INFLUENCE OF DIETARY BETAINE ON HAEMATOLOGY AND SERUM BIOCHEMISTRY OF HEAT-STRESSED BROILER CHICKENS

Résumé

Heat stress has been negatively implicated in the physiological changes of farm animals, including respiratory alkalosis, endocrine problems, electrolyte imbalance among others. Betaine has been used to mitigate the impact of high ambient temperatures on the performance and health status of broilers. This study investigated the haematological and serum biochemical response of broilers fed different levels at dietary betaine for 56 days during dry season using 180 day-old broiler chicks randomly assigned to five dietary treatments with 36 birds per treatment, each treatment was replicated thrice with 12 birds per replicate in a completely randomized design. Treatment 1 was the control diet without betaine while diets 2, 3, 4 and 5 contained 1, 2, 3, and 4g of betaine/kg of feed respectively. Results revealed that haematological parameters of the birds were not significantly affected by dietary betaine, except platelet which was significantly affected (p<0.05) with increasing level of betaine. Chickens on diet 5 had significantly superior (p < 0.05) platelet counts (165.50 x 10³/μl) when compared with those on other diets. Platelet counts in chickens on T₄ (147.00 x 10³/μL), T₃(135.50x10³/μL) and T₂(130.50 x 10³/μL) were similar. Serum albumin concentrations were significantly higher (p<0.05) in broilers in other treatments compared with those on control diet. Chickens on treatment 3 had superior (p < 0.05) albumin value of 1.55 compared with those on other diets. Albumin in treatments 2, 4, and 5 were statistically similar. Serum electrolytes were significantly reduced (p<0.05) as dietary betaine increased. Other serum parameters were not significantly
(p>0.05) affected.