Mércia Virginia Ferreira dos Santos

Produtividade e composição química de gramíneas tropicais na Zona da Mata de Pernambuco

This work was carried out to evaluate the productive potencial and chemical composition of five grasses (Pennisetum purpureum Schum. cv. Pioneiro, P. purpureum Schum cv. Mott; Panicum maximum Jacq. cv. Mombaca, P. maximum Jacq cv. Tanzânia, e Brachiaria brizantha (Hochst) Stapf. cv. Marandu). The cuts were performed at 35 days of intervals and 40 cm above ground. Pioneiro showed higher DM yield (7.35 t DM/ha/35 days) when compared to the Dwarf Elephantgrass (5.28 t DM/ha/35 days) and Tanzânia grass (5.23 t DM/ha/35 days), being similar to the others. Brachiaria brizantha presented the highest total tillering (538.72/m²) however the aerial tiller weight was the lowest for this species. The cultivars of P. purpureum showed higher aerial tillering and lower basal tillering, when compared to the cultivars of P. maximum. The CP concentration ranged from 6.96 to 10.20% and the cultivar Pioneiro presented the highest value. No difference was found among the forages for NDF and ADF, and the mean values were 73.83 and 39.20%, respectively. At the evaluated cut interval, the forages presented a high proportion of leaves (> 80%), showing potential to be used on livestock pasture-based operations in the Forest Zone of Pernambuco.

Caracterização da vegetação de Caatinga e da dieta de novilhos no Sertão de Pernambuco

O objetivo deste trabalho foi avaliar a composicao botânica, a disponibilidade e a qualidade da forragem e da dieta de animais fistulados alimentados na Caatinga, no periodo chuvoso, em Pernambuco. Avaliaram-se a composicao botânica e a disponibilidade de fitomassa dos estratos herbaceo, arbustivo e arboreo, nos meses de marco e junho. A avaliacao da qualidade da forragem foi feita por meio da analise bromatologica, realizada em todos os meses do periodo chuvoso. Foram encontradas 67 especies, das quais 28 herbaceas, 20 arbustivas e 19 arboreas. Destas, 19 foram encontradas na dieta dos animais. A disponibilidade de fitomassa do componente herbaceo variou de 1.369 kg ha-1 de materia seca (MS), em marco, para 452 kg ha-1 de MS em junho. A disponibilidade do estrato arbustivo aproximou-se do herbaceo, enquanto o componente arboreo contribuiu com apenas 178 kg ha-1 de MS. Apesar de a disponibilidade de fitomassa ser relativamente alta, apenas uma pequena porcentagem do material encontrado pode ser considerada como forragem. Foi observada baixa digestibilidade da proteina, provavelmente em consequencia do alto teor em lignina.

Potential of Caatinga forage plants in ruminant feeding

Caatinga is the most important biome for the livestock in the Brazilian semi-arid region. This review paper aimed to present information on different forage aspects of caatinga vegetation for ruminant feeding. Caatinga vegetation is formed mainly by shrubs and small trees, usually presenting thorns, deciduous leaves, and leaf abscission occurring frequently at the onset of the dry season. Additional components of the botanical composition in this biome includes the families cactaceae, bromeliaceae, and a herbaceous component formed by grasses, legumes, and forbs, often presenting annual cycle. Quantitative information of caatinga vegetation is scarce in the literature, mainly for the herbaceous stratum. Methodological aspects such as lack of standardization across evaluations make comparison regarding forage potential of caatinga plant species difficult. Index species must be identified within each caatinga type. Quantitative aspects of biological N2 fixation by caatinga species have not been extensively studied. Regarding forage nutritive value, it is necessary to study N availability for ruminants in caatinga plants, since large proportion of this element may bind to fiber components (ADIN). Manipulation of caatinga vegetation is an alternative to change forage quantity and quality for grazing animals, affecting their performance as a result. Studies measuring qualitative and quantitative variability of native forage resources from caatinga are mandatory in order to improve animal feeding management, with the ultimate goal of creating sustainable animal production based on caatinga vegetation.

Mineral fertilization effect on growth and chemical composition of cactus pear - clone IPA 20.

