Coprological analyses on apparently healthy Alpine ibex (Capra ibex ibex) from two Swiss colonies

Host movement dominates the predicted effects of climate change on parasite transmission between wild and domestic mountain ungulates

Climate change is shifting the transmission of parasites, which is determined by host density, ambient temperature and moisture. These shifts can lead to increased pressure from parasites, in wild and domestic animals, and can impact the effectiveness of parasite control strategies. Understanding the interactive effects of climate on host movement and parasite life histories will enable targeted parasite management, to ensure livestock productivity and avoid additional stress on wildlife populations. To assess complex outcomes under climate change, we applied a gastrointestinal nematode transmission model to a montane wildlife-livestock system, based on host movement and changes in abiotic factors due to elevation, comparing projected climate change scenarios with the historic climate. The wildlife host, Alpine ibex (Capra ibex ibex), undergoes seasonal elevational migration, and livestock are grazed during the summer for eight weeks. Total parasite infection pressure was more sensitive to host movement than to the direct effect of climatic conditions on parasite availability. Extended livestock grazing is predicted to increase parasite exposure for wildlife. These results demonstrate that movement of different host species should be considered when predicting the effects of climate change on parasite transmission, and can inform decisions to support wildlife and livestock health.

Protostrongylus caprae Zdzitowiecki et Boev, 1971 (Nematoda: Protostrongylidae) - First record in Alpine ibex (Capra ibex Linnaeus, 1758) from Europe

In the course of a survey of the endoparasites of Alpine ibex (Capra ibex) from Austria, examination of the lungs revealed male Protostrongylus nematodes presenting morphological characters which differed from those of the three Protostrongylus species previously reported from this host. Fragments of 16 adult male and 4 adult female nematodes extracted from the lung tissue of two female ibex following peptic digestion were subjected to close microscopic examination. Based on their morphology, the lungworms were identified as Protostrongylus caprae Zdzitowiecki et Boev, 1971. This species was originally described from Siberian ibex (Capra sibirica) in Asia and previously only reported from this host from Kazakhstan and Mongolia. The identification of P. caprae in Alpine ibex represents a new host and geographical record and reinforces the interest to further study the parasite diversity of wild ungulates for a better understanding of complex host-parasite associations and biogeography.

Eimeria infections in domestic and wild ruminants with reference to control options in domestic ruminants

Eimeria infections are commonly seen in a variety of mammalian hosts. This genus of unicellular sporozoan parasites causes significant disease (coccidiosis) in different livestock species leading to economic losses for agricultural producers. Especially the production of cattle, sheep, and goat is strongly dependent on efficient coccidiosis control. However, many other livestock hosts like, e.g., camelids, bison, rabbits, and guinea pigs may benefit from reduced parasite transmission and targeted control measures as well. Besides livestock, also wildlife and pet animals may be affected by Eimeria infections resulting in clinical or subclinical coccidiosis. Wildlife herd health is crucial to conservation efforts, and Eimeria species are a prevalent pathogen in multiple mammalian wildlife species. This review aims to highlight the epidemiology of mammalian Eimeria infections in both wild and domestic ruminants, including host specificity, transmission, survival of environmental oocysts, occurrence, and risk factors for infection. Understanding general drivers of Eimeria infection may support adequate livestock and wildlife management. Furthermore, control options for livestock with reference to management factors, drug application, and alternative approaches are discussed. The goal of Eimeria control should be to reduce pathogen transmission in different host species and to improve sustainable livestock production. Controlling Eimeria infections in livestock is important considering both their animal welfare impact and their high economic relevance.

Detection of Zoonotic Cryptosporidium ubiquitum in Alpine Wild Ruminants

Cryptosporidium is a widespread apicomplexan protozoan of major zoonotic importance, characterized by a wide host range, and with relevant economic implications and potential negative effects on livestock and wildlife population dynamics. Considering the recent strong demographic increase of alpine ungulates, in this study, carried out in the Italian Northwestern Alps, we investigated the occurrence of Cryptosporidium spp. in these species and their potential involvement in environmental contamination with Cryptosporidium spp. oocysts. The immune-enzymatic approach revealed a Cryptosporidium prevalence of 1.7% (5/293), 0.5% (1/196) and 3.4% (4/119) in alpine chamois (Rupicapra rupicapra), red deer (Cervus elaphus) and roe deer (Capreolus capreolus), respectively. Positive samples were subjected to polymerase chain reaction (PCR) amplification for the COWP and gp60 genes. The presence of Cryptosporidium was confirmed in one chamois and four roe deer. Sequences obtained clustered within Cryptosporidium ubiquitum, currently recognized as an emerging zoonotic species. This finding represents the first detection of zoonotic C. ubiquitum in chamois and in the Alpine environment. Despite the low observed prevalences, environmental contamination by oocysts could play a role as a potential source of infections for humans and livestock.

