ANF/kg diet, group 4 (G4) received a basal diet supplemented with 1.5 mL ANF/kg diet, and group 5 (G5) received a basal diet supplemented with 2 mL ANF/kg diet. The performance parameters were monitored at 1 to 3, 3 to 5, and 1 to 5 wk. Adding ANF increased body weight at 3 and 5 wk, as well as body weight gain at 1 to 3, 3 to 5, and 1 to 5 wk, compared to the control diet. The ANF fed quails had the highest feed conversion ratio compared to the control group. The addition of ANF to the quail diet had no effect on the weight of the carcass, gizzard, heart, liver, giblets, or dressing; however, it did lower triglycerides, low-density lipoprotein, and very low-density lipoprotein while increasing high-density lipoprotein levels. The quail groups that received ANF had enhanced immunological indices such as IgG, IgM, IgA, and lysozymes. It also increased the levels of superoxide dismutase and total antioxidant contents, as well as catalase, and digestive enzymes such as protease, amylase, and lipase. However, it lowered the blood MDA levels compared to control. It has been demonstrated that the total gut microbiota, Escherichia coli, total coliforms, and the population of Salmonella are all reduced in ANF-fed quails. Histological examination of ANF quails' liver and intestinal sections revealed normal hepatic parenchyma, typical leaf-like intestinal villi, and comparatively short and frequently free lumina. In conclusion, Japanese quail showed improvements in performance, digestive enzymes, antioxidant indices, immunity, and capacity to reduce intestinal pathogenic bacteria after consuming diet supplemented with ANF.

Aspartic protease supplementation enhancing the performance, carcass characteristics, nutrient digestibility and economic viability, without changing blood parameters and salivary cortisol of pigs

Aiming to study the performance, carcass characteristics, nutrient digestibility, blood parameters, salivary cortisol levels, and economic viability of pigs administered aspartic protease, a total of 135 pigs were housed in pens in a randomized block design, divided into five treatments with nine replications. The experimental diets were positive control (PC), basic diet with a 5.0% reduction in protein and amino acid requirements; negative control (NC) with a 7.5% reduction in protein and amino acid requirements; NC + 100 g/mT of aspartic protease (NC100); NC + 150 g/mT of aspartic protease (NC150); and NC + 200 g/mT of neutral serine protease (NC200). The inclusion of protease, independently of the source and amount, increased the average daily weight gain (P < 0.05) of animals compared with the control treatments (PC and NC), improved feed conversion (P < 0.05) in early stages, and improved diet digestibility (P < 0.05) compared with the PC. Treatment with NC150 and NC200 resulted in greater carcass weights (P < 0.05) than treatment with the PC. NC100 led to a greater carcass yield than PC (P < 0.05), and NC150 resulted in a greater loin eye area than PC (P < 0.05). No differences (P > 0.05) in the blood parameters or salivary cortisol levels were found. Regarding economic viability, proteases increased the profitability, with NC150 leading to the best results. Thus, the use of aspartic proteases is recommended to improve performance and further facilitate pork production.

Evaluation of Carcass, Growth Performance, Hematological and Biochemical Parameters of Broiler Chickens Fed Additive of Onion Bulb Peel Powder

The study evaluated the effect of the powder of onion bulb peel waste (Allium cepa) as feed additives on growth performance, blood profile and carcass features of broiler chickens. A total of 150-day old Arbo acre strains of broiler chicks were randomly allocated into five treatments group with 30 birds in each treatment with three replicates of 10 birds each. The birds were reared on the floor of a pen partitioned into experimental units. The study was conducted in two phases; starter phase (0-28 day) and finisher phase (28-56 day). A basal experimental diet was formulated for the broiler chickens and varying levels of onion bulb peel powder was added as a supplement at 0mg/kg (control), 25mg/kg, 50mg/kg, 75mg/kg and 100mg/kg in diets 1, 2, 3, 4 and 5 respectively. Feed and water were provided ad libitum. The results obtained in this study revealed that there was significant difference (p&lt;0.05) in feed intake, body weight, daily weight gain, feed conversion ratio, hematological and bio-chemical parameters, carcass weight, non-carcass weight, percentage of carcass cut-part relative to the dressed weight and percentage non carcass relative to live weight between treatment diets. Onion bulb peel powder at 100mg/kg enhanced growth performance, reduced total blood cholesterol, triglyceride and low-density lipoprotein, increased the high-density lipoprotein cholesterol and improved carcass yield of the birds. Since the feeding of onion bulb peel powder up to 100mg/kg as feed additives did not constitute nutritional disorder or any adverse effect on heamatological parameters of broiler chickens, it can be concluded that onion bulb peel powder at this level of inclusion is good for broiler chicken production.

