A framework for evaluation of on-farm mastitis diagnostics in Australia

Numerous culture-based diagnostics are available on the Australian and international markets for on-farm detection of bacterial pathogens in milk. Use of such diagnostics may provide an opportunity to improve the prudent use of antimicrobials in udder health management. Farms are low-resource settings in terms of diagnostic microbiology capacity. The World Health Organisation has identified criteria for the evaluation of diagnostic tests in low resource settings based on Accuracy, Sensitivity, Specificity, User-friendliness, being Rapid or Robust, Equipment-free and being Deliverable (ASSURED). Here, we review how those criteria can be interpreted in the context of microbiological diagnosis of mastitis pathogens, and how on-farm diagnostics that are currently available in Australia perform relative to ASSURED criteria. This evaluation identifies multiple trade-offs, both with regard to scientific criteria and with regards to convenience criteria. More importantly, the purpose of testing may differ between farms, and test performance should be evaluated relative to its intended use. The ability of on-farm mastitis diagnostics to inform mastitis treatment decision-making in a timely and cost-effective manner depends not just on test characteristics but also on farm-specific pathogen prevalence, and on the farm enterprise's priorities and the farm manager's potential courses of action. With most assay evaluations to date conducted in professional laboratories, there is a surprising dearth of information on how well any of the diagnostic tests perform on-farm and, indeed, of the on-farm decision-making processes that they aim to inform.     

Status of wildlife health monitoring in the United Kingdom

There is a clear need to monitor the health of wildlife in the UK, to help to understand the population dynamics of endangered species and to detect any harm to the welfare of wild animals caused by human beings. Despite previous proposals, there has been little progress in the development of a national programme of monitoring. With notable exceptions, the current schemes for investigating the morbidity and mortality of wild animals cover only limited groups of animals and are fragmented and uncoordinated. They consist of statutory schemes of restricted scope, and studies in universities, institutes and wildlife rehabilitation centres with limited funding. As a result, significant disease incidents may remain undetected and others may not be investigated fully, posing risks to the welfare and conservation of wildlife, the welfare of domestic animals, and in some cases to human health. Coordinated national schemes for the surveillance of the health of wildlife are already established in France, the USA and Canada and their best characteristics could be used to develop a scheme for the UK.     

Studies on the mode of action of diflufenican in selected crop and weed species: Basis of selectivity of pre- and early post-emergence applications

Diflufenican, a pre- and early post-emergence herbicide, was found to be highly active against a wide range of weeds at application rates of 50–250 g ha-1. Studies on the mode of selectivity with [14C]diflufenican have demonstrated that selectivity between cereal crops and selected weed species is primarily due to differential uptake and indirectly to translocation; ‘depth protection’ appears to be the major reason for selectivity of soil-applied diflufenican.     

Enzyme-linked immunosorbent assay for the detection of antibodies to the sheep scab mite Psoroptes ovis

An enzyme-linked immunosorbent assay has been shown to detect antibodies in the circulation of sheep infected with Psoroptes ovis. Strong positive reactions were obtained from 19 sheep with four-month-old infections. No cross reaction was observed with sera obtained from sheep infected with either Fasciola hepatica, Nematodirus battus, Ostertagia circumcincta or Damalinia ovis.     

The efficacy of showers for control of ectoparasites of sheep.

Ectoparasites of sheep in Britain include the tick Ixodes ricinus, the blowfly, Lucilia sericata, the ked, Melophagus ovinus and the lice, Damalinia ovis and Linognathus ovillus. The most important ectoparasite, however, is the mite Psoroptes communis ovis which causes sheep scab. This notifiable disease was eradicated from Britain in 1952 but was reported again in 1973. The control of ectoparasites depends largely on the efficient application of insecticide to the fleece and skin. Plunge dipping in a bath is generally regarded as the most efficient method and is compulsory for the control of sheep scab but it is not always the most convenient. After the eradication of sheep scab in 1952 plunge dipping was no longer compulsory and jetting, spraying and showering techniques were then employed for the other ectoparasites.     

Acute cortisol responses of calves to scoop dehorning using local anaesthesia and/or cautery of the wound

Objective To measure plasma cortisol responses in calves dehorned using a scoop after administration of local anaesthesia and/or cautery of the wounds.
Design A physiological study with controls.
Procedure There were six treatments: control handling with and without local anaesthesia, dehorning, dehorning after local anaesthesia, dehorning followed by wound cautery, and dehorning after local anaesthesia followed by wound cautery. Blood samples were taken before and after dehorning.
Results Dehorning caused an increase in plasma cortisol concentrations, which decreased a little to plateau values and then declined to pretreatment values 3 to 4 h after dehorning. The peak was smaller after local anaesthesia was administered but when its effects wore off, cortisol concentrations increased and thereafter were similar to those in the dehorned animals. The combination of local anaesthesia and cautery resulted in a plasma cortisol response similar to those in control calves with or without local anaesthesia.
Conclusions If plasma cortisol concentrations reflect the distress being experienced by the calves, then local anaesthesia reduces the acute distress for about 3 h after dehorning but not during the subsequent 3 to 4 h. Combining local anaesthetic and cautery prevented the significant increase in plasma cortisol following dehorning and may eliminate the acute distress caused by scoop dehorning.