Small Ruminants: Diseases of Peri-parturient Ewes Flashcards
What are the different BCS for peri-partutrient ewes in different systems?
What are the possible problems for sheep from nutrition around lambing time?
- Metabolic disease- twin lamb, hypocalcaemia, hypomagnesaemia
- Ewe- mastitis, dystocia, maternal behaviour
- Lamb mortality- low birth weight, poor colostrum and milk productoin
What are the general principles of pre-tupping ewe feeding?
What is flushing?
- Weaned early summer
- Summer grazing to recover
- Flushing is increasing feed to ewes before mating to increase BCS which improves the number of eggs produced
What should a ewe be fed from early to mid pregnancy?
- Early pregnancy no change
- Mid pregnancy- placenta develops maintain BCS or lose 0.5
- If underfed small placenta and low birth weight
What are the principles to nutrition 90 days to lambing?
Nutrition absolutetly crucial
* During the last 6 weeks of gestation 70% of foetal growth is occuring
* Mammary development
* Rumen capacity is decreasing
* Support foetal growth, mammary production, ewe health (ketosis)
What are the principles for ewe nutrition in late pregnancy?
- Ewes into feeding groups
- Ration- good quality forage ad lib, concentrate requirments based on forage max 1kg day
- Water
- Consider vitamins and minerals
- Trough space- equal for all ewes
- Pen first timers seperately
- Consider floor feeding concentrates
- Total mixed ration
- Monitor
When do lambs start eating grass and when are they weaned?
- Start eating grass at 6 weeks
- Weaned about 12-16 weeks of age
What happens when ewe nutrition during lactation is wrong?
Often causes mastitis
Poor lamb growth
Susceptible to disease
Concentrate feed depends on the number of lambs and grass availability
What happens when ewe feeding during lactation is wrong?
Often causes mastitis
Poor lamb growth
Susceptible to disease
Concentrate feed depends on the number of lambs and grass availability
What are the common problems you may come across with sheep nutrition around lambing?
- Thin ewes
- Forage- poor qual, trough space
- Concentrates- quality, too much (acidosis)
- High stocking rates/overcrowding
- No access to water
What is the problem with fat ewes for lambing?
- More prone to pregnancy toxaemia
- More dystocia
- Increased prolapse
- Large foetus cause dystocia
- Oversized lambs have higher mortality
- Fat is expensive
What is pregnancy toxaemia?
What are the risk factors?
Energy deficiency, hypoglycaemia, hyperketonaemia
RF:
* Late pregnancy
* Thin ewes
* Fat ewes
* Stress
* Broken mouth
* Concurrent disease
* Multiple foetuses
* Inadequate diet
* Change in diet
What are the clinical signs of pregnancy toxaemia and how is it diagnosed?
CS: seperate from group, inappetant, central blindness, tremors face and ears, hyperaesthesia, stargazing, progress to recumbancy, death
Diagnosis- clinical signs, BOBHB >1.1mmol subclinical, BOHB >3mmol clinical signs
How should the flock be treated and more prevented with pregnancy toxaemia?
- Review nutrition urgently
- Separate out thin or older ewes
- Ad lib treacle/molasses
Prevention
* Ensure adequate feeding- feed based off no of foetuses, BCS 6-8 before lambing, avoid sudden change
* Monitor ketone levels
* Don’t keep old ewes
What is hypocalcaemia?
Increased demand of foetus and colostrum for calcium, mobilise calcium from bones
Usually prelambing 6 weeks onwards
Often stress induced
Other risk factors- acidosis cereal diet, older ewes, rapid growing pasture
What are the clinical signs of hypocalcaemia, how is it diagnosed and treated?
CS: initial weakness and exitment, progress to recumbant, dilated puils, bloated, comatose, death
Confirm diagnosis- blood sample
Treatment- slow IV 40-80ml 20%, rapid response, slow cut 1ml/kg
Monitor as may relapse
What is staggers?
Hypomagnesaemia- insuficeint Mg
History- post lambing, peak lactation, lush grass
CS: rapid onset, neurological symptoms, exitable, tremors, convulsions death
Diagnosis- history and clinical signs
Treatment- 20-40ml 25% MgSo4 s.c
What are the different diagnosis of sick/recumbant ewes at lambing times
- Hypocalcaemia
- Pregnancy tozaemia
- Hypomagnesaemia
- Listeria
- Mastitis
- Metritis
- Bloat
- Pasturellosis
- Poisoning
- Acidosis
What is the approach to a ewe in dystocia?
