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

Caracterização da caprinocultura nas microrregiões da chapada do Apodi e de Angicos do Estado do Rio Grande do Norte

The objectives of this study were to characterize the goat production systems and to identify the factors limiting the production chain and develop solutions to improve the goat industry in the Rio Grande do Norte State, Brazil. One hundred and sixty two questionnaires were applied to goat farmers looking for productive, economic and social information about the utilized systems in the micro regions of Chapada do Apodi and Angicos. The majority producers interviewed were male, aging from 31 to 50 years old, attended elementary school, associated to farm organizations and living with his family on farm. Their main concerns are feeding the heard and animal theft. Their average farmlands areas range from 11 to 50 hectares. Goat meat is the main production in Chapada do Apodi whereas milk is produced by farmers in Angicos micro region. The majority of goat production works with an extensive system, with low technological inputs. It was detected that the meat and milk production as the marketing of goat products is not well conducted. Other point to be improved is to increase the meat and dairy goat products to be available for consumers. Goat systems for meat and milk production has great to potential for this micro regions, although public policies for an organized supply chain is needed

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

Estimação de parâmetros genéticos para resistência à infecção por IMNV em camarões Litopenaeus vannamei por meio de análise de sobrevivência

The main specie of marine shrimp raised at Brazil and in the world is Litopenaeus vannamei, which had arrived in Brazil in the `80s. However, the entry of infectious myonecrosis virus (IMNV), causing the infectious myonecrosis disease in marine shrimps, brought economic losses to the national shrimp farming, with up to 70% of mortality in the shrimp production. In this way, the objective was to evaluate the survival of shrimps Litopenaeus vannamei infected with IMNV using the non parametric estimator of Kaplan-Meier and a model of frailty for grouped data. It were conducted three tests of viral challenges lasting 20 days each, at different periods of the year, keeping the parameters of pH, temperature, oxygen and ammonia monitored daily. It was evaluated 60 full-sib families of L. vannamei infected by IMNV in each viral challenge. The confirmation of the infection by IMNV was performed using the technique of PCR in real time through Sybr Green dye. Using the Kaplan-Meier estimator it was possible to detect significant differences (p <0.0001) between the survival curves of families and tanks and also in the joint analysis between viral challenges. It were estimated in each challenge, genetic parameters such as genetic value of family, it`s respective rate risk (frailty), and heritability in the logarithmic scale through the frailty model for grouped data. The heritability estimates were respectively 0.59; 0.36; and 0.59 in the viral challenges 1; 2; and 3, and it was also possible to identify families that have lower and higher rates of risk for the disease. These results can be used for selecting families more resistant to the IMNV infection and to include characteristic of disease resistance in L. vannamei into the genetic improvement programs

Valor nutritivo de fenos de moringa (moringa oleifera lam) com diferentes idades de corte

This study was conducted to evaluate the consumption and digestibility of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), total carbohydrates (TC), non-fiber carbohydrates (NFC) and neutral detergent fiber (NDF) in sheep fed hay moringa (Moringa oleifera Lam) obtained with four cutting ages (28, 35, 42 and 49 days). We used 20 females Morada Nova breed, with 20kg of live weight, distributed in a completely randomized design and maintained in metabolism cages. There was a negative linear effect of age of cutting on DM intake, with an estimated maximum consumption of 0.67 kg / day for the hay produced at 28 days of cutting. It was also observed linear behavior, with an estimated maximum consumption 172g/dia, 0.36 kg / day; 18g/dia, at 35, 42 and 49 days old, for CP, OM and EE, respectively. For NDF, quadratic effect was found with advancing maturity of the plant. The apparent digestibility of DM, CP, OM and TC linearly decreased with advancing age of cutting hay Moringa oleifera. It was concluded that the hay Moringa oleifera showed better nutritional value after 28 days of cutting

Utilização de bagaço de caju desidratado e complexo enzimático na ração para codornas japonesas em postura

