RESUMO Mais de 60% dos trabalhadores de enfermagem apresentam episódio de lombalgia durante um ano, provocando um impacto socioeconômico negativo, uma vez que é uma das maiores causas de faltas e afastamentos do trabalho. A auriculoterapia é uma técnica da acupuntura de baixo custo e não invasiva, que utiliza o pavilhão auricular como um microssistema do organismo humano mapeado por pontos que, estimulados, podem tratar diversas enfermidades. Sendo assim, o objetivo deste estudo foi verificar a eficácia da auriculoterapia com sementes de mostarda (Brassica juncea) na melhora da dor, na funcionalidade e na mobilidade lombar de profissionais técnicos e auxiliares de enfermagem do sexo feminino com dor lombar crônica. Foi realizado um ensaio clínico randomizado cego, dividido em dois grupos: um utilizou sementes de mostarda para acupressão nos pontos auriculares “Shen-Men”, “Rim”, “Simpático” e “Coluna Lombar” e o grupo placebo utilizou espuma de poliuretano de baixa densidade no lugar das sementes. Cada grupo realizou quatro sessões de auriculoterapia, uma vez por semana. Os grupos foram analisados por meio de termogramas infravermelhos e algometria por pressão para a dor, a medida dedo-chão para mobilidade e Questionário Roland-Morris para funcionalidade da coluna, com intervalo de confiança de 95%. A auriculoterapia com sementes de mostarda reduziu a temperatura média nos termogramas analisados em 0,8°C, bem como, aumentou o limiar de dor à pressão na coluna lombar das voluntárias em 0,4 Kgf, o que demonstra uma melhora significativa da dor lombar. Portanto, a auriculoterapia com sementes de mostarda mostrou-se eficaz na melhora da dor lombar.

ABSTRACT More than 60% of nursing workers have an episode of low back pain for one year, causing a negative socioeconomic impact, as this is one of the major causes of absence from work. Auriculotherapy is a low-cost, non-invasive acupuncture technique that uses the auricular pavilion as a microsystem of the human organism mapped by points that when stimulated can treat several ailments. Thus, this study aims to verify the efficacy of mustard seed (Brassica juncea) auriculotherapy in alleviating pain, improving functionality and lumbar mobility of female technical professionals and nursing assistants with chronic low back pain. A blind randomized clinical trial was conducted with two groups: one group used mustard seeds for acupressure in the ear points “Shen-Men,” “Kidney,” “Sympathetic,” and “Lumbar Spine”; the placebo group used low density polyurethane foam in place of seeds. Each group performed four auriculotherapy sessions, one per week. The groups were analyzed using infrared thermograms and pressure algometry for pain, finger-floor measurement for mobility and Roland-Morris Questionnaire for spine functionality, with a 95% confidence interval. Mustard seed auriculotherapy reduced the average temperature in the thermograms analyzed by 0.8 °C, as well as increased the pain threshold to lumbar spine pressure of the volunteers by 0.4 Kgf, which shows a significant improvement of low back pain. Therefore, mustard seed auriculotherapy was effective in alleviating low back pain.

RESUMEN Más del 60% de los trabajadores de enfermería tienen un episodio de dolor lumbar durante un año, causando un impacto socioeconómico negativo, ya que es una de las mayores causas de ausencias y despidos del trabajo. La auriculoterapia es una técnica de acupuntura de bajo costo y no invasiva que utiliza el pabellón auricular como un microsistema del organismo humano mapeado por puntos que, estimulados, pueden tratar diversas enfermedades. Así, el objetivo de este estudio fue verificar la eficacia de la auriculoterapia con semillas de mostaza (Brassica juncea) en la mejora del dolor, la funcionalidad y la movilidad lumbar de mujeres profesionales técnicas y auxiliares de enfermería con dolor lumbar crónico. Se realizó un ensayo clínico aleatorizado ciego, dividido en dos grupos: uno utilizó semillas de mostaza para acupresión en los puntos auriculares “Shen-Men”, “Riñón”, “Simpático” y “Columna Lumbar” y el grupo placebo utilizó espuma de poliuretano de baja densidad en lugar de las semillas. Cada grupo realizó cuatro sesiones de auriculoterapia una vez por semana. Los grupos se analizaron mediante termogramas infrarrojos y algometría de presión para el dolor, prueba de distancia dedos-suelo para la movilidad y Cuestionario Roland-Morris para la funcionalidad de la columna vertebral, con un intervalo de confianza del 95%. La auriculoterapia con semillas de mostaza redujo la temperatura promedio en los termogramas analizados en 0,8°C, así como aumentó el umbral de dolor a presión en la columna lumbar de las voluntarias en 0,4 Kgf, lo que demuestra una mejora significativa en el dolor lumbar. Por lo tanto, la auriculoterapia con semillas de mostaza ha demostrado ser eficaz para mejorar el dolor lumbar.

