Eduardo Luiz Trindade Moreira

Biomarcadores histológicos: toxicidade crônica pelo Roundup em piauçu (Leporinus macrocephalus)

The use of gills, liver, and kidneys as histological biomarkers was evaluated in a chronic toxicity analysis with herbicide Roundup® in piaucu (Leporinus macrocephalus). The animals were exposed to 1/10 of LC50 (1.58mg/L), during a period of 14 and 28 days. Five animals were used for treatment (days 0, 14, and 28). Hepatic hemorrhage and necrosis and renal congestion were the alterations that presented differences between exposed and non-exposed animals. Among the organs used as histological biomarkers, the liver presented the best results, followed by the kidneys.

In vivo anthelmintic activity of an aqueous extract from sisal waste (Agave sisalana Perr.) against gastrointestinal nematodes in goats.

The resistance of gastrointestinal nematodes (GINs) of small ruminants to anthelmintics has required the investigation of new alternatives. The aim of the present study was to evaluate the in vivo anthelmintic activity of an aqueous extract from sisal waste (Agave sisalana) (AESW) against GINs in goats and to observe the animals for toxic effects. Thirty animals that were naturally infected with GINs were distributed into three groups: group I, was treated with daily doses of AESW (1.7 g/kg) for eight days; Group II, the positive control, was treated with a single dose of levamisole phosphate (6.3mg/kg); and group III, the negative control, was left untreated. Faecal eggs counts (FECs), coprocultures and post-mortem worm counts were performed to assess the efficacy of the treatments. Clinical and laboratory analyses were performed to evaluate any toxic effects associated with the treatment. In the goats in groups I and II, a significant reduction (p<0.05) of the number of eggs and infective larvae (L(3)) was observed. The maximum reductions of the FECs were 50.3% and 93.6% for groups I and II, respectively, whereas the percent reductions of the total number of L(3) larvae were 80% (group I) and 85.6% (group II). There was no difference between groups I and III with respect to worm burden, and the percent reductions were 28.8% and 63.4% for Oesophagostomum columbianum and Trichostrongylus colubriformis, respectively. No reduction was detected for the Haemonchus contortus. The positive control group demonstrated a 74% reduction of the parasites that were recovered from the digestive tract. There were no changes in clinical and haematological parameters. The levels of serum urea and creatinine were higher in group I, but remained within the normal range. At necropsy, pale mucous membranes, abomasitis and enteritis were associated with parasitism. In addition, a histological analysis of the liver and kidney did not reveal any changes suggestive of toxicity. A chemical analysis of the AESW demonstrated the presence of saponins, which after acid-hydrolyses reaction, gave the sapogenins hecogenin and tigogenin. The AESW had a low efficacy for the parasitic stages and was moderately effective against eggs and free-living stages. Furthermore, the treatment was not toxic to the goats.

Atividade anti-helmíntica do extrato aquoso das folhas de Zanthoxylum rhoifolium Lam. (Rutaceae)

The study evaluated the anthelmintic activity of aqueous extract of Zanthoxylum rhoifolium leaves in two experiments. In vitro test, cultures of goat fecal samples were treated with different concentrations of extract (134.5 to 335.0 mg.mL(-1)). In vivo test was composed of 20 sheep: G1: treated with 0.63 g.kg(-1), during four days; G2: same dose, for eight days; G3: ivermectin (200 microg.kg(-1)) and G4 untreated group. In vitro results showed a reduction of Haemonchus spp, Trichostrongylus spp. and Oesophagostomum spp. larvae greater than 95% in the concentrations between 335.0 and 193.7 mg.mL(-1). Faecal egg counting reduction was 51, 56 and 90% in G1, G2 and G3, respectively, while immature stages and adults ranged from 0 to 91% in G1 and from 26 to 94% in G2. Ivermectin effectiveness was 99% for L4 and L5 of H. contortus and 100% for other nematodes species. Clinical and biochemical parameters have remained in the normality and histophatologic analyses did not show alteration suggesting absence of toxicity. Although the great effectiveness of Z. rhoifolium leaves extract in vitro test, it displayed poor efficiency in vivo regarding gastrointestinal nematodes reduction.

Parâmetros hematológicos e alterações histopatológicas em bijupirá (Rachycentron canadum Linnaeus, 1766) com amyloodiniose

O objetivo do trabalho foi descrever os parâmetros hematologicos e as alteracoes histopatologicas em bijupiras infectados por Amyloodinium ocellatum. Um grupo de 27 peixes foi anestesiado para coleta de amostras de sangue e eutanasiados para coleta de muco e fragmentos de tecido cutâneo e branquial. Foram avaliadas a prevalencia e a intensidade parasitaria da infeccao, assim como os valores de parâmetros hematologicos e alteracoes histopatologicas. A prevalencia parasitaria nas brânquias foi de 100% e no muco foi de 80,8% e as intensidades parasitarias medias foram de 683,5 nas brânquias, e 67,1 no muco cutâneo. Os valores medios dos parâmetros hematologicos foram: eritrocitos 4,3x106µL; VG 26%; VGM 64,2fL; proteina plasmatica 5,8mg/dL; trombocitos 5,2 x103/µL e leucocitos 3,6 x103/µL. Alem disso, foram verificadas hiperplasia do epitelio respiratorio acompanhada de fusao lamelar, descolamento do epitelio, dilatacao do seio venoso, formacao de aneurisma, ruptura do epitelio lamelar, hemorragia, necrose, reacao inflamatoria linfocitica. O parasito foi observado nas lamelas branquiais, o VMA variou do grau discreto ao severo e o IAH foi de 76,8. A pesquisa assume importância por se tratar dos primeiros estudos em Rachycentron canadum, um peixe que se destaca com potencial ao cultivo.

