Livestock displace European mouflon from optimal foraging sites

Epidemiological surveillance of Neospora caninum in sheep (Ovis aries) and European mouflon (Ovis aries musimon) in southern Spain

Neospora caninum is a protozoan with a facultative heteroxenous life cycle, with canids as the definitive hosts and other mammals, mainly ruminants, acting as intermediate hosts. This parasite is recognized as one of the major abortifacient pathogens in cattle. Although reproductive disorders have also been reported in other domestic and wild ruminants, epidemiological data on N. caninum in ruminant species other than cattle is still limited. Here, we evaluate the seroprevalence and risk factors associated with N. caninum exposure in sheep (Ovis aries) and European mouflon (Ovis aries musimon) in southern Spain. Serum samples from 390 sheep and 387 free-ranging mouflons were tested for antibodies against N. caninum using in-house time-resolved fluorescence immunoassay based on NcGRA7 as a recombinant antigen. The individual seroprevalence was 26.2 % (95 %CI: 22.0-30.7) in sheep and 5.7 % (95 %CI: 3.8-8.5) in mouflons. At least one seropositive animal was detected in all the 26 sheep farms (100 %) and in eight of the 18 (44.4 %) hunting estates sampled. The presence of dogs on the farm (≥3) and the sheep breed (purebred) were potential risk factors associated with exposure to N. caninum in sheep. Our results indicate a high circulation of N. caninum in sheep farms in southern Spain. Control measures should be implemented to limit the exposure to this protozoan in sheep flocks. Although we have confirmed for the first time the presence of anti- N. caninum antibodies in European mouflon in Spain, and, despite the relatively low seroprevalence found, the impact of this parasite on mouflon populations should be further studied.

How we look: European wild mouflon and feral domestic sheep hybrids

Hybridization between wild animals and feral individuals from closely related domestic species can occur when they share the same habitat. Such events are generally regarded as a threat to the genetic integrity and survival of established wild populations. The aim of this study is to confirm a hybridization between European mouflon and feral sheep on the Adriatic island Dugi Otok, where a group of individuals phenotypically indicative of a possible introgression was photographed. Using an ovine medium-density SNP array genotypes, we provided genetic evidence of recent gene admixture between the two species. The ADMIXTURE analysis suggests that two hybrid individuals had 82.2% and 94.1% of their ancestry attributable to feral sheep, respectively, with the rest of the mouflon in origin. NEWHYBRIDS analysis estimated the combined probabilities for the putative hybrid individuals belonging to one of the hybrid classes at 87.0% and 90.1%, respectively. The main phenotypic differences in the hybrids were observed in the shape of the horns, a stronger horn circumference than in the mouflon and weaker than for the sheep, pronounced horn rings, a shorter tail, and intermediate color. We therefore recommend constant monitoring of the purity of the mouflon population to maintain its genetic integrity. In addition, all feral sheep should be removed from the wild, and released sheep raised in semi-wild conditions should be better controlled.

Impacts of Population Size and Domestication Process on Genetic Diversity and Genetic Load in Genus Ovis

In theoretical biology, a prevailing hypothesis posits a profound interconnection between effective population size (Ne), genetic diversity, inbreeding, and genetic load. The domestication and improvement processes are believed to be pivotal in diminishing genetic diversity while elevating levels of inbreeding and increasing genetic load. In this study, we performed a whole genome analysis to quantity genetic diversity, inbreeding, and genetic load across seven wild Ovis species and five domesticated sheep breeds. Our research demonstrates that the genetic load and diversity of species in the genus Ovis have no discernible impact on recent Ne, and three species within the subgenus Pachyceros tend to carry a higher genetic load and lower genetic diversity patterns. The results coincide with these species' dramatic decline in population sizes within the subgenus Pachyceros ~80-250 thousand years ago. European mouflon presented with the lowest Ne, lower genetic diversity, and higher individual inbreeding coefficient but a lower genetic load (missense and LoF). This suggests that the small Ne of European mouflon could reduce harmful mutations compared to other species within the genus Ovis. We showed lower genetic diversity in domesticated sheep than in Asiatic mouflon, but counterintuitive patterns of genetic load, i.e., lower weak genetic load (missense mutation) and no significant difference in strong genetic load (LoF mutation) between domestic sheep and Asiatic mouflon. These findings reveal that the "cost of domestication" during domestication and improvement processes reduced genetic diversity and purified weak genetic load more efficiently than wild species.

Artificial Water Troughs Use by the Mountain Ungulate Ovis gmelini ophion (Cyprus Mouflon) at Pafos Forest

For large herbivores inhabiting arid/semi-arid environments, water can be a limiting resource affecting their distribution and abundance for periods when water requirements are not met via forage. The Cyprus mouflon (Ovis gmelini ophion) is such a species, which is endemic to the mountain habitats of Cyprus. Recognizing water scarcity to be a major pressure to the mouflon, and with global warming projected to intensify hot and dry periods in the region, the Game and Fauna Service has been maintaining a network of locally designed watering troughs in Pafos Forest-the mouflon's stronghold-since 1997. This study describes the mouflon's use of the water troughs and examines whether visitation rates differed at the daily or weekly scale in response to environmental, climatic or anthropogenic parameters. Using camera traps, ten troughs were monitored from September 2017 to March 2018 (1,065 days; range 29-164 days per trough). Mouflon were detected at seven troughs (mean herd size 1.5 ± 1.2) during 373 independent detections (≥30 min interval between photographs), with visits peaking during late morning and midday hours. Generalized mixed-effect models showed mouflon visiting water troughs more frequently during hotter days, regardless of recent precipitation. Visits were also more frequent at water troughs located close to tar roads. Moreover, there was no evidence of mouflon avoiding water troughs used by predators (red foxes, feral dogs) at either daily or weekly scale, or during hunting days. The study supports the value of artificial water troughs for mediating, partially at least, the effects of climate change on mountain ungulates such as the Cyprus mouflon. Additional studies are proposed that will examine both mouflon drinking patterns across all seasons and ways of improving the effectiveness of the current water trough grid.