Guwahati, May 25 : Scientists at the National Research Centre on Mithun (NRCM) at Jharnapani in Nagaland have broken new grounds by carrying out a successful embryo transfer, leading to the birth of the first ever mithun calf through this method. Mohan, as the newly-born calf has been christened, was delivered by a healthy female mithun on May 12 after she played the role of a surrogate mother.
“It is a landmark case, especially because the population of this animal is not in a comfortable status. The embryo transfer technology (ETT) that we resorted to will definitely help propagate quality germplasm of this magnificent species of animal,” says NRCM principal scientist K K Baruah. The NRCM in Nagaland is one of the several such research centres for different animals under the Indian Council of Agricultural Research (ICAR).
Similar efforts have been successfully carried out on cow, sheep, goat and horse, but this is the first time such an experiment has succeeded on mithun, claims Baruah. “Mithuns being exposed to the wild have been suffering from cross-breeding as well as in-breeding, posing a major threat to this animal so dear to the tribal communities in the Northeastern states. The ETT method has raised hopes of creating a quality stock of mithuns,” says Baruah.
Others who worked in the ETT team were NRCM director Chandan Rajkhowa, senior scientists M Mondal and Bhaskar Bora, while B C Sarmah, B C Deka and D J Dutta from the College of Veterinary Sciences, Guwahati, and Dr P Chakraborty from NRC on Yak in Dirang (Arunachal Pradesh).
Mithun (Bos frontalis) is the domesticated form of gaur (Bos gaurus) and is often referred to as the “ship of the highland” or “cattle of the mountains”. It is an example of the integration of agro-ecology, subsistence livelihood, culture and livestock rearing. People, however, mostly do not keep them at home, and let them remain in the jungles. They are reared under free range condition in dense forests in a very unique manner, with zero input, at altitudes ranging from 300 to 3,000 metres above sea level.
The last census conducted for mithuns in 2007 had put the number of this animal at around 2.64 lakh, of which Arunachal Pradesh alone had roughly 82 per cent of them. Nagaland (12.6%), Manipur (3.8%) and Mizoram (0.8%) are the other states where mithuns can be seen. While mithun is also consumed as meat, its milk is very rich in fat, proteins and other nutrients, compared to other milch animals. Moreover, its hides, when processed, give one of the best quality leathers.
The NRCM that has been engaged in propagation of mithuns in the region has been working on this project for the last five years. “Since mithuns are largely used as a meat animal, it is very important to promote better animals, which we have been trying to do through preservation and propagation of quality germ-plasm,” says Baruah.
Healthy female mithuns ovulate every 21 days, and give birth to one calf a year. “But since a sizeable population of female mithuns are not in a state of normal ovulation, we think converting them to surrogate mothers by ETT will lead to faster multiplication of mithuns,” he adds.
Comparing ETT to artificial insemination, Baruah says while the latter process only spreads superior male genetics across a herd of animals, embryo transfer technology would now help spread superior female genetics across a specific herd or even in many herds. “Moreover, each of these offspring like Mohan would potentially carry superior traits of the original mother, such as increased weight gain and more milk apart from disease control,” he adds.