In vitro evaluation of the activity of Cinnamaldehyde as an inhibitor of the biological cycle of Ctenocephalides felis felis

The objective of this work was to evaluate the in vitro activity of cinnamaldehyde as an inhibitor of the biological cycle of Ctenocephalides felis felis. Tests were carried out with six repetitions containing 10 eggs of C. felis felis together with 0.5g of diet and filter paper discs with area of 23.76 cm2 impregnated with different concentrations of cinnamaldehyde (6; 8; 10; 12; 14; 16; 18; 20; 24 and 28 µg.cm-2) in Petri dishes and incubated in a climate-controlled chamber at 27 ± 1 °C and RH 75 ± 10%, for 30 days. The tests included a placebo group containing the diluent (acetone) and a negative control group, without treatment. At the end of 30 days, the percentage of inhibition of adult emergence/mortality was calculated, as well as the LC50 and LC90. Inhibition of adult emergence greater than 50% was observed from a concentration of 10 µg.cm-2 and 100% inhibition from a concentration of 14 µg.cm-2, obtaining LC50 and LC90 results of 8.75 and 13.57 µg.cm-2, respectively. We concluded that the volatile compound cinnamaldehyde is effective in vitro as an inhibitor of the biological cycle of C. felis felis.

Prevalence of gastrointestinal parasites in domestic cats (Felis catus) diagnosed by different coproparasitological techniques in the municipality of Seropédica, Rio de Janeiro

The objectives of this work were to investigate the occurrence of parasites in feces of cats, compare different coproparasitological techniques for their diagnosis and determine associations with parasitism. The samples were processed using three different coproparasitological techniques: centrifugal flotation in sucrose, centrifugal flotation in ZnSO4 and simple sedimentation. The parasitic association between parasitism and variables such as age, sex and fecal consistency was performed using the chi-square test or the G test with a significance level of 5%. A total of 237 samples were analyzed, of which 93 (39.2%) were positive, being Ancylostoma spp. (17.3%), Giardia intestinalis (12.2%), Platynosomum illiciens (8.0%), Cystoisospora spp. (6.3%), Toxoplasma gondii/ Hammondia hammondi (3.4%), Diphyllobothriidae (2.1%), Toxocara spp. (1.7%), Dipylidium caninum (1.3%) and Mesocestoides spp. (0.8%). In the parasitism association analysis, it was possible to verify a statistical difference in the age category for Cystoisospora spp. (p=0.001) observing a strong relationship between parasitism and young animals, the association with sex proved to be important for P. illiciens (p<0.001) with a higher frequency of parasitized females and fecal consistency revealed to be related to the parasites G. intestinalis (p=0.007) and P. illiciens (p=0.033) showing a higher number of positive animals for these parasites with normal fecal consistency. In conclusion, we observed a higher occurrence of Ancylostoma spp. and G. intestinalis in fecal samples from domestic cats received in routine diagnoses and the presence of other parasites with zoonotic potential, as well as the relationship of these diagnosed parasites with the categories sex, age and fecal consistency.

Parasitism by Amblyomma rotundatum Koch, 1844 (Acari: Ixodidae) associated with blefaritis on a red-footed tortoise (Chelonoidis carbonarius) in Rio de Janeiro state - case report

Amblyomma rotundatum is a tick species commonly found on reptiles and amphibians. In Brazil, investigations of this ectoparasite have indicated its distribution across all Brazilian biomes, although it is concentrated in certain locations. In this context, the objective of the present study was to describe a case of parasitism by A. rotundatum in a red-footed tortoise (Chelonoidis carbonarius) in the state of Rio de Janeiro. A female red-footed tortoise (C. carbonarius), seized by the environmental police, was parasitized by a tick in the left periocular region. The tick was manually removed, preserved in 70º GL ethanol, and sent for identification at the Federal Rural University of Rio de Janeiro (UFRRJ). Based on the morphological evaluation Dantas-Torres et al. (2019), Barros-Battesti et al. (2006) and Lampo et al. (1997), a diagnosis of a female specimen of A. rotundatum was made. In conclusion, this study reports the first case of A. rotundatum parasitizing C. carbonarius in the state of Rio de Janeiro, highlighting the presence of periocular blepharitis associated with this parasitism.

