From AgInnovation Ontario
By Jane Robinson
Pavneesh Madan was just about eight years old when he first peered at an embryo under a microscope. That first glimpse began his lifelong focus on fertilized eggs, and particularly the field of early embryonic mortality in dairy cattle.
Madan is an associate professor, veterinarian and researcher at the University of Guelph’s Ontario Veterinary College in the Department of Biomedical Sciences, and for the past several years he’s been working on ways to identify healthy and unhealthy dairy embryos before they are used in embryo transfer. “Early embryonic mortality costs dairy farmers a lot of money,” says Madan.
He cites a United Nations survey that put global losses at $1.8 trillion annually for embryonic mortality in beef and dairy cattle around the world.
“Maybe we can prevent some of these losses by understanding how the embryo develops, how to recognize a healthy or unhealthy embryo in the first few days of development, and then being able to choose only the good ones,” he says.
In the course of developing a non-invasive method to assess embryo health in dairy cows, Madan discovered an exciting spin-off from his research that could help alleviate some of the immeasurable losses from human miscarriages.
“If you talk to any clinician in the human field of in vitro fertilization (IVF), their biggest concern is that they don’t have a good test to assess which harvested embryos should be implanted, for the best possible outcome,” Madan says.
There is poor correlation between a visual inspection of an embryo under the microscope, and the potential viability of it for a human pregnancy. Madan knows there is a need for a better test. And that’s exactly what he’s working on.
In dairy cattle, Madan’s test for embryonic health involves placing young embryos in a media to live and grow for a few hours to a few days.
“My hypothesis is that if an embryo is healthy, it will eat food and excrete differently than an unhealthy embryo. By assessing what is in the “spent” media (after embryos have been living in it) we have been able to pick up markers for embryonic health and markers that indicate the embryo’s demise,” he says.
When he collaborated with IVF clinics across Ontario, evaluating similar spent media used with human embryos, Madan found an intriguing similarity between markers indicating early embryo health in humans and dairy cows.
“Cows and humans share many similarities for embryo development including ovulation rate, rate of embryo development and metabolism, and a nine-month gestation,” Madan says.
Dairy embryos provide the perfect opportunity for Madan to finetune a test to evaluate embryo health, and then translate his work for use in the human population.
“My work is to ultimately develop this process of embryo assessment into a simple test that can be done in smaller labs for dairy cows and for people,” he says.