Equine Repro and Neonatology Flashcards
Over what age is classed as a mare?
> 4 years
Puberty at 12-24 months
How does a mare cycle?
It will struggle- ha hey
Long day
Seasonal polyoestrus
How long does the oestrus cycle last?
When does Diestrus/Oestrus occur?
Oestrus cycle- 21 days
Dioestrus- 16-17 dYS
Oestrus- 4-6 days
What is the equine transition period?
- Period of change from anoestrus to regular cycling
- Lasts upto 6 weeks
- Ovaries have multiple small follicles
- Can show no oestrus, constant or erratic oestrus
- Follicles will not ovulate
What can the following drugs be used to manipulate in oestrus?
1. Prostaglandins
2. Prostagens
3. Oestrogens
4. Chorionic gonadotrophin
5. Desleroelin
- Prostaglandins- induce luteolysis of CL: oestrus 3-5 days post injection
- Given orally suppress oestrus, withdrawal causes rebound activity
- Oestrogens: induce behavioural oestrus: AI collection
- Given during oestrus: induce the dominant follicle
- Hormone sub-cut induce ovulation within 48h
How can the photoperiod be used to manipulate oestrus?
- Can be brought forward by artificial light over winter
- Mares ovulate 8-10 weeks later
How can oestrus be suppressed?
- Long term progestagens- spenny
- Intrauterine devices- not encouraged
- Anti-GnRH vaccine- not licensed
- Induce long term CL- oxytocin
- Put in foal and terminate
- Ovariectomy: invasive, expensive
When should mares be served?
- Oestrus behaviour ceases within 24 hours of ovulation: mare no longer receptive
- Ooctye viable for 12 hours post ovualtion
- Matings after ovulation have poor conception
- Spermatozoa reach oviduct within hours and are viable for 48 hours
Serve mares 24-48 hours prior to ovulation
What structures will a mare in oestrus have?
- Dominant follicle
- Uterine oedema
- Soft oedematous cervix
- Behavioural signs of oestrus
If in oestrus scan 24-48h later
If not give PG: 3-5 days
What are the signs ovulation is abour to occur?
- Numerous to dominant follicle
- Dominant follicle- pointing (imminent)
Ovulated leaving corpus haemorrhagicum- CL
- If follicle >35mm, uterine oedema regressing: MATE
What should be scanned post mating?
- 12-24 hours after
- See if ovulated
- Check for one ovulation: twins
- Fluid in uterine lumen: endometritis
What does bad perineal conformation lead to?
- Failure of vulval and vestibular seal
- Pnuemovagina
- Cervicitis
- Bacterial contamination
- Endometritis
How can perineal conformation be altered?
Caslicks vulcoplasty
* Closure of vulva
* Requires opening before foaling
What ovarian problems can occur?
Persistent CL- tx: PG
Anovulatory follicles: tx PG/time
Granulosa cell tumour- lymphomania or anoestrus: AMH
Whar are the effects of endometritis?
Does not affect conception but implantation
Chronic metritis, free fluid, mating induced endometritis
How is endometritis treated?
- Uterine lavage: volumes of saline
- Oxytocin
- Intrauterine ABs
- Use of AI
What is chronic degenerative endometrial disease?
Endometriosis
* Progressive degen of endometrium and replacement by fibrotic tissue
* Age related infertility
DX: hisopath
TX: none/curette
- What causes cervical incompetence?
- What are the problems with uterine cysts?
- Either congenital or foaling injury- Sx
- Rarely cause infertility, can cause problems at preg- remain static in size
What pre-breeding diseases are cleared?
- Clitoral swab for CEM: contagious equine metritis
- Blood sample for EVA: equine viral arteritis
- Strangles
How long is a horse pregnant?
336 days average
What do endometrial cups do?
- Endometrial cups start secreting eCG at day 35 pregnancy
- eCG maintains primary CL and encourdages secondary
- At day 70 eCG falls and cups gone by 150d
- After 200 days- foetal-placental progesterone maintains prengancy
What is the importance of endometrial cups in equine repro?
