Equine Reproduction Flashcards

Lectures 1-4

1
Q

Overview

A
  • mares cycle regularly through breeding season (controlled by photoperiod)
  • can manipulate this with their environment in some cases to cycle over the winter - idea is to get the foals born at right time with food available
  • foals should be born in spring/summer optimally
  • Arbitrary artifical birth date depending stimulated by thoroughbreds depending on hemispheres. (Jan 1 in North, Aug 1 in southern) - try to manipulate the mares forward to get them closer to their actual birth date
  • age type racing and sales: if you have a foal that was born in August it is going to look better for sales when it is a yearling than if it was born in July
  • for thoroughbreds –> get as close to beginning of season as possible
  • Sports horses: depends on how it fits into that schedule and management
  • conception rates will be lower at a younger age
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2
Q

Mare Reproductive Anatomy

A
  • 3 gateways to the mares tract: perineum, transverse fold (end of the vestibule)- the vaginal vault and then the cervix
  • 3 layers of protection
  • means there are 3 stops for bugs
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3
Q

Mare Anatomy

(Ovary)

A
  • mares ovaries are quite responsive to the season
  • will be rather small if there is no activity (walnut) - anoestrus in the winter
  • picture: small anoestal ovary and then larger developing ovary with follicles - follicles get stimulated to be active (often feel like a bunch of grapes when actively ovulating)
  • All mares will be ovulating through an ovarian fossa - this is important!! - rather than rupturing in various places, it is always going to rupture in the same place - important in gamete harvesting as well
  • Follicles: you will be able to be able to feel the little bubbles
  • After ovulation: CL formed and then in horses a corpus hemorrhagica is formed
  • all held together by suspensory ligaments that vary on length depending on the mare!
    Maiden mares that have never had the pull of pregnancy - shorter and ovaries sit just ahead of tuber coxae
  • mares with lots of babies - quite a lot of stretch, ovaries can be anywhere from midline to quite low (quite a bit of variability)
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4
Q

Mare Anatomy

(Uterus)

A
  • long horns and a reasonsably short body
  • T or Y: important for the implantation of the embryo and harbor for disease
  • endometrium is important for implantation of the embryo as well as the placenta, it is also another potential site for disease!
  • broad ligament can be a spot for hemorrhage during foaling difficulties - important to identify
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5
Q

Mare Anatomy

(Cervix)

A
  • mares: about 10cm
  • in ponies it is about 4cm
  • has a definitive os cervix
  • anoestral cervix has tone to it, but no color (closed opening)
  • oestral cervix: rosebud appearance and becomes a wilted rosebud appearance as it gets closer to ovulation (melting into floor of vagina) - good way to judge if the mare is in season
  • needs to be soft to be receptive to the stallion!
  • Dioestral: after ovulation, more tone to it and then under the influence of the pregnancy it is a tight fist
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6
Q

Mare Anatomy:

Perineum

A
  • First stop to prevent infection
  • also one of the first spots for veterinarian intervention
  • clitoris is where you get a lot of harboring of disease
  • need to look at these areas for pre-breeding swabs
  • remember clitoral sinus and clitoral fossa
  • remember this orientation and with multiparous mares this becomes altered and then you run into issues with infections and such
  • not a nice straight confomation
  • h= bladder
  • there is space in the abdomen which makes sense so if you have a big foal developing it will drop down and not squish the bladder
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7
Q

Breeding Season and Oestrus Cycle

A
  • Throroughbreds: earlier in the year
  • polar ponies: later in the year (when they are finished playing and don’t have to be in sales/racetrack)
  • sports horses: usually in the middle of the year
  • Generally April, May, June is peak time
  • after that- no chance really of getting them pregnant and then once the clocks change there really is no go
  • want to increase day length if we can as it has a lot of effect on their cycle
  • bad weather can really impact the way the mares function! - really want to push the daylength to about 16 hours
  • can do this with artificial light - enough to read a paper
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8
Q

Influences on Breeding Season and Oestrus Cycle

A
  • stimulate the hormones from the brain that we need to move forward
  • green grass effect: if you have grass, that is good for the mares and then there is a response to try and enhance reporduction at that point
  • plane of nutrition increase in empty mares will aid conception rates (like FA’s)
  • daylength is still key!
  • but weight will have an effect!
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9
Q