The study was carried out in the greenhouse of the “Instituto Agronômico de Pernambuco IPA”, located in Recife – PE. It aimed to evaluate the effects of P and K fertilization on growth and chemical composition of cactus pear IPA-20 clone. Four levels of P (0, 200, 400, and 800 kg P2O5 ha-1) and four levels of K (0, 200, 400, and 800 kg of K2O ha-1) were tested in a 4 x 4 factorial arrangement using a complete randomized block design. Observations were made at 28-d intervals, starting by the third month after planting and lasting until the sixth month of growth. Fresh matter yield of primary articles and total fresh matter yield were affected only by K fertilization (P < 0.05). Concentrations of N, K, Ca, Mg, and S in the cactus shoot were affected by P fertilization (P < 0.05), however, P concentration was not affected. Potassium fertilization affected (P < 0.05) only Ca and S concentrations. Average results for N, P, K, Ca, Mg, and S were 20.62, 4.75, 33.43, 34.43, 7.44, and 6.10 g kg-1, respectively. Fresh matter yield and dry matter concentration were affected only by K fertilization. Micronutrient concentration was not affected by P and K fertilization.

Caracterização e Seleção de Clones de Capim-Elefante (Pennisetum purpureum Schum.) na Zona da Mata de Pernambuco

This work aimed to characterize an elephantgrass collection (Pennisetum purpureum Schum.) comprising 71 clones and selecting the best ones to be tested later under grazing conditions. It was carried out at Cedro Experimental Station - IPA, located in Vitoria de Santo Antao, forest zone of Pernambuco State. The period of evaluation included both the raining and the dry season. Each clone was represented by a non-replicated plot of 10 m2. According to linear correlation analysis, the more productive clones also showed highest plant height and highest growing point height, greatest stem diameter, highest stem/leaf ratio, highest basal and total tiller numbers and greatest leaf lenght. The same characteristics above were also positively correlated with the leaf blade yield, except stem/leaf ratio. There was a high correlation coefficient (r = 0.9517) between dry matter yield and leaf blade yield. The selection of clones to be tested under grazing conditions was based on the materials that showed the highest leaf blade yield. These materials were: Mineirao/IPEACO, Hexaploide, Mole de Volta Grande, King Grass, 591-76 or Cameroon, CE 5 AD, Gigante de Pinda, CE 4 AD, Elefante da Colombia and Vrukwona

Deposição e acúmulo de matéria seca e nutrientes em serapilheira em um bosque de sabiá (Mimosa caesalpiniifolia Benth.)

n Quantification of litter deposition and organic mantle accumulation are important steps on nutrient cycling studies. This study aimed to quantify litter deposition and organic mantle in a sabiAE (Mimosa caesalpiniifolia Benth) woodlot in an experimental farm in the Brazilian northeast region. Twenty 0.50 x 0.50 x 0.15 m wood collectors, to quantify litter deposition, were systematically distributed over the area elevated 30 cm above the soil. Deposited material was collected monthly from October 2000 to September 2001, and separated into leaves, twigs, flowers, pods and mixed portions. Undecomposed organic mantle was randomly sampled nearby collector boxes, to a total of 20 monthly samples, from which a 0.30 x 0.30 m composed sample was collected. The collected material was also hand separated into leaves, twigs, flowers,

Evaluation of botanical composition of sheep diet in Caatinga pasture

This study was carried out to evaluate the effect of cannula placement site and hour of collection on the botanical composition of sheep diet. Ten castrated sheep Santa Ines breed were used, with five of them using permanent ruminal cannula and the five others with esophageal cannula. Water and mineral mix were available ad libitum. Samples collected from both cannulas revealed 39 species with an average of 20 species occurring in each monthly sampling. In addition, other Poaceae species were not identified. There was a significant effect of collection time on the botanical composition and on the plant fractions selected by the sheeps. Leaf was the most consumed fraction, corresponding to 55% of the extrusa sample. Stem proportion was affected by month x hour of collection interaction. There was no effect of the place of fistula or time of collection on botanical composition of the diet, however, the interaction of month of collection, fistula placement and, time of collection affected botanical composition and proportion of plant fractions consumed. The selectivity index varied during the study for several species, being directly related to the ingestive behavior of the sheep. Feed selected by sheep presented a large number of plant species with malvaceae and poaceae being the most important families. Ruminal cannula instead of esophageal cannula can be used to characterize the botanical composition of the diet consumed by small ruminants.

