Implications for human-wolf conflict due to free-roaming domestic dogs predation on deer in southern Spain:

Duarte, J., García, F. J., & Fa, J. E. (2016). Depredatory impact of free-roaming domestic dogs on Mediterranean deer in southern Spain: implications for human-wolf conflict. Folia Zoologica, 65(2).

Feral domestic dogs are efficient wild ungulate hunters in many parts of the world. This has not been confirmed in Mediterranean ecosystems. However, if feral dogs can predate upon wild Mediterranean ungulates, they can also do so upon livestock. Therefore, to more realistically understand human-wolf conflict in areas where wolves and feral dogs overlap, the possible role of the latter taking domestic prey should be considered. During a 6-month study period, we carried out daily observations of a pack of mediumsized dogs, where they were the only large-bodied carnivore capable of killing ungulates in a fenced estate in southern Spain. The estate contained sizeable populations of red deer, fallow deer and mouflons, but no livestock. We described feral dog predation patterns and depredatory impact. We found that dogs predated upon a total of 57 ungulates; fallow deer (47 %), red deer (37 %), and mouflon (16 %). Red deer adults were the least frequent prey, but dogs killed significantly more females and fawns of red and fallow deer. Mouflons were attacked indistinctly. Our results suggest that dogs in our study exhibited a kill pattern similar to Iberian wolves. Therefore, in areas where wolves and feral dogs coexist, a significant proportion of livestock predation could be falsely attributed to the wild canid. In addition, the presence of feral dogs may be a cause of risk in big game hunting estates.

Cross-species transmission of CDV

Beineke, A., Baumgärtner, W. & Wohlsein, P. 2015. Cross-species transmission of canine distemper virus-an update. One Health 1, 49–59.

Canine distemper virus (CDV) is a pantropic morbillivirus with a worldwide distribution, which causes fatal disease in dogs. Affected animals develop dyspnea, diarrhea, neurological signs and profound immunosuppression. Systemic CDV infection, resembling distemper in domestic dogs, can be found also in wild canids (e.g. wolves, foxes), procyonids (e.g. raccoons, kinkajous), ailurids (e.g. red pandas), ursids (e.g. black bears, giant pandas), mustelids (e.g. ferrets, minks), viverrids (e.g. civets, genets), hyaenids (e.g. spotted hyenas), and large felids (e.g. lions, tigers). Furthermore, besides infection with the closely related phocine distemper virus, seals can become infected by CDV. In some CDV outbreaks including the mass mortalities among Baikal and Caspian seals and large felids in the Serengeti Park, terrestrial carnivores including dogs and wolves have been suspected as vectors for the infectious agent. In addition, lethal infections have been described in non-carnivore species such as peccaries and non-human primates demonstrating the remarkable ability of the pathogen to cross species barriers. Mutations affecting the CDV H protein required for virus attachment to host-cell receptors are associated with virulence and disease emergence in novel host species. The broad and expanding host range of CDV and its maintenance within wildlife reservoir hosts considerably hampers disease eradication.

Potential transmision of dog pathogens to wild carnivores in India

Chaudhary, V. (2016). Threats of Disease Spillover from Domestic Dogs to Wild Carnivores in the Kanha Tiger Reserve, India. MSc disertation  Graduate School of Clemson University.