Abstract: This study aimed to evaluate nutrient intake and digestibility, performance and economic viability of steers during the rearing phase in Brachiaria brizantha cultivar Marandu graze and in feedlot. Were used fifty crossbred steers in the rearing phase, with a mean weight of 275 ± 8.18 kg, distributed in a completely randomized design with ten replications per treatments: Mineral supplementation, nitrogen supplementation, Concentrate supplementation in the order of 1 and 2 g/kg body weight and total feedlot. The total dry matter intake and body weight showed a difference (P<0.05) for animals in feedlot. Crude protein, ether extract, neutral detergent fiber corrected for ashes and protein, non-fibrous carbohydrates, total digestible nutrients showed differences for the animals that received mineral supplementation in comparison to the other managements adopted. The same performance was observed for animals in feedlot. The digestibility coefficients of dry matter, crude protein, ether extract, non-fibrous carbohydrates and total digestible nutrients showed a difference (P<0.05) for the animals that received mineral supplementation, in comparison to the other managements adopted. (P<0.05). The mean daily gain was lower (P<0.05) for animals receiving mineral supplementation. The gross margin was higher (P<0.05) for animals handled in feedlot. Considering the obtained results, it was possible to observe that the animals kept in graze with good availability of dry matter presented satisfactory performance. It is feasible to confine the animals in rearing, since it shortens the production cycle, generating favorable economic results.

Resumen Este estudio buscó evaluar la ingesta y digestibilidad de nutrientes, el rendimiento y la viabilidad económica de novillos alimentados con Brachiaria brizantha cultivar Marandú y criados bajo sistemas de pastoreo y engorda en corral. Se utilizaron 50 novillos cruzados en fase de crecimiento con un peso medio de 275 ± 8.18 kg. Los novillos se distribuyeron en un diseño completamente al azar con 10 repeticiones por tratamiento: suplementación mineral, suplementación de nitrógeno, suplementación del concentrado en el orden de 1 y 2 g/kg de peso corporal y engorda total en corral total. El consumo de materia seca total y el peso corporal fueron significativamente diferentes (P<0.05) para los animales en engorde en corral. La proteína cruda, el extracto etéreo, la fibra detergente neutra corregida para cenizas y proteína, los carbohidratos no fibrosos y los nutrientes digestibles totales fueron diferentes en los animales suplementados con minerales en comparación con los otros tratamientos. El mismo rendimiento se observó en los animales en engorde. Los coeficientes de digestibilidad de materia seca, proteína cruda, extracto etéreo, carbohidratos no fibrosos y nutrientes digestibles totales en los animales suplementados con minerales fueron significativamente diferentes (P<0.05) a los otros tratamientos. (P<0.05). La ganancia diaria promedio fue menor (P<0.05) en los animales suplementados con animales. El mayor margen bruto (P<0.05) se observó en los animales bajo engorde en corral. Los resultados obtenidos en este estudio indican que los animales en pastoreo con una buena disponibilidad de materia seca presentan un rendimiento satisfactorio. Es factible confinar a los animales en fase de cría debido a que se acorta el ciclo de producción y se obtienen resultados económicos favorables.

ABSTRACT. The aim of this study was to perform a morphological and morphoagronomic analysis of wild Manihot species from a Brazilian semiarid region for inclusion in the collection at the Center for Agricultural Sciences, Federal University of Paraíba. To characterize the 55 accessions, 12 quantitative and 18 qualitative descriptors were used. A dissimilarity matrix was generated by Mahalanobis generalized distance (D²), and clusters were identified by the UPGMA method. It was possible to verify the formation of 8 dissimilar groups based on morphological characters and 5 groups based on morphometric characters, indicating the presence of genetic diversity among accessions. The evaluated morphometric variable with the greatest relative contribution was the length between the central lobe. Based on the dissimilarity matrix, the accessions 16 x 48 were the most genetically distant accessions, followed by 47 x 49. The accessions 4 Monteiro, 16 Soledad, 38 Boa Vista, 3 Pedra Lavrada, 7 Junco, 10 Barra de Santa Rosa, 21 Monteiro, and 39 Junco are the most promising and can be used as parents in breeding programs for this forage species.