Hormonal Pathway

A
  • melatonin in the spring time drops and that stimualtes the GnRH release in the hypothalamus (which we can alter sometimes)
  • which then stimulates the anterior pituitary and so on
  • we know that we can stimulate the GnRH release at times and increase daylight
  • nut ovary –> grape structure producing oestrogens
  • get behavior changes and changes in the tract
  • need feedback of oestrogen to promote follicle maturation by the relasse of LH!
  • without LH surge, don’t get anything but smoldering ovaries that are producing enough oestrogen to get changes in behavior but not enough to get proper maturation of the follicle or ovulation
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10
Q
A
  • We need this feedback of estrogen to have that necessary LH surge
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11
Q

Transitional Period

A
  • time just before the peak breeding season after winter
  • this is the part we are trying to move forward in terms of mares cycling for thoroughbreds
  • variable, depends on hemisphere!
  • Want to kick ovaries into action to get early oestrus cycle
  • mares will show signs but they won’t have enough oestrogen to have LH surge
  • We know we can manipulate the light - need to be able to read newspaper in the stable
  • Dopamine anatognist can be applied to fire ovaries out of the transition stage
  • in the US: use progesterone/estradiol to try and prime up the whole HPA axis –> don’y have this in the UK and EU
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12
Q

Oestrus Cycle

A
  • once we are out of the transition phase we are into a true oestrus cycle
  • oestrus ballpark is about 3 weeks
  • really only a few days where they will actually be able to stand
  • There are only a few days when they are ready to stand (then you are talking about AI or naturally breeding)
  • PGF2a release from the uterus kicks off the next cycle
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13
Q

Oestrus Cycle: Hormones

A
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14
Q

Oestrus or Follicular Phase

A
  • follicular development will lead to oestrogen release
  • mares are then starting to show signs they are ready to be mated
  • uterus under the influence of oestrogen will become oedemetous (wet woolen sock) –> like a heavy doughy tube
  • wink, posture and pee
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15
Q
A
  • a bunch of small follicles (1-2 cm in diameter) - all under the influence of FSH
  • then start to get one big decent sized dominant follicles and then shut the rest up
  • occassionaly end up with 2 dominant follicles - but if more than one gerts ovulated off then there is the twin potential
  • If we have more than one dominant follicle, there is potential for twins which is not ideal for horse repro
  • follicle goes towards ovulation fossa and then shoots egg into fallopian tube - will see a “collapse down”
  • will see hypoechoic activity in the middle of the follicle
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16
Q

Oestrus: Follicular Development

A

-want to see an increase to the size of the follicle (why we measure in cm) to where we can possibly manipualte with drugs

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17
Q

Oestrus: Ovulation

A
  • some mares will variably want to ovulate at a 3.6 cm or 5cm follicle which makes it hard to mate with a stallion
  • work with certain mares and know what their size pattern is
  • measuring follicles does help, but is not the sole way we tell oestrus
  • Once an ovulation has occurred (shown as flattenting on other slide) , we have a corpus haemorrhagica (baiscally blood into the space) that forms and then become CL to produce progesterone
  • the presence of a corpus hemorrhagica is a good sign that she has ovulated already
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18
Q

Oestrus: Ovulation Hormones

A
  • follicle release vs. CL and hemorrhagica formation
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19
Q

Oestrus: Uterus

A
  • again “wet woolen sock”

cartwheel appearance on US is what you want to be looking for!

black fluid - oedema –> remember : Oedematous uterus

closer to standing oestrus - you will possibly see some fluid accumulation in the middle (should be less than 2cm!)

