Tannins could be future solution to controlling internal parasites
Tannins could be used to treat of intestinal parasites in sheep in the future, particularly since the prevalence of resistance to conventional anthelmintics in increasing. Some good news for sheep producers, which was shared with delegates at this year’s British Society of Animal Science annual conference by Dickon Hovell from the University of Aberdeen. The finding was the result of a study carried out to determine the effectiveness of quebracho tannins as an alternative to anthelmintics in the control of gastrointestinal nematode parasites in lambs.
“Since their development, sheep producers have become heavily reliant on anthelmintics for the effective control of nematode parasites in their lambs and other grazing livestock. However, alternative approaches in the control of nematode parasites now need to be found due to the increasingly widespread development of anthelmintic resistance,” he said, explaining the rational behind his work.
Forty cross-bred store lambs were brought inside one week before the experiment, ranked according to live weight, allocated to replicates of eight animals according to ranking, and to one of five treatments within each replicate at random. Faecal samples were collected and faecal egg counts (FEC) made. The lambs were housed in groups of eight, bedded on straw, offered an ad-lib diet of hay and 1.2kg of sugar beet pulp per group twice daily with continuous access to clean fresh water.
On day one, lambs in groups one and two were dosed with 30g of quebracho tannin, and lambs in group three with 60g quebracho tannin. Lambs in group four were dosed with 8ml of a conventional anthelmintic wormer. Lambs in group five were un-dosed controls. On day three of the experiment lambs in group two were dosed again with 30g of quebracho tannin. Lambs were weighed weekly, FEC were made twice weekly on six lambs from each group. The effect of treatment on FEC was analysed at each separate sampling time.
“As expected, the control group had the highest FEC and lambs dosed with the conventional anthelmintic wormer had a lower FEC than the control, with those dosed with quebracho tannins giving intermediate egg counts,” said Dr Hovell.
“Although not significant statistically, treatment with the conventional anthelmintic wormer gave the best weight gain of 2.0kg and there was the suggestion of a response to the tannin.
“Further work needs to be carried out on the dose level and dosing regimens with the use of quebracho tannins in commercial situations,” he added.
Presented to the British Society of Animal Science Annual Meeting, March 31 to April 2, 2008, Scarborough, UK.
Full details: Cruden L and Hovell FDdeB: “An evaluation of quebracho (Schinopsis quebracho-colorado) tannin for the treatment of sheep gastrointestinal parasites.”
summary (pdf) Presentation_096cruden (pdf)
For further information visit http://www.bsas.org.uk/Publications/Annual_Conference_Proceedings/or contact BSAS on 0131 445 4508 or bsas@sac.ac.uk
