Cold Carcass Weight Research Articles

Effect of dietary Marula (Sclerocarya birrea caffra) nut meal on the growth performance, carcass traits and meat quality of Dorper lambs

Use of Marula nut meal (MNM) to replace Soyabean meal (SBM) as a dietary protein source in lamb fattening diets by determining effects on growth performance, carcass yield and meat quality was evaluated. MNM replaced SBM on a crude protein (CP) basis, in five diets, at 0%, 25%, 50%, 75% and 100%, respectively. Forty 112-day old entire male Dorper lambs (average body weight: 22.1 ± 3.3 kg) were randomly allocated to the diets and fed ad libitum for 63 days. Weekly and final body weight (FBW), body weight gain (BWG), average daily gain (ADG), daily feed intake (FI) and feed conversion ratio (FCR), warm and cold carcass weight, dressing percentage, meat (physical and chemical attributes) quality were determined. Dietary MNM caused no significant difference in FBW, BWG, ADG, FI, FCR, carcass weight and the meat’s physical attributes compared to SBM. At 25% and 100% dietary substitution of SBM (CP basis), MNM significantly (P < 0.05) reduced meat protein content. Feeding MNM-based diets produced meat with higher fat content compared to the control SBM diet (P < 0.05). The meat’s total monounsaturated fatty acid content, dominated by oleic acid, increased with increasing dietary MNM. At 100% substitution of SBM, dietary MNM produced meat with the highest (P < 0.05) oleic acid content. The results obtained in the study showed that MNM can replace SBM in lamb fattening diets without compromising growth performance, feed utilisation efficiency, carcass yield and physical attributes of meat. MNM can potentially be utilised to improve lamb quality by increasing its oleic acid content.

Inclusion of Berberis vulgaris leaf in the diet of fattening lambs: Effects on performance, nutrient intake, rumen fermentation, and carcass traits.

This study was aimed to first, determine the nutritional value of Berberis vulgaris leaf (BVL), using in-vitro gas production technique and second, determine the effect of replacing alfalfa hay (AH) with BVL in lamb diets on nutrient intake, performance, and carcass traits. In-vitro rumen gas kinetics and fermentation profile were assessed using three fistulated lambs and 96h incubation of samples. For the in-vivo trial, twenty-one Baluchi male lambs of 5-6 months of age and 30.6 ± 1.28kg body weight (BW) were randomly assigned to three treatment diets containing BVL at 0% (CTRL), 7.5% (BVL7.5), and 15% (BVL15) of the total dry matter (DM) inclusion. The study lasted 84 days, which included 14 days for adaption and 70 days for sample collection. In-vitro results showed that BVL had lower gas yield (GY24, p ≤ 0.05) than AH. In-vivo trial revealed that DMI increased with BVL15 followed by BVL7.5 (p ≤ 0.05). Digestibility of DM, OM, NDF, and ADL decreased (p ≤ 0.05) with BVL15. Total weight gain (TWG), average daily gain (ADG), hot carcass weight (HCW), and cold carcass weight (CCW) were decreased (p ≤ 0.05) with BVL15, however, no differences were observed between the BVL7.5 and CTRL groups. Feed cost per kg BW gain decrease (p ≤ 0.05) by increasing the inclusion levels of BVL. In conclusion, BVL (up to 7.5 % DM of diet) have positive consequences on performance, nutrient intake, rumen fermentation without deleterious effects on fattening performance.

Dynamics of subclinical pneumonia in male dairy calves in relation to antimicrobial therapy and production outcomes.

