Growth rate of carcass, non-carcass and chemical components of restricted fed and realimented growing lambs (original) (raw)
Related papers
Revista Brasileira de Zootecnia, 2013
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.
Effect of different feed restriction regimens on lamb performance and carcass traits
Revista Brasileira de Zootecnia, 2015
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.
Annales de Zootechnie, 1984
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.
Life
A total of 75 male Awassi (mean BW 23.5 ± 2.0 kg; 3 months old) were used in an 84-day trial to investigate the effects of different feeding regimes on productive performance, carcass characteristics, and meat quality, and the fatty acid profile of growing lambs. Animals were randomly allocated into 3 groups of 25 lambs each. The dietary treatments were as follows: (1) whole barley grain (60%) plus alfalfa hay (40%; GB-AH; the basal diet); (2) a concentrate pelleted diet plus alfalfa hay (CP-AH); and (3) a complete pelleted diet (CPD). Feed intake was measured weekly, and all lambs were weighed every two weeks for an evaluation of the productive parameters. Blood samples were collected from all lambs for the measurement of biochemical and enzymatic variables. At the end of the experiment, 13 lambs from each treatment were slaughtered to evaluate the carcass characteristics, meat quality, and fatty acid composition. The final body weight, body weight gain, average daily gain, and fee...
The Effects of Supplementary Feeding of Lambs Grazing on Growth Rate and Carcass Characteristics
2012
This study aimed to establish optimal strategies to supplement the diet of fattening lambs on pasture exposed. Ration supplementation on pasture fattening lambs exposed, concentrated (PC), concentrates and hay (PCF) and respectively concentrated, hay and saponified fat (PCFG) led to significant improvement (p< 0.05) of major bioperformance materialized in growth final body weight up to 11.40 kg respectively in weight gain up to 67.8%. Positive effects of energy from the food supplement and changes in their rumen fermentation processes were reflected and browned on the indices but also the quality slaughterhouse carcasses. The highest yield at slaughter (53.82%) was achieved by lambs PCFG, due to better muscle development and also deposit a larger amount of internal fat and superficial. The lowest ratio meat/bones, considered the main commercial port of the casing cut (jigou, shoulder and loin) and the whole carcasses were recorded in the control group, leading to improved dietary...
TURKISH JOURNAL OF VETERINARY AND ANIMAL SCIENCES
Forty-eight Najdi male lambs weighing 33.1 ± 0.06 kg and approximately 4.5 months old were divided into three groups (16 lambs in each) to study the impact of compensatory growth on performance, carcass traits, fat deposition, tissue distribution, and lean chemical composition. The control group was fed ad libitum throughout the entire 12 weeks of the trial period. The other two groups were feed-restricted by 20% and 40% of the ad libitum group intake. Lambs in restricted treatments were feed-restricted for 3 weeks followed by 4 weeks of ad libitum feeding (compensatory) and then 2 weeks of feed restriction followed by 3 weeks ad libitum. No significant differences were detected among the three groups in overall average daily gain (g/day). During the two compensatory phases, the 40% group was more efficient (P < 0.05) in converting feed to gain, followed by the 20% group and finally by the 0% group. In general, feed restriction regimes did not affect (P > 0.05) carcass traits, fat deposition, meat properties, and chemical composition. It is concluded that feed restriction up to 40% can be an important tool to improve the growth efficiency and reduce the cost of meat production from growing Najdi lambs.
Journal of animal science, 1997
Eighty-eight early-weaned Hampshire x Targhee crossbred lambs (initial BW 23 +/- 3.9 kg) were used in a 2 x 2 factorial design experiment to determine the effects of DM and CP intake on lamb performance and weight and accretion rates of visceral organs during two periods of growth, divided at 36 kg live weight. There were 10 lambs per replicate and two replicate pens per treatment. Dry matter intake was 100 or 85% of ad libitum, and protein intake was 100 (normal) or 125% (high) of the calculated NRC (1985) requirement. Over both periods, lambs allowed ad libitum access to feed had greater (P < .05) ADG, rumen/reticulum, large intestine, and liver weights and faster accretion rates than lambs fed at 85% of ad libitum; however, there were no differences (P = .87) in feed efficiency. For the total trial, lambs fed high protein had greater (P < .01) DMI, ADG, liver and kidney weight and accretion rates, and increased (P < .01) feed efficiency during period 1 compared with lamb...