Nutritional value of meat from selected neotropical reptiles

This is the second part of a two-part review. The first part focused on the nutritive value of meat and meat products of selected neo-tropical mammals with the potential for domestication. The objective of this current review was to investigate the nutritional qualities and carcass traits of selected neotropical reptiles compared to domestic species, focusing on the spectacled caiman, iguana, tegu, and yellow anaconda. Carcass weight analysis revealed that the spectacled caiman and male iguana were efficient converters of live weight to edible carcass weight, with higher yields than other reptiles. Among domestic species, pigs and chickens showed higher carcass yields compared to cattle and lamb. Moisture content in reptile meat was generally higher than in domestic animals, impacting texture and juiciness. Protein content was lower in reptiles but still contributed to daily requirements, while fat content, though generally lower in reptiles, could impact flavor and tenderness. Cholesterol levels were lower in reptiles, particularly the yellow anaconda, making them potentially healthier options for those with cardiovascular concerns. Fatty acid composition analysis indicated varying levels of saturated, monounsaturated, and polyunsaturated fatty acids, with potential cardiovascular health benefits in reptile meats. Amino acid content, though lower in reptiles compared to domestic species, provided essential building blocks for various physiological functions. Overall, the study highlighted the nutritional value and potential health benefits of including neotropical reptile meat in the human diet, especially as alternative protein sources.

Effect of corn–soybean meal-based diets with low calcium and available phosphorus in male broilers on performance, tibia criteria and jejunum histomorphology

Abstract This study was conducted to determine the effect of reducing calcium (Ca) and available phosphorus (AvP) on performance, carcass yield, tibia traits and jejunum histomorphology in broilers. For this purpose, 480 one-day-old Ross 308 male chicks were distributed into four trial groups with eight subgroups. During the starter period, birds were fed with recommended or reduced Ca and AvP contents of 66.7 and 62.5 g/kg, respectively. Calcium and AvP contents of the groups were as follows: control: 8.70 g/kg Ca, 4.40 g/kg AvP for grower and 7.80 g/kg Ca, 3.90 g/kg AvP for finisher; LCP1: 8.30 g/kg Ca, 4.20 g/kg AvP for grower and 7.10 g/kg Ca, 3.50 g/kg AvP for finisher; LCP2: 7.90 g/kg Ca, 4.00 g/kg AvP for grower and 6.00 g/kg Ca, 3.00 g/kg AvP for finisher; LCP3: 7.00 g/kg Ca, 3.80 g/kg for grower and 5.00 g/kg Ca, 3.00 g/kg AvP for finisher. Performance variables have been calculated from the data of each period, and samples were obtained from the slaughtered birds on the final day of the trial (42nd day) for carcass and tibia traits and jejunum histomorphology. Reducing dietary Ca and AvP did not affect the broiler performance, carcass yield and mortality. Tibia ash decreased in LCP2 and LCP3 groups (P &lt; 0.01). Villus width and villus surface area increased in LCP2 and LCP3. Overall, feeding with a diet 100 g/kg lower than the recommended Ca and AvP did not affect performance in broilers, but improved jejunal development.

