Effects of Dietary Neem (Azadirachta indica) Leaf Extract on the Performance of Laying Hens
AbstractThe effects of dietary neem (Azadirachta indica) leaf extract (NLE) on egg production, egg quality characteristics and blood indices of laying hens were investigated. Dry matter content of fresh neem leaves was determined and used to determine the quantity of the fresh leaves to be extracted to correspond with the required dietary dry matter inclusion. Three white maize-based experimental diets were made such that diet 1 (control) contained no NLE while diets 2 and 3 contained 2.5% and
5.0% NLE respectively, representing 2.5% and 5.0% dry leaf meal. Seventy-two laying hens were divided into 3 groups of 24 birds each and each group randomly assigned to one of the diets and fed for 8 weeks. Average daily feed intakes of the birds (101.3g, 104.8 g and 104.5 g) were not affected by the treatments (P> 0.05). The groups on NLE diets lost weight. At 5.0% dietary level, NLE significantly (P< 0.05) depressed hen-day egg production but increased egg weight. Feed conversion
ratio and egg quality indices were not affected by the treatments (P> 0.05). The NLE had limited effect on egg yolk colour. The weights of the internal organs were not affected by the treatments (P> 0.05) but NLE tended to deplete blood haemoglobin. It is recommended that for optimal
performance, inclusion of NLE in layers diets should be limited to 2.5 percent.