Reproductive characteristics of stallions during the breeding and non-breeding season in a tropical region

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Effect of Season on Semen Characteristics and Freezability in Bos indicus and Bos taurus Bulls in the Southeastern Region of Brazil

The objectives of this study were to evaluate the effects of season in southeast of Brazil comparing genotypes on semen characteristics, freezability and peripheral plasma concentrations of testosterone. Ejaculates of five Bos indicus bulls and six Bos taurus bulls were evaluated over a period of 27 months, which was divided into winter (July, August, September), spring (October, November, December), summer (January, February, March) and autumn (April, May, June). Semen was evaluated according to standard procedures for ejaculate volume, sperm concentration, gross-motility, progressive motility and sperm morphology. After preparing and freezing the ejaculates according to commercial procedures, the straws were stored in liquid N(2) until post-thaw evaluation. Ejaculate volume, sperm concentration, gross-motility, progressive sperm motility, vigor and morphological sperm defects were significantly influenced by season and genotype (p < 0.05). Heat tolerance was better in B. indicus bulls than in B. taurus bulls characterized by lower values of sperm abnormalities throughout the observation period. The highest values were recorded for abnormal heads followed by cytoplasmatic droplets in B. taurus bulls. The proportion of ejaculates which were eliminated before freezing for reasons of bad quality was lower in the B. indicus bulls. Temporal changes in peripheral plasma testosterone concentrations were higher in B. indicus bulls than in B. taurus bulls not revealing seasonal influences. The results of this study show clear genotype differences regarding semen quality. Freezability of B. taurus semen varies considerably throughout the year, leading to a high proportion of eliminated ejaculates. Collecting semen from B. taurus bulls during the summer in an artificial insemination centre may not be profitable.

Viral etiology among the elderly presenting acute respiratory infection during the influenza season

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Population structure and breeding season of the South Atlantic hermit crab, Loxopagurus loxochelis (Anomura, Diogenidae) from the Ubatuba region, Brazil

A population of Loxopagurus loxochelis was studied in terms of seasonal abundance, size frequency distribution, sex ratio, and reproductive period (percentage of ovigerous females). Specimens were collected monthly over a period of two years (from September 1995 to August 1997) in the non-consolidated areas of the Ubatuba, Mar Virado, and Ubatumirim bays (northern coast of São Paulo State, Brazil) with a double-rig trawl net. A total of 1,084 individuals were analysed. Animal size (minimum, maximum, and mean +/- SD shield length) was 2.8, 9.1, and 6.88 +/- 1.13 mm for 625 males; 2.8, 8.2, and 5.78 +/- 0.98 mm for 236 non-ovigerous females; and 4.6, 8.0, and 6.24 +/- 0.68 mm for 223 ovigerous females, respectively. Sexual dimorphism was recorded by the presence of males in the largest size classes. The sex ratio was 1.4 : 1 in favour of males. The highest incidence of ovigerous females occurred during winter and spring (June to October), with a low percentage in summer and fall (November to May), indicating continuity in the reproductive cycle. This strategy of reproduction is related to temperature. The occurrence of L. loxochelis in the Ubatuba region represents the final point of northern distribution of this species as a function of water mass influence, and could be its real limit on the Atlantic coast of South America.

Breeding season of the hermit crab petrochirus diogenes (anomura : diogenidae) in the north coast of São Paulo state, Brazil

Petrochirus diogenes, one of the largest hermit crabs in the western Atlantic, was studied in the north coast of the State of São Paulo, Brazil, to determine its breeding season through the analysis of gonad development at a macroscopic level. The analysis of 999 crabs collected from 1995 to 1999, based on four categories of gonad development, showed that males present gonads in the advanced stage during all seasons, and although females present developed ovaries all year as well, the peak incidence is in the summer. The peak of recruitment occurs in the winter.