Quick thoracic ultrasonography (qTUS) is increasingly used as an on-farm method to diagnose clinical and subclinical pneumonia in dairy calves. The primary objective of this prospective cohort study was to describe dynamics of lung consolidation in a purchase-dependent production system for male dairy calves in relation to antimicrobial therapy and respiratory diagnostics. In addition, we studied the association of cured and uncured pneumonia with average daily gain (ADG) and cold carcass weight (CCW). The third objective was to determine the effects of arriving with lung consolidation on the probability of developing chronic unresponsive pneumonia and reduced performance. A total of 295 male dairy calves were intensively followed by qTUS and clinical scoring on 7 strategic occasions (wk 1, 2, 3, 4, 6, 8, and 12) during the production cycle. Of the calves, 17.6% (52/295) arrived with a lung consolidation ≥1 cm. At the first outbreak of respiratory disease (wk 1 after arrival), this incidence had risen to 30.8%. Initial therapy with tulathromycin and subsequently doxycycline appeared ineffective, resulting in a increase to 43.8% of calves having pneumonia in wk 4. At the start of the first outbreak (wk 1), the majority (86.8%) of the pneumonia cases were subclinical. At wk 4, the outbreak became more clinical, and treatment with amoxicillin resulted in a cure risk of 52.7%. Culture and nanopore sequencing diagnostics on nonendoscopic broncho-alveolar lavage (nBAL) samples identified bovine respiratory syncytial virus and Mycoplasma bovis as the dominant agents in the first outbreak. The isolated M. bovis strain showed mutations associated with macrolide resistance. The second outbreak was characterized by a Pasteurella multocida superinfection and isolation of multiple M. bovis strains from nBAL diagnostic testing. Evaluated over the complete observation period, 83.4% of the calves developed consolidations ≥1 cm on qTUS. Of these calves, 53.9% (135/246) were cured by antimicrobial therapy. Chronic pneumonia (≥30 subsequent days of pneumonia) was seen in 13.9% of the animals (n = 41). Calves with uncured or chronic pneumonia had a lower ADG (992 ± 174 g/d and 930 ± 146 g/d, respectively) compared with calves that never developed pneumonia (ADG = 1,103 ± 156 g/d). In contrast, calves that did fully cure trended toward a lower ADG than calves that never developed pneumonia, but differences were no longer significant. Also, the effect of uncured pneumonia was no longer significant for CCW. Calves with lung consolidation upon arrival had a lower ADG (981 ± 159 g/d vs. 1,045 ± 159 g/d) and were more likely to develop chronic pneumonia [odds ratio = 4.2; 95% confidence interval = 2.1-8.6] compared with calves without consolidation upon arrival. Animals with chronic pneumonia, in turn, had a lower CCW than animals without chronic pneumonia (10.3 ± 4.4 kg; 95% confidence interval: 1.6-19.1 kg). This study documents the consequences of subclinical pneumonia upon arrival and pneumonia developed later in the production cycle on production outcomes in a veal calf setting. Both qTUS and nBAL diagnostics provide important information, offering potential for better control and prevention of bovine respiratory disease in dairy calves.

Sexo e peso de abate sobre as características de carcaça e componentes não-carcaça de cavalos

ABSTRACT: The study evaluated the effect of sex and slaughter weight on carcass traits and non-carcass components of 1,489 horses (739 geldings and 750 females, classified into eight groups according to their weight). Data were analyzed under a completely randomized design. Geldings had a higher (P &lt; 0.05) hot carcass yield (HCY) and cold carcass yield (CCY) than females; however, fat yellowness values (b*) were greater (P &lt; 0.05) in females. Slaughter weight (SW) affected the carcass characteristics. Hot carcass weight (HCW), cold carcass weight (CCW), HCY, and CCY increased (P &lt; 0.05) in accordance with slaughter weight, while cool loss percentage (CL%) was lower (P &lt; 0.05) in horses weighing more than 300 kg. In addition, the non-carcass components decreased (P &lt; 0.05) as the weight of the horses increased. In conclusion, sex and body weight are factors to consider in the production of equine meat since they affect carcass characteristics and non-carcass components.

