Common health issues around lambing time and the important role nutrition plays in having a successful lambing season was highlighted at the National Sheep Conference this week.
Speaking on the topic was Professor Neil Sargison of the University of Edinburgh. He said: “Ewes must already be in correct plane of nutrition as they enter the final 6 to 8 weeks of pregnancy. He noted: “If your ewes are not in target body condition score this can lead to catastrophic consequences in terms of animal health.
Sargison outlined some of the common health problems on sheep farms at lambing:
Grain overload
Sargison outlined that grain overload is caused by rapid increases in the level of concentrate feeding. He said this leads to rumen fermentation rather than digestion. This in turn causes lactic acid production and acidosis and endotoxic shock.
For farmers he highlighted that clinical signs of grain overload include; mild colic and tooth grinding, staggering gait, apparent blindness, scour, stupor, collapse or laminitis during recovery.
Hypocalcaemia
Sargison noted that hypocalcaemia is very common. He said it occurs from six weeks before lambing and ewes respond to treatment.
He outlined when this occurs ewes are unable to absorb sufficient calcium from the diet for the requirements of pregnancy and colostrum accumulation in the udder. This leads to a dependence on skeletal reserves.
He noted Hypocalcaemia is a clinical disease when absorption and resorption are insufficient. It can be caused by stressful husbandry, transport or weather. Older ewes are at risk with depleted skeletal reserves following previous pregnancies and lactations. Ewes on cereal based diets low in calcium are also prone to Hypocalcaemia.
Vaginal prolapse
Vaginal prolapse is a common problem on sheep farmers around lambing. A flock incidence of 1% is normal. The problem is usually caused by a range of issues such as Inflammation, swelling, trauma, infection and urinary retention. Sever cases can lead to death.
Ewes at risk are those with multiple foetuses, eating bulky feed, have excessive body condition, high fibre diets, rumen acidosis, lack of exercise, subclinical hypocalcaemia, steep slopes of farmland or short docked tails.
Management of Vaginal prolapse is successful. Both plastic spoons and harnesses do work. However he noted often surgery is needed.
Pregnancy toxaemia (twin lamb disease)
Sargison highlighted that twin lamb disease is a common disease of undernourished, stressed ewes carrying multiple foetuses. It is caused by a failure to adapt to increasing metabolic demands of late pregnancy.
For farmers clinical signs of twin lamb disease include depression, apparent blindness, salivation and fine muscle tremours. He noted Treatment of ovine pregnancy toxaemia is often uneconomic and unsuccessful. He stressed its occurrence usually indicates an urgent need to increase the energy nutrition of the rest of the flock.
Mastitis
Sargison cited that mastitis can also be common on sheep farms at lambing time. He said it is caused by inadequate milk supply, exposer to the cold or in some cases orf.
He noted that treatment of mastitis is with macrolide antibiotics and anti‐inflammatory drugs, or in severe cases humane destruction is necessary.
Sargison stressed that farmers should focus on prevention noting that correct nutritional and disease management throughout the ewe’s production cycle is key.