30 Effects of using different dietary standardized ileal digestible lysine plans on growth performance and carcass characteristics of grow-finish pigs from high or low breeding value boars

Abstract The present study aimed to evaluate the impact of using different dietary standardized ileal digestible (SID) lysine (Lys) plans on growth performance and carcass characteristics of grow-finish pigs coming from high or low breeding value boars. A total of 2,080 pigs (PIC 800 × PIC Camborough) were housed in 20 mixed sex pens (26 pigs/pen), blocked by body weight (BW), and randomly allotted in a 2 × 2 factorial arrangement with boar breeding value (high or low) and nutrition Lys plan (current SID Lys curve recommendation for PIC 800 as % of PIC 337 SID Lys curve or alternative SID Lys curve). Pigs were weaned at 21 d of age (6.1 ± 0.05 kg BW) and followed during the wean-to-finish period until reach the market slaughter weight. Pigs were fed either the current recommendation or an alternative SID Lys curve for PIC 800, in a 6 phase feeding program: phase 1 (6-11 kg; 100 vs 100%, respectively); phase 2 (11-23 kg; 97 vs 100%, respectively); phase 3 (23-45 kg; 97 vs 100%, respectively); phase 4 (45-73 kg; 97 vs 95%, respectively); phase 5 (73-102 kg; 97 vs 95%, respectively); and phase 6 (102-132 kg; 97 vs 90%, respectively). Pigs were fed isoenergetic diets. Performance and carcass traits, and removals and mortality were recorded. Data were analyzed using mixed models in R, and considering pen as the experimental unit for performance traits and individual carcasses for carcass traits. There was no evidence of interaction between boar breeding value and nutrition plan factors. Overall, high breeding value pigs had greater average daily gain (ADG; 0.84 ± 0.005 g/d) compared with low breeding value pigs (0.82 ± 0.005 kg/d; P &amp;lt; 0.01), which was driven by increased average daily feed intake (ADFI; 1.92 ± 0.011 and 1.89 ± 0.011 kg/d, respectively; P &amp;lt; 0.05; Table 1). Moreover, high breeding value pigs had greater hot carcass weight (HCW; 97.8 ± 1.09 kg), carcass yield (74.1 ± 0.23%), backfat thickness (16.3 ± 0.29 mm) and lower lean meat % (57.0 ± 0.21%) compared with low breeding value pigs (96.0 ± 1.09 kg; 73.7 ± 0.23 %; 15.4 ± 0.28; 57.5 ± 0.21%, respectively; P &amp;lt; 0.05; Table 1). Regarding nutrition plan, no significant differences were observed for overall performance traits between pigs fed the current or alternative SID Lys curve (P &amp;gt; 0.05; Table 1). Nevertheless, pigs fed the alternative SID Lys curve had heavier HCW (97.3 ± 1.09 kg) compared with pigs fed the current SID Lys curve (96.6±1.09 kg; P &amp;lt; 0.05; Table 1). No significant differences were observed for overall removals and mortality by breeding value or nutrition Lys plan (P &amp;gt; 0.05). In summary, grow finish pigs from high breeding value boars have an improved productive performance. PIC 800 pigs may achieve the same productive performance with lower lysine levels at the end of the grow-finish period.

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 &amp;lt; 0.05), with other treatments intermediate (Table 1). Pigs fed T2 showed improved average daily feed intake as compared with T6 (P &amp;lt; 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 &amp;lt; 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 &amp;lt; 0.05). Pigs fed T4 and T6 had greater incidence of EL in P3 than T1 (P &amp;lt; 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 &amp;lt; 0.05), with T4 intermediate. During P5, pigs fed T4 and T5 had the greatest incidence of EL (P &amp;lt; 0.05), while pigs fed T6 had significant greater incidence of EL than T3 (P &amp;lt; 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 &amp;gt; 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.

