Endemic lizard Gallotia galloti is a paratenic host of invasive Angiostrongylus cantonensis in Tenerife, Spain

Angiostrongylus cantonensis is an invasive zoonotic nematode which causes eosinophilic meningitis in accidental hosts – vertebrates including humans – and is known to impact wildlife. Even though the parasite originates in Southeast Asia, it has spread worldwide, especially into fragile island ecosystems. The Canary Islands are a biodiversity hot spot with numerous endemic species affected by biological invasions. Among others, Rattus rattus and Rattus norvegicus threaten many endemic species by predation and may spread invasive pathogens, such as the rat lungworm A. cantonensis , which was first described in Tenerife in 2010. Since it is known that lizards can act as paratenic hosts for A. cantonensis and Gallotia galloti is a lizard abundant in Tenerife, the aim of this study was to reveal the role of these endemic lizards in the parasite's life cycle. Gallotia galloti were captured in Tegueste, Tenerife, and after euthanasia, liver and tail muscle samples were examined for the presence of A. cantonensis . During microscopic examination, 8/36 liver samples (22.2%) contained granulomas with nematode larvae. In total, 10/39 liver samples (25.6%) and 7/36 tail muscle samples (19.4%) were positive for A. cantonensis DNA using qPCR. This is a first report of a reptile endemic to the Canary Islands acting as paratenic host of A. cantonensis . The fact that the parasite is obviously well-established in the island ecosystem and exploits endemic lizards as hosts may have important implications for the parasite's ecoepidemiology. Moreover, the parasite might threaten other species which depend on lizards in the island trophic web.

Estimation of the dietary nutrient profile of free-roaming feral cats: possible implications for nutrition of domestic cats

Cats are strict carnivores and in the wild rely on a diet solely based on animal tissues to meet their specific and unique nutritional requirements. Although the feeding ecology of cats in the wild has been well documented in the literature, there is no information on the precise nutrient profile to which the cat's metabolism has adapted. The present study aimed to derive the dietary nutrient profile of free-living cats. Studies reporting the feeding habits of cats in the wild were reviewed and data on the nutrient composition of the consumed prey items obtained from the literature. Fifty-five studies reported feeding strategy data of cats in the wild. After specific exclusion criteria, twenty-seven studies were used to derive thirty individual dietary nutrient profiles. The results show that feral cats are obligatory carnivores, with their daily energy intake from crude protein being 52 %, from crude fat 46 % and from N-free extract only 2 %. Minerals and trace elements are consumed in relatively high concentrations compared with recommended allowances determined using empirical methods. The calculated nutrient profile may be considered the nutrient intake to which the cat's metabolic system has adapted. The present study provides insight into the nutritive, as well as possible non-nutritive aspects of a natural diet of whole prey for cats and provides novel ways to further improve feline diets to increase health and longevity.

Food habits of feral cats (Felis silvestris catus L.) in insular semiarid environments (Fuerteventura, Canary Islands)

In this study, we present the first data on diet and impacts of feral cats on a semiarid island (Fuerteventura, Canary Islands). A total of 614 prey was identified in the 209 scats analysed. Introduced mammals, especially rabbits and mice, were the most consumed vertebrate prey and constituted more than 90% of biomass. Barbary ground squirrels, Algerian hedgehogs, and rats were preyed upon less even though they were abundant on the island. Invertebrates, mainly Orthoptera, Coleoptera, Hymenoptera and Odonata, were the second most important prey items (in terms of actual numbers) but they contributed only minimally with respect to biomass (<1.1%). The presence of terrestrial molluscs in the diet was interesting because they are a rare prey in an insular context. Birds and reptiles occurred at a low frequency. A total of 677 seeds was counted, mainly belonging to Lycium intricatum (Solanaceae) and two unidentified plant species. Levin’s niche breadth was narrow due to the high consumption of mammals. Morisita’s index showed a similar trophic overlap in diet with respect to the other xeric habitats of the Canarian archipelago. Considering that more than 90% of biomass corresponded to introduced mammals, we conclude that feral cats are not having a large direct impact on the native prey species.