History, examination, obsetrical assessment
What can be used to assist with a ewe in dystocia?
wear gloves
Use NSAIDs
Use Epidurals
Use ABs
Give lamb colostrum
Describe how to do a simple embryotomy?
Dead lambs not possible to deliver per vaginum
1. Lots of lubrication
2. Cut through skin round leg above carpus
3. Up towards elbow, pull leg off and repeat
What should be looked at if deaths on farm are dystocia related?
- Farm history and PM of ewe and/or lambs
- Look at- age of ewes, breeds, conditions of ewes, hygiene, staff
What are the indications and contraindications for caesarean?
Indications- oversized lamb, ring womb, vaginal prolapse, foetal monster, mal presentation
Contra-indicatoins- rotten lamb, smelly fluids
Describe the process of a caesarean
Briefly
- Anaesthesia- local procaine + sacro coccygeal epidural
- Incision- half way between last rib and wing of ilium 10-15cm below transverse
- 15cm incision- skin, subcut, external/internal ab, transverse ab, peritoneum
- Grasp uterine horn and exteriorise, incise 10-12cm, remove lamb
- Suture- continuous inverting pattern, cat gut, simple cont on muscle, skin forward interlocking
- Give LB ABs and NSAIDs
What causes metritis?
What are the clinical signs?
How is it treated?
- Metritis is an oppertunistic infection of environmental bacteria- incl clostridium tetani
- Caused by dystocia and post abortion
- CS: dull depressed, recumbant, toxaemia, congested MMs, red/brown purulent discharge
- ABs and NSAIDs, guarded necrosis
When is a vaginal prolapse most common?
What causes it?
How is it treated?
Common in last 4 weeks of pregnancy 1-2%
Vagina ± cervix and bladdder
Causes- breeds, litter size, age, history, nutritional, slopes
Mild and uncomplicated cases can use retention devices
Surgical treatment
Describe how to surgically treat a vaginal prolapse?
- Epidural- stops straining (sacrococcygeal) 1.75ml procaine
- NSAIDs and ABs
- Clean and assess
- Replace prolaspe- palm, raise back end
- Suture- obsterical tape, purse string
- Mark and remove before lambing
- Cull
What causes an intestinal prolapse?
Vaginal wall breaks down
Fatal, euthanise
What casues a uterine prolapse?
How is it treated?
Excessive traction at lambing, hypocalcaemia
Treatment- epidural, clean, remove placenta, replace carefully, suture, ABs, NSAIDs
What are the three presentations of mastitis?
- Peracute/gangrenous/toxic
- Acute
- Chronic
- When does peracute/gangrenous mastitis occur?
- How does the ewe present?
- How does the udder and milk appear?
- Immediately post lambing 4-8 weeks
- Ewe is sick, tachycardic, rumen stasis, inappetant, lame, hungry lambs
- Udder swollen, cold blue, milk is severly discoloured
- When does acute mastitis occur?
- How does the ewe present?
- How does the milk appear?
- Immediately post lambing
- Ewe- fever, lame, hungry lambs, udder red, painful, swollen
- Milk- clots, discoloured
How does chronic mastitis occur?
When is it usually detected?
Often detected when ewe is dry at weaning or culling
Udder abscesses, swollen or light purulent discharge from teats
Ewe not systemically ill
What are the main organisms that cause mastitis in sheep?
- Stapholoccus aureus- teat skin
- Manhaemia haemolytica- lambs mouths
- Also- streptococcus, E.coli, A. pyogenes
What are the risk factors for mastitis in sheep?
- Nutrition- under in late pregnancy and lactation
- Concurrent disease- Johne’s
- Prolificacy- multiple lambs
- Age
- Udder conformation- abnormal teat position
- Teat lesions- orf, chapping, over sucking
- Genetic
- Hygiene
- Milking practices- dairy sheep
How are the different presentatins of mastitis treated?
- Prompt
- Gangrenous- euthanasia if ewe saved will be culled
- Acute- systemic ABs, cult/sen, first line try amoxycillin 5 days, stripping of udder, NSAIDs, IV fluids, TLC
- Chronic- culling
What is current advice for mastitis prevention?
- Ensure adequate ewe nutrition pre and post lambing
- Ensure good lamb nutrition
- Wean lambs abrubtly at 12 weeks
- Control orf
- Control concurrent diseases
- Dont turn out ewes with triplets
- Cull ewes over 7, udder lumpbs, broken mouthed, abnormal teat position
- Ensure good bedding hygiene in sheds
- Review breeding policies
What causes teat lesions?
Over sucking
Chilling
Poor conformation
Orf
Secondary bacterial infection travels up teat and causes mastitis
