Dry Matter Production of Shoots and Root Density of Two Cultivars of \u3ci\u3eLablab purpureus\u3c/i\u3e (L.) Sweet

This experiment was conducted in green house conditions to evaluate the DM accumulation in the shoots and in the roots of two cultivars of Lablab purpureus (L.) Sweet. A 2x3 factorial (two cultivars and three evaluation dates) was conducted according to a randomized complete block design with four replications, being the cultivars Highworth and Rongai evaluated at 42, 56, and 70 days after seedling emergence (DASE). The results indicated that the cvs. Highworth and Rongai have the same pattern of DM accumulation in the shoots. In the upper layer of the soil (0-0.20 m) it was found 38.83% and 43.64% of the DM accumulated in the roots down to 2.00 m depth, in the cvs. Highworth and Rongai, respectively. In the deepest layer (1.80-2.00 m) it was found 3.02% and 1.5% of the DM accumulated in the roots of the cvs. Highworth and Rongai, respectively. The root density showed a striking decrease upper layer from the soil (0-0.2 m) down to the depth of 0.60 - 0.80 m (from 10.83 to 1.75 cm.cm-3 in the cv. Highworth and from 10.76 to 1.28 cm.cm-3 in the cv. Rongai). At the bottom layer (1.80-2.00 m) the root density values were 0.98 cm.cm-3 and 0.59 cm.cm-3, respectively for the cvs. Highworth and Rongai. The root/shoot ratios were similar in both cvs. and decreased from 42 to 70 DASE showing that the cvs. evaluated had the same dynamics of DM accumulation

Vegetation Dynamics of Campos Under Grazing/Fire Regimes in Southern Brazil

Natural grassland vegetation in Southern Brazil, known as campos, has most likely evolved under a disturbance regime that included fire and grazing (Pillar et al., 1997). Nowadays, the composition of the vegetation of campos is grazing- and fire-dependent (Boldrini et al., 1997). Its importance can be evaluated by the fact that it represents 37 % of the state’s area and provides 77 % of the slaughtered cattle at Rio Grande do Sul (Barcellos et al., 2002). The objective of this experiment was to evaluate the vegetation dynamics of campos under grazing/fire regimes in order to explore the resilience of the vegetation under the regimes studied

Morphogenesis and Defoliation Frequency of Italian Ryegrass (\u3ci\u3eLolium multiflorum\u3c/i\u3e) and \u3ci\u3ePaspalum urvillei\u3c/i\u3e in Lowland under Three Levels of P and K

This trial was conducted to evaluate growth dynamics and defoliation frequency of Italian ryegrass (Lolium multiflorum) and Paspalum urvillei in a lowland area under three levels of P and K. Using randomization tests we observed that, in a general way, fertilizer treatments were not the determinant factors of leaf appearance and elongation rates for both species. Only the leaf appearance rate of Paspalum urvillei at 100 % of recommendation level and the elongation rate for Italian ryegrass, in the same treatment, was different. Probably other factors, like drainage, are contributing to these results. I. ryegrass phyllochron ranged from 57.3 to 72.6 degree-days. Paspalum urvillei presented higher grazing frequency in almost all evaluated periods, revealing a high preference by the grazing animals

Production Per Animal and Use of Intake Estimatives to Predicted Animal Productivity in \u3cem\u3ePennisetum Purpureum\u3c/em\u3e cv. Mott and \u3cem\u3eCynodon\u3c/em\u3e spp cv. Tifton 85 Pastures

Dairy production is a very important activity in southern Brazil, being an essential source of income to small household farms. Milk production from pastures is an alternative to reduce costs in dairy systems. Some C4 grasses, such as dwarf elephant grass (DEG) and Tifton 85, have presented high animal production per animal and per area. Although studies evaluating milk production from these pastures are rare in south Brazil, in vitro studies have demonstrated that the nutritional value of these forages is higher than production registered in grazing. So, it is possible that, in spite of a high intrinsic nutritional value, limitation on cows’ productivity is linked to the food’s capacity of conversion to milk and/or management conditions that limit forage intake. Leaf mass in pastures is a factor that determinates forage intake, as cows prefer leaf to other parts of plants. In this context, adequate animal performance may be possible if offered enough leaf biomass at pasture. The aim of this experiment was to evaluate the potential of milk production with these two forage species

Meat quality in ewes submitted to reduction in water supply.

The aim of this study was to evaluate the reduction in water supply (ad libitum intake - 100%, or 80%, 60% and 40% of ad libitum intake) on the proximate composition, physicochemical properties, mineral composition and fatty acid profile of ewe meat. Thirty-two crossbred Santa In?es ewe (n = 8 per treatment) were distributed in a randomized block design, receiving a diet consisting of elephant grass and concentrate (70:30). The experimental period lasted 63 days, preceded by 14 days of adaptation. Ewes were slaughtered at the end of experimental period, at a mean final body weight of 37.63 kg. Carcasses were cut lengthwise and the loin (longissimus lumborum) was taken of the left half carcass to evaluate the proximate composition, the physicochemical characteristics, the minerals content and fatty acid profile. The reduction in water supply resulted in a quadratic effect for resilience (p < 0.05), Lightness L* (p < 0.05), potassium (p < 0.05) and iron content (p < 0.001). There was a decreasing linear effect for magnesium content (p < 0.05), copper content (p < 0.001), C18:1n7t content (p < 0.05) and &#931;monounsaturated content (p < 0.05). Crossbred Santa In?es ewe tolerate water restriction up to 40% voluntary intake without compromising the meat quality

Suplementos energéticos para recria de novilhas de corte em pastagens anuais: desempenho animal.

RESUMO - Foi avaliado o desempenho de novilhas de corte dos três aos doze meses de idade, mantidas em pastagem cultivada logo após o desmame (experimento 1) e no primeiro inverno pós-desmame (experimento 2), com ou sem o fornecimento de suplementos energéticos. No período de 16/02 a 21/04/2001, as novilhas permaneceram em pastagem de milheto, exclusivamente sob pastejo (PAST1), suplementadas com grão de milho moído (PAST1/M) ou com polpa cítrica peletizada e moída (PAST1/P). No período de 13/07 a 09/10/2001, as novilhas foram mantidas em pastagem de aveia preta e azevém, sem suplementação (PAST2), suplementadas com grão de milho moído (PAST2/M) ou suplementadas com casca de soja (PAST2/C). Peso vivo (PV), ganho de peso diário médio (GDM) e escore de condição corporal (ECC) foram avaliados. No experimento 1, os animais suplementados apresentaram maior PV final, GDM e ECC que os não-suplementados, não diferindo entre si. No experimento 2, as novilhas suplementadas com casca de soja apresentaram maior GDM e PV final que as não-suplementadas, enquanto as suplementadas com grão de milho ficaram em posição intermediária. O maior ECC foi obtido pelos animais de PAST2/C, seguidos de PAST2/M e, por último, de PAST2. Novilhas de corte desmamadas aos 60- 90 dias devem ser suplementadas no período inicial pós-desmama, para que atinjam desenvolvimento satisfatório nesta fase do crescimento. Os subprodutos polpa cítrica e casca de soja podem substituir o grão de milho como suplementos energéticos para recria de novilhas de corte