Comparative gas exchange performance during the wet season of three Brazilian Styrax species under habitat conditions of cerrado vegetation types differing in soil water availability and crown density

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of season, temperature, and body mass on the standard metabolic rate of tegu lizards (Tupinambis merianae)

This study examined how the standard metabolic rate of tegu lizards, a species that undergoes large ontogenetic changes in body weight with associated changes in life-history traits, is affected by changes in body mass, body temperature, season, and life-history traits. We measured rates of oxygen consumption ((V) over dot o(2)) in 90 individuals ranging in body mass from 10.4. g to 3.75 kg at three experimental temperatures ( 17 degrees, 25 degrees, and 30 degrees C) over the four seasons. We found that standard metabolic rate scaled to the power of 0.84 of body mass at all experimental temperatures in all seasons and that thermal sensitivity of metabolism was relatively low (Q(10) approximate to 2.0-2.5) over the range from 17 degrees to 30 degrees C regardless of body size or season. Metabolic rates did vary seasonally, being higher in spring and summer than in autumn and winter at the same temperatures, and this was true regardless of animal size. Finally, in this study, the changes in life-history traits that occurred ontogenetically were not accompanied by significant changes in metabolic rate.

Liver Anatomy, Histochemistry, and Ultrastructure of Eupemphix nattereri (Anura: Leiuperidae) During the Breeding Season

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Contribution of sugar-cane harvesting season to atmospheric contamination by polycyclic aromatic hydrocarbons (PAHs) in Araraquara city, Southeast Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Between-season attraction of cotton boll weevil, Anthonomus grandis Boh. (Coleoptera: Curculionidae) adults by its aggregation pheromone

O presente estudo teve como objetivo investigar a atratividade do bicudo do algodoeiro ao seu feromônio de agregação em período de inverno. Foram utilizados dois campos experimentais no município de Casa Branca, SP. em cada um destes, foram estabelecidas três áreas separadas de aproximadamente 500 metros, sempre próximas à vegetação de refúgio. Cada área foi dividida em três sub-áreas ou blocos de 100 m² para receber a aplicação do feromônio (2,5 g por bloco). Foi realizada uma contagem de bicudos adultos no solo antes, e mais cinco após a aplicação de feromônio. em cada bloco, foram observadas dez parcelas aleatórias, para a avaliação dos bicudos. Os adultos de A. grandis foram atraídos imediatamente após a aplicação do feromônio, sendo capturados por mais de 14 dias após. O índice mais elevado de atração foi observado 24 horas após a aplicação. A utilização do feromônio de agregação durante o inverno, pode aumentar a ação reguladora exercida pelos inimigos naturais, devido ao aumento de disponibilidade de presas. Controle químico pode ser recomendado 24 horas após a aplicação de feromônio em pequenas parcelas, como uma estratégia para a supressão de adultos de Anthonomus grandis em período de entressafra.

Morphogenetic and tillering dynamics in Tanzania grass fertilized and non-fertilized with nitrogen according to season

The objectives of this study were to evaluate morphogenetic characteristics and tillering dynamics in Tanzania grass fertilized and non-fertilized with nitrogen, under intermittent grazing, in the spring and the summer. The main plots were composed of four nitrogen rates (0, 100, 200 and 300 kg/ha) and the subplots were growth seasons: spring (October, November and December) and summer (January, February and March). The experimental design was of randomized block with plots subdivided by time (seasons of the year) and four replications. Urea was used as nitrogen supply and was divided into two applications: one in the spring and another in the summer. The experimental units fertilized with N rates of 200 and 300 kg/ha showed six cycles of pasture, with an average of 27 days of pasture interval, while the treatments with no fertilization and 100 kg/ha of N showed only four and five cycles of pasture, respectively. Leaf elongation rate (LER) and the leaf appearance rate (LAR) increased linearly with increasing of N rates. The greatest population density occurred in summer with the higher nitrogen rates. The treatment without N fertilization showed the lowest growth of tiller population, while the other treatments exhibited growth rates above 50% when compared with non-fertilized samples. Nitrogen rates significantly affect the leaf appearance rate and the leaf elongation rate, as well as the number of live leaves in plants of Tanzania grass in both spring and summer.

Quality of the forage apparently consumed by beef calves in natural grassland under fertilization and oversown with cool season forage species

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Addition of Ca-compounds nanoparticles in melt-textured Bi : 2212

Superconducting BSCCO samples made by melt-texturing process were prepared with the addition of calcium zirconate and calcium silicate nanoparticles. Bi:2212 melt-textured composites prepared with I wt.% of either addition showed different behavior for the critical current density as a function of the applied field, indicating that for each additional compound the improvement can be associated to different enhancement mechanisms, such as the creation of pinning centers and the increase on the connectivity of the grains. The estimated pinning forces indicated higher values for the calcium compound containing samples. (c) 2007 Elsevier B.V. All rights reserved.