Desempenho zootécnico de cordeiros Dorper x Santa Inês criados em diferentes sistemas de produção

Abstract The objective of this work was to compare the zootechnical performance of Dorper x Santa Inês crossbred lambs finished in grazing systems on Megathyrsus maximus Aruana cultivar pasture, with and without shading, and in a feedlot. Twenty-four non-castrated lambs were used in a completely randomized experimental design, with the three following treatments with eight replicates each: 'Aruana' pasture without shading + supplement; 'Aruana' pasture with shading + supplement; and feedlot, with diet containing ryegrass hay and concentrate at a 20:80 ratio. The treatments did not influence lamb age at slaughter, birth weight, leg compactness, true yield, and main cut yield, except that of breast tip + flank that was lower for the pasture with shading. However, average daily gain, body condition score, live weight at slaughter, carcass compactness index, cold carcass and empty body weights, and cold carcass yield differed between treatments, showing higher values in the feedlot. Termination in the feedlot increases the zootechnical performance of Dorper x Santa Inês sheep and favors a lower age at slaughter, as well as a greater weight of the main commercial cuts, but not their yield.

Dieta de alto grão e inclusão de óleo residual de fritura na alimentação de cordeiros

Abstract In animal production, a large part of financial resources is destined to animal feed, so the use of low-cost diets with maximum production efficiency is crucial. The present study evaluated the effects of a high-grain diet and the use of residual frying oil on the productive performance and carcass characteristics of lambs. Fifteen lambs were distributed into three groups in a completely randomized design in which they were fed a control diet, a high-grain diet, or a diet with the inclusion of residual frying oil, for 40 days. There was no difference (P &gt; 0.05) between the control and frying-oil diets regarding the daily intakes of dry matter, crude protein, mineral matter, neutral detergent fiber, or total carbohydrates. The high-grain diet reduced the intake of dry matter and nutrients, negatively affecting weight gain. The highest means for final weight, total weight, and daily weight gain were obtained with the control diet and the diet containing residual oil, which did not differ from each other (P&gt; 0.05). Slaughter weight and hot and cold carcass weights decreased with the high-grain diet. There was an effect (P &lt; 0.05) of frying oil inclusion on the carcass characteristics of the lambs. The diets did not affect (P &gt; 0.05) carcass yields. The animals on the high-grain diet showed unsatisfactory production performance, with impaired carcass characteristics. The inclusion of frying oil led to greater weight gain as well as more attractive carcass characteristics, making it the most viable alternative in this research.

The Effect of Space Allowance During Pre-Slaughter Transport of European Quail Breeders on Welfare, Carcass Traits and Meat Quality

The objective was to evaluate whether space allowance during pre-slaughter transport of European breeding quail affects welfare, carcass traits and meat quality. A total of 248 quails (body weight = 344.90 ± 2.09 g) were used. During pre-transport, the quails were fasted for 5 hours and 30 minutes. The poultry were caught and placed in plastic transport crates with an area of 0.40 m2. The treatments consisted of a different space allowance in each crate: 22, 28, 34 or 40 quails per crate. Immediately upon arrival at the slaughterhouse, the quails were stunned. During bleeding, blood samples were collected. The carcasses were individually weighed. The meat quality was measured. Data were analysed using the effects of space allowance during transport of quails and pickup truck as dependent variables. Death on arrival increased as the space allowance in transport crates decreased (p=0.08). Glucose and uric acid levels were not significantly different between groups (p≥0.14). The cold carcass weight presented the maximum value when the crates contained 31 quails (p=0.03). The meat pH, intensity of red, intensity of yellow and cooking losses were not different between groups (p≥0.12). The meat lightness value presented the maximum value when the crates contained 31 quails (p=0.04). In view of the above, the number of European breeding quails transported in crates must not exceed 30 animals.

Effect of dental age on edible and non-edible meat yield characteristics of indigenous beef cattle

The objective of this study was to know the effect of dental age on the meat yield characteristics of indigenous beef carcasses. This experiment was conducted with five (5) treatments (T1, T2, T3, T4 and T5) where T1 = 0 Permanent incisor, T2 = 2 Permanent incisors, T3 = 4 Permanent incisors, T4 = 6 Permanent incisors, T5 = 8 Permanent incisors having ten (10) replications. From the experiment it shows that live and hot carcass weight increased significantly in T1 and T2 compared to T3, T4 and T5. Cold carcass weight (CCW) increased significantly with the advancement of dental maturity. KPH% was highest in T4 and lowest in T3 whereas round and loin% were highest in T4 and T3 respectively but both are lowest in T1. Lungs with trachea, liver and kidney weight% were significantly higher in T1 than others group. In conclusion, maximum live weight gain and hot carcass weight were achieved in the dental age groups of two to four permanent incisors.

