monestrous

biology

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June 30, 2026

Quick Summary

Monestrous refers to female mammals that experience estrus, or heat, only once per year or breeding season. Estrus is the period when a female mammal is receptive to mating. This reproductive cycle is regulated by hormones from the pituitary gland and ovaries.123

Animals that are monestrous have a long anestrus, which is a non-reproductive period, between their breeding seasons. This contrasts with polyestrous animals, which have multiple heat cycles within a single breeding season if they are not impregnated. Dogs are an example of a monestrous species.32

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estrus
, dogs) are monestrous, having only one heat during a breeding season. Others (e.g., ground squirrels) are polyestrous: if not impregnated, they will come into heat repeatedly during the breeding season. Males can recognize a female in heat by smell; certain substances (pheromones) are secreted only at this…
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, dogs) are monestrous, having only one heat during a breeding season. Others (e.g., ground squirrels) are polyestrous: if not impregnated, they will come into heat repeatedly during the breeding season. Males can recognize a female in heat by smell; certain substances (pheromones) are secreted only at this…
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mammal
Estrus and other cycles
…once a year are termed monestrous and exhibit a long anestrus; those that breed more than once a year are termed polyestrous. In many polyestrous species the estrous cycle ceases during gestation and lactation (milk production), but some rodents have a postpartum estrus and mate immediately after giving birth.
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…once a year are termed monestrous and exhibit a long anestrus; those that breed more than once a year are termed polyestrous. In many polyestrous species the estrous cycle ceases during gestation and lactation (milk production), but some rodents have a postpartum estrus and mate immediately after giving birth.
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