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-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.

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________________________________________________________________________________ AbstractEggs from a meat-type breeder flock at 29 and 35 weeks of age were used in two trials to investigate the effects of in ovo feeding of carbohydrates (CHO) and high incubation temperature (37.5 vs. 38.5 °C (HIT)) during days 16 to 21 of incubation on hatchability traits, chick weight at hatch as an absolute value or as a percentage of egg weight (CWTP), hatching time, glycogen concentration in the liver and pectoral muscle, and glycogen index of hatched chicks. The treatments were a non-injected control, a positive control where saline was injected, or saline with a CHO mixture at 50, 100, 150, 200 and 250 mg/egg. The CHO mixture was maltose, sucrose and dextrin in a proportion of 1 : 1 : 8 by weight. As a result of this study, in ovo feeding of CHO increased CWTP without altering hatchability traits. Hatched chicks from eggs injected with 250 mg CHO/egg had a higher liver glycogen content and glycogen index than those of the control treatments. The high incubation temperature reduced chick weight, hatching time, liver glycogen and glycogen index of the hatched chicks. In ovo feeding of 100 and above mg CHO/egg overcame the negative effects of HIT. Hatched chicks from older hens had a lower concentration of liver glycogen and glycogen index than those of younger hens. It was concluded that in ovo feeding of CHO improved the weight and glycogen index of hatched chicks and those of the HIT treatment, and older hens negatively affected the glycogen index of hatched chicks. ________________________________________________________________________________

The effects of in ovo amino acid administration on hatchability traits and post-hatch performance were studied using eggs from a meat-type breeder flock (Ross) at 38 weeks of age. On day 15 of incubation, five treatments were applied, consisting of six replicates with 16 eggs per replicate. The treatments consisted of a non-injected negative control; a positive control in which saline was injected; and three treatments with saline, containing 23.72 mg lysine, glutamine, glycine and proline (AA1); 23.60 mg arginine, glutamine, glycine and proline (AA2); and 28.76 mg lysine, arginine, glutamine, glycine and proline (AA3). The hatchability traits were incubation period, chick weight at hatch as an absolute value (CWT) and chick weight at hatch as a percentage of egg weight (CWTP), and the post-hatch performance traits were body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR). Measurements on the chickens were taken during the starter (1 -21 days of age), finisher (22 -35 days of age) and entire (1 -35 days of age) experimental periods. In ovo amino acid treatments improved CWTP without affecting hatchability traits, and increased FI without altering the FCR of chickens during the entire experimental period. Chickens of the in ovo AA1 treatment had a higher FI than those of the control treatments during the finisher period. In ovo AA2 treatment increased CWT and BWG of the chickens during the starter period and entire experimental period and FI during the finisher period, when compared with those of the control treatments. In ovo AA2 treatment resulted in a longer period of incubation than those of other treatments. It was concluded that in ovo amino acid treatment increased CWTP and FI of chickens without affecting hatchability traits and feed efficiency and in ovo of AA2 treatment increased the incubation period, CWT and BWG when compared with those of control treatments during the entire experimental period. ______________________________________________________________________________________