Only 26 per cent of flocks vaccinated against toxoplasmosis in 2024.

Research from the Agriculture and Horticulture Development Board (AHDB) has highlighted opportunity for farmers to increase abortion control in flocks.

The data reveals that, while uptake had already reached 50 per cent for enzootic vaccines, just 26 per cent of flocks were vaccinated against toxoplasmosis.

Although the sector has struggled with vaccine availability in the past, the board believes there is opportunity for greater protection in the national flock. Enzootic abortion and toxoplasmosis are identified by the Animal and Plant Health Agency as two of the most common causes of sheep abortion in Great Britain.

MSD Animal Health’s FlockCheck programme collected diagnostic data from 400 sheep flocks in 2025.

This data revealed that 79 per cent of flocks had been exposed to Toxoplasma gondii. Meanwhile, 35 per cent of flocks had been exposed to Chlamydia abortus, the bacterium which causes enzootic abortion.

Enzootic abortion is highly contagious, occurring primarily through feed contaminated with cat faeces. Infected ewes will show no signs until late pregnancy and can become lifetime carriers.

Since parasite eggs can survive for over a year, vaccination is considered the most reliable form of protection.

MSD Animal Health says that their results support farmers in making targeted vaccination decisions. This helps them safeguard flocks and maximise lambing outcomes.

Where abortion rates are exceeding two per cent, or scanning results prove lower than expected, farmers can get practical support through the subsidised FlockCheck scheme. The scheme, available through veterinary practices until 30 June 2026, provides blood testing for six to eight aborted or unvaccinated ewes, or for barren ewes and those producing weak lambs.

The tests will help farmers to recognise the underlying causes of abortions, as well as informing the value of a pre-tupping vaccination programme.

Dr Kat Baxter-Smith, MSD veterinary advisor, said: “If results highlight an issue with either disease, both can be controlled effectively through a simple vaccination programme,

“Abortion diseases like enzootic abortion and toxoplasmosis often remain hidden until significant losses occur. Once established, they are extremely difficult and costly to manage, making prevention through vaccination vital.”

Image © Serenity Images23/Shutterstock.com