Avaliação de pastagens tropicais em sistemas de produção de ovinos de corte no nordeste brasileiro

He aim of this study was to evaluate the structural characters, herbage accumulation, nutritive value and performance of sheep in different tropical pastures. The treatments were two cultivars and two of the genera Panicum Brachiaria pastures under intermittent stocking and variable stocking rate, in the rainy season. We evaluated the masses and the components of herbage pre grazing in two layers, and after grazing. Chemical analyzes were made of the stems and leaf blades pre grazing in two layers. We used 48 male sheep and whole for the assessment of individual weight gain and area, and anestrous females to adjust the stocking rate. In the cv. Massai showed the highest herbage mass, leaf blades and dead material, and the largest volume density and leaf blade: stem pre grazing. There was no difference among cultivars for the percentage of leaf blade (PLB) in both strata, but the higher the PLB was higher than the bottom. The highest percentage of dead material (PDM) was observed in cvs. Massai and Marandu in the two strata. In cvs. Massai and Piatã were observed lower levels of crude protein in stem and leaf. In stratum 0-25 cm lower nutritional value was observed in the stem in the leaf blades did not grant the nutritional value among the strata. Herbage mass, leaf blade, PLB and proportion of stem in the residue of the Massai pastures were higher than cv. Aruana. There was no difference for efficiencies in harvest leaf and stem between the cultivars. The cv. Massai got the higher accumulation of leaf per cycle per day. Animals kept in grass swards Aruana had the highest average daily gain. The higher stocking rates and earnings per area were observed in grass swards and Marandu Massai. The cultivars are suitable for sheep meat production in the rainy season

Marcadores fenotípicos para caracterização de caprinos com diferentes níveis de resistência às endoparasitoses gastrintestinais

The aim of this study was to evaluate and characterize phenotypically goats with different levels of resistance to gastrointestinal nematodes. For a period of 93 days, 60 F2 goats originated from ½ Saanen and ½ Anglo- nubian animals were kept in the same area of pasture. Every seven days, feces and blood were collected for eggs per gram counts of feces (EPG) and cultures of feces and to determinate the number of eosinophils, packed cell volume and total plasma protein, respectively. On the same day, the animals were weighed and submitted to body score condition and FAMACHA method to worm control. Based on the average of EPG, the twelve animals with the highest average (susceptible group) and the twelve animals with the lowest average of EPG (resistant group) were selected, slaughtered and necropsied to recovery, counting andparasites identification. The resistant animals present lower EPG mean (P <0.0001) and 4.7 folder less parasites than susceptible animals. The resistant group presented higher mean packed cell volume (26.48%) and total plasma protein (6.24 g / dl) than susceptible one (24,04% e 5,82g/dl, respectively). The average number of eosinophils was similar in both groups The Haemonchus sp. was the most prevalent in the culture of feces, followed by Trischostrongylus sp. and Oesophagostomum sp.. The counting of nematodes in the abomasum of susceptible group was higher than in resistant one. The species identified were H. contortus in abomasums and T. colubriformis in small intestine. It can be concluded that EPG, packed cell volume and total plasma protein were useful phenotypic markers to identify animals as resistant and susceptible to gastrointestinal nematodes infections

Características da carcaça e qualidade da carne de ovinos terminados em pastagens cultivadas

The objective of this study was to evaluate the quality of housing and the physical and chemical characteristics of meat from sheep raised on pasture Brachiaria brizantha and Panicum maximum. The experiment was conducted in the physical area of the Study Group on Forage (GEFOR), located in the Academic Unit Specialized in Agricultural Sciences - Federal University of Rio Grande do Norte - UFRN in Macaíba, RN, Brazil. We used 32 lambs SPRD, obtained from herds in the state, with liveweight (LW) of 24.5 kg were assigned randomly to four treatments consisting of tropical grasses, two cultivars of Brachiaria brizantha, Marandu and Piatã, and two of Panicum maximum, Aruana and Massai. The experimental area was 2.88 ha, divided into 4 paddocks of 0.72 ha, where each picket consisted of a farm and was divided into six plots of 0.12 ha, where the animals remained under rotational grazing. The period of adaptation to the pickets was seven days. At the beginning of the experiment the animals were weighed, identified with plastic earrings and necklaces colored according to the treatment, and treated against. The lambs were loose in the paddock at 8 am and collected at 16 hours, which returned to collective pens. During the time of grazing animals had free access to mineral supplement with monensin Ovinofós ® and water. Before entering the paddocks of pasture were sampled to characterize the chemical composition. Every seven days occurred at weighing, with fasting, to monitor the weight development. Cultivars Marandu, Aruana, Piatã and Massai were grazed for 133, 129, 143 and 142 days, respectively, until the lambs reach slaughter weight. Arriving at 32 kg lambs were evaluated subjectively for body condition score by, passed through fasting period, diet and water for 16 hours were slaughtered. Measurements were made in the inner and outer casings in addition to subjective evaluations regarding muscling, finish and quantity of pelvic-renal fat, then each was divided longitudinally into two half-carcases and cuts were made in the commercial left half, and after heavy calculated their income. Between the 12th and 13th thoracic vertebrae, was performed a cut to expose the cross section of the Longissimus dorsi, which was drawn on the rib eye area (REA) in transparent film. Fat thickness and extent of AOL GR were determined using a caliper. A tissue composition was determined by dissection of the legs. Analyzes were performed physical (color, cooking loss and shear force) and chemical composition of meat (moisture, ash, protein and lipids) in Longissimus dorsi muscle. Grazing tropical grass Brachiaria brizantha cvs. Marandu and Piatã and Panicum maximum cvs. Aruana and Massai can be used for lambs SRPD in the rainy season, because not alter the physico-chemical and chemical composition of meat

