First reported case of Trichomonas gallinae infection in red-breasted toucan (Ramphastos dicolorus).

This study reports the infection and diagnosis of the protozoan morphologic complex Trichomonas gallinae in a baby red-breasted toucan (Ramphastos dicolorus). Nodular lesions on the soft palate and edema in the oral cavity were observed macroscopically. Microscopically, a granuloma with multiple layers of necrosis interspersed with inflammatory polymorphonuclear infiltrates was observed. Parasitism was confirmed by parasitological diagnosis, isolation of the flagellates in culture medium, and Polymerase Chain Reaction (PCR) using 5.8S ribosomal RNA (rRNA). Flanking internal transcribed spacer (ITS) gene regions were amplified by polymerase chain reaction, and the sequences were analyzed phylogenetically using MEGA 11 software. Phylogenetic analysis based on ITS1/5.8S rRNA/ITS2 sequences demonstrated high nucleotide identity with two Trichomonas sequences available in GenBank, which were more closely related to T. vaginalis (99%) than to T. gallinae (98%). In addition to being potential transmitters of this protozoan, rigorous monitoring of infectious and parasitic diseases in wild bird populations is essential for their preservation. The forms of transmission of Trichomonas sp. favor the occurrence of the disease in many non-Columbiformes species, which is essential for the monitoring of this disease in wild birds.

Activity of cumin essential oil to control fascioliasis: Efficacy and changes in the tegument of Fasciola hepatica.

Fasciola hepatica, the liver trematode, infects ruminants and causes economic loss. Because parasites are developing resistance to commercial drugs, the negative effects of parasitism are increasing. In this study, we aimed to evaluate the efficacy of cumin (Cuminum cyminum) essential oil against F. hepatica eggs and adults. The eggs were incubated with eight concentrations of the essential oil (0.031125-4.15 mg/mL), and viable eggs were counted after 14 days and classified as embryonated or non-embryonated. Adult flukes were incubated in Roswell Park Memorial Institute medium to ensure their viability and then incubated in essential oil. They were observed for 24 h after treatment. The adults were assessed with the two lowest effective oil concentrations used in the ovicidal test. Three controls were used for both tests: nitroxynil, a negative control, and Tween®80. After incubation in oil, the adult specimens were processed for histological analysis and stained with hematoxylin-eosin. In addition, the oil was tested for cytotoxicity using Madin-Darby bovine kidney cells to assess any possible effect on them. The oil was effective in ovicidal and adulticidal inhibition of the trematode, with statistically significant results. All concentrations assessed in the ovicidal test were 100% effective. The adult test was effective within 15 h and inactivated all the specimens at the highest concentration evaluated (0.06225 mg/mL). Histological analysis showed that cumin essential oil resulted in marked areas of vacuolization. The spines showed no structural changes but were surrounded by microvesicles. These findings indicated that cumin oil could be a potential compound in the control of fasciolosis.

Adulticidal Activity of Melaleuca alternifolia (Myrtales: Myrtaceae) Essential Oil With High 1,8-Cineole Content Against Stable Flies (Diptera: Muscidae).

The stable fly, Stomoxys calcitrans (Linnaeus 1758), is a hematophagous fly responsible for causing loss of performance in horses, causing losses in cattle productivity, and impacting the animals' health through the spread of pathogenic microorganisms. The objective of this work was to investigate the insecticidal activity of essential oil obtained from Melaleuca alternifolia (Cheel), presenting high 1,8-cineole content, against S. calcitrans adults. Insecticidal activity was determined using surface application methods and exposure to oil impregnated paper. It was observed that treatments at 25 and 50 µg/cm2 (P < 0.05) present fumigant activity through exposure to the impregnated paper, and in the first 15 min of exposure, the mortality rates obtained for these treatments were, respectively (96.6 ± 3.3% and 100%), equivalent to the positive control. Using the superficial application method, the only treatment concentration presenting adulticidal action was 5% (w/v) (P < 0.05). Respective toxicities LC50 (%, w/v) and LC80 for the impregnated paper method were 1.06 ± 0.02 and 1.47 ± 0.17; for the superficial application method, they were 3.82 ± 0.65 and 5.53 ± 0.74. As demonstrated, M. alternifolia essential oil presents adulticidal potential against S. calcitrans.