Small animal breeding Flashcards
Where do we deposit semen in dog AI
In the fornix
What route do we take into the vagina into the dog
In a small bit then directly up then continue forwards
NB: be aware of the clitoral fossa; can get pipette stuck there and mistakenly inseminate there
Bitch repro tract basics
2 ovaries; 2 uterine horns; 1 uterine body; cervix, vagina, vestibule
Why is it normal to see cavitation on some CLs
Because multiple follicles ovulating over course of a few hours; will see CLs at various stages of the luteal phase
- Have fluid in them early one
Two important features in dog sexual anatomy
Os penis = bone in penis; keeps rigid even when not erect; must be careful not to damage
Bulbus glandis = vascularised structure that wraps around base of penis; creates ‘copulatory lock’ to stop semen getting out
What can we use to tell if a cat has been castrated/ still has active androgen production
Look for spikes on penis; need activate maintenance do disappear within weeks without
What is different about male cat anatomy vs dog
Penis faces backwards
Spikes on penis for stimulation to induce ovulation
What age do female dogs reach puberty
Small dogs: 6-8 months
Large dogs: 12 months
Giant breeds (+ greyhounds, wolf hounds): 18-20 months
When do spermatozoa first appear in dog ejaculate
7-9 months
What age do male dogs reach puberty
Small: 6 months
Large: 12 months
Process of testes descending in male dogs
Born with them intra-abdominally
Move through inguinal canal by 3-4 days after birth
Descend by 2 weeks after birth
Final position in scrotum at 35 days
BUT can take longer
Puberty in queens
VERY weight dependent
See at 6-9 months
How is puberty onset in cats altered by being long day breeders
By photoperiod; may reach right AGE for puberty in winter BUT won’t achieve it until SPRING
Specific breed exceptions to normal puberty times in cats
Oriental breeds: reach puberty very early
Long haired and manx breeds reach it later (11-21 months)
Which breed of dog has retained seasonality in breeding
Bassen G
What is the oestrus cycle in the bitch like
Non-seasonally mono-oestrus
> Inter-oestrus interval variable; around 6-7 months
Exceptions in inter-oestrus interval in dog breeds
German shepherds and rottweilers: inter-oestrus interval just 4-5 months
Tibetin mastiff: cycles once per year
Reproductive cycle in the bitch; brief summary
Anoestrus: get small peaks of FSH but not enough to stimulate growth
- THEN: start to get LH in circulation which allows follicles to mature
Enter proestrus: follicles are producing oestrogens; get blood discharge from vagina and vulva enlargement (NOT RECEPTIVE)
- Then discharge gets paler and vulva less oedematous
Estrus: standing heat; will put tail to side to expose genitalia
After ovulation: enter luteal phase (dioestrus) = sexual quiescence
Which breeds have lots of vulval swelling; and what is normal
Normal is 2-3 x dioestrus size
Boxers show lots of swelling
What is significant about progesterone production in the bitch
Granulosa cells lining follicle start to produce progesterone before ovulation; so can use this to predict the timing of ovulation
WHy does fertilisation in the bitch not happen until 48-72 hours after ovulation
Because the oocyte that ovulates is IMMATURE; still in meiosis 2 i.e a primary oocyte
Takes time to complete this to be competent for fertilisation
How long is the luteal phase is a non-pregnant bitch
Almost identical to in a pregnant bitch i.e 45-70 days (~2 months)