Detection and genetic characterization of tick-borne encephalitis virus (TBEV) derived from ticks removed from red foxes (Vulpes vulpes) and isolated from spleen samples of red deer (Cervus elaphus) in Croatia.

Tick-borne encephalitis (TBE) is a growing public health concern in central and northern European countries. Even though TBE is a notifiable disease in Croatia, there is a significant lack of information in regard to vector tick identification, distribution as well as TBE virus prevalence in ticks or animals. The aim of our study was to identify and to investigate the viral prevalence of TBE virus in ticks removed from red fox (Vulpes vulpes) carcasses hunted in endemic areas in northern Croatia and to gain a better insight in the role of wild ungulates, especially red deer (Cervus elaphus) in the maintenance of the TBE virus in the natural cycle. We identified 5 tick species (Ixodes ricinus, Ixodes hexagonus, Haemaphysalis punctata, Dermacentor reticulatus, Rhipicephalus sanguineus) removed from 40 red foxes. However, TBE virus was isolated only from adult I. ricinus and I. hexagonus ticks showing a viral prevalence (1.6%) similar to or higher than reported in endemic areas of other European countries. Furthermore, 2 positive spleen samples from 182 red deer (1.1%) were found. Croatian TBE virus isolates were genetically analyzed, and they were shown to be closely related, all belonging to the European TBE virus subgroup. However, on the basis of nucleotide and amino acid sequence analysis, 2 clusters were identified. Our results show that further investigation is needed to understand the clustering of isolates and to identify the most common TBE virus reservoir hosts in Croatia. Sentinel surveys based on wild animal species would give a better insight in defining TBE virus-endemic and possible risk areas in Croatia.

Repetitive sequences in Eurasian lynx (Lynx lynx L.) mitochondrial DNA control region.

Mitochondrial DNA (mtDNA) control region (CR) of numerous species is known to include up to five different repetitive sequences (RS1-RS5) that are found at various locations, involving motifs of different length and extensive length heteroplasmy. Two repetitive sequences (RS2 and RS3) on opposite sides of mtDNA central conserved region have been described in domestic cat (Felis catus) and some other felid species. However, the presence of repetitive sequence RS3 has not been detected in Eurasian lynx (Lynx lynx) yet. We analyzed mtDNA CR of 35 Eurasian lynx (L. lynx L.) samples to characterize repetitive sequences and to compare them with those found in other felid species. We confirmed the presence of 80 base pairs (bp) repetitive sequence (RS2) at the 5' end of the Eurasian lynx mtDNA CR L strand and for the first time we described RS3 repetitive sequence at its 3' end, consisting of an array of tandem repeats five to ten bp long. We found that felid species share similar RS3 repetitive pattern and fundamental repeat motif TACAC.

Prevalence of mandibular osteomyelitis in roe deer (Capreolus capreolus) in Slovenia.

Mandibular osteomyelitis in free-ranging cervids is a rare, but eventually fatal, disease. We examined 41,895 defleshed mandibles of roe deer collected throughout Slovenia in 2007. Mandibles from 14,679 fawns had no signs of osteomyelitis, and were excluded from further analysis. Of the remaining 27,216 specimens, chronic osteomyelitis ("lumpy jaw") was found in 113 mandibles (4.2%; 7.0% of adults). The majority of cases were observed from the Mediterranean and subalpine regions, near larger cities and thermal power plants. There was no statistically significant correlation between severity of the mandibular osteomyelitis and body weight. Females were more frequently affected than males. Coarse and abrasive food, and to some extent dental fluorosis, are the most probable triggers for development of lesions.

Concentrations of trace elements in tissues of red fox (Vulpes vulpes) and stone marten (Martes foina) from suburban and rural areas in Croatia.

Trace elements concentrations (As, Cd, Cu, Pb and Hg) were determined in the liver, kidney and muscle of 28 red fox (Vulpes vulpes) and 16 stone marten (Martes foina) from suburban and rural habitats from Croatia. Rural and suburban habitats affected Cd and Hg levels in the muscle, liver and kidney of red fox. Significant differences in metal concentrations in the muscle, liver and kidney were detected among species. Suburban stone marten accumulated the highest levels of trace elements (mg/kg w.w.): in muscle 0.019 for Hg; in liver 0.161 for Cd, 36.1 for Cu and 0.349 for Pb; in kidney 1.34 for Cd and 0.318 for Pb. Values observed were higher than those found in suburban red fox and therefore, may represent an important bioindicator for the accumulation of toxic metals in urbanized habitats.

