The growth and haematological effects of ascorbic acid supplementation on coccidia-challenged broiler chickens

A total of one hundred and ninety two day old broiler chicks were used to evaluate the growth and heamatological effects of Ascorbic acid (AA) supplementation on coocidia-challenged broiler chickens. The design was a 4 x 2 factorial in a completely randomized design. The main-factor was the period or length of time of administering ascorbic acid (AA), while the sub-factor was the dosage of AA used for the feed composition. The birds were challenged with oocysts of Eimeria tenella at the end of the third week; and started manifesting signs of coccidiosis four days after challenge. The oocyst count and percentage mortality were significantly (P<0.05) different for the main-factors and the interactions, but not for the sub-factors. At the end of eight weeks experimental period, percentage mortality were significantly (P<0.05) different for the main-factors and the interactions, but not for the sub-factors; while the oocyst count were significantly (P<0.05) different for the main-factors, sub-factors and interactions. The haematological parameters – Packed Cell Volume (PCV), Haemoglobin (Hb), White Blood Cell (WBC), Red Blood Cell (RBC), Mean Corpuscular Volume (MCV) and Mean Corpuscular Haemoglobin Concentration (MCHC) were significantly (P<0.05) different for the main-factors, sub-factors and the interactions; except for the MCHC which was not significantly (P<0.05) different for the sub-factors and the interactions. The plasma constituents – plasma protein and plasma lipid were significantly (P<0.05) different for the main-factors and the sub-factors. Whereas plasma lipid was significantly (P<0.05) different for the interactions, it was not so for the plasma protein. It may be concluded that supplementing broiler diets with 150mgAA per Kg of feed has profound effect on growth and haematology which in turn leads to reduction in the severity of coccidiosis in birds.