Desempenho de novilhos de corte em pastos de capim-tanzânia sob quatro alturas de desfolha

This study was carried out to evaluate the effects of four grazing heights under continuous stocking of Tanzânia grass (Panicum maximum Jacq. Cv. Tanzânia) on the stocking rate, performance and beef production per hectare. The experimental area was 12 hectares, divided into paddocks with one hectare each, with three replicates each (20, 40, 60 and 80 cm). There were three male Nellore bovines per paddock, adding animals as needed to adjust the desired heights in a completely randomized design. The stocking rate had a negative linear function of grazing heights in all seasons regarding yield per hectare, while the average daily gain showed opposite behavior. Apparently, Tanzânia grass heights between 40 and 60cm under continuous stocking enable good average daily weight gain in beef cattle, and high yield per hectare.

Comportamento ingestivo de bovinos mantidos em pastos de Brachiaria brizantha cv. Xaraés manejado em diferentes alturas de pastejo

This experiment was conducted to evaluate the effect of grazing heights on daytime behavioral activities of Nellore beef cattle in the rainy season. The experimental area was 12 hectares divided into paddocks of one hectare each. The treatments consisted of four defoliation heights (15, 30, 45 and 60 cm) in pastures of Brachiaria brizantha cv. Xaraes with three replicates each. It was used the continuos grazing method, with variable stocking rate. Forage samples collected on the plots were sent to the laboratory for separation of the botanical components, weighing and determination of dry matter, with the material collected by simulated grazing. The variables: grazing time, idle time and ruminating time were evaluated for 12 consecutive hours on days 15 and 16 February 2011, considering the morning and afternoon periods. It was used a completely randomized design. The height of the canopy significantly influenced the daily grazing time and ruminating time, with a quadratic response as a function of time of defoliation. The bite rate decreased as a function of heights studied. However the chemical composition of the material collected by simulated grazing did not differ between treatments. Xaraes grass swards grazed at around 45 cm height provide greater ease of apprehension by grazing cattle.

Produção de forragem e composição estrutural de pastos de Brachiaria brizantha cv. Xaraés manejados em diferentes alturas de pastejo

The objective of this study was to analyze the production of dry mass, forage accumulation rate and the structural composition of Brachiaria brizantha cv. Xaraes pastures, managed under different grazing heights in continuous stocking. The experimental area was 12 hectares, divided in paddocks of one hectare each. The treatments were 15, 30, 45 and 60 cm of defoliation heights. Nellore steers were used to reach the desired heights. Every 28 days four cut samples and eight visual samples were collected for comparative performance in the experimental plots. Two grazing exclusion cages were used per treatment to estimate accumulation rates kg.ha(-1) DM. The cut material was taken to the laboratory for separation of the botanical components (green leaf, stem and senescent material), weighing and determination of dry matter. The experimental design was the completely randomized with three replicates. There were treatments effects at all seasons for the production of total mass, except in the spring. In summer and spring seasons it was observed the highest values for leaf blades (1.100 kg DM.ha(-1)). In the winter, the highest values of senescent material was observed, as expected. The average accumulation showed no significant difference among the treatments, except for stem and total mass in the summer and stem in the fall. The tillers were heavier and higher values for number of green leaves per tiller occurred in the fall, but for senescent leaves per tiller ocurred in the winter. Swards grazed at heights between 45 and 60 cm of defoliation, had good production of forage mass and leaf constituent.

Características produtivas e morfológicas do capim Tanzânia em diferentes intensidades de pastejo

The objective of this study was to determine the best height of the Tanzania grass under grazing, assessing morphological and productive characteristics of the sward. This experiment was conducted in Cidade Gaucha, Parana, where he was rated the accumulation rate and morphological characteristics of Tanzania grass pastures grazed at 20, 40, 60 and 80 cm grazing under continuous stocking with variable stocking rate for beef cattle. The experimental area was 12 hectare divided in paddocks of one hectare each. For each paddock were allocated two grazing exclusion cage for estimating herbage accumulation, and eight samples were taken every 28 days throughout the year 2010. The completely randomized design. The herbage mass of the morphological structures showed a linear positive function of sward heights. The height of defoliation did not influence the rate of herbage accumulation for any of the morphological structures: green leaf, stem + sheaths and senescent material. There were also no differences in leaf: stem ratio. All heights within the range studied provided adequate number of green leaves per tiller. Tanzania grass pastures grazed under continuous stocking between 40 and 60 cm, for providing a good association between accumulation and mass of green leaf blades, and acceptable values of the mass of stem + sheaths and senescent material. Pasture of Tanzania grass under 60 and 80 cm allow of leaves satisfactory accumulation in the autumn.

