Ticks consume resources from their hosts shaping their life-history traits and are vectors of many zoonotic pathogens. Several studies have focused on the health effects of blood-sucking ectoparasites on avian hosts, but there is limited information on the effects of ticks on adult and sub-adult birds, which may actively avoid ticks and are likely to present low infestation intensities. We evaluated the effects of the presence of feeding ticks and intensity of infestation on health variables of avian hosts. We also evaluated whether these variables were affected by tick infection by Borrelia burgdorferi sensu lato (s.l.) and by the presence of Borrelia infection on the birds' skin. Presence of parasite association among ticks, haemosporidea and Borrelia within the bird-host was also tested. We found that infestation by ticks significantly increased heterophyl/lymphocyte ratio in Turdus merula suggesting increased stress. This was especially evident at high infestation intensities when a significant decrease in body mass and body condition (body mass corrected for size) was also observed. Erithacus rubecula infested with more than 10 larvae tended to have lower haematocrit and blood haemoglobin. Plasma globulin concentration in T. merula tended to be affected by the presence of attached ticks and their infection with Borrelia, but this depended on the age of the bird. No association was detected among ticks, haemosporidea and Borrelia infection. We showed that ticks have detrimental effects on their avian hosts even under natural infestation conditions and that confirmed Borrelia reservoir hosts may also present symptoms of infection, though these may be subtle.

The association of chewing lice and feather mites with wild birds of riparian forest was investigated in the Cerrado biome, Tocantins State, Brazil. The birds were captured with mist nets between July 2008 and March 2009. Ectoparasites were collected by the dust-ruffling technique. Infestation rates were determined by the sampling prevalence, abundance, and mean intensity of ectoparasites. A total of 1,479 chewing lice were collected that were distributed in 3 families and 18 genera, of which 15 taxa were identified to the species level. Sixteen genera of feather mites were found, and 10 species were identified. A high prevalence rate of chewing lice and feather mites was found in non-Passeriformes (66.7 and 50.0%) and Passeriformes (57.8 and 75.6%) birds. New host-parasite associations were registered for two species of chewing lice and for four species of feather mites, thus expanding the geographical distribution in Brazil of six chewing lice species. This is the first study of the ectoparasites of wild birds to be conducted in this region of Brazil.

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From an ecological point of view, parasites are considered important selective forces that influence all aspects of a host's life. The purpose of this study was to assess the health state of Turdus leucomelas Vieillot, 1818 (Turdidae: Passeriformes) inhabiting a Brazilian Cerrado in the breeding and molting seasons through a hematological parameter analysis and an evaluation of infection by blood parasites. The birds were collected with mist-nets, ringed and blood sampled to assess hematological parameters (hematocrit, hemoglobin concentration and white blood cells) and blood parasites. We detected blood parasites through optical microscopy and subsequently used PCR (amplification of the 18sRNA gene) to verify the presence of Plasmodium spp. (avian malaria). During the breeding season, the hemoglobin level and CHGM percentage were greater. Global leukocyte count was positively related to hemoglobin level, CHGM percentage and body weight. Of the total 31 T. leucomelas individuals examined, 18 presented Plasmodium parasites (58% of prevalence). There was a significant relationship between the presence of Plasmodium spp. and decreased CHGM. These results suggest a connection between the health parameters of wild birds and the physiological stress associated with the breeding season

According to the enemy release hypothesis (ERH) the spread of invasive species will be facilitated by release from their enemies as they occupy new areas. However, the ERH has rarely been tested by comparing populations of native (non-invasive, long established) species with expanding or shifting ranges, to the same species as invasive in another area. We tested the ERH with respect to blood parasite levels (prevalence and intensity of Plasmodium spp. and Haemoproteus spp.) of (a) two closely related, widely distributed species of thrush (Turdus leucomelas and T. merula), and (b) an invasive sparrow (Passer domesticus) whose range has expanded from the Old World to the New World since the 18th century. A total of 158 birds were sampled in Portugal and 99 in Brazil. All bird species were parasitized, and 55% of the individuals collected were parasitized, and the mean intensity of infection was of 28 parasites per 10,000 erythrocytes. We assessed whether differences in levels of infection (prevalence and intensity) were due to site (tropical/New World and temperate/Old World) or host species. The ERH was supported: Passer domesticus and Turdus merula had higher levels of parasitism in the Old World than in the New World. Thus, P. domesticus seems to be benefitting from its "recent" range expansion, compared to T. leucomelas, through ecological release from its native parasites and because the parasites of the recently invaded area seem to be infesting native species instead.

Roadways and road traffic modify landscapes, posing a threat to the conservation of species in different biomes. The aim of the present study was to analyze roadkill records of wild mammals and to compare the results to findings from 37 other studies conducted in Brazil, to evaluate the richness and diversity of threatened species in different eco-regions of the country. This study was conducted between June 2007 and June 2008, along 60 km of the inter-state highway BR-364, which connects the municipalities of Ouro Preto d’Oeste and Presidente Médici in the state of Rondônia (northern Brazil). Two hundred twenty roadkills were recorded involving 13 species of mammals. Cingualata, Pilosa and Carnivora were the most represented orders. The most represented were the generalist species Dasypus novemcinctus (56.7%), Tamandua tetradactyla (10.5%), and Cerdocyon thous (8.2%), reflecting the adaptability of these species to habitat changes and presence of humans. The number of roadkilled individuals and species indicated no significant differences between the dry and rainy seasons. The findings indicate a high index of roadkills (3.38 individuals/km/year) and moderate number of run over species (0.20 species/km/year) in the region in comparison to records from other roadways in Brazil, with 46% species having an endangered status. Roadways in the eco-regions of the Cerrado (Brazilian savanna) accounted a significantly larger proportion of endangered species (mean: 52%) in comparison to the Pampa (lowlands of southern Brazil; 24%), but the differences in comparison to roadways in Amazonia (37%) and the Atlantic Forest (31%) were non-significant. The present findings underscore the need for emergency measures to minimize the impact of roadkills on mammals. Moreover, priority should be given to more impacted roadways and more threaten eco-regions.

Devido à diversidade de espécies de aves existentes nas cidades, suas funções ecossistêmicas e a necessidade de sua conservação, torna-se importante que a sociedade conheça melhor esse grupo e contribua para a sua preservação. Este trabalho constou de um relato de experiência e teve como objetivo elaborar um catálogo contendo o registro fotográfico e a identificação da avifauna do campus da Universidade do Estado de Minas Gerais (UEMG) – Unidade de Divinópolis; realizar palestras e exposições fotográficas das aves registradas na própria unidade e em escolas públicas e, ainda, oferecer minicurso sobre fotografia de aves. Os registros fotográficos possibilitaram a identificação de 90 espécies. A exposição fotográfica e palestras realizadas nas escolas possibilitaram a participação de 313 estudantes do ensino fundamental e médio. Na universidade, a palestra e a exposição fotográfica contaram com 60 e 445 participantes, respectivamente, entre discentes, docentes e funcionários. Foi também realizado o minicurso “Introdução à observação e fotografia de aves”, que contou com a presença de 17 participantes. Aliando conhecimento com uso de tecnologia, o projeto atingiu um público de diversas faixas etárias, propiciando novos conhecimentos e despertando interesse científico, especialmente no que se refere à biodiversidade da avifauna local.