Limited historical admixture between European wildcats and domestic cats

Domestic cats were derived from the Near Eastern wildcat (Felis lybica), after which they dispersed with people into Europe. As they did so, it is possible that they interbred with the indigenous population of European wildcats (Felis silvestris). Gene flow between incoming domestic animals and closely related indigenous wild species has been previously demonstrated in other taxa, including pigs, sheep, goats, bees, chickens, and cattle. In the case of cats, a lack of nuclear, genome-wide data, particularly from Near Eastern wildcats, has made it difficult to either detect or quantify this possibility. To address these issues, we generated 75 ancient mitochondrial genomes, 14 ancient nuclear genomes, and 31 modern nuclear genomes from European and Near Eastern wildcats. Our results demonstrate that despite cohabitating for at least 2,000 years on the European mainland and in Britain, most modern domestic cats possessed less than 10% of their ancestry from European wildcats, and ancient European wildcats possessed little to no ancestry from domestic cats. The antiquity and strength of this reproductive isolation between introduced domestic cats and local wildcats was likely the result of behavioral and ecological differences. Intriguingly, this long-lasting reproductive isolation is currently being eroded in parts of the species' distribution as a result of anthropogenic activities.

Hepatozoon species infecting domestic cats from countries of the Mediterranean basin

Tick-borne diseases (TBDs) are caused by pathogens of human and veterinary concern representing a major public health issue worldwide. Although feline medicine has progressed much in the recent decades, data on feline TBDs (FeTBDs) remain scant. Therefore, this study aimed to assess the prevalence of apicomplexan parasite infections, associated risk factors and clinical-hematological abnormalities in domestic feline populations from countries of the Mediterranean basin. Blood and serum samples from cats (n = 600) living in France, Greece, Israel, Italy, Portugal and Spain were collected along with animal data (i.e., age, sex, breed, housing conditions and geographical origin), clinical signs and laboratory blood test parameters. Cats were grouped according to their age as kitten (up to one year), young (between one and six years), mature (between seven and ten years) and senior (older than ten years). Blood samples were tested for Hepatozoon spp. and piroplasmids by conventional PCR targeting 18S rRNA gene. The overall prevalence of Hepatozoon spp. infection was 14.5%, being significantly higher in cats from Greece (30%) and Portugal (23%), followed by Spain (15%), Israel (15%) and France (4%). Cats from Italy scored negative. Hepatozoon felis was identified in 86 animals, with three different sequence types and H. silvestris was detected in one shelter cat from Portugal. No piroplasmid DNA was amplified. The risk of Hepatozoon spp. infection was related to feline geographical provenience, housing condition and age. No statistical correlation was reported with any clinical signs, while increased alanine aminotransferase (ALT) activity was the only laboratory abnormality significantly associated (p = 0.03) with the infection. Data suggest a high circulation of H. felis, and only occasionally of H. silvestris, within domestic feline populations in the Mediterranean basin, mainly in shelter or free roaming and young cats with asymptomatic or subclinical infection.

The genetic integrity of the ex situ population of the European wildcat (Felis silvestris silvestris) is seriously threatened by introgression from domestic cats (Felis silvestris catus)

Studies on the genetic diversity and relatedness of zoo populations are crucial for implementing successful breeding programmes. The European wildcat, Felis s. silvestris, is subject to intensive conservation measures, including captive breeding and reintroduction. We here present the first systematic genetic analysis of the captive population of Felis s. silvestris in comparison with a natural wild population. We used microsatellites and mtDNA sequencing to assess genetic diversity, structure and integrity of the ex situ population. Our results show that the ex situ population of the European wildcat is highly structured and that it has a higher genetic diversity than the studied wild population. Some genetic clusters matched the breeding lines of certain zoos or groups of zoos that often exchanged individuals. Two mitochondrial haplotype groups were detected in the in situ populations, one of which was closely related to the most common haplotype found in domestic cats, suggesting past introgression in the wild. Although native haplotypes were also found in the captive population, the majority (68%) of captive individuals shared a common mtDNA haplotype with the domestic cat (Felis s. catus). Only six captive individuals (7.7%) were assigned as wildcats in the STRUCTURE analysis (at K = 2), two of which had domestic cat mtDNA haplotypes and only two captive individuals were assigned as purebred wildcats by NewHybrids. These results suggest that the high genetic diversity of the captive population has been caused by admixture with domestic cats. Therefore, the captive population cannot be recommended for further breeding and reintroduction.

