A Garole sheep in the Sunderbans. Photo credit: S. Pan, WBUAFS, Calcutta

New Delhi, Sept. 27: Scientists have transferred a biological trait from a sheep native to the Sunderbans into sheep from elsewhere in India in an attempt to reap rewards that settlers in Australia had drawn, unintentionally, two centuries ago.

Two research teams have independently developed crossbreeds of the Garole sheep from the Sunderbans with sheep from Rajasthan and the Deccan region to produce more lambs per ewe, harnessing a special gene possessed by Garole.

The Garole graze in marshy lands and carry a gene called the Booroola fecundity gene (Fec-B) through which nearly 80 per cent pregnancies yield twin or triplet lambs. Ewes of all other breeds of sheep in India usually produce only one lamb per pregnancy. But the Garole are small sheep, weighing an average of 15kg, while attractive breeds for mutton production weigh twice as much.

Now, scientists at the Central Sheep and Wool Research Institute, Avikanagar in Rajasthan, have crossed the Garole with Malpura, a popular breed of sheep in northwestern India, to produce crossbreeds that show the high levels of prolific breeding as the Garole. The crossbred ewes yield more lambs and their weight is similar to the parent Malpura that can grow up to 30kg.

“The crossbreeds have the best qualities from both the breeds,” said Amrit Lal Arora, head of the animal genetics and breeding at the CSWRI. “The ewes give two or three lambs each time with no compromise on the body weight,” he told The Telegraph.

The CSWRI has just initiated a study to analyse the potential economic benefits to livestock rearers if the crossbred animals were to be released in northwestern India. “We expect the multiple births to give them more profits,” Arora said.

Another institution, which had launched an effort to cross Garole with Deccani sheep nearly a decade ago, has already distributed crossbred animals to livestock rearers in Maharashtra, Andhra Pradesh and Karnataka.

“We expect livestock owners to get 30 per cent higher yield of lambs,” said Chanda Nimbkar, the director of animal husbandry at the Nimbkar Agricultural Research Institute (NARI), Phaltan in Maharashtra, a non-government institution set up by her father.

Under a new project supported by India’s department of biotechnology, NARI will continue to distribute crossbred rams that carry the Fec-B gene into more flocks in these states for further breeding.

The projects have been under way at a time when the domestic demand for meat has been increasing steadily and, researchers estimate, the price of mutton has climbed about 10 per cent to 20 per cent each year over the past several years.

But some scientists caution that maintaining the gene in livestock won’t be easy.

“This is a promising development at the laboratory level,” said Subhransu Pan, professor at the West Bengal University of Animal and Fisheries Sciences, Calcutta. “But to maintain this gene down generations, livestock rearers may have to keep pedigree records and select only animals with the gene for breeding — this could be difficult in our conditions,” Pan told The Telegraph.

However, animal breeders point out that the Garole’s earliest contribution to increasing the population of other breeds of sheep may have occurred in Australia more than 200 years ago — unintentionally, and without pedigree tracking.

Scientists say archived historical records from the late 18th century show that a number of Garole sheep from Bengal had been shipped to Australia in 1792 and in 1793. “They were not taken there for boosting fecundity, but when they reached there, they probably mingled with other sheep and helped increase the number of lambs in those breeds,” Nimbkar said.

It was only in 2002 that scientists in New Zealand analysed genes of sheep from eight countries and produced genetic evidence to support historical records that Garole sheep had been introduced in Australia from Bengal in the late 18th century.