57 Effect of diet mixing strategies on growth performance and carcass characteristic in feedlot steer

Abstract Our objective was to determine the effects of a feeding management strategy on growth and carcass quality and characteristics on finishing feedlot beef cattle. Angus-Simmental steers (n = 60), blocked by body weight (BW), were housed in individual pens and randomly assigned to treatments. Treatments were total mixed ration (TMR) or a non-mixed diet (Split). The diet contained 67.5% of dry rolled corn, 18% of distiller grains with soluble, 2.5% soybean meal, 7% hay, and 5% of mineral and vitamin mixed. The diet composition for both treatments was similar, the only difference was the use of a TMR or that the concentrate was fed separately from the hay on the Split treated calves. Feed intake was monitored through slick bunk management in both treatments. For the Split assigned calves, if any hay or concentrate was left in the bunk on two consecutive days, the total feed was decreased by 5%; maintaining always the 93% concentrate and 7% forage ratio. Steers were weighed monthly and feed samples were collected for nutrient composition analysis semimonthly. Monthly weights and intakes were used to calculate average daily gain (ADG) and gain to feed ratio (G:F). Steers were slaughtered per block when the average weight of the block reached 555 kg. Carcasses were evaluated 48 h post slaughter. Carcass yield and quality factors were evaluated at the 12th/13th rib interface. Data were analyzed as randomized complete block design. Considering the fixed effect of the feeding strategy and the random effect of block. We did not observe differences (P &amp;gt; 0.17) in growth performance or carcass characteristics variables due to management strategy (Table 1). The lack of observed differences due to treatment might be because the ratio of concentrate and forage intake was similar for both groups, in addition to the slick bunk management in both treatments, which forced steers to eat all their ration, independent of the treatment, to continue to receive the same amount of feed.

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 &amp;gt; 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.

24 Effects of reducing dietary net energy on growth performance and carcass characteristics of grow-finish pigs

Abstract This study was conducted to evaluate the effects of dietary NE on growth performance, carcass characteristics, and removal and mortality rates of grow-finish pigs. A total of 1,927 pigs [initial body weight (BW) 23.3 ± 0.23 kg] were used in a 125-d study. Pens of pigs were blocked by BW and randomly allotted to dietary treatments in a randomized complete block design with 23 to 26 pigs/pen and 15 replications/treatment. Pens received 1 of 5 diets with decreasing NE based on Eq. 1-8 NRC (2012) using proximate analysis of the major ingredients. A corn-soybean meal-based control diet was blended with a low energy diet that contained 8% less NE through inclusion of 25% wheat middlings and 15% DDGS (6% oil) to achieve intermediate NE levels. Thus, dietary NE fed through 5 dietary phases were: phase 1 (2,432, 2,383, 2,335, 2,286, and 2,237 kcal/kg); phase 2 (2,463, 2,413, 2,363, 2,315, and 2,266 kcal/kg); phase 3 (2,495, 2,445, 2,395, 2,345, and 2,295); phase 4 (2,518, 2,468, 2,417, 2,367, and 2,317 kcal/kg); and phase 5 (2,537, 2,486, 2,435, 2,384, 2,334 kcal/kg). Dietary phases were fed from approximately 23-40, 40-60, 60-80, 80-105, and 105-133 kg BW, respectively. Overall, reducing NE decreased (linear, P &amp;lt; 0.001) average daily gain (ADG) and final BW and increased (linear, P &amp;lt; 0.001) average daily feed intake (ADFI), resulting in decreased (linear, P &amp;lt; 0.001) gain to feed ratio (G:F; Table). Decreasing NE also tended to increase (linear, P = 0.073) the percentage of removals, with no evidence of difference (P &amp;gt; 0.10) in mortality. Reducing NE worsened (linear, P &amp;lt; 0.001) caloric efficiency (CE) based on NRC nutrient loading values, but improved (linear, P ≤ 0.003) CE based on INRA (2008) or Brazilian Tables for Poultry and Swine (2017) nutrient loading values. When formulating diets using CVB (2021) nutrient loading values, decreasing NE did not influence CE (P &amp;gt; 0.10). For carcass characteristics, decreasing NE decreased (linear, P &amp;lt; 0.001) HCW, backfat depth, and carcass yield. However, decreasing NE increased (linear, P ≤ 0.024) loin depth and percentage lean. When considering CE on a carcass gain basis, decreasing NE worsened (linear, P ≤ 0.004) CE based on NRC or CVB nutrient loading values, but improved (linear, P &amp;lt; 0.001) CE based on INRA nutrient loading values. Decreasing NE resulted in no differences (P &amp;gt; 0.010) in CE based on Brazilian Tables nutrient loading values. These results suggest that the NRC database overestimates NE contributions of fibrous ingredients, such as wheat middlings and corn DDGS, while the INRA database underestimates their contributions to NE, whether CE is calculated based on live or carcass gain. Meanwhile, NE values in the CVB database appear to assess nutrient values more accurately for NE based on live gain but underestimate their value on a carcass basis. The Brazilian tables appear to underestimate the contributions of fibrous ingredients to dietary NE on a live basis, but more accurately value their contributions on a carcass basis.

