KOLLAM With its dark eyes and brown coat Abhimanyu may look like any other calf, but what makes it unique is the way it was born. The calf is the result of a major research breakthrough, produced from a frozen IVF (in vitro fertilisation) embryo as part of the efforts to conserve the indigenous Vechur breed by the Kerala Livestock Development Board (KLDB).
A team of researchers could successfully establish the pregnancy in a surrogate and the calf was born in September at the Mattupetty farm, implemented under the Rashtriya Gokul Mission, . Though they could produce calves using fresh IVF embryos earlier, it is for the first time a calf was produced with frozen IVF embryo.
Cryopreserved
“The embryo used to produce the calf was frozen (cryopreserved) in liquid nitrogen at 200 degrees below zero for nearly two months before it was revived and transferred into a surrogate. It’s for the first time in the country a Vechur cow was produced through the process,” J. Anoop, Deputy General Manager, KLDB, told The Hindu.
The technique is employed for the production of genetically superior indigenous breeds and researchers at the farm have been trying to produce Vechur and Sahiwal calves since 2020.
“We have a lab for embryo transfer where Multiple Ovulation Embryo Transfer (MOET) was earlier carried out for bull calf production. IVF is a more advanced technology in which we collect oocytes from the donor cow and mature it for 22 to 24 hours. High pedigree semen is used to fertilise it and the zygote is later moved to culture medium for incubation. It takes around seven days for the embryo to develop and it is then transferred to the uterus of a suitable recipient animal,” says Dr. Anoop, who led the team of researchers that also includes doctors Avinash, Ramesh and Praveen.
While normal crossbreeds produce calves every year, the calving interval of indigenous breeds like Vechur is wider.
“In IVF method usually four to 16 oocytes are aspirated from a cow at a time and we can collect a minimum of 12 oocytes a month. From that only half will develop into embryos, using which we can establish two pregnancies every month. This way we can produce more than 20 Vechur calves every year using surrogates that can be of any breed. It’s a major milestone when we consider the conservation angle.”
Dr. Anoop adds that the embryos can be cryopreserved for several years before they are revived and used. “The biggest advantage is that we need not produce calves to conserve a particular breed. Instead we can freeze embryos and revive them if there is a contingency and these frozen embryos can be transported to any part of the globe,” he adds.
Published - October 22, 2022 07:27 pm IST
