A common human diabetes medication may also allow chickens to lay more eggs by improving their metabolic health say researchers from Pennsylvania State University
Why it matters: If broiler breeder hens stay fertile longer, farmers may be able to replace flocks less often. This could have animal welfare and efficiency benefits.
Metformin is usually prescribed in humans for type 2 diabetes. It may also be used to treat polycystic ovary syndrome (PCOS) — a hormonal disorder that affects women and can cause irregular periods and infertility, among other symptoms. Metformin may be prescribed to increase insulin sensitivity and reduce excess hormones.
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In a study published in 2023, Penn State researchers found that broiler breeder hens stay fertile and produce eggs longer if given a small daily dose of metformin.
Broiler breeder hens, which produce hatching eggs for meat chickens, rapidly decline in productivity as they age. This drop in fertile egg production resembles PCOS in humans, the university said in a May 7 article.
When given metformin, the hens laid more fertile eggs, had lower body fat and showed healthier reproductive hormone levels than those not given the drug.
This suggested metformin improved the hens’ ovarian function, said Ramesh Ramachandran, a professor of reproductive biology in the university’s College of Agricultural Studies.
Research published this year showed the drug “switched on” several genes related to producing yolk protein in the liver and stabilizing blood sugar. It also “switched off” genes linked to fat buildup.
“Essentially, metformin helps older hens stay metabolically healthier, which lets them keep producing eggs well beyond their usual decline,” said researcher Evelyn Weaver.
By extending egg production in broiler breeder hens, farmers may not need to replace flocks as often. This would have efficiency and animal welfare benefits, the researchers said.
Metformin is quickly metabolized and there’s no risk of it entering the human food supply, Weaver said.