- Once in place- >35 days can only be removed by natural regression- 150d
- Abbortion must be done <35d if want to breed in same season
How is PD done in horse?
- Failure to return to oestrus: 14-21d
- Lab- eCG from 45-90
- Manual palp- 40d
- Rectal- >14 days, 26d
What are the common causes of pregnancy failure?
- Early loss <40d (10-14 highest)
- Viral- EHV (most common), EVA
- Bacterial- ascending infection
- Fungal- rare
- Twins- opposite horns issue
- Idiopathic
- Foetal abnormalities
- Systemic illness- pyrexia
How can abortion be induced?
1. Before 3 months
2. After 3 months
- PG
- Repeated PG
How can foaling be induced?
What are the risks?
Oxtocin every 15-20 mins until delivery starts
Risks
* uterine rupture
* Dystocia
* Foal immaturity
* RFM
What are the physical characeteristics of prematurity/dysmaturity?
- Low birth weight
- Short, silky hair
- Floppy ears
- Domed head
- Weakness
- Flexor tendon laxity
- Incomplete ossificaiton of tarsal/carpal bones
- Severe cases: organ dysfunction
What predisoposes to FPT?
- Loss of colostrum via premature lactation
- Inadequate colostrum
- Failure to ingest
- Failure to absorb
How is FPT diagnosed?
- RIP
- ELISA- snap test
- TSP- globulins
How is FPT treated?
- > 12-24 h need plasma
- <12-24- colostrum: banks, commerical
What are the consequences of FPT?
- Sepitcaemia
foals normally stand within 1 hour and suck within 2
What is the average weight of newborn foal?
45-55kg
What is required for sick neonate?
- Intense medical care- fluid, ABs, IGg, NSAIDs
- Resp stimulatit
- Diuretics- oliguria
- Resp support
- Monitor
ABs- penicillins/b-lactams
What are the clinical signs of neonatal septicaemia?
- Foal off suck
- increased RR and effort
- Acute severe lameness
- Discharge/swollen umbilicus
- Fever
- Dark MMS
- Diarrhoea
- Meninigtis
- SIRs
What are the three localisations of sepsis infections?
Umbilical- US
Pneumoina- Blood gas, X-ray
Arthritis- synovial fluid
What are the differentials for neonate with resp signs?
- Septicaemia
- Viral pneumonia
- Meconium aspiration
- Haemothorax
- Respiratory distress syndrome
- Pulmonry hypertension
- Central resp depression
What is CID/SCID?
Severe combined immunodeficiency
* Failure to produce functional B/T lymphocytes
What is ‘dummy’ foal?
Peinatal aschphyxia syndrome
* Ishaemia, Oedema and reperfusion injury to brain, Kidney
* due to in utero hypoxia
How is PAS treated?
dummy foal
Mannitol if cerebral oedema
Compression squeeze
Control of seizures
What are the clinical signs of ruptured bladder?
Most common in colts- 2-3d
Dysuria- stranguria
Post-renal zotaemia/ US
Medical managemnt first
What are the differentials for foal colic?
- Meconium impaction
- Ruptured bladder/uroperitoneum
- Overfeed
- Diarhorrea
- Gastric ulcers
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What are the differentials for foal anaemia?
- Blood loss- low protein
- Haemolysis- normal protein
What causes neonatal isoerythrolysis?
Aa and Qa negative mares to positive stallions
How is neonatal isoerythrolysis diagnosed?
Detecteding Abs on RBCs (coombs test)
How is neonatal isoerythrolysis prevented?
Withhold colostrum
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How is Neonatal isoerythrolysis treated?
PCV >15% remove source
<15% Blood transfusion
Supportive care
What are the differentials for foal diarhorrea?
E.coli
Salmonella
Clostridia- smells bad
Foal heat diarrhoea
What are the differentials for foals >10 days?
- rota virus
- Corona/adeno- immunocompromised
- Crypto
- Rhodococcus
- Lawsonia intracellularis
When does rotavirus affect foals?
1-4 weeks of age
Highlt infectious- outbreas
What causes equine proliferative enteropathy?
- Lawsonia intracellularis
3-11months
TX: erythromycin/oxytet