Fitting Genomic Prediction Models with Different Marker Effects among Prefectures to Carcass Traits in Japanese Black Cattle.

We fitted statistical models, which assumed single-nucleotide polymorphism (SNP) marker effects differing across the fattened steers marketed into different prefectures, to the records for cold carcass weight (CW) and marbling score (MS) of 1036, 733, and 279 Japanese Black fattened steers marketed into Tottori, Hiroshima, and Hyogo prefectures in Japan, respectively. Genotype data on 33,059 SNPs was used. Five models that assume only common SNP effects to all the steers (model 1), common effects plus SNP effects differing between the steers marketed into Hyogo prefecture and others (model 2), only the SNP effects differing between Hyogo steers and others (model 3), common effects plus SNP effects specific to each prefecture (model 4), and only the effects specific to each prefecture (model 5) were exploited. For both traits, slightly lower values of residual variance than that of model 1 were estimated when fitting all other models. Estimated genetic correlation among the prefectures in models 2 and 4 ranged to 0.53 to 0.71, all &lt;0.8. These results might support that the SNP effects differ among the prefectures to some degree, although we discussed the necessity of careful consideration to interpret the current results.

A Descriptive Study on the Carcass, Muscle, and Offal Yields of the Plains Zebra (Equus quagga) Harvested in Two Seasons

This study presents descriptive data on the meat and offal production of Plains zebras harvested in the winter (n = 8) and summer (n = 12) seasons, at different respective locations in the Western Cape Province of South Africa. The cold dressing percentages were numerically higher for the winter (58.0 ± 0.60%) than for the summer-harvested animals (56.60 ± 0.70%). Heavier internal offal yields were reported for the winter-harvested group (70.76 ± 21.8 kg) compared to the summer-harvested animals (66.13 ± 3.78 kg). As harvest season had no influence, pooled data of the percentage contribution of each muscle to cold carcass weight indicated that the Longissimus et lumborum (3.5 ± 0.18%), semimembranosus (1.6 ± 0.04%), biceps femoris (2.7 ± 0.05%) and semitendinosus (0.9 ± 0.02%) muscles differed significantly in their respective contributions to cold carcass weight. No significant differences were recorded between the contribution of the infraspinatus (0.6 ± 0.02%), supraspinatus (0.4 ± 0.03%) and psoas major (0.6 ± 0.02%) muscles. Carcass and muscle yields, as well as low-cost protein offal yields from this study indicate that the Plains zebra has the potential to be used and distributed as an alternative protein source.

An Origanum majorana Leaf Diet Influences Myogenin Gene Expression, Performance, and Carcass Characteristics in Lambs.

