Breeding Management - General Flashcards
what are 4 reasons you might perform a BSE on a mare
1) infertility
2) pre-purchase exam
3) identified pathology
4) routine postpartum
when is the best time to perform BSE on the mare
in estrus - easier to access the uterus through the cervix
what are the components of the BSE for the mare
1) history
2) general inspection
3) general PE
4) palpation per rectum
5) vaginal exam
6) ultrasonography
7) endometrial biopsy
8) endometrial culture and cytology
what are 7 factors from the history that are important for the BSE of the mare
1) time of year (horses are seasonally anestrus)
2) parity
3) age
4) number of breeding attempts so far
5) any problems in previous parturition
6) is she cycling regularly
7) previous treatments this year
what 5 things do we look for when doing a general inspection as part of a BSE
1) external conformation
2) vulvar discharge
3) body condition
4) lameness
5) peritoneal conformation
what is the most significant factor causing subfertility in mares and why
poor perineal conformation; will often have infection from fecal or air contamination
what are the 3 barriers to contamination of the uterus
1) vulvar seal
2) vestibulovaginal sphincter
3) cervix
what angle of vulva do we want to see in a normal horse
vertical; <10 degree forward angulation
what is a normal amount of vulva in relation to the pelvic floor in horses
less than 1/3 above the pelvic floor
what is a normal amount of perineal body in the horse
3-4cm between the anus and dorsal commissure of vulva
what forms the vestibulovaginal sphincter
1) caudal vagina
2) hymen
3) internal floor of pelvis
4) constrictor vestibuli muscles
you perform the air test and hear an inrushing of air, what does this indicate
the vestibulovaginal sphincter is compromised
what is Caslick’s surgery
suturing the dorsal aspect of the vulva to form a tough membrane resistant to infection
what may cause variation in findings on transrectal palpation (3)
1) stage of cycle
2) abnormalities
3) species
when you perform a rectal palpation, what is the first thing you want to determine
is she pregnant???
you perform a rectal palpation and determine that the animal is not pregnant; what is the next step?
is she cycling? (is there a CL)
in cows, what structures can you feel? how does this compare to the mare
follicles and CL; only follicles and the OV fossa
what can ultrasound be used for
1) pregnancy diagnosis
2) stage cycle
3) abnormalities
when visualizing the vagina and cervix on vaginal exam, what 3 things should you be looking for/keep in mind
1) anatomy
2) pathology/discharge
3) stage cycle
what is the best way to diagnose tears and adhesions of the cervix
digital exam
in diestrus, how does the cervix appear
central/tight, pale, dry
in estrus, how does the cervix appear
on floor/relaxed, pink-red, moist
what is the purpose of endometrial culture and cytology
determine if the uterus is free of inflammation and infection
what are the 4 indications for endometrial culture and cytology
1) as part of the complete BSE
2) infertility/irregular cycles
3) you saw abnormalities on US
4) vaginal discharge
it is common to use the cap of the swab for ___________ and submit the swab itself for __________
cytology; culture
what is an important consideration for endometrial cytology/culture
strict sterile technique
what is considered abnormal endometrial cytology of the mare? what about the cow?
> 3 neutrophils per high power field; > 5-10% neutrophils
how do we interpret the 3 results of cytology:
1) swab POS + cytology NEG
2) swab POS + cytology POS
3) swab NEG + cytology POS
1) likely contamination
2) endometritis
3) likely endometritis
what can be used to identify cows with subclinical endometritis
Metricheck
what component of the BSE correlates to the likelihood of a mare carrying a foal to term
endometrial biopsy
what are the two indications for endometrial biopsy in the mare
1) prepurchase exam of broodmare
2) to determine cause of infertility
T/F there are no pain receptors in the non-pregnant endometrium
T
where is an endometrial biopsy taken from
horn base
biopsies are closely associated with _______ rate
foaling
when are additional tests of the BSE done
when specifically indicated
why might you want to manipulate the cycle of mares or ewes
to allow out of season breeding
what are 4 disadvantages of breeding programs
1) stress to animals
2) cost of drugs and labour
3) expressed estrus may be weak, low intensity in some programs
4) not all animals respond
what are some reasons why an animal might not respond to a breeding program
1) BCS
2) management
3) nutrition
4) genetics
T/F you can control the estrous cycle by targeting the follicular phase, the luteal phase, or both phases
T
what are 4 MANAGEMENT TECHNIQUES for estrous cycle control
1) manipulate daylength
2) male effect
3) increase plane of nutrition
4) short term weaning
what is a geographical factor that influences short-day breeders
latitude
what is the effect of melatonin on mares? on ewes?
mares: increased melatonin INHIBITS GnRH release
ewe: increased melatonin STIMULATES GnRH release
how do we fool mares into thinking it is spring? (so she foals early in the year)
expose her to artificially long days starting in the fall
how do we fool ruminants into thinking it is fall?
expose them to increasing darkness starting in the late summer
what is the most powerful stimulus of estrus that is widely known and used
male effect
what is the hormonal effect of male exposure
stimulates the release of GnRH and LH
sight, smell and suckling of a calf (increases/decreases) LH release; what is this called
inhibits; lactational anestrus
short-term weaning is best when combined with or
increasing plane of nutrition; male effect
how long should you wean calves for to induce estrus at the beginning of the breeding season
24h
what is the term to describe increasing the level of pre-breeding nutrition
flushing
flushing works best in what body condition
thinner
when should flushing start
2-3 weeks before start of breeding season
what hormone can we give to induce luteolysis
PGF2α
what are limitations of PGF2α as a treatment for controlling the cycle
only works in animals with a CL; will not work in anestrus animals; will not synchronize ovulation; side effects
PGF2α will lyse the CL and come into estrus in ________ days
2-5
how does giving exogenous progesterone or synthetic progestagens cause ovulation
suppresses LH release during treatment -> LH builds up in pituitary -> surge of LH when progesterone treatment stops -> estrus -> ovulation
what are 5 forms of progesterone
1) intravaginal devices (CIDR; PRID)
2) oral (MGA)
3) daily injection
4) long-lasting injection
5) ear implant (Syncro-Mate B)
what are 6 hormones that can be used to control the follicular phase
1) PMSG (eCG)
2) HCG
3) GnRH
4) estrogens
5) LH
6) FSH
what is unique about giving GnRH in cattle
depending on when it is given, it will either stimulate ovulation or emergence of a new follicular wave
what is an example of exogenous GnRH that is used in mares
deslorelin
how does HCG induce ovulation
acts like LH
how are estrogens used in cattle programs (3)
to induce estrus, ovulation, or emergence of a new follicular wave
what is the function of HCG
induces ovulation
what is the function of exogenous FSH
stimulates follicular growth
what hormone is used for superovulation in embryo transfer programs
FSH
PMSG acts like _____ in horses and ____ in ruminants
LH; FSH
what can PMSG be used for in ruminants (2)
superovulation; out of season breeding in sheep
T/F combination programs are species-specific
T