Feline Theriogenology Flashcards
puberty in cats; when, what its influenced by
◦ Pubertal estrous = between 4 – 12mnts of age
◦ Influenced by time of year & body condition
◦ Usually when reaches 80% of adult body weight
what type of ovulators are cats
◦ Seasonal, polyestrous, induced ovulator
◦ Induced ovulators = require copulation to initiate the LH surge
when does the estrus cycle occur
◦ Estrus cycles occur at 4-30 day intervals in cats exposed to constant daylight (14 hrs)
prolonged anestrus in cats
◦ Prolonged anestrus = decreasing or short day lengths (autumn)
feline estrous cycle begins vs peak
◦ Season begins Jan-Feb = peak is Feb-March
what can be used to stop intact queens from cycling
melatonin
what happens during proestrus; behaviour, estrogen level, length
◦ Only observed in minority of queens = most enter estrus directly
◦ Males are attracted but females are non-responsive
◦ Continuous rubbing of head and neck
◦ Short lived - if it occurs at all (0.5-2 days)
◦ Increase in estrogen
what do we see with behavioural estrus
◦ Crouching in the front with hind end elevated = lordosis
◦ Threading with hind legs, deviation of the tail = vulva exposed for mating
◦ Vocalize, more head rubbing, affectionate behavior
when does estrus occur
◦ Occurs during peak follicular activity & estradiol concentrations
what stage of the cycle are cats receptive to mating
estrus
how can you detect estrus (4)
◦ Estrus behavior
◦ Vulvar labia will only slightly increase in size compared to the bitch
◦ Mucoid discharge can be seen – won’t see bloody vaginal discharge
◦ Vaginal cytology = see cornification as in the bitch (Not useful to tell you when to breed)
what are the steps of mating
◦ Nose to nose
◦ Investigate perineal area – Flehmen
◦ Grab neck – very important
◦ Mount
◦ Threading – slides down the female
◦ Pelvic thrusting -> intromission -> ejaculation -> 20 seconds
◦ Pulls away quickly -> avoid being struck by female
◦ Queen licks vulva, rubs on the floor, vocalizes = “after reaction”
duration of estrus
◦ Variable
◦ Average: 5.8 days (Range: 2-19 days)
LH surge; induced by, what magitude depends on, when ovulation occurs after
◦ Induced by copulation but requires hypothalamic/pituitary exposure to estrogen
◦ Needs to be in heat
◦ Magnitude of LH surge increases with number of copulations
◦ Induction of ovulation occurs 29-40hrs later -> ovulation occurs 24-48hrs post coitus
does copulation cause ovulation
copulation causes the LH surge = NOT ovulation
when does diestrus occur
◦ Follows estrus in the queen that has ovulated (induced or spontaneous ovulation)
how long does diestrus last
Lasts approx. 40 days in pseudopregnant queen
◦ Note: pseudopregnancy is often not visible externally in comparison to bitches
what ends diestrus
◦ Ends with luteolysis (mechanism unknown in the cat)
what hormone is dominant in diestrus
◦ Progesterone dominated -> CLs
◦ Progesterone starts to rise from baseline within 24 hrs post-ovulation
what is the interestrus interval; what happens during it, length
◦ Period that follows one estrus and precedes the next in queens that have not been induced to ovulate
◦ Estradiol drops
◦ No sexual behavior or receptivity is present
◦ Length is variable
optimal breeding time
◦ Between 1.5-7 years of age
why do we need to bloodtype cats
◦ Important for prevention of neonatal isoerythrolysis
◦ Should blood type all cats used in breeding colony/program
◦ Purebred cats (British Shorthair, Devon & Cornish Rex) = more type B
breeding of female in males territory
◦ Ideally don’t breed day 1 of estrus
◦ Then starting on day 2, breed 3-4x daily until end of estrus, if possible (at least over 2 day
period)
type of placentation
◦ Endotheliochorial, zonary
◦ No obvious marginal hematomas