Myogenin is a protein in the myogenic regulatory factor family that plays an important role in determining carcass and meat traits and is vital for the growth and development of livestock muscles. The objective of this study was to determine the impact of Origanum majorana leaf (MOL) on the myogenin gene expression of lambs. Twenty-four male Kermani lambs were used in a completely randomized design using two experimental groups (0% Origanum majorana L. = MOL0 and 4% Origanum majorana L. = MOL4). Final weight, average daily gain, hot and cold carcass weight, feed conversion ratio, empty body weight, hot and cold dressing percentage, the weight of the shoulder, loin, leg, and lean meat, and the lean/bone ratio were measured. A standard kit was used for extracting total RNA from the loin, leg, and shoulder muscles of the lambs’ tissues. The cDNA was synthesized, a real-time PCR was performed, and the obtained data were analyzed. The results of this study showed that the effect of MOL4 on dry matter intake is not significant. The MOL4 diet increased final weight by 8.22%, average daily gain by 28.57%, hot carcass weight by 11.38%, cold carcass weight by 13.43%, feed conversion ratio by 31.03%, empty body weight by 9.38%, hot dressing percentage by 2.92%, cold dressing percentage by 3.75%, shoulder weight by 56.70%, loin weight by 8.98%, leg weight by 10.90%, lean meat weight by 14.62%, and the lean/bone ratio by 2.85% (p < 0.05) compared to the MOL0. Along with adding MOL4 in the lambs’ diets, in comparison with MOL0, there was higher expression of myogenin in the loin (3.5 times), leg (3.9 times), and shoulder (3.6 times) muscles of the lambs. Due to the fact that adding Origanum majorana to the diet of the lambs enhanced the expression of the myogenin gene in the loin, leg, and shoulder muscles and increased parameters related to growth, it can be used to improve the parameters related to growth and to increase myogenin gene expression in the muscle of lambs.

Low- and high-protein diets supplemented up to the fourth limiting amino acid for genetic lines of grower-finisher pigs

The protein contents in diets for grower-finisher pigs reflect directly on the pig industry, also allowing to verify the responses of modern genotypes according to the protein feeding regimen. Therefore, this study was conducted to assess low- and high-protein diets and 2 genetic lines on growth performance, plasma urea concentration (PUC), apparent digestible energy and nutrient digestibility, N balance, carcass traits and meat quality in grower-finisher pigs. In Exp. I, a total of 120 pigs (31.5 ± 5.2 kg BW) were assigned to a 2 × 2 factorial arrangement of treatments, 2 genetic lines (LI7600 and AGPIC 337) and 2 protein diets (low-protein, LP, and high-protein, HP), with 10 replicate pens per treatment and 3 pigs per pen in a randomized block design. In Exp. II, 24 entire male pigs (27.4 ± 2.9 kg BW) housed individually in metabolic cages were used in the same design as Exp. I with 6 replicates though. In Exp. I, pigs fed HP diet showed (P ≤ 0.05) greater ADG and ADFI than those fed LP diet. However, gain to feed ratio was lower (P < 0.05) in pigs fed LP diet during grower I, finisher II, and total period. Plasma urea concentration was lower (P < 0.05) in pigs fed LP diet during grower I and II and finisher I. Pigs fed HP diet had greater (P < 0.01) N intake, N absorbed, N retained, total N excreted and urine N than those fed LP diet. Fecal N was greater in AGPIC 337 pigs than in LI7600 pigs (P = 0.009). Pigs fed HP diet had greater (P ≤ 0.05) cold carcass weight, lean meat, and initial pH in L. dorsi when compared to pigs fed LP diet. However, meat color, marbling degree, drip loss, and cooking loss were lower (P ≤ 0.05) in pigs fed HP diet. LI7600 pigs showed greater (P ≤ 0.05) backfat thickness than AGPIC 337 pigs. However, lower lean meat and a* were observed (P ≤ 0.05) in LI7600 pigs. In Exp. II, LI7600 pigs showed greater (P = 0.048) ADC of gross energy and digestible energy than AGPIC 337 pigs. In conclusion, pigs fed HP diet showed optimal growth performance, meat attributes, and apparent digestibility of CP. However, HP diet did not reduce the N excretion with changes in PUC, and low CP diet without Val-and Ile-supplementation can compromise pig production performance. Furthermore, AGPIC 337 pigs showed optimal results on meat attributes compared with LI7600 pigs, but lower apparent energy digestibility.

Effects of castration age on growth performance, carcass characteristics and economic efficacy in Hanwoo steers

ABSTRACT This study was conducted to investigate the effects of castration age on the growth performance, carcass characteristics, and economic efficacy of Hanwoo steers. There is an increasing interest in extending castration age to enhance the yield of desirable traits in beef, e.g. carcass weight and longissimus muscle area. The calves were divided into four groups based on their age at castration. Body length at 12 months increased with increasing castration age (p < 0.05). Average daily gain and cold carcass weight were higher in the group castrated at 11–12 months than in the group castrated at <10 months (p < 0.05). Marbling scores were higher in the groups castrated at <10 months of age than in the groups castrated at >11 months (p < 0.05). The present results suggest that the most appropriate castration age is below 12 months in Hanwoo cattle.

