Diseases of the Peri Parturient Ewe 1

List some of the main metabolic diseases associated with nutrition around lambing time

Metabolic disease

• Pregnancy toxaemia / twin lamb diseaes

• Hypocalcaemia

• Hypomagnesaemia

What are the secondary diseases associated with nutrition around lambing time?

• Ewe

  • Mastitis

  • Dystocia

  • Maternal behaviour

• Lamb mortality/ morbidity

  • Low lamb birth weight

  • Poor colostrum

  • Poor milk production

Recall the body condition score targets for the different stratifications and different points in the production year

What are the general principles of feeding ewes at each stage?

• Pre tupping: summer grazing to recover at pasture before tupping, if flushing inc feed will improve number of eggs produced

• Early to mid pregnancy: no sudden changes, maintain BCS

• 90 days to lambing: nutrition absolutely crucial to health

• Late pregnancy: support foetal growth and maintain ewe health to avoid ketosis

What non metabolic issues is underfeeding in late pregnancy related to?

• Mastitis during lactation

• Maternal behaviour

When do a lot of farms supplementary feed in a ewe's pregnancy?

• Last 6-8 weeks pregnancy

  • Later lambing with well managed grass may be okay without

• Forage and/or concentrate

  • Good access to top quality forage is key

What are some of the principles of nutrition that are implemented in a nutrition plan for ewes during pregnancy?

1. Split into feeding groups (BCS, Lambing dates, Young ewes separate, Scanned singles/twins)

2. Ration

3. Water

4. Vitamins and minerals (farm specific

5. Trough space

6. Pen first time lambers separate

7. TMR

8. Monitor- BCS, Ewe Health, Metabolic Profiles

What does a typical ration look like in late pregnancy for a ewe?

• Ad lib good quality forage

• Conc requirement based on analysis of ^^

  • Typically max 1kg per day and 0.5kg per feed

What are the trough space reccomendations for late pregnancy ewes? Why is it so important

• Concentrates all sheep feed at once

• Forage (ad lib) 1/3 sheep feed at once

If not followed fat get fatter, thing get thinner

At what age do lambs start eating grass? When are they weaned?

• Lambs start eating grass 6 weeks age

• Weaned about 12-16 weeks old

What will poor feeding in lactation lead to?

• Mastitis in ewes

• Poor growth in lambs

• Susceptible to other diseases

How can you evaluate whether you need to supplement concentrates in a lactating ewe?

• Can use sward height

What diseases may arise if nutrition is not adequate in peri parturient ewes?

• Twin Lamb Disease

• Hypocalcaemia

• Lamb mortality/morbidity

  • Weak small lambs at birth

  • Watery mouth

  • Joint ill/ infections

  • Hypothermia

• Mastitis

• Lamb Growth

List some common problems you may come across with sheep nutrition around lambing time

• Thin ewes- inadequate nutrition

• Forage- poor quality, spoiled, not ad lib, insufficient trough space

• Concentrates- inadequate trough space, poor quality, too much (acidosis)

• High stocking rates/ overcrowding

• No access to water

If a ewe is fat what does this make it susceptible to? (doesn't tend to be a problem in commercial sheep flocks)

• Pregnancy toxaemia

• Dystocia

• Prolapse

• Higher lamb mortality

What is the main cause of pregnancy toxaemia?

• Energy deficiency

  • Hypoglycaemia

  • Hyperketonaemia

List some of the risk factors of pregnancy toxaemia

• Late Pregnancy (last 6 weeks)

• Thin ewes (<BCS 2.0)

• Fat ewes (>BCS 4.0)

• Stress

• Broken mouth

• Concurrent disease ( fluke, worms)

• Multiple foetuses

• Inadequate diet

• Change in diet

What are the clinical signs of pregnancy toxaemia?

Caused by lack of glucose in cerebrum and toxic effects of ketones

• Separate from group

• Inappetant

• Central blindeness

• Tremors face and ears

• Hyperaesthesia

• Head, pressing, star gazing, persistent drinking)

• Progress of recumbency

• Death

• 0-10 days

How is pregnancy toxaemia diagnosed?

• Clinical signs

• BOHB > 1.1 mmol/l = abnormal/ subclinical

• BOHB >3 mmol/l = clinical signs

How would you treat preganancy toxaemia?

• Separate, provide highly palatable feed

• IV glucose 50-100ml 40% dextrose

• Propylene glycol 120ml BID for first day, 60 ml BID after this

• Ca supplementation

• NSAID

• Check for concurrent disease

If a case of pregnancy toxaemia is not improving what would you do?

• Consider stage of pregnancy

  • Abort ewe (<135 days) or Induce labour (>135 days)

• PTS

How may you treat the flock if there is a case of pregnancy toxaemia?

• Review nutrition

• Separate thin or older ewes

• Ad lib treacle/ molasses

How do you prevent pregnancy toxaemia?

• Ensure adequate feeding - BCS, avoid sudden changes

• Monitor ketone body levels 2-3 weeks before lambing

• Don't keep old broken mouth ewes

• Manage concurrent disease

How do you monitor ketobe body levels?

Blood sample for Beta hydroxy butyrate

Explain the pathogenesis of hypocalcaemia in sheep?

• Increased demand of foetus and colostrum production for calcium

• Inc absoprtion of Ca from gut and kidneys

• Mobilise calcium from bones

• Mediated by Parathyriod Hormone and 1,25 hydroxy vitamin D

At what stage in the production year does hypocalcaemia occur in ewes?

Pre-lambing- 6 weeks onwards (most common)

(Not always, can be early lactation)

What are the risks factors for hypocalcaemia?

• Often stress induced

• Other risk factors:

  • Acidosis cereal diet

  • Older ewes

  • Rapid growing lush pasture

What are the clinical signs of hypocalcaemia?

• Initial Weakness and excitement

• Progress to recumbent

• Dilated pupils, constipated, bloated, comatose, death

How can you confirm a hypocalcaemia diagnosis?

• Pre treatment blood sample for Ca

• Response to treatment

What treatment is used for hypocalcaemia?

• Slow IV 40-80ml, 20% (or 20-40ml of 40%) Calcium borogluconate

  • Rapid response

  • Subcut can be given but slower response

• Monitor as may relapse and address risk for rest of flock

What is the typical history associated with hypomagnesaemia/ staggers?

• Post lambing, peak lactation

• Lush rapidly growing grass (can be low in Mg) or bare pastures

What are the clinical signs of staggers?

• Rapid onset, neurological symptoms

• Excitable, tremors, convulsions death

• Found Dead

How is staggers diagnosed?

• History and clinical signs

• Blood sample Mg <0.2mmol/l

How is staggers treated?

• 40-80ml 20% Calcium IV (bc Ca involved in disease process)

• 20-40ml 25% Mg SC (NOT IV)

What are the Ddxs of sick/ recumbant ewe at lambing time?

• Hypocalcaemia

• Pregnancy toxaemia

• Hypomagnesaemia

• Listeria

• Mastitis

• Metritis

• Bloat

• Pasturellosis

• Poisoining

• Acidosis

Summary to compare pregnancy tox, staggers, and hypocal