Many mammalian carnivore species persist in small, isolated populations as a result of habitat destruction, fragmentation, poaching, and human conflict. Their small numbers, limited genetic variability, and increased exposure to domestic animals such as dogs place them at risk of further losses due to infectious diseases. In India, dogs ranging from domestic to feral are associated with villages in and around protected areas, and may serve as reservoirs and vectors of pathogens to the carnivores within. India’s Kanha Tiger Reserve (KTR) is home to a number of threatened and endangered mammalian carnivores including tigers (Panthera tigris), leopards (Panthera pardus), wolves (Canis lupus), and dhole (Cuon alpinus). It also contains hundreds of small villages with associated dog populations, and my goal was to determine whether these dogs pose a disease threat to KTR’s wild carnivores. In the summer of 2014 and again in the winter of 2015 I estimated the density of dogs in villages of varying sizes and distances from KTR’s core zone, and the exposure of these dogs to four pathogens that could threaten wild carnivores: rabies, canine parvovirus (CPV), canine distemper (CDV), and canine adenovirus (CAV). Dog population densities ranged from 3.7 to 23.7/km²(14 to 45 dogs/village), and showed no systematic variation with village area or human population size. These dog populations grew in all villages between the summer of 2014 and winter of 2015, primarily through reproduction. No dog tested positive for rabies but I found high levels of seroprevalence to the other three pathogens: CPV (83.6% in summer 2014,
68.4% in winter 2015), CDV (50.7% in summer 2014, 30.4% in winter 2015) and CAV (41.8% in summer 2014, 30.9% in winter 2015). The declines in seroprevalence between summer and winter were primarily due to births in the population, of animals not exposed to the viruses. I opportunistically documented interactions between the dogs and wild carnivores that might allow disease transmission. I measured these interactions as the presence of wild carnivores in surveyed villages. In this study I document the existence of a large population of unvaccinated dogs in and around KTR, with high levels of seroprevalence to pathogens with broad host ranges. These dogs also have frequent contact with wild carnivores. I conclude that these dogs pose a high risk of disease spillover to wild carnivores in the region.
I also tested for CPV and CDV in wild carnivore samples obtained from the KTR Forest Department from 2010 to 2015. While one tiger blood sample was seropositive for CPV antibodies, the reverse transcriptase polymerase chain reaction found no evidence of CPV in tissue samples from five tigers, one leopard and one palm civet (Paradoxurus hermaphroditus), and no CPV or CDV in the three blood samples of tigers. Despite these results, I argue for continued surveillance in KTR, given the ubiquity of village dogs in the area with high seroprevalence of CDV and CPV and the contact between dogs and endangered carnivores in KTR. 

Domestic dogs are the only population essential for persistence of rabies in Serengeti

Lembo, T., Hampson, K., Haydon, D. T., Craft, M., Dobson, A., Dushoff, J., ... & Mentzel, C. (2008). Exploring reservoir dynamics: a case study of rabies in the Serengeti ecosystem. Journal of Applied Ecology, 45(4), 1246-1257.

1. Knowledge of infection reservoir dynamics is critical for effective disease control, but identifying reservoirs of multi-host pathogens is challenging. Here, we synthesize several lines of evidence to investigate rabies reservoirs in complex carnivore communities of the Serengeti ecological region in northwest Tanzania, where the disease has been confirmed in 12 carnivore species.
2. Long-term monitoring data suggest that rabies persists in high-density domestic dog Canis familiaris populations (> 11 dogs/km²) and occurs less frequently in lower-density (< 5 dogs /km²) populations and only sporadically in wild carnivores.
3. Genetic data show that a single rabies virus variant belonging to the group of southern Africa canid-associated viruses (Africa 1b) circulates among a range of species, with no evidence of species-specific virus–host associations.
4. Within-species transmission was more frequently inferred from high-resolution epidemiological data than between-species transmission. Incidence patterns indicate that spill-over of rabies from domestic dog populations sometimes initiates short-lived chains of transmission in other carnivores.
5. Synthesis and applications. The balance of evidence suggests that the reservoir of rabies in the Serengeti ecosystem is a complex multi-host community where domestic dogs are the only population essential for persistence, although other carnivores contribute to the reservoir as non-maintenance populations. Control programmes that target domestic dog populations should therefore have the greatest impact on reducing the risk of infection in all other species including humans, livestock and endangered wildlife populations, but transmission in other species may increase the level of vaccination coverage in domestic dog populations necessary to eliminate rabies.

Vulture declines and increased dog scavenging

Ogada, D. L., Torchin, M. E., Kinnaird, M. F., & Ezenwa, V. O. (2012). Effects of vulture declines on facultative scavengers and potential implications for mammalian disease transmission. Conservation Biology, 26(3), 453-460.

