As we are rapidly approaching lambing here is a reminder of what to look out for in ewes. The main risk is when ewes are off feed for any reason such as pre-lamb treatments or if pre-lamb shearing has been delayed due to bad weather. Sleepy sickness (pregnancy toxaemia)  Cause: Low energy levels due to high demands of pregnancy not being met by feed supply, especially in older ewes with multiples. Effect: Ewes become “sleepy”, slow, stagger, and muscles of the head twitch. The signs progess to ewes sitting down, going into a coma and dying.

Treatment: Extra energy. Either as a drench such as ketol, or injectable metabolics such as Calpromax which are given under the skin. Treatment is usually ineffective in sheep that are down due to kidney failure. Prevention: Energy drench such as Ketol to twin/triplet ewes when yarded close to lambing. Ensure feed supply meets ewe demand. In most cases we can’t change the feed on hand now, but a plan can be made for next season. Milk fever (hypocalcaemia) Cause: Low blood calcium due to high demands of pregnancy and lactation. This can be caused by low calcium in feed and also low bone reserves of calcium in older ewes, especially following a drought. Often due to a sudden change of feed, or holding in the yards for pre-lamb treatments. 

Effect: Ewes stagger, become weak, sit down, bloat and have head turned into their flank. Within 24 hours the ewe goes into a coma and dies. Treatment: Calcium injected under the skin such as Calpromax (100ml/ewe). Response occurs within 15-30mins with the ewe getting up and eating. If no response it is likely that sleepy sickness is also present.

Prevention: Keep pre-lamb mustering and yarding times as short as possible. If changing feeds during pregnancy do it over 2-3 weeks. Issues have occurred in mobs of ewes being fed plantain (high in calcium) pre-lamb and then set-stocked onto pasture (low calcium). Often low energy and low calcium happen at the same time. Low magnesium can be a factor too. Have some combination metabolic products like Calpromax for injection and Ketol for follow up drenching on hand, especially when yarding ewes for pre-lamb treatments.

If you notice problems let your vet know as treatment can be effective, and collecting some samples (even from dead ewes) to identify the cause helps to develop a plan to prevent losses for the next season.

09 July 2018, 03:50