If more than 2 cm —> excessive fluid

usually fluid reduces just before ovulation (can look for the decrease)

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20
Q

Dioestrus or Luteal Phase

A
  • usually a window of 24-48 hours before the cervix closes (3-4 days aft
  • they will NOT be having the presence of the stallion anymore
  • we can also manipulate the lysis of the CL –> IMPORTANT
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21
Q

Manipulation of Oestrus Cycle

(transitional phase)

A
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22
Q

Manipulation of Oestrus Cycle

(dioestrus)

A
  • Can give PGF2a to get rid of that CL
  • but the CL must be ripe enough to be lysed by the PGF2a (5 - 7days)
  • When you know you have your corpus hemorrhagica that is day 1
  • in attempts to help bring these mares forward by a week or two
  • 2 types of PGF2a you can give (IM ONLY)
  • this is a powerful hormone - so they need to know what they are doing and know how to give properly
  • people need to be sure they know how to give an IM injection!
  • it can really affect horses and people as well!
  • You will get sick if you accidentally jab yourself with this
  • never to be used if anyone thinks they are pregnant!
  • can also even cause asthma in people by inhalation
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23
Q

Manipulation of Oestrus Cycle

(Dioestrus- Prolonging or support of dioestrus)

A
  • we know now that we can shorten the cycle
  • NOW, how do we lengthen it?
  • oral prgesterone that needs to be given everyday
  • dont pour into feed and mix in with their hands!
  • progesterone can have adverse effects on people as well
  • It IS legal for an FEI (equestrian) horse
  • if you give it to a horse you think is competing though, you need to look back at the regulations
  • Depo provera (not licensed for horses) can only be used with good reasoning
  • Regumate is a better oral and licensed oral preparation to use
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24
Q

Manipulation of Oestrus Cycle

(Inducing Ovulation)- HCG

A
  • mimics LH surge
  • want surge to make follicles mature and ovulate
  • mix up solution and give IM or IV
  • nice water base- and mix it up with solution
  • quite handy
  • not good for older mares as they tend to not respond well and indications that they may get used to it with multiple applications - won’t have desired response
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25
Q

Manipulation of Oestrus Cycle

(Inducing Ovulation)- GnRH agonists

A
  • hopes to promote the stimulation for the ovulation
  • most the time will ovulate in a 48 hour gap
  • we will drive the follicle, but won’t reduce fertility
  • chorulon will ovulate the follicle as long as it is 3cm, but won’t necessarily mature it to the same rate
  • Ovuplant will drive it to mature and ovulate and you are not going to get a reduction in fertility
  • chorulon may be good for frozen semen bc it means you are making the cycle shorter
  • ovuplant for throughbreds so we have bigger window to get them to the stallion and the studs
  • ovuplant is a Subcutaneous implant you put in with a big syringe, so you can’t short cycle them off - if you want to bring them back, won’t respond to PGF2a
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26
Q

Reproductive Abnormalities: Ovary

A
  • Anovulatory follicle can be 6-7cm or even get up to 10 cm
  • see in the shoulder seasons or the prolonged transitional season
  • these are not the same as a follicular or ovarian cyst! it is a follicle that just hasn’t had the surge to push it
  • sometimes called “autumn follicles” as the mares don’t think they need to breed anymore - can be a massive pain!
  • Just a follicle that hasn’t had the urge to push it, will over time eventually rupture
  • they may be painful - be careful when examining
  • The horses may be misbehaving due to improper hormones
  • Granulosa Theca Cell Tumor: not to be confused with your corpus hemorrhagica
  • get honey comb type appearances
  • some of these could get massive before we caught them with scanning (basketball size) - would then need to be SX removed and they would have to be on their back
  • probelm is that they produce inhibin - inhibin is a feedback loop so it will suppress the oestrogen and make them have more stallion like behavior (wont cycle properly and will end up surpessing the other ovary)
  • will end up feeling one that is repressed by the inhibin and one that is not
  • can now measure AM hormone and use US to make Dx
  • not all GTC’s will produce the same amount of hormone across the board
  • can run inhibin to get final Dx
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27
Q

Reproductive Abnormalities: Uterus

(endometritis)

