SA reproduction Flashcards
when does the bitch begin cycling?
6-18 months
what is the average oestrous cycle of a bitch?
6 months
what are the stages of oestrous?
proestrus (9 days)
oestrus (9 days)
dioestrus (60 days)
anoestrus (100-150 days)
what stages of the oestrous cycle is described as in-heat?
proestrus and oestrus (21 days)
what are the clinical signs of proestrus?
serosanguinous vulval discharge
vulva swelling
attract but reject males
what are the clinical signs of oestrus?
reduced vulval swelling
serous/brown vulval discharge
accept male
what is the most common stage of the oestrous cycle to see pyometras?
diestrus
what is follicular development during proestrus stimulated by?
FSH and LH pulses
what happens to oestrogen during proestrus?
rises throughout then peaks at the end
what does the peak of oestrogen at the end of proestrus trigger?
LH surge
what does the LH surge at the end of proestrus trigger?
ovulation
how long after the LH surge does ovulation occur?
24-48 hours
what hormone begins to rise after the LH surge?
progesterone
what hormone is dominant in diestrus?
progesterone
what causes vulval swelling during proestrus?
oestrogen
how is vaginal cytology carried out?
moistened cotton swab aimed dorsally into the vagina
what type of cells are looked at during vaginal cytology?
cornified
what is cornification?
process of cells moving from deep to superficial epithelium
what is the appearance of a parabasal cell?
large nuclei and smooth edges
what are the cornified cells in vaginal cytology?
superficial and anuclear
what is the appearance of an intermediate cell?
smaller nucleus with slightly irregular cell shape
what are the findings on vaginal cytology during proestrus?
parabasal and intermediate cells (slowly increasing)
RBCs and neutrophils
what are the findings on vaginal cytology during oestrus?
100% anuclear and superficial cells (cornified)
what are the findings on vaginal cytology during dioestrus?
drop to 50% cornified cells
neutrophils
what hormone is used for oestrus detection in dogs?
progesterone
how does the vaginal mucosa change as oestrogen rises during proestrus?
becomes oedematous
how does the vaginal mucosa appear when there is a rapid oestrogen decline in oestrus?
oedema deflates causing wrinkles
what type of breeders are cats?
seasonal polyoestrus induced ovulators
what is the additional stage of the oestrous cycle in cats?
interoestrus (if not induced to ovulate)
what are the possible risks of neutering female dogs?
intra-op complications ovarian remnant syndrome transitional cell carcinoma urethral sphincter mechanisms incompetence (USMI) osteosarcoma
what is urethral sphincter mechanisms incompetence (USMI)?
reduction in urethral closure pressure (can happen years after)
how can urethral sphincter mechanisms incompetence (USMI) be treated?
propalin
estriol
what does ovarian remnant syndrome lead to?
continued secretion of reproductive hormones (oestrus behaviour)
uterine stump pyometra
neoplasm
when is the best time to spay small breed dogs?
before first season (6 months) - after they’ve stopped growing
when is the best time to spay medium breed dogs?
before first season (6 months) - after they’ve stopped growing
what are possible complications of castrating dos?
surgical risk neoplasia transitional cell carcinoma worsening behaviour osteosarcoma
what is the most common bacterial isolated from canine pyometra?
E. coli
what effects does progesterone have on the uterine tissues that predispose to pyometra?
endometrial hyperplasia cervical closure reduced myometrial contractility hormone sensitivity (positive feedback loop) decreased WBC function
what are two common presentations of severe pyoemtra?
hypovolaemic shock distributive shock (blood pumped away from organs)
what are the clinical signs of distributive shock?
tachycardia
red MM and rapid CRT
good pulse
what are possible changes in WBC count seen with pyometra?
leucocytosis - response to infection
leucopenia - increased consumption (poor prognosis)
what is a common finding on biochemistry in pyometra cases?
