Small animal reproduction Flashcards
What is the definition of a bitch?
a female dog older than 6 months
What is an intact male called?
stud dog/dog
What is the definition of reduced fertility?
ability to reproduce but at a rate below that considered regular for that species
What is the definition for fertility
ability to reproduce in a regular manner characteristic of species
what is infertility
temporary inability to reproduce
what is sterility?
complete and permanent inability to reproduce
NOT treatable
What is puberty?
age at which repro organs become functional and reproduction could occur
What is superfetation?
fetuses of different ages
must have preg animal that comes into estrus and subsequently bred/conceives
queen, not reported in dog
What is superfecundation?
fetuses sired by more than 1 male, conceived in one estrus period
common in bitch
When is puberty indicated in dog and cat?
first estrus period
When do small breed dogs start puberty?
6-10 months
When do large breed dogs start puberty
18-24 months
What is the most common sign of estrus in dogs?
‘spotting’/bleeding
What can affect the occurance of puberty or the apparent occurance?
- breed
- silent heat, split heat that is potentially fertile but not noted
- coat length–hides bleeding
- presence of male–first estrus more apparent or actually hasten it
- housed together synchrony–intact females, may reach puberty slightly earlier
- free roaming vs kenneled–free roaming more sexual stimulation if body condition good can enter puberty sooner
What is the characteristics of the estrous cycle in the bitch
monoestrus
nonseasonal except besenji
interestrous interval average 7-8 months
What is the variation of the interestrus interval?
average 7-8 months
4-5 month min
12 months max
Is the interestrous interval affected by the birth of a litter of puppies?
no
is interestrous interval usually consistent/constant within a dog?
yes (relatively consistent)
When do dogs show an estrus potentially?
throughout year
more dogs tend to have in late winter/early spring
conception rates may be higher in spring
What are the 4 stages of dog estrous cycle?
proestrus, estrus, metestrus (diestrus), anestrus
What is the luteal phase in canine called?
metestrus/diestrus
When does the animal exhibit estrus behavior (canine)
bridges proestrus and estrus
What is proestrus in the canine (features)
follicular phase when follicles are growing and producing estradiol
edema
hemorrhagic vaginal discharge
behavior
What is the duration of proestrus in canine?
average 7-10 days
range 4-25 days
What is the pattern of estradiol in proestrus?
rises rapidly then falls near estrus
What are the features of canine estrus?
both follicular and luteal phase
edema of vulva–>flaccid, swollen
less hemorrhage
(follicles start to lutealize even before ovulation!!!)
behavior–receptive to nonreceptive and estrus concludes
What is the duration of canine estrus?
3-10 days (range 2-15)
What are the features of the canine luteal phase?
normal sized vulva
discharge mucoid to dark brown colour, then stops
What is the duration of the luteal phase in the non pregnant vs pregnant dog?
in nonpregnant dog tends to be longer 70-80 days, in pregnant dog it is shorter
Is there much difference between pregnant and nonpregant dogs in the luteal phase?
no
What are the similarities in hormone profiles between preg and pseudopreg animals?
the LH surge basically the same
progesterone levels similar (higher mid diestrus in pseudopreg animal?)
What is anestrus?
period of quiescence between end of diestrus and onset of next proestrus
vulva shrinks in size
What is the duration of anestrus?
4-5 months
Are female dogs receptive during anestrus?
no but they may be submissive to a male
What is the difference in ovulation between younger and older dogs?
younger dogs may ovulate earlier but really it may just be that older experienced dogs show estrus earlier than younger dogs so seems as though younger dogs ovulate sooner
What is important in most accurately predicting ovulation
by knowing the timing of the ovulation
What is occuring endocrinologically during anestrus?
some FSH, LH activity, estrogen activity, progesterone levels baseline. different than other species in anestrus
When does uterine involution occur in non-preg vs preg animals?
non-preg: 110-130d after proestrus
preg 90 days post partum
what is often overlooked in breeding management in the dog?
domestic dogs don’t pair for life, may not be mutually attracted and therefore some management necessary!!
What should you do with pups to encourage good breeding dogs?
allow socializaiton and stimulate sexual desire–mounting non-estrus bitches or other males
What is the ideal first mating for a young male?
a mature female which is receptve
What might cause psychological impotence
constant restraint
What are the important steps of natural mating in dogs?
