Interaction of growth hormone with androgen/estrogen on beef carcass characteristics, and chemical, physical and palatability properties of longissimus muscle of steers

The objectives of this study were to investigate the effects of recombinant bovine somatotropin (bST), Revalor and the combination of the two on beef carcass characteristics, quality and physical, chemical and palatability attributes of bovine longissimus (loin eye) muscle. Crossbred steers (n = 20) were blocked by body weight and allotted in a 2 x 2 factorial arrangement of treatments: control, Revalor-S°ler (Trenbolone acetate 120 mg+estraiol 24 mg) implanted in ear on day 1 and 97, bST (160 mg/wk), and Revalor-S°ler + bST and fed for 140 days. Loin eye was removed from left side, cut into 2.4 cm steaks and postmortem aged for 13 days. Revalor treatment increased (p \u3c.05) body, hot carcass, longissimus and semitendinosus weights and loin eye area; however, bST had no effect (p \u3c.05) on these variables. Backfat, KPH fat %, and dressing percentage were not affected (p \u3c.05) by either Revalor or bST. Carcass composition was physically separated into lean, fat, and bone. Lean, fat, and bone were increased (p \u3c.05) by Revalor; however, bST had no effect (p \u3c.05) on lean, bone was increased (p \u3c.05), and fat was reduced by 14.8% (p \u3c.13). Revalor tended to reduce marbling, and yield and quality grades; however; bST reduced marbling and quality grade (p \u3c.05, and.15) and had no effect on yield grade. Revalor had no effects on meat color, pH, drip and cook losses and water holding capacity; however, bST reduced cook losses (p \u3c.01). Revalor increased (p \u3c.05) protein, reduced (p \u3c.05) fat and had no effect on moisture; however, bST had no effect on these variables. Revalor decreased (p \u3c.05) total collagen and increased (p \u3c.26) soluble collagen. bST increased total collagen (p \u3c.01) and had no effects on soluble collagen. Revalor decreased (p \u3c.05) initial tenderness and myofibril fragmentation index (MFI), increased (p \u3c.05) shear force, and had no effects on juiciness and flavor intensity. Both bST had no effect on sensory attributes, shear force, and MFI. bST and Revalor had no effects (p \u3c.05) on fiber percentages. The percentage of intermediate fiber was increased and the percentage white fiber was decreased by either Revalor or bST. Revalor and bST had an additive effect for all of the measurements; however, there were interactions between Revalor and bST on semitendinosus weight (p \u3c.05), quality grade (p \u3c.08) and degree of marbling (p \u3c.04)

Betaine and nano-emulsified vegetable oil supplementation for improving carcass and meat quality characteristics of broiler chickens under heat stress conditions

IntroductionThis research aimed to examine the effects of water-added betaine (BET) and/or nano-emulsified vegetable oil (MAGO) on carcass and meat quality characteristics of broilers raised under thermoneutral (TN) and heat stress (HS) conditions.MethodsOn day 21, 640 birds (Ross 308) were randomly assigned to one of two thermal conditions (thermoneutral 22 ± 1°C and heat stress 32 ± 1°C) each containing four treatment groups: Control, BET, MAGO, and a mixture of both (BETMAGO) in a 2 × 4 factorial arrangement (eight groups). Each group has eight replicates, with ten birds each. The birds' carcass and meat quality characteristics were evaluated at 35 days.Results and discussionThe dressing percentage, breast, leg, wing, heart, initial pH, color change, cooking loss (CL), water-holding capacity (WHC), shear force (SF), and texture profile with exception of springiness significantly affected by the treatments. The results showed that HS had negative effects on carcass weight and relative weights of the breast, spleen, and heart. Moreover, HS increased dressing percentage, wing, initial pH, final core temperature, initial lightness, WHC, and hardness. Significant differences in interactions between treatments and temperature were observed in the spleen, WHC, and SF.ConclusionWater supplemented with BET effectively improved carcass dressing percentage, breast weight, and meat quality in terms of water-holding capacity and tenderness under HS conditions. More studies on the use of BET and/or MAGO at different levels were recommended

Interaction of growth hormone with androgen/estrogen on beef carcass characteristics, and chemical, physical and palatability properties of longissimus muscle of steers