Vultures (Accipitridae and Cathartidae) are the only known obligate scavengers. They feed on rotting carcasses and are the most threatened avian functional group in the world. Possible effects of vulture declines include longer persistence of carcasses and increasing abundance of and contact between facultative scavengers at these carcasses. These changes could increase rates of transmission of infectious diseases, with carcasses serving as hubs of infection. To evaluate these possibilities, we conducted a series of observations and experimental tests of the effects of vulture extirpation on decomposition rates of livestock carcasses and mammalian scavengers in Kenya. We examined whether the absence of vultures changed carcass decomposition time, number of mammalian scavengers visiting carcasses, time spent by mammals at carcasses, and potential for disease transmission at carcasses (measured by changes in intraspecific contact rates). In the absence of vultures, mean carcass decomposition rates nearly tripled. Furthermore, the mean number of mammals at carcasses increased 3-fold (from 1.5 to 4.4 individuals/carcass), and the average time spent by mammals at carcasses increased almost 3-fold (from 55 min to 143 min). There was a nearly 3-fold increase in the mean number of contacts between mammalian scavengers at carcasses without vultures. These results highlight the role of vultures in carcass decomposition and level of contact among mammalian scavengers. In combination, our findings lead us to hypothesize that changes in vulture abundance may affect patterns of disease transmission among mammalian carnivores.

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Los buitres (Accipitridae y Cathartidae) son los únicos carroñeros obligados que se conocen. Se alimentan de cadáveres en descomposición y son el grupo funcional de aves más amenazado del mundo. Los efectos posibles de las declinaciones de buitres incluyen una mayor persistencia de cadáveres y el incremento de la abundancia de y contacto entre carroñeros facultativos en esos cadáveres. Estos cambios podrían incrementar las tasas de transmisión de enfermedades infecciosas, con los cadáveres funcionando como focos de infección. Para evaluar estas posibilidades, realizamos una serie de observaciones y pruebas experimentales de los efectos de la extirpación de buitres sobre las tasas de descomposición de cadáveres de ganado y mamíferos carroñeros en Kenia. Examinamos sí la ausencia de buitres cambiaba el tiempo de descomposición de cadáveres, el número de mamíferos carroñeros visitando los cadáveres, el tiempo utilizado por mamíferos en los cadáveres y la potencial transmisión de enfermedades en los cadáveres (medida por cambios en las tasas de contacto interespecífico). En ausencia de buitres, las tasas medias de descomposición de cadáveres incrementaron 3 veces (de 1.5 a 4.4 individuos/cadáver), y el tiempo promedio invertido por mamíferos en los cadáveres incrementó casi 3 veces (de 55 min a 143 min). Hubo un aumento de casi tres veces en el número promedio de contactos entre mamíferos carroñeros en cadáveres sin buitres. Estos resultados resaltan el papel de los buitres en la descomposición de cadáveres y del nivel de contacto entre mamíferos carroñeros. En combinación, nuestros resultados nos llevaron a plantear la hipótesis de que cambios en la abundancia de buitre pueden afectar los patrones de transmisión de enfermedades entre mamíferos carnívoros.

Pathogens of domestic carnivores around a National Park

Fiorello, C. V., Deem, S. L., Gompper, M. E., & Dubovi, E. J. (2004). Seroprevalence of pathogens in domestic carnivores on the border of Madidi National Park, Bolivia. Animal Conservation, 7(1), 45-54.

The importance of diseases of domestic animals in the conservation of wildlife is increasingly being recognised. Wild carnivores are susceptible to many of the pathogens carried by domestic dogs and cats and some of these pathogens have caused disease outbreaks and severe population declines in threatened species. The risk of disease spillover from domestic to wild carnivores in South America has not been extensively investigated. This study examined the disease exposure of domestic carnivores living near a protected area in Bolivia. Forty dogs and 14 cats living in three towns on the eastern border of Madidi National Park were sampled. High levels of exposure to canine distemper virus, canine parvovirus, Sarcoptes scabiei and Toxoplasma gondii were found among domestic dogs, with similarly high levels of exposure to feline parvovirus, feline calicivirus and T. gondii being found among domestic cats. If contact occurs between domestic and wild carnivores, disease spillover may represent an important risk for the persistence of wild carnivores in the region. Additional research is therefore necessary to determine if wild carnivores living in proximity to these domestic carnivore populations are being exposed to these pathogens.

