USA Biology Olympiad (USABO) Practice Exam

What is a likely effect of high temperatures on the reproductive capabilities of a dog?

1. Increased fertility

2. Sterility

3. Delayed breeding cycles

4. Enhanced libido

The correct answer is: Sterility

High temperatures can have significant effects on the reproductive capabilities of dogs, and in this context, sterility is a likely effect. Elevated temperatures can lead to impaired sperm production in males as the testes are particularly sensitive to heat. Sperm development requires a cooler environment than the body’s core temperature, and when exposed to excessive heat, it can result in reduced sperm count and motility, ultimately affecting fertility. In females, high temperatures may disrupt hormone production and ovulation cycles, potentially leading to issues with breeding. Extreme heat can also affect overall health, which is critical for successful reproduction. While high temperatures might not directly cause permanent sterility, they can significantly impair reproductive function and the ability to conceive, warranting concern about a temporary or longer-lasting impact on fertility.