Researchers at the University of Nottingham say they’ve documented a serious decline in the fertility of male dogs — and suggest that dog food or environmental causes may be to blame.
In a study spanning 26 years, researchers tracked the sperm motility levels of five different breeds — Labrador retrievers, golden retrievers, curly coat retrievers, border collies and German shepherds.
They took samples from between 42 and 97 dogs each year, according to the study, published in Scientific Reports.
Between 1988 and 1998, the team recorded a 2.5 percent decline in the amount of motile sperm per year. Between 2002 and 2014, this trend continued at a rate of 1.2 percent each year.
The researchers also found that male pups produced by dogs with declining sperm quality had an increased incidence of cryptorchidism, a condition where one or both of the testicles don’t descend properly.
The study suggests that the sperm quality may have been impacted by contaminants in dog food.
“We looked at other factors which may also play a part, for example, some genetic conditions do have an impact on fertility,” said Dr Richard Lea, leader of the study. “However, we discounted that because 26 years is simply too rapid a decline to be associated with a genetic problem.”
Dogs used for the study were all bred, raised and trained as service animals for disabled people at an unidentified center in England, according to the New York Times.
The scientists said that in addition to collecting samples throughout the study, they examined the testicles collected from dogs that had undergone castration.
Both showed environmental contaminants in high enough concentrations to affect sperm motility. These same chemicals were also discovered in various commercially available dog foods.
The researchers say the findings raise the question of whether a reported decline in human semen quality over the last 70 years could also be a result of environmental factors.
(Photos: Roscoe, a yellow Lab who was not involved in the study, and has no interest in the results, by John Woestendiek)
Posted by John Woestendiek August 12th, 2016 under Muttsblog.
Tags: animals, breeding, chemicals, contaminants, decline, dog food, dogs, food, health, motility, pets, quality, reproduction, research, semen, sperm, study, testicles, university of nottingham
Fifteen years ago, more than 400 people attended the national convention of the American Greyhound Track Owners Association.
This year’s convention, in Las Vegas, is expected to draw 120, the Las Vegas Sun reports — yet another sign that greyhound racing’s days are numbered.
The recession, competition from casinos, state legislatures increasing gambling taxes and public opposition to the sport have combined to threaten the future of dog racing, but the industry’s downfall can be traced to the 1980s and 1990s when state lotteries were introduced and casinos began to spread beyond Las Vegas and Atlantic City. Wagering on greyhound races in the United States declined from $3.5 billion in 1991 to $1.1 billion in 2007, according to the Association of Racing Commissioners.
The continued decline in dog racing has become even more painful for casino owners who are required to subsidize the tracks as a condition of operating casinos with slot machines.
As Roy Berger, executive vice president of the Dairyland Greyhound Park in Wisconsin, which closed last year, put it: “The product became an antique. We were an 8-track cassette store in a world of CDs.”
(Photo: American Greyhound Track Owners Association)
Posted by John Woestendiek March 23rd, 2010 under Muttsblog.
Tags: animal, association, casinos, closings, closures, convention, dairyland, decline, dogs, dwindling, fading, future, gambling, greyhound, greyhounds, las vegas, news, pets, shrinking, sports, track owners, tracks, wagering, wagers