INCLUSION RATE AND PHYSIOLOGICAL EFFECTS OF PROLONGED FEEDING OF COCOA BEAN CAKE ON LAYERS

Résumé

The effect of inclusion of cocoa bean cake (CBC) on productive performance and physiological response of Isa Brown pullets to prolonged feeding of CBC were investigated. Dietary inclusion of CBC (0, 50, 100 and 200g kg^-1 diet) were monitored in typical poultry diet from day old to 51 weeks of age. Sexual maturity and attained of 50% hen-day production were delayed with increasing level of CBC. Egg quality indices were higher (P < 0.05) at 200g kg^-1 CBC diet but with reduced (P < 0.05) shell thickness. CBC had no significant influence on yolk or whole egg cholesterol, follicular weight and number. Layers on 0 and 50 kg^-1 CBC diets had higher           (P < 0.05) percentage of yellow follicles but lower white follicles. Liver and pancreatic hypertrophy were observed for CBC-fed layers but with reduced (P < 0.05) abdominal fat and oviduct length. The long term feeding of CBC at level more than 50g kg^-1 diet progressively had a deteriorating effect on laying performance and follicular development.