Production benefits from pre- and post-lambing anthelmintic treatment of ewes on commercial farms in the southern North Island of New Zealand

Abstract

Anthelmintic treatments administered to ewes around lambing resulted in variable responses between farms and years, which in some trials were negative for some variables, and some of the variability was due to the mineral component of the CRC. The widespread perception amongst farmers and veterinarians that anthelmintic treatment of ewes around lambing will always result in positive benefits is not supported.

A cost-benefit analysis of pre- and post-lambing anthelmintic treatments to twin-bearing ewes on commercial farms in the southern North Island of New Zealand

“…In general, in all experiments, there was a positive response to treatment in both ewe and lamb liveweight at weaning (Miller et al 2015). Lambs from treated ewes were, on average, heavier than lambs from untreated ewes, but this did not uniformly translate into increased weight of lamb weaned per treated ewe (Miller et al 2015).…”

“…Another treatment involved the oral treatment administered at tail docking 3-4 weeks post-lambing. Along with an untreated control, all trials also included a mineral supplementation treatment consisting of a long-acting formulation of Se and vitamin B 12 (to combat Co deficiency) in an attempt to differentiate the effect of the anthelmintic and mineral components within the CRC (Miller et al 2015). Details of the treatments are given in Table 1.…”

“…Details of the experimental design, methods and productivity data analysis are described in detail in Miller et al (2015). Here we ascribe financial values to the costs and production variables measured in the on-farm trials in order to calculate net economic benefit values for the treatments in each trial, where a trial was that part of an experiment carried out on one farm in 1 year.…”

“…Here we ascribe financial values to the costs and production variables measured in the on-farm trials in order to calculate net economic benefit values for the treatments in each trial, where a trial was that part of an experiment carried out on one farm in 1 year. As outlined in Miller et al (2015) the study was divided into three experiments with overlapping components, designed to address different questions. Briefly, Experiment 1 evaluated the production response to a CRC containing abamectin, albendazole, Se and Co (CRC2) administered 2-3 weeks pre-lambing.…”

“…The trial work and economic analysis described here, and elsewhere (Miller et al 2015), was instigated by two farm business groups in the Wairarapa region of New Zealand in 2011. Members of the Whangaehu and Alfredton farm business groups were concerned that they had insufficient information regarding the effectiveness, economic benefit and associated risks of using CRC in their ewes over the lambing period i.e.…”