Tubo digestório de Urostreptus atrobunneus (Diplopoda): estrutura e função

Millipedes are macro-arthropods of soil which perform a important role in maintaining the balance of the ecosystem, since they feed on decaying organic matter and because they promotes the soil enrichment, aeration and humidification. These animals are usually found in humid with low light places, under rocks and trunks. The diplopods exoskeleton is much resistant and impregnated with calcium salts. Due the secretion of defense, with strong and unpleasant smell, the animals of this class have few or no predators. Large diplopods populations are not observed, but explosions population can occur for unbalances enviromnmental, by climate change and by use of pesticides that may eliminate potential competitors. In this sense, the millipede Urostreptus atrobrunneus Pierozzi & Fontanetti, 2006, has presented points of infestation in urban centers of Sao Paulo state, causing many disorders of the human population. Because it is a newly described species, little is known of its aspects biological and morphological. Thus, the purpose of this study was to describe the structure and function of the digestive tract of the species U. atrobrunneus by means of histological, histochemistry and ultrastructural techniques. The results demonstrated that the digestive tract of U. atrobrunneus is similar to the descriptions given for other species. The foregut consists of a simple epithelium, composed of cells of different heights, covered by a cuticular intima, leaning on a thin basal membrane, followed by a well-developed muscular layer and an external membrane, around the foregut have a pair of salivary glands. The midgut epithelium has a pseudostratified, supported by a thick basal membrane, followed by a muscular layer and a layer of hepatic cells. The muscle is distributed unevenly coated with an external membrane, this portion is marked by the absence of cuticular intima... (Complete abstract click electronic access below)

Eficiência nutricional da dieta de novilhos de corte mantidos em pastagem associada a suplementação

Pós-graduação em Zootecnia - FCAV

Variabilidade no andar com ultrapassagem de obstáculo de idosos com doença de Parkinson

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

Canopy characteristics and behavior of Nellore heifers in Brachiaria brizantha pastures under different grazing heights at a continuous stocking rate

The objective of this study was to evaluate the Brachiaria brizantha cv. Marandu canopy structure maintained at different grazing heights under a continuous stocking rate and with a dietary supplementation strategy for the animals during the rainy season. This study also intended to observe the relationships of these variables with the grazing behaviors of the heifers. The effects of three canopy heights (15, 25 and 35 cm) were evaluated in association with three types of supplements: one mineral and two protein/energy supplements, the first with a high rumen degradable protein and energy and the others with a low ratio. Both the protein/energy supplements were provided at 0.3% of body weight/day. The experimental design was completely randomized, with two replications and repeated measures, and took place during the period from January to April 2008. The supplementation strategies did not affect any variable related to the canopy structure. Total and green herbage masses and the ratio of green/dead material increased with canopy height. The leaf/stem ratio was higher in the lowest canopy height: 15 cm. Changes in the canopy structure caused variations in the grazing behavior of the animals. Animals maintained in the 15-cm-tall pasture grazed for a longer time, increasing the time for each meal, but the number of meals was lower than that of the animals grazing within the 35-cm-tall pasture. The grazing time of animals receiving the energy/protein supplement was lower only in the period of the day during which it was supplied. Canopy structure is affected by sward height, and changes animal behavior. Supplementation does not affect the canopy structure of the pastures with similar heights.

Evaluation of corn cultivars harvested at two cutting heights for ensilage

Objetivou-se neste estudo avaliar as características agronômicas, a composição químico-bromatológica e a digestibilidade de 11 cultivares de milho (Zea mays) colhido em duas alturas de corte. As cultivares D 766, D 657, D 1000, P 3021, P 3041, C 805, C 333, AG 5011, FO 01, CO 9621 e BR 205 foram avaliadas quando colhidas 5 cm acima do solo (baixa) e 5 cm abaixo da inserção da primeira espiga (alta). O experimento foi delineado como blocos casualizados, com três repetições, arranjados em esquema fatorial 11 x 2. Os cultivares apresentaram produções semelhantes de matéria seca de forragem e de grãos. As porcentagens das frações colmo, folha, palha, sabugo e grão diferiram entre os cultivares, assim como os teores de matéria seca da planta inteira no momento da colheita. Considerando a planta inteira, apenas os teores de energia bruta, nitrogênio da fração fibra em detergente neutro e a digestibilidade in vitro da fibra em detergente neutro e detergente ácido não diferiram entre os cultivares. O aumento da altura de corte melhorou a qualidade da forragem, devido à redução das frações colmo e folha e dos teores dos constituintes da parede celular.

