A Michigan State University researcher has received a $1.65 million grant that looks to bring a better understanding about fertility treatments in women by studying the effect of hormones on ovulation and reproduction in cows.

“Cattle are a useful model because they have a relatively long reproductive cycle similar to women and they ovulate a single egg at the end of each cycle,” said James Ireland, a professor of reproductive physiology. “Plus, a cow with a smaller egg reserve typically doesn’t respond to fertility methods as well as cattle who have more eggs stored, a phenomenon women often experience too.”

With funding from the National Institutes of Health and the U.S. Department of Agriculture, Ireland will lead the five-year study with Keith Latham, co-director of the Reproductive & Developmental Sciences Program at Michigan State. Richard Leach, chair of the university’s department of obstetrics, gynecology and reproductive biology, will also contribute to the project.

Although many fertility techniques used today have been developed using cows as a model, Ireland and his research team are the first to try and establish how increased doses of a certain fertility hormone given to women during in vitro fertilization (IVF) can positively or negatively affect live birth rates.

Follicle stimulating hormone (FSH) is produced by the pituitary gland and controls the ovaries in women and testes in men. It’s essential for reproduction, and physicians often use it to stimulate as many follicles as possible in a woman’s ovaries, so a larger number of eggs can be recovered for IVF treatment.

Ireland said evaluating the impact and mechanisms of excess FSH levels on ovarian function and egg quality could lead to developing better, assisted reproductive technologies in the future, something the team will also try to accomplish as part of its research.

According to 2014 data reported by the Centers for Disease Control & Prevention, 33% of women who actually went through fertility treatments using their own eggs were able to get pregnant but only 27% had a live birth.

“If we can improve the fertility response rate of cows that have these small ovarian reserves, our findings could be useful for clinicians to use and may eventually lead to more successful pregnancies ending in live births in women,” Ireland said.

Genetic fitness

At the recently concluded annual meeting of the American Association of Swine Veterinarians in Denver, Colo., Iowa State University professor emeritus Dr. John Mabry discussed the economic impact of fitness traits in post-weaning pigs and sows in lieu of genetic improvement in litter size and leanness.

He noted that while over the past 30 years the swine industry has seen dramatic increases in litter size and reductions in backfat, in making genetic improvement, the industry needs to be aware of any possible "correlated responses."

For example, as litter size has increased, it has exceeded the uterine capacity of the sow, leading to more low-birthweight piglets that can have lower survivability to weaning and those that make it to weaning often have substandard weaning weights.

Another example Mabry gave was as backfat has decreased and lean meat percentage has increased, there is a greater percentage of grower/finisher pigs that are more fragile with more structural problems.

Mabry said these negative correlated responses in fitness traits exert an economic impact with higher sow and pig mortality, higher sow culling rates and an increased percentage of substandard market hogs.

He concluded that the industry does need to increase reproduction rates but needs to look at the entire system. Do extra pigs cost more in reduced performance? Selection systems need to account for structural traits and include preweaning mortality and percent sub-standard market hogs, he added.

For the commercial pork producer, it is logical to focus the genetic program toward one that will maximize long-term profits at their farm rather than chase short-term improvements in targeted traits of current interest, he said.