Application of multivariate discriminant analysis for differentiation between Saudi sheep (Ovis aries) breeds based on physical and histochemical meat characteristics.

The multivariate discriminant (MVD) analysis was a successful statistical tool with a discriminatory capacity for tracing sheep breeds based on meat characteristics. Thus, this study aimed to identify three Saudi sheep breeds based on the physical and histochemical aspects of meat using MVD analysis. Eight male lambs from each breed, Najdi, Neami, and Harri, were selected randomly at 90 days of age and allocated into three groups for breeding in a completely randomized design. The feeding and rearing management were similar for an experimental period of 90 days. The experimental diet consisted of a concentrated mixture with identical amounts of calories and nitrogen. Fifty-one meat characteristics were measured in the preliminary MVD, representing hot and cold carcass weight, meat cuts and quality measures, body component weights, fat deposit weights, and histochemical characteristics. Out of the total meat characteristics measured, only 19 characteristics had significant discriminant power. The most powerful characteristics were temperature, empty intestinal weight, pH24, external carcass length, heart weight, and L1, based on partial R-square and Wilks' lambda values. The phenotypic associations between the characteristics had strong associations. The obtained principal components efficiently classified the eight individuals of each breed into distinct groups using robust discriminant characteristics. This method allowed us to determine the breed of sheep carcasses and cuts by considering the physical characteristics of the meat. Therefore, butchers and consumers should use scientific techniques for assigning carcasses and meat to their sheep breed after slaughtering.

Fattening performance, nutrient digestibility, and carcass traits of two fat-tailed sheep breeds.

Fat-tailed sheep breeds are the most widespread types of sheep in the Middle East. They are hardy and have acceptable growth and carcass traits. The purpose of this study is to compare the fattening performance, nutrient digestibility, and carcass characteristics of two fat-tailed sheep breeds, Awassi and Najdi. Thirty single-born Awassi and Najdi male lambs (15 lambs per breed) were examined for fattening and carcass characteristics. The study lasted 70days (10days adaptation period and 60days for collecting the data). Feed consumption was monitored daily, and the body weight of lambs was recorded upon arrival to the trial area and biweekly afterward. Lambs were slaughtered at the end of the study to assess carcass and meat quality characteristics. Nitrogen intake and retained nitrogen were higher (P < 0.05) for Najdi lambs. The digestibility of nutrients was comparable between the two genetic groups. Initial body weight, final body weight, average daily gain, and dry matter intake were not affected (P > 0.05) by the lamb's breed. Furthermore, the feed-to-gain ratio, hot and cold carcass weights, and dressing percentage were not affected by breed type (P > 0.05). Breed type has no influence on the shoulder, loin, and rack percentages of the lamb. Moreover, meat quality traits were not affected by the lamb's breed (P > 0.05). In the dissected leg cut, no differences in the leg component were found among the two breed types (P > 0.05). Results of this study reveal that nitrogen intake and retained nitrogen were higher for Najdi lambs, but this was not reflected in fattening performance and carcass traits.

12 Growth Performance, Physiology, and Carcass Merit of Supplementing Brahman Steers with Zilpaterol Hydrochloride Under Heat Stress Conditions

