title: Feeding rumen-protected gamma-aminobutyric acid enhances the immune response and antioxidant status of heat-stressed lactating dairy cows.
abstract: This experiment was conducted to investigate the effects of rumen-protected gamma-aminobutyric acid (GABA) on immune function and antioxidant status in heat-stressed dairy cows. Sixty Holstein dairy cows were randomly assigned to 1 of 4 treatments according to a completely randomized block design. The treatments consisted of 0 (control), 40, 80, or 120mg of GABA/kg DM from rumen-protected GABA. The trial lasted 10 weeks. The average temperature-humidity indices at 0700, 1400 and 2200h were 78.4, 80.2 and 78.7, respectively. Rectal temperatures decreased linearly at 0700, 1400, and 2200h with increasing GABA. As the GABA increased, the immunoglobulin (Ig) A and IgG contents and the proportions of CD4(+) and CD8(+) T lymphocytes increased linearly (P<0.05), whereas concentrations of interleukin (IL)-2, IL-4, IL-6 and tumor necrosis factor-α (TNF-α) decreased linearly (P<0.05). The activities of superoxide dismutase (SOD), glutathione-peroxidase (GSH-PX) and total antioxidant capacity (T-AOC) increased linearly (P<0.05), whereas malondialdehyde (MDA) content decreased linearly (P<0.05) with increasing GABA. These results indicate that rumen-protected GABA supplementation to heat-stressed dairy cows can improve their immune function and antioxidant activity.
authors: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China; College of Animal Science and Technology, Anhui Agricultural University, Hefei, China.
authors: Jianbo
authors: J
authors: Cheng
authors: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China; Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing, China.
authors: Nan
authors: N
authors: Zheng
authors: College of Animal Science and Technology, Anhui Agricultural University, Hefei, China.
authors: Xianzhi
authors: X
authors: Sun
authors: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China; Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing, China.
authors: Songli
authors: S
authors: Li
authors: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
authors: Jiaqi
authors: J
authors: Wang
authors: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China; Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing, China. Electronic address: yangdongzhang1982@163.com.
authors: Yangdong
authors: Y
authors: Zhang
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D016516:CD4-CD8 Ratio; D002417:Cattle / Q000097:blood / Q000276:immunology / Q000502:physiology*; D002418:Cattle Diseases / Q000097:blood / Q000276:immunology / Q000378:metabolism / Q000517:prevention & control*; D016207:Cytokines / Q000097:blood / Q000276:immunology; D019587:Dietary Supplements / Q000032:analysis; D005260:Female; D018682:GABA Agents / Q000627:therapeutic use*; D018882:Heat Stress Disorders / Q000276:immunology / Q000378:metabolism / Q000517:prevention & control / Q000662:veterinary*; D018869:Heat-Shock Response / Q000187:drug effects*; D006358:Hot Temperature; D018384:Oxidative Stress / Q000187:drug effects; D012417:Rumen / Q000187:drug effects; D005680:gamma-Aminobutyric Acid / Q000627:therapeutic use*
chemical_list: D016207:Cytokines; D018682:GABA Agents; D005680:gamma-Aminobutyric Acid
keywords: Antioxidant activity; Gamma-aminobutyric acid; Heat stress; Immune function