Occurrence of pathogens in Brazilian wild carnivores and its implications for conservation and public health

Jorge, R. S., Rocha, F. L., May-Júnior, A. J., & Morato, R. G. (2010). Ocorrência de patógenos em carnívoros selvagens brasileiros e suas implicações para a conservação e saúde pública. Oecologia Australis, 14(3), 686-710.

Several outbreaks caused by pathogens caused declines in wild carnivore populations in the last decades. In addition to the negative impact to wild populations, there is a concern about the transmission of some of these agents to humans and domestic animals. In fact, environmental alterations have resulted in changes in the pathogen-host relation. Therefore, monitoring health of wild animals is considered an important component in programs for control or eradication of diseases and in the public and animal health politics and for the management and conservation of wild species. Considering the role of mammals of the order Carnivora in the trophic chain, they might be used as “sentinels”, working as strategic targets in programs of surveillance of important pathogens for public and animal health. We review in this paper case-studies of the main pathogens that occur in wild carnivores, emphasizing species of the Brazilian fauna. We also discuss laboratorial methods used in studies of exposure of Brazilian wild carnivores to pathogens, as well as strategies to minimize the impacts in these populations caused by that exposure, and methods for controlling the occurrence of zoonotic pathogens in wild carnivores.


Diversos surtos epidêmicos causados por agentes patogênicos provocaram severo declínio em populações de carnívoros selvagens nas últimas décadas. Além deste impacto às populações silvestres, há a preocupação da transmissão de alguns destes agentes à população humana e de animais domésticos. De fato, as alterações ambientais têm provocado mudanças na relação patógeno-hospedeiro. Desta forma, o monitoramento da saúde de animais silvestres é importante componente no estabelecimento de programas de controle e erradicação de doenças e na elaboração de políticas de saúde pública e animal e de manejo e conservação de espécies selvagens. Considerando o papel dos mamíferos da ordem Carnivora na cadeia trófica, estes podem ser usados como “sentinelas”, sendo alvos estratégicos em programas de vigilância para detecção de patógenos. Neste artigo serão revisados estudos de caso dos principais patógenos que acometem carnívoros selvagens, com ênfase nas espécies da fauna brasileira. Os métodos laboratoriais utilizados nos estudos de exposição dos carnívoros brasileiros a patógenos serão discutidos e considerações sobre estratégias para minimizar seus impactos sobre a fauna silvestre, bem como os possíveis métodos para controle de patógenos causadores de zoonoses em carnívoros.

Pathogens of wild maned wolves in Brazil

Curi, N. H. D. A., Coelho, C. M., Malta, M. D. C. C., Magni, E. M. V., Sábato, M. A. L., Araújo, A. S., ... & Souza, S. L. P. D. (2012). Pathogens of wild maned wolves (Chrysocyon brachyurus) in Brazil. Journal of wildlife diseases, 48(4), 1052-1056.

The maned wolf, Chrysocyon brachyurus, is an endangered Neotropical canid that survives at low population densities. Diseases are a potential threat for its conservation but to date have been poorly studied. We performed clinical evaluations and investigated the presence of infectious diseases through serology and coprologic tests on maned wolves from Galheiro Natural Private Reserve, Perdizes City, Minas Gerais State, southeastern Brazil. Fifteen wolves were captured between 2003 and 2008. We found high prevalences of antibody to canine distemper virus (CDV; 13/14), canine
parvovirus (CPV; 4/14), canine adenovirus type 2 (13/14), canine coronavirus (5/11), canine parainfluenza virus (5/5), and Toxoplasma gondii (6/8), along with Ancylostomidae eggs in all feces
samples. Antibodies against Leishmania sp. were found in one of 10 maned wolves, and all samples were negative for Neospora caninum. Evidence of high exposure to these viral agents was also observed in unvaccinated domestic dogs from neighboring farms. High prevalence of viral agents and parasites such as CDV, CPV, and Ancylostomidae indicates that this population faces considerable risk of outbreaks and chronic debilitating parasites. This is the first report of exposure to canine parainfluenza virus in Neotropical free-ranging wild canids. Our findings highlight that canine pathogens pose a serious hazard to the viability of maned wolves and other wild carnivore populations in the area and emphasize the need for monitoring and protecting wildlife health in remaining fragments of the Cerrado biome.

