Effect of scent leaf-extract (ocimum grafissimum) and neem leaf-extract (Azadirachta Indica) fed as antimicrobial feed additive on finishing broilers

Abstract

100 Marshal White broiler chicks at 5-weeks old were fed on Scent leaf-extract (SLE) (Ocimum gratissimum) and Neem leaf-extract (NLE) (Azadirachta indica)to determine the effect of these leaf-extracts as antimicrobial feed additive. The Fresh leaf-extracts were administered on daily basis to the birds for four weeks at varying concentrations of 0ml, 10ml 20ml, 30ml and 40ml per liter of water. Water intake, feed intake, growth performance and mortality rate of the birds were monitored during the period. Microbial levels of blood and fecal samples of the treatments were analyzed at the end of experiment. The results indicated a progressive decrease of water intake among chicks on NLE as the concentrations increased. The chicks on SLE did not show any significant water intake reduction (p>0.01) until 30ml concentration. Feed intake was significantly affected (P<0.05) by the leaf extracts’ concentrations. The chicks on NLE had their feed intake progressively depressed as the concentration of the extract increased, while chicks on SLE had their feed intake depressed at 30ml/L concentration. The weight gain of the chicks on both extracts were higher than the weight gain without any extract up till 30ml/L for SLE and 10ml/L for NLE. The mortality rate of the chicks on SLE were less than chicks without the scent leaf extract up till the level of 30ml/L, while the mortality rate of those on NLE were not. There was continuous reduction of white and red blood cell per phial in the stool microscopy wet preparation in both NLE and SLE as the concentration of the extracts increased. The percentage of microbial isolates from blood and stool culture decreased progressively as the leaf-extract increased.

Key words: Scent leaf extract, Neem leaf extract, broiler chicks, microbial feed additive.