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 &amp;lt; 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.

252 Evaluation of phase feeding and complete diet blending at different standardized ileal digestible lysine levels on finishing pig growth performance, carcass characteristics and diet costs

Abstract A total of 2,160 mixed-gender pigs [PIC 337 × 1050; initial body weight (BW) = 24.9 ± 0.97 kg) were used in the 120-d study to compare feeding strategies (phase feeding vs complete diet blending) at different SID Lys levels (90 vs 100% of suggested requirement estimates) on finishing pig growth performance, carcass characteristics, and economics. Pens of 27 pigs were assigned to 1 of 4 treatments in a completely randomized block design with barn and initial BW as blocking factors resulting in 20 pens/treatment. The treatments included two feeding programs: a 5-phase feeding strategy at either 90% (Phase-90) or 100% of SID Lys requirement estimates (Phase-100) or blending of complete diets with pre-defined mixing proportions of a low and high SID Lys diet to meet 90 (Blend-90) or 100% (Blend-100) of the SID Lys curve requirement estimates for 23 to 127 kg pigs. Lysine levels were based on PIC 2021 requirement estimates. The 90% SID Lys diets were formulated to contain 4.38, 3.73, 3.06, 2.66 and 2.44 g SID Lys per Mcal NE for phases 1 to 5, respectively. The 100% SID Lys diets were formulated to contain 4.86, 4.15, 3.40, 2.96 and 2.71 g SID Lys per Mcal NE for phases 1 to 5, respectively. Pigs in phase-feeding strategies were fed on a feed budget with 21, 65, 67, 63 and 62 kg per pig for phases 1 to 5, respectively. Final BW and overall average daily gain (ADG; d 0 to 120) were not affected by the feeding strategy nor by diet SID Lys levels. In contrast, overall average daily feed intake (ADFI0 of pigs fed by diet blending was less than those fed by phase feeding (P = 0.002) resulting in increased gain to feed ratio (G:F; P &amp;lt; 0.001) for pigs fed by diet blending (table). The SID Lys levels did not influence overall ADFI or G:F. Hot carcass weight, carcass yield, percentage lean, fat depth and loin depth were not affected by the feeding program. Despite the decreased overall ADFI and increased G:F of pigs fed by diet blending, feeding strategy resulted in no significant differences in economic criteria except for reduced feed cost per kg gain at high price scenario (P = 0.049) for diet blending. With low diet cost, the 90% SID Lys level resulted in decreased feed cost per pig and feed cost per kg gain than 100% SID Lys (P &amp;lt; 0.001), but differences were not detected in income over feed cost (IOFC). In conclusion, diet blending at either 90 or 100% of the SID Lys requirement estimate reduced ADFI and increased G:F without impacting average daily gain (ADG) or carcass characteristics. At ingredient prices used in this study, feeding strategies at either 90 or 100% SID Lys did not significantly affect IOFC, but feeding 90% of SID Lys recommendation reduced feed cost.

53 Evaluation of the impact of high doses of phytase and marketing strategy on performance and carcass characteristics of late finishing pigs in commercial settings

