Abstract
Most sheep are seasonal estrus, and they breed in autumn when the days get shorter. Seasonal estrus is an important factor that affects the productivity and fertility of sheep. The key point to solve this problem is to explore the regulation mechanism of estrus in sheep. Therefore, in this study, transcriptomic sequencing technology was used to identify differentially expressed mRNAs in the hypothalamus, pituitary and ovary of Small Tail Han sheep (year-round estrus) and tan sheep (seasonal estrus) among luteal, proestrus and estrus stages. There were 256,923,304,156 mRNAs being identified in the hypothalamus, pituitary and ovary, respectively. Functional analysis showed that the photosensor, leucine and isoleucine biosynthesis pathways were enriched significantly. It is speculated that photoperiod may initiate estrus by stimulating the corresponding pathways in hypothalamus. ODC1, PRLH, CRYBB2, SMAD5, OPN1SW, TPH1 are believed to be key genes involved in the estrogen process. In conclusion, this study expanded the database of indigenous sheep breeds, and also provided new candidate genes for future genetic and molecular studies on the seasonal estrus trait in sheep.
Highlights
The life activities of animals are greatly affected by seasonal changes
Tan sheep and Small Tail Han (STH) sheep were selected from the same breed protection farm in Ningxia Autonomous Region, China, and those raised under similar conditions with free access to water and food in natural lighting
The results showed that sheep of the same breed showed similar expression patterns in the same tissue
Summary
A common reproductive strategy among mammals living in a seasonally fluctuating environments is the restriction of breeding activity to an optimal time of year [1]. This helps to ensure that the offspring can be born in the best season for survival and growth [2]. Are estrous and mating in spring and summer when the sunshine is getting longer Those seasonal breeding animals can only estrus and ovulate during the estrous seasons. These animals called seasonal multiple estrus, such as horses, donkeys, sheep and goats. Seasonal breeding is the main limiting factor to restrict the balanced supply throughout the year [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
