Acute disseminated toxoplasmosis in a red fox (Vulpes vulpes)

A red fox (Vulpes vulpes) with signs of neurological disease was captured in Fairmount Park, Philadelphia, Pennsylvania (USA). The animal died in captivity and was examined because of suspected rabies. The liver had pale foci up to 4 mm in diameter. Foci of necrosis were associated with Toxoplasma gondii tachyzoites in several organs including liver, lungs and adrenal glands. Rabies antigen and distemper virus inclusions were not detected. The diagnosis of acute disseminated toxoplasmosis was confirmed by immunohistochemical staining.     

Identification of the Tibetan fox (Vulpes ferrilata) and the red fox (Vulpes vulpes) by copro-DNA diagnosis

Studies on feeding habits based on faeces dissecting are imperative to understand the natural history of Tibetan foxes and their functions in the transmission of a lethal zoonotic parasite, Echinococcus multilocularis. However, Tibetan foxes and red foxes live sympatrically on the Tibetan plateau, China. Therefore, the faeces of Tibetan foxes must be distinguished from those of red foxes. We established a diagnostic method to distinguish the faeces of the two species by amplifying a portion of the mitochondrial cytochrome b gene (cytb) and digesting with the restriction enzymes BamHI and SspI, to produce specific diagnostic banding patterns. This PCR-RFLP assay enabled rapid, accurate and easily performed identification and differentiation of the two species.     

Variations of the chromosome number in the red fox (Vulpes vulpes)

The chromosome number in peripheral blood cells of five individuals of Vulpes vulpes (Red Fox) is shown to vary between 35 and 39. This variation is due to loss or gain of the smallest autosome, which it is suggested is heterochromatic and does not have any major influence on the phenotype. This species demonstrates variation in chromosome number both between and within individuals.     

Mitochondrial DNA phylogeography of the red fox (Vulpes vulpes) in northern Japan

Mitochondrial DNA variation in the cytochrome b (cyt b) gene and the control region was examined in the red fox Vulpes vulpes from Japan, with special focus on the population divergence between Hokkaido and northern Honshu. Resultant haplotypes from Hokkaido were subdivided into two distinct groups (I and II), with an average genetic distance of 0.027 for cyt b. Divergence time is roughly estimated to be 1-2 million years ago, given that the conventional divergence rate of the mammalian cyt b gene is 2% per million years. Notably, Group II was only found in Hokkaido, whereas Group I comprised haplotypes from Honshu, Kyushu (Japan), eastern Russia, and Europe, as indicated by a comparison of our own data to the literature. On the other hand, judging from constructed trees, Group I haplotypes from Hokkaido appeared to differ from those from other parts of Japan, i.e., Honshu and Kyushu. This implies that Blakiston's Line, which demarcates the boundary between Hokkaido and Honshu, has been an effective barrier and has allowed the structuring of genetic variation in maternal lineages. Thus, these results suggest that the Hokkaido population, which is sometimes referred to as the distinct subspecies V. v. schrencki, has its own genetic background with multiple migration events and differs from the parapatric subspecies V. v. japonica found in Honshu and Kyushu.     

The flea epifauna of a suburban fox (Vulpes vulpes) population

Five hundred and thirteen fleas, of eight different species, were collected from a sample of 252 foxes killed in suburban London. 25–8% of foxes carried fleas, with a mean of 204 fleas per fox. Levels of infestation of male and female hosts did not differ significantly. Possible sources of the fleas infesting foxes are discussed with respect to their seasonal occurrence and fox prey composition. No evidence was found to support the suggestion that foxes obtain the majority of their fleas from prey items, although occasional heavy infestations of some flea species were probably derived from recent meals. Although Pulex irritans, Paraceras m. melis and Ctenocephalides canis , which contributed 35 % of the flea epifauna, could be considered parasitic on the fox, it seems probable that foxes pick up the majority of their fleas from the habitat through which they move. Thus, two particularly heavily infested categories of foxes were found: (1) juveniles during July-September, their fleas probably being accumulated during exploratory and play activities, and (2) all animals during the period October-December.     

