Equine reproduction Flashcards
How long is the mares normal oestrous cycle?
21 days
How long is the mares normal oestrus?
2-7 days
What are counted as high risk mares?
Previously positive mares
Travelling outside UK
What do you swab horses for?
Contagious equine metritis - notifiable
Pseudomonas
Klebsiella
What causes contagious equine metritis?
Taylorella equigenitalis
What is a sign of active CEM infection?
Purulent discharge
What are the two types of culture used for the swabs?
Aerobic and microaerophilic
What are the two notifiable diseases that are detected by serology?
Equine viral arteritis
Equine infectious anaemia
What does a seropositive infection mean for equine infectious anaemia?
Definite infection
Unlike equine viral arteritis which has a vaccination
What is the ideal perineal conformation?
Vulva 0-10 degrees from vertical
3/4 of the vulva below the pelvic brim - top open
Mostly vertical
Have a vulval seal
What are the steps of a breeding soundness exam?
Prebreeding swabs General clinical exam Repro clinical exam - Check perineal conformation Rectal ovarian palpation and US Check vestibule, vagina and cervix Endometrial swabs
What are the different breeding methods in mares?
Natural covering
Fresh, chilled and frozen AI
Deep intrauterine insemination
When is deep intrauterine insemination used?
When mares react badly to AI and get endometriosis
How do you predict ovulation?
Follicle - 4-5cm
Oedema pattern on ultrasound
Flattening/softening of cervix
How to bring forward the spring transition into oestrous?
Administer progestagens and then withdraw them - altrenogest
How do you shorten the luteal cycle?
Use synthetic progesterone - estrumate
What is required to be able to shorten the luteal phase of the oestrus cycle?
Need a mature CL
How do you prevent oestrus?
Oral altrenogest
GnRH vaccine
How do you treat endometritis?
Flush sterile saline and oxytocin/prostaglandins
What causes infectious endometritis?
Commensals - common
Taylorella/klebsiella/pseudomonas
Yeast
Fungi
What are the main causes of poor fertility in horses?
Erratic oestrus
Persistent CL
Anovulatory follicle
Granulosa cell tumour
What electrolytes increase before foaling?
Calcium
Potassium
What is the rule of 3 when foaling?
Stand by 1, suckle by 2, pass placenta by 3
What events occur post partum?
Uterine involution
Foal heat - 5-9 days
How do you induce parturition?
Low dose oxytoxin
What is red bag delivery?
Allantochorion is passed before the foal is delivered - premature placental separation
When does it count as dystocia?
When the allantochorion ruptures but
No foal/amnion at vulva in 5 mins
No strong contractions at 10 mins
When should you stop vaginal assisted delivery?
When there has been no progress in 5 mins
What does clenbuterol do?
Stops uterine contractions
How do you treat retained foetal membranes?
Oxytocin
Manual traction
What can retained foetal membranes cause?
Endometritis
Laminitis
Shock
Death
What is a first degree perineal laceration?
Just the vulval lips
What is a second degree perineal laceration?
Vulval lips and muscle layers
What is a third degree perineal laceration?
Common opening between vulva and anus
Complete disruption of rectovestibular shelf
When should you inspect for cervical trauma?
Dioestrus
What can post partum colic mean?
Uterine haematoma
Hypocalcaemia
What are the symptoms of hypocalcaemia?
Dry faeces
Spontaneous diaphragmatic flutter
Tetanic spasms
What is an issue with premature lactation?
Potential for failure of passive transfer to foal
collect colostrum
Check for placentitis
How can you diagnose pregnancy in a mare before 21 days?
Transrectal ultrasound - from d12
Elevated plasma progesterone
Failure to return to oestrus
When can you perform transrectal palpation to diagnose pregnancy?
From 21 days
What can you measure in a blood test to diagnose pregnancy in a mare from 60 days?
Plasma equine chorionic gonadotrophin
When does the foetus go out of reach?
85 days
What is the difference between a pregnancy and a cyst?
Pregnancy is spherical, specular reflections
Cyst is irregular
How do you check for twins?
Check for 1 or 2 CL
Can also US or manually palpate
How are twins managed in the mare?
Manual rupture - pinch
(Separate if not implanted to prevent killing both
Or abort both with PG
What are the risks with pregnancy diagnosis?
Rectal tears
Risk of killing both
Abortion
How can you tell if there is a rectal tear?
Blood on rectal glove
Sudden loss of rectal tone
What are the risk factors for rectal tears?
Rectal examination
Dystocia
Age
Breed
How can you reduce the risk of rectal tears?
Sedation, relaxants - buscopan
What should you do if there is a rectal tear?
Admit to owner immediately
ABs, NSAIDs
Absorbent packing
Referral
What produces progesterone in horses?
Prim/secondary CLs initially
Then supported by equine chorionic gonadotrophin from endometrial cups
Up until what point can you do intended abortion by vet?
<35 days - until endometrial cups form
How does oestrus next present after embryo loss at 5-15 days?
Early return to oestrus
How does oestrus next present after embryo loss at 16-36 days?
6 weeks after luteolysis of primary CL
How does oestrus next present after embryo loss at 36-140 days?
5 months after luteolysis of secondary CL
What are the 3 main infectious causes of abortion in mares?
Bacterial placentitis
Equine herpes virus
Equine viral arteritis
What are the clinical signs of bacterial placentitis?
Vulval discharge
Premature lactation
Abortion
HOw do you diagnose bacterial placentitis?
Measure thickness of uterus and placenta
Swab cervix
What is the main pathogen causing bacterial placentitis?
Strep zooepidemicus
Which type of equine herpes virus is most likely to cause abortion?
EHV-1
What is important in the treatment of EHV-1?
Aborted foetus is highly contagious to other mares so dispose correctly