Influence of Nigella sativa seeds, Rosmarinus officinalis leaves and their combination on growth performance, immune response and rumen metabolism in Dorper lambs.

The objective of this study was to determine the effects of dietary supplementation of Nigella sativa L. seeds, Rosmarinus officinalis L. leaves and their combination on rumen metabolism, nutrient intake and digestibility, growth performance, immune response and blood metabolites in Dorper lambs. Twenty-four entire male Dorper lambs (18.68 ± 0.6 kg, 4-5 months old) were randomly assigned to a concentrate mixture containing on a dry matter basis either, no supplement (control, T1), 1% R. officinalis leaves (T2), 1% N. sativa seeds (T3) or 1% R. officinalis leaves +1% N. sativa seeds (T4). The lambs had ad libitum access to urea-treated rice straw (UTRS) and were raised for 90 days. Supplemented lambs had greater (P < 0.05) intake of DM and UTRS than the control lambs. The T4 lambs had lower (P < 0.05) nutrient digestibility than those fed other treatments. Total and daily weight gain was greater (P < 0.05) in T2 lambs than those fed other diets. The T3 and T4 lambs had greater (P < 0.05) ruminal pH than the T1 and T2 lambs. Supplemented lambs had lower (P < 0.05) ruminal total volatile fatty acids, acetate, propionate, NH3-N and C18:0 than the control lambs. The T4 lambs had lower (P < 0.05) population of Fibrobacter succinogenes, Ruminococcus albus, methanogens and total protozoa compared with those fed other diets. Supplemented lambs had lower (P < 0.05) neutrophils, basophils and serum urea and greater (P < 0.05) serum IgA and IgG compared with the control lambs. The current results emphasised the variation in the efficacy of medicinal plants in ruminant nutrition.

Carcass traits, fatty acid composition, gene expression, oxidative stability and quality attributes of different muscles in Dorper lambs fed Nigella sativa seeds, Rosmarinus officinalis leaves and their combination.

OBJECTIVE: This study examined the influence of dietary supplementation of Nigella sativa seeds, Rosmarinus officinalis leaves and their combination on carcass attributes, fatty acid (FA) composition, gene expression, lipid oxidation and physicochemical properties of longissimus dorsi (LD), semitendinosus (ST), and supraspinatus (SS) muscles in Dorper lambs. METHODS: Twenty-four Dorper lambs (18.68±0.6 kg, 4 to 5 months old) were randomly assigned to a concentrate mixture containing either, no supplement (control, T1), 1% Rosmarinus officinalis leaves (T2), 1% Nigella sativa seeds (T3), or 1% Rosmarinus officinalis leaves+1% Nigella sativa seeds (T4) on a dry matter basis. The lambs were fed the treatments with urea-treated rice straw for 90 days, slaughtered and the muscles were subjected to a 7 d postmortem chill storage. RESULTS: The T2 lambs had greater (p<0.05) slaughter and cold carcass weights than the control lambs. Dietary supplements did not affect (p>0.05) chill loss, dressing percentage, carcass composition, intramuscular fat and muscle pH in Dorper lambs. Meat from supplemented lambs had lower (p<0.05) cooking and drip losses, shear force, lightness, and lipid oxidation and greater (p<0.05) redness compared with the control meat. The impact of dietary supplements on muscle FA varied with muscle type. Diet had no effect (p>0.05) on the expression of stearoyl-CoA desaturase and lipoprotein lipase genes in LD and ST muscles in Dorper lambs. The T2 and T3 diets up regulated the expression of AMP-activated protein kinase alpha 2 gene in LD and ST muscles and up regulated the expression of sterol regulatory element-binding protein 1 in ST muscle in Dorper lambs. CONCLUSION: Dietary supplementation of Nigella sativa seeds and Rosmarinus officinalis leaves had beneficial effects on meat quality in Dorper lambs.