Growth performance, nutrient utilization, rumen fermentation, blood biochemistry, and carcass traits of lambs fed Atriplex nummularia L. hay-based diet supplemented with yeast or bacterial direct- fed microbial.

Direct fed microbial may enhance the utilization of halophyte forages leading to improved animal growth and productivity. This study was conducted to evaluate Atriplex hay-based diet supplemented with yeast (Saccharomyces cerevisiae; SC) or bacteria (Bacillus subtilis and Lactobacillus casei; BAC) on lamb growth performance, digestibility, rumen fermentation, and carcass characteristics. Fifteen Barki lambs (90 ± 7 days of age and 18.6 ± 0.41 kg SE body weight; BW) were randomly assigned to three treatments for 120 days as follows: Control (basal diet without supplementation), SC and BAC diets, the basal diet supplemented with SC or BAC at 2 g/head/day, respectively. All lambs had similar dry matter (DM) intake, while lambs fed SC or BAC dies had higher (P < 0.05) total gain and average daily gain than those fed the control diet. Supplementation of SC or BC increased (P < 0.05) the digestibility of DM, organic matter, and acid detergent fiber, tended to decrease (P < 0.05) the urine N excretion and enhanced the N balance compared to the control. Ruminal pH, acetate, total volatile fatty acids concentrations, and bacterial protein were increased (P < 0.05), while creatinine and urea concentrations were decreased (P < 0.05) by both additives. Compared to other diets, the BAC diet reduced (P < 0.05) triglycerides, total lipids, kidney fat, and eye muscle fat. In conclusion, both additives resulted in similar positive growth performance and feed utilization, while only the BAC additive had a beneficial advantage in reducing the fat content of the carcass.

Phenotypic and genetic parameters of productive traits in Rahmani and Romanov sheep and crossbreds.

Data of 651 lambs (68 Romanov, 49 Rahmani, 151 [♀1/2 Rahmani X ♂1/2 Romanov) and 383 (♀3/4 Rahmani and 1/4♂ Romanov]) were collected from Mehalet Mousa Farm, belonging to Animal Production Research Institute from the period of 2009 to 2016 to estimate phenotypic and genetic parameters. The traits studied were birth weight (BW), body weight at four week (BW4), body weight at eight weeks (BW8) and body weight at twelve weeks (BW12) or weaning weight. Least squares analysis of variance shows significance of the effects of breed groups, gender of lambs, birth type; month of birth and year of birth on all traits studied. Rahmani lambs had heavier BW, BW4, BW8 and BW12 while Romanov lambs had the lowest ones. The first generation (♀1/2 Rhamani X ♂1/2 Romanov) had heavier body weights than Romanov and the second generation (♀3/4 Rahmani X ♂1/4 Roamnov). Gender of lambs had highly significant effect on body weights. Males were significantly (p < 0.01) heavier than females for all traits studied. Least square means of BW, BW4, BW8 and BW12 for single lambs were 2.69, 10.43, 13.53 and 16.10 kg, respectively. Least square means of BW, BW4, BW8 and BW12 for twin lambs were 2.50, 9.37, 12.5 and 15.16 kg, respectively, while least square means of BW, BW4, BW8 and BW12 for triple lambs were 2.09, 7.86, 10.83 and 13.67 kg, respectively. Estimates of direct heritability measured by single trait animal model were 0.14, 0.23, 0.25 and 0.26 for BW, BW4, BW8 and BW12, respectively, and the corresponding measured by multi trait animal model were 0.17, 0.24, 0.32 and 0.36 for the same traits, respectively. All genetic and phenotypic correlations among different traits studied are positive and significant.