Osmoprotective function of betaine maintains the physiological parameters of quail raised in tropical environments

Abstract

The high environmental temperature in the tropics adversely affects the physiology and performance of poultry. Betaine is an organic osmolyte that assists the birds in counteracting the deleterious effects of heat stress. This study observed the physiological parameters of laying quail raised in tropical environments and receiving betaine supplementation in the diet. A total of 224 21-day-old quails were distributed to two treatments with seven replicates of 16 birds. The treatments were the basal diet (Control) and the basal diet supplemented with 1.5 g/kg betaine (Betaine). The rectal temperature, respiration rate, and tonic immobility were measured in the morning (07.00h), afternoon (13.00h), and evening (19.00h). The temperature humidity index in the morning, afternoon, and evening were 24.7, 29.4, and 27.6, respectively, suggesting the birds expressing heat stress. Administering betaine in the diet reduces the rectal temperature, respiration rate, and tonic immobility in all measurement times (P<0.01), indicating that betaine maintains the physiological condition in quail. In conclusion, betaine functions as an organic osmolyte to assist the birds in coping with heat stress