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Pinnipeds are a diverse Glade of semi-aquatic mammals, which act as key indicators of ecosystem health. Their transition from land to marine environments provides a complex microbial milieu, making them vulnerable to both aquatic and terrestrial pathogens, thereby contributing to pinniped population decline. Indeed, viral pathogens such as influenza A virus and phocine distemper virus (PDV) have been identified as the cause of several of these mass mortality events. Furthermore, bacterial infection with mammalian Brucella sp. and methicillin-resistant Staphylococcus aureus strains have also been observed in marine mammals, posing further risk to both co-habiting endangered species and public health. During these disease outbreaks, mortality rates have varied amongst different pinniped species. Analyses of innate immune receptors at the host pathogen interface have previously identified variants which may drive these species-specific responses. Through a combination of both sequence- and structure-based methods, this study characterises members of the Toll-like receptor (TLR) 1 superfamily from both harbour and elephant seals, identifying variations which will help us to understand these species-specific innate immune responses, potentially aiding the development of specific vaccine-adjuvants for these species. (C) 2015 Elsevier B.V. All rights reserved.

Nine eastern black rhinoceroses (Diceros bicornis michaeli) developed clinical clostridial enterotoxaemia between May and July 2010 in the Pyramid Black Rhino Sanctuary within the Ol Jogi Conservancy, Laikipia, Kenya. The rhinos presented with a peracute syndrome characterised by severe abdominal pain manifested by struggling and rolling on the ground, laboured breathing and died within three hours after being sighted sick. Necropsy and histopathology revealed severe pathology in the gastro-intestinal tract (GIT). Grossly, the small and large intestines were congested and oedematous. All the rhinos had variable amounts of hemorrhagic fluid in the intestines. Microscopically, the most characteristic lesion was severe necrotising-haemorrhagic enteritis. Numerous gram-positive rod-shaped bacterial colonies that were identified to be Clostridium spp were occasionally seen in the intestinal mucosa. Clostridium perfringens type A was isolated from the stomach contents. C. perfringens was postulated as the aetiological agent with the infection triggered probably by change of habitat following a prolonged period of drought that was followed by above normal rainfall.

Nine eastern black rhinoceroses (Diceros bicornis michaeli) developed clinical clostridial enterotoxaemia between May and July 2010 in the Pyramid Black Rhino Sanctuary within the Ol Jogi Conservancy, Laikipia, Kenya. The rhinos presented with a peracute syndrome characterised by severe abdominal pain manifested by struggling and rolling on the ground, laboured breathing and died within three hours after being sighted sick. Necropsy and histopathology revealed severe pathology in the gastro-intestinal tract (GIT). Grossly, the small and large intestines were congested and oedematous. All the rhinos had variable amounts of hemorrhagic fluid in the intestines. Microscopically, the most characteristic lesion was severe necrotising-haemorrhagic enteritis. Numerous gram-positive rod-shaped bacterial colonies that were identified to be Clostridium spp were occasionally seen in the intestinal mucosa. Clostridium perfringens type A was isolated from the stomach contents. C. perfringens was postulated as the aetiological agent with the infection triggered probably by change of habitat following a prolonged period of drought that was followed by above normal rainfall.

