Throughout the 20th century, scientists have documented a frightening trend in the human race. Sperm counts have been steadily declining in men to the tune of 1% per year, for over fifty years. Plenty of possible culprits have been blamed for this such as pesticides, polycarbonate plastics, oestrogen in the water from the contraceptive pill, lifestyle choices, and more recently, even cell phones have been thought to be a contributing cause.
However, no study has conclusively proven any of these theories with 100% certainty. Fortunately, the scientific community may have just found a compelling new lead in this mystery, and it doesn’t involve humans. Apparently, dogs have also been experiencing a decline in sperm quality that has been ongoing for nearly 30 years, according to researchers at the University of Nottingham.
Richard Lea, who led the study on this trend, has said that “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.”
The study involved collecting semen samples from dozens of dogs every year, for 26 years. The researchers found that their sperm motility declined 2.5% per year between 1988 and 1998, and at 1.2% per year between 2002 and 2014. Genetic conditions were ruled out as a cause for this decline.
Richard Lea added that “While further research is needed to conclusively demonstrate a link, the dog may indeed be a sentinel for humans – it shares the same environment, exhibits the same range of diseases, many with the same frequency, and responds in a similar way to therapies.”