Journal of the Indonesian Tropical Animal Agriculture, 2022
A study was conducted to investigate the growth rate and carcass characteristics of lambs under different feeding levels. Twenty one lambs (3 months old) were allocated into 3 treatments of feeding levels, namely 4% of body weight (BW) (T1), 5.5% of BW (T2) and provided ad libitum (T3). The diet contained 13.74% of CP and 61.79% of TDN. The lambs were raised to reach 25 kg BW, before being slaughtered. The parameters observed were dry matter intake (DMI), dry matter digestibility (DMD), body weight gain (BWG), feed conversion ratio (FCR), carcass production, meat-bone ratio (MBR), fat distribution, chemical composition of meat and fatty acids profile. The data obtained were analyzed by analysis of variance and continued by Duncan's multi-range test if there was any significant difference among the treatments. The results showed that the average of DMD was 59.71% (P>0.05). The lambs fed T3 had the highest BWG (203 g/day), the lowest FCR (6.8) and the shortest rearing time (67 days) (P<0.01). The average of carcass percentage was 46.36% and meat production was 6,931 g (P>0.05). The lambs of T3 had the heaviest carcass fat (2,698 g), the lightest carcass bone (1,985 g), the highest MBR (3.6), and the highest PUFA to SFA ratio (0.55). It can be concluded that the higher the feeding level resulted in the higher growth rate, the lower feed conversion ratio, higher meat-bone ratio and higher carcass fat production, lower feed conversion ratio and the shorter rearing time; but did not affect the meat quality.
Effects of dietary energy level on the performance and carcass characteristics of lambs
Semina: Ciências Agrárias, 2020
The objective of this study was to evaluate the influence of ration energy levels on the performance and carcass characteristics of confined lambs. Four energy levels were evaluated: 2.00; 2.28; 2.54, and 2.80 Mcal of ME kg-1DM, with the last content being recommended by the National Research Council [NRC] (2007) for daily weight gains of 300 g. Twenty-four crossbred Ile de France ram lambs (six per treatment) at 240.0 ± 9.6 days of age and 26.6 ± 3.8 kg body weight, fed with isoprotein diets (158 g kg-1, CP) were used. The confinement lasted 57 days. Final body weight, cold carcass weight, and cold carcass yield were linearly and positively influenced by diet energy content. Food intake, average daily weight gain, and feed conversion were quadratically influenced by energy level, where the highest averages were observed under diets containing between 2.54 and 2.80 Mcal. In percentage terms, the main carcass cuts (leg and shoulder) were not influenced by diet energy level. In terms ...
Carcass tissue composition in light lambs: Influence of feeding system and prediction equations
Livestock Science, 2009
Fourty-eight Churra Tensina single male lambs were used to evaluate the effect of different feeding systems on carcass composition and predict the carcass tissue composition from joint composition and carcass measurements. Four treatments were studied: GR, unweaned lambs continuously grazing with ewes; GR + S, the same as the previous group, but lambs had free access to concentrate; DRL-GRE, lambs remained indoors with free access to concentrate and ewes grazed for 8 h/day, thereafter remaining with lambs; and DRL, lambs and ewes were kept in confinement, they had free access to concentrate and dry unifeed respectively. In the DRL-GRE and DRL groups lambs were weaned when 45 days old. Lambs were slaughtered at 22-24 kg live weight. Commercial joints from the half left carcass were obtained, recorded and dissected to determine carcass tissue composition. The feeding system had an effect on the proportion of the carcass tissue composition. GR treatment showed higher muscle (M) (p b 0.05) and bone (B) (p b 0.001) percentages, and a lower total fat (F) percentage (p b 0.001) than the rest of treatments. Hence it revealed higher M/F (p b 0.01) and lower M/B (p b 0.05) and subcutaneous fat/intermuscular fat ratios (SF/IF; p b 0.001). Carcass composition predictions were more accurate for grams than for percentages. In predictions from joint composition, pelvic limb was the most accurate joint for grams (R 2 = 0.84, R 2 = 0.68, and R 2 = 0.77 for muscle, bone, and fat, respectively) as well as for percentage (R 2 = 0.65, R 2 = 0.56, and R 2 = 0.73 for muscle, bone, and fat, respectively). Predictions from carcass measurements were greater in muscle and fat grams (R 2 = 0.87 and R 2 = 0.86 for muscle and fat, respectively) than in percentage (R 2 = 0.58 and R 2 = 0.73 for muscle and fat, respectively). Equations to predict carcass tissue that include carcass measurements are a simple method to assess accurately saleable muscle yield from different lamb feeding systems without involving carcass damage.