azotaemia (normally pre-renal)
what is the main cell type found on vaginal cytology of pyometra cases?
degenerate neutrophils (intracellular bacteria)
when may medical management be used for pyometra cases?
young animals to avoid surgery when cycling
delay surgery until animal is stable
what precautions need to be taken with a pyometra surgery?
appropriate anaesthetic (hypovolaemic) friable tissue pack cavity with swabs incase of spill (flush)
what are the aims of medically managing pyometra?
minimse progesterones effect
eliminate uterine infection
remove uterine content (myometrial contraction)
what drugs can be used for medical treatment of pyometra?
prostaglandins dopamine agonists receptor blockers (aglepristone)
what should the owners be aware of if medically treating pyometras?
cost
fertility issues
what is the cause of stump pyometra?
ovarian remnant
what are the clinical signs of ovarian remnant syndrome?
oestrus behaviour
stump pyometra
what test can be done to test fr ovarian remnant syndrome of there are signs of oestrus?
give GnRH and measure oestradiol before and after
what can be tested for in blood to confirm ovarian remnant syndrome?
anti-mullerian hormone and progesterone
what are the clinical signs of pseudopregnancy?
lactation
behavioural signs
inappetence
what are non-medical ways of managing pseudopregnancy?
increase exercise remove toys (if mothering)
what can be used to medically treat pseudopregnancy?
cabergoline
what should not be used to treat pseudopregnancy?
spaying (drop in progesterone sustains pseudopregnancy)
what is used to treat misalliance medically up to day 45 post mating?
aglepristone (2 doses 24 hours apart)
how can misalliance be treated surgically?
ovariohysterectomy (same as pyometra)
what is done to treat juvenile vagintits?
self limiting (no antibiotics)
what is the gestation length of a dog from the LH surge?
65 days
what is the gestation period of a dog from ovulation?
63 days
what is the gestation period of a dog from mating?
57-73 days
how far into gestation can ultrasound be used for pregnancy diagnosis?
day 25
when can heart beat of a puppy be detected on ultrasound?
day 25
what are the limitations of using ultrasound for pregnancy diagnosis?
can’t foetal count
can see false negatives (too early)
how far into gestation can radiography be used to confirm pregnancy?
day 45 (ossification)
how long is stage 1 of parturition?
6-36 hours
what happens to hormones during stage 1 of parturition?
progesterone drops and prolactin rises
what are the clinical signs of stage 1 of parturition?
temperature drop
restless, anxious
nesting
milk production
what marks the start of stage 2 of parturition?
rupture of allenochorion of fist puppy
what is stage 3 of parturition?
expulsion of placenta
what are signs of foetal distress?
meconium
green vaginal discharge (placental detachment)
what are examples of maternal factors causing dystocia?
primary/secondary inertia physical obstruction (narrow pelvis...)
what are examples of foetal factors causing dystocia?
oversized foetus
malpresentation
malformation
what is primary uterine inertia?
failure to start stage 2 of labour (no contractions/puppies)
what is secondary uterine inertia?
failure to progress through second stage of labour (prolonged contractions)
what can cause secondary uterine inertia?
lack of oxytocin
lack of glucose/calcium
maternal exhaustion
what considerations are important when anaesthetising a bitch for caesarian?
higher oxygen demand
higher CO
risk of venous obstruction from uterus
hypothermia
should pre-mediaction be given for caesarians?
no (might have to but use something reversible for pups)
what are the characteristics wanted in an induction drug for caesarian?
rapid onset
rapidly metabolised
titrated to effect
what two drugs can be used to induce caesarians?
propofol
alfaxalone
wha positions should a patient be in when carrying out a caesarian?
elevate thorax (drop abdominal content away from diaphragm)
what drugs can be used to deliver systemic analgesia for caesarians?
NSAIDs
opioids
paracetamol
(give after procedure)
why should care be taken when using opioids for analgesia during caesarians?
passes into the milk (give after procedure)