The objective of this study was to evaluate the effects of protein extracts obtained from the plant Leucaena leucocephala on the nematode parasite Haemonchus contortus. The seeds, shell and cotyledon of L. leucocephala were separated and their proteins extracted using a sodium phosphate buffer, and named as TE (total seed extract), SE (shell extract) and CE (cotyledon extract). Soluble protein content, protease, protease inhibitory and chitinase activity assays were performed. Exsheathment inhibition of H. contortus larvae were performed at concentrations of 0.6 mg mL . The effective concentration for 50% hatching inhibition (EC 50 ) was estimated by probit. Different proportions of soluble proteins, protease and chitinase were found in TE and CE. Protease inhibitory activity was detected in all extracts. The EC 50 of the CE and TE extracts were 0.48 and 0.33 mg mL -1 , respectively. No ovicidal effects on H. contortus were detected in SE extracts, and none of the protein extracts demonstrated larvicidal effects on H. contortus. We therefore conclude that protein extracts of L. leucocephala had a detrimental effect on nematode eggs, which can be correlated with the high protease and chitinase activity of these extracts.Keywords: Plant proteins, protease, protease inhibitor, chitinase. ResumoO objetivo deste estudo foi avaliar a atividade anti-helmíntica de extratos proteicos de leucena (Leucaena leucocephala) sobre Haemonchus contortus. As sementes, as cascas e os cotilédones foram moídos separadamente e as proteínas extraídas com tampão fosfato de sódio e denominados: TE (extrato total), SE (extrato casca) e CE (extrato cotilédone). O teor de proteínas, atividade proteolítica, inibitória de protease e quitinolítica dos extratos foram verificados, além da ação sobre a eclosão de ovos e desembainhamento larvar de H. contortus. A concentração efetiva para inibição de 50% da eclosão dos ovos (EC 50 ) foi calculada através do probit. Foi demonstrado que TE e CE possuem, em diferentes proporções, proteínas solúveis, protease e quitinase. Atividade inibitória de protease foi encontrada em todos os extratos. A EC 50 dos extratos CE e TE foram 0,48 e 0,33 mg de proteína mL -1 , respectivamente. O extrato SE não apresentou atividade sobre a eclosão dos ovos. Os extratos proteicos não apresentaram efeito larvicida sobre H. contortus. Conclui-se que a ação de extratos proteicos de L. leucocephala afetam negativamente a eclodibilidade dos ovos, correlacionando-se com a alta atividade de protease e quitinase dos extratos testados.Palavras-chaves: Proteínas vegetais, protease, inibidor de protease, quitinase.

BackgroundTannin-rich plants have been examined as an alternative for controlling the gastrointestinal nematodes in ruminants. In vivo assays typically examine the anthelmintic activity in female fecundity and/or the adult worm burden, without considering other life-cycle stages or the impact on pasture contamination. The aim of the present study was to evaluate the anthelmintic activity of tanniniferous food from Bauhinia pulchella in goats and the potential impact on pasture contamination with the infective larval stage of gastrointestinal nematodes.FindingsSixteen cross breed Boer goats that were naturally infected with gastrointestinal nematodes were fed tanniniferous concentrate from the leaves of B. pulchella and compared to a separate paddock of control animals without condensed tannin supplementation. A range of parasite characteristics were monitored throughout the 63 days of experimentation, including faecal egg count (FEC), egg hatching and relative numbers of hatched helminth larvae on herbage. Worm free tracer animals were used to assess the infective larval stage load of the contaminated pasture. The tanniniferous food did not reduce the combined FEC values, but egg hatching was significantly affected (p < 0.05). The pasture grazed by goats fed with tanniniferous food from B. pulchella showed reduced contamination through infective larval stages. Tracer goats maintained in paddocks grazed with animals fed with tanniniferous food had lower numbers of Trichostrongylus colubriformis than did those in the control group (86 % reduction).ConclusionsCondensed tannin from B. pulchella showed anthelmintic activity, affected egg viability and reduced pasture contamination, which led to the reduced infection of the animals by T. colubriformis.

Resumo O objetivo principal deste estudo foi comparar o rendimento escolar entre alunos do 6º ano que residem nas áreas rural e urbana de uma escola pública do Piauí. Além disso, investigaram-se as causas socioeconômicas e escolares que influenciam tal rendimento, segundo os professores e os alunos. Os dados de rendimento foram obtidos mediante registros escolares, e os fatores influenciadores de rendimento foram investigados por meio de questionários e de entrevistas. Os registros escolares apontaram que os alunos que residem em área rural possuem um menor rendimento em comparação àqueles que moram na área urbana. Esta variação estaria ligada a aspectos sociais e escolares em diferentes níveis: de aluno, de turma e de escola.

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O objetivo desse artigo é discutir sobre as contribuições do estudo do meio para a formação inicial de educadores do campo para o ensino de ciências na região do semiárido piauiense no primeiro semestre de 2018. Os dados foram coletados na forma de questionários e gravações em vídeo de relatórios apresentados em seminários de 19 licenciandos de um Curso de Licenciatura em Educação do Campo. A análise dos dados mostrou que o estudo do meio se coaduna com os fundamentos da Educação do Campo. Os resultados, analisados na perspectiva crítico-social dos conteúdos, indicaram que o estudo do meio pode contribuir para o ensino contextualizado de Ciências; o fortalecimento da identidade campesina; o ensino com pesquisa; o trabalho coletivo e a reflexão crítica da realidade.