LHRH and LH release in the red fox Vulpes vulpes L

Pituitary responsiveness to exogenous LHRH was studied in vivo and in vitro in the female red fox, a mono-oestrous species. In vivo, the ability of the pituitary to release LH in response to a single injection of LHRH (2 micrograms/kg) was determined at various stages of the reproductive cycle. The greatest responsiveness is observed during the preovulatory period, the lowest during the luteal phase. During the anoestrus phase, the responsiveness is reduced by more than 50% in lactating females compared to non lactating females. In vitro, dispersed fox anterior pituitary cells were exposed four times to LHRH (10(-9) M), hourly, for 8 min. Pituitary cells were taken from lactating and non lactating females. The cells are not sensitive to LHRH in lactating females but become more and more sensitive after weaning. It is suggested the inhibitory influence of lactation could be the result of prolactin-ovarian steroids-gonadotrophins interactions.     

Complete mitochondiral genome of the Korean red fox Vulpes vulpes (Carnivora, Canidae)

The complete mitochondrial genome sequence of Vulpes vulpes consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 control region (CR). CR is located between the tRNA-Pro and tRNA-Phe genes and is 1173?base pairs (bp) in length. It consists of a short non-repetitive sequence followed by 8-bp 5'-ACACACGT-3' tandem repeat between conserved sequence black I and conserved sequence black II.     

Disseminated bovine tuberculosis in a wild red fox (Vulpes vulpes) in southern Spain

A wild-caught, adult red fox (Vulpes vulpes) from Do?ana National Park (southern Spain), in very poor condition, died during anesthesia. At necropsy, the submandibular, retropharyngeal, mediastinal, axillary, mesenteric, and popliteal lymph nodes were enlarged, and the right submandibular and mesenteric lymph nodes had hard, white-colored concretions (calcifications). Multiple white pinpoint foci were observed in the lungs, and abscesses were present in the left dorsal lung lobes. No lesions were seen in tonsils, liver, or spleen. On histopathology multiple tuberculous granulomas, with Ziehl-Neelsen-positive bacilli, were observed in the lung, and multifocal necrotic areas with calcification were present in the submandibular and mesenteric lymph nodes. Nucleic acid amplification from lymph node samples demonstrated the presence of mycobacteria belonging to the Mycobacterium tuberculosis complex. One strain was isolated by culture and identified as Mycobacterium bovis. The suspected route of infection was oral, probably after repeated scavenging of infected wild ungulate carcasses. This is the first report of generalized bovine tuberculosis (bTB) in a wild canid. This finding raises concerns about bTB as a disease risk for protected species, livestock, and humans in Mediterranean Spain.     

High genetic diversity and low population structure in red foxes (Vulpes vulpes) from Croatia

The red fox (Vulpes vulpes) is a highly adaptable omnivorous mammal distributed across all continents on the northern hemisphere. Although the red fox is present throughout Europe, where it plays an important ecological and socio-economic role not only as a game species but also as a rabies reservoir, few studies have examined its population-level mitochondrial DNA variability. In this study, 27 mitochondrial DNA control region haplotypes were identified in 229 red fox samples taken from four regions in Croatia. Haplotype diversity of Croatian red foxes (0.901) was found to be among the highest of all European red fox populations studied to date. Genetic differentiation among regions was quite low, and statistically significant estimates of differentiation were obtained only when comparing the population from the peninsular region of Istria with the three continental populations. It seems that landscape barriers like rivers and small mountains do not restrict gene flow among foxes in the continental part of Croatia, while the combination of a narrow land bridge and altitudes exceeding 1000 m limit fox migration between Istria and the rest of the continent. Better understanding of small-scale population structure will require analysis of highly variable nuclear markers like microsatellites.     

Microevolutionary trends in the dentition of the Red fox (Vulpes vulpes)

Microevolutionary trends in dental traits were studied in a Polish population of the Red fox, Vulpes vulpes (Linnaeus, 1758). Changes in qualitative and quantitative traits over a 70‐year interval were analysed in 1453 museum specimens collected between 1927 and 1996. Over that period, there were qualitative trends towards increasing complication of occlusal crown surface in posterior premolars (i.e. P⁴, P₃, P₄) and I³. Other cheek teeth did not undergo directional change. Changes in trait correlations were assessed using samples from the 1960s and 1990s. The correlations between C¹–C₁ and M¹–M² increased, while correlation values in the incisor region (I₁–I₂, I¹–I₁, I¹–I₂, I³–I₂), carnassial region (P₄–M₁, P⁴–M₁ and M₁–M₁) and in P²–P₁ decreased. These changes may be related to increasing dietary opportunism of the Red fox during the 20th century.