Respostas morfogênicas e estruturais de gramíneas tropicais em regime de corte no nordeste brasileiro

The production of forage grasses is directly related to the morphogenesis. The knowledge of the morphogenetic and structural variables of forage plants is important for determining appropriate conditions of grazing livestock to ensure efficient and sustainable. Thus the objective of this study was to evaluate morphogenetic and structural responses of three genera of grasses, Brachiaria, Panicum and Cenchrus in a cutting regime. The experimental design was randomized blocks with three replications and six treatments. After each section were evaluated for forage production, appearance and elongation rates of leaves and stem, phyllochron, final leaf length, number of living leaves, leaf lifespan, leaf senescence rate, tiller density and tiller dynamics. On forage yield the highest values were obtained in cultivars Xaraes, Piata and Massai. The tiller density was higher for cv Massai. It is concluded that the cultivars of Panicum and Brachiaria had a higher tillering dynamics in increasing the turnover rate of tissues that are indicators of forage production, assuming that the cultivars of these genera are predisposed to use forage in the Northeast

Parâmetros parasitológicos e desempenho produtivo de ovinos naturalmente infectados com nematoides gastrintestinais mantidos em diferentes pastagens tropicais

The control of gastrointestinal nematodes of small ruminants is usually done with anthelmintics. However, due to the emergence of ever-increasing parasite resistance to these drugs, looking up an alternative control parasites. One of this is sought in pasture management, as these are the sources of animals` infection by L3 infective larvae of helminths. The aim of this study was to evaluate the performance of sheep to natural infections by gastrointestinal nematodes grazing Panicum maximum cv. Massai and cv. Aruana, and Brachiaria brizantha cv. Piatã and cv. Marandu. The work was conducted from May to August-2011 with 48 male sheeps SRD versus Santa Inês breed. The animals were naturally infected with gastrointestinal nematodes, and maintained in four different cultivars of tropical forage grasses, naturally contaminated with eggs and larvae of gastrointestinal nematodes. Each week the animals were phenotypically characterized by parasitological examinations (eggs per gram of feces - EPG, and feces culture), hematological (packed cell volume PCV, and blood eosinophil count) method to evaluate the Famacha© colorof ocular mucosa, and the measures of body condition score and weight. In pastures was made the recovery of infective larvae in order to determine the quantity of L3 present in the pasture. The experimental design was a randomized completed block with two replications and before the entry of animals in the paddocks, they have been wormed. The experiment was ended when the animals reached 32.0 kg liveweight, and then were slaughtered and autopsies performed for the recovery and identify parasites of the abomasum, small intestine and large intestine. Results were subjected to analysis of variance, t test and Tukey`s test. The animals kept on pastures of Marandu grass had lower EPG counts, higher percentage of packed cell volume and higher average weight; those who remained in the Piatã pasture had lower eosinophil counts per microliter of blood. About the Famacha©, the highest prevalence was Famacha 2, and the body condition score ranged between 2 and 3. The results of feces cultures and recovery of larvae on pastures showed the presence of larvae of Trichostrongylus sp., and at the necropsy too. This way, it was concluded that the grass cultivars influences the sheep parasite load; the Famacha, together with EPG and packed cell volume are important indicators for use in controlling gastrointestinal nematode infections. The Trichostrongylus sp. was the most prevalent parasite in sheep during the rainy season

Produção de ovinos em pastagem de capim-massai suplementados na estação seca

The low quality of tropical pastures in the dry season justifies the use of dietary supplements to meet the nutritional needs of sheep to meat production. Therefore, the objective of this experiment was to evaluate the agronomic characteristics of massaigrass in the dry season and the effect of protein supplements in the performance and productivity of sheep to meat production grazing. The protein supplements evaluated were: soybean meal, Leucena hay, Gliricidia hay and multiple mixture. The animals were managed in massaigrass pastures under rotational stocking and supplemented daily. Were used 24 sheep ½ Santa Inês x ½ SPRD (without defined breed), males uncastrated, mean age 90 days in a completely randomized design. Performance of sheep was evaluated for average daily gain of live weight gain per area and stocking rate (animals of 25 kg/ha). The pasture was evaluated for forage mass of pre and post-grazing, the percentages of participation of morphological constituents and their nutritional values and rates of herbage accumulation. The total herbage mass decreased throughout the dry season. Crude protein and in vitro digestibility of organic matter of the leaf were higher in the upper 15 cm of the canopy stratum. The average daily weight gain of the animals supplemented with legume hay was similar to that gained by animals supplemented with soybean meal in the four grazing cycles. The total live weight gain of animals supplemented with legume hay was higher than the animals supplemented only with multiple mixing the first two grazing cycles. Hays of Leucena and Gliricidia can be given for supplementation of sheep maintained on pasture

Desempenho de novilhos alimentados com dieta suplementar em pastos de capim-mombaça

The objective of this work was to evaluate the effect of supplements feeding on growth of calves grazing a Panicum maximum cv. Mombaça pasture during the dry season. The experimental design was a randomized blocks with three treatments and three replications. The treatments were: mineral salt ad libidum; multiple mixture (MM) fed at 0.2% of live weight (PV); and, concentrate feed (SC) fed at 0.7% of PV. Thirty six weaned calves averaging eight months and 192 kg of initial live weight were utilized. The masses and pasture components, nutritive value and rate of forage growth were evaluated. Animal performance was measured as average daily gain (ADG) and live weight gain (LWG). The supplemental feeding was adjusted after weighing. There was no difference between periods for forage mass and leaf: stem ratio. The highest values for forage green mass, leaf blades mass and stem percentage were observed in the first trial period. The canopy height and the available forage on offer did not differ among treatments. The percentage of dead was higher for the last periods of evaluation. The leaf: stem ratio and the leaf percentage were greater in the second period. There was significant difference (p<0,05) among treatments for the ADG and were 250, 460 and 770 g/day for salt, MM and SC, respectively. The biggest LWG was observed in the treatment SC. contents of PB, DIVMO, NDF and LDA on leaf blades, thatched roofs and dead material dead not differ among treatments. The highest GPV was observed in the SC treatment. The contents of PB, DIVMO, NDF and LDA for leaf blades stem and dead material did not differ among treatments. Independent of the use supplements , it is possible to keep steers gaining weight, during dry season, since the stocking rate is appropriately adjusted

Resposta de ovinos naturalmente infectados por nematoides gastrintestinais em pastos de capim-massai

The aim of this study was to evaluate the crossbred sheep Santa Ines response to natural infections by gastrointestinal nematodes in Panicum maximum cv. pastures Massai at different times of grazing. For this it was used 36 crossbred sheep Santa Inês, divided into four groups and randomly distributed in massai-grass pickets naturally infected by gastrointestinal nematodes. In the period from October 2013 to May 2014, the animals were weekly monitored for hematology tests (packed cell volume) and parasitological (egg counts per gram of feces and fecal culture) in order to monitor the level of infection of sheep and they were assessed for weight, body condition score and staining ocular mucosa by FAMACHA© method. Furthermore infective larvae was recovery from pasture in times of pre-and post-grazing pasture. At 35 kg body weight, the animals were slaughtered and necropsied to collect the contents of the abomasum and small and large intestines to recover the adult parasites, carrying out the count and identification. The animals on pasture with a height of 40 cm pre-grazing obtained low nematode eggs in feces (1608 eggs / g) and 33 cm those in pre-grazing the highest average (2,539 eggs / g). The animals in different groups showed mean values of packed cell volume less than 23% (P> 0.05). Regarding to FAMACHA, the animals belonging to the groups 40 and 50 cm pre-grazing remained over 50% of individuals between FAMACHA 1 and 2 , and those to 33 and 45 cm pre-grazing showed mostly between FAMACHA 3, 4 and 5 (69.06% and 58.93%, respectively). In the culture of larvae in feces and recovery of pasture larvae before and after grazing the following genera were found, in order of prevalence: Haemonchus, Trichostrongylus, Oesophagostomum and Strongyloides. The pasture with 33 cm of pre-grazing provided the highest number of larvae recovered both in the pre and post-grazing (1,081 and 715 L3 / 100 g of green matter, respectively). Among the different groups, the sheep had an average weight of between 23 and 26 kg and variation between the body 1 and 3 scores with scores greater frequency of 1.5 to 2.It can be observed that the animals kept at different times of grazing got different answers on the parasite load. Animals kept in 40 cm pre-grazing expressed a satisfactory answer than the other groups (33, 45 and 50 cm), best supporting the action of endoparasites. Moreover, this same height, was recovered fewer infective larvae on pasture in pre and post-grazing.