The objectives of this study were to investigate the effects of recombinant bovine somatotropin (bST), Revalor and the combination of the two on beef carcass characteristics, quality and physical, chemical and palatability attributes of bovine longissimus (loin eye) muscle. Crossbred steers (n = 20) were blocked by body weight and allotted in a 2 x 2 factorial arrangement of treatments: control, Revalor-S°ler (Trenbolone acetate 120 mg+estraiol 24 mg) implanted in ear on day 1 and 97, bST (160 mg/wk), and Revalor-S°ler + bST and fed for 140 days. Loin eye was removed from left side, cut into 2.4 cm steaks and postmortem aged for 13 days. Revalor treatment increased (p <.05) body, hot carcass, longissimus and semitendinosus weights and loin eye area; however, bST had no effect (p <.05) on these variables. Backfat, KPH fat %, and dressing percentage were not affected (p <.05) by either Revalor or bST. Carcass composition was physically separated into lean, fat, and bone. Lean, fat, and bone were increased (p <.05) by Revalor; however, bST had no effect (p <.05) on lean, bone was increased (p <.05), and fat was reduced by 14.8% (p <.13). Revalor tended to reduce marbling, and yield and quality grades; however; bST reduced marbling and quality grade (p <.05, and.15) and had no effect on yield grade. Revalor had no effects on meat color, pH, drip and cook losses and water holding capacity; however, bST reduced cook losses (p <.01). Revalor increased (p <.05) protein, reduced (p <.05) fat and had no effect on moisture; however, bST had no effect on these variables. Revalor decreased (p <.05) total collagen and increased (p <.26) soluble collagen. bST increased total collagen (p <.01) and had no effects on soluble collagen. Revalor decreased (p <.05) initial tenderness and myofibril fragmentation index (MFI), increased (p <.05) shear force, and had no effects on juiciness and flavor intensity. Both bST had no effect on sensory attributes, shear force, and MFI. bST and Revalor had no effects (p <.05) on fiber percentages. The percentage of intermediate fiber was increased and the percentage white fiber was decreased by either Revalor or bST. Revalor and bST had an additive effect for all of the measurements; however, there were interactions between Revalor and bST on semitendinosus weight (p <.05), quality grade (p <.08) and degree of marbling (p <.04).</p

Postmortem injection of calcium chloride Improves camel meat tenderness

Twenty-four hours postmortem longissimus muscles of camel carcasses were injected to 0 (control), 200 and 300 mM food grade CaCl2 at 10% (wt/wt), vacuum- packaged and stored at 2ºC for 6 days. Drip loss, cooking loss, sarcomere length, and shear force were determined. At 6 days post-treatment, samples with CaCl2 had higher (P <0.05) drip loss compared to non-injected ones, however; cooking loss was not affected (P >0.05). Muscle sarcomere length was not significantly affected (P >0.05) but shear force values for treated samples were lower (P <0.05) than those of controls with ratios varied from 23.4% and 32.4% lower for the 200 and 300 mM injections, respectively, and therefore; calcium chloride injection is an effective method for improving camel meat tenderness.Corresponding Author: Dr. Ibraheem A. Al-Sheddy, Associate professor - Meat Science and Technology, Department of Food Science and Nutrition, College of Food and Agriculture Sciences, P.O. Box-2460, Riyadh -11451, Saudi Arabia. Email: [email protected]

Effect of different feed restriction regimens on lamb performance and carcass traits

Fifty Najdi ram lambs weighing an average of 38.1±0.5 kg were utilized in this study to determine the effects of feed restriction level with or without subsequent realimentation on lamb performance and carcass composition. Lambs were allotted randomly and equally into five groups. The groups were fed a control diet ad libitum; two groups fed 0.90 and 0.80 of ad libitum intake throughout the eight-week period of the trial (R), and two groups fed 0.90 and 0.80 of ad libitum intake for a six-week period followed by two weeks of realimentation (RR). All lambs were slaughtered after eight weeks of experimentation. Average daily gain (ADG) for the 0.90 and 0.80 ad libitum groups decreased by 7.6 and 26.9% during restriction, whereas the lambs during realimentation period had 35 and 30.5% faster ADG and 27.5 and 21.8% better feed:gain ratios than the control, respectively. At the end of the trial, final, empty and hot carcass weights and overall ADG of the 0.90 ad libitum RR group did not differ from control. Feeding performance values of the 0.80 ad libitum R group were the lowest among the treatments. The studied feed restriction regimens depressed the weights of empty stomach, tail fat, visceral fat, and subcutaneous fat; however, two weeks of realimentation were not enough to induce complete weight recovery in these tissues. The 0.90 ad libitum RR restriction routine can be adopted as a nutritional management practice for fattening Najdi lambs