Composição química e degradabilidade in situ da ração em ovinos em área de caatinga no sertão de Pernambuco

This work was conducted with the objective of evaluating the effect of the type of fistula and time of collection on the chemical composition and in situ digestibility of dry matter, neutral detergent fiber and crude protein in the caatinga region. The experiment was conducted between September 2004 and July 2005. Ten Santa Ines castrated sheep, five with permanent ruminal cannula and five with esophageal cannula, were used. Samples were collected from both cannulas at 7:00 am and 2:00 pm. Sheep had free access to water and mineral mix. The percentage of DM, MM, CP, EE, NDF, ADF, NDIP, ADIP, CHOT, NFC, FT, TT and TC ranged from 11.99 to 25.28%; 10.92 to 14.44; 10.64 to 17.19%; 2.95 to 4.77; 54.83 to 63.14%; 39.40 to 46.62%; 49.74 to 57.95; 28.52 to 39.15; 65.40 to 72.73; 5.47 to 12.86%; 0.37 to 0.52%; 0.16 to 0.28%; and from 1.28 to 6.24%, respectively. Potential degradability (%), fraction B (%), fraction C (%/h), fraction A (%), effective degradability and passage rate of 2 and 5%/h ranged from 48.25 to 64.63; 35.77 to 47.78; 4.60 to 13.40; 9.74 to 18.13; 43.28 to 55.71 and 37.60 to 47.27 for dry matter; from 36.43 to 54.34; 33.28 to 50.38; 3.84 to 8.42; 2.16 to 4.41; 29.21 to 36.54; 23.02 to 33.33 for neutral detergent fiber and from 62.13 to 77.24; 35.44 to 56.09; 5.37 to 14.36; 20.21 to 31.49; 55.84 to 67.49; 45.74 to 59.99 for protein, respectively. The chemical composition and in situ digestibilility of diets for sheep in caatinga is influenced by the month of evaluation. The diet for sheep in the caatinga region presented low in situ digestibility of dry matter, neutral detergent fiber and crude protein. Ruminal cannula instead of esophageal cannula can be used to characterize the chemical composition and degradability of diet consumed by small ruminants.

Rendimento e composição químico-bromatológica de fenos triturados de gramíneas tropicais

The research was carried out to evaluate yield, chemical composition and losses of chopped tropical grass hays with the following forages: pearl millet (Pennisetum americanum), sudangrass (Sorghum sudanense), elephantgrass (Pennisetum purpureum) and two cultivars of forage sorghum (SF-25 and IPA-467-4-2) (Sorghum bicolor). The materials were harvested at 30% flowering, except for elephantgrass (60 days). The experiment was conducted according to a complete randomized block design, with five treatments and four replications. There were significant differences among hay productions with sorghum cultivars IPA-467-4-2 and SF-25 reaching the highest yields (10.85 and 10.65 t/ha/cut). Production of elephantgrass, sudangrass and pearl millet hays were respectively of 6.94, 6.69, and 4.93 t/ha/cut. Percentage of hay losses were not different among all treatments and varied from 17.33 to 20.17%. Pearl millet and sudangrass hays had the highest CP concentrations (10.56 and 8.80%), which were superior to elephantgrass (6.76%) and sorghum cultivars (5.62 and 5.50%). Most of the NDF values were superior to 70.0%. Sorghum cultivars exhibited the lowest NDIN concentration (0.42 and 0.40% of DM). The ADIN concentration ranged from 0.06 to 0.30% of DM. The highest lignin (%DM) concentration was observed for pearl millet (6.52%) and sorghum IPA-467-4-2 (6.17%) hays. Estimated TDN of the hays showed significant differences and sudangrass reached the highest value (53.35%). Production of chopped tropical grass hays showed high yields and chemical composition according to the minimum standards for ruminant nutrition.

Distribuição de biomassa e nutrientes na parte aérea de Mimosa caesalpiniaefolia Benth

This work was carried out at Itambe Experimental Station, in the State of Pernambuco, Brazil, to study biomass and nutrient distribution in stands of Mimosa caesalpiniaefolia Benth. Two stands with similar soil and topographical conditions were studied, involving plants eight and eleven years old, at 3.0 x 3.0 m and 4.5 x 4.5 m spacing, respectively. The biomass of each tree component was determined. Samples of leaves, branches, bark and stem were collected and chemically analyzed. Total biomass was 66.22 and 80.78 t/ha in stands I and II, respectively. Biomass distribution in stands I and II was: branches (44.99 and 53.40%), wood (51.53 and 44.58%), bark (2.39 and 1.40%) and leaves (1.10 and 0.62%). Nutrients of the components for both stands showed the following concentration trend: Nitrogen > Calcium > Potassium > Magnesium > Sulfur > Phosphorus.