WORMS MAY BE REASON FOR LOSSES OF LAMBS

Press, Volume XCVII, Issue 28491, 22 January 1958, Page 13

WORMS MAY BE REASON FOR LOSSES OF LAMBS

A consistent feature of all postmortem examinations made of lambs which have died in a suspected outbreak of ill-thrift in about 30 to 40 square miles of country between Morven, Glenavy and Ikawai has been a heavy infestation of small stomach worms. Mr M. C. Armstrong, Government veterinarian in South Canterbury, said at the week-end that he had tentatively identified the worm as a species of ostertagia. The reason for the incidence of the worms is being investigated. About 15 farms have been affected by the trouble. They are all on light land and are situated near the coast. In the Glenavy-Morven area especially, many of the farms are adjacent to one another. Losses of up to 100 lambs have been recorded. On 12 farms representative of the outbreak, veterinary investigations have been made by Messrs Armstrong and H. J. Elgie, livestock instructor of the Department of Agriculture, at Waimate.

Post-mortem examinations have been made of affected lambs on all of the 12 farms and specimens have been submitted to the Wallaceville veterinary laboratory. Mr Armstrong said that all of the farms were on country where drenching against parasites had not been customary in past years. The area had a history of being excellent sheep country and lambs had fattened on it very well. This year, however, with adverse conditions —long periods of wet cold weather —it rather looked as though the elements had favoured the incidence of a small stomach worm .which had defied the worm control measures which had been adopted this season by local farmers. Farmers who had unthrifty lambs were being advised to give them large doses of very fine

particle Phenothiazine in an attempt to destroy the small stomach worm. Not Consistent

Mr Armstrong said that an investigation was being made of any other reason, apart from climate, which might be responsible for the unthriftiness. It had occurred on a variety of feed stuffs including lucerne, clover and hay aftermath. “The feed story does not appear to be consistent,” he said. There was, however, one underlying feature —the lambs had evidently suffered a check sometime early in November and the trouble had become apparent since then.

With the cold wet conditions there has been an unusual growth of clovers in pasture. On some ; farms the red and white clover ; growth has been phenomenal. There was still a bad tail-end of lambs on quite a number of far ns, said Mr Armstrong, but on these same farms a few drafts of lambs had been fattened and sent off to the works. It appeared as though the later-born lambs were affected. The earlier lambs had fattened quite well. On several farms in the affected area cobalt trials will be made. Mr Armstrong said that this was being done not because they believed that cobalt was behind the present trouble but rather to eliminate the posisbility of there being such a deficiency. In addition to the veterinary investigations, a team from the econpmic section of the extension division of the Department of Agriculture in Christchurch under the. direction of Mr R. C. Stuart was engaged on a fact-finding survey to, ascertain the facts on the various farms. These would be all collated and analysed as had been done , last year in the outbreak in Mid-Canterbury. This work was still proceeding, he said.