Progress 07/07/04 to 09/30/05
Outputs
The goal of this research effort was to establish alternative methods to manage gastrointestinal nematode parasitism other than reliance on anthelmintics in small ruminants. The specific objective of this proposal is to evaluate an integrated approach using smart drenching, moxidectin, copper-oxide wire particles (COWP) and the FAMACHA System. This project evaluated the field application of 3 scenarios for controlling nematode infection in weaned lambs (Trial 1) and goat kids (Trial 2). There were 3 treatment groups per trial. 46 lambs were allocated to 3 groups (Groups 1, 2 and 3) of 15, 16 and 15 animals. 30 kids were allocated to 3 groups (Groups 1, 2 and 3) of 10 animals each. Group 1 served as a control where all animals were dewormed at 4 week intervals with levamisole. Group 2 used the FAMACHA system where individual animals were dewormed with moxidectin when scored as needing deworming using the FAMACHA eye color chart (score of 4-5 for lambs and 3-5 for kids).
Group 3 integrated the use of moxidectin, smart drenching, COWP and FAMACHA. All animals were dewormed initially with moxidectin. When infection level increased, all animals were given 2 grams of COWP. FAMACHA monitoring was used during periods between treatments to identify individual animals that needed deworming (combination of albendazole and levamisole - smart drenching). Trial 1 was conducted for 16 weeks and Trial 2 for 20 weeks. FEC and blood PCV indicated that the three treatment scenarios adequately controlled nematode infection in both trials. However, Group 2 tended to have a higher FEC and lower PCV than Groups 1 and 3. For both trials weight gains were not significant between groups. For Trial 1, Group 1 received 75 levamisole treatments, Group 2 received 29 moxidectin treatments and Group 3 received 15 moxidectin, 30 COWP and 9 levamisole/albendazole treatments. For Trial 2, Group 1 received 60 levamisole treatments, Group 2 received 20 moxidectin treatments and Group 3
received 10 moxidectin, 10 COWP and 16 levamisole/albendazole treatments. For Trial 1, the cost of anthelmintics/COWP per animal for Groups 1, 2 and 3 were $0.75, $0.33 and $0.55. For Trial 2, the cost of anthelmintics/COWP per animal for Groups 1, 2 and 3 were $0.90, $0.36 and $0.90. For both trials, Group 3 received 31 (62%) and 34 (57%) fewer anthelmintics treatments and the Group 2 cost was the least, but required 2-3 times more labor. However, Group 2 lambs and kids received 21 (42%) and 40 (67%) fewer anthelmintic treatments than Group 1. Thus, both Groups 2 and 3 substantially reduced exposure of the nematode population to anthelmintics while achieving relatively similar results. The mean efficacy of levamisole (Group 1) for Trials 1 and 2 were 83.3% and 86.2%. Efficacy of the moxidectin and the COWP treatments for Trial 1 was 93.5, 97.1 and 96.3%. Efficacy of the moxidectin and the COWP treatments for Trial 2 was and 98.2 and 91.5%.
Impacts
Both treatment scenarios adequately controlled infection level. Groups 2 and 3 substantially reduced exposure of the nematode population to anthelmintics. Because Group 2 was more labor intensive, economically speaking it might not be reasonable to rely on using the FAMACHA system alone for control. The integrated approach of Group 3 (one anthelmintic and COWP treatment(s) to all animals with individual anthelmintic treatments based on FAMACHA) appears to be a viable alternative. The high efficacy of moxidectin and COWP indicates that these could be useful in integrated control programs; however, the use of COWP should be used with caution in sheep due to potential toxicity. FAMACHA is only useful where H. contortus occurs.
Publications
- Miller, J., Burke, J., Olcott, D., Olcott, B., 2005. Integrated approach for controlling nematode parasites in lambs and kids. Proc 20th Inter Conf World Assoc Adv Vet Parasitol: 285.
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Progress 01/01/04 to 12/31/04
Outputs
The goal of this research effort is to establish alternative methods to manage gastrointestinal nematode (worm) parasitism other than reliance on anthelmintics, specifically where Haemonchus contortus is predominant, in small ruminants. The specific objective of this proposal is to evaluate an integrated approach to control worms using smart drenching, moxidectin (Cydectinr), copper-oxide wire particles and the FAMACHAr System (FAMACHA). This project is evaluating the field application of 3 scenarios for controlling nematode infection in mature ewes (Trial 1) and weaned goat kids (Trial 2) (Louisiana State University) and weaned lambs (Trial 3) (USDA ARS Booneville, AR). Similar experimental protocols are being followed for all three trials with three treatment groups per trial. Trial 1 began in February, 2004 and Trials 2 and 3 began in June, 2004. In February, 2004 at Louisiana State University, 30 pregnant F1 (Suffolk x Gulf Coast Native) ewes were allocated to
three groups of ten animals each based on fecal egg count and weight. At weaning, lambs were put on a different study. In June, 2004 at Louisiana State University and USDA ARS, Booneville, 30 mixed breed goat kids and 30 blackface lambs, respectively, were purchased and allocated to three groups of ten animals each based on fecal egg count and weight. Group 1 is serving as a control. All animals are being dewormed at four week intervals. The initial and subsequent dewormings have been with levamisole. Efficacy is being determined using the fecal egg count reduction (FECR) test. Group 2 is using the FAMACHA system where individual animals are being dewormed with moxidectin when scored as needing deworming using the FAMACHA eye color chart (score of 4-5 for sheep and 3-5 for kids). Group 3 is integrating the use of moxidectin, smart drenching, copper-oxide wire particles (COWP) and FAMACHA. All animals were dewormed initially with moxidectin. When infection level increased, all animals
were given a capsule containing two grams of COWP. FAMACHA monitoring is being used during periods between treatments to identify individual animals that need deworming independent of the mass treatments. These animals are being dewormed with a combination of albendazole and levamisole (smart drenching). To date, data collected indicates that the three scenarios are adequately controlling nematode infection in all trials. The efficacy of levamisole is becoming less which might be expected (relative resistance), so a switch to another anthelmintic may be necessary for the ewe trial. The kid and lamb trials are scheduled to end in October so levamisole was used throughout those trials. Final analysis of the effect of the three scenarios on infection and economics for the kid and lamb trials is expected to be completed by December, 2004. The ewe trial will continue through weaning, 2005.
Impacts
Various aspects of this integrated approach to control may prove beneficial for practical application. Thus, reliance of chemical dewormers may be alleviated.
Publications
- Burke, J.M., Miller, J.E., Olcott, D.D., Olcott, B.M., Terrill, T.H., 2004. Dose of copper oxide wire particles (COWP) and feed supplement level influences Haemonchus contortus infection in lambs. Vet Parasitol 123, 235-243.
- Burke, J.M., Miller, J.E., 2005. Use of copper oxide wire particles (COWP) in pregnant ewes. Proc 4th Inter Conf Novel Approaches to the Control of Helminth Parasites of Livestock: 27.
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