Question

In mammals oestrus cycle is possible in seasonal breeders?give discription to satisfy the statement.

Answer 1

Seasonal breeders are animal species that successfully mate only during certain times of the year. These times of year allow for the optimization of survival of young due to factors such as ambient temperature, food and water availability, and changes in the predation behaviors of other species.[1] Related sexual interest and behaviors are expressed and accepted only during this period. Female seasonal breeders will have one or more estrus cycles only when she is "in season" or fertile and receptive to mating. At other times of the year, they will be anestrus, or have a dearth of their sexual cycle. Unlike reproductive cyclicity, seasonality is described in both males and females.[citation needed] Male seasonal breeders may exhibit changes in testosterone levels, testes weight, and fertility depending on the time of year.[2]
Seasonal breeders are distinct from opportunistic breeders, that mate whenever the conditions of their environment become favorable, and continuous breeders, like humans, that mate year-round.


Timing of seasonal breeding
The breeding season is when seasonal breeders reproduce. Various variables can affect when it occurs.[3] A primary influence on the timing of reproduction is food availability. Organisms generally time especially stressing events of reproduction to occur in sync with increases in food availability. This is not always true although, both because of the importance of other factors and the invalidation of this generalization. For example, in species reproducing at high latitudes, food availability before breeding is more important than availability during reproduction itself. Other factors can also be responsible. For example, species that are preyed upon frequently may time reproduction to occur out of sync with the peak in density of predators.