A molecular survey was conducted for several hemoparasites of domestic dogs and three species of wild carnivores from two sites in Zambia. Three Babesia spp. were detected including Babesia felis and Babesia leo in lions (Panthera leo) and a Babesia sp. (similar to Babesia lengau) in spotted hyenas (Crocuta crocuta) and a single lion. All wild dogs (Lycaon pictus) and domestic dogs were negative for Babesia . High prevalences for Hepatozoon were noted in all three wild carnivores (38-61 %) and in domestic dogs (13 %). Significantly higher prevalences were noted in hyenas and wild dogs compared with domestic dogs and lions. All carnivores were PCR negative for Ehrlichia canis , Ehrlichia ewingii, and Bartonella spp. Overall, high prevalences and diversity of Babesia and Hepatozoon were noted in wild carnivores from Zambia. This study is the first molecular characterization of Babesia from any hyena species and is the first report of a Babesia sp. closely related to B. lengau, a parasite previously only reported from cheetahs (Acinonyx jubatus ), in lions and hyenas. Although usually benign in wild carnivores, these hemoparasites can be pathogenic under certain circumstances. Importantly, data on vectors for these parasites are lacking, so studies are needed to identify vectors as well as determine transmission routes, infection dynamics, and host specificity of these hemoparasites in wildlife in Africa and also the risk of transmission between domestic animals and wildlife.
Keywords:Aerial broadcast Brodifacoum rodenticide Invasive rodent eradication Toxicant residue Trophic level bioaccumulation Tropical island forest a b s t r a c tThe use of rodenticides to control or eradicate invasive rats (Rattus spp.) for conservation purposes has rapidly grown in the past decades, especially on islands. The non-target consequences and the fate of toxicant residue from such rodent eradication operations have not been well explored. In a cooperative effort, we monitored the application of a rodenticide, 'Brodifacoum 25W: Conservation', during an attempt to eradicate Rattus rattus from Palmyra Atoll. In 2011, Brodifacoum 25W: Conservation was aerially broadcasted twice over the entire atoll (2.5 km 2 ) at rates of 80 kg/ha and 75 kg/ha and a supplemental hand broadcast application (71.6 kg/ha) occurred three weeks after the second aerial application over a 10 ha area. We documented brodifacoum residues in soil, water, and biota, and documented mortality of non-target organisms. Some bait (14-19% of the target application rate) entered the marine environment to distances 7 m from the shore. After the application commenced, carcasses of 84 animals representing 15 species of birds, fish, reptiles and invertebrates were collected opportunistically as potential non-target mortalities. In addition, fish, reptiles, and invertebrates were systematically collected for residue analysis. Brodifacoum residues were detected in most (84.3%) of the animal samples analyzed. Although detection of residues in samples was anticipated, the extent and concentrations in many parts of the food web were greater than expected. Risk assessments should carefully consider application rates and entire food webs prior to operations using rodenticides.Published by Elsevier Ltd.
Disease transmission within and among wild and domestic carnivores can have significant impacts on populations, particularly for threatened and endangered species. We used serology to evaluate potential exposure to rabies virus, canine distemper virus (CDV), and canine parvovirus (CPV) for populations of African lions (Panthera leo), African wild dogs (Lycaon pictus), and spotted hyenas (Crocuta crocuta) in Zambia's South Luangwa National Park (SLNP) and Liuwa Plain National Park (LPNP) as well as community lands bordering these areas. In addition, domestic dogs in the study region were evaluated for exposure to CDV and rabies. We provide the first comprehensive disease exposure data for these species in these ecosystems. Twenty-one lions, 20 hyenas, 13 wild dogs, and 38 domestic dogs were sampled across both regions from 2009 to 2011. Laboratory results show 10.5% of domestic dogs, 5.0% of hyenas, and 7.7% of wild dogs sampled were positive for CDV exposure. All lions were negative. Exposure to CPV was 10.0% and 4.8% for hyenas and lions, respectively. All wild dogs were negative, and domestic dogs were not tested due to insufficient serum samples. All species sampled were negative for rabies virus neutralizing antibodies except lions. Forty percent of lions tested positive for rabies virus neutralizing antibodies. Because these lions appeared clinically healthy, this finding is consistent with seroconversion following exposure to rabies antigen. To our knowledge, this finding represents the first ever documentation of rabies virus neutralizing antibodies consistent with rabies exposure that did not lead to clinical disease in free-ranging African lions from this region. With ever-increasing human pressure on these ecosystems, understanding disease transmission dynamics is essential for proper management and conservation of these carnivore species.