Given the significant share of food costs of poultry production, it is necessary to use strategies and techniques to maximize the utilization and biological value of the components of the diets, keeping constant or improving animal performance. In this context, seeking partial substitution of corn and the best use of the constituents of the diet, the present study aimed to evaluate the effects of inclusion of cashew pomace dehydrated (BCD) and enzyme complex (EC) in the diet on performance and quality eggs of Japanese quails. A total of 200 Japanese quail at 87 days of age, in 25 cages in a completely randomized design in a factorial 2 x 2 + 1 (two levels of cashew bagasse x two levels of enzymes) + control diet without cashew bagasse totaling five treatments with five replicates of eight birds each repetition. The experiment lasted 84 days, divided into four periods of 21 days. The treatments consisted of T1-Ration Control, T2-ration with 7.5% without EC BCD, T3-ration with 7.5% BCD with CE, T4-Ration with 15% BCD without EC and T5-Feed with 15% of BCD with EC. The enzyme complex (EC) is used fermentation product of Aspergillus niger, and cashew bagasse was obtained from the juice industry, passed through drying and crushing process for producing the bran. The performance and egg quality of quails, and performance variables: feed intake (FI), feed conversion ratio per dozen eggs (CAKDZ) and egg mass (CAMO), egg production (OP% bird / day), average egg weight (PMO) and egg mass (MO), and variables were egg quality, specific gravity (SG), Haugh unit (HU), yolk index, and the relationships between components eggs (%albumen,% yolk and %shell). Data were analyzed with the Statistical SAEG (2007). The 7.5 and 15% of cashew bagasse, independent of the enzyme complex decreased feed intake and improved the average egg weight. The two levels with the addition of EC showed significant differences for feed conversion by egg mass. The 7.5 with the addition of enzyme complex obtained the lowest average feed conversion per dozen eggs. The inclusion of up to 15% of cashew bagasse dehydrated with or without addition of enzyme complex in the diet of Japanese quails not interfere in the internal and external quality of eggs. The 7.5 and 15% BCD without added enzyme complex gave better means for specific gravity. Under conditions in which the experiment was conducted, it can be stated that the inclusion of up to 15% of cashew bagasse dehydrated with added enzyme complex feeding quail is economically viable, with the level of 7.5% with the addition of complex enzyme presented the best economic indices

Caracterização do sistema agropecuário dentro da agricultura familiar como subsídio de políticas públicas

The objective of this study was to characterize the socioeconomic profile of the family farmers who live and work in Brazilian rural space and highlight the importance of family agribusiness through the significant relation between some variables as the value of the total production, GDP share in total area of the establishments, agricultural production and farmer income, that show the important participation of these farmers in agricultural productivity and consequently on the economy of country. Therefore, this sector deserves a greater attention and more investment in the development of public policies that lead to a quality education in rural areas, availability of technical courses for farmers, technical assistance more efficient and effective, as well as funding more readily available

Avaliação genética da eficiência reprodutiva em vacas pardo-suíças por meio da análise de sobrevivência

Among the traits of economic importance to dairy cattle livestock those related to sexual precocity and longevity of the herd are essential to the success of the activity, because the stayability time of a cow in a herd is determined by their productive and reproductive lives. In Brazil, there are few studies about the reproductive efficiency of Swiss-Brown cows and no study was found using the methodology of survival analysis applied to this breed. Thus, in the first chapter of this study, the age at first calving from Swiss-Brown heifers was analyzed as the time until the event by the nonparametric method of Kaplan-Meier and the gamma shared frailty model, under the survival analysis methodology. Survival and hazard rate curves associated with this event were estimated and identified the influence of covariates on such time. The mean and median times at the first calving were 987.77 and 1,003 days, respectively, and significant covariates by the Log-Rank test, through Kaplan-Meier analysis, were birth season, calving year, sire (cow s father) and calving season. In the analysis by frailty model, the breeding values and the frailties of the sires (fathers) for the calving were predicted modeling the risk function of each cow as a function of the birth season as fixed covariate and sire as random covariate. The frailty followed the gamma distribution. Sires with high and positive breeding values possess high frailties, what means shorter survival time of their daughters to the event, i.e., reduction in the age at first calving of them. The second chapter aimed to evaluate the longevity of dairy cows using the nonparametric Kaplan-Meier and the Cox and Weibull proportional hazards models. It were simulated 10,000 records of the longevity trait from Brown-Swiss cows involving their respective times until the occurrence of five consecutive calvings (event), considered here as typical of a long-lived cow. The covariates considered in the database were age at first calving, herd and sire (cow s father). All covariates had influence on the longevity of cows by Log-Rank and Wilcoxon tests. The mean and median times to the occurrence of the event were 2,436.285 and 2,437 days, respectively. Sires that have higher breeding values also have a greater risk of that their daughters reach the five consecutive calvings until 84 months

Estrutura do dossel e acúmulo de forragem dos capins piatã e marandu sob pastejo com ovinos

The objective of this scientific work was to evaluate the tillering and mass production of Brachiaria brizantha Piatã and Marandu grasses with two statures of post-grazing. The experimental lineation was in factorial arrangement (2 pastures x 2 residue stature) with subplots (grazing cycle). The experimental period was from March to October of 2012. The target stature on pre-grazing was 50 cm and on post-grazing 15 and 25 for each cultivar. The following variables were analyzed: tiller population density, forage mass, morphological components, accumulation and accumulation rate. Three grazing cycles were obtained. Marandu grass presented larger forage mass on pre-grazing and lower stem production than piatã grass. No difference was observed between the two cultivars regarding the leaf blade production. There was no difference on forage mass, leaf blade, stem, and dead material production between the two statures of post-grazing. The pastures managed at 25 cm presented accumulation rate compared to those with 15 cm. Concerning the accumulation rate on the two cultivars, piatã and marandu grasses, Marandu grass presented higher amount than the piatã grass, and also presented higher values on the rate of basal tiller appearing on 15 cm stature post-pasture feature. Piatã grass managed at 25 cm developed smaller tiller amount on the second generation and greater tiller amount on the third generation than marandu grass. The greater tiller population density was observed on 25cm post-grazing pastures. There was no statistical difference of density between the two cultivars and between the cycles. Accordingly, it is concluded that piatã and marandu cultivars can be managed with 15cm and 25 cm post-grazing statures

