Leaf Morphology Of Saplings And Adult Individuals Of Caesalpinia Echinata Lam. In A Semidecidual Forest Of Southern Bahia, Brazil [morfologia Foliar De Indivíduos Jovens E Adultos De Caesalpinia Echinata Lam. Numa Floresta Semidecídua Do Sul Da Bahia]

Caesalpinia echinata Lam. (Caesalpiniaceae) is a tree species that naturally regenerates in the forest understory and reaches the upper canopy through small gaps. We conducted a study with the objective of comparing some aspects of leaf morphology of adult individuals, in which the leaves were exposed to full sunlight, and saplings, grown in the forest understory. The study was conducted in a semidecidual forest in Jussari, southern Bahia, Brazil. Initially, eight adult and eight sapling individuals were selected and marked. In September/October, 2004 and April, 2005 eight leaves for each adult and three leaves for each sapling individual were collected and analyzed. In general, the area of leaves, rachis and leaflets, the length of rachis, the width of leaves, the number of pinnes and the dried mass of leaves were significantly higher in young individuals. Notwithstanding, the specific mass of leaves and leaflets were significantly higher in the adults. 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Consumo, digestibilidade de nutrientes e balanço de nitrogênio da silagem de capim-elefante com adição de pedúnculo de caju desidratado Intake, nutrients digestibility and nitrogen balance of elephant grass silages added different levels of dehydrated cashew stalk

A presente pesquisa foi realizada com o objetivo de avaliar o valor nutritivo de silagens de capim-elefante contendo níveis crescentes de pedúnculo de caju desidratado (PCD). Foram utilizados 20 ovinos machos e não castrados, seguindo o delineamento experimental inteiramente casualizado, com cinco tratamentos (níveis de adição de 0; 4; 8; 12 e 16%) e quatro repetições. Foram avaliados os consumos e a digestibilidades da matéria seca (MS), da matéria orgânica (MO), da proteína bruta (PB), da fibra em detergente neutro (FDN), da fibra em detergente ácido (FDA), do extrato etéreo (EE), dos carboidratos totais (CHT), dos carboidratos não fibrosos (CNF), além do valor de nutrientes digestíveis totais (NDT) e do balanço de nitrogênio (BN) das silagens. A adição de PCD não influenciou os consumos de MS, MO, FDN, FDA, CHT e NDT expresso em % PV e g kg-1 PV0,75 e as digestibilidades da MO, PB, FDN, FDA e CHT das silagens. No entanto, a adição do PCD promoveu aumento nos consumos de PB, EE e CNF (% PV e g kg-1 PV0,75), nas digestibilidades do EE e dos CNF e no valor de NDT e balanço de nitrogênio. Por outro lado, a inclusão de PCD na ensilagem do capim-elefante promoveu efeito linear decrescente na digestibilidade da FDA das silagens. Conclui-se que as silagens com adição de PCD podem ser utilizadas como volumoso para ruminantes em razão das melhorias nos consumos de PB, EE e CNF e nas digestibilidades do EE e dos CNF, além do valor de NDT e BN das silagens, recomendando-se a adição de até 16% na matéria natural.<br>The nutritive value of elephant grass silages, with increasing levels of dehydrated cashew stalk (DCS) was evaluated. Five addition levels were studied (0; 4; 8; 12 and 16%), using 20 rams in a completely randomized design with five treatments (addition levels) and four replicates (animals). Intake and digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), total carbohydrates (TC) and non-fibrous carbohydrates (NFC) were determined, as well as total digestible nutrients (TDN) and silages nitrogen balance (NB). DCS did not affect intakes of DM, OM, NDF, ADF, TC and TDN, neither digestibility of OM, CB, NDF, ADF and TC silages. Otherwise, the addition of DCS increased intakes of CP, EE and NFC and