Abstract As late finishing pigs reach market weight, space allowance per unit of body weight (BW) is reduced, which negatively impacts growth performance. Supplementing high doses of phytase results in the near complete destruction of phytic acid resulting in increased levels of lower inositol esters and inositol, which have been associated with a decreased stress response as well as having insulin-like effects. This study evaluated the impacts of high doses of phytase and two marketing strategies on growth performance and carcass characteristics of late finishing pigs. Pigs (n = 2,200; initial BW = 89.64 ± 3.08 kg) were randomly distributed to 96 pens using two commercial research barns, with 18 to 24 pigs per pen, balanced for gilts and barrows. Two phytase supplementation doses (super-dosing control of 2,250 FTU/kg and hyper-dosing at 4,500 FTU/kg) and two marketing strategies (Standard or Late) were combined to create 4 treatments in a 2×2 factorial arrangement. The first marketing event occurred at an average BW of 123.3 kg on d 22 for the Standard group and at 145.3 kg on d 44 for the Late group, marketing the heaviest 1 to 5 pigs per pen (13.2% of pigs). The second group (15.4% of pigs; BW of 147.3 and 144.8 kg for Standard and Late marketing) was marketed on d 50 and marketing of all remaining pigs occurred on d 63 for both treatments. Finisher diets contained 0.74% SID lysine, 0.60% Ca, and 0.37% available P. Regardless of the dose, phytase was given the same matrix values for nutrients and metabolizable energy. No interactions were observed between marketing strategy and phytase supplementation (P &amp;gt; 0.22), and no effect of phytase was observed (P &amp;gt; 0.09). Average BW of all pigs marketed was greater (P &amp;lt; 0.001) for the Late compared with the Standard marketing strategy (143.8 vs. 141.7 kg/d). Days to market was greater for Late marketing (59.7 vs. 56.8 d) as a result of the extra 22 d before the first marketing compared with the Standard strategy. Thus, average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio were not impacted (P ≥ 0.486) by marketing treatments. Hot carcass weight (103.83 vs. 101.44 kg) and yield (78.10 vs. 77.73%) were greater (P &amp;lt; 0.001) for Late marketing. Fat cover was greater and percent lean was less (P &amp;lt; 0.05) for the Late marketing treatment, but loin depth and marbling were not different (P &amp;gt; 0.09). All primal cuts were heavier (P &amp;lt; 0.001), resulting in a total primal weight of 89.44 and 87.54 kg (P &amp;lt; 0.001) for Late and Standard marketing, respectively. Results suggest that delaying the first marketing improved final BW, yield, and weight of primal cuts and that supplementing phytase above super-dosing levels in late finishing pigs did not improve growth performance or carcass value, regardless of marketing strategy.

28 Investigation of protein deposition pattern of PIC337×Camborough commercial pigs

Abstract The objective of the trial was to investigate the protein deposition pattern of PIC337×Camborough commercial pigs. A total of 1,064 barrows and gilts [PIC337×Camborough, initial body weight (BW) = 6.0 ± 0.1 kg] were used in the trial with 38 mixed sex pens, 28 pigs per pen. At the beginning of the trial, the lightest 10% of the barrows and gilts were selected and placed in four pens (equal numbers of barrows and gilts within a pen), and the remaining pigs were randomly placed into the other pens (equal numbers of barrows and gilts within a pen). A common 6-phase corn-soybean based wean-to-finish diets were fed throughout the trial. Dietary net energy and standardized ileal digestible lysine levels were (6-10 kg BW: 2,600 Kcal/kg and 1.35%; 10-20 kg BW: 2,520 Kcal/kg and 1.30%; 20-38 kg BW: 2,470 Kcal/kg and 1.20%; 38-72 kg BW: 2,450 Kcal/kg and 0.98%; 72-127 kg BW: 2,450 Kcal/kg and 0.87%; and 127-149 kg BW: 2,450 Kcal/kg and 0.77%). On d 97 after placement, 5 barrows and 5 gilts with BW close to pen average were selected for individual BW by a portable scale and 10th rib backfat and loin depth measurements (ExaGo portable ultrasound scanner, Imv imaging, UK). Then on d 111, 117, 136, 142, and 167 after placement, the same 5 barrows and 5 gilts were measured for individual BW, 10th rib backfat and loin depth. The fat-free lean mass is estimated by the equation 6.783-0.6198×(10th rib backfat depth, mm)+0.1578×(10th rib loin depth, mm)+1.0362×(warm carcass weight, kg). A constant carcass yield of 75% was used to estimate warm carcass weight. Data were analyzed using a linear mixed model in R Studio (Version 3.5.2, R Core Team; Vienna, Austria). The average BW of pigs at the 6 measurements were: 77.2, 92.4, 99.2, 122.5, 128.0, and 153.6 kg, respectively. The average daily gain (ADG) was 1,139, 1,155, 1,145, 1,126, and 977 g/d for 77.2 to 92.4 kg BW, 92.4 to 99.2 kg BW, 99.2 to 122.5 kg BW, 122.5 to 128.0 kg BW, and 128.0 to 153.6 kg BW, respectively. The average daily 10th rib backfat depth gain was 0.05, 0.08, 0.15, 0.17, and 0.20 mm/d. The average daily 10th rib loin depth gain was 0.42, 0.43, 0.41, 0.39, and 0.23 mm/d. The average daily fat-free lean mass gain (ADFFLG) was 547, 551, 528, 515, and 422 g/d. The fitted quadratic model for ADG is 83.57782 + 19.90632 × (BW, kg)-0.09176×(BW, kg)2, and the calculated maximum ADG was 1,163 g/d when BW was 108.5 kg. The fitted quadratic model for ADFFLG is 85.90926 + 9.23773 × (BW, kg) - 0.04591 × (BW, kg)2, and the calculated maximum ADFFLG is 550.6 g/d when BW was 100.6 kg. Under the conditions of the current trial, PIC337×Camborough pigs reaches the maximum rate of protein deposition at BW between 100.6 and 108.5 kg.