A
  • we know it gets oedematous and is also the touching point for conceptus/fetus and placenta
  • because it is vascular, we end up with bugs there
  • endometritis is a common thing among mares
  • ALL SEMEN IS DIRTY- including chilled or frozen semen
  • will always cause some degree of metritis post breeding and that is part of the repair process
  • as mares get older they lose their immunity in the endometrium - struggle to get more control and can end up with scarring and a resulting persistent metritis
  • when we are breeding, we want to manage the post breeding metritis as we dont want bugs to set up shop in there
  • then we have post-foaling metritis from parturition
  • conformation of the mare is also a part of metritis (change in shape of perineum)
  • the ones we need to be aware of as a vet as it is our responsibility is Contagious endometritis (CEM), Kebsiella, Pseudomonas
  • this can extend our oestrus period as the body is trying to drive it out –> mare may be in season and trying to stand for 10,12, 14 days (rather than normal 5-7) and that is a problem! - not actually in season
  • or if she comes back into cycle too early!
  • Infection is goign to keep that cervix open as it want to clear something out –> will drive her to continue showing oestrogenic signs
  • can have persisitent fungal ones as well! (2 ways of treating these)
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28
Q

Reproductive Abnormalities: Uterus

(post breeding endometritis: Treatment)

A
  • need to get everything out, lavage is the best option
  • (just need to wait 6 hours post ovualtion and service with insemination or covering)
  • Not every mare needs a lavage, but a lot of them it helps
  • want phosphate buffered saline to make sure it is not too corosive as it is a luminal env’t
  • should run a culture and senisitivity with it as well so we can pick the AB
  • The one we use more often is Ceftiofur - cephalosporin (broad spectrum, doesnt seem to harm uterine env’t)
  • can even use vinegar for fungal infection
  • myometrium (muscular layer) - want that to contract to get fluid out –> oxytocin (also allows for milk letdown!)
  • Corticosteroids: something we are starting to use after ovulation to reduce inflammation
  • probably only other systemic drug other than the oxytocin to try and reduce the effects of the metritis
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29
Q

Reproductive Abnormalitites: Uterus

(chronic endometritis/endometriosis)

A
  • can diagnose by biopsy! -can tell you what kind ofpregnancy rates you are going to have
    if we want to look at the actual cells - do a swab
  • sometimes use corrosive agents to try and get the body to shed the endometrium to promote a new healthy layer for the conceptus
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30
Q

Endometriosis- Kenney Scale

A
  • healthy uterus at top and then decreases towards bottom
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31
Q

Reproductive Abnormalities: Uterus

(3)

A
  • things IN the uterus that may be going wrong
  • top right: can tell it is a of dioestrus and those are endometrial cysts–> can easily be confused for pregnancy!
  • or you can have a cyst and pregnancy and confuse for twins
  • cysts will vary slightly over the breeding season but if you get a good measurement, then you can usually catch them (map your size)
  • middle: foreign body in the uterus (uterine marble which we use to stop them from cycling to manipulate pregnancy) - often get left there! –> leave an acoustic shadow (can know if is a FB)
  • can even find broken off swab tips
  • uterine adhesions
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32
Q

Preliminary Considerations for breeding a mare

A
  • what they are going to do and when
  • thoroughbreds breed for a defined birth date
  • depending on function of horse
  • Thoroughbreds are always natural breeding (cover)
  • remind them that they will INDEED need to be prepared to have a foal in 11 months time
  • gestation: 11-12 months
  • polo ponies towards the end of the season - not as worried about embryos and such when they are for sport seasons
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33
Q

Breeding Soundness Exam

A
  • has she had a foal before?
  • have they had pelvic fracture or colic Sx - not a good breeding candidiate! - may be good for donate embryo though?
  • neither is a young filly, baby with a young horse pelvis - if you are trying to breed them, may run into dytocia risk
  • need to check soundness of the horse and that includes orthopedic stuff! - can they actually carry the foal?? (70-80 kg of foal)
  • no point in breeding a mare that is struggling to manage its own body weight
  • could lead to laminitis or other major complications
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34
Q

Code of Practice- Obligations

(Notifiable/Non-notifiable)

A
  • we DO have a duty to the country especially in regards to diseases
  • as vets we are responsible for notifiable diseases
  • EIA: is not in the UK (exotic), any of the horses that have it (or positive serology) will get euthanased, should not be coming into the country, but it IS in europe (can periodically get horses testing positive)
  • if it is a domestic horse, likely hasnt been exposed - maybe still good to check
  • thoroughbred - still HAS to be tested for it by regulation
  • EVA: also a notifiable disease! STD- from the stallion
  • CEM: one of the areaswe want to be swabbing for. can sometimes show up as random positives (low levels of posiitves in the country- possible from fomites from teasing stallions) , is notifiable!

there is a testing regime for some non-notifiable diseases and they are just as important!

