Explain the connection between shortening day length and the onset of oestrous in sheep. - Leaving Cert Agricultural Science - Question 10 - 2009
Question 10
Explain the connection between shortening day length and the onset of oestrous in sheep.
Worked Solution & Example Answer:Explain the connection between shortening day length and the onset of oestrous in sheep. - Leaving Cert Agricultural Science - Question 10 - 2009
Step 1
Connection between seasonal breeding and light levels
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Sheep are known as seasonal breeders, specifically breeding in autumn or winter, typically from August to December. This breeding season is closely linked to the natural shortening of day length during these months.
Step 2
Role of light in hormonal regulation
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The decline in light levels acts on the sheep's pituitary complex, which is regulated by the hypothalamus and the pineal body. As daylight decreases, these glands detect the reduction in light.
Step 3
Hormonal stimulation
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
In response to the shorter days, the pituitary gland stimulates the release of Follicle Stimulating Hormone (FSH), which in turn stimulates the ovaries. This leads to an increase in estrogen production, ultimately inducing the oestrous cycle in sheep.
Join the Leaving Cert students using SimpleStudy...