Abstract Supplementation with a β- adrenergic agonist (β-AA) for 21 days in Brahman steers under heat stress conditions (HS) was evaluated with respect to feedlot performance and carcass merit. Twenty-four Brahman steers (kg = 338 ± 39) were housed in two controlled environment chambers with one of two environmental (ENV) conditions 1) heat stress (HS; THI = 73 to 85) and 2) thermoneutral (TN; THI = 68) with either Zilpaterol hydrochloride (ZL) or soymeal supplementation (CN) using a randomly assigned in a 2 x 2 factorial design (n=6/group). Daily data were collected for dry matter intake, water intake, respiratory rate (RR), and rectal temperature (RT). At the end of 21 d period, total weight gain was used to calculate average daily gain (ADG) and gain to feed. Blood samples were collected from the jugular vein on days -7, 3, 10, and 21 for cortisol analysis, and biological impedance analysis (BIA) was determined on days 3, 10, and 21 on each animal. Steers were harvested at 544 kg on average post supplementation/environment conditions, and carcass merit was determined. There were no differences (P &amp;gt; 0.05) in feedlot performance. Brahmans exposed to heat stress had greater RR during the heat stress periods of the experiment, regardless of supplementation. Environment and day interactions (P &amp;lt; 0.04) were observed for RT, HS steers had a greater RT on d 8 but similar RT on d 15 and 19. Stressed steers with ZL had higher RT (P &amp;lt; 0.05) than TN/CN steers on d 11. There was no interaction (P &amp;gt; 0.05) between environmental conditions and CN and ZH supplementation for cortisol concentrations. Regardless of environmental treatment or supplementation, no difference (P &amp;gt; 0.05) was associated with BIA characteristics. There were no differences (P &amp;gt; 0.05) for hot carcass weight, cold carcass weight, USDA yield grade, 12th rib loin eye area, marbling score, KPH percentage, and 12th rib fat thickness between groups. Twelfth-rib loin eye area lean color from HS/CN had higher lightness (L*) (P &amp;lt; 0.05) than TN/CN steers. HS/CN steers present a similar (L*) to ZL in TN and HS conditions. Redness-greenness (a*) was greater (P = 0.01) in carcasses from HS steers with or without ZL than TN/ZL but similar to TN/CN. Steers exposed to HS and CN had a higher (P = 0.02) change of 12th rib lean color from yellow to blue (b*) than TN steers with CN and ZL. Supplementation with β-AA did not negatively impact growth, carcass performance, or carcass merit in heat-stressed steers.

Acacia mearnsii tannin extract and α-tocopherol supplementation in lamb diet: Effects on growth performance, serum lipid peroxidation and meat quality

This study investigated the effects of supplementing lamb diets with plant bioactive compounds α-tocopherol, tannin and the association of both on lamb growth, blood and meat characteristics. Forty male lambs were housed in individual pens and assigned to four treatment groups (10 animals/group), where, for 62 d, they were fed: 1) a basal diet with soybean hulls, soybean meal and corn (Control); 2) the Control diet containing α-tocopherol (Tocopherol); 3) the Control diet containing Acacia mearnsii tannin extract (Tannin); and 4) The Control diet containing A. mearnsii extract and α-tocopherol (Tannin + tocopherol). The Tannin and Tannin + tocopherol treatments resulted in lower cold carcass weight. The concentration of α-tocopherol in the muscle was higher in Tocopherol and Tannin + tocopherol treatments. Meat lipid oxidation, after 7 days of storage, was lower (P ≤ 0.05) in lambs fed Tocopherol and Tannin + tocopherol than in the Tannin treatment, while the treatments with Tannin experienced a trend of reduced serum lipid peroxidation. Tannin diets modified the meat fatty acid profile, with an increase in C17:0 and in the PUFA/MUFA ratio and a decrease in the enzymatic Δ9-desaturase activity (C16 and C18) and in the MUFA/SFA ratio, in addition to promoting a increasing in the sum of PUFAs. Lamb supplementation with α-tocopherol and A. mearnsii tannin are alternatives capable of improving meat quality and reducing serum lipid peroxidation.