  • still need to have clear Klebsiella and pseudomonas
  • these two along with CEM are tested on the same swabs
  • Strangles- a lot of studs will ask for vaccination clearance before even allowing horses on
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35
Q

Code of Practice- Obligations

(testing)

A
  • our two blood diseases that need to be tested for
  • EVA and EIA - need to know she is clean before she goes to the stud and we also have a duty to report these!
  • important to swab the clitoral sinus and fossa of the horse!
  • edometrial swab will be done every cycle where as the other tests (and exam of the male) will be done at the beginning of the season
  • do before each covering as well as oyu do not want the stallion to stick it in and touch the covering if there are all bugs
  • and vise versa, by having a mare infected by a stallion
  • If she cycle and misses, you just need to redo the endometrial swab
36
Q

Clitoral Swab

A
  • DO FOSSA AND SINUS
  • either do PCR or culture (takes longer- 7 days)
  • swab needs to be in date and shipped correctly and at lab within 48 hours
  • PCR is not acceptable for horses going into USA - need to do a CEM and needs to go to government labs (not local) and will need t be chilled or they will send it home
37
Q

HBLB Testing: Mare Requirements

A
  • this sheet would be acceptable for local breeding
  • If they have endometritis from another bug, this is not going to pick it up
  • this is only picking up CEM, Pseudomonas and Klebsiella
  • It will only pick up those 3
  • mare will only be able to be bred if they have this
38
Q

HBLB Code of Practice: Additional Requirements

(EHV3)

A
  • can be transferred via fomites (sponges, flies)
  • can be classically be spread by teasing stallion
  • highly contagious
  • it is a limiting disease, but it is really important for us to take care of in the breeding individual
39
Q

HBLB Code of Practice: “Genital Glanders”

A
  • we dont have here, was last seen in italy
  • something we don’t test for with local breeding, but if they are traveling
  • more concerned for horses coming from the far side of europe - should be cleared before, but doesnt always happen
40
Q

HBLB Code of Practice

(Strangles: Streptococcus equi)

A
41
Q

Pre Breeding Exam

A
  • can use bales (put something between you and the horse!)
  • not everyone will have a crush
  • sedated mares will kick you a lot faster and harder as they are not aware, it is just a reflex!
  • You need to sedate a horse efficiently to coduct an exam efficiently
  • particularly young mares don’t have a lot of room, you need to be cautious - if they are straining, let off a bit
42
Q

Pre Breeding Exam

(External genitalia)

A
  • benched appearance: when she defecates, it will go right into the vulval area
  • we can create an artificial seal
43
Q

Pre Breeding Exam:

Ultrasound

A
  • dominant follicle–> thickening –> CL
44
Q

Pre Breeding Exam: US

(Uterus)

A
  • orange pattern tells you have an oestrus uterus
45
Q

Pre Breeding Exam: US

(Uterus Abnormalities)

A
46
Q

Pre Breeding Exam: US

(record findings)

A
  • can do different things, but need to keep some sort of record!
  • need to have a record of what you do as well
47
Q

Pre Breeding Exam: Cervical and Vaginal Exam

(Vaginal Speculum)

A
  • now do a speculum exam
  • need to clean all the crevices (clean hand/dirty hand method)
  • do not want to create an iatrogenic infection
  • oestral cervix: red and oedemetous
  • porr conformation can really end up with secondary infection
  • dioestral cervix can mean she might have a CL which will affect her being in true oestrus - give PGF2a and then she may stand more effectively
48
Q

Pre Breeding Exam: Endometrial Swab

A
49
Q

Pre Breeding Exam: Endometrial Swab

(steps)

A
  • this test is not particularly good for picking up a fungus, probably better to do a flush to pick up fungus
  • make sure the swab punches all the way through when you do it! - so all can be nice and safe
50
Q

