Platynosomum (Trematoda: Dicrocoeliidae) infection in barn owls (Tyto alba) in Northeastern Brazil.

Platynosomum spp. are parasites that inhabit the gallbladder and bile ducts of various mammals and birds worldwide. Most studies of Platynosomum spp. in birds focus on the observation and morphological characterization of the parasite through parasitological or molecular examinations, with scarce literature describing anatomopathological alterations, mainly histopathological. We report the case of a male barn owl infected with Platynosomum spp.. At necropsy, the barn owl showed dilation with parasites and fibrosis of the intrahepatic bile ducts and gallbladder. Microscopically, it was possible to identify trematodes in the bile ducts associated with a lymphoplasmacytic inflammatory infiltrate. The morphological structures of the worms were described on histopathology and direct examination. The presence of parasitism that is usually cosmopolitan in wild animals represents a risk to the biodiversity of fauna in the region, as well as a warning about the spread and maintenance of the biological cycle of the worm in humans and domestic animals.

Hepatic arteriovenous malformation in a calf.

A case of hepatic arteriovenous malformation is described in a calf that presented with a marked increase in abdominal volume and died 12 h after birth. At necropsy, the calf had marked abdominal distension and haemoperitoneum. The left hepatic lobe was reduced in size and covered by slightly whitish and intensely vascularized membranous tissue. At the edge of the left lobe there were cystic structures filled with translucent fluid. On cut surface, there were multiple cavitations well delimited by whitish walls and multiple dilated blood vessels that communicated with the cavitations. Histopathology revealed an increase in the number of vascular structures of variable calibre within loose fibrous connective tissue. The diagnosis of hepatic arteriovenous malformation was based on the lesions and confirmed by immunohistochemistry. Hepatic arteriovenous malformations are rare in all species, have not been described in cattle and should be included as a cause of mortality in neonates with post-partum haemoperitoneum.

Parasitological, serological and molecular diagnosis of Dirofilaria immitis in dogs in Northeastern Brazil.

Dirofilaria immitis is a zoonotic filarid that mainly affects the domestic dog, causing a generally fatal chronic disease, known as heart worm disease. In addition to dogs, the parasite can affect wild canids, cats, and humans. Due to its importance to One Health, detection of parasitism by D. immitis in dogs can help the adoption of control measures that aim to reduce the occurrence of parasitosis in animals and humans. The detection of D. immitis is based on the use of parasitological, serological, and molecular methods, which vary in sensitivity and specificity. Therefore, the objective was to evaluate and compare the efficiency and performance of parasitological, serological, and molecular tests in the detection of D. immitis in dogs in Northeastern Brazil. Whole blood and serum from 140 dogs from the municipality of Sousa were used, varying between males and females; aged one to 17 years; pure and mixed breeds; domiciled and stray. Three microscopic parasitological techniques (MPT) were used: capillary blood smear (CBS), peripheral (PBS) and modified Knott test (MK) associated with the morphometric diagnosis of the microfilariae. For the detection of D. immitis antigens, a rapid immunochromatographic test (RIT) (ALERE Dirofilariose AG Teste kit®, Seogu-dong, Korea) was used, and polymerase chain reaction (PCR) as a molecular method. To evaluate the tests, PCR was considered the gold standard, and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) values were calculated. To verify the agreement of the tests, the Kappa test was performed (p ≤ 0.05). From the 140 analyzed samples, 33.6% (48/140) presented microfilariae, antigen and/or parasitic DNA. 23.6% (33/140) were positive in the CBS; 25.7% (36/140) in the PBS; 29.3% (41/140) in the MK; 30% (42/140) in the RIT and 28.6% (40/140) in the PCR. All methods showed almost perfect agreement with PCR, high sensitivity (0.8-0.95), specificity (0.94-0.99), and values established with VPP (0.8571-0.9722) and VPN (0.9519-0.9797). The CBS and PBS showed less sensitivity and greater specificity. MK presented the highest sensitivity and RIT was the choice for hidden infections. Considering the occurrence of D. immitis in dogs in a non-coastal region of Northeastern Brazil, an epidemiological approach is recommended to identify risk factors for this zoonotic parasitosis.