Dietary betaine improves meat quality and oxidative status of broilers under heat stress

In order to investigate the effects of dietary betaine on meat quality and oxidative status of broilers under heat stress (HS), a total of 144 Arbor Acres male broilers were randomly allocated to three groups with six replicates of eight broilers per replicate from 21 to 42 days of age. The broilers in the control group were raised at 22 °C and received a basal diet, and the broilers in the other two groups were raised at 34 °C from 9:00 to 17:00 and at 22 °C for the rest of the time and fed a basal diet with or without 1000 mg kg-1 betaine.Dietary betaine supplementation tended (P < 0.1) to reverse the decreased body weight gain and feed intake of broilers induced by HS. The decreased redness (a* value) of breast muscle in broilers under HS was restored (P < 0.05) by betaine, which tended (P < 0.1) to decrease drip loss of breast muscle. The broilers fed betaine-supplemented diets had a tendency (P < 0.1) to increase moisture content but decrease crude protein content of breast muscle in broilers under HS. Moreover, betaine resulted in higher (P < 0.05) glutathione content and activities of superoxide dismutase and glutathione peroxidase but lower (P < 0.05) malondialdehyde content in breast muscle of broilers exposed to HS.Dietary betaine supplementation alleviated the negative effects of HS on some traits of meat quality and oxidative status of broilers. © 2018 Society of Chemical Industry.