Resistance of Haemonchus contortus to monepantel in sheep: first report in Espírito Santo, Brazil

The objective of this study was to provide the first report of resistance of Haemonchus contortus to monepantel in sheep in Espírito Santo. The study was conducted in a property with history of monepantel use since 2014 and register of low efficacy in studies conducted over the past few years with fecal egg count reduction test. Lambs born on the property (males and females aged approximately 100 days) were selected and after eggs per gram of feces (EPG) analysis on fecal samples, these were divided into two groups: a group treated with monepantel (2.5 mg / Kg) and a control group without anthelmintic treatment. Seven days later, the animals were euthanized to recover parasites from the gastrointestinal tract. The efficacy of the treatment was 61.35% against H. contortus, thus proving that anthelmintic resistance to monepantel was present.

Physiological alterations in Pseudosuccinea columella (Mollusca: Gastropoda) after infection by Heterorhabditis baujardi LPP7 (Rhabditida: Heterorhabditidae)

The snail Pseudosuccinea columella participates in the distribution of Fasciola hepatica in the environment by acting as its intermediate host. Therefore, the control of this lymnaeid is one of the ways to prevent hepatic fascioliasis. The objective of this study was to evaluate the susceptibility of P. columella to infective juveniles (IJs) of the entomopathogenic nematode (EPN) Heterorhabditis baujardi in laboratory conditions, as well as to investigate aspects related to the biochemistry and histopathology of snails exposed or not to the EPNs during three weeks. The EPN exposure induced significant reductions in the concentrations of glucose, total proteins and glycogen (gonad-digestive gland complex) in the snails during the onset of the infection, with the levels being restored as the infection progresses. These alterations were accompanied by increased hemolymph activities of aminotransferases and lactate dehydrogenase, as well as the concentrations of uric acid after the first and second weeks of the experiment. The histopathological analyses of the exposed snails revealed cell necrosis at the end of the first week, tissue inflammatory reactions one and two weeks after exposure, and degeneration three weeks afterward in comparison with the unexposed snails. Finally, scanning electronic microscopy revealed proliferation of fibrous connective tissue three weeks after exposure. The results indicate that P. columella is susceptible to H. baujardi. The exposure favored the establishment of a negative energy balance, increased the activity of enzymes related to tissue damages and promoted accumulation of nitrogen compounds in the host snails. Additionally, was observed in P. columella exposed to the EPNs, significant tissue lesions, and demonstrated the strong pathogenic potential of H. baujardi, indicating its possible application for biological control of this snail.

Association of radioactivity of the monazite sands of the beaches of the Guarapari city with the presence of parasites of zoonotic potential

The city of Guarapari, known as "Healthy City", has as its main tourist attraction radioactive sands known as monazite sands. There are many studies aimed at quantifying radiation, but little is known about an influence of radiation levels on the life cycle of parasites with zoonotic potential, since many owners take their animals to beaches facilitating a maintenance of their cycle. The objective of the present work was to evaluate the association of the sand radiation of the beaches of the municipality of Guarapari and the presence of eggs and larvae of zoonotic potential parasites. To determine the influence of the radiation on the parasites, sand and faeces samples were collected from the beaches of Praia do Morro, Areia Preta, Castanheiras, Setiba and Santa Mônica, and how to analyze, use the simple centrifugal-flotation technique. The beaches of the present study were classified as low, medium and high radioactivity according to the dose limits that a human being can receive. The samples of sand and faeces were grouped according to a classification of the beaches where they were collected as samples. After obtaining the result, a Chi-square statistical test was performed at a significance level of 95% to evaluate an association between radiation classes and parasite presence. In general, monazitic sands have an influence on the maintenance of the cycle of zoonotic parasites found in beach sand, their correlation being inversely proportional.

