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The red fox acts as reservoir for several helminthic infections which are of interest for both public and animal health. Huge efforts have been made for the assessment of the sensitivity of coprological tests for the detection of Echinococcus multilocularis, while less attention has been paid to other helminthic species. This study aimed at assessing the performance of two copromicroscopic techniques in the detection and prevalence estimation of gastrointestinal helminths in the red fox. Helminths were isolated from the small intestines of 150 red foxes from Bolzano province, Italy, with a scraping, filtration and counting technique (SFCT) and morphologically identified. Rectal contents were collected and submitted to simple flotation (FT) and, only for Taenids, a method based on the concentration of eggs and identification with multiplex PCR (CMPCR). Using SFCT as a reference standard, we estimated the sensitivity of the copromicroscopic tests. Three species of nematodes (namely, Toxocara canis, Uncinaria stenocephala and Pterygodermatites sp.) and five species of cestodes (E. multilocularis, Taenia crassiceps, T. polycantha, Hydatigera taeniaeformis, Mesocestoides sp.) were identified with SFCT, whereas eggs referable to the same taxa were detected with fecal diagnostics, except for Pterygodermatites sp. and Mesocestoides sp. The sensitivity of FT was low for all taxa, ranging from 9.8 to 36.3%, with lower values for Taeniidae. CMPCR was confirmed to perform better for the detection of Taeniidae eggs (23.5%) and the multiplex PCR on retrieved eggs was effective in the identification of the species. A meta-analysis of literature also suggested that our results are consistent with existing data, indicating that copromicroscopy tends to underestimate the prevalence of helminthic infections. The extent of such underestimation varies with taxon, being higher at high prevalence levels, in particular for cestodes. Irregular dynamics of egg shedding, and routine deep freezing of red fox feces may explain the frequency of false negatives with copromicroscopy. Low sensitivity of copromicroscopic tests should be accounted for when estimating prevalence and when defining the correct sample size for the detection of the parasites.

Since 1995, the Alpine chamois (Rupicapra r. rupicapra) population of the Dolomites has been affected by sarcoptic mange with considerable management concerns. In this study, 15 years (2006–2020) of passive surveillance and demographic data were analyzed in order to describe a mange outbreak. Furthermore, an enhanced passive surveillance protocol was implemented in order to evaluate the efficiency of ordinary vs. enhanced surveillance protocol in identifying dead chamois in the field and in reaching a correct diagnosis. Our results confirm the role of mange as a determining factor for chamois mortality, while stressing the importance of a wider view on the factors affecting population dynamics. The enhanced passive surveillance protocol increased the probability of carcass retrieval and identification of the cause of death; however, its adoption may be too costly if applied for long periods on a wide scale. Passive surveillance, in both ordinary and enhanced surveillance protocol, should encompass the use of other strategies in the future to study the eco-epidemiology of the disease in wild Caprinae.

The sarcoptic mange epizootic affecting chamois in the Dolomites Alps since 1995 has risen considerable concern in a management and conservation perspective, due to its strong impact on chamois and ibex populations. A remarkable amount of data has been collected by different wildlife research and management institutions, in order to analyze mange patterns and develop possible strategies to control the disease. The present study is aimed at providing a population-related figure of the spatial and temporal dynamics of clinical sarcoptic mange in alpine chamois, proposing an approach in which relevant basic concepts and parameters, as the definition of the epidemic front and its spreading speed, can be estimated and framed. The epidemic front was referred to the different mountain massifs, corresponding to well established management units of the chamois in the study area; moreover, the mange-related mortality peak at the massif level was used (in substitution of the index case/s) for temporal analysis of the disease spreading. Two speeds of the front have been estimated: a first raw average speed of about 3.38 km/year, and a second refined speed of 4.64 ± 3.12 km/year, more consistent to the variability in the field. The time series analysis showed that the impact of mange increases over the late winter months, reaching a peak in early spring.Our results strengthen the conclusions of previous studies, proposing a new frame to include other studies in progress on the alpine chamois-Sarcoptes interactions.Download the complete issue.