Leishmania in wild and domestic canids around a Brazilian National Park

Curi, N. H. D. A., Miranda, I., & Talamoni, S. A. (2006). Serologic evidence of Leishmania infection in free-ranging wild and domestic canids around a Brazilian National Park. Memórias do Instituto Oswaldo Cruz, 101(1), 99-101.

Transmission of disease between wildlife, domestic animals, and humans is of great concern to conservation issues and public health. Here we report on the prevalence of anti-Leishmania sp. antibodies in 21 wild canids (7 Chrysocyon brachyurus, 12 Cerdocyon thous, and 2 Lycalopex vetulus) and 74 free domestic dogs (Canis familiaris) sampled around the Serra do Cipó National Park. In dogs, the apparent prevalence was 8.1% and in wild canids it was 19% (2 crab-eating foxes, C. thous, and 2 maned wolves, C. brachyurus). Management of the domestic dog population with evaluation of incidence changes in humans and wildlife, and enlightenment on the role of wild reservoirs are essential issues for future action and research.

Genetics of CDV in East African carnivores

Carpenter, M. A., Appel, M. J., Roelke-Parker, M. E., Munson, L., Hofer, H., East, M., & O'Brien, S. J. (1998). Genetic characterization of canine distemper virus in Serengeti carnivores. Veterinary immunology and immunopathology, 65(2), 259-266.

The lion (Panthera leo) population in the Serengeti ecosystem was recently afflicted by a fatal epidemic involving neurological disease, encephalitis and pneumonia. The cause was identified as canine distemper virus (CDV). Several other species in the Serengeti were also affected. This report presents CDV H and P gene sequences isolated from Serengeti lions (Panthera leo), spotted hyenas (Crocuta crocuta), bat-eared fox (Otocyon megalotis) and domestic dog (Canis familiaris). Sequence analyses demonstrated that the four Serengeti species carry closely related CDV isolates which are genetically distinct from other CDV isolates from various species and locations. The results are consistent with the conclusions that: (1) a particularly virulent strain of CDV emerged among Serengeti carnivores within the last few years; (2) that strain has recognizable shared-derived (synapomorphic) genetic differences in both H and P genes when compared to CDV from other parts of the world; and (3) that the CDV strain has frequently crossed host species among Serengeti carnivores.

Invasive stray and feral dogs limit endangered fossa populations in Madagascar

Barcala O. 2009. Invasive stray and feral dogs limit fosa (Cryptoprocta ferox) populations
in Ankarafantsika National Park, Madagascar. Duke University (M.Sc. thesis),
Durham, North Carolina, U.S.A. 

The fosa (Cryptoprocta ferox) is a medium sized carnivore of the family Eupleridae which is endemic to the island of Madagascar. Recent publications have shown that the fosa is under significant pressure from deforestation and fragmentation, leading to its classification as Threatened under the Endangered Species Act. A trap study was conducted from 1999 to 2008 in Ankarafantsika National Park, Madagascar, to ascertain the health of a population and measure additional threats to its survival. Feral dogs (Canis lupus familiaris) appeared in the park in 2004 and a comparison of trap rates of the two species shows an inverse relationship between the presence of dogs and the presence of fosa. In this paper I discuss reasons for this relationship, the effect of the continued presence of dogs, and implications for the management of the park.

Feral cats and dogs the most abundant carnivores in endangered Fossa habitat

Mann, G. K. H., & Hawkins, F. 2015. First record of Fossa Cryptoprocta ferox in Mariarano forest, Madagascar. Small Carnivore Conservation 52 & 53: 45–55

We surveyed the carnivore community in two patches of forest around Mariarano village in north-western Madagascar using camera traps. Cameras were set along trails in the forest and were active for a total of 517 trap nights. We recorded the presence of two indigenous carnivore species, Fossa Cryptoprocta ferox and Western Falanouc Eupleres major, and three introduced carnivore species; Small Indian Civet Viverricula indica, domestic dogs Canis familiaris and domestic cats Felis catus. This is the first record of C. ferox in the Mariarano forest area. We discuss the significance of this
finding, as well as a potential extirpation of E. major in the Matsedroy forest patch.

