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
There’s a new way of neutering, and it’s slowly making its way across the country.
This weekend’s stop on the national tour is the New Orleans area, where local veterinarians and animal advocates will get a chance to learn more about “Zeutering,” which involves an injection into the testicles of a new zinc-based drug, called Zeuterin.
(Warning to the faint of heart, or the faint of scrotum: The process is shown in the video above.)
Zeuterin has been approved by the FDA for use in dogs from 3 to 10 months old, and Ark Sciences says it anticipates the agency will soon approve it for use in dogs of all ages.
For now, the company, and its nonprofit branch, Ark Charities, Inc., are demonstrating the product and training veterinarians in its use in select cities across the country.
In Ponchatoula this Sunday, veterinarians will have a chance to learn more about the treatment at a presentation sponsored by Ark Charities, Inc. and Friends of the Shelter, an organization based in Hammond, according to the Times-Picayune. At least eight area veterinarians will participate, and gain certification to administer the compound.
The shot consists of zinc gluconate and arginine and is adminstered to the testicles, killing sperm-producing cells and reducing testosterone by about 50 percent. Testicles, while shrunk, remain visible. Because a Zeutered dog still has his testicles, each dog injected receives a tattoo on his inner thigh, indicating he has received the procedure.
Unlike traditional neutering, general anesthesia is not required — just a mild sedative. No slicing is involved either, meaning quicker recoveries, less risk of infection and much less expense. It costs about $20.
Zeuterin was used in Japan to control the dog population in abandoned areas after the 2011 earthquake and tsunami, and it also met with success in controlling feral dogs in the Philippines.
In the first U.S. clinical study, involving 270 dogs, only 1 percent had adverse reactions to Zeuterin, and half of those were attributed to improper administration.
Zeuterin lowers testosterone rates 41 percent to 52 percent compared to neutering, which eliminates testosterone entirely.
Posted by John Woestendiek May 17th, 2013 under Muttsblog, videos.
Tags: animal control, animals, branding, control, demonstrations, dog, dogs, humane societies, injection, male, neuter, neutering, new orleans, non-surgical, overpopulation, pets, population, population control, promotion, rescues, shelters, shrink, shrinkage, surgery, testicles, testosterone, veterinarians, veterinary, zeuter, zeuterin, zeutering, zinc