Non-infectious causes of abortion include rough handling, fighting among animals, inadequate nutrition, and plant poisons. Ewes infected with Vibrio typically abort during the last 6-8 weeks of pregnancy or give birth to weak or dead lambs. Once a ewe aborts, she is immune to the disease.
What causes sheep to miscarry?
The major infectious agents causing abortions in sheep are Campylobacter sp, Chlamydia sp, Toxoplasma sp, Listeria sp, Brucella sp, Salmonella sp, border disease virus, and Cache Valley virus.
What are the two major causes of abortion in sheep?
Toxoplasmosis and enzootic abortion (EAE) are the two most common causes of sheep abortion that are diagnosed from post-mortem submissions by the Animal Plant and Health Agency (APHA) (Figure 1). Sheep abortion results in considerable economic loss to the flock and increases stress during lambing.
What causes stillbirth in sheep?
Abortions and stillborn lambs are usually caused by an infection like toxoplasmosis, vibriosis, chlamy diosis or leptospirosis. Lambs may also be born weak and die shortly after birth as a result of these infec tions. Infections are often a result of poor farm hygiene or poor biosecurity.
How do you prevent toxoplasmosis in sheep?
You may wish to consider vaccinating older ewes if they are bought in from a different flock as naive drafts. Breeding female sheep should all be vaccinated between four months and three weeks before tupping. Ewe lambs must be aged over five months for their first vaccination before tupping.
How do sheep increase fertility?
- the use of teasers and the ‘ram effect.’
- short term flushing with a high energy diet.
- use of products such as ‘Ovastim’ to increase ovulation rates.
- use of melatonin containing products which ‘trick’ the animal’s reproductive system into thinking the days are shorter which triggers ewes to cycle.
When do sheep abort?
Once infected a ewe/lamb will carry the infection until she next becomes pregnant and will then abort, usually in the last 2-3 weeks of pregnancy. Ewes aborting this year were probably infected at lambing time last year.
What causes bluetongue?
What is bluetongue and what causes it? Bluetongue is a non-contagious, viral disease spread by biting insects. It affects species of ruminants, particularly sheep.
What does a sheep abortion look like?
Infection typically results in the abortion/birth of fresh dead and/or weak lambs during the last three weeks of gestation. The ewe is not sick and may only be identified by a red/brown vulval discharge staining the wool around the tail/perineum, and a drawn-up abdomen.
What is sheep Chlamydiosis?
Chlamydiosis is a highly contagious infection that commonly occurs in sheep flocks of the western U.S. However, because laboratory confirmation of chlamydial abortion can be difficult, the true incidence is not easy to quantify and many infections are not reported.
What is milk fever in sheep?
Milk fever may also occur around lambing, as the ewe’s hormones may inhibit her ability to sufficiently mobilize calcium reserves. The symptoms of milk fever and ketosis are similar, though milk fever seems to develop more suddenly. The differential diagnosis is the ewe’s response to calcium therapy.
What is Vibriosis in sheep?
Vibriosis (Bovine Venereal Campylobacteriosis, BVC) is a world-wide disease which causes early embryonic death and infertility in cattle. The same gram negative rod bacteria causes abortion in sheep. This infection is economically important because it causes a large decrease in reproductive efficiency.