Warning: Dog Food May Lessen Male Dogs' Fertility, Study Shows

Next time you visit the pet store, think twice on buying dog food. Researchers reveal that what you're feeding your dog may greatly affect their fertility.

According to a study published in the journal Scientific Reports, there has been a dramatic 30 percent decline in sperm quality among male dogs in the past 26 years, specifically those belonging in the breeds Labrador retriever, golden retriever, curly coat retriever, border collie and German shepherd.

The researchers link the poor sperm quality to environmental contaminants in dog foods, even puppy chow formulation, New York Times reports.

Richard Lea, a reproductive biology specialist at the University of Nottingham's School of Veterinary Medicine and Science, and his team examined various brands of dog food (wet and dry) sold in the market. They found out that these products contains harmful chemicals such as PCBs and diethylhexyl phthalate (DEHP), which are also found in the dogs' semen.

"This is the first time that such a decline in male fertility has been reported in the dog and we believe this is due to environmental contaminants, some of which we have detected in dog food and in the sperm and testes of the animals themselves," said Lea via Science Daily.

The dogs who were studied also exhibited cryptochidism, a genital disease where one or both testes is absent from the scrotum.

The team is still unsure how these chemicals got into the dog food products, but notes that they must have been contaminated from the product's packaging.

"This raises the tantalising prospect that the decline in canine semen quality has an environmental cause and begs the question whether a similar effect could also be observed in human male fertility," Lea said.

To learn more about what you're feeding your dogs, check out the video below.