Mitigating heat stress in broilers by dietary dried tamarind (Tamarindus indica L.) pulp: Effect on growth and blood traits, oxidative status and immune response

Abstract

The objective of the present study was to evaluate the effect different levels of dried pulp of tamarind (DTSP) on growth, lipid profile, oxidative status and immune response in broilers exposed to cyclic heat stress (HS). A total of 720 one-d-old male broiler chickens (Hubbard) were randomly allocated to 6 treatments (5 replicates) consisted of thermoneutral (TN) and HS. In this experiment, 4 groups of broilers under HS condition were fed four levels of dried tamarind seeds pulp (DTSP) powder at the rate of 0 (DTSP), 5 (DTSP-5), 7.5 (DTSP-7.5), 10 (DTSP-10) and 12.5 (DTSP-12.5) g/kg of feed for 35 d of age. Body weight and feed conversion ratio (FCR) increased (p < 0.05) in the TN and DTSP fed broilers. Blood concentration of paraoxonase-1 (PON1) was higher (p < 0.05) in TN and DTSP-10 and DTSP-12.5. However, antibody titer against Newcastle disease (ND) was higher (p < 0.05) in TN, DTSP-7.5, DTSP-10 and DTSP-12.5. Blood cholesterol and triglyceride were lower (p < 0.05) in TN, DTSP-7.5, DTSP-10 and DTSP-12.5. However, blood HDL was higher (p < 0.05) in DTSP-10 and DTSP-12.5. Blood LDL was significantly lower in DTSP-7.5, DTSP-10 and DTSP-12.5. Significantly higher total leucocytes count (TLC) was found in TN and DTSP-12.5; however, heterophils were significantly lower in the same group. In contrast, lymphocytes increased (p < 0.05) in TN, DTSP-7.5, DTSP-10 and DTSP-12.5, while monocytes was significantly decreased in the same group. In conclusion, DTSP improved growth, cholesterol profile, PON1 and leucocytes count and immune response against ND in broilers exposed to heat stress.