Evaluation of anthelmintic activity of liquid waste of Agave sisalana (sisal) in goats

It was evaluated the anthelmintic activity of Agave sisalana (sisal) juice against gastrointestinal nematodes and its potential toxic effects in goats. In vitro tests showed more than 95% reduction in larval counts of the genus Haemonchus spp. at concentrations between 86.5 and 146.3 mg.mL(-1). In vivo the percent reduction of larvae of the fourth (L4) and fifth (L5) stages of Haemonchus, Oesophagostomum and Trichostrongylus was less than 95% in groups GI and GII, and between 80 and 90% in group GIII. A. sisalana juice at the concentrations tested in vitro was effective against gastrointestinal nematodes in goats; however, its anthelmintic efficacy was reduced when administered to animals.

Avaliação da toxicidade oral subcrônica da bixina para ratos

A bixina em po (30% de bixina), proveniente das sementes de urucum (Bixa orellana L.), foi administrada, por gavagem, a ratos Wistar, 10 animais de cada sexo, na concentracao de 0,01±0,006% de bixina/dia, em oleo de milho, cinco dias por semana, durante 13 semanas, com o objetivo de verificar a toxicidade da substância-teste para essa especie animal. A grupos controle (10 animais por sexo), foi administrado oleo de milho, para comparacao. Durante o periodo de exposicao, foram registrados o peso absoluto corporeo, o ganho de peso, o consumo de racao e a eficiencia alimentar, bem como realizadas as avaliacoes clinica e oftalmoscopica. Antes da eutanasia, os animais foram anestesiados (eter etilico) e submetidos a exames hematologicos de rotina e bioquimicos (glicose, creatinina, colesterol total, triglicerides, asparagina transaminase e g-glutamil transaminase). Durante o exame necroscopico, figado, rins, baco, adrenais e testiculos foram excisados e pesados. O estudo histologico foi realizado em amostras de figado e rins dos animais expostos e respectivos controles. A analise estatistica dos parâmetros de peso, hematologicos e bioquimicos mostrou algumas diferencas significativas entre os grupos teste e controle, as quais nao parecem estar relacionadas a exposicao. Nao foram observadas alteracoes clinicas, comportamentais, necroscopicas e histologicas. Nas condicoes do estudo, a bixina nao produziu efeitos toxicos nos animais expostos.

Diagnóstico de alterações neurológicas compressivas da medula espinal de cães com o uso da Tomografia Computadorizada (TC) Helicoidal

Neurological disorders in dogs are common in veterinary medical practice routine, being necessary to identify the site of injury in the event of compression on structures of the central nervous system (CNS). The aim of this work was an epidemiological study of neurological changes in compressive spinal cord of pet dogs in Salvador and the metropolitan area. Discopathies, neoplasms and trauma were identified by Computed Tomography (CT). We evaluated 17 dogs of various breeds, aged between 2 and 10 years old and of both sexes, from two veterinary medical routine services and forwarded to the examination as clinically indicated. Slice images with a thickness ranging from 0.5 to 2mm were produced in rotation with the tomograph. Animals that showed disc disease (70.58%) for extradural myelopathy 6/12 (50%) were the breed Dachshund, mean age 7.33±1.97 years and for all other occurrence was timely; 23.53% of vertebral bone disease, bone tumors and fractures, and 5.89% corresponding to neoplasm marrow. There was a higher incidence of injuries segments L2-L3 (25%), followed by C4-C6 (16.67%), T12-T13 (16.67%), L7-S1 (16.67%) of cases.

Investigação do gene p53 de frangos expostos às aflatoxinas

To identify the effects of aflatoxins (AFs), Cobb lineage poultry were separated in an experimental group in which they were treated with commercial ration containing 2.8ppm of total AFs during 21 days (TG) and a control group without AFs exposure (CG). In the liver of poultries exposed to AFs, alterations were microscopically observed, which were characterized by hepatomegaly, a pale yellowish aspect with some hemorrhagic spots, and histologically a trabecullar disarranging pleomorphic hepatocytes with cariomegaly, intracytoplasmatic vacuolar degeneration, necrosis, lymphocytic infiltration and hyperplasia of biliary ducts. The PCR with GSPT53c-1 primers based on p53 candidate gen (GenBank XM_424937.2) generated a product of approximately 350 base pairs. The sequenced amplicon obtained from the DNA of treated poultry did not display any mutation or deletion, and the PCR- RFLP bands patterns were also not distinct in both experimental groups. The results indicated that transversion did not occur in the fragment amplified due to AFs exposure. As a consequence of results obtained with p53 gene (NM_205264.1) we concluded that PCR-RFLP and sequencing of PCR product are not appropriate diagnostic tools for the detection of poultry exposure to AFs, at least in the experimental conditions performed.