Effects of tail amputation and treatment with an albendazole controlled-release capsule on the health and productivity of prime lambs.
OBJECTIVE
To assess the effects of tail amputation and treatment with albendazole controlled-release capsule (CRC) on the health and productivity of prime lambs.


METHODS
Field trials on three farms.


METHODS
About 551 Coopworth-Poll Dorset cross, 588 Border Leicester-Merino-Poll Dorset cross and 575 Corriedale-Poll Dorset cross lambs.


METHODS
On three farms, lambs with amputated tails were compared with an equal number of lambs with tails left entire. In both of these groups half the lambs were treated with an albendazole CRC 13 weeks after the start of lambing. Faecal soiling of the breech and flystrike of the breech were recorded. Lambs were weighed and body condition scored at each visit and carcase weights and fat score of each lamb at slaughter. Procedures on the slaughter chain were monitored to determine whether the retention of the tail caused any problems.


RESULTS
There were no observed benefits of treatment with an albendazole CRC on the farms in the study. There was no strong evidence that tail amputation had any long-term effect on the growth rate of lambs or carcase traits. No detrimental effects were observed during processing of lambs with long tails in the abattoir. Lambs with entire tails had significantly greater mean dag scores than lambs with amputated tails. On one farm lambs with entire tails were at about twice the risk of requiring crutching and on another farm were at three times the risk of breech strike compared with lambs with amputated tails.


CONCLUSIONS
This study provides evidence that amputating the tail is not an absolute requirement to maintain the health and welfare of prime lambs, but leaving the tail of prime lambs entire is likely to increase chemical usage to control flystrike, and to increase the frequency of crutching.
Ware
J K
JK
Mackinnon Project, School of Veterinary Science, University of Melbourne, Werribee, Victoria 3030.
Vizard
A L
AL
Lean
G R
GR
D015766:Albendazole / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D000871:Anthelmintics / Q000494:pharmacology* / Q000627:therapeutic use; D003692:Delayed-Action Preparations; D003967:Diarrhea / Q000517:prevention & control / Q000662:veterinary; D005243:Feces / Q000469:parasitology; D005260:Female; D008297:Male; D009198:Myiasis / Q000517:prevention & control / Q000662:veterinary*; D012098:Reproduction / Q000187:drug effects*; D012756:Sheep / Q000254:growth & development / Q000601:surgery*; D012757:Sheep Diseases / Q000517:prevention & control*; D013623:Tail / Q000601:surgery*; D014739:Victoria
D000871:Anthelmintics; D003692:Delayed-Action Preparations; D015766:Albendazole