Role of somatotropin in livestock growth and lactation: A review

Somatotropin (ST) treatment of domestic animals markedly enhances the efficiency of nutrients through the orchestration of many physiological processes in different tissues thereby enabling these nutrients to be used for increase milk synthesis and body growth. This progress was further ignited with the introduction of biotechnology leading to the production of large quantities of recombinant bovine ST (bST) and porcine ST (pST). The availability of recombinant bST and pST resulted in an exponential increase in investigations that explored their role in growth and lactation biology. These coordinated effects of ST involve tissue specific changes to homeostatic signals. In addition to efficacy, this review summarizes the normal effects of ST on growth, lactation, carbohydrate and protein metabolism and mechanisms that mediate these effects in domestic animals.