Basic feline reproduction Flashcards
The queen reaches puberty at
4-12 months of age influenced by
- breed
- body condition 2 kg minimum typically (average bodyweight at puberty 80% of adults)
- time of year when they were born (summer/ autumn-born cycle earlier than spring-born)
- social environment
Feline Peak fertility at
- 2-8 years
- Reduced fertility after 10 years
- Fertile queens over 20 years are reported
Estrus cycle of the queen. 328
seasonal long day breeder with anestrus
being observed over 3-4 months when the day length is short.
proestrus 1-2 days
estrus 4-10 (avg 7) days
post-estrus/inter-estrus 8-10 days
diestrus (when pseudo-pregnant) 40 days
diestrus (when pregnant) 60 days
anestrus 30-90 days (variable)
Non pregnant luteal phase (pseudopregnant): lasts 30-45 days
Pregnant luteal phase: 62-64 days
Tomcat puberty ?
slides unavailable :(
Average interval from one ovulation to the next in queens
14-21 days (can be shorter in oriental breeds)
(Most cats 2 weeks)
Signs of estrus in queens.
Proestrus can’t always be detected:
❖ More affectionate, rub against other cats and humans
❖ Slight swelling/reddening of the vulva lips, no vulva discharge
Estrus:
❖ the queen becomes more active, vocalizing, spinal lordosis, tail turned to one side, occasionally reduced appetite and urine spraying in queens, passive to the male
Affect of Daylight on anestrus: (5)
❖ Absence of cyclicity in periods of short
daylight with increased secretion of melatonin and elevated prolactin.
❖ Anestrus Between October and january in northern hemisphere
❖ Shorthaired cats more commonly
continue to cycle over winter
❖ 10 hours of daylight → enters anestrus
❖ 14 hours of daylight → good levels of
fertility
Lactation affect on anestrus: (3)
- Many queens do not cycle during lactation
- Many return to cyclicity after 2-4 weeks (in breeding season)
- The rest in 2-8 weeks after weaning
Silent heat in queens.
Normal estrus cycles and follicular waves WITHOUT showing signs of estrus.
Can occur:
- If the queen is nervous dispositioned
- If she is in the low end of the social scale
- If she is inexperienced
- If she is distracted
- If she has a male preference
Diagnose with vaginal smears, bloods for estradiol, and serum P4 to check if ovulation has occurred.
Normal Intromission signs in cats: (4)
❖ Vocalization
❖ She will strike at the tom and he will bite her neck
❖ Afterwards excessive licking of the perineal area and the queen will roll
❖ Short break followed by multiple further matings (important to induce ovulation)
If the queen has not ovulated:
- Follicles will grow at the time of elevated estrogens
- Towards the end of estrus (day 5-6) the follicles will become atretic, estrogen
levels will decline and estrus behavior wanes → the queen returns to
inter estrus.
Feline Ovulation
Induced ovulation →
mechanical stimulation of the vagina → neuronal triggering in the hypothalamus → release of GNRH →
LH surge (after 2-4 hours)
Ovulation can be induced also by grooming/ self-grooming or artificially with a cotton swab.
Spontaneous ovulation occurs in older queens and queens in presence of a tom
cat – pheromonal/visual stimulation.
Ovulation is related to:
❖ The day upon which they are mated
❖ The quality of matings
❖ The interval and number of matings – approximately 50% ovulate after a single
mating, the optimal stimulation is four matings within 2-4 hours.
Fertilization in queens. (4)
Oocytes are immediately fertilizable when ovulated after extrusion of the polar body as secondary oocytes.
Estrogen levels will decline rapidly at the same time as the progesterone rises.
The queen will go out of estrus in 24-48 hours.
The oocyte are fertilized in the ampulla of the oviduct→ reach the uterus in 3-
4 days post-ovulation.
Constant or prolonged estrus. (5)
“nymphomania”, hyperestrogenism
- In some queens the follicle waves follow one another so closely that there
is no gap between the observed estrus behaviour. - The queen will show estrus behavior and will be interested in mating.
- Often this is very inconvenient for the breeder → induction of ovulation (mechanical or with hCG).
Cystic follicles and ovarian tumors can also cause prolonged estrus.
Luteal phase in queens.
Rapid end to estrus after ovulation → the luteal phase is almost synchronous
with the end of estrus.
Progesterone increase rapidly and is solely produced by the CL.
Progesterone profiles and concentrations do not differ between pregnant and pseudopregnant queens in the early luteal phase.
Pseudopregnancy in cats happens when
the queen ovulates but doesn’t get pregnant.
But the luteal phase is somewhat shorter than the truly pregnant cat’s.
Length of gestation in queens is
variable both within and between individuals.
❖ On average 62-65 days
❖ Gestation length is not related to age, parity, number of kittens, genetic.
❖ Up to 10% of all cats may show behavioral estrus during pregnancy (commonly between D20-D40).
❖ In cats, we often see superfecundity = mating with several tomcats.
Maintenance of pregnancy in the queen.
(5)
❖ A lot is still unknown
❖ Most - maybe all P4 is produced by the CL BUT
❖ Because late ovariectomy does not always result in abortion → either placenta
produces P4 or P4 is not required for maintenance of pregnancy from day 40/45.
❖ Baseline levels of 1-2 ng/ml are not essential for onset of delivery like in the bitch.
❖ The queen does not show a fall in rectal temperature shortly before term as is seen for the bitch.
Prolactin in queens. (3)
❖ Is the main luteotropic agent
❖ Starts to increase from day 30 after ovulation, reaches a plateau from
D50 to parturition and increases again at parturition.
❖ Prolactin inhibitor (Galastop®) causes cessation of progesterone secretion and maybe termination of pregnancy - unclear in cats.
Relaxin in queens. (4)
❖ Similar profiles as in the bitch
❖ The only pregnant specific hormone during pregnancy
❖ Secreted by the placenta
❖ Increases from about D25
Action: act directly on the CL, may stimulate prolactin secretion from the pituitary gland.
Parturition in the queen. (3)
During The last week of pregnancy:
❖ Nesting and mammary development
No remarkable changes in rectal temperature as seen for the bitch.
❖ On the day of parturition the progesterone normally declines to about 2ng/ml.
Parturition phases in the queens.
- phase, 6-12 hours (36)
❖ The queen may become restless, go into her nest, lick her vulva and pant.
2.phase, 2-3 hours
❖ Begins with straining in lateral/ventral recumbency or in defecating position.
❖ The kittens are expulsed about 5-40 minutes apart depending on the presentation.
❖ Complete parturition is normally achieved within 2-3 hours.
❖ Posterior and anterior presentations are normal in the cat.
3.phase
❖ The fetal membranes are expulsed with each fetus or shortly after.
❖ The last fetal membrane is usually expelled not more than 15 min after the last fetus is born.
Length of each phase of parturition in the queen.
- phase, 6-12 hours (36 max)
2.phase, 2-3 hours (usually)
3.phase, essentially simultaneous with phase 2
Feline dystocia. (5)
Between 1%-18% incidence depending on the breed.
A higher risk is seen in pedigree litters than in mixed breeding.
A higher risk in dolichocephalic and brachycephalic types than in mesocephalic
types.
Maternal causes (particularly uterine inertia) are much more common than
fetal causes (fetomaternal disproportion and faulty disposition).
Uterine torsions are rare but described close to term in association with illness.
The management of obstetric cases are similar as for the bitch.
