Effects of Glutamine Administration before Transportation on the Growth Performance, Hormone Level and Antioxidant Function of Broilers after Transportation Stress

PurposeTo study the effects of glutamine (Gln) administration before transportation on growth performance, blood hormone levels and antioxidant capacity of stressed broilers.

Method300 healthy AA newborn broilers were selected and randomly divided into five groups. Group A and B were given 1 mL of normal saline, while group C, D and E were given 1 mL of normal saline with the concentration of 0.50, 0.75 and 1.00 g Gln per kg body weight of broilers respectively. Subsequently B, C, D and E were transported for five hours, and group A was the control group. After five hours of stress treatment, the chicks were weighed and blood samples were collected to assess the levels of corticosterone (CORT), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), lactate dehydrogenase (LDH), adrenocorticosteroid (ACTH) and reactive oxygen species (ROS). During the followed 14 days routine feeding, food intake and daily weight gain were determined.

Result(1) After five hours of transportation stress, weight loss was significantly observed in group B (P<0.05), but no weight loss was observed in broilers administrated Gln. At seven days of age, the average daily gain and average feed intake and feed efficiency of broilers in group B were significantly lower than those in control group (P<0.05), but compared with group B, Gln administration improved the average daily gain and average feed intake of broilers (P<0.05), the average feed intake and feed efficiency of the broilers in group D restored to the similar level of the control group. At fourteen days of age, the average daily gain, feed intake and feed efficiency of broilers in groups B were still significantly lower than those in control group (P<0.05), the improvement of Gln administration on the average feed intake and average daily gain was still observed (P<0.05), especially group D and E had restored to the level of control group, but the feed efficiency of group D and E was still lower than those in control group (P<0.05). (2) Compared with the control group, transport stress significantly increased the levels of CORT, ACTH, ROS, MDA and LDH in serum (P<0.05), while the activities of GSH-PX, SOD and CAT in serum were significantly decreased (P<0.05). Gavage of Gln before transport significantly improved the above hormone levels and enzyme activities (P<0.05), except for MDA concentration in group C (P>0.05), ROS concentration in group D was restored to the level of control group.

ConclusionFive hours transportation stress had negative impact on broiler growth performance, blood hormone level and antioxidant capacity. Administration of Gln before tramsportation could effectively alleviate the above effect of transportation stress, and 0.75 g/kg of Gln was the recommended dose to relieve the stress.