Ojo O. A., Lawal K. F.
Abstract: Rearing of birds is a major means of meeting the growing demand of animal protein in Nigeria and the world as a whole. Heat stress poses a major threat to the success of poultry farming as it causes reduced feed intake and weight gain among others. Commercial antioxidants are expensive and not readily available especially to small holder farmers, therefore there is an urgent need to source for a cheap, unconventional source of antioxidant to mitigate the adverse effect of heat stress. A total number of 45 cockerels were randomly distributed into 5 treatment groups, replicated 3 times with 3 cockerels per replicate under elevated summer temperature to investigate the effect of Vernonia amygdalina leaves extract (VALE) supplementation via drinking water on their reproductive characteristics which lasted for eight weeks. Parameters evaluated under semen qualitative analysis were semen color, volume, concentration, motility, pH, live dead ratio, mass activity, morphology while under seminal biochemistry, lipid peroxidation (MDA) and total antioxidant capacity (GPx and SOD) were evaluated. The results of proximate analysis revealed the presence of high crude protein (23.68 %), moisture (6.68 %), ash (8.90 %), crude lipids (0.37 %), crude fibre (7.32 %), CHO (53.03 %) and calorific value (1295.19KJ/mole).The result of phyto chemical screening revealed saponin (+++), tannin (+++), phenol (+++), flavonoid (++), alkaloid (++), steroid (++), glycoside (++) and anthraquinone (++). Results obtained from semen quality showed that the volume (0.62ml) and concentration (615 x 109) were higher in birds given 90mls of VALE, also the values of SOD was higher at 90mls (1069.19u/l) while that of GPx was lowest at T3 (12.50u/l) and T5 (16.94u/l). In conclusion, VALE at 90mls can be used as a natural source of antioxidant. Further studies can be conducted using higher concentrations of VALE.
Keywords: Vernonia amygdalina, heat stress, cockerel, leave extract, semen, motility, concentration