Larvoscopic study on Dictyocaulus sp. in the faeces of beef cattle in northeastern Brazil.

The lungworm Dictyocaulus viviparus has an important role in cattle health and productivity worldwide, since infections can lead to substantial economic losses. Despite its importance, few studies investigating the epidemiological aspects of infection by this parasite have been conducted. The aim of this study was to report the occurrence of lungworm infection in beef cattle herds reared in an area of livestock production in the northeastern region of Brazil. From September 2020 to August 2021, monthly fecal samples (n = 493) were collected from 46 beef cattle. Among all the animals assessed, lungworm larvae were detected in 8.7% (4/46). None of them presented any clinical sign suggestive of infection by lungworm parasites. Twenty larvae were retrieved, with the minimum number (n = 1) detected in October and December, and the maximum number (n = 13) in November. These presented a mean length of 363 µm (± 28.65 µm) and mean width of 19 µm (± 1.03 µm), and were morphologically similar to Dictyocaulus sp.. This study reports the occurrence of this parasite in this livestock production area. Lastly, local veterinarians need to be aware of inclusion of this parasite in the differential diagnosis of other respiratory infections in beef cattle.

Vector-borne pathogens in dogs from areas where leishmaniosis is endemic.

Many vector-borne pathogens (VBPs), including Ehrlichia canis and Dirofilaria immitis, may infect simultaneously dogs in areas where Leishmania infantum is endemic, especially in the tropics, where highly abundant arthropod vectors thrive. The aim of this study was to compare the frequency of simultaneous VBPs infection in Leishmania-positive and Leishmania-negative dogs. Animals enrolled in this study were divided in two groups (G1 and G2), G1 being comprised of L. infantum-infected dogs (n = 58) and the G2 of L. infantum-negative dogs (n = 58). Blood samples were screened using a qualitative ELISA test (SNAP® 4Dx® Plus, IDEXX Laboratory, Westbrook, Maine, USA) for detection of antibodies against Anaplasma spp., Borrelia burgdorferi sensu lato, Ehrlichia spp. and antigens of Dirofilaria immitis. Overall, 89.7% (52/58) of dogs from G1 were positive for at least one VBP, whereas 50.0% (29/58) of dogs from G2 dogs were positive as well. The highest positivity was to E. canis (67.2%; 78/116), followed by D. immitis (12.9%; 15/116), and A. platys (6.0%; 7/116). None of the animals scored positive for B. burgdorferi s.l.. There was a statistically significant difference for the simultaneous positivity to E. canis plus D. immitis between groups. Furthermore, 43.1% (25/58) of dogs from G1 were infested by ectoparasites (ticks, fleas, or both), compared to 20.6% (12/58) of dogs from G2. In conclusion, Leishmania-infected dogs were more co-infected with other VBPs than Leishmania-negative animals. Therefore, it is pivotal to increase the awareness of veterinarian and dog owners about the importance of testing Leishmania-infected dogs for other VBPs, as this may directly affect treatment decisions and management.

Larvoscopic study on Dictyocaulus sp. in the faeces of beef cattle in northeastern Brazil / Estudo larvoscópico de Dictyocaulus sp. em fezes de bovinos de corte do nordeste do Brasil

Abstract The lungworm Dictyocaulus viviparus has an important role in cattle health and productivity worldwide, since infections can lead to substantial economic losses. Despite its importance, few studies investigating the epidemiological aspects of infection by this parasite have been conducted. The aim of this study was to report the occurrence of lungworm infection in beef cattle herds reared in an area of livestock production in the northeastern region of Brazil. From September 2020 to August 2021, monthly fecal samples (n = 493) were collected from 46 beef cattle. Among all the animals assessed, lungworm larvae were detected in 8.7% (4/46). None of them presented any clinical sign suggestive of infection by lungworm parasites. Twenty larvae were retrieved, with the minimum number (n = 1) detected in October and December, and the maximum number (n = 13) in November. These presented a mean length of 363 μm (± 28.65 μm) and mean width of 19 μm (± 1.03 μm), and were morphologically similar to Dictyocaulus sp.. This study reports the occurrence of this parasite in this livestock production area. Lastly, local veterinarians need to be aware of inclusion of this parasite in the differential diagnosis of other respiratory infections in beef cattle.

Resumo O parasito pulmonar Dictyocaulus viviparus tem um papel importante na saúde e produtividade bovina em todo o mundo, uma vez que infecções podem levar a perdas econômicas. Além de sua importância, poucos estudos que investigam aspectos epidemiológicos das infecções por esse parasito têm sido realizados. Objetivou-se, nesta pesquisa, relatar a ocorrência de infecção por nematódeos pulmonares em rebanhos bovinos de corte, criados em uma importante área de produção pecuária, na região Nordeste do Brasil. De setembro de 2020 a agosto de 2021, foram coletadas, mensalmente, amostras fecais (n = 493) de 46 bovinos de corte. De todos os animais avaliados, larvas de nematódeos pulmonares foram detectadas em 8,7% (4/46). Os animais não apresentaram nenhum sinal clínico sugestivo de infecção por parasitos pulmonares. Vinte larvas foram recuperadas, com o número mínimo (n = 1) detectado em outubro e dezembro, e o número máximo (n = 13) em novembro. Apresentavam comprimento médio de 363 μm (± 28,65 μm), largura média de 19 μm (±1,03 μm) e eram morfologicamente semelhantes a Dictyocaulus sp.. Este estudo relata a ocorrência desse parasito nesta área. Logo, os veterinários locais devem estar atentos à inclusão desse parasito no diagnóstico diferencial de outras infecções respiratórias em bovinos de corte.

