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Disease monitoring in free-ranging wildlife is a challenge and often relies on passive surveillance. Alternatively, proactive surveillance that relies on the detection of specific antibodies could give more reliable and timely insight into disease presence and prevalence in a population, especially if the evidence of disease occurs below detection thresholds for passive surveillance. Primary binding assays, like the indirect ELISA for antibody detection in wildlife, are hampered by a lack of species-specific conjugates. In this study, we developed anti-kudu (Tragelaphus strepsiceros) and anti-impala (Aepyceros melampus) immunoglobulin-specific conjugates in chickens and compared them to the binding of commercially available protein-G and protein-AG conjugates, using an ELISA-based avidity index. The conjugates were evaluated for cross-reaction with sera from other wild herbivores to assess future use in ELISAs. The developed conjugates had a high avidity of >70% against kudu and impala sera. The commercial conjugates (protein-G and protein-AG) had significantly low relative avidity (<20%) against these species. Eighteen other wildlife species demonstrated cross-reactivity with a mean relative avidity of >50% with the impala and kudu conjugates and <40% with the commercial conjugates. These results demonstrate that species-specific conjugates are important tools for the development and validation of immunoassays in wildlife and for the surveillance of zoonotic agents along the livestock-wildlife-human interface. [ABSTRACT FROM AUTHOR]

In the globally significant, lowland terrestrial systems of the sub-Antarctic's South Indian Ocean Province Islands, caterpillars of the flightless moth genus Pringleophaga (Lepidoptera: Tineidae) are typically responsible for much nutrient turnover., On Marion Island, Pringleophaga marioni is a keystone species for this reason., Rising temperatures have led to increasing populations of introduced house mice, which, in turn, feed extensively on Pringleophaga caterpillars., Because of the caterpillars' keystone role, predation by mice is leading to changes in the functioning of the terrestrial system., Given the estimates of an extended life cycle duration for P. marioni (and its congeners), that is, two to more than 5 years, an ongoing puzzle is why the species has not shown greater population declines on Marion Island than have been recorded (in some habitats 40-97% in 20 years), given extremely high estimates of predation ( c. 1% of standing biomass per day)., One reason may be inaccurate previous estimates of life cycle duration for the species., Here, we provide a new, quantitative estimate, by rearing caterpillars at different temperature regimes (5, 10, 15 and 5-15 °C), and combining these results with additional data from a prior study, to demonstrate that the life cycle duration for this species is approximately 1 year - half the previous minimum estimate., The new quantitative data provide grounds for improved models for estimating population persistence of this species, and information for models assessing the costs and benefits of conservation interventions such as the eradication of invasive house mice. [ABSTRACT FROM AUTHOR]