The last eight weeks of pregnancy are incredibly important for your ewe. This is the time to check for three of the most common peri-natal conditions to help avoid lamb losses. Once you know what to look for it’s possible to protect ewes and be of greater assistance to them.
70% of foetal growth occurs in the last eight weeks of pregnancy. Nutrition is vital to ensure lambs are healthy and do not have too high or low a birth weight, improving survival. Equally, colostrum is formed at this time; the ewe must produce the required levels needed to satisfy her young after birth.
Prolapses in Ewes Most common: Last 8 weeks of pregnancy
A prolapse can damage the birth canal, leading to a difficult lambing. There are several potential causes of a prolapse, however, those carrying multiple litters are most susceptible and around 1% of all ewes suffer.
Signs of a vaginal prolapse
Be it diet or handling, there are many causes that can result in prolapse:
- Hypocalcaemia (calcium deficiency)
- Excess fibre in the diet
- Inadequate exercise
- Standing or lying on steep slopes
Sheep can also be predisposed to this problem or have a hormone imbalance.
In severe cases, an epidural and the help of a vet is required to return the prolapse. Sutures are usually required, although some farms use a restraining harness. Any ewe that has prolapsed should be culled for she is at risk of having a prolapse again the next year.
Tip: Ensure the correct feeding of ewes in late pregnancy because this can cause prolapse.
1. Pregnancy toxaemia (or Twin Lamb Disease)
Most common: Last 4-6 weeks of pregnancy
This metabolic disorder generally affects ewes with a low or high Body Condition Score (BCS). Additionally, those carrying multiple lambs are at highest risk.
- Ewe becomes depressed
- Isolates herself
- Won’t eat
- Adopts wide-based stance
- Loses reflexes
- Stretches neck back (known as ‘stargazing’)
- Grinds teeth
- Presses her head against things
Pregnancy toxaemia is caused by a lack of energy intake and low blood glucose levels.
Affected ewes must be separated and not fed with the rest of the group.
To treat the condition, you need to replenish glucose levels by giving an injection of glucose or utilising a slow release drench such as propylene glycol. Importantly you must also correct the feeding of the ewes.
Tip: Monitor the ewes throughout pregnancy to check they’re on target for a healthy BCS.
2. Hypocalcaemia (or Milk Fever)
Most common: Last 4 weeks of pregnancy
As pregnancy progresses lambs have an increasingly high demand for calcium, obtained through milk and through the placenta. The ewe’s diet must be nutritious enough to provide for this. Otherwise, she can develop hypocalcaemia, a serious metabolic disorder. If left untreated, sheep may then eventually become comatose and die.
Ewes become unsteady and lie down. If a number of ewes are affected in this way, the first thing to check and correct is the diet.
Replenish calcium levels, this can be done by calcium injection.
Tip: For every pregnancy, good nutrition is vital to help avoid complications.
For further information contact your veterinary surgeon, advisor or Zoetis UK Limited, Walton Oaks, Dorking Road, Tadworth, Surrey KT20 7NS. www.zoetis.co.uk. Customer Support: 0845 300 8034. Use medicines responsibly (www.noah.co.uk/responsible). Date of preparation: December 2016.