Sheep reproduction Flashcards
1
Q
What is the link between melatonin and cyclicity in sheep?
A
- Sheep = short day breeders -when melatonin increases in Autumn when the days get shorter
2
Q
how often do ewes ovulate when cycling?
A
*Every 16-18days
3
Q
How can reproduction be modified in sheep?
A
- Genetics
- Ram effect
- Day length
- Nutrition - flushing
- Melatonin
- Pharmacologically
4
Q
What can be used to synchronize ewes?
A
*Chronogest in sponges (progesterone)
*CIDR
*Prostaglandin - luteolysis + induce cycling
5
Q
What can be used to induce a lambing?
A
- 8ml dexamethasone injection - from day 140 after ram has been
6
Q
What is optimal BCS for ewes before mating?
A
- 3-3.5
- 2.5-3 in hill ewes
7
Q
What should you feed an ewe during gestation?
A
- Conception to 42 days = feed ewe maintenance only
- Days 42-90 = feed ewe maintenance + 2MJ/day
- Day 90-parturition = good nutrition essential (separate singles, twins, trips)
8
Q
What should you check in a pre-breeding ram examination?
A
- Physical exam - feet, brisket, caseous lymphadenitis
- Scrotal measurement + palpation
- Exteriorize + examine penis + vermiform appendage
- semen evaluation
- Libido testing
- Mating dexterity
- Serving capacity test
9
Q
What bacteria can cause epididymitis in UK rams?
A
- Actinobacillus seminis
- Haemophilus somnus
- Histophilus ovis
10
Q
What is scrotal mange, how is it identified + treated?
A
- Chorioptes bovis
- Identify by skin scrapings
- Tx = doramectin or DIazinon dip