ABSTRACT Peppers belong to the Solanaceae family and present a wide genetic variability that may be accessed through phenotypic and genotypic traits. This work aimed to study the genetic divergence in an ornamental pepper F3 population by multivariate methods based on the individual and simultaneous analyses of qualitative, quantitative, and molecular data. The work was developed in the Center of Agrarian Sciences (CCA) of the Universidade Federal da Paraíba (UFPB), Paraíba state, Brazil. 44 progenies from an F3 generation were used and the characterization of 30 qualitative traits, 16 quantitative traits, and 18 pairs of microsatellite primers was performed. Individual and simultaneous analyses of the variables were performed by using the clustering method of Ward’s algorithm. Tocher’s method was used based on distance matrixes. A non-metric multidimensional scaling was applied (nMDS) for the graphic representation of the distance matrixes in the bidimensional space. Data analysis was efficient to separate the genotypes into distinct groups. There is genetic variability among the individuals of the C. annuum F3 population, verified by individual and joint trait measurements. The three clustering methods were efficient to represent the genetic distance between individuals of ornamental pepper plants. Individuals 1, 2, 7, 8, 10, 11, 21, 27, 29, 35, and 38 are indicated to advance generation and continue the breeding program.

Abstract The objective of this study was to evaluate the economic viability, through different supplementation strategies, of the post-weaning and finishing stages of cattle supplemented on Brachiaria brizantha cv. Marandu pastures during the rainy and dry seasons. The experimental period was 447 d. The study comprised the post-weaning and finishing stages of 22 intact male crossbred (½ Holstein-Zebu) cattle with an average initial weight of 164.09 ± 12.13 kg and an average age of 7 mo. The animals were distributed in a randomized design with 11 replications per treatment. The following supplementation strategies were tested: strategy 1 (S1): Mineral mix in the 1st and 3rd periods and protein-energy supplementation at 0.2 % of the body weight (BW) in the 2nd period; and strategy 2 (S2): protein-energy supplementation at 0.4 % BW in the 1st and 3rd periods, and protein-energy supplementation at 0.6 % BW in the 2nd period. Strategy 1 resulted in a lower cost per arroba produced and lower cost per hectare, generating a greater net profit per hectare and consequently a higher internal rate of return. When herbage is available, mineral supplementation supplied during the rainy season, associated with low levels of protein-energy supplementation in the dry season (S1), is of greater economic attractiveness for the development of the project, as it leads to higher internal rates of return and net present values in the entire period.

Resumen El objetivo fue evaluar la viabilidad económica, a través de diferentes estrategias de suplementación, de las etapas post destete y finalización del ganado bovino suplementado en pastoreo de Brachiaria brizantha cv. Marandú durante las temporadas de lluvias y secas. El periodo experimental fue de 447 días. El estudio comprendió las etapas post destete y finalización de 22 bovinos machos (1/2 Holstein-Cebú) enteros con un peso inicial promedio de 164.09 ± 12.13 kg y una edad promedio de 7 meses. Los animales se distribuyeron en un diseño aleatorio con 11 repeticiones por tratamiento. Se probaron las siguientes estrategias de suplementación: estrategia 1 (E1): mezcla de minerales en el 1er y 3er periodos y suplementación de proteína y energía al 0.2% del peso corporal (PC) en el 2do periodo; y estrategia 2 (E2): suplementación de proteína-energía a 0.4% PC en los períodos 1º y 3º, y suplementación de proteína-energía a 0.6% PC en el 2º período. La estrategia 1 dio como resultado un menor costo por arroba producido y un menor costo por hectárea, generando una mayor ganancia neta por hectárea y, en consecuencia, una mayor tasa interna de retorno. Cuando se dispone de forraje, la suplementación de minerales suministrada durante la temporada de lluvias, asociada con bajos niveles de suplementación de proteína y energía en la estación seca (S1), es de mayor atractivo económico para el desarrollo del sistema, ya que conduce a mayores tasas internas de valores de retorno y valores netos presentes en todo el periodo.

