Correlation between the nematode egg count of bovine faecal samples and the worm burden in the region of Campinas, State of São Paulo, Brazil

O experimento foi realizado no período de março de 1980 a fevereiro de 1984, na Estação Experimental de Campinas do Instituto Biológico. Foram necropsiados dois bovinos por mês, com idades variáveis, um deles de quatro a dez meses e o outro de seis a dez anos. Esses animais eram separados em baias cimentadas por um período de 30 dias, quando sofriam desvermifugação. Após, eram colocados com o rebanho da propriedade por mais 30 dias. Findo esse tempo, eram levados a outra baia cimentada e permaneciam por cerca de 20 a 25 dias, quando se retiravam fezes diretamente do reto, para as contagens de ovos por grama e após sacrificados e necropsiados para a retirada e contagem do número total de helmintos gastrintestinais presentes. Com os resultados obtidos, concluiu-se que não há correlação significante a nível de 5% de probabilidade, entre a contagem de ovos de helmintos gastrintestinais por grama de fezes de bovinos e a carga parasitária desses animais no período estudado, na região de Campinas, Estado de São Paulo.The experiment was conducted from March, 1980 to February 1984, at the Experimental Station of Campinas. Two animals a month were necropsied, one four to ten months old and the other six to ten years old. Those animals were housed in pen with cemented floor, for one month, when they were treated with a broad spectrum anthelmintic. Thereafter the animals were put to graze in contamined pasture for one month. After remove from pasture, the animals were maintained under worm free conditions for 20 to 25 days, when faecal samples for nematode egg counts were collected and counted for determination of the worm burden. Based on the data, the authors concluded that no have significant correlation, at a rate of 5% of probability, between the faecal nematode egg counts and the worm burden of those animals in the period studied, in the region of Campinas, State of São Paulo, Brazil

Flow cytometric determination of genome size in European sunbleak Leucaspius delineatus (Heckel, 1843)

The aim of this study was to compare DNA content in hepatocyte and erythrocyte nuclei of the European sunbleak, Leucaspius delineatus, in relation to nuclear and cell size by means of flow cytometry and fluorescence microscopy. The DNA standards, chicken and rainbow trout erythrocytes, were prepared in parallel with both cell types, with initial separation of liver cells in pepsin solution followed by cell filtering. Standards and investigated cells were stained with a mixture of propidium iodide, citric acid, and Nonidet P40 in the presence of RNAse, and fluorescence of at least 50,000 nuclei was analyzed by flow cytometry. Average cell size was determined by flow cytometry, using fresh cell suspension in relation to latex beads of known diameter. The size of nuclei was examined on the basis of digital micrographs obtained by fluorescence microscopy after nuclei staining with DAPI. The sunbleak’s erythrocyte nuclei contain 2.25 ± 0.06 pg of DNA, whereas the hepatocyte nuclei contain 2.46 ± 0.06 pg of DNA. This difference in DNA content was determined spectroscopically using isolated DNA from the two cell types. The modal diameters of the erythrocytes and hepatocytes were estimated to be 5.1 ± 0.2 and 22.3 ± 5.0 μm, respectively, and the corresponding modal dimensions of their nuclei (measured as surface area) were 15.2 and 21.4 μm2, respectively. The nucleoplasmic index, as calculated from diameters estimated from surface area of nuclear profiles, was 2.51 for the erythrocytes compared with 0.08 for hepatocytes

Abstracts

Tradução, para a língua inglesa, dos resumos dos artigos publicados nesta edição