EFFECT OF ENZYME SUPPLEMENTATION ON PERFORMANCE OF PULLET CHICKS FED DIFFERENT LEVEL OF DIETARY FIBRE

EFFECT OF ENZYME SUPPLEMENTATION ON PERFORMANCE OF PULLET CHICKS FED DIFFERENT LEVEL OF DIETARY FIBRE

ABSTRACT

A study was conducted to evaluate the performance of pullet chicks fed diets containing varying levels of fibre and supplementary enzyme. One hundred and twenty 3 -week old Harco black pullet chicks averaging 249.87 – 250.23g body weight were randomly divided into 8 groups of 15 birds each. The groups were randomly assigned to 8 energetic  (11.78-11.96 MJ/Kg ME)  and nitrogenous (20% crude protein) diets in a 4 x 2 factorial arrangement involving four levels (5.0, 6.0, 7.0 and 8.0%) of fibre and two enzyme levels (0 and 0.25%). Each treatment was replicated 3 times with 5 birds per replicate. Feed and water were supplied ad libitum to the birds during the 8 weeks experimental period. Results showed that the weight gain of chicks that consumed diets without enzyme supplementation decreased significantly (P<0.01) as the dietary fibre level increased beyond 6% level . Average daily feed intake (ADFI) also increased significantly (P<0.01) at the 7 and 8% dietary fibre levels. Chicks fed 6% crude fibre diet with enzyme supplementation had significantly (P<0.01) higher average daily weight gain (ADWG), final body weight (FBW) and protein efficiency ratio (PER) and lower (P<0.01) cost of feed per kg weight gain than those fed the control diet. There was a significant (P<0.01) increase in the intake of crude fibre (CF) and nitrogen-free extract (NFE) as the fibre level in the diet increased beyond 6%. Dry matter (DM), nitrogen and CF retentions were significantly (P<0.01) decreased as the dietary fibre increased beyond 6% inclusion level. Increasing levels of crude fibre in the diets had no significant (P>0.01) effect on the WBC and MCHC but affected the rPCV, Hb, RBC, MCH and MCV significantly (P<0.01). There were significant (P<0.01) interactions between dietary fibre and enzyme levels on ADWG, FBW, ADFI, FCR, PER , cost of total feed intake and feed cost per kg weight gain. Enzyme supplementation increased (P<0.01) ADWG, FBW and PER at the 6, 7 and 8% fibre inclusion levels; reduced (P<0.01) feed intake at the 5, 7 and 8% fibre inclusion levels ; reduced (P<0.01) FCR values at all the fibre inclusion levels and reduced (P<0.01) the cost of total feed intake and feed cost per kg weight gain at all the fibre inclusion levels. There were also significant (P<0.01) interactions between fibre and enzyme levels on NFE intake, DM , nitrogen, CF, EE, NFE, PCV, Hb, RBC, MCH and MCV. Enzyme supplementation reduced (P<0.01) NFE intake at the 7% fibre inclusion level; increased(P<0.01)  the retention of DM at the 5% and 7 %, fibre inclusion levels;  increased (P<0.01) nitrogen retention at the 5%, 6% and8% fibre inclusion levels;  increased (P<0.01) CF retention at the 6%,7% and 8% fibre inclusion levels and   increased(P<0.01)  EE and NFE retentions at the 7% and 8% fibre inclusion levels; increased (P<0.01) PCV, Hb and RBC at the 6% and 7 %, fibre inclusion levels and   increased (P<0.01) MCH and MCV at the 7% fibre inclusion level. Based on the results obtained in the present study, it was concluded that pullet chicks can be fed 6% crude fibre diet without supplementary enzyme and that up to 8% dietary fibre can be included in enzyme- supplemented pullet chicks’ diet without adverse effects on growth performance of chicks.