- female must be in STANDING HEAT
- period of socializing–sniff, play
- mount/dismount
- intromission and vestibular muscle contract
- 3 fractions are ejaculated
- stepping over
What is the first stage of coitus
hop on
thrusting
What happens when the male is fully erect?
they are “tied”
usually occurs after visible thrusting
When does ejaculation occur?
after animals are “tied”
What occurs with stepping over?
the male dismounts but still tied together
what are the fractions of canine ejaculate?
- 1st fraction preseminal fluid
- fraction sperm rich (usually tied by this time)
- prostatic fluid
What are the amounts of the fractions of canine ejaculate?
- 0.5-2mL
- 0.5-3.5mL
3rd 3-20mL
What is the purpose of the 3rd fraction?
sperm transport. important in natural mating, not usually included in AI because sperm deposited into uterus?
What is the most common problem for issues when trying for natural mating in dogs
timing
HOw can you determine ovulation
- vaginal cytology
2. LH determination
why should breeding happen after ovulation in dogs?
becuase the oocyte takes a couple days to mature
What is the key event during canine estrus???? *imp
LH surge!!!!
When is the optimum time to breed in natural mating dogs?
4-5 days post LH
2-3 days post ovulation
When does ovulation occur relative to LH surge?
48 hrs (2 days)
What are the uses of vaginal cytology?
can determine
- when to breed or send bitch to stud
- when fertile period is over–ovulation has happened, estrus is ending
- whelping date
- when to begin termination of preg protocol
- anovulation–female in estrus that fails to ovulate, split estrus
Is usually just one vaginal cytology done?
no, usually serial
How is pregnancy terminated with PGF2alpha?
prostaglandin 2 alpha IM and bromocriptine PO twice daily from days 6-10 of diestrus. good protocol but need to know what day of diestrus in
What is vaginal cytology not good for?
- diagnosis of open pyometra, emtritis or endometritis
2. optimum time for insemination using a single dose of semen–need to be more precise than that
What are we looking at when looking at vaginal smears?
1. mostly epithelial cells--morphology--percentage of cell types superficial cell index karyopyknotic index 2. RBC--# 3. WBC 4. debris
What happens during follicular phase to the vaginal epithelium?
rising estradiol 17Beta proestrus levels stimulate growth of vaginal epithelium
vaginal epithelum reaches a thickness of 20-30 cells and most superficial cells are shed into the lumen. morphology of those cells changes over time
What are we looking for on vaginal smear?
The amount and morphology of epithelial cells
RBC
WBC
debris
What are the types of epithelial cells?
- basal cells
- parabasal cells
- intermediate cells (small, large)
- superficial cells (cornified)
Are basal cells usually exfoliated?
no
Do we want to scrape vaginal wall with canine vaginal cytology?
no, want cells that are already exfoliated
What are the predominant cels in diestrus and anestrus?
basal cells, not usually exfoliated
What are metestrum cells?
intermediate cells with phaoytosed WBCs within it
What are foam cells
intermediate cells with cytoplasmic vacuoles (phagocytosis)
How can you assess vaginal crenulation?
through vaginoscopy
when does vaginal crenulation occur?
in estrus, following edema
What are the methods for making a vaginal smear?
- pipette or dropper
- microscope slide (not very accurate)
- cotton swab
- cotton swab with speculum as guard
What is the pipette or dropper colleciton method
need saline to obtain cells
expel fluid onto slide
spread out cells
dry and stain
Why is the pipette or dropper collection method diffiuclt?
difficult to get instrument in becuase have to get over ischial arch into the vagina and vestibule + the vagina is usually quite long and trying to get to posterior
What is the microscope slide collection method?
cells from vestibule
NOt scraping
stay away from mucocutaneous junction
cells transferred to 2nd slide
What are the problems with microscope slide collectio method?
- cells tend to be representative of vulva, not vagina
2. vaginal cells must exfoliate and travel to vulva–less accuracy–more representative of a few days ago,
What is the cotton swab method?
- moisten swab
- pass along dorsal wall of vagina
- roll swab on microscope slide
What is the issue of using a cotton swab without a guard?
can pick up other cells–vestibular
can be traumatic
must avoid clitoral fossa–many keratinized cells
What is the method of using a cotton swab with speculum?
- moisten swab
- introduce speculum (otoscope tip)
- introduce swab–touch wall of vagina, do not scrape
- role on to microscope slide
What are the advantages of using the cotton swab with speculum method?
- better quality smear
- only exfoliating cells from the posterior vagina are collected
- vagina is more sensitive to hormone changes than the vestibule
What do you stain vaginal cytology with?