RESUMO O feijão-bravo (Capparis flexuosa) é uma espécie nativa da Caatinga e é utilizada como forrageira, principalmente na estação seca onde parte das espécies vegetais perdem suas folhas. Objetivou-se estudar a diversidade genética dentro e entre populações de feijão-bravo usando marcadores RAPD. O estudo foi realizado no Laboratório de Biotecnologia Vegetal do CCA/UFPB. Foram coletadas folhas de 30 acessos de feijão-bravo/população nos seguintes municípios do estado da Paraíba: Barra de Santa Rosa (BSR), Cuité (C), São João do Cariri (SJC), Damião (D), Baraúna (B) e Picuí (P). A extração de DNA seguiu a metodologia de utilização do CTAB com modificações. Análises de RAPD foram realizadas usando 18 primers e o polimorfismo de fragmentos de DNA amplificados foi visualizado em gel de agarose após eletroforese. Os dados foram submetidos ao Coeficiente de Similaridade Jaccard, agrupados seguindo a UPGMA e calculou-se o Coeficiente de Correlação Cofenética, Estresse e Distorção. 14 primers geraram polimorfismo de banda, no entanto, as populações apresentaram baixo número de locos polimórficos (27 em BSR, 18 em C, 7 em SJC, 9 em D, 0 em B e P) sendo o maior conteúdo de informação polimórfica foi encontrado nos municípios de BSR (9 grupos), C (22 grupos), São João do Cariri (7 grupos) e D (6 grupos). Formou-se 34 grupos na análise interpopulacional. As matrizes formadas apresentaram altos índices de correlação cofenética (0,95 a 0,98), baixo estresse (12,9 a 17,45%) e distorção (3,05%). Portanto, há variabilidade genética entre e dentro de populações de feijão-bravo.

ABSTRACT Brave bean (Capparis flexuosa L.) is a Caatinga species that is used as forage, mainly during the dry season when some plant species lose their leaves. The aim of this study was to assess genetic diversity within and among brave bean populations using Random Amplified Polymorphic DNA (RAPD) markers. Brave bean leaves were collected from 30 accessions in the following municipalities of Paraíba state, Brazil: Barra de Santa Rosa (BSR), Cuité (C), São João do Cariri (SJC), Damião (D), Baraúna (B), and Picuí (P). DNA extraction followed the standard methodology of CTAB with modifications. RAPD analyses were carried out using 18 primers, and polymorphism of the amplified DNA fragments was visualized using agarose gel electrophoresis. Data were used to calculate Jaccard Similarity Coefficient values, which were then used to group samples with the Unweighted Pair Group Method with Arithmetic Mean. Cophenetic Correlation Coefficient, Stress, and Distortion Coefficient values were also calculated from these analyses. Band polymorphism was generated with 14 primers, but the sampled populations showed low numbers of polymorphic loci (27 in BSR, 18 in C, 7 in SJC, 9 in D, and 0 in B and P). The highest polymorphic information content was found in samples from the BSR (9 groups), C (22 groups), SJC (7 groups), and D (6 groups) municipalities. In the interpopulation analysis, 34 groups were formed, the matrices of which showed high cophenetic correlations (0.95 to 0.98), but low stress (12.9 to 17.45%) and distortion (3.05%). Therefore, results showed that there was genetic variability both among and within brave bean populations.

Abstract Glycerin is an organic compound with an alcoholic function and can be esterified into fatty acids to form triglycerides. Due to the increasing availability of glycerin, studies that determine the best level of its inclusion in diets for ruminants are needed. This study evaluated the effects of glycerin supplementation on the proximate composition and fatty acid profile of the longissimus lumborum of heifers fed on Brachiaria brizantha pasture. Thirty-six heifers were distributed in a totally randomized design with four treatments (G0.0 = without glycerin, G4.6 = 4.6% glycerin, G9.3 = 9.3% glycerin and G14.3 = 14.3% glycerin). The addition of glycerin decreased the tetradecanoic and octadecanoic fatty acids but increased the pentadecanoic, heptadecanoic, heptadecenoic, eicosanoic, eicosatetraenoic and docosatetraenoic fatty acids. The saturated (SFA), monounsaturated (MUFA) and omega-3 (n-3) fatty acid concentrations were similar across the diets. However, the polyunsaturated (PUFA) concentrations and the PUFA:MUFA and n-6:n-3 ratios increased with the inclusion of glycerin in the diet. Glycerin levels up to 14.3% (corresponding to a substitution of 50.5% of corn for this byproduct as an energy source) did not alter the proximate composition of the meat but improved the fatty acid profile of the longissimus lumborum muscle and, consequently, increased the meat quality, potentially providing benefits for human health.

