Influence of detoxified neem seed cake on diet digestibility, body weight change, hormonal profiles, immune response and testicular gene expression in male sheep

Abstract

The present study was conducted to find out the effect of supplementing defatted and detoxified neem (Azadirachta indica) seed cake as a partial replacement of soybean meal (SBM) in the diet of growing lambs. Male lambs of uniform body weight (8.31±0.32kg) were randomly allotted to three groups such as control (diet containing SBM) and two test diets with defatted and detoxified neem cake (DNC) at two levels (34g and 68g per kg of diet) replacing 25% and 50% nitrogen of SBM (DNC-25 and DNC-50). The respective diets (concentrate mixtures along with finger millet (Eleucine corocana) straw) were fed individually to lambs for a period of 140 days. The repeated measure ANOVA indicated that lambs on DNC treatments grew on par with control across all the periods and no interaction was observed. The difference in the dry matter intake was not found to be significant (P>0.05) in any of the three study groups. Similarly apparent nutrient digestibility, nitrogen balance, rumen and hormonal profiles did not differ (P>0.05) across the groups. Humoral and cell mediated immune response measured in terms of antibody titre and lymphocyte proliferation assay was also the same (P>0.05) across the groups. The relative gene expression of IGF-I and LHR transcripts in testes tissue was positively influenced (P<0.05) in DNC-50 treatment (3–4 fold increase) as compared to control and DNC-25. No histopathological changes were observed in vital organs of sheep fed DNC diets compared to control. It can be concluded that based on the studied parameters, DNC can replace 50% of SBM nitrogen with 3–4 fold increase in gene expression in testes tissue.