Bronchopulmonary Nematodes in Alpine Ibex: Shedding of First Stage Larvae Analyzed at the Individual Host Level

Pneumonia is the most frequent cause of death for Alpine ibex (Capra ibex) in Gran Paradiso National Park, (Italy). The etiology of this form of pneumonia is currently unknown and the identification of the primary etiological agent remains difficult due to biological and logistic constraints. Uncovering individual differences in Protostrongylid prevalence and intensity is important to further investigate the epidemiology of respiratory diseases and their relationship to heterozygosity and inbreeding in a once almost extinct population like C. ibex. In a group of 21 individually recognizable adult male we monitored monthly prevalence and intensity of Protostrongylid first-stage larvae using Baerman's technique from June to September 2019. First-stage larvae of 5 genera were detected. Muellerius (P = 100%, CI_95% = 84–100) and Protostrongylus (P = 86%, CI_95%:71–100) were two dominant genera according to Bush's importance index. Neostrongylus (P = 38%,CI_95%: 17–59), Cystocaulus (P = 33%,CI_95% = 13–53) were classified as co-dominant genera while Dictyocaulus filaria (P = 0.05%, CI_95% = 0.04–0.13) was detected, for the first time in Alpine ibex, in one subject. Protostrongylidae larval excretion varied significantly over time, with minimum L1 excretion in July. Individual median larval intensity ranged from 4.4 lpg to 82.2 lpg with Poulin's discrepancy index showing highly aggregated distribution patterns for Muellerius spp. (D = 0.283, CI_95% = 0.760–0.895) and Protostrongylus spp. (D = 0.635, CI_95% = 0.580–0.705). Presented data provide the necessary base point to further investigate how lungworm infection account for the different rates of progression of pneumonia in C. ibex. Individual aggregation of larval intensity must be further evaluated to determine whether these differences mirror different levels of parasitic infection related to individual differences in immune response, hormonal-states or genetic fitness.

Evaluation of the Baermann-Wetzel method for detecting lungworm larvae in wild ruminants from faecal samples

Lungworms can exert a negative impact on wild ruminant fitness; for this reason, the diagnosis of the associated diseases is an important prevention measure. The Baerman-Wetzel technique is the most usual method for the diagnosis of bronchopulmonary nematodes and is based on the active migration and movement of their first-stage larvae. Pulmonary tissue samples are frequently used for the post-mortem diagnosis of these parasites, but this kind of sample is not always available and easy to obtain. Faecal samples represent a more accessible choice for parasite monitoring. This work aimed to evaluate the agreement between the results obtained by the Baermann-Wetzel technique when samples of lung parenchyma or faeces from wild ruminants are used. A good level of agreement as well as a similar sensitivity between the two types of sample were observed, validating the use of faecal samples as a less invasive and cost-effective alternative for the monitoring of lungworm in wild ruminant populations.

Diversity of Eimeria Species in Wild Chamois Rupicapra spp.: A Statistical Approach in Morphological Taxonomy

Wildlife is frequently infected by intestinal protozoa, which may threaten their fitness and health. A diverse community of Eimeria species is known to occur in the digestive tract of mountain-dwelling ungulates, including chamois (genus Rupicapra). However, available data on Eimeria diversity in these taxa is at times inconsistent and mostly dated. In the present study, we aimed to revisit the occurrence of Eimeria spp. in the Alpine subspecies of the Northern chamois (Rupicapra rupicapra rupicapra) and the Apennine subspecies of the Southern chamois (Rupicapra pyrenaica ornata) in Italy, using an integrated approach based on a hierarchical cluster analysis (HCPC) applied to oocyst morphology and morphometry. A total of 352 fecal samples were collected from R. r. rupicapra (n = 262) and R. p. ornata (n = 90). Overall, 85.3% (300/352) of the animals tested microscopically positive to Eimeria spp. Based on morphological analysis, we identified all the eimerian species described in chamois. Through the HCPC method, five clusters were generated, corresponding to E. suppereri, E. yakimoffmatschoulskyi, E. riedmuelleri (two different clusters), and E. rupicaprae morphotypes. The well-defined clusters within E. riedmuelleri support the existence of two distinct morphological groups, possibly referable to different taxonomic units. This study suggests that combining a morphometrical approach with a powerful statistical method may be helpful to disentangle uncertainties in the morphology of Eimeria oocysts and to address taxonomic studies of eimeriid protozoa at a specific host taxon level.

