Enzootic abortion of ewes (EAE) is caused by Chlamydia (Chlamydophila) abortus and is one of the most common abortifacient microbes in sheep. It occurs in all sheep-producing countries and produces late-term abortion.
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.
How is enzootic abortion spread?
Enzootic Abortion is highly contagious from sheep to sheep. 99% of infection takes place around lambing time with ewes and lambs picking the infection up from aborted lambs, infected cleansings and vaginal discharges (which can last for up to 3 weeks) from ewes which have aborted.
How do sheep get toxoplasmosis?
How do ewes get infected? Sheep pick up the toxoplasma parasite readily from the environment by ingesting oocytes (parasite eggs) on pasture or in contaminated feed and water. Cats and members of the cat family are the definitive hosts of the parasite.
How does toxoplasmosis cause abortion in sheep?
Toxoplasmosis as a Cause of Abortion in Sheep
Toxoplasma gondii is a major cause of abortion in small ruminants throughout the world. Ingestion of sporulated coccidian oocytes early in gestation results in resorption or mummification; if ewes contract the disease late in gestation, abortions or perinatal deaths occur.
How do you prevent Campylobacter in sheep?
Azithromycin or ciprofloxacin are commonly used for treatment when antibiotics are necessary (CDC, 2010). Few treatment options are available for infected sheep. Tetracyclines are typically given to exposed ewes during an abortion storm to prevent them from aborting.
What is an enzootic abortion?
Enzootic abortion in sheep and goats is a contagious disease characterized by hyperthermia and late abortion, or birth of stillborn or weak lambs or kids (Rodolakis et al., 1998). The only presenting clinical sign may be serosanguineous vulvar discharges. Other animals may present with arthritis or pneumonia.
What causes enzootic disease?
WHAT CAUSES ENZOOTIC ABORTION? This disease is caused by an organism called Chlamydia psittaci and is one of the biggest causes of abortions and stillbirths in sheep and goats. This organism is found throughout the world, including South Africa.
When do you give Toxovax?
Toxovax is a live vaccine for the active immunisation of susceptible breeding female sheep to reduce the effects of infection by Toxoplasma gondii, namely early embryonic death, barrenness and abortion. A single 2 ml, intramuscular injection is given at least 3 weeks prior to mating.
What is Campylobacter in sheep?
Ovine campylobacteriosis is an infectious disease of breeding ewes causing abortion in late pregnancy. It is caused by the bacteria Campylobacter fetus ssp. fetus. The disease is found in sheep around the world, but is an uncommon diagnosis in Western Australia (WA).
How do you prevent toxoplasmosis in sheep?
There is an effective vaccine to prevent congenital toxoplasmosis in sheep (disease caused by the parasite passing from the dam to the foetus).. Once animals or people become infected with Toxoplasma it is thought that they will remain infected for life with the parasite remaining dormant within tissue cysts.
What are the signs of toxoplasmosis in sheep?
A clinical sign which is characteristic of toxoplasmosis abortion is the development of small white areas in the cotyledons (buttons) of the placenta. These are caused by focal necrosis (death of cells) in areas of the placenta due to damage caused by multiplication of the Toxoplasma organism.
How does T. gondii cause abortion?
gondii enters the bloodstream of the ewe/doe and spreads to other tissues. In pregnant animals, T. gondii can invade and multiply in the placenta and pass to the fetus, causing fetal death, fetal mummification (where the animal reabsorbs the fetal fluid), stillbirth or the birth of weak kids/lambs.
What causes stillbirth in sheep?
Pre-term stillborn: In many flocks, the majority of pre-term losses are associated with abortion diseases. The top three abortion diseases include: Campylobacter, Chlamydia, and Toxoplasmosis. In most flocks, the incidence of pre-term delivery associated with natural causes, non-bacterial, is expected to be 2%-4%.
What causes listeriosis in sheep?
Listeriosis is caused by the bacterium Listeria monocytogenes and is commonly seen in cooler climates. These bacteria can be found in the soil, food sources, and even the feces of healthy animals. Most commonly, this disease of sheep and goats is observed as a result of feeding moldy or spoiled hay or silage.
What is the vaccine for toxoplasmosis?
Given these factors, vaccination has been considered to be the most efficient method to prevent and control this disease. However, there is currently lack of effective vaccine available for use to prevent toxoplasmosis apart form Toxovax®, the only available vaccine, which is used in sheep to prevent abortion.