On the sick list
All animals can get sick from time to time, but there are certain disorders that are only encountered during pregnancy or lactation. In particular, there are infections that can result in abortion, metabolic disorders that may be brought about by nutritional stress and other complications, such as mastitis (inflammation of the udder), prolapse and difficulties encountered during the actual birth process.
An abortion (‘miscarriage’) may be caused by rough handling or other stressful situations, or by an infectious agent. Abortions may pass unnoticed, unless they occur during the final third of pregnancy. Depending on the cause, affected animals do not always appear unwell.
The safest option, if an animal is seen to have aborted, is to assume that it may be infectious and to isolate her from the rest of the flock or herd. Your vet can take a blood sample and collect foetal material for analysis in order to determine the cause. Consider using a vaccine against the commoner forms of abortion in future.
TIP: Be aware that some forms of abortion in livestock are zoonotic and pose a very serious risk to pregnant women.
TIP: In the case of toxoplasmosis, which is a common cause of abortion in sheep, domestic cats are the principle source of infection. Toxoplasmosis can also affect other mammals, including humans. Young cats and breeding females are the worst offenders, so reduce the risk by only keeping neutered adult males on the holding. Also try to prevent cats from soiling stored livestock feed and forage.
In terms of metabolic disorders, I am primarily talking about pregnancy toxaemia, hypocalcaemia and hypomagnesaemia, all three of which are closely linked to nutrition and stress. The
first two are most likely to be encountered in late gestation, with hypomagnesaemia being seen in early lactation in grazing livestock, and also sometimes in the autumn. The symptoms of pregnancy toxaemia and hypocalcaemia are very similar, but whereas hypocalcaemic animals respond very quickly to treatment, which consists of injections of calcium borogluconate, which is something any smallholder can carry out themselves, animals suffering from pregnancy toxaemia do not, and a high proportion will die despite careful nursing. Hypomagnesaemia is best avoided by providing supplementary magnesium, in the form of licks or boluses, during periods of high risk.
Any pregnant animal that appears lethargic, reluctant to feed or which separates itself from the rest of the flock or herd is likely to be suffering from one or other of these disorders and must be treated immediately. Don’t wait to see if it is a bit better in the morning — it won’t be. The first course of action is to inject calcium borogluconate and observe the response. If it subsequently turns out to have been suffering from something else then your initial treatment won’t have done any harm and will have helped to combat stress.
TIP: When they go down, ewes suffering from hypocalcaemia (calcium deficiency) look like they have toppled over forwards, whereas those suffering from pregnancy toxaemia (twin lamb disease) appear to have slumped backwards.
Hypocalcaemia: simple to cure, but fatal if not treated quickly. Would you recognise the symptoms in time?