North American Veterinary Licensing Examination (NAVLE) Practice Test

In felines, particularly domestic cats, estrus can occur in recurring intervals of approximately 2 to 3 weeks, especially when there is no male present. This phenomenon is referred to as "seasonal polyestrus." Unlike some other species, such as dogs, where the estrous cycle involves a distinct proestrus, estrus, metestrus, and anestrus, cats can continue to enter estrus repeatedly throughout their breeding season if they are not mated. The absence of a male triggers the female to go through cycles of estrus in this relatively short timeframe, allowing the potential for mating when a male is available.

In contrast, the reproductive cycles in dogs are more spaced out, with a common cycle approximately every six months. Horses and sheep also have specific breeding seasons and patterns where estrus does not typically recur in such short intervals without the presence of a male. Therefore, the behavior of cats regarding their estrous cycles is unique and best explains why they are the species identified in this context.