Lungworms in Alpine ibex (Capra ibex) in the eastern Alps, Italy: An ecological approach

Host-parasite relationships have been frequently investigated in mountain dwelling ungulates, though mostly focusing on gastrointestinal nematodes. On the contrary, very few studies were conducted on broncopulmonary nematodes, which may result in severe parenchymal lesions and act as predisposing factor for multifactorial pneumonia. The epidemiological and ecological features of lungworms infecting an Alpine ibex population in the Eastern Alps, Italy, were non-invasively investigated by means of a modified Baermann technique with an original quantitative methodology. Out of a total of 269 samples collected monthly from July to November 2013 and from July to October 2014, 212 (78.8%) were positive for Muellerius and 26 (9.7%) for Protostrongylus, whereas Neostrongylus and Cystocaulus were less prevalent (4.1% and 0.7%, respectively). None of the investigated samples tested positive for dictyocaulids. The genus Muellerius showed the highest larval output intensity (134.2 L1/g), followed by Protostrongylus with 33.8 L1/g. A contrasting age-related pattern of Muellerius and Protostrongylus was revealed, with the former significantly more prevalent and abundant in adult animals, while the latter in kids. Due to the limited accessibility of the study area during winter and spring, it was difficult to describe clear seasonal trends in larval output, although Muellerius showed a minimum in the late summer and a rise in the autumn. The newly developed diagnostic method showed a fair repeatability, thus representing an interesting tool to investigate the ecology of lungworms in protected species, such as the A. ibex. Based on results, ibex in the Marmolada massif seem to have an ecologically stable relationship with their lungworm community.

Prevalence, molecular characterization and zoonotic potential of Cryptosporidium spp. in goats in Henan and Chongqing, China

To estimate the prevalence and public health significance of cryptosporidiosis in goats in China, 1265 fecal samples from seven farms in Henan province and Chongqing city were examined for Cryptosporidium oocysts. The overall infection rate of Cryptosporidium spp. was 3.48% (44/1256). Significant difference was observed among age groups, with the post weaned kids having the highest infection rate (4.58%; ρ<0.01). Cryptosporidium spp. were characterized by PCR-restriction fragment length polymorphism (RFLP) analysis and DNA sequence analysis of the small subunit (SSU) rRNA gene. The SSU rRNA-based PCR identified three Cryptosporidium species, including Cryptosporidium ubiquitum (24/44) in Henan and Chongqing, and Cryptosporidium andersoni (16/44) and Cryptosporidium xiaoi (4/44) in Henan. Among which, the C. ubiquitum and C. andersoni were first identified in goats thus far and were found in all age groups except no C. andersoni being found in the postparturition nannies, whereas the C. xiaoi was detected in pre-weaned kids and pregnant nannies. Subtyping C. ubiquitum by DNA sequence analysis of the 60 kDa glycoprotein (gp60) gene suggested the isolates identified all belonged to zoonotic XIIa subtype 2. Thus, the dominant C. ubiquitum found in this study and the XIIa subtype 2 has been found in humans indicated goats are a potential source for zoonotic infections with the C. ubiquitum. More studies are needed for better understanding of differences in the transmission and public health significance of cryptosporidiosis in goats.

Wildlife health investigations: needs, challenges and recommendations

In a fast changing world with growing concerns about biodiversity loss and an increasing number of animal and human diseases emerging from wildlife, the need for effective wildlife health investigations including both surveillance and research is now widely recognized. However, procedures applicable to and knowledge acquired from studies related to domestic animal and human health can be on partly extrapolated to wildlife. This article identifies requirements and challenges inherent in wildlife health investigations, reviews important definitions and novel health investigation methods, and proposes tools and strategies for effective wildlife health surveillance programs. Impediments to wildlife health investigations are largely related to zoological, behavioral and ecological characteristics of wildlife populations and to limited access to investigation materials. These concerns should not be viewed as insurmountable but it is imperative that they are considered in study design, data analysis and result interpretation. It is particularly crucial to remember that health surveillance does not begin in the laboratory but in the fields. In this context, participatory approaches and mutual respect are essential. Furthermore, interdisciplinarity and open minds are necessary because a wide range of tools and knowledge from different fields need to be integrated in wildlife health surveillance and research. The identification of factors contributing to disease emergence requires the comparison of health and ecological data over time and among geographical regions. Finally, there is a need for the development and validation of diagnostic tests for wildlife species and for data on free-ranging population densities. Training of health professionals in wildlife diseases should also be improved. Overall, the article particularly emphasizes five needs of wildlife health investigations: communication and collaboration; use of synergies and triangulation approaches; investments for the long term; systematic collection of metadata; and harmonization of definitions and methods.