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A trial was conducted to investigate the response of mixed age ewes of different body condition scores (BCS) to a pre-mating treatment with long-acting anthelmintics. Three hundred Poll–Dorset Texel cross ewes were divided into three groups of 100 and treated pre-mating with either a 100-day controlled-release capsule containing abamectin, albendazole, selenium and cobalt, a long-acting injectable formulation of moxidectin or remained untreated. Initially, ewes of lower BCS showed a significantly larger response in liveweight gain and a BCS increase which approached significance. However, these benefits did not persist following the expiry of the anthelmintics. Although treated ewes gave birth to more lambs, by weaning there was no significant difference between treatment groups in any of the measured variables and no significant influence of ewe BCS at treatment. The results are similar to earlier studies which showed that the benefits measured at the end of a long-acting anthelmintic treatment may not persist and may over-estimate the true benefit. Although there was a temporary benefit to treatment of low BCS ewes the data in general supports the view that many factors contribute to low BCS in ewes and parasites are often only a minor contributor. [ABSTRACT FROM AUTHOR]

Background: Strongylid and ascarid parasites are omnipresent in equine stud farms, and ever‐increasing levels of anthelmintic resistance are challenging the industry with finding more sustainable and yet effective parasite control programs. Objectives: To evaluate egg count levels, bodyweight and equine health under defined parasite control protocols in foals and mares at two Standardbred and two Thoroughbred stud farms. Study design: Longitudinal randomised field trial. Methods: A total of 93 foals were enrolled and split into two treatment groups, and 99 mares were enrolled and assigned to three treatment groups. All horses underwent a health examination, and episodes of colic or diarrhoea were recorded at each faecal collection date. Bodyweights were assessed using a weight tape, and mares were body condition scored. Group A foals (FA) were dewormed at 2 and 5 months of age with a fenbendazole/ivermectin/praziquantel product, while group B foals (FB) were dewormed on a monthly basis, alternating between the above‐mentioned product and an oxfendazole/pyrantel embonate product. Group A mares (MA) were dewormed twice with fenbendazole/ivermectin/praziquantel, group B mares (MB) were dewormed with the same product, when egg counts exceeded 300 strongylid eggs per gram, and group C mares (MC) were dewormed every 2 months, alternating between the two products. Health data were collected monthly for 6 months (foals) and bimonthly for 13 months (mares). Data were analysed with mixed linear models and interpreted at the α = 0.05 significance level. Results: There were no significant bodyweight differences between foal groups, but MA mares were significantly lighter than the other two groups. Very few health incidents were recorded. Foals in group FA had significantly higher ascarid and strongylid egg counts, whereas no significant differences were observed between mare groups. Main limitations: Study duration limited to one season. Conclusions: Anthelmintic treatment intensity was lowered from the traditional intensive regimes without measurable negative health consequences for mares and foals. [ABSTRACT FROM AUTHOR]

Illthrift, defined as low body condition score (BCS), is a problem in adult ewes on many farms in New Zealand, and nematode parasites are often considered a significant contributing factor. Here we test the hypothesis that, over the lambing-lactation period, parasites are a significant causal factor in ewe illthrift, and that anthelmintic administration to low BCS ewes results in a greater improvement in condition than treatment of other ewes. Faecal nematode egg count (FEC) prior to lambing and ewe liveweight change over the study period were poorly correlated, and both were independent of pre-lambing BCS, as was ewe response to anthelmintic treatment. Some ewes lost, or gained, considerable amounts of weight independent of their BCS, the number and size of lambs reared, and anthelmintic treatment. We find no evidence that ewes of low BCS have higher FECs, or a larger response to anthelmintic treatment than ewes in better condition. [ABSTRACT FROM AUTHOR]

Blowflies cause a serious and debilitating disease of sheep in many countries. Reliance on the prophylactic use of chemicals for sheep protection is threatened by resistance and increasing awareness of the non-target and environmental consequences of their use. Further, consumer awareness of animal welfare issues is highlighting both the disease itself and some of the practices used to prevent it. Alternative approaches to fly control will likely be needed in future to maintain production and welfare levels. A range of fungal and bacterial pathogens are known to attack blowflies with some previously being investigated as potential biopesticides, however, to date none have been commercialised. Although much still remains to be discovered, the host–pathogen interaction appears complicated with the pathogen producing a range of compounds to facilitate invasion of the host and evasion of host defence mechanisms. While bacteria need to be ingested to infect a host, fungi appear to primarily invade through the cuticle. Fungal infection of adult flies can occur rapidly through the tarsi suggesting that only limited tactile contact is required. Many pathogens are intolerant of high temperatures such that their utility as prophylactic treatments, applied to sheep, may be limited. Also, while infected flies may not die rapidly, infection may result in behavioural changes and reduced fecundity, factors which need to be considered when evaluating the impact of pathogens. The use of pathogens in lure-and-kill strategies against adult flies or applied to pastures targeting pupal stages warrants further investigation. [ABSTRACT FROM AUTHOR]