The small Indian mongoose (Herpestes auropunctatus) is an invasive species and rabies reservoir in Puerto Rico. In the continental United States, terrestrial wildlife rabies is primarily managed by the National Rabies Management Program (NRMP) of the United States Department of Agriculture through oral rabies vaccination (ORV); the distribution of the vaccine baits is influenced by the population density of the target species. The NRMP uses a density index for estimating raccoon (Procyon lotor) population density to guide bait distribution. In Puerto Rico, a wildlife rabies vaccination program does not exist and vaccination of domestic animals is limited and not compulsory. To acquire information on density and other population dynamics, we compared a mongoose density index (MDI) adapted from the NRMP raccoon density index (RDI) to 3 other methods (2 types of capture-mark-recapture [CAPTURE and MARK] and spatially explicit capture-recapture [SECR]) for estimating density that incorporate modeling procedures on detection probabilities, and examined the spatial distribution of mongooses within our study plots. We used the RDI trapping protocol modified for mongooses to livetrap mongooses in El Yunque National Forest (El Yunque) and Cabo Rojo National Wildlife Refuge (Cabo Rojo) in fall of 2011 and spring of 2012 resulting in 4 trapping sessions. The MDI estimates were consistently less than those from other methods for estimating mongoose densities. The MDI detected a greater mongoose density during the wet season (0.55 mongooses/ha) than the dry season (0.34 mongooses/ha) at Cabo Rojo, consistent with all 3 other density estimation methods. Overall, the correlation coefficient between MDI and the other calculation methods was !0.68. When we examined known locations of mongooses and travel distances, we detected more mongooses in a smaller area within the study plot at Cabo Rojo than at El Yunque. The MDI provided information on the spatial distribution of mongooses, which will be needed to implement an ORV program to target mongooses in Puerto Rico. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
The small Indian mongoose (Herpestes auropunctatus) was introduced to several Caribbean Islands to control rat (Rattus spp.) damage to sugarcane plantations. Mongooses failed at suppressing rat populations and are now considered pests throughout most of their introduced range. Importantly, mongooses are rabies reservoirs on several Caribbean Islands. In Puerto Rico, mongooses have been implicated in up to 70% of reported animal rabies cases. There is no rabies vaccination program for wildlife in Puerto Rico, and data on rabies in mongooses are limited. We conducted a serosurvey of mongooses in two different ecologic environments in Puerto Rico: El Yunque National Forest and Cabo Rojo National Wildlife Refuge. We collected 119 serum samples from 112 mongooses, 44 (39.3%) of which were positive for rabies virus-neutralizing antibodies. We also collected oral swabs from 147 mongooses, including 88 from which we also collected serum. No oral swabs were positive for rabies virus RNA. Our data support previous research suggesting rabies virus is circulating within the mongoose population on Puerto Rico.
Bovine tuberculosis (bTB) is endemic in freeranging white-tailed deer (Odocoileus virginianus) in MI, USA. Currently, the rates of farm visitation by deer and couse of forage resources by cattle and deer are poorly understood. To evaluate the extent deer and livestock may share forage resources, we investigated farm, yard, and cattle-use area visitation by white-tailed deer and compared visitation with common livestock management practices. We fitted 25 female white-tailed deer near the bTB-infected zone in Michigan's Lower Peninsula with global positioning system collars. Livestock management practices associated with farm visitation included presence of confined feeding pastures, number of cattle water sources, and the number of cattle pastures. Fewer farm visits occurred at night than during the day. A higher proportion of nighttime visits occurred between midnight and sunrise. Visitation to yards and cattle-use areas were similar: a higher proportion of visits occurred at night, and a higher proportion of nighttime visits occurred between midnight and sunrise. Multiple visits during the same day were common. Visitation increased through spring and peaked during the fawning season. Results suggest that mitigation and control efforts to guard against potential transmission of bTB should include the season and time of day during which deer visitation occurs. Furthermore, specific livestock management practices may contribute to farm visitation by deer. Deer visiting multiple farms may contribute to local area spread of bTB.Focusing risk mitigation efforts on individual deer that are most likely to visit farms may reduce potential bTB transmission.
Diphacinone and chlorophacinone, first-generation anticoagulant rodenticides, are frequently used for control of California ground squirrels (Spermophilus beecheyi) in agricultural and rangeland areas in California, USA. Owing to growing concerns over the risks to non-target species associated with the use of these rodenticides, the USA Environmental Protection Agency (EPA) proposed that the concentration of baits for above-ground use should be reduced from 0.01% to 0.005% active ingredient. We conducted field trials to compare the efficacy of 0.005% and 0.01% chlorophacinone and diphacinone baits in broadcast and spot applications for control of California ground squirrels on rangeland. We found no significant difference in efficacy owing to bait type, concentration or application method. Repeat testing is needed in other habitat types (e.g. crop areas) where alternative foods might reduce the effectiveness of a 0.005% bait application.
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