The Effect of Dietary Supplementation with Zinc Amino Acids on Immunity, Antioxidant Capacity, and Gut Microbiota Composition in Calves

Pengxia Hou; Bo Li; Yan Wang; Dan Li; Xiaoyu Huang; Wenyang Sun; Xiaojun Liang; Enping Zhang

doi:10.3390/ani13091570

The Effect of Dietary Supplementation with Zinc Amino Acids on Immunity, Antioxidant Capacity, and Gut Microbiota Composition in Calves

Animals (Basel). 2023 May 8;13(9):1570. doi: 10.3390/ani13091570.

Authors

Pengxia Hou¹, Bo Li¹, Yan Wang¹, Dan Li¹, Xiaoyu Huang¹, Wenyang Sun², Xiaojun Liang², Enping Zhang¹

Affiliations

¹ College of Animal Science and Technology, Northwest A&F University, Xianyang 712100, China.
² Ningxia Academy of Agriculture and Forestry Science, Institute of Animal, Yinchuan 750002, China.

Abstract

The aim of this study was to investigate the effect of dietary supplementation with zinc (Zn) amino acids at different concentrations on immunity, antioxidant capacity, and gut microbiota composition in calves. Twenty-four one-month-old healthy Angus calves of comparable body weight were randomly divided into three groups (four males and four females in each group) based on the amount of Zn supplementation added to the feed the animals received: group A, 40 mg/kg DM; group B, 80 mg/kg DM; and group C, 120 mg/kg DM. The experiment ended when calves reached three months of age (weaning period). The increase in dietary Zn amino acid content promoted the growth of calves, and the average daily weight gain increased by 36.58% (p < 0.05) in group C compared with group A. With the increase in the content of dietary Zn amino acids, the indexes of serum immune functions initially increased and then decreased; in particular, the content of immunoglobulin M in group A and group B was higher than that in group C (p < 0.05), whereas the content of interleukin-2 in group B was higher than that in the other two groups (p < 0.05). In addition, the content of superoxide dismutase and total antioxidant capacity in the serum of calves in group B was higher than that in group C (p < 0.05), and the MDA level was lower than in group C (p < 0.05). Moreover, alpha diversity in the gut microbiota of calves in group B was higher than that in group A and group C (p < 0.05); the dominant phyla were Firmicutes and Bacteroidota, whereas the dominant genera were Unclassified-Lachnospiraceae and Ruminococcus. Linear discriminant analysis showed that the relative abundance of Bacteroides in the gut microbiota of calves in group B was higher than that in group A, and the relative abundance of Prevotellaceae-UCG-003 was higher compared to that in experimental group C. Thus, dietary supplementation of 80 mg/kg of Zn amino acids to calves could improve the immune function and antioxidant capacity, as well as enrich and regulate the equilibrium of gut microbiota, thus promoting the healthy growth of calves.

Keywords: Bacteroides; Prevotellaceae-UCG-003; calves; gut microbiota; zinc amino acids.

Grants and funding

Research supported by the National Key R&D Program of China (No. 2021YFD1100508) and the Ningxia Hui Autonomous Region agricultural science and technology independent innovation project (No. NKYQ-20-03, and NGSB-2021-12).