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Sheuneni Kurasha-Farmer’s Diary
Over the past month, we have received numerous distress calls from farmers across the country who are grappling with a rise in abortion cases within their herds.
For a farmer, abortion represents a double-edged crisis: not only do they lose valuable time and money, but they must also endure the wait for the ewe or doe to go through the mating and gestation cycle again — assuming the mother survives.
In some unfortunate instances, the loss extends beyond the foetus, with the mother also succumbing, compounding the tragedy and the farmer’s hardship.
This week’s instalment explores the complexities of abortion in small ruminants, examining its causes, signs, treatment options, and, more importantly, preventive measures that farmers can implement to ensure the health and sustainability of their livestock.
What is abortion in goats and sheep?
Abortion in goats and sheep refers to the natural or induced expulsion of a foetus before it can survive outside the womb. Unlike a normal birth, where the foetus is carried to full term and is capable of independent life, abortion results in the premature loss of the foetus, often leading to its death.
This distressing event can occur at any stage of pregnancy but is particularly concerning in the later stages when the foetus is nearly fully developed.
What causes abortions?
Several factors can cause abortions in goats and sheep, ranging from environmental stressors to infectious diseases and genetic issues. Understanding these causes is crucial for preventing abortions and ensuring the well-being of the animals.
1. Stress from starvation
One of the most critical and common causes of abortion in goats, particularly those reared on communal pastures, is stress induced by starvation. Pregnant does and ewes require additional protein and energy to support their own health as well as the development of the foetus.
If they do not receive adequate nutrition, their bodies may be unable to sustain the pregnancy, triggering abortion. If the doe or ewe’s diet is insufficient, her body may prioritise its own survival over that of the foetus, leading to abortion.
This becomes even more pronounced during the dry season, that is, from June to November when the pastures become heavily depleted, with the remaining grass offering little to no nutritional value.
The scarcity of sufficient and quality feed creates a highly stressful environment for pregnant animals, thereby significantly increasing the likelihood of abortion.
The situation is often worsened by veld fires, which can devastate vast grazing areas, further restricting the availability of food and compounding the stress experienced by the animals.
2. Infectious and parasitic organisms
Numerous infectious and parasitic organisms can lead to abortions in goats and sheep. Chlamydia and Coxiella particularly pose a significant threat to sheep and goats. Chlamydia is the causative agent of “enzootic abortion”, a severe reproductive disorder that can result in considerable losses within affected herds.
This pathogen is especially disruptive and often causes repeated abortions in infected animals.
Similarly, Coxiella burnetii, another formidable infectious agent, causes Q fever, a disease that not only poses a risk to livestock but also to human health, as it is zoonotic.
This pathogen can lead to abortions in goats and sheep, with the potential for outbreaks to escalate quickly if stringent hygiene and biosecurity measures are not rigorously enforced.
Infections like these often spread rapidly within a herd, particularly in environments where proper sanitation and preventive practices are not in place.
Inbreeding in Angora goats
Inbreeding, particularly in breeds such as Angora goats, can lead to habitual abortions year after year. This genetic problem arises when closely related animals are bred together, increasing the likelihood of inheriting harmful traits that can negatively impact reproductive success.
What signs indicate abortion?
Being able to recognise the signs of abortion in goats and sheep is crucial for timely intervention and effective management. The symptoms can vary depending on the underlying cause of the abortion, and understanding these variations is key to addressing the issue promptly.
1. Abnormal or normal foetus
In some instances, the aborted foetus may appear normal, while in others, it may be abnormal or even decomposed. When abortion is triggered by stress due to starvation, the foetus is often well-developed but delivered prematurely, usually after only 90 days of pregnancy.
In cases of habitual abortions, the foetus may be notably swollen, indicating a different underlying issue.
2. Handling the aborted foetus
If an abortion occurs, it is essential to handle the foetus and placenta (afterbirth) with care. Avoid direct contact, which can spread infections to humans or other animals, it is advisable to wear plastic gloves or use plastic bags when picking them up.
The aborted foetus and placenta should be securely wrapped in plastic and taken to an animal health technician or veterinarian for examination to determine the cause of the abortion.
In addition, it is important to wash your hands thoroughly with soap and water after handling an aborted foetus to minimise the risk of infection.
Treatment options
Treatment for abortions in goats and sheep largely depends on the underlying cause. However, in many cases, treatment is either impractical or economically infeasible.
1. Enzootic abortion
For enzootic abortion caused by Chlamydia, treatment is generally not practical, particularly once the infection has disseminated within a herd. In such situations, preventive measures are far more effective than attempting to treat the infection after it has spread. Implementing vaccination programmes using Enzovax and maintaining rigorous biosecurity practices are crucial in managing this disease. Farmers must remember to store the vaccine between 2°C and 8°C, protect from light and avoid prolonged exposure to high ambient temperatures following withdrawal from the refrigerator prior to use.
Enzovax should also not be handled by pregnant women as the vaccine may cause abortion.
2. Coxiella-induced abortions
Similarly, there is no specific treatment for abortions caused by Coxiella burnetii. Preventive strategies are the most effective approach for controlling the spread of this pathogen. This includes vaccination and the implementation of strict biosecurity measures to reduce the risk of infection within the herd.
3. Starvation-induced abortions
Abortions resulting from starvation cannot be treated once they occur. Instead, they must be prevented through proper nutrition and management practices. It is vital to ensure that pregnant does and ewes receive adequate and high-quality feed throughout their pregnancy, with particular attention during critical periods.
Proper nutritional management is essential to support the health of both the mother and the developing foetus, thereby reducing the risk of abortion.
Prevention strategies
Preventing abortions in goats and sheep requires a proactive approach, concentrating on nutrition, disease control, and genetic management. Ensuring that pregnant does receive sufficient high-quality food is essential to prevent abortions caused by starvation.
The most critical periods for nutritional support are the last two months of pregnancy and the first two months after giving birth. During these four months, does and ewes need additional feed to meet their increased nutritional demands.
For a grazing doe or ewe weighing around 40 kg, daily requirements include about 530g of energy-rich feed such as molasses, maize, barley and wheat bran, along with about 530g of protein-rich feed from sources like soya cake and sunflower cake. In addition, 10g each of salt and mineral mix are necessary to ensure a balanced diet.
Effective disease prevention is crucial for avoiding abortions caused by infectious agents. Consistent vaccination with Enzovax is important to protect against enzootic abortion. For abortions induced by Coxiella burnetii, regular dipping is critical to ensure control of tick populations since ticks are the primary vectors for this pathogen.
Implementing rigorous disease control measures and maintaining proper hygiene can further reduce the risk of infection.
Genetic management also plays a key role in preventing habitual abortions, particularly in breeds like Angora goats where inbreeding can be a problem. In such cases, farmers must avoid mating closely related animals and introduce genetic diversity into the herd. Focusing on these three areas —nutrition, disease prevention, and genetic management — farmers can effectively reduce the incidence of abortions.
Conclusion
Abortion in goats and sheep is a multifaceted issue that demands a comprehensive approach for effective management. Although treatment options are often limited, particularly for abortions caused by infections and genetic factors, prevention through proper nutrition, disease control, and breeding management can significantly reduce the incidence of abortions in small ruminant herds.
Sheuneni Kurasha is the managing director of Chivara Farm, a diversified farming operation, which specialises in stud breeding for small livestock (Boer goats, Kalahari Red goats. WhatsApp: +263 77 2874 523.
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