Serologic evidence of Leptospira spp. serovars in brown bears (Ursus arctos) from Croatia.

Serum samples from 52 free-ranging brown bears (Ursus arctos) collected in Croatia over a period of 10 yr (1998-2007) were tested by microscopic agglutination test for specific antibodies (Ab) to 12 Leptospira spp. pathogenic serovars. At titers ranging from 1:100 to 1:2,000, 19 samples (36.5%) were Abpositive to at least one serovar. Antibodies for 10 Leptospira spp. serovars were detected: Icterohaemorrhagiae, Australis, Sejroe, Canicola, Poi, Hardjo, Ballum, Saxkoebing, Pomona, and Grippotyphosa. In comparison to previous reports, the prevalence of Ab to serovar Icterohaemorrhagiae (52.6%) was significantly higher. Other common serovars were Australis (47.4%) and Sejroe (42.1%). High Ab titers for serovars Canicola (1:500) and Grippotyphosa (1:1,000) were detected for the first time in free-ranging bears from Croatia. A significant correlation between the age of the bears and detection of Ab to Leptospira spp. serovars suggested the presence of pathogenic agents in the natural habitats, whereas increasing trends of Ab prevalence for specific serovars (Icter-ohaemorrhagiae, Australis, and Sejroe) confirmed cohabitation of bears with rats and other small terrestrial mammals on garbage dumps and at bear feeding stations. To prevent cohabitation of bears and rodents, improvements in Croatian waste treatment, big game management, and rodent control programs are strongly recommended, especially in Lika and Gorski Kotar, regions that have high-quality natural habitats for brown bears in Croatia.

An outbreak of tick paralysis in free-ranging mouflon (Ovis ammon musimon).

During November 2006, two live and one dead mouflon (Ovis ammon musimon) were presented with a history of weakness, tremors, and paralysis. After a detailed gross and histologic examination and a bacteriologic, parasitologic, and rabies evaluation, a preliminary diagnosis of tick paralysis was established. A thorough field search revealed 13 affected mouflons found in the open hunting ground "Sveti Juraj" near the town of Senj (Croatia), along with an additional 35 mouflon carcasses. All 13 mouflons were placed in a quiet, semidark stable. All detectable ticks were removed manually, and the animals were topically treated with 250 ppm of Amitraz water emulsion (Taktic 12.5% EC, Intervet International, 5830 Boxmeer, Netherlands). The collected ticks were identified as Ixodes ricinus, Dermacentor marginatus, and Haemaphysalis punctata. In the following 24 hr, all treated animals recovered fully. This report describes a naturally occurring outbreak of tick paralysis in free-ranging mouflons from a karst habitat.

Malformation of the permanent maxillary canine after dental infraction in a wild boar (Sus scrofa L.).

Intra-alveolar infraction and malformation of the apical part of the permanent left maxillary canine in an adult male wild boar (Sus scrofa L.) is documented. The infraction and its sequelae produced an irregular mass of reparative tissue that led to the formation of two growing ends of the tooth.

Comparative morphology of incisor enamel and dentin in humans and fat dormice (Glis glis).

The structure of teeth in all living beings is genetically predetermined, although it can change under external physiological and pathological factors. The author's hypothesis was to indicate evolutional shifts resulting from genetic, functional and other differences. A comparative study about certain characteristics of incisors in humans and myomorpha, the fat dormouse (Glis glis) being their representative as well, comprised measurements of enamel and dentin thickness in individual incisor segments, evaluation of external enamel index, and also assessment of histological structure of enamel and dentin. The study results involving dormice showed the enamel to be thicker in lower than in the upper teeth, quite contrary to enamel thickness in humans. In the upper incisors in dormice the enamel is the thickest in the medial layer of the crown, and in the cervical portion of the crown in the lower incisors. The thickness of dentin in dormice is greater in the oral than in the vestibular side. These findings significantly differ from those reported in reference literature, but they are based on the function of teeth in dormice. Histological characteristics of hard dental tissues in dormice are similar to those in humans, with exception of uniserial structure of enamel and appearance of dentinoenamel junction.