A maioria dos professores de Ciências no Brasil são graduados em Ciências Biológicas e a literatura científica nacional aponta que para estes é um desafio ensinar conteúdos de Física no Ensino Fundamental. O desafio aumenta com a prescrição pela Base Nacional Comum Curricular do conteúdo de Física distribuído ao longo de todos os anos do Ensino Fundamental. Nesse contexto, este artigo tem como objetivo apresentar e problematizar os resultados de uma investigação sobre a formação docente para o ensino de Física no Ensino Fundamental em Cursos de Licenciatura em Ciências Biológicas. Para isso, foi feito o levantamento e a análise da carga horária e do conteúdo curricular de Física, através de arquivos on-line dos cursos de Licenciatura em Ciências Biológicas de doze universidades do estado de Minas Gerais. Constatou-se que tais cursos de formação inicial apresentam uma carga horária exígua para o componente curricular de Física, o qual tem abrangência limitada dos conteúdos específicos e é desenvolvido sem vinculação com a prática de ensino para o nível fundamental.

A non-engorged adult female Amblyomma dissimile and two Amblyomma sp. larvae were found parasitizing the lizard Ameiva ameiva in the municipality of Chapadinha, State of Maranhão. This is the first record in the state of Maranhão and fills a gap in the distribution of A. dissimile in Brazil. The lizard A. ameiva represents a new host for A. dissimile, and also the first record of this tick species infesting lizards of the family Teiidae in Brazil.Keywords: Amblyomma dissimile, tick, Teiidae, Ameiva ameiva, Brazil. Amblyomma dissimile Koch 1844 is an ectoparasite commonly found on amphibians and reptiles. This parasite is widely distributed across several countries in the Americas, including some states in Brazil (Acre, Amazonas, Pará, Roraima, Pernambuco, Mato Grosso do Sul, Mato Grosso, and São Paulo) (ARAGÃO, 1936;SCHUMAKER;BARROS, 1994;ONOFRIO, 2007;DANTAS-TORRES et al., 2008). Records of natural tick infestation of lizards in Brazil are rare because most published reports available in the literature on parasitism focus on either snakes or on laboratory experiments (SCHUMAKER; BARROS, 1994;FREITAS et al., 2004). At present, only two species of lizards have been reported to be infested by A. dissimile in Brazil, namely, adults from Iguana iguana (FREITAS et al., 2004) and nymphs from Tropidurus hispidus (DANTAS-TORRES et al., 2008). ResumoThe teiid lizard Ameiva ameiva is widely distributed in the Neotropics, occurring from Panama to central Brazil (SCHWARTZ; HENDERSON, 1991 apud SARTORIUS et al., 1999. This species of lizard inhabits areas ranging from the Amazonian rain forest to the savanna of Cerrado and the semi-arid region of Caatinga (VITT; COLLI, 1994). Even as a medium-sized lizard, it has fast movements and is an active forager that feeds on a variety of arthropods and vertebrates (VITT; COLLI, 1994). The objective of this study is to report the occurrence of A. dissimile parasitizing the lizard A. ameiva in the state of Maranhão, Northeastern Brazil.A specimen of A. ameiva was collected in an area of Cerrado belonging to the Universidade Federal do Maranhão (05° 44' S and 43° 10' W) in the municipality of Chapadinha, Maranhão. The lizard was visually examined for the presence of ectoparasites (Figure 1a). An engorged adult female tick and two larvae were found, collected manually and preserved in identified bottles containing 70% ethanol. The ticks were analyzed and identified with the aid of a stereomicroscope and according to the dichotomous keys of Aragão e Fonseca (1961) and Onofrio et al. (2006). The adult tick was identified as A. dissimile (Figure 1b) and the two larvae as Amblyomma sp.Most of the studies on infestations of reptiles in Brazil concern the Amblyomma rotundatum, another parasite of "cold-blooded" animals that is well established in the country (ONOFRIO et al., 2006). This tick has been reported to be a parasite of A. ameiva (ONOFRIO, 2007), but data about the location were not reported. According to Pontes et al. (2009), data on A. dissimile ISSN 0103-846X (impresso) / ...

The aim of this paper is to present a study and promote reflections on the contributions and challenges of Pedagogy of Alternation in a Rural Education Degree Course, with a focus on Natural Sciences. For the development of the research, data were collected through questionnaires and from the analysis of the Course’s documents. The results showed contributions of Pedagogy of Alternation, which opens the possibility of graduates entering and continuing in university studies, and brings teachers and students closer to their communities. Challenges were also pointed out, such as the financial burden on undergraduates and the Course to cover housing expenses and cover transportation and food expenses; exhaustiveness and little use in University Time; the need for the graduates to get closer to the university environment and life during the Community Time; the importance of the adherence of the professors to teaching methodologies that are linked to the principles and foundations of Rural Education; the realization of integrative alternating; and the promotion of an inter and transdisciplinary Science teaching, aimed at the formation of rural educators.