Resumen La glicerina es un compuesto orgánico con una función alcohólica que puede esterificarse en ácidos grasos para formar triglicéridos. Debido a su disponibilidad cada vez mayor, se necesitan estudios que indiquen el mejor nivel de inclusión en las dietas para los rumiantes. Este estudio evaluó los efectos de la glicerina sobre la composición próxima y el perfil de ácidos grasos de Longissimus lumborum de novillas suplementadas con pasto de Brachiaria brizantha. Se distribuyeron 36 vaquillas en un diseño totalmente aleatorizado con cuatro tratamientos (G0.0 = sin glicerina, G4.6 = 4,6% de glicerina, G9.3 = 9.3% de glicerina y G14.3 = 14.3% de glicerina). La adición de glicerina disminuyó los ácidos grasos tetradecanoico y octadecanoico, pero aumentó los ácidos grasos pentadecanoico, heptadecanoico, heptadecenoico, eicosanoico, eicosatetraenoico y docosatetraenoico. Las concentraciones de ácidos grasos saturados (SFA), monoinsaturados (MUFA) y omega-3 (n-3) fueron similares en todas las dietas. Sin embargo, las concentraciones de poliinsaturados (PUFA) y los niveles de PUFA: MUFA y n-6: n-3 aumentaron con la inclusión de glicerina en las dietas. Los niveles de glicerina hasta 14.3% (que corresponden a una sustitución del 50.5% de maíz por este subproducto como fuente de energía) no alteraron la composición proximal de la carne pero mejoraron el perfil de ácidos grasos del músculo Longissimus lumborum y, en consecuencia, aumentaron la carne calidad, potencialmente proporcionando beneficios para la salud humana.

Objetivou-se com este estudo avaliar o perfil fermentativo, perdas e a composição bromatológica de silagens de cinco cultivares de sorgo. Foi utilizado um delineamento experimental inteiramente casualizado com cinco repetições. Os tratamentos experimentais foram representados por cinco cultivares de sorgo (Sorghum bicolor (L). Moench): 'BRS Ponta Negra', 'BRS 610', 'BRS 655', 'BRS 800' e 'BRS 810'. Houve variação (P<0,05) para o pH nos genótipos estudados, com maior resultado para o genótipo 'BRS 610'. Os valores médios de ácido lático, ácido acético e ácido propiônico, diferiram entre as cultivares (P<0,05), variando de 32,9 a 59,5; 19,8 a 39,8; e 0,0 a 1.3g kg-1, respectivamente. A recuperação de matéria seca variou entre as cultivares (P<0,05), em que as silagens dos cultivares 'BRS Ponta Negra' e 'BRS 810', é que tiveram menor recuperação de matéria seca, com valores de 757,1 e 776,1g kg-1, respectivamente. Houve diferença (P<0,05) para teores de matéria seca, proteína bruta, extrato etéreo, fibra em detergente neutro, carboidratos não-fibrosos e carboidratos totais entre as cultivares. Conclui-se que, apesar das diferenças morfológicas e químicas entre as cultivares, as silagens resultantes tinham adequado padrão de fermentação.

