Whether or not the ewes can reproduce normally depends on whether or not the estrus is normal. Normal estrus refers to a cyclical activity that occurs when the ewes reach sexual maturity. This periodical activity is accompanied by changes in the ovary, reproductive tract, mental state, and behavior of the ewe. 1: seasonal The sheep are short-lived animals, and they are always estrus in autumn and winter. This is the result of long-term natural selection. In wild conditions, sheep are always selected to facilitate the survival of the lambs. In the autumn and early winter, the ewe's condition is good, and the mating gestation is favorable. After the lambs are sucked and weaned, the external environmental conditions are favorable to the growth and development of the lambs and safety. We spend the following winter. Therefore, long-term natural selection makes the sheep have the properties of seasonal breeding. However, the intervention of artificial selection makes this property change to varying degrees. At the same time, it is also the result of adapting a certain species to the corresponding ecological environment, such as China's small tail Han sheep, Hu sheep, white goats and other regional breeds, the introduction of Suffolk The cultivars such as Charolais and Boer goats have the characteristics of four-season estrus. However, even if the estrus of these species is relatively concentrated in the spring and autumn. Hot summer and harsh winter are not conducive to male and female breeding. 2: Repeatability In other words, sheep and goats have repeated estrus cycles during their breeding season and have multiple estrus performances. Because the ewes from the previous estrus to the next estrus interval (called the estrous cycle) are 17d (14d-19d) in sheep and 21d (18d-24d) in goats, therefore, it is possible to repeat estrus even if the estrus is only in autumn. , not to mention the estrus of the four seasons. 3: Staged In each estrus cycle, the ewes have phases in their internal reproductive hormones, ovaries, reproductive tracts, or external changes in performance and behavior. Can be divided into pre-estrus, estrus, late estrus and intercourse. The duration of estrus is often referred to as the duration of estrus. The duration of estrus in sheep is generally around 30h and goats are from 24h to 38h. Most ewes ovulate at the end of their estrus. The time for mature eggs to survive in the fallopian tube is 4h-8h, and the optimal time for the sperm and egg to work is within 24h. Therefore, timely observation of estrus stage changes in estrus, and determine the appropriate timing of mating is an important prerequisite for improving the conception rate. Picc Line Cover,Picc Line Sleeve,Picc Line Shower Cover,Picc Line Waterproof Cover Wenzhou Celecare Medical Instruments Co.,Ltd , https://www.celecaremed.com
Ewe estrus characteristics