Canine/Feline Therio - 1 Intro Flashcards
In the majority of domestic species, the interval between one ovulation and another is approx
21 days
Oestrous is the period of sexual receptiveness when
Mating is allowed
Luteal phase consist of metoestrus and dioestrus is the period of
Preparation of pregnacy
Pro-oestrus is the period of preparation for return to
Oestrus
Anestrus is the period of
Sexual inactivity
The average length of one ovulation and the next in a bitch is
7 months
The average length of one ovulation to the next in the queen is
14-21 days
The breeding pattern of bitches are
Non seasonal mono oestrus
The 1st (pubertal) oestrus onset in the bitch occurs when
Approx 9mths ( 6-14mths)
Peak fertility in the bitch is reached at
2yrs (until 6-7)
The average interval of cyclicity of the bitch is 7mths but divided into different stages, name these stages and the associated length of time of completion
Pro-oestrus: 10days
Oestrus: 10days
Luteal Phase (Metoestrus/dioestrus: 2mths (pregnancy or non pregnacy)
Anestrus: 4.5mths
What are the clinical signs of pro-oestrus in the bitch (7 points)
Stimulation of follicle development by FSH and LH
Enlargement and reddening of vulval lips
Appearance of serosanguineous vulvar discharge
Increased attractiveness to male dogs
Increased urine marking and tendency to roam
Sexual attractiveness but refusal to allow mating
Vaginal mucosa changes from cuboidal epithelium to a startified sqamous epithelium
What are the clinical signs of the oestrus in the bitch (6 points)
Inviting receptive behaviour
Standing to be mated
Movement of tail to uncover the vulva & Spinal lordosis
Pheromones are secreted under the influence of oestrogen within RT discharge and urine
Loss of oedema, wrinkling of vaginal wall mucosa.
Characterised initially by elevated conc. of oestrogen, which then decline prior to ovulation
Ovulation in the bitch is stimulated by
LH surge
LH surge stimulating ovulation in the bitch occurs when
Few days after peak concentration of oestrogen
Ovulation is spontaneous in the bitch and occurs how long after the surge in LH
48-60hrs after
In the bitch prior to ovulation, there is an increase in a critical factor hormone called
Plasma progesterone
Fertilization period in the bitch is the time
When oocytes are available to be fertilized
In the bitch, the fertilization period commenses
2 days after ovulation
How long does the fertilization period in the bitch extends after its commensal
Extends until 5 days
Fertile period in the bitch is the time
During which mating could result in conception
At the time of ovulation in the bitch, oocytes are immature and can not be fertilized immediately.
Fertilization can only occur when?
Extrusion of the 1st polar body and completion of the 1st meiotic division to form the secondary oocyte
In bitches, maturation of an immature oocyte to a secondary oocyte takes how long? Where does it occur? and how long does it remain viable?
48-60hrs within the distal oviduct (start of fertilization period) and remains fertilizable for 9-10days
In the luteal phase in bitches, progesterone continue to increase to reach what conc. by the end of oestrus
10-25ng/ml
In the bitch luteal phase, what are the luteotrophic factors
Prolactin, LH and to some extent progesterone
In the bitch, name some prolactin inhibitors
Cabergoline and Bromocriptine
Prolactin inhibitors and prostaglandins will do what in pregnant and non-pregnant dogs
Terminate the luteal phase after day 25
In the bitch, anestrus is the period of sexual inactivity and marks the interval between
Dioestrus and the start of the next oestrus cycle
What are the signs of anestrus in the bitch (6 points)
Throughout anoestrus the reproductive tract is quiescent.
Internal and external genitalia including mammary glands are at their smallest observed size.
Vaginal wall is relatively thin and easily traumatized by digital examination/collection of epi cells
Endometrial repair occurs in bitch that has whelped
Not lengthened by pregnancy or lactation
The bitch has no attraction to or from the male
What is the progesterone profile during pregnacy in bitches
Progesterone conc. are slightly higher in pregnant bitches
Progesterone plateau is broader during pregnancy
Luteal phase is slightly longer in non pregnancy (66 days) compared to pregnancy (63 days)
What is the difference in the prolactin conc. between preg and non preg bitches
4 times greater in pregnant bitches
What happens to the progesterone conc. during the 2nd half of the luteal phase in the bitch during pregnancy
It starts to decline
What happens, in the bitch when there is a decline in progesterone conc. in the 2nd half of the luteal phase during pregnancy
Concomitant increase in plasma prolactin concentration (starts increasing at day 30, plateau at day 50 and remains elevated throughout lactation)
The decline in progesterone during pregnancy triggers what?
Parturition
During lactation in bitches, action of suckling induces what
Increase secretion of prolactin
Lactation in the bitch lasts for how long? what happens to prolactin conc?
6wks
Prolactin conc declines
What is psuedopregnancy in bitches
The long luteal phase of the non-pregnant cycle
The clinical signs of psuedopregnancy is mediated by what hormone
Prolactin
Clinical signs of psuedopregnancy in the bitch includes
Anorexia, nervousness, aggression
Nest making
Nursing of inanimate objects
Lactation and occasionally false parturition
How is puedopregnancy in the bitch treated
Admin. of prolactin inhibitors (cabergoline/ bromocriptine @ 5ug/kg ; 0.1ml/kg orally) for 5-7days
What is the breeding pattern of cats
Seasonal polyestrus
The oestrus cycles of queens are dependent on what
Photoperiod
The how long are the photoperiods in cats?
12-14hrs (long day breeder)
If bitches are spontaneous ovulators, what types are queens?
Induced
Age what age do queens reach maturity?
6 to 9mths
Peak fertility in queens is reached when
2-6yrs
Onset of proestrus and estrus in cats are indicated by what?
Behavioural signs
What happens to queen’s cyclicity exposed to less than 8hrs of light
Cyclicity stops abruptly and folliculogenesis is inhibited
The cyclicity of queens affected by decreased light can be resumed when
Exposed to 14hr photoperiod after 16days
What are the stages of the estrous cycle in the feline and the associated lengths of each cycle
Proestrus: 0-1day Oestrus: 2-6days Interestrus 8-15days Diestrus or psuedopregnancy Anoestrus: occurs naturally in periods of short daylight hours with increase secretion of melatonin
Proestrus in queens are characterized by (6points)
Rubbing Threading with rear feet Vocalisation Reduced aggression to males Lasts 1 to 2 days Estrogen is predominant
Estrus in queens are characterized by (9 points)
Increased vocalisation
Lordosis
Allows copulation
Lasts 5 to 8 days
Duration not influenced by copulation
An ovulatory cycles occur every 2 to 3 weeks
Interestrous period of a few days may occur
Queen screams at end of copulation and is aggressive to tom
Repeated breedings are common after this
Interestrus is the period
Between successive estrus if ovulation does not occur
In pregnant queens, CL secrete what hormone and for how long
Progesterone for up to 65 days
In non pregnant queens, CLs persist for how long
30-40days
Lactating queens do not resume cycling until how long after weaning
2-3wks
Differences between canine estrous cycle and other species
Long interestrous interval
Long proestrus and estrus
Lifespan of CL is independent of pregnancy
Oocyte ovulated is immature
Long viability of oocyte and sperm within the uterus