EFICÁCIA DO PRODUTO A BASE DE EPRINOMECTINA 2% CONTRA Haemonchus placei, Cooperia pectinata, Cooperia punctata, Oesophagostomum radiatum E Trichostrongylus axei EM BOVINOS ARTIFICIALMENTE INFECTADOS

Prejuízos causados por helmintoses em bovinos ocorrem por ação direta, pelos danos ao rebanho, e indireta, resultantes do custo financeiro para o controle parasitário. A prática de controle estratégico, com utilização correta de anti-helmínticos e manutenção de cargas parasitárias, podem gerar resultados satisfatórios para um rebanho quanto a aspectos de produtividade. A eprinomectina, , pertence ao grupo das lactonas macrocíclicas e possui ação endectocida. O estudo teve como objetivo avaliar a atividade anti-helmíntica da eprinomectina 2%, pela via injetável subcutânea, empregada na dose de 200mcg/Kg de peso corporal, em bovinos artificialmente infectados por nematódeos gastrintestinais. Doze bovinos mestiços foram infectados artificialmente com uma cultura mista de 150.000 L3 de uma cultura de Haemonchus placei, Cooperia pectinata, Cooperia punctata, Oesophagostomum radiatum e Trichostrongylus axei (CEUA IV/UFRRJ 9867250516). Após 42 dias os animais foram divididos em grupo controle e tratado, randomizados de acordo com as contagens médias de OPGs (ovos por gramas de fezes) realizadas nos dias -7 e -2. No dia 0 os animais tratados. Foram realizadas as contagens de OPGs dos animais nos dias +1, +3, +5, +7 +9, +11 e +13. Os animais foram eutanasiados e necropsiados nos dias +14 e +15. O número médio das contagens de OPGs e o número de helmintos presentes nos bovinos tratados foram estatisticamente menores que nos bovinos do grupo controle (p≤0,05). No grupo tratado foram encontrados por animal uma média de 355 espécimes de C. pectinata, 84,5 de T. axei, 445,67 de H. placei, 818,33 de C. punctata e 29,17 de O. radiatum. Já no grupo tratado a média de parasitos encontrados por animal foi de zero para C. pectinata e T. axei, 3,33, 20 e 1,33 para H. placei, C. punctata e O. radiatum respectivamente. Houve eficácia de 100% para C. pectinata e T. axei, 99,25% para H. placei, 97,56% C. punctata e 95,43% para O. radiatum. Como no presente estudo, testes anti-helmínticos controlados e estudos de redução de OPG realizados em outros países relatam a eficácia da eprinomectina, gerando uma nova perspectiva para o controle de helmintos gastrintestinais de bovinos, com o uso seguro de uma lactona macrociclica em vacas em lactação. Conclui-se que o produto se mostrou efetivo contra as espécies H. placei, C. pectinata e T. axei e efetivo contra C. punctata O. radiatum. em teste controlado.

Molluscicidal potential of Heterorhabditis baujardi (Rhabditida: Heterorhabditidae), strain LPP7, on Lymnaea columella (Gastropoda: Pulmonata): An alternative for biological control of fasciolosis

This study elucidated for the first time, under laboratory conditions, the susceptibility of Lymnaea columella to infective juveniles of Heterorhabditis baujardi LPP7. Exposure to the nematodes induced an average mortality rate of 66.66% in the population of L. columella, with the highest values attained from the second week after exposure onward. In addition, all the reproductive parameters analyzed (total number of eggs, number of egg masses, number of eggs laid/snail, embryo hatching rate and content of galactogen stored in the albumen gland) changed as a result of the infection. The results indicate the occurrence of the phenomenon of parasitic castration in L. columella infected by H. baujardi LPP7, probably through depletion of energy reserves such as galactogen, necessary to meet the intense metabolic demands of the nematode's larval stages. Finally, histopathological analysis demonstrated an intense process of cell disorganization, characterized by the occurrence of granulomatous inflammatory reactions in tissues of exposed snails, induced by the spoliative action of the bacteria/nematode. The results suggest the use of H. baujardi LPP7 as an alternative for biological control of the population of this intermediate host, and thus of the diseases in whose epidemiological chain it participates, especially fasciolosis, in line with the recommendations of the World Health Organization (WHO).