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
length of pregnancy
◦ 63-66 days, on average, from rise in P4
◦ 56-69 days from mating
what type of hormone is present during pregnancy
Progesterone dependent
◦ CLs
when does prolactin increase
Unlike in dogs – our prolactin only increases if pregnant – during the last
3rd of pregnancy and during lactation
pregnancy diagnosis (5) and when we can do them
Lack of estrus behavior
◦ Pseudopregnancy
◦ Some cats display estrus even while pregnant
Pinking of the nipples
◦ Occurs day 14-18
Abdominal palpation
◦ Day 25-30
Radiographs
◦ As with bitches
Ultrasound
◦ Easy by day 24-25
what happens in stage 1 of queening
Stage 1: cervical dilation/uterine contractions
◦ Restlessness is the most common sign
what happens in stage 2 of queening
Stage 2: passage of fetuses
◦ Kitten should be delivered within 15 mins once noted at vulvar lips
◦ Can take a very long time (interruptions by 10-12 hours are possible)
what happens in stage 3 of queening
Stage 3: passage of fetal membranes
is P4 drop a prereq for queening
Progesterone drops, but doesn’t necessarily have to = the drop isn’t a prerequisite for onset of parturition
◦ Don’t see a temperature drop like in bitches
how common is dystocia in cats
overall uncommon
what type of cats are at increased risk of dystocia
Purebred cats at increased risk
◦ Dolicocephalic and brachycephalic breeds = obstructive dystocia
what is the next step if there is no response to 2 oxytocin symptoms
c section
medical management of dystocia
Medical management -> oxytocin & calcium gluconate
◦ Cannot do manipulations à too small
◦ Same “rules” apply as in dogs (no obstructive dystocias, FHRs, etc.)
◦ “Quiet” place, left alone
surgical management of dystocia
Surgical management -> c-section
◦ Pre-medicate queen at last minute = kittens hard to resuscitate
most likely cause of dystocia in cats
uterine torsion
PP issues in cats (7)
Retained fetal membranes = metritis
◦ Usually queen is good at cleaning – don’t see much in terms of discharge
◦ If note discharge >7 days post-partum = investigate
Mastitis
Hypocalcemia
Agalactia
◦ Sometimes can’t express milk – kittens are still gaining weight & healthy – not truly agalactia
Uterine prolapse à more common in cats
SIPS
Poor mothering
when does cycling occur again after PP
Within 2 weeks post-partum = begin cycling again
◦ Anovulatory cycles; at least @ start of lactation = become ovulatory as
lactation decreases
specific disorders common in cats (5)
◦ Benign mammary hypertrophy/hyperplasia
◦ Mammary neoplasia
◦ Cystic endometrial hyperplasia (CEH)/pyometra complex
◦ Ovarian cysts
◦ Ovarian remnant syndrome
diagnosis of benign mammary hypertrophy/hyperplasia
◦ Signalment
◦ Clinical signs
◦ Progesterone assay
◦ Biopsy in older cats to rule out neoplasia
treatment benign mammary hypertrophy/hyperplasia
Removal of progesterone source
◦ OHE, aglepristone, luteolysis or abortion (spontaneous)
when (age) is benign mammary hypertrophy/hyperplasia common
Common in young cats (13 weeks- 2 years)
what hormone is benign mammary hypertrophy/hyperplasia dependent on
Progesterone dependent condition
◦ Occurs following ovulation (pregnant or not)
what treatment can cause benign mammary hypertrophy/hyperplasia
Can be seen in neutered males/spayed females if treated w progestins!
what does benign mammary hypertrophy/hyperplasia look like
See asymmetrical, firm, rapidly growing mammary tissue
◦ Can become bruised & ulcerated as they enlarge
3rd most common tumor in cats
Mammary neoplasia but still overall not seen a lot
risk of mammary neoplasia in intact female cats
Intact = 7x greater chance of developing mammary neoplasia
clinical signs of mammary neoplasia
◦ Older cats
◦ 1 or more masses (can have L and R mammary chain involvement)
◦ Are firm, can be well or poorly demarcated nodules (several mm to
10cm)
◦ Swollen nipples +/- exudate
◦ Ropy lymphatics
does mammary neoplasia metastasize usually
High rates of metastasis
◦ Malignant adenocarcinoma
◦ Occurs in 50-90% of cases
diagnosis of mammary neoplasia
◦ Tumor histology (FNA, biopsy)
treatment of mammary neoplasia
◦ Surgery
◦ Chemotherapy
◦ Radiation
◦ Important to do metastasis check
clinical signs of cystic endometrial hyperplasia/pyometra
◦ Not cycling
◦ Depression, lethargy
◦ PU/PD
◦ Distended abdomen, vomiting
◦ +/- vaginal discharge
diagnosis and treatment of cystic endometrial hyperplasia/pyometra
very similar to in bitches
treatment of ovarian cysts
◦ Luteinization with hCG (induce ovulation)
◦ Surgical drainage
◦ OHE
diagnosis of ovarian cysts
◦ Ultrasound
what is true persistent estrus hard to distinguish from
True persistent estrus – like those caused by ovarian cysts – can be hard to distinguish from a normal cat
(overlapping follicular growth)
what happens if cyst cells are secreting estrogen
◦ Persistent estrus
◦ Or can have no clinical signs (no estrogen secretion)
how can infertility in queens be categorized
◦ Persistent anestrus
◦ Persistent estrus
◦ Cycling queens that refuse copulation with the male
◦ Cycling queens that fail to conceive after copulation with a fertile male; 1st step is to determine if they ovulated
causes of EED/abortion in cats (8)
- FIP
- Feline Herpes Virus
- FeLV
- Panleukopenia
- Toxoplasma
- Salmonella
- Chlamydophila
- Mycoplasma
what should we consider management wise in differentials
◦ Season? Photoperiod?
◦ Recent change in environment
◦ Partner discrimination
◦ Husbandry – vaccine status, deworming, etc.