A CDV epidemic in Serengeti

Roelke-Parker, M. E., Munson, L., Packer, C., Kock, R., Cleaveland, S., Carpenter, M., ... & Mwamengele, G. L. (1996). A canine distemper virus epidemic in Serengeti lions (Panthera leo). Nature, 379(6564), 441-445.

CANINE distemper virus (CDV) is thought to have caused several fatal epidemics in canids within the Serengeti–Mara ecosystem of East Africa, affecting silver-backed jackals (Canis mesomelas) and bat-eared foxes (Otocyon megalotis) in 1978 (ref. 1), and African wild dogs (Lycaon pictus) in 1991 (refs 2, 3). The large, closely monitored Serengeti lion population4,5 was not affected in these epidemics. However, an epidemic caused by a morbillivirus closely related to CDV emerged abruptly in the lion population of the Serengeti National Park, Tanzania, in early 1994, resulting in fatal neurological disease characterized by grand mal seizures and myoclonus; the lions that died had encephalitis and pneumonia. Here we report the identification of CDV from these lions, and the close phylogenetic relationship between CDV isolates from lions and domestic dogs. By August 1994, 85% of the Serengeti lion population had anti-CDV antibodies, and the epidemic spread north to lions in the Maasai Mara National reserve, Kenya, and uncounted hyaenas, bat-eared foxes, and leopards were also affected.

Disease and endangered species

Thorne, E., & Williams, E. S. (1988). Disease and endangered species: the black‐footed ferret as a recent example. Conservation Biology, 2(1), 66-74.

Diseases may play major roles in the conservation of endangered species. Although the threat of disease received extensive consideration and influenced research and management activities governing the endangered black-footed ferret (Mustela nigripes) in Wyoming, a canine distemper epizootic in 1985 severely affected a captive breeding program and led to extirpation of the species from the wild. This recent example of the catastrophic effect of epizootic disease in an endangered species is described in an historical context. In addition, examples are given of disease further endangering other rare species, including Mauritius pink pigeon, Père David's deer, cranes, maned wolves, native Hawaiian birak, cheetahs, and others.

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Las enfermedades pueden jugar un papel importante en la conservación de especies en peligro de extinción. Aunque la amenaza de enfermedad recibió gran consideratión e influyó en la investigación y las actividades de manejo del hurón de patas-negras (Mustela nigripes), especie en peligro de extinción en Wyoming en 1985 el moquillo canino epizoótico impactó severamente un programa de crianza en cautiverio y condujo a la extinción de esta especie en su ambiente silvestre. Este reciente ejemplo del efecto catastrófico de una enfermedad epizoótica sobre una especie en peligro de extinción es descrito en un contexto histórico. Además, se dan ejemplos de enfermedades que amenazan aun más a otras especies raras, incluyendo la paloma rosada de Mauricio, el ciervo de David, el lobo de crin, el guepardo, diversas grullas, varias aves de las islas de Hawaii, entre otros.

Exposure of wild carnivores to Leptospira

Jorge, R. S. P., Ferreira, F., Ferreira Neto, J. S., Vasconcellos, S. D. A., Lima, E. D. S., Morais, Z. M. D., & Souza, G. O. D. (2011). Exposure of free-ranging wild carnivores, horses and domestic dogs to Leptospira spp in the northern Pantanal, Brazil. Memórias do Instituto Oswaldo Cruz, 106(4), 441-444.

Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collected. Serum samples were tested for the presence of Leptospira antibodies using the microscopic agglutination test. Thirty-two wild carnivores (42.7%) were considered positive with titres > 100, and 18 domestic dogs (17.5%) and 20 horses (74.1%) were also found to be positive. Our study showed that horses, dogs and several species of free-ranging wild carnivores have been exposed to Leptospira spp in the Pantanal, suggesting that the peculiar characteristics of this biome, such as high temperatures and an extended period of flooding, may favour bacterial persistence and transmission. In this region, wild carnivores and horses seem to be important hosts for the epidemiology of Leptospira species.