This study aimed to assess the fermentation profile, losses and chemical composition of the silages of five sorghum cultivars. A completely randomized design with five replicates was used. The experimental treatments were represented by five sorghum cultivars (Sorghum bicolor (L). Moench): 'BRS Ponta Negra' , 'BRS 610', 'BRS 655', 'BRS 800' and 'BRS 810'. There was variation (P<0.05) for the pH in the cultivars studied, with highest result of pH by 'BRS 610'. The average percentages of lactic acid, acetic acid and propionic acid, differed (P<0.05) among the cultivars, ranging from 32.9 to 59.5, 19.8 to 39.8, and 0.0 to 1.3g kg-1, respectively. The dry matter recovery varied among cultivars (P<0.05), allowing the identification of BRS Ponta Negra, and 'BRS 810' silages, as those which recovered the lowest dry matter, with values of 757.1 and 776.1g kg-1, respectively. There were differences (P<0.05) for dry matter, crude protein, ether extract, neutral detergent fiber, non-fibrous carbohydrates and total carbohydrates contents among the cultivars. It was concluded that, despite the morphological and chemical differences among cultivars, the resulting silages had good fermentation profile.

Objetivou-se quantificar a população de mofos e leveduras, avaliar as perdas de matéria seca e a composição bromatológica de fenos de capim-buffel amonizados com ureia. Utilizou-se um delineamento inteiramente casualizado, com cinco tratamentos e cinco repetições. Os tratamentos compreenderam aos níveis de ureia (0; 0,5; 1,0; 2,0; 4,0%), que foram adicionados aos fardos de feno com base na matéria seca. A inclusão de 1,0% de ureia elevou a recuperação de matéria seca (93,21%) em relação ao feno não amonizado. Observou-se efeito quadrático para o pH, com o maior valor observado no nível de 0,5% de ureia (8,88), reduzindo nos demais níveis de ureia. A adição de níveis de ureia foi eficiente em reduzir a população de mofos e leveduras, reduzindo de 6,50 log UFC/g no feno sem tratamento com ureia para 3,65 log UFC/g quando adicionados 4% de ureia no feno. A adição de ureia proporcionou aumento nos teores de matéria orgânica e proteína bruta dos fenos de capim-buffel, atingindo os maiores valores com a utilização de 4,0% de ureia, com 90,96% e 14,03% para matéria orgânica e proteína bruta, respectivamente. A aplicação de ureia não proporciona diminuição em relação às perdas de matéria seca, exceto na dose de 1,0%, no entanto, é eficiente em reduzir a população de mofos e leveduras e elevar os teores de proteína bruta de fenos de capim-buffel.

The objective of this study was to quantify the population of molds and yeasts, evaluate losses dry matter and chemical composition of buffelgrass hay ammoniated with urea. We used a completely randomized design with five treatments and five replicates. The treatments consisted the urea levels (0, 0.5, 1.0, 2.0, and 4.0%) that were added to the hay bales based on dry matter. The inclusion of 1.0% of urea increased dry matter recovery (93.21%) compared to non-ammoniated hay. There was quadratic effect for the pH with highest value observed at the level of 0.5% of urea (8.88), reducing the other levels of urea. The addition of urea levels was efficient to reduce the population of molds and yeasts, reducing from 6.50 log CFU/g in untreated hay with urea to 3.65 log CFU/g when added 4% of urea in the hay. The addition of urea resulted in increased contents of organic matter and crude protein hay buffelgrass, reaching the highest values with the use de 4.0% of urea, with 90.96% and 14.03%, respectively. The application of urea does not provide decreased in respect losses of dry matter, except at a level of 1.0%, however it is efficient in to reduce the population of molds and yeasts and elevate the crude protein of buffel grass hay.

The present study evaluated the microbial population, fermentation profile, losses and dry matter recovery, and chemical composition of silages of buffel grass at different cutting heights. To evaluate the microbial fermentation dynamics, the treatments resulted from a 4 × 5 factorial combination consisting of 4 cutting heights and 5 fermentation periods, in a completely randomized design with three replications. The fermentation was evaluated at the end of 1, 3, 7, 15 and 30 days. The other characteristics of silages with 30 days were evaluated following a completely randomized design with four treatments, consisting of 4 cutting heights (30, 40, 50 and 60 cm), and five replications. Fermentation period and cutting height effects and interaction between both factors were observed on the populations of lactic acid bacteria (LAB), enterobacteria and molds and yeasts. The peak of development of LAB populations was observed on the seventh day of fermentation for the heights of 40 and 50 cm, with 8.25 and 8.30 log cfu/g, respectively. The pH values of silages ranged with different cutting heights, in which at the height of 50 cm the decrease was most pronounced. However, the pH values were similar between the cutting heights at the end of 30 days of fermentation. Quadratic relationship was observed between lactic acid concentrations and cutting heights. The crude protein content behaved linearly, initially showing 128.5 g/kg DM at 30 cm, decreasing as the cutting heights increased. The neutral detergent fiber and ether extract contents increased linearly with the cutting heights. Based on microbial populations, fermentation, losses and chemical composition, it is recommended to harvest buffel grass for silage from 50 cm on.

