Assess nutrition and health status by blood-testing ewes

Information obtained from blood-testing of ewes can give a useful insight into the nutrition and health status of a flock, according to Scottish veterinary practitioner Andrew Robinson.

Metabolic profiles are commonly taken on pooled blood samples and to test for trace element levels. However, speaking at the annual general meeting of the National Sheep Association’s (NSA) NI branch on Monday evening, Robinson encouraged farmers to also test for protein and ketone levels.

Testing for levels of the ketone BHB, three weeks before lambing, gives an indication of a negative energy balance and the potential risk of twin-lamb disease arising, Robinson said at the event at AFBI Hillsborough.

He said that testing for urea nitrogen shows if dietary protein intake is sufficient and testing for levels of the blood protein albumin shows the longer-term blood protein status of ewes. Low albumin levels in sheep often point to underlying issues with livers caused by chronic liver fluke.

Tests that cover BHB, urea and albumin, as well as trace elements, cost around £30 per ewe. Robinson recommended testing several ewes that are scanned for one, two and three lambs about three weeks before lambing so that remedial action can be taken in time.

Also speaking at the NSA event, Dr John Robinson from Scotland’s Rural University College pointed out that blood mineral levels around lambing time were important for the development of eggs for the next year’s lamb crop.

“Follicles develop into the eggs that are released from the ovary at breeding time. But follicular development initially begins four to six months before a ewe ovulates, so the process really starts shortly after she lambs the previous season,” Dr Robinson said.

On the importance of cobalt deficiency, he said that sheep farmers in areas that are deficient in cobalt often supplement lambs around weaning time, but he emphasised that adequate cobalt levels were also important in ewes at tupping.

To illustrate the point, he quoted results from an experiment in Scotland, where lambs that were conceived in cobalt deficient ewes, were embryo-transferred after six days to surrogate ewes with optimal cobalt blood levels. These lambs were less active at birth than lambs that had been conceived in ewes with adequate cobalt levels.

Jamieson elected NSA NI branch chair

Ballycastle sheep farmer Brian Jamieson was elected chair of the NSA’s NI branch at the organisation’s AGM at AFBI Hillsborough on Monday evening. He replaces Campbell Tweed from Cairncastle who has served a two-year term as chair.

Jonny Farmer from Portglenone replaced Jamieson as vice-chair of the NSA’s NI branch.

Representatives from the NI branch that will sit on UK-wide NSA committees include John Blaney from Cushendun who will sit on the board of trustees, Brian Jamieson on the finance committee and Campbell Tweed on the policy committee.