Abstract
A study was conducted to determine the effects of dietary interventions of vitamins A and C, methionine and lysine singly
and in combination on broilers challenged with Aspergillus flavus. The interventions were Vitamins A+C (A+C),
Methionine+Lysine (METH+LYS) and Vitamins A+C+METH+LYS. The experiment which was conducted for 8 weeks
employed a completely randomized design. Feed intake, weight gain, nutrient retention and feed conversion efficiency were significantly influenced (p<0.05) by dietary supplementation of the Aspergillus challenged birds. Highest feed intake (42.81g/bird/day) was observe for Aspergillus challenged birds supplemented with A+C+METH+LYS which compared favourably with the positive control birds (42.48g/bird/day). The lowest feed intake was observed for the negative control birds (Aspergillus challenged without dietary intervention). Weight gain was highest for the positive control bird (20.14g/bird/day). This value was similar to the value obtained for Aspergillus challenged birds supplemented with A+C+METH+LYS. Lowest weight gain was observed in the negative control birds (12.44g/bird/day). These birds also recorded significantly (p<0.05) lowest feed conversion efficiency (3.09). Haematological and serum indices showed no significant differences (p>0.05) however, higher lymphocytes values were observed in challenged birds with dietary intervention. As a general immune modulator, vitamins A and C with lysine and methionine may be an attractive alternative to the on-farm use of vaccines in poultry in the management of aspergillosis.