Occurrence and anatomical distribution of myiasis caused by Cochliomyia hominivorax (Diptera: Calliphoridae) in swine.

Cochliomyia hominivorax (Diptera: Calliphoridae) has been considered the most important cause of myiasis in animals in the South America with most cases being recorded in cattle. In Brazil, the risk of myiasis in swine population is underestimated, leading to difficulties in the implementation of preventive measures. The aim of this study was to report the occurrence of myiasis infesting a swine population over a one-year period and to evaluate the anatomical distribution of these larvae on the animal's body. From May 2019 to April 2020, a total of 2038 inspections were carried out on pigs reared in two farms located in the state of Pernambuco, Northeastern Brazil. Fly larvae retrieved were morphologically identified and the anatomical distribution of myiasis was graphically represented by a heat map indicating its frequency in swine based on the interpolation of data. Cochliomyia hominivorax larvae (n = 78) of second (n = 29) and third (n = 49) developmental stages were recovered in 13 animals (0.64%) out of 2038 inspections performed. The occurrence of myiasis was detected in eight anatomical sites, with higher concentration on the forehead region and on ears. Data herein obtained provide valuable information on the epidemiology and biological aspects of C. hominivorax affecting pigs. In addition, it indicates that the forehead and ears are important sites of parasitism most likely due the high frequency of skin lesions in these areas.

Lutzomyia evandroi in a New Area of Occurrence of Leishmaniasis.

PURPOSE: Sand flies are vectors of medical and veterinary concern, responsible for the transmission of Leishmania parasites. These invertebrates are widely distributed throughout the world and their abundance and diversity is dependent on several biotic and physical factors. Based on the epidemiological importance of these insects, the aim of this study was to assess the sand fly fauna of a new area of occurrence of leishmaniasis. METHODS: From October 2018 to September 2019, samplings were performed using CDC light traps at six different collection points located in a high altitude area in the municipality of Garanhuns, Northeastern Brazil. Geographic coordinates were recorded using the satellite remote sensing Global Positioning System (GPS) Garmin Etrex20. The spatial distribution of sand flies was evaluated using kernel density estimation (KDE). Engorged females (n = 12) were molecularly processed to search for Leishmania DNA. RESULTS: A total of 138 sand fly specimens were collected during the study period, with 100% (138/138) identified as Lutzomyia evandroi. Climatic conditions did not influence the number of sand flies (males and females) collected monthly, but a statistically significant difference was observed between the number of specimens and different collections points. The kernel map showed a heterogeneous spatial distribution of sand flies in the municipality of Garanhuns with a hotspot in the south of the region. CONCLUSION: Data presented herein are pivotal in filling the gap on the epidemiology of leishmaniasis in this high altitude area, serving as an alert to local health authorities. It also indicated that the putative role of L. evandroi in the transmission of Leishmania parasites should be clarified.

Seroprevalence of Neospora caninum and Toxoplasma gondii in dogs from an urban area of North-eastern Brazil: a spatial approach.

INTRODUCTION: The present study aimed to assess the seroprevalence and spatial distribution of Neospora caninum and Toxoplasma gondii in dogs. METHODS: Blood samples (n = 241) were collected and analyzed for the presence of anti-N. caninum and anti-T. gondii antibodies. The spatial distribution was evaluated using kernel density estimation (KDE). RESULTS: Anti-N. caninum and anti-T. gondii antibodies were detected in 24.06% (58/241) and 9.54% (23/241) of samples, respectively. A heterogeneous spatial distribution of positive dogs was observed across the city. CONCLUSIONS: These data are pivotal for better understanding the dynamics of infection caused by these protozoa in the canine population.

Seroprevalence of neospora caninum and toxoplasma gondii in dogs from an urban area of North-eastern Brazil: a spatial approach

Abstract INTRODUCTION: The present study aimed to assess the seroprevalence and spatial distribution of Neospora caninum and Toxoplasma gondii in dogs. METHODS: Blood samples (n = 241) were collected and analyzed for the presence of anti-N. caninum and anti-T. gondii antibodies. The spatial distribution was evaluated using kernel density estimation (KDE). RESULTS Anti-N. caninum and anti-T. gondii antibodies were detected in 24.06% (58/241) and 9.54% (23/241) of samples, respectively. A heterogeneous spatial distribution of positive dogs was observed across the city. CONCLUSIONS These data are pivotal for better understanding the dynamics of infection caused by these protozoa in the canine population.