Declining sperm quality has been identified in 5 separate breeds of dogs. The dogs tested are from a center in England that breeds, raises and trains dogs for as service animals over a 26 year period. This allowed for a fairly controlled population of subjects compared to other possible studies. During this time, sperm motility has declined 30% in all the breeds.
The dogs who share our homes are exposed to similar contaminants as we are,” said Richard G. Lea, an associate professor of reproductive biology at the School of Veterinary Medicine and Science at the University of Nottingham. “So the dog is a sentinel for human exposure,” added Dr. Lea, the study’s principal investigator.The most frightening part is that the testicular tissue of the dogs was tested and concentrations of chemicals that had been common in electrical transformers and paint were located. The environment that the dogs are living in is the same that the human race is. For 70 years there has been a studied decline in human sperm quality along with slight increases in rates of testicular cancer and genital tract abnormalities. There is not a direct correlation between the two, but the fact that they are both declining has sparked the interest in scientists even further.
http://www.nature.com/articles/srep31281
