Adiponectin and Its Physiological Function in Ruminant Livestock

Abstract

Adiponectin is a hormone that belongs to a group known as adipokines that white adipose tissue is a primary source of it. This hormone has multiple functions in livestock, including lipid metabolism, energy regulation, immunity, and insulin sensitivity, with energy metabolism and ovarian function being the most important. Adiponectin’s action is determined by its interactions with its receptors, including AdipoR1 and AdipoR2. These receptors (AdipoR1 and AdipoR2) are found in multiple tissues, including adipose tissue, skeletal muscles, and other tissues. Besides, these receptors are expressed in the hypothalamus, pituitary, and gonadotropin-releasing glands. Accordingly, adiponectin and its receptors are believed to affect livestock productivity and reproduction. Adiponectin promotes skeletal muscle proliferation by interacting with the p38 mitogen-activated protein kinase (p38-MAPK) pathway, thereby influencing carcass characteristics (including meat marbling, ribeye muscle area, and carcass fat thickness). Besides, it appears to be related to mammal fertility because adiponectin is located on the hypothalamic-pituitary-gonadal (HPG) axis, which is involved in mammal reproductive functions. However, the physiological action of adiponectin in livestock needs to be clarified. It is crucial to investigate the association of adiponectin with productive and reproductive traits in livestock. This review summarizes the adiponectin effects on productivity along with reproductive traits in livestock.