Enterohemorrhagic Escherichia coli (EHEC) strains are a subset of Shiga toxin (Stx)-producing E. coli (STEC) strains that are isolated from human patients and are responsible for severe clinical symptoms, such as hemorrhagic colitis (HC) and the potentially lethal hemolytic uremic syndrome (HUS) (28, 29). Although most outbreaks of HC and HUS have been attributed to serotype O157:H7/H−, an increasing number of human infections are caused by other serotypes, such as O26:H11/H−, O103:H2, O111:H8/H−, and O145:H28/H− (13, 20, 28). O157:H7/H− and these four serotypes were classified into seropathotypes A and B, respectively, which occur most frequently in human diseases and outbreaks and in patients with severe symptoms (30). Shiga toxins, the main virulence factors contributing to pathogenicity, consist of two major types, Stx1 and Stx2, each including several variants (47). In addition to Stx, typical EHEC strains carry on their chromosomes the locus for enterocyte effacement (LEE), a large pathogenicity island that is shared with enteropathogenic E. coli (EPEC). The LEE is responsible for attaching and effacing (A/E) lesions on enterocytes (34); it encodes several virulence factors, including the outer membrane adhesin intimin and its translocated receptor Tir, as well as components of a type III secretion machinery and its effector proteins. Intimin is involved in the tight attachment of bacteria to the enterocytes. It is encoded by the eae gene, 18 types and 9 subtypes of which have been described on the basis of its variable 3′ region (25). The EHEC serotypes O157:H7 and O145:H28 are known to be associated with the eae-γ1 subtype, whereas EHEC O26:H11, O103:H2, and O111:H8 harbor the eae-β1, eae-ɛ, and eae-γ2/θ subtypes, respectively (7, 11, 37, 51). Additional candidate pathogenicity islands, or “O islands” (OI), that may contribute to virulence have been identified. They include OI-71 and OI-122, which contain a number of type III non-LEE-encoded effector (nle) genes whose presence correlates with outbreak and HUS potential (17). Finally, EHEC O157:H7 contains a large plasmid with putative virulence genes encoding the EHEC-hemolysin (EHEC-hlyA), a serine protease (espP), and a catalase peroxidase (katP). However, strains lacking one or more of these genes have been involved in HUS, and high variability in the gene composition of this large plasmid has also been reported in various STEC serotypes (14). Domestic ruminants have long been identified as a major reservoir for STEC (29). Although STEC transmission to humans is frequently associated with consumption of raw or undercooked meat, raw milk and dairy products have also been implicated in human disease (4). Detection and isolation of STEC in foodstuffs by traditional culture methods is rather laborious and time-consuming and is complicated by the lack of common biochemical characteristics distinguishing most STEC from other E. coli strains. Development of rapid methods for the detection of the most pathogenic STEC strains is essential to ensure the safety of food products. A sequential approach based on real-time PCR assays specific for stx, wzxO26, wzxO103, wbdIO111, ihp1O145, and rfbEO157 genetic markers has been described for the detection of STEC O26, O103, O111, O145, and O157 in foods (3, 40). A similar strategy that includes an additional eae amplification step has been proposed by working group 6 of the European Committee for Standardization (CEN) TC275 for a technical specification (currently under International Organization for Standardization [ISO] evaluation) regarding the detection of these five STEC serogroups in foods (21). Recently, we developed real-time PCR assays for detection of the eae variants and fliC alleles associated with the five most common EHEC serotypes (32). The aim of the present study was to investigate whether these newly developed assays could further refine the diagnostic result obtained from PCR analysis of foods. To this end, the prevalence of stx, O group genetic markers, eae variants, and fliC alleles typical of EHEC O26:H11, O103:H2, O111:H8, O145:H28, and O157:H7 was investigated in 400 raw-milk cheeses. STEC and E. coli strains belonging to the five targeted serotypes were then isolated for confirmation of the PCR results, and their virulence traits were characterized. As the term EHEC includes a clinical connotation (28, 29), the stx-positive E. coli isolates recovered from food are designated STEC (not EHEC) here, irrespective of the serotype.

Depredation by wolves (Canis lupus) could threaten survival of reintroduced wild Przewalski horses (Equus ferus przewalskii) in Hustai National Park (HNP), Mongolia. We conducted scat analysis, spatial analyses of kills, and interviews to study prey species selection and temporal and spatial factors that characterize prey choices of wolves. Diet of wolves in HNP was comprised of >50% of livestock. Diet composition varied during the year, with more livestock taken in winter. Wildlife species were selected over livestock species. From available livestock species domestic horses were predated most, whereas red deer (Cervus elaphus) and marmot (Marmota sibirica) were the preferred wildlife species. Our spatial analyses showed an unexpected significant positive relation between number of domestic horses killed and distance to the park, as well as a significant negative relation with number of gers (tents) in the area. Compared to randomly selected comparison sites (n = 36), we found Przewalski foal kills (n = 36) at sites that were closer to the forest, at higher altitudes, with lower shrub cover, higher forest cover, and higher red deer density. If the negative trend of deer numbers continues and if herdsmen protect their livestock more vigorously, depredation of wild Przewalski horses by wolves will rise. Therefore, a large red deer population could be pivotal in improving the conservation status of Przewalski horses

Taenia asiatica has made a remarkable journey through the scientific literature of the past 50 years, starting with the paradoxical observation of high prevalences of T. saginata-like tapeworms in non-beef consuming populations, to the full description of its mitochondrial genome. Experimental studies conducted in the 1980s and 1990s have made it clear that the life cycle of T. asiatica is comparable to that of T. saginata, except for pigs being the preferential intermediate host and liver the preferential location of the cysts. Whether or not T. asiatica can cause human cysticercosis, as is the case for Taenia solium, remains unclear. Given the specific conditions needed to complete its life cycle, in particular the consumption of raw or poorly cooked pig liver, the transmission of T. asiatica shows an important ethno-geographical association. So far, T. asiatica has been identified in Taiwan, South Korea, Indonesia, the Philippines, Thailand, south-central China, Vietnam, Japan and Nepal. Especially this last observation indicates that its distribution is not restricted to South-East-Asia, as was thought so far. Indeed, the molecular tools developed over the last 20 years have made it increasingly possible to differentiate T. asiatica from other taeniids. Such tools also indicated that T. asiatica is related more closely to T. saginata than to T. solium, feeding the debate on its taxonomic status as a separate species versus a subspecies of T. saginata. Furthermore, the genetic diversity within T. asiatica appears to be very minimal, indicating that this parasite may be on the verge of extinction. However, recent studies have identified potential hybrids between T. asiatica and T. saginata, reopening the debate on the genetic diversity of T. asiatica and its status as a separate species.