247 Evaluating the use of soybean hulls on growth performance, carcass composition, and digestibility when fed to grow-finish pigs

Abstract The addition of fiber to grow-finish diets is commonly utilized in swine production formulation as energy costs increase. The objective of this study was to determine the effects of feeding soybean hulls (SBH) at increasing levels to grow-finish pigs on growth performance, carcass characteristics, and apparent total tract digestibility (ATTD) of nutrients. Utilizing 192 grower pigs [PIC 337×1050, initial body weight (BW) = 21.99 ± 2.75 kg] that were randomly assigned to split sexed pens (n = 12 pens/treatment), pens were assigned to one of four dietary treatments and fed over three feeding phases for the estimated BW ranges of 22 to 50 kg, 50 to 86 kg, and 86 to 127 kg. Diets were formulated to represent conventional corn and soybean meal diets, containing increasing levels of SBH at: 1) 0% SBH (0%); 2) 7.5% SBH (7.5%); 3) 15% SBH (15%); and 4) 22.5% SBH (22.5%). Within phase, diets had equal SID Lys:ME and energy was allowed to float. Individual BW and pen feed disappearance were collected for each phase to calculate pen average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency gain to feed ratio (G:F). On d 56 of study and during phase 2, 32 gilts (n = 8) were placed into individual metabolism crates, where total urine and feces were collected for 72 h to measure ATTD of gross energy (GE), nitrogen (N), neutral detergent fiber (NDF), and acid detergent fiber (ADF), then returned to original pens. At the completion of study, carcass weight, backfat depth, and loin depth were collected. Data were analyzed with the fixed effects of dietary treatment by ANOVA, linear, and quadratic contrasts. Pen served as the experimental unit for performance and carcass characteristics and pig as the experimental unit for ATTD analyses. Overall, as SBH increased from 0% to 22.5%, ADG tended to decrease (linear P = 0.060) with no difference in ADFI (P &amp;gt; 0.05), resulting in an overall decrease in G:F (0.38, 0.37, 0.36, 0.35; linear P &amp;lt; 0.001; 0, 7.5, 15 and 22.5% SBH, respectively). Final BW tended to decrease (linear P = 0.069) and carcass weight decreased (102.9, 102.7, 99.7, and 96.5 kg, linear P &amp;lt; 0.001) as SBH increased in diet. Carcass fat depth (P = 0.014) and loin depth (P = 0.006) linearly decreased with increasing levels of SBH in the diet. Increasing levels of SBH from 0% to 22.5% decreased ATTD of GE and N (linear P &amp;lt; 0.001) and tended to increase ATTD NDF and ADF (linear P = 0.056 and P = 0.073, respectively). Altogether, these data suggest increasing dietary SBH in grow-finish pig diets decreases growth efficiency and the digestibility of GE and N. Further, feeding high inclusion rates of SBH negatively impacts carcass yield, backfat and loin depth.

