I can't find a study that addresses your specific question, Mike, but here's what I did find out about decreased sperm counts.
Factors that can affect the number of spermatozoa per ejaculate include age, degree of arousal, testicular size, and frequency of ejaculation. Healthy dogs kept in new surroundings may show a temporary, reversible drop in sperm count. Dogs living in warm environments may experience transient drops in sperm counts. There are also some pathological conditions that can result in reduced sperm counts, including obstructions, retrograde ejaculation (ejaculation into the bladder) and testicular degeneration. In some breeds, testicular degeneration appears to be an autoimmune process affecting previously fertile, middle-aged dogs. Additionally, some systemic diseases, such as hypothyroidism can impair fertility.
Here are some links to discussions of fertility problems in male dogs.
Disorders Affecting Fertility in the Male Dog (P. Davol)
Infertility--Male Dogs (The 5-Minute Veterinary Consult)
Male Infertility
Reproductive Problems in Male Dogs (scroll down)
Additional reference: Freshman JL: Clinical management of the subfertile stud dog. Vet Clin North Am Small Anim Pract 31:2, 2001, p 259
[ March 14, 2004, 05:57 PM: Message edited by: Betsy Iole ]
Factors that can affect the number of spermatozoa per ejaculate include age, degree of arousal, testicular size, and frequency of ejaculation. Healthy dogs kept in new surroundings may show a temporary, reversible drop in sperm count. Dogs living in warm environments may experience transient drops in sperm counts. There are also some pathological conditions that can result in reduced sperm counts, including obstructions, retrograde ejaculation (ejaculation into the bladder) and testicular degeneration. In some breeds, testicular degeneration appears to be an autoimmune process affecting previously fertile, middle-aged dogs. Additionally, some systemic diseases, such as hypothyroidism can impair fertility.
Here are some links to discussions of fertility problems in male dogs.
Disorders Affecting Fertility in the Male Dog (P. Davol)
Infertility--Male Dogs (The 5-Minute Veterinary Consult)
Male Infertility
Reproductive Problems in Male Dogs (scroll down)
Additional reference: Freshman JL: Clinical management of the subfertile stud dog. Vet Clin North Am Small Anim Pract 31:2, 2001, p 259
[ March 14, 2004, 05:57 PM: Message edited by: Betsy Iole ]
