Field efficacy of flumethrin pour-on against Psoroptes ovis in cattle

Abstract

The field efficacy of pour-on formulation of flumethrin 1 per cent was assessed in cattle naturally infested with Psoroptes ovis. In a finishing unit, 18 infested animals were selected, left untreated for one month and examined twice to monitor the progress of the infestation. They were treated twice 10 days apart with a pour-on formulation of flumethrin 1 per cent (2 mg/kg bodyweight). Skin samples were collected from the animals on days 0, 7, 14, 28 and 42 and examined for the presence of live mites. The clinical condition of the cattle was evaluated at the beginning and at the end of the trial using a standardised chart. Bodyweights were recorded on days -32, 0, 28 and 50. In addition the 65 cows in a calving unit were given the same treatment regimen and its efficacy was evaluated on days 0, 7, 14 and 28 in 11 P ovis infested animals. On the day of treatment most of the infested animals had a severe pyodermatitis. From day 7 onwards no live mites were found in the treated animals and there was a marked clinical improvement. The percentage efficacy on day 28 was 100 per cent in both units. In the finishing animals treatment was associated with a marked improvement in daily weight gains between day 0 and day 28.

Efficacy of emamectin benzoate against sea lice infestations of Atlantic salmon, Salmo salar L.: evaluation in the absence of an untreated contemporary control

“…SLICE ® treatments on Atlantic salmon grow‐out sites in Maine are only administered after clear demonstration of natural infestation (prophylactic marine treatments are not allowed under the current INAD); and because lice counts are performed frequently, the degree of natural challenge can be estimated by parasite loads pretreatment. Consequently, the use of an alternative method that calculates efficacy as a proportional‐reduction relative to baseline infestation in the same population (Abbott 1925; Losson & Lonneux 1992; Ramstad, Colquhoun, Nordmo, Sutherland & Simmons 2002), rather than an untreated control group, is unlikely to lead to serious bias. We demonstrate the feasibility of efficacy evaluation in the absence of untreated controls using field data from Atlantic salmon farmed in the Cobscook Bay region of Maine and treated with SLICE ® during the years 2002–2005.…”

In vitro tests for evaluation of the hatchability of the eggs of Psoroptes mites following exposure to acaricidal compounds

“…Although most studies on the efficacy of acaricides on Psoroptes spp. have been performed in vivo (Durez & Hargot, 1977; Roberts et al ., 1978; Meleney & Roberts, 1979; Detry, 1985; Wright, 1986; Lonneux & Losson, 1992; Losson & Lonneux, 1992; Lonneux et al ., 1997), more recently increasing interest has been given to in vitro techniques for the evaluation of existing and candidate molecules (Perrucci et al ., 1994, 1995; Mignon & Losson, 1996; Coles & Stafford, 1999). However, most of these trials have been performed on adult mites.…”