The forage sward height measurement is a practical and potential tool for grazing management. Thus, the objective of this study was to evaluate the structure of pasture and forage accumulation related to sward pre-grazing height of Panicum maximum cv. Massai, before being grazed by sheep. The study was conducted in the Federal University of Rio Grande do Norte, Macaíba, Brazil. The treatments were the pre-grazing sward heights at: 35, 40, 45 and 50 cm. The post-grazing height was 15 cm for all treatments. The interaction between the pre-grazing sward heights and grazing cycles was only statistically significant for light interception (LI) and leaf area index (LAI). The LI had linear and positive effect to the pre-grazing heights in only one of three grazing cycles, with approximately 1% increase in LI for each centimeter grown in the sward. The total forage mass had linear regression, every centimeter increased in height, there was a correspondent dry matter (DM) increase of 187 kg ha -1 in forage mass. There was a linear response between leaf blade mass and dead material with sward height. The post-grazing lowest LI was 29.42% at 42.05 cm high. The lowest amount of LI was 29.42% at 42.05 cm high. The minimum LAI was 0.69. The top DM and mineral matter (MM) accumulation rate were linear and had 58.32 and 20.46 kg ha -1 day -1 MS, respectively. Massai guineagrass grazed by sheep must be handled between 35 and 40 cm high at pre-grazing when associated with post-grazing height of 15 cm.

This study aimed to evaluate the agronomic and structural characteristics of massai grass under grazing by sheep supplemented in the dry season. The treatments were supplements offered to sheep in massai grass pastures: multiple mixture, leucaena hay, gliricidia hay and soybean meal. The pastures were evaluated regarding: canopy height; forage accumulation and mass; accumulation, mass and percentage of morphological constituents; leaf:stem and green mass:dead material ratio; and pre‐ and post‐grazing forage bulk density. Higher pre‐grazing heights were observed (27.4 cm) in pasture occupied by animals supplemented with multiple mixture. No effects of supplement types for forage mass (average of 4426.6 kg ha−1 of dry matter) or of morphological constituents in pre‐grazing were observed; however, a grazing cycle effect was observed for these variables, with decreased forage mass in the order of 20% between the first and fourth pasture cycle. Involvement of dead material in forage mass increased by 45 and 23% in the pre and post‐grazing, respectively, from the first to the third grazing cycle. Using protein supplements in sheep's diet was not able to modify massai grass structure in the dry season. Massai grass is alternative forage for supplemented sheep production systems in pastures during the dry season, supporting grazing in 150 mm rainfall conditions for 6 months.

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Due to the multifactorial aspect between the morphogenetic, morphological and agronomic characteristics of the forage plants, it is necessary to look for management options that increase the production and the utilization of the mass of forage submitted to different frequencies of defoliation and nitrogen levels. The objective of this study was to verify the effects of two defoliation frequencies and two levels of nitrogen applied in a single dose on the morphogenetic, structural and forage production of piatan grass in the water period. The work was carried out in the agrostological field of the Faculty of Veterinary Medicine and Animal Science (UFMS), Campo Grande -MS. The experimental area was composed of 12 plots of 18 m² each of Brachiaria brizantha cv. Piatã (Syn. Urochloa brizantha cv. Piatã). The experimental design was completely randomized and the treatments consisted of two defoliation frequencies (with cut intervals of 28 and 35 days) and single application of two levels of nitrogen (100 and 200 kg ha -1 of N, in the form of urea) . Therefore, piatan grass pastures can be managed with a single fertilization of 100 kg ha -1 of N, with height close to 30 cm, as the production of leaf blades is not compromised. The single application of high doses of N does not increase the number, but raises the individual weights of existing tillers without affecting the morphogenic and morphological characteristics of the forage canopy. For pastures of piatã grass established in soils of good fertility it is recommended as a management strategy to use 20 cm as minimum height of cut or grazing and frequency of with interval of 28 days and height of approximately 30 cm. In established pastures, in the water period, if it is desired to reduce the dose fractionation of N, it is recommended as a single application the dose of up to 100 kg of N ha -1 immediately after the first cut.

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The objective of this study was to analyze colostrum and milk compositions of ewes kept in pasture receiving different types/levels of supplementation and to analyze milk composition variation throughout the initial third lactation period. After confirmation of pregnancy, 54 ewes were kept in pasture and supplemented from the final third of gestation until weaning with multiple mixture or concentrate (0.4% or 0.8% of body weight). Milk collections were carried out in the postpartum period to collect colostrum (day 0), and on the seventh, 14th, 21st and 28th milking days. Samples were obtained by manual milking and analyzed for protein, fat, casein, lactose, total solids and defatted dry extract. No effects from the different types of supplementation were observed on the colostrum composition or in relation to milk composition. An effect of supplementation was only found for lactose contents, which were higher for animals that consumed a higher level of supplementation. In relation to the milking days, a linear decrease in protein, casein, total solids and defatted dry extract contents was observed between the seventh and the 28th day of lactation. No interaction between type of supplementation and the milking days was observed. The different types of supplementation did not alter the colostrum composition of Santa Inês crossbred ewes, however they had an influence on milk composition. Protein, casein, total solids and defatted dry extract decrease linearly between the seventh and the 28th day of lactation.

No abstract

Intensificar a criação de ovinos para a produção de carne no Brasil, necessita do controle dos efeitos ambientais e genéticos, que afetam o desenvolvimento dos animais e dependem da correta utilização dos manejos nutricionais, reprodutivos e sanitários. O peso ao nascer determina a sobrevivência das crias e seus desempenhos subsequentes. Esse índice pode ser influenciado por fatores diretamente relacionados ao animal, como raça, idade, sexo da cria e tamanho dos pais, e por outros fatores como nutrição, sanidade e número de crias por parto. O ganho de peso médio diário, índice de importância para avaliação do desempenho animal, permite acompanhar o desempenho ponderal das crias, principalmente nos sistemas para produção de carne. Diante do exposto, objetivou-se avaliar a influência do uso de suplementos em pasto diferido para matrizes e do tipo de parto sobre o desempenho dos cordeiros. Fundamentação Teórica A nutrição inadequada da ovelha, particularmente no estágio final da gestação, pode comprometer o desenvolvimento de alguns órgãos do feto que altera a fisiologia do animal e resulta em modificações no crescimento pré e pós-natal do cordeiro (GERASEEV et al., 2006).