Evidence for domestic dogs as a source of canine distemper virus infection for Serengeti wildlife

Cleaveland, S., Appel, M. G. J., Chalmers, W. S. K., Chillingworth, C., Kaare, M., & Dye, C. (2000). Serological and demographic evidence for domestic dogs as a source of canine distemper virus infection for Serengeti wildlife. Veterinary microbiology, 72(3), 217-227.

Following an epidemic of canine distemper virus (CDV) in Serengeti lions in 1994, the role of domestic dogs in the epidemiology of the disease was investigated by serological and demographic analyses. From 1992 to 1994, data were collected from two domestic dog populations bordering the Serengeti National Park. Several lines of evidence indicated that patterns of CDV infection differed significantly between higher-density dog populations of Serengeti District to the west of the park and lower-density populations of Ngorongoro District to the south-east: (a) CDV age-seroprevalence patterns differed significantly between years in Ngorongoro District populations but not in Serengeti District populations; (b) CDV seropositive pups (<12 months of age) were detected in Ngorongoro District only in 1994, whereas a proportion of pups in Serengeti District were seropositive in each year of the study; (c) in Ngorongoro District, the proportion of deaths attributed to disease was significantly higher in 1994 than in 1993, whereas in Serengeti District, there was no significant difference in disease-related mortality between years; (d) in Ngorongoro District, significantly more CDV seronegative dogs than seropositive dogs died in 1994, whereas there was no difference in survival of CDV seropositives and seronegatives between years in Serengeti District. We concluded that, between 1992 and 1994, CDV persisted in higher-density dog populations of Serengeti District, but occurred only sporadically in lower-density Ngorongoro District populations. Data from Ngorongoro District are consistent with exposure of dogs to CDV in 1991 and 1994, but not in 1992 and 1993. These findings suggest that higher-density domestic dog populations to the west of the Serengeti National Park were a more likely source of CDV infection for wildlife during 1994 than lower-density pastoralist dogs to the south and east of the park.

Canine distemper in endangered Ethiopian wolves

Gordon, C. H., Banyard, A. C., Hussein, A., Laurenson, M. K., Malcolm, J. R., Marino, J., ... & Sillero-Zubiri, C. (2015). Canine distemper in endangered Ethiopian wolves. Emerging infectious diseases, 21(5), 824.

The Ethiopian wolf (Canis simensis) is the world’s rarest canid; ≈500 wolves remain. The largest population is found within the Bale Mountains National Park (BMNP) in southeastern Ethiopia, where conservation efforts have demonstrated the negative effect of rabies virus on wolf populations. We describe previously unreported infections with canine distemper virus (CDV) among these wolves during 2005–2006 and 2010. Death rates ranged from 43% to 68% in affected subpopulations and were higher for subadult than adult wolves (83%–87% vs. 34%–39%). The 2010 CDV outbreak started 20 months after a rabies outbreak, before the population had fully recovered, and led to the eradication of several focal packs in BMNP’s Web Valley. The combined effect of rabies and CDV increases the chance of pack extinction, exacerbating the typically slow recovery of wolf populations, and represents a key extinction threat to populations of this highly endangered carnivore.

Adult and subadult Ethiopian wolf population in Sanetti Plateau, Ethiopia, 2002–2013. Dots indicate wolf population estimates at different time points; arrows indicate canine distemper virus outbreaks in this study.

Density of adult and subadult Ethiopian wolf population in Web Valley, Ethiopia, 2002–2013. Dots indicate wolf population estimates at different time points; arrows indicate known rabies epizootics and canine distemper virus outbreaks in this study. Of 7 wolf packs in Web Valley, 4 went extinct after the 2010 canine distemper virus outbreak; in 2011, two new packs formed in the area.

