Aggregative behavior in Subulina octona (Brugüière) (Mollusca, Subulinidae)

The current study aimed to verify the existence of aggregative behavior in Subulina octona (Brugüière, 1789) and to obtain behavioral evidence of chemical mediation of this behavior. We used 150 adult animals allocated in 15 boxes with humus (10 animals per box). In each box we placed four identified plastic disks in an equidistant position. These disks worked as shelters for the animals. In experiment I, 10 animals were put in the middle of each box. After 24, 48, 96, 120, 144, and 168 hours we observed the number of formed aggregations, as well as the position of the aggregates (in each shelter), the number of individual per aggregation and the number of isolated individuals. In order to test the hypothesis of conditioning of disks by chemicals compounds, the experiment II was carried out. All the individuals were transferred to other boxes with humus, three new disks and the disk containing the larger aggregate after the 168 hours of the experiment I (denominated conditioned disk). We verified, after 24 and 48 hours, the number of individuals below the conditioned disk. In experiment I, aggregations were observed in every used box and in every time intervals. In all boxes, there was a significant increase in the number of individuals per aggregation and a reduction in the number of isolated individuals until the end of the experiment (ANOVA, p < 0.005). In experiment II, after 24 hours, six from 15 boxes presented aggregations under the conditioned disk, and after 48 hours, seven boxes presented aggregations under conditioned disk. These were the aggregations with a larger quantity of individuals, which suggests the conditioning of the used disks by some factor, possibly a chemical compound.O objetivo deste trabalho foi verificar a existência de comportamento agregativo na espécie Subulina octona (Brugüière, 1789) e obter evidências da mediação química desse comportamento. Foram utilizados 150 animais adultos, distribuídos em 15 caixas com terra vegetal (10 animais por caixa). Em cada caixa foram colocados quatro discos plásticos identificados, em posição eqüidistante, os quais serviram como abrigos para os animais. No experimento I, foram colocados 10 animais no centro de cada caixa. Após 24, 48, 96, 120, 144 e 168 horas foram observados o número de agregados formados, a posição dos agregados (sob qual abrigo), o número de indivíduos por agregado e o número de indivíduos isolados. No experimento II, todos os indivíduos foram transferidos para outras caixas contendo terra vegetal, três novos discos e o disco que continha o maior agregado após as 168 horas do experimento I (denominado disco condicionado). Foi verificado, após 24 e 48 horas, o número de indivíduos sob o disco condicionado. Em todas as caixas utilizadas e em todos os intervalos de tempo observados no experimento I, houve a formação de agregados. Houve um aumento significativo do número de indivíduos por agregado e uma diminuição do número de indivíduos isolados com o passar do tempo (ANOVA, p < 0,005). No experimento II, após 24 horas, seis das 15 caixas apresentavam agregados sob o disco condicionado, e após 48 horas, sete caixas, sendo esses os agregados com maior número de indivíduos, o que sugere o condicionamento dos discos usados por algum fator, possivelmente um composto químico

Improved silver carbonate impregnation method for rumen ciliate protozoa

This study proposes improvements to the pyridinated silver carbonate impregnation technique in rumen ciliate protozoa in order to provide a standardized impregnation protocol for usable for the largest possible number of species in domestic ruminants. The proposed improvements are based on results obtained from impregnation of oral infraciliature and nuclear apparatus of 36 rumen ciliate species, which are symbionts of domestic ruminants. Compared to established protocols for morphology of rumen ciliates, impregnation of a wider range of genera and species was observed with the proposed protocol. The impregnation time varied according to size, ciliate taxon, or both, varying from shorter (5 minutes) for small entodiniomorphid ciliates (&lt;80 μm) and the genus Dasytricha, to longer (30 minutes) for large entodiniomorphid ciliates (&gt;80 μm) and the genus Isotricha. The proposed protocol is simple and easily reproducible. It is also advantageous for taxonomic, animal science, and ecological studies that aim to inventory the ruminal biota as well as understand the population structure of rumen ciliates and their relationship with the host

