BIOTECHNOLOGY - V. H. Gerasymenko - 2006

Part II. Applied Biotechnologies

Chapter 12. BIOTECHNOLOGY OF HORMONE PRODUCTION

12.3. PRODUCTION OF SOMATOTROPIN

12.3.1. Application of recombinant somatotropin in animal husbandry

Following the Isolation of the human somatotropin Gene, cDNA copies of this gene from numerous agricultural species (cattle, sheep, pigs, poultry) were obtained, cloned, and expressed in E. coli and other microorganisms. Overproduction strains have been successfully engineered for several somatotropic Hormones (Nikolaychuk V.I., Horbatenko I.V., 1999).

Today, somatotropin is widely used in livestock production to enhance milk and meat yields in farm animals. Research has demonstrated that bacterial-derived bovine somatotropin stimulates Lactation in dairy cows just as effectively as the natural hormone extracted from the Pituitary Gland. According to various studies, both short-term (14 days) and long-term (188 days) administration of somatotropin resulted in a sustained increase in milk yield (under daily injection protocols). With daily doses ranging from 13.5 to 40.5 mg per animal, milk output increased by 10% to 50%, depending on the dosage and housing conditions. Experts estimate that large-scale Structure/175.html">Implementation of this biotechnology in dairy farming could boost milk production by an average of 23% to 31%.

Studies have shown that the milk quality from cows receiving prolonged somatotropin Treatment is virtually identical to control samples and contains no detectable residues of the administered Growth Hormone. Furthermore, administration of somatotropin for up to six years does not adversely affect other physiological, somatic, or behavioral CHARACTERISTICS OF THE experimental animals.

Positive outcomes have also been achieved using bacterial somatotropin formulations in beef production. Daily injections of these hormonal preparations in young cattle significantly stimulated growth and Muscle tissue development. Daily weight gains varied within 20–30%, depending on the animal species, housing conditions, and hormone dosage, which helped shorten the fattening period for young stock. In addition, a noticeable reduction in feed conversion ratios per unit of gain was observed. In young pigs and ruminants, the accelerated GROWTH AND DEVELOPMENT induced by recombinant somatotropin were accompanied by an increased protein content and reduced fat deposition in Tissues, thereby substantially improving the quality and commercial value of the meat products. However, the metabolic alterations triggered by exogenous somatotropin vary across animal species. For instance, some researchers report a positive effect of somatotropin injections on weight gain dynamics in meat sheep, though without a corresponding reduction in fat deposits. Intensive administration of somatotropin to animals does not lead to the accumulation of the drug in food products, which is a key advantage distinguishing somatotropin from Steroid Hormones and Antibiotics previously used for similar purposes.

The requirement for daily injections hinders the widespread adoption of somatotropin in animal husbandry, as it complicates production and drives up costs. However, recent research has focused successfully on developing sustained-release formulations of these hormonal drugs, which form a depot within the body and eliminate The Need for daily injections.