Neem (Azadirachta indica A. Juss syn. Melia azadirachta Linn.) seed cake boiled with 8 g caustic soda/kg cake in 2·51 of water for 30 min yielded a product which was palatable to cattle unlike untreated neem seed cake which is bitter, foul smelling and wholly unpalatable to cattle.
Two experiments were made on calves to compare the performance of two groups of animals; one group (control) fed on a standard concentrate mixture consisting of 33% groundnut cake, 34% maize and 33% wheat bran and the second group (experimental) on 50% alkali-treated neem seed cake, 33% groundnut cake and 17% maize, the roughage being the same in both the groups.
The results showed that the dry-matter intake/100 kg body weight of the animals did not differ significantly (P > 0·05) between the two groups but digestibility of dry matter and total carbohydrates and the growth rate was significantly lower (P < 0·05) in the experimental group. The digestibility of crude protein and ether extract and the adjusted balances of nitrogen, calcium, phosphorus and sulphur remained similar (P > 0·05) in the two groups. The reduction of the growth rate in the experimental group could be accounted for by the lower total digestible nutrients (TDN) intake and there was no difference (P > 0·05) in the serum icteric index, blood inorganic phosphorus and serum alkaline phosphatase activity in the two groups.
It is concluded that alkali-treated neem seed cake has great potential as a cattle feed and alkali treatment removes either completely or very largely the toxic principles present in neem seed cake.