Effect of restricted feeding and realimentation on feed performance and carcass characteristics of growing lambs

Forty Najdi ram lambs weighing 26.6±0.3 kg were utilized in this experiment to determine the effects of feed restriction followed by realimentation and body weight at the onset of feed restriction (30 and 36 kg body weights) on performance and carcass characteristics; feeding and restriction levels were ad libitum, 0.75 and 0.60 of the ad libitum intake. All lambs were slaughtered after 14 weeks of experimentation. The results showed that, during the feed restriction phase, average daily gain (ADG) and feed efficiency decreased as the level of restriction increased. During the realimentation phase, the 30 kg lambs gained weights and consumed dry matter (DM) similarly to the ad libitum group, whereas the ADG for the 36 kg lambs of both 0.75 and 0.60 ad libitum groups were 20 and 43.8% faster than the ad libitum group, respectively. At the end of the trial, final body weight and overall ADG of the realimented 30 kg groups were lower than ad libitum group, whereas the ADG of the 36 kg groups were not different compared with the ad libitum group. Although empty body, hot and cold carcass, empty stomach compartments, empty intestines and liver weights for the 36 kg groups were not affected by feed restriction followed by realimentation, weights of visceral fat depots, subcutaneous fat and tail fat decreased much more than those of the ad libitum group. Carcass composition of the realimented 0.75 and 0.60 ad libitum groups tended to have 5.1 and 8.8% less lean tissue than the ad libitum group when the restriction started at 30 kg, respectively. On the other hand, the realimented lambs of both 0.75 and 0.60 ad libitum groups tended to be 5.1 and 2.8% leaner than those of the ad libitum group when restriction started at 36 kg body weight, respectively. Feed restriction of up to 40% for a 5-week period followed by a 4-week period of refeeding in 36 kg lambs is economically feasible and does not offset production

The effects of the myostatin g+6723G&gt;A mutation on carcass and meat quality of lamb

This study evaluated the effects of the myostatin g + 6723G &gt; A mutation on carcass and meat quality traits of lamb (AA: n = 5; AG: n = 8; GG: n = 9). Dressing percentage was positively affected by the mutation with homozygotes for the mutation having the highest yield. Regarding carcass composition, there was a significant increase in the proportional weights of the loin and hindquarter muscles. Objective meat quality traits of the 'M. longissimus lumborum' (LL) and 'M. semimembranosus' (SM) were not significantly affected. For the SM, toughness (shear force and compression) tended to be lowest for homozygotes for the mutation. The myostatin g + 6723G &gt; A mutation did not affect sensory meat quality traits of grilled steaks for the LL, but resulted in a significant improvement in eating quality for the SM. Given the number of animals in this study, the robustness of the outcome of this study with regard to the effects on meat quality and its causes requires further investigation

Effects of Bovine Somatotropin and Revalor-S® on Growth Performance and Carcass Leanness in Beef Cattle

Twenty crossbred steers were used to evaluate bovine somatotropin (bST) and an anabolic steroid implant, Revalor-S® (REV), to improve growth and increase carcass leanness. During the first 70 days on feed, bST-treated steers tended to improve live weight gains, consume more feed, and numerically improve feed utilization for growth. The implanted steers grew faster and utilized feed better than steers not implanted with REV. The improvement in gain and feed utilization for growth was maintained throughout the feeding period for REV-implanted steers. At slaughter, REV steers had heavier carcasses which resulted in more pounds of muscle, bone, and fat. When adjusted for hot carcass weight, bST increased leanness of the carcass as evident by the increased weight of the semitendinosus muscle, more pounds of dissected lean, and fewer pounds of dissected fat. Thus, REV and bST can be used to improve growth performance and increase carcass leanness.</p