Feral dog impact on a urban fragment of Atlantic forest in Brazil

Galetti, M. & I. Sazima. 2006 . Impacto de cães ferais em um fragmento urbano de Floresta Atlântica no sudeste do Brasil.  Natureza & Conservação 4 (1): 58-63

Os cães ferais domésticos são um dos principais predadores da vida selvagem nativa em áreas
protegidas em todo o mundo. Entretanto, o número de presas caçadas por cães ferais não é registrado
de maneira precisa. Foram encontradas, em um fragmento urbano de 250 hectares de Floresta
Atlântica na Região Sudeste do Brasil, 46 carcaças de no mínimo 12 espécies de vertebrados, caçadas
pelos cães ao longo de 44 meses. Os cães ferais não demonstraram qualquer seleção aparente em
relação às diferentes espécies de presa, matando desde veados a pequenos sapos. Os mamíferos
foram a presa mais freqüentemente encontrada (75%). Nossos dados indicam que os cães ferais têm
um grande impacto sobre a vida selvagem da Floresta Atlântica, especialmente em áreas onde os
animais silvestres precisam mover-se entre os fragmentos florestais. Os programas de erradicação,
embora controversos, são a única maneira de reduzir a predação da vida selvagem por cães ferais.

Feral dogs are one of the main predators of native wildlife inside protected areas all around the world. Nevertheless, the number of preys hunted by feral dogs has not been precisely recorded. In a 250 hectares Atlantic forest fragment in Southeast Brazil, 46 carcasses have been found from at least 12 vertebrate species, hunted by feral dogs along 44 months. Feral dogs didn't have any apparent selection related to their different preys, killing from deer to small toads. Mammals were the most frequently found preys (75%). Our data show that feral dogs have a great impact on wildlife in the Atlantic forest, especially in areas where wild animals have to move between forest fragments. Eradication programs, even if controversial, are the only way to reduce predation of wildlife by feral dogs.

Toxoplasmosis in sea lions in NZ

Michael, S. A., Howe, L., Chilvers, B. L., Morel, P. C. H., & Roe, W. D. (2016). Seroprevalence of Toxoplasma gondii in mainland and sub-Antarctic New Zealand sea lion (Phocarctos hookeri) populations. New Zealand Veterinary Journal, (just-accepted), 1-14.

AIMS: To investigate the seroprevalence to Toxoplasma gondii in New Zealand sea lions (Phocarctos hookeri), as a potential contributor to reproductive failure.
METHODS: Archived sera were sourced from New Zealand sea lions from two recolonising mainland populations in the Otago Peninsula (n=15) and Stewart Island (n=12), as well as a declining population at Enderby Island (n=28) in the New Zealand sub-Antarctic. Sera were tested for antibodies to T. gondii using a commercially available ELISA (with samples considered positive if the sample to positive ratio was >30%), and latex agglutination test (LAT; with titres ≥1:32 considered positive). Western blot analysis was used to validate the results of a subset of 14 samples.
RESULTS: Five samples from sea lions in mainland locations were confirmed positive for antibodies to T. gondii. Two adult females exhibited high LAT antibody titres (min 1:2048, max 1:4096) on both occasions when sampled 1 and 2 years apart, respectively. No animals from Enderby Island were seropositive.
CONCLUSIONS: Toxoplasma gondii infection is unlikely to be a major contributor to poor reproductive success in New Zealand sea lions. However, continued surveillance is pertinent to assess subclinical and clinical impacts of the parasite on these threatened populations. The commercial tests evaluated here, with further species-specific threshold refinement could provide a fast, inexpensive and reliable indicator of T. gondii exposure in New Zealand sea lions.

Toxoplasmosis may lead to road kills of Persian leopards

Namroodi, S., Gholami, A., & Shariat-Bahadori, E. (2016). Toxoplasmosis may lead to road kills of Persian leopards (Panthera pardus saxicolor) in Golestan national park, Iran. Journal of Wildlife Diseases.

Three Persian leopards (Panthera pardus saxicolor) that died from car accidents in Golestan National Park, Iran, were examined for Toxoplasma gondii and rabies virus infection. Acute T. gondii infection was diagnosed in two Persian leopards but no rabies virus was detected. Acute toxoplasmosis may be one of the factors leading to Persian leopard road kills.