Resistência à dessecação em três espécies de moluscos terrestres: aspectos adaptativos e significado para o controle de helmintos

The pulmonates molluscs act as intermediate hosts for several helminth species, parasites of humans and domestic animals.The control of the snails populations by moluscicides substances have been used as a parasite populations control measure. However, the efficient control of parasites by this mean depends on the knowledge of the snails biology and behaviour, as well as the elucidation of abiotic factors influence over these aspects. The aim of this work was to evaluate the resistence to dessication in three land snail species, Subulina octona (Bruguière, 1789); Leptinaria unilamellata (d’Orbigny, 1835) e Bradybaena similaris (Férussac, 1821), submited to a continuous exposition to 35 oC temperature, for 48 hours. The number of dead individuals, the presence of epiphragms and the number of active individuals were verified at 12 hours intervals. The cephalopodal mass retration into the shell was mensured. After 48 hours of exposition, the snails were tranferred to plastic boxes containing moistened humus. The snails behaviour was verified by direct observations. Dead individuals were counted and the time for arousal was observed

Aspectos ecológicos dos nematóides parasitos de Crotalus durissus terrificus Laurenti, 1768 (Ophidia, Viperidae), em Juiz de Fora, Minas Gerais, Brasil

The aim of this work was to evaluate the qualitative and quantitative aspects of the nematode populations and community parasitizing Crotalus durissus terrificus maintained in semi-extensive breeding system, in Juiz de Fora, Minas Gerais, Brazil. For this 12 snakes were sacrificed and their intestine, stomach, lung, heart, liver and kidneys were examined. Among the examined snakes, 66% were found parasitized by at least one nematode species. The recovered nematodes were Kalicephalus costatus costatus and Kalicephalus inermis inermis in the stomach and intestine, Ascaridia sp., Travassoascaris sp., Hexametra sp., Ophidascaris sp. in the intestine and Rhabdias labiata in the lung. In accordance with the prevalence of each species Kalicephalus inermis inermis (58,3%), Kalicephalus costatus costatus (33,3%) and Rhabdias labiata (33,3%) were considerate secondary species, while Ophidascaris sp. (25%), Ascaridia sp. (16,6%), Hexametra sp. (8,3%), Travassoascaris sp. (8,3%), were considerate satellite species

Estimation and projection of probabilistic age- and sex-specific mortality rates across Brazilian municipalities between 2010 and 2030

Background: Small area age- and sex-specific mortality rates are useful measures for population projections, health, economic, and social planning. Mortality rate estimation in small areas can be difficult due the low number of events/exposure. If a country’s mortality registration has problems, such as incomplete information, then estimating mortality rates can be even more difficult. Previous studies in Brazil have combined demographic and statistical methods to overcome these issues. These approaches depend on a gold standard for age-specific mortality rates and do not estimate uncertainties. We estimated age- and sex-specific mortality rates for all 5,565 Brazilian municipalities in 2010, and forecasted mortality rates between 2010 and 2030. Methods: We used the Tool for Projecting Age-Specific Rates Using Linear Splines (TOPALS) and a Bayesian model to estimate age- and sex-specific mortality rates in all Brazilian municipalities in 2010 while incorporating two types of uncertainties: low exposure and incomplete coverage of death counts. We adapted the Lee-Carter model to forecast age- and sex-specific mortality rates between 2010 and 2030 for all municipalities. Results: The proposed methodology was robust in adjusting for the mortality age profile and in estimating mortality rate uncertainties at the municipal level. The forecasted mortality rates indicated a convergence in life expectancy at birth, and variability of age at death across Brazil’s municipalities, with a persistent sex differential. Conclusion: We estimated and forecasted mortality rates in small areas with limited and incomplete death counts, and high mortality heterogeneity. The methodological approach applied could be useful for countries with death data quality problems similar to Brazil. Our results incorporated the main sources of uncertainty in estimating age- and sex-specific mortality rates and could be used as an important input for policy planning at the municipal level