Pregnancy Failure in Companion Animals

Question 1

Define proestrus

Answer 1

“heat”
behaviour changes into sexual receptivity
lasts 9d
follicular growth and CL regression
external evidence (vulval oedema, hyperaemia and bloody discharge)

Question 2

Define oestrus

Answer 2

the mating period where the bitch will accept the hound
lasts 9d
ovulation occurs in this phase
follicular growth and oestrogen produced

Question 3

Define dioestrus

Answer 3

period after ovulation and oestrus, either the patient is pregnant or the CL is maintaining increased progesterone
lasts 60d
the CL is present on the ovary and secretes progesterone
see mammary gland hyperplasia, constricted cervix, scant and sticky secretions, pale mucosa

Question 4

Define anoestrus

Answer 4

nothing is happening
90-150d
follicular development is minimal and CL has regressed and is non-functional

Question 5

Differences between bitch and queen oestrus cycle

Answer 5

bitch 2.5m, queen 17-20d
ovulation induced in queen
monoestrus dogs, seasonally polyoestrus cats

Question 6

Reasons for pregnancy failure in companion animals

Answer 6

failure to get pregnant
failure to ovulate
failure to conceive
failure of pregnancy

Question 7

Reasons for failure to ovulate

Answer 7

absence of oestrus
abnormal cycle (prolonged anoestrus is common due to owners missing seasons and dogs cleaning up after themselves)

Question 8

Reasons for failure to conceive

Answer 8

failure to mate
false oestrus
the tie not happening
anatomical abnormalities
DSDs
inflammation of the uterus
neoplasia
infertile males
incorrect timing of mating

Question 9

Define vaginal hyperplasia and explain why it is a problem

Answer 9

hyperplasia of the vagina
a little is normal in response to high oestrogen
it can vary all the way to a large mass, obstructing the lumen and preventing copulation

Question 10

Reasons for failure of maintaining pregnancy

Answer 10

resorption
abortion
mummification
maceration
stillborn

Question 11

Maternal causes for failure of pregnancy

Answer 11

inflammation (hostile environment)
infection (Brucella canis, Toxoplasma gondii, Neospora caninum, CHV1)
metabolic (pregnancy toxaemia, inadequate CHO)
endocrine (premature parturition and hypolutoideism)
toxins/drugs

Question 12

Diagnosis of abortion in companion animals

Answer 12

lab exam on aborted material
- gross
- histo
- virology
- microbiology
- toxicology
serum sent for serology
vaginal discharge sent for virology
imaging of the repro tract through ultrasound