Understanding illness key to preventing flock loss
Published:  20 October, 2016

Sheep producers have been told that using stock data from fallen animals can help stop further loss. 

These findings come as part of a two-year project funded by the Agriculture & Horticulture Development Board (AHDB) Beef & Lamb. The initiative looked into the impact of using post-mortem (PM) examinations to make meaningful diagnosis and communicating the results to producers in an efficient timescale.

A total of 472 adult sheep carcases were examined during the project, 455 of which were ewes, and 101 different causes of death were found for the animals.

8.4% of the carcases were diagnosed with ovine pulmonary adecarcinoma (OPA), which is consistent with previous estimates of incidence from examining fallen stock. These results came from 22 farms, seven of which reported multiple cases. The illness can lead to difficulty in breathing and dramatic weight loss.

Johne’s disease was also a prominent cause of death. As it can present itself in multiple forms, the illness can often be difficult for PM technicians to diagnose. An easy way to do so is the yellowing of the gut. Johne’s disease was found in 6.8% of submissions from 25 farms, with five submitting multiple cases. Similar to OPA, Johne’s presents itself with dramatic weight loss and can be picked up on when assessing body condition. The early culling of affected animals will help limit further animals from falling sick.

During the first year of the project, listeriosis was diagnosed in 14 adult ewes, and 16 in the second year. Cases were clustered during autumn and winter during 2015/2016, a very wet and muddy period of the year. Any variety of soil contact, including muddy feed troughs, molehills and bare, poached patches on pasture all pose a risk. AHDB recommends that efforts should be made to limit soil contamination of feed troughs and employing “ruthless” mole control.

Ewes are also at risk from infection when they are fed forage that has not been conserved or stored well and can become an issue when the animals are brought in over the winter months. Producers are also advised to ensure silage is stored correctly and protected from vermin, while spoiled silage should be discarded.