Comportamiento productivo y caracteristicas de la canal de ovinos en finalización alimentados con biomasa de Quercus rugosa tratada con urea

The objective was to evaluate the effect of biomass of Quercus rugosa (BQR) treated with urea (0, 2 and 4% urea) on the growth performance and carcass characteristics of feedlot lamb ram. The treatments were randomly assigned to 36 lamb ram (30 ± 0.5 kg): Control, BQR treated with 0, 2 or 4% urea. DM intake, average daily gain (ADG) and final weight (FW) were higher (P <0.05) in lambs fed BQR treatments treated with 0, 2 and 4% urea. Hot and cold carcass weight (HCW and CCW) and yield (CY) were higher (P < 0.05) in carcasses from lambs fed BQR treated with 4% urea. The proportion of muscle increased (P < 0.05), while the proportion of fat decreased (P < 0.05) in the BQR treated with 2 and 4% urea. It is concluded that the inclusion of BQR treated with 4% urea improves FW, ADG, DMI, HCW, CCW, CY, and increases the proportion of muscle and reduces carcass fat.

The effects of weather on beef carcass and growth traits

To predict the impact of climate change on our beef animals and systems, we need a better understanding of how beef cattle traits are affected by varying weather and frequency of extreme events. We analysed the effect of minimum and maximum temperatures and average daily precipitation on a range of important carcass traits, including age at slaughter, cold carcass weight, carcass growth rate and conformation and fat score (N = >1.6 million), as well as calf 200-day live weight and growth rate (N = >270 000), using data from abattoirs across Britain (carcass traits) and calves in Scottish suckler beef herds (live weights and growth). Animals which experienced higher daily maximum and minimum temperatures had slower carcass and calf growth rates. Increased precipitation also led to poorer cold carcass weights, conformation scores, calf 200-day weights and calf growth. We also analysed the effect of frequency of extreme weather events, including heatwaves, cold waves, and dry and wet days. The frequency of heatwaves, dry and wet days were shown to have significant negative effects on almost all traits considered, for example, predicting that an increase in the frequency of heatwaves by 1 day per 100 days of life would reduce cold carcass weights by about 200 g and increase age at slaughter by about 3 days. Results show that varying weather and frequency of extreme weather, across the lifetime of a beef animal, influences traits which affect the potential profit for a beef farmer. These effects may be due to several factors, including direct effects on the animal, as well as feed availability and management decisions made by the farmer. However, there is potential to mitigate negative effects through a range of animal management strategies.

Effects of slaughter age and gender on carcase characteristics and meat quality of native Mexican Turkey (M. g. gallopavo) reared under an extensive production system

The study aimed to investigate the effects of slaughter age and gender on carcase characteristics and meat quality of native Mexican turkeys raised under an extensive production system. Forty-five native turkeys (36 males and 9 females) were used. They were sacrificed at 24, 32, and 40 weeks of age. Slaughter age significantly affected slaughter weight (SW), hot carcase weight (HCW) and cold carcase weight (CCW). Also, dressing percentages, non-carcase components, internal organs, abdominal fat, and most carcase parts and proportions were affected. Gender significantly affected SW, HCW and CCW, non-carcase components, internal organs, and carcase parts weights. Regarding the physical properties of breast and leg meat, pH values and colour parameters taken at 45 min and 24 h post-mortem, as well as the water-holding capacity (WHC), cooking (CL), and drip loss (DL), were significantly affected by slaughter age, except CL in leg meat. Meanwhile, gender influenced L*45min, b*24h, the pH24h values, and CL in breast meat. Concerning the chemical composition of the meat, slaughter age had a significant effect on the ether extract (EE) content of breast meat and on dry matter (DM), crude protein (CP), EE, ash, and energy contents of leg meat. Gender significantly affected the DM, CP, and energy contents of breast meat and DM, EE, and energy contents of leg meat. These results indicate that the carcase weight and yield, and its components, as well as meat quality, were better in older male turkeys than in adult females. HIGHLIGHTS Slaughter age and gender significantly influence carcase yield and composition and as well as meat quality in native Mexican turkeys raised under extensive traditional conditions. It is recommended that native turkeys be slaughtered at around 40 weeks to obtain more acceptable carcase yields and meat of better nutritional value. The native Mexican turkey is a viable poultry resource for ecological production systems.