- sedi stain
2. modified wrights-giemsa (diff quick)
How do you view the vaginal cytology under microscope?
250x is ideal
can use 100x
bright field
(40x all cells appear cornified–breed too early, power too high–1000x then hard to develop overall picture)
What is the appearance of parabasal cells?
- large vesicular nucleus
- dark staining cytoplasm
- rarely seen unless scrape wall unintentially
What is the appearance of intermediate cells?
- large and small types (larger than parabasal)
- vesicular nuclei
- round (some may be polygonal)
What is the appearance of a superficial cell?
nucleated, polygonal
as matures further then the nucleus becomes pyknotic and eventually loses the nucleus (anuclear, squame)
What is the superficial cell index?
the number of cells from superficial epithelial layers (anuclear, pyknotic, nucleated)/total number of epithelial cells (100 cells)
What are two indexes that can be calculated from the vaginal cytology?
- superfical cell index
2. karyopyknotic cell index
How do you calculate karyoppyknotic cell index?
number of anuclear cells or pyknotic nuclei/total SUPERFICIAL CELLS (not total cells)
What are the ranges of SCI, KPI in early proestrus?
SCI-25-30%
KPI-10%
What are the ranges of SCI, KPI in late proestrus/early estrus?
SCI-100%
KPI 80-90%
What is the optimum time to breed according to KPI?
> =85%
What is the appearance of vaginal cytology in anestrus
few or no cells
no pyknotic or anuclear superficial cells
as animals start to come into early proestrus, what is seen on vaginal cytology
more cells
more intermediate cells
more RBCs (occasional)
occasional WBC
What is the appearance of vaginal cytology as proestrus progresses?
clearance of debris (mucus?)
clearance of RBC (max in early proestrus and as estrus gets closer then bleeding diminishes)
What is the definition of transition from estrus to diestrus cytologically
the onset of diestrus is indicated by 1st day that there is a substancial decline in the number of superficial cells (>20% in SCI)
What is the recommendation for breeding with regards to vaginal smears?
- serial evaluation of vaginal smears
What is an issue with serial evaluation of vaginal smears?
unable to prospectively predict time of receptivity to mating, time of LH surge or ovulation
MORE OF A RETROSPECTIVE TOOL
What is the key event to determine when ovulation will occur?
LH
How can LH be measured?
RIA or ELISA
How do you sample for LH measurement?
daily sampling mid proestrus (may miss occasional dog with short surge)
Is LH measurement cheap or expensive?
expensive
When progesterone is
baseline
LH surge is considered when with respect to progesterone?
when progesterone higher than 1.5 to 2
When does ovulation occur with respect to progesterone levels?
when greater than 2 assume will ovulate, when greater than 4 assume has ovulated
When progesterone is 10-15ng/ml what is occuring? Why is this important?
max oocyte maturation
ideal time to breed
HOw can progesterone be measured?
ELISA-semi-quantitative
RIA
Why might breeders prefer to submit progesterone to a lab?
b/c get a more accurate number
The first significant rise in P4 above 2ng/mL = what?
LH surger
WHen does ovulation occur with regard to P4 levels?
4-10ng/mL
When should breeding occur with regards to P4?
10-15ng/mL
When does sampling of P3 occur?
ever 48hr 5-7 days after proestrus bleeding
White might you use retrospective vaginal cytology?
- did breeding occur at correct time
- determine whelping date
- may be useful for subsequent estrus periods (split heats or false heats)
What is the approach to the problem breeder with regard to history?
- vaccine status
- medications–estrus suppression treatment–can have long lasting effects
- repro history (litters, method, litter size etc), fertility of siblings, male involved?
How is the uterus examined?
palpate through abdomen
U/S including ovaries
What is the vulva examined for?
- conformation
2. infolding
What is the vagina examined for?
- abnormal discharge
2. adequate size
What are commensal bacteria of the vagina?
- e. coli
- staph
- strep
- proteus mirabilis
- pseudomonas aeruginosa
Why are uterine cultures not usually done in the dog?
very hard to access
transcervical not really possible
laparotomy invasive
What is the one pathogen that if you culture from the vagina of the dog is considered always pathologic?
brucella canis
Is mycoplasma/ureaplasma an important result from a vaginal culture?
probable significance overgrown
What can you use vaginal endoscopy for?
evaluate vaginal epithelium for inflam, discharge
evaluate crenulation
anestrus-pink, dry looking
proestrus–edematous, paler
estrus–crenulation as edema starts to “dry up”
but not commonly done
