Effects of savory aqueous extract on performance, carcass traits, some blood biochemical and immune parameters of broiler chickens under heat stress condition

Abstract

An experiment was done to study effects of savory aqueous extract on performance, carcass traits, some blood biochemical and immune parameters of broiler chickens under heat stress condition. To do this 320 day-old Ross chickens were assigned to four distinct treatments in a complete randomized design. Each treatment was given to four replicates of twenty birds. Variables were heat stress (34±2°C for 8 hours) and savory extract (0.4 ml/L) in drinking water. At different weeks of trial, feed intake (FI), weight gain (WG) and feed conversion ratio (FCR) was measured. Some relative weight of different organs (dressing, breast, thigh, liver, heart, spleen and bursa of Fabricus) determined at d 42 of age. The blood serum glucose and plasma content of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) were measured after blood sampling at d 42 of age. Plasma IgG were quantified on days 21, 28, 35 and 42. The savory extract did not affect FCR, or the relative weights of different organs (p>0.05). BW and FI increased with savory oil inclusion (p0.05). Totally, blood IgG of heat stressed broilers, increased with savory extract treating (p<0.05). In conclusion, under heat stress situations, 0.4 ml/L of savory extract improves economic proficiency in broiler flocks due to accumulation of minute advantages in greater WG, FI, and improved IG and lowered hepatic enzymes.

Keywords

• heat stress
• hepatic enzymes
• immune function
• performance
• savory
• aqueous extract
• broiler chickens