O aumento da intensidade do uso do solo e a diminuição da cobertura vegetal nativa no nordeste brasileiro têm levado à degradação dos recursos naturais e, em especial, à diminuição da fertilidade do solo. Diante disso, o presente trabalho objetivou avaliar as mudanças nos atributos físicos e químicos do solo em área de floresta nativa secundária e pastagem na microrregião do Brejo Paraibano. Foram selecionadas três áreas, na propriedade Engenho Mineiro, cujo solo local foi classificado como Argissolo Vermelho Amarelo, sendo duas representadas por pastagens de capim Brachiaria ssp, exploradas por mais de 25 anos e com claros sinais de degradação, e a outra em área de floresta nativa secundária. O delineamento utilizado foi o inteiramente casualizado no esquema de parcelas subdivididas com cinco repetições. As amostras de solo foram coletadas de 0-10, 10-20 e 20-30cm de profundidade. Em virtude do desnível da área, procedeu-se às coletas numa linha em curva de nível, distanciadas 10m entre si. Os atributos físicos avaliados foram: densidade do solo e de partículas, porosidade total, argila total e natural, grau de floculação, diâmetro médio ponderado de agregado seco e úmido e determinação da distribuição de macro e micro agregados, separados por via seca e via úmida. Para os atributos químicos, foram determinados os valores de pH em água e os teores de cálcio, magnésio, fósforo, potássio, alumínio trocável, hidrogênio + alumínio e de matéria orgânica (MO), para as áreas e profundidades estudadas. O solo das áreas estudadas, em geral, apresentou baixa fertilidade. Dos resultados, verificou-se que mudanças na cobertura original acarretaram aumento no pH e redução no teor de matéria orgânica. A área cultivada com pastagem apresentou aumento dos valores de densidade do solo, densidade de partículas e diminuição da porosidade total, a mudança da cobertura vegetal influenciou nos valores de macro e micro agregados nos ambientes estudados. A utilização da segmentação da topossequência por posições no relevo, uso e profundidades, visando à determinação da degradação do solo, mostrou-se eficiente na avaliação das diferentes profundidades deste. O sistema de manejo utilizado ocasiona mudanças nos atributos físicos e químicos do solo, que contribuem para o processo de degradação da área.

The increased intensity of land use and declining native vegetation in northeastern Brazil have led to degradation of natural resources and in particular to the decline of soil fertility.The present study aimed to assess changes in soil physical and chemical properties in secondary areas of native forest and pasture in the microregion of swamp Paraiban. Three areas were selected in the Engenho Mineiro property, whose land area was classified as Alfissol, and represented by pasture grass Brachiaria ssp which is being explorated for over 25 years with clear signs of degeneration and the other by a area of secondary native forest. The design was completely randomized in a split-plot with five replications. Soil samples were collected from 0-10, 10-20 and 20-30cm. Due to the unevenness of the area proceeded collect in line in curve level, 10.0m apart from each other. The physical attributes evaluated were: bulk density and particle, total porosity, degree of flocculation, and totality native clay, degree of flocculation, aggregate dry and wet mean weight diameter and determination of the distribution of macro and micro aggregates separated by dry and wet. For the chemical attributes were determined pH values in water and calcium, magnesium, phosphorus, potassium, aluminum, hydrogen + aluminum, and organic matter (OM) for the areas and depths studied. The soils of, in general, showed low fertility. From the results, it was found that changes in the the original coverage cause an increase in pH and reduction in organic matter content. The area cultivated with pasture presented higher values of soil density, density of particles and reduction of total porosity. The change in the vegetation cover influenced the values of macro and micro aggregates in the studied environments. The use of segmentation by the toposequence positions in the landascape, use and depths, to the determine soil degradation, was efficient in evaluating the different depths of it. The management system used causes changes in the soil physical and chemical attributes that contribute to the process of soil degradation.