Comparative effects of proteases on performance, carcass traits and gut structure of broilers fed diets reduced in protein and amino acids

This study aimed to evaluate the effect of supplementing different protease enzymes on growth performance, intestinal morphology, and selected carcass traits in broilers fed diets reduced 3.5% in crude protein (CP) and amino acids (AA). One thousand one-day-old Ross 308 broilers (41 g) were assigned to five dietary treatments with ten replicates of 20 birds each: (PC) a positive control diet formulated to meet Ross 308 amino acid requirements, (NC) a negative control diet reformulated to provide 3.5% lower CP and AA compared to PC, (PR1) NC supplemented with a multi-protease solution, containing 3 different coated proteases produced from &lt;italic&gt;Aspergillus niger, Bacillus subtilis&lt;/italic&gt; and &lt;italic&gt;Bacillus licheniformis&lt;/italic&gt;, (PR2) NC supplemented with a serine protease produced from &lt;italic&gt;Bacillus licheniformis&lt;/italic&gt;, and (PR3) NC supplemented with an alkaline protease produced from &lt;italic&gt;Bacillus licheniformis&lt;/italic&gt;. At slaughter, 40 birds per treatment were used to assess the effect of the different treatments on carcass traits. At 32 days, samples of the duodenum, jejunum, and ileum of 10 birds per treatment were collected for intestinal morphology evaluation. Birds fed PC and NC supplemented with multi-protease exhibited better (&lt;italic&gt;p&lt;/italic&gt; &amp;lt; 0.05) feed efficiency compared to NC and NC supplemented with all the other protease enzymes. Multi-protease supplementation was linked to the highest (&lt;italic&gt;p&lt;/italic&gt; &amp;lt; 0.05) carcass weight and yield. There were significant differences (&lt;italic&gt;p&lt;/italic&gt; &amp;lt; 0.05) between treatments in all gut segments, with PC, PR1, PR2, and PR3 exhibiting longer villi height (VH) compared to NC. This study demonstrates that 3.5% reduction of CP and AA negatively affected for the overall period feed efficiency, carcass yield, and intestinal morphology. The supplementation of the multi-protease restored feed efficiency and improved carcass yield.

Effect of different bedding depths of rice hulls on growth performance and carcass traits of White Pekin ducks.

Duck meat is recognized as a healthier poultry product that contains higher amounts of unsaturated and essential fatty acids, iron, and excellent amounts of protein. It has been found to possess the ability to reduce low-density lipoprotein cholesterol and subsequently, blood pressure in the human body; and improve the immunity system. The current study investigated the appropriate bedding depths of rice hulls as a preferred bedding material by evaluating the growth performance and carcass traits of White Pekin ducks raised for 42 days. A total of 288 one-day-old White Pekin ducklings were randomly allotted to floor cages with one of four bedding depths at 4 cm, 8 cm, 12 cm, and 16 cm. Ducklings were fed standard duck starter (days 1-21) and finisher (days 22-42) diets. The birds were stocked at a rate of 6 birds/m2 with 6 replicates per treatment. Growth performance evaluation for the body weight, average daily gain, and average daily feed intake were measured to calculate the weekly feed conversion ratio. Breast, leg, and carcass yield were assessed as carcass traits. The muscle color and proximate composition were also analyzed for meat quality. Footpad dermatitis was also evaluated on day 42. Ducks reared on 16 cm bedding depth over the 42 days recorded higher (p < 0.05) body weight, average daily, average daily feed intake, and improved feed conversion ratios compared to other groups. The crude fat in breast meat also lowered (p < 0.05) in ducks reared at 16 cm (1.02%) when compared to ducks raised at 4 cm bedding depth (2.11%). Our results showed improved redness (p < 0.05) when the depth of bedding materials was elevated. Except for the breast meat fat, the dissimilar bedding depths did not affect (p < 0.05) the breast and leg meat composition, footpad dermatitis, and mortality for the current study. In conclusion, this study indicated that the bedding depths would directly or indirectly affect the growth performance and meat color of White Pekin ducks; and the bedding depth of rice hulls at 16 cm improved the growth performance of White Pekin ducks for 42 days.