Nutritional characteristics and in vitro digestibility of silages from different corn cultivars harvested at two cutting heights

Objetivou-se neste estudo avaliar as características nutricionais e a digestibilidade in vitro de silagens de diferentes cultivares de milho colhidas em duas alturas de corte. Foram avaliadas 11 cultivares (Dina 766, Dina 657, Dina 1000, P 3021, P 3041, C 805, C 333, AG 5011, FO 01, Dina co 9621 e BR 205) colhidas 5 cm acima do solo (baixa) e 5 cm abaixo da inserção da primeira espiga (alta). O experimento foi delineado em blocos casualizados (três blocos), arranjados em esquema fatorial 11 × 2. As silagens das plantas colhidas na altura de corte alta apresentaram teor médio de matéria seca significativamente superior às silagens das plantas colhidas na altura de corte baixa. As cultivares FO 01, AG 5011, Dina co 9621 e Dina 766 apresentaram maior teor de proteína bruta, que as cultivares C 805, P 3041 e P 3021, as quais apresentaram os menores teores deste nutriente. A elevação da altura de corte aumentou os coeficientes de digestibilidade verdadeira in vitro da matéria seca e digestibilidade in vitro da matéria seca das silagens avaliadas. O aumento da altura de corte melhorou o valor nutritivo das silagens, diminuindo as concentrações das frações fibrosas e aumentando a digestibilidade in vitro da matéria seca.

Bromatological evaluation of eleven corn cultivars harvested at two cutting heights

The objective of this study was to evaluate the chemical composition and dry matter in vitro digestibility of stem, leaf, straw, cob and kernel fractions of eleven corn (Zea mays) cultivars, harvested at two cutting heights. The experiment was designed as randomized blocks, with three replicates, in a 2 × 11 factorial arrangement (eleven cultivars and two cutting heights). The corn cultivars evaluated were D 766, D 657, D 1000, P 3021, P 3041, C 805, C 333, AG 5011, FOR 01, CO 9621 and BR 205, harvested at a low cutting height (5 cm above ground) and a high cutting height (5 cm below the first ear insertion). Cutting height influenced the dry matter content of the stem fraction, which was lower (23.95%) in plants harvested at the low, than in plants harvested at the high cutting height (26.28%). The kernel fraction had the highest dry matter in vitro digestibility (85.13%), while cultivars did not differ between each other. Cob and straw were the fractions with the highest level of neutral detergent fiber (80.74 and 79.77%, respectively) and the lowest level of crude protein (3.84% and 3.69%, respectively). The leaf fraction had the highest crude protein content, both for plants of low and high cuttings (15.55% and 16.20%, respectively). The increase in the plant cutting height enhanced the dry matter content and dry matter in vitro digestibility of stem fraction, but did not affect the DM content of the leaf fraction.

Influence of Crown Ferrule Heights and Dowel Material Selection on the Mechanical Behavior of Root-Filled Teeth: A Finite Element Analysis

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

Fracture resistance of endodontically treated teeth with different heights of crown ferrule restored with prefabricated carbon fiber post and composite resin core by intermittent loading

This study evaluated the fracture resistance of endodontically treated teeth restored with prefabricated carbon fiber posts and varying quantities of coronal dentin. Sixty freshly extracted upper canines were randomly divided into groups of 10 teeth each. The specimens were exposed to 250,000 cycles in a controlled chewing simulator. All intact specimens were subjected to a static load (N) in a universal testing machine at 45 degrees to the long axis. Data were analyzed by 1-way analysis of variance and Tukey test (alpha = .05). Significant differences (P < .001) were found among the mean fracture forces of the test groups (positive control, 0 mm, 1 mm, 2 mm, 3 mm, and negative control groups: 1022.82 N, 1008.22 N, 1292.52 N, 1289.19 N, 1255.38 N, and 1582.11, respectively). These results suggested that the amount of coronal dentin did not significantly increase the fracture resistance of endodontically treated teeth restored with prefabricated carbon fiber post and composite resin core. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;106:e52-e57)