Affordability is a sensitive issue and all discussions often ends up with a demand for subsidizing the milk supply, adding to the growing subsidy burden to the country. While providing milk to poor at a lower rate, by itself is a good idea, there is no practical way to ensure only deserving people get it without the scheme becoming a rip off for unscrupulous elements to hijack the scheme for siphoning off public funds. The recent Karnataka scheme to give Rs 2 per liter of milk as a subsidy to producers, which in turn will inevitably increase the price of milk to consumers, is a case worth watching. Though this scheme may lead to increased production, there is bound to be a shrinking of consumption mostly caused by very low income population shying away from the milk market with some catastrophic consequences.
Synthetic Bovine Somato Tropine (BST) is a hormone recommended for administration to cows to increase the milk yield significantly and it is reported to be widely being used in many countries, probably the consumer never knowing about it. In some countries there are regulations requiring the packers to declare on the label the use of such hormones but there are others getting away with it due to lax food safety vigilant system. It has been claimed that use of hormones such as BST is safe, though this contention is not beyond challenge. The validity of claims of safety of this product is supported by clearances by WHO, American Medical Association and FDA of USA. Of course one of the justifications in allowing such milk boosting technologies is that less number of cows needs to be maintained and this can reduce significantly emission of green house gases by these animals!
BST occurs naturally in bovine pituitary gland of cattle and is thought to be associated with milk production. Using this logic a synthetic version of this hormone was evolved by recombinant DNA technique using a genetically modified bacteria and the commercial product, usually referred to as rbST or rBGH, is being used as an injection once in two weeks in milk yielding cows to get on an average 17% more yield of milk. The new GM based hormone was being produced by Monsanto Chemicals of USA under the brand name Posilac and was first approved in 1993 by FDA of USA. Now it is being used in 20 countries, the hormone directly injected into the udder. Recent sale of the Posilac business portfolio by Monsanto has generated fresh discussion regarding the long term viability of the product in the light of very significant consumer resistance in some countries and prominent label declarations by the competitors that their milk is 'untreated with hormone'
rBGH when injected causes painful udder diseases like mastitis and clinical lameness. There were reports that pus and bacteria formed after the injection contaminate the milk and the conventional pasteurization might not be adequate to ensure safety. To complicate the problem high doses of antibiotics often used by the producers to suppress infection find their way into the milk from such animals posing risks to the consumers. The Insulin Growth Hormone (IGF-1) formed in the mammary glands at higher levels as a result of rBGH injection and actually responsible for the milk yield increase, is also is a matter of concern. IGF-1 is secreted at levels five times higher than that in normal cows when rBGH is used and it is not digested in human GI tract. IGF-1 is implicated in cancers affecting breast, pancreas and colon. rBGH by itself is destroyed during thermal processing in the dairy and in the digestive tract of humans and as such might not be a hazard. Probably some more studies are necessary for creating adequate consumer confidence regarding adverse consequences of consumption of milk from hormone treated cows.
Another approach for increased milk production involves suppression of serotonin in the mammalian glands using drugs. Preliminary studies indicate 15% increase in yield can be achieved. However there is a long way to go for this concept to get established with out any adverse consequences. As serotonin level in brain is associated with depression, whether the cows will become 'depressed' by this treatment may pose problems from animal activists regarding such 'inhuman' treatment.
India has a vital stake in this development as milk productivity is still well below the yields achieved in dairy countries like New Zealand and safe ways for boosting yield can have far reaching beneficial impact on the livelihood of dairy farmers in the country.