Use of spatial capture-recapture modeling and DNA data to estimate densities of elusive animals

Assessment of abundance, survival, recruitment rates, and density (i.e., population assessment) is especially challenging for elusive species most in need of protection (e.g., rare carnivores). Individual identification methods, such as DNA sampling, provide ways of studying such species efficiently and noninvasively. Additionally, statistical methods that correct for undetected animals and account for locations where animals are captured are available to efficiently estimate density and other demographic parameters. We collected hair samples of European wildcat (Felis silvestris) from cheek-rub lure sticks, extracted DNA from the samples, and identified each animals' genotype. To estimate the density of wildcats, we used Bayesian inference in a spatial capture-recapture model. We used WinBUGS to fit a model that accounted for differences in detection probability among individuals and seasons and between two lure arrays. We detected 21 individual wildcats (including possible hybrids) 47 times. Wildcat density was estimated at 0.29/km² (SE 0.06), and 95% of the activity of wildcats was estimated to occur within 1.83 km from their home-range center. Lures located systematically were associated with a greater number of detections than lures placed in a cell on the basis of expert opinion. Detection probability of individual cats was greatest in late March. Our model is a generalized linear mixed model; hence, it can be easily extended, for instance, to incorporate trap- and individual-level covariates. We believe that the combined use of noninvasive sampling techniques and spatial capture-recapture models will improve population assessments, especially for rare and elusive animals.

The Taming of the cat. Genetic and archaeological findings hint that wildcats became housecats earlier--and in a different place--than previously thought

Genetic and archaeological findings hint that wildcats became house cats earlier—and in a different place—than previously thought

The late Miocene radiation of modern Felidae: a genetic assessment

Modern felid species descend from relatively recent (<11 million years ago) divergence and speciation events that produced successful predatory carnivores worldwide but that have confounded taxonomic classifications. A highly resolved molecular phylogeny with divergence dates for all living cat species, derived from autosomal, X-linked, Y-linked, and mitochondrial gene segments (22,789 base pairs) and 16 fossil calibrations define eight principal lineages produced through at least 10 intercontinental migrations facilitated by sea-level fluctuations. A ghost lineage analysis indicates that available felid fossils underestimate (i.e., unrepresented basal branch length) first occurrence by an average of 76%, revealing a low representation of felid lineages in paleontological remains. The phylogenetic performance of distinct gene classes showed that Y-chromosome segments are appreciably more informative than mitochondrial DNA, X-linked, or autosomal genes in resolving the rapid Felidae species radiation.

Fecal DNA Analysis for Identifying Species and Sex of Sympatric Carnivores: A Noninvasive Method for Conservation on the Tsushima Islands, Japan

Fecal analysis is a useful tool for the investigation of food habits and species identity in mammals. However, it is generally difficult to identify the species based on the morphological features and contents of feces deposited by mammals of similar body size. Therefore we developed noninvasive DNA analysis methods using fecal samples for identification of the species and sex of four small sympatric carnivores living on the Tsushima Islands of Japan: the leopard cat (Felis bengalensis), Japanese marten (Martes melampus), Siberian weasel (Mustela sibirica), and feral cat (Felis catus). Based on DNA sequence data from previous phylogenetic studies, we designed species-specific primers for polymerase chain reaction (PCR) amplification of the partial mitochondrial cytochrome b gene (112-347 bp) to identify the species and primers for the partial SRY gene (135 bp) to determine the sex. Due to the adjustment of PCR conditions, those specific DNA fragments were successfully amplified and then applied for species and sex identification. Nucleotide sequences obtained from the PCR products corresponded with cytochrome b sequences of the carnivore species expected. The protocol developed could be a valuable tool in the management and conservation of the four carnivore species occurring on the Tsushima Islands.

Genetic diversity in domestic cats Felis catus of the Tsushima Islands, based on mitochondrial DNA cytochrome b and control region nucleotide sequences

Nucleotide sequences of mitochondrial DNA (mtDNA) of 50 domestic cats (Felis catus) obtained from the Tsushima Islands were determined and the genetic diversity was analyzed. In the cats, six haplotypes of the complete cytochrome b sequences (1,140 base-pairs, bp) and ten haplotypes of the partial control region sequences (350 bp) were identified. Haplotypes obtained from both genes showed existence of at least 11 maternal lineages of domestic cats in Tsushima. Mean values of polymorphic site numbers and sequences differences in the control region were 2.4 times and 1.8 times higher than those in the cytochrome b gene, respectively. Our results support the idea that the evolutionary rate of the control region was faster than that of the cytochrome b as reported in other mammals. Molecular phylogenetic trees showed the similar clustering of haplotypes for both genes. Meanwhile, no individual variations within the Tsushima leopard cat (Felis bengalensis euptilura), which is native to Tsushima, were observed, possibly as a result of genetic drift in the small ancestral population by geographical isolation. In contrast, the diversity of the domestic cat population was higher than that of the leopard cats, because the genetic variability of the former's founders, which were repeatedly brought to Tsushima in the past, still remains. In addition, no sequences of the leopard cat mtDNA were detected in any domestic cats. However, because the possibility that the domestic cat would crossbreed with the leopard cat cannot be denied, genetic monitoring of two species is necessary to biological conservation in Tsushima.