Breeding Plan

A
  • once vaccination records and pre-breeding swabs pass
  • can send her to the stud
  • point now is going to be working out when you are going to be able to breed her - need to know if we have a CL, follicle,etc.
  • need to know if the family or staff is going to be away as well to schedule correct foaling time and arrival of semen (can be restricted by travel)
  • we will know there is a CL there if we have a diestral uterus and diestral cervix
  • so we do our scan after discussion, give her the PG and get her into oestrus
  • we know our oestrous is goign to be 5-7 days
  • some mares reliably put up more than one follicle, we need to keep record of that in the case of possible twinning if we give her an ovulation drug
51
Q

Breeding PLan (2)

A

Post overing Exam: see what follicles have ovulated and if there is none it is best to remate her

  • If the follicles grow 3mm a day then you can pretty much guess how long till ovulation (estimate) if you have a scanned a 3cm follicle
  • you MUST time the semen delivery right or else you may just watch her ovulate and then have nothing to service her with
  • stallions can only really serve 3-4 mares a day, so you may have to end up picking if you had 5 to get served on who you can push forward, who is closest in distance, etc. - will help the stud!
  • can help with ovuplant to get more time (will encourage ovulation in 48 hours)
  • may use hCG if you want to push them a little faster
  • post covering exam: going to want to know what ovulated (if they didnt then you need to rebreed her), how many ovulated (so you can check for CL later but also twins)
  • but also check how much fluid is left! - may need to push some of that fluid out - can use oxtocin or lavage the uterus (UL can be routine in some yards)
52
Q

Breeding: Natural Cover

A
  • mares can get really badly hurt as they don’t know what they are doing and arent cycling properly
  • use a teaser stallion to find mares in season - unfortunately would be the ones to recieve a kick
  • stallions can get kicked in the legs, nuts, etc.
  • but a lot of the natural running with the stallion services have less injuries than the hand served - they know what is going on
53
Q

Breeding: Natural Cover

(disadvantages)

A
  • everyone is more potentially more at risk
  • professional studs: a lot of these stallions are fine and just walk in and do their thing
  • some stallions are not nice to cover
  • stallions can only cover maximum of 4 mares a day
  • mare with young foals, they become extra cautious –> need to remove the foal and put them at eyesight (but then the mare performs badly still sometimes)
  • also there is a biosecurity risk as you are bringing the foal out into the environment of the stud where they may have contact with other horses - much easier to spread disease that way!
  • so some will breed the boarding mares before the walk in mares (keep them spearate in the services for the day!)
54
Q

Breeding: Foal Heat

A
  • this is the first cycle they have after the mare has foaled
  • much lower conception rate at the first cycle
  • It gets better as you let more cycles through (you can also short cycle her with the Prostaglandin)
  • need time to reorganize –> day 5 or 6 may be too soon and would lead to a poor conception rate
  • Some people like breeding on the foal heat as you bring her forward a week or two - shortening up the foal cycling and you can bring the coneption rate forward
  • if you short cycle her off at day 5 after foal heat, then she will only be in cycle again day 14 or so after foaling (puts it all a bit behind)
  • If mares miss the first couple of cycles - their foals are getting later, later and later and then may have to have an empty season if it gets too late for sales,etc.
55
Q

Natural Cover vs. Artificial Insemination

A

AI: can cover more mares per breeding season

  • a lot of it relies on timing the correct arrival of semen with your mare being in oestrus
  • Everyone wants to blame the mare with failed AI’s but often it has to do with transport
56
Q

Artificial Insemination: Chilled Semen

A
  • want to get it chilled down (to 4 degrees) and shipped if you are going to send it a distance and breed a mare in 24 hours
  • If you are taking it near by (2-3 hours drive) and intend to use it right away then you probably don’t need to chill it
  • semen is incredibly sensitive! –> need to put in an extender
  • put in a completely insulated container
  • frozen semen doesnt last as long - can last probably about 36 hours
  • If it has spent too long in transport, it will begin to slowly die as the packs melt
57
Q

AI: Timing

A
  • fresh semen we have some more wiggle room
  • Ideally want to get it within 6 hours of oestrus
  • As long as you are getting the semen in as close to ovulation as possible
58
Q

AI: Chilled Semen and Mare Cycle

A
  • looking for progressively motile sperm
59
Q

AI: Chilled Semen

(stallion)

A
  • all semen must be accompanied by export papers
  • it must be the original copy! - needs to accompany the semen
60
Q

AI: chilled semen

(application)

A
61
Q

Principles of Semen Handling

A
  • transit issues and temperature can damage the tail and overall semen motility –> won’t be “moving forward” on exam due to thermal damage to the tail
  • ideally want to warm up the chilled semen a bit before AI, but some vets don’t do this (especially if there are some time constraints with the arrival of the semen)
62
Q

Semen Handling: Assessment

A
63
Q

Frozen Semen Insemination

A
  • frozen semen is handy to have as you can time AI for the mares better
  • conceptions rates appear to be as good for chilled semen as they are for frozen
64
Q

Frozen Semen Technique

A
  • in this technique you are basically using your ovulation drugs to control it
  • can administer all the semen after ovulation

OR

  • you can do split dosing - do it at set times based on when you gave the ovulation drug - more controlled
  • nice because then you won’t have to be palpating the mares through the night checking for ovulation
65
Q

Frozen Semen Handling:

Safety

A
  • Liquid Nitrogen can explode!
  • don’t want to get semen in the eye.. lol
  • try and thaw them out in the water bath
  • DEFA will go after you without proper paperwork
66
Q

Frozen Semen Handling:

Storage

A
67
Q

Frozen Semen Insemination Techniques

A
  • can go into the uterine body just like for AI
  • or you can go into the uterine horns
68
Q

Uterine Lavage

A
  • inflammation in the uterus that we want to try and get out
  • especially important for the frozen semen because the extender solution in the frozen semen is basically anti-freeze - sometimes the mares will react to the extender in the semen!
  • same with chilled semen extender
  • since with these methods we don’t have pheramones (from teaser stallion), the mares will not be producing oxytocin to help shed out all this - important for us to remember!
69
Q

Method of Uterine Lavage

A
  • essentially fluid in and fluid out
70
Q

Endometrial Biopsy

A
  • uterine biopsy forceps essentially take out a bit of the endometrium and then we can assess if there are issues such as endometriosis (damage in the uterus)
  • endometritis is inflammation of the uterus
71
Q

Kenney Biopsy Scale

A
72
Q

Caslick’s Vulvoplasty

A
  • injecting local anaesthetic and then making a new wound
  • going from slopey benched appearance to making a new opening - new vaginal opening
  • will also need to be cut before foaling since we have closed it
  • will likely need to be cut a bit before breeding as well - especially if using natural cover (may just need to remove a few stitches)
  • make sure to stitch back up after to avoid aspiration or pneumovagina
73
Q

Diseases: Equine Infectious Anaemia

A
74
Q

Diseases: Equine Viral Arteritis

A
75
Q

Equine VIral Arteritis

A
76
Q

Diseases: Contagious Equine Metritis

Klebsiella pneumoniae & Pseudomonas aeruginosa

A
77
Q

Diseases: Contagious Equine Metritis

A
78
Q

Diseases:

Klebsiella pneumoniae & Pseudomonas aeruginosa

A
79
Q

Diseases: Contagious Equine Metritis

Klebsiella pneumoniae & Pseudomonas aeruginosa

A
80
Q

Diseases: Contagious Equine Metritis

Klebsiella pneumoniae & Pseudomonas aeruginosa

(stallion Treatment)

A
81
Q

Diseases: EHV 1,4

A
82
Q

Diseases: EHV-1 (4) Abortion

A
83
Q

Diseases: EHV-1 (4) Prevention

A
84
Q

Diseases: EHV-1 (4) Vaccination

A
85
Q

Phimosis

A
  • inability to extrude the penis
86
Q

paraphimosis

A
  • inability to retract the penis into the prepuce
  • can be a consequence of using ACP in a colt
  • swelling and oedema of the penis/prepuce will start to compromise the dorsal artery
  • can lead to penile paralysis
87
Q

priapism

A
  • peristent erection