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

Análises técnica e econômica da cultura da bananeira 'Maçã' (Musa spp.) na região noroeste do Estado de São Paulo

Este trabalho foi realizado no Escritório de Desenvolvimento Rural - Jales, região noroeste do Estado de São Paulo, com o objetivo de efetuar um levantamento do potencial da cultura da banana 'Maçã' na região, determinando-se indicadores técnicos e econômicos de dois sistemas de produção, os quais utilizam, no plantio, mudas micropropagadas e convencional. O levantamento de dados necessários à realização da pesquisa nos aspectos ligados à elaboração das matrizes de coeficientes técnicos, base para estimativas de custos de produção, foi obtido diretamente junto a produtores da região, e a metodologia de custos foi baseada no custo total de produção. Os resultados econômicos mostraram-se satisfatórios na região para os dois sistemas de produção, mas a receita líquida obtida com a utilização de mudas micropropagadas foi 34% maior que a obtida no sistema convencional.

Plantas de cobertura, sucessão de culturas e manejo do solo em feijoeiro

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

Avaliação do ciclo de vida no Brasil: uma investigação nas principais bases científicas nacionais

A avaliação do ciclo de vida (ACV) é uma metodologia de avaliação de impacto ambiental de produtos e sistemas de produção considerando todo o ciclo de vida, desde a aquisição de matérias-primas até a disposição final. Este trabalho consistiu na investigação do progresso dos estudos sobre ACV no Brasil, por meio de uma pesquisa bibliográfica em eventos e periódicos oficiais ou reconhecidos pela Associação Brasileira de Engenharia de Produção e na base de dados SciELO Brasil. Foram identificados 80 artigos, a maioria de instituições das regiões Sul e Sudeste. A Universidade de São Paulo (USP) e Universidade Federal de Santa Catarina (UFSC) apresentaram o maior número de publicações dentre as 50 instituições identificadas. Verificou-se que 17 artigos aplicaram efetivamente a metodologia ACV em um estudo de caso, sendo que 11 utilizaram a metodologia para avaliar processo produtivo e 6 para comparar materiais ou processos

Composição físico-química e potencial para ensilagem do sorgo-de-guiné gigante em seis épocas de semeadura

A ausência de culturas alternativas para o cultivo de outono-inverno é um entrave nos sistemas de produção agrícola, principalmente em regiões de inverno seco. O objetivo deste trabalho foi avaliar a produção de forragem, o potencial para ensilagem e a composição química do sorgo-de-guiné gigante (Sorghum bicolor subsp. bicolor raça guinea), de acordo com a época de semeadura. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições e seis épocas de semeadura. Verificou-se antecipação dos estádios de desenvolvimento da planta, à medida que houve atraso na semeadura, em virtude de a espécie apresentar sensibilidade ao fotoperíodo. Semeaduras tardias, apesar de menor produtividade, proporcionaram forragem com características químico-bromatológicas melhores. Diante da boa produção de matéria seca e seu potencial para ensilagem, esse genótipo é uma boa opção a ser utilizada.

Avanços metodológicos na avaliação de alimentos e de exigências nutricionais para aves e suínos

A produção industrial de aves e suínos mostrou enormes avanços nos últimos anos, principalmente devido ao aumento dos conhecimentos na área de genética e de nutrição. Na área de avaliação dos alimentos e das exigências nutricionais de animais monogástricos, as melhoras se dão a passos largos, devido á seriedade com que os profissionais encaram a responsabilidade de fazer pesquisa de qualidade dentro e fora do país. Neste trabalho serão abordadas as metodologias que permitem melhorar a utilização dos alimentos de maneira mais eficiente e econômica. Serão citados alguns cuidados e procedimentos essenciais para executar adequadamente experimentos de desempenho com aves e suínos. Na atualidade, para a realização de experimentos com monogástricos, é necessário: definir claramente os objetivos, utilizar animais com peso inicial uniforme, usar número adequado de repetições e de animais por unidade experimental. Testes de médias devem ser usados para as variáveis qualitativas e quando a variável independente for quantitativa aplicar análise de regressão. O nível de significância utilizado (5, 7, 10%) pode variar conforme a importância econômica da característica estudada. A adequada condução dos ensaios, sejam de crescimento ou de digestibilidade, é fundamental para que as ferramentas apresentadas possam ter efetividade, resultando na melhora da produtividade e na redução dos custos e da excreção de nutrientes.