How Does Somatotropin Affect Milk Production?

To affect a cows milk production, bST must be injected into the animal on a regular basis, similar to the way insulin must be regularly injected into people who have certain types of diabetes. Feeding bST to cows will not work. Amino acids and peptides are the building blocks of proteins. 

The hormone bST is a complex protein that is immediately broken down into small, inactive amino acids and peptides and rendered ineffective when it enters a cows digestive system. How often a cow must be injected with bST will depend on whether a bST product can be developed that releases the hormone gradually over a long period of time. 


Milk yields are significantly increased when cows are injected with bST, although not as much as some reports in popular newspapers and magazines suggest. The exact details of how bST increases milk production are not known, but it is thought that blood flow to the cows mammary (milk-producing) gland is increased.

What is Bovine Somatotropin?

Bovine Somatotropin (bST) is being in use in Pakistan in commercial dairies. Here it is commonly used by the brand name of  "BOOSTIN" which is the research product of Monsanto and in USA Monsanto has a marketing rights and market it with the name of "POSILAC"whereas in other part of world Eli Lilly (Elanco animal Health) has marketing rights and available with the brand name "SOMATECH". Currently in Pakistan Elanco's product "SOMATECH" is being marketed by ICI Pakistan Limited Animal Health division.  


Bovine somatotropin is a growth hormone found in cattle. The word bovine refers to cattle, and the word somatotropin refers to the name of the hormone. Hormones are chemicals that are secreted by glands within the body. They are natural substances that affect the way the body operates. Bovine somatotropin, abbreviated as bST, is a protein hormone produced in cattle by the pituitary gland located at the base of the animals brain.