Pregnancy Toxaemia, Ketosis
or twin lamb or twin kid disease

This condition is also known as ketosis or twin lamb or twin kid disease, or gestational toxaemia. The problem occurs during late pregnancy, particularly in animals that are carrying twins. The condition arises due to inadequate nutrition at the time when the growth of the foetus is occurring rapidly. The ewe or doe collapses into a coma and dies. Treatment involves injecting or drenching the animal with a source of glucose.

Symptoms Control Measures References and Further Reading

Pregnancy Toxaemia is a metabolic disorder characterized by an abnormal decrease of sugar levels in the blood (hypoglycaemia) and by hyperketonaemia (an excess of ketone bodies in the blood, as in starvation and diabetes). This results from an inability of the animal to maintain an adequate energy balance.

The symptoms include neurological problems and weakness. In general, the problem develops in the last third of pregnancy or in the 2-3 weeks before giving birth, with a greater incidence in animals with twins. The problem can also be observed in poorly nourished sheep with only a single foetus. In susceptible animals, toxaemia may appear in the last six weeks of pregnancy when the foetuses have reached two thirds of their development. The affected sheep appear apathetic, clumsy and depressed, and tend to separate from the rest of the herd and remain immobile. Following this the animals fail to respond to external stimuli, have difficulty walking and do not eat or drink.

The cause of toxaemia is an alteration in energy metabolism as a consequence of an imbalance between glucose supply and demand. This results in a negative energy balance, and is caused by a reduction in energy supply due to poor or inadequate nutrition, deficient food absorption, or an incorrect metabolic use of the food ingested. To this must be added the increasing requirements of the foetus in its later stages of growth and the physical pressure of the increasingly large and heavy uterus on the digestive organs - the rumen, intestines, liver, etc.

Contributing factors may include:

• A lack of food towards the end of the gestational period.
• Imbalanced fodder rations, or poorly preserved fodder.
• Stress - resulting in increased energy expenditure or a decrease in food consumption.
• Poor weather conditions (heat, rain etc) without adequate protection for the animals.
• Poor dentition or worn teeth (usually age related).

 

In general terms, the response to treatment is irregular, and in many cases poor. Success depends on the early detection of the problem and a prompt normalization of the appetite and adequate food intake of the affected animal.

Treatment involves injecting or drenching the animal with a source of glucose. In addition, providing attractive food materials in an attempt to a regain a normalization of appetite, digestion and ruminal processes is also required.

The best approach for avoiding development of the toxaemia is to feed the animals correctly - particularly in the later stages of pregnancy. It is essential to ensure early control of the condition in animals during this period, with the prompt detection and correction of any possible problems. One solution is to divide the animals into three batches according to their body status (fat, normal and thin) by use of condition scoring. This then makes it easier to supply an adequate diet with different amounts of supplemental feeding according the the individual requirements.

For more on Condition Scoring

Pastor, J., Loste, A. and Sáez, T. (2001). Gestational toxemia in sheep. Pequeños Rumiantes, Vol. 2, No. 3, pp. 18-24.