Effects of abortion in goat and sheep production
Farmers get frustrated to lose the production of livestock due to abortion.
While they expect so much from a pregnant animal, and even predict the number of calves or lambs that will be born that season.
These days, most farmers especially in Omaheke region (Aminius and Epukiro) complain about the loss of production in goats and sheep due to enzootic ovine abortion (enzootiese aborsie in Afrikaans).
Enzootic is the most common causes of abortion in goats and sheep caused by an infection of the uterus by Chlamydia abortus bacteria, hence the common name chlamydiosis.
The word enzootic describes that the disease is restricted to a locality or a population of animals that picks up the infections. It must always be considered when you have an abortion epidemic (lots of abortion cases in your kraal).
Animals tend to be infected after they have ingested infected aborted materials such as the placenta or dead foetus membranes.
Sometimes, the bacteria are also passed in the faeces of an infected ewe. There is also a suspicion that enzootic abortion can be transmitted by ticks, rodents (mice/rats) and birds rather than sexual contact with rams.
What is scary about chlamydiosis of goats and sheep is that the disease is a zoonosis (transmitted from animals to people) and the contaminated materials must be handled with biosafety precautions. Pregnant women are particularly at risk when handling aborted foetus and afterbirth.
The disease is characterised by premature delivery or abortion (still born) within the last month of pregnancy, although most commonly it is exactly 3 weeks ahead of the scheduled time. Sometimes, if not aborted, the lambs come out extremely weak and die shortly. Sometimes the doe also die after, especially, if the dead foetus was carried inside the doe for a length of time. One strange thing is that in multiple births such as in twins, one lamb can be born normal while the other is infected and stillborn.
The good news is that those ewes that have aborted rarely do so again and will usually breed successfully the following year and deliver with no difficulty. However, the bad news is that for those that are infected very late in pregnancy, they may deliver normally this time and then abort next year.
What to do about abortions:
Isolate any animal that have aborted in a separate kraal especially away from other pregnant ones. You can also remove pregnant animals to another clean place as there may be infection on the ground where the abortion was.
You have to burn or bury all aborted foetus together with the placenta
Cleaning and disinfecting the area is highly important. And always wear gloves and protective clothing when handling such cases and wash yourself after.
One animal aborting might not be a crisis but if there are more than one, treat the sick animals and those that have been in contact with them:
The treatment of using long acting tetracycline(e.g. Terramycin ®, Swamycin ®) or trimethoprim sulpha drugs (e.g. Disulfox® or Norotrim®) on all does (even the pregnant ones) and surviving kids might be helpful. Inject the exposed ewes and does 6 and 3 weeks apart before lambing. One can also inject the pregnant animals with multiminerals especially that contains selenium and copper, a month before giving birth to help balancing the nutrients in the body. Hopefully by now, you have also given Vitamin A at the start of the dry season to help with the reproduction.
There is a vaccine (like Chlamysure® or Onderstepoort Enzootic Abortion vaccine ®, EnzoVaX ®) available from your veterinary medicine suppliers which may be helpful. This vaccine is given before animals are mated and not while pregnant. Thus, to make sure that the animals you are vaccinating are not pregnant yet, you can give the vaccine after month of giving
For proper treatment and control of abortion in a flock, a diagnosis of the cause of abortion is important. Thus, it is imperative for our farmers to take a sample for the laboratory. You can wrap aborted foetus and or after birth in a waterproof plastic container or glass even in those mayonnaise bottles and keep it cold in the fridge or keep in a cool place, but do not freeze. This can be taken to your nearest veterinary office or straight to the Central Veterinary Laboratory in Windhoek.
Enzootic abortion can cause serious economic loss to your small stock production and should be treated with the utmost consideration and planning. The bottom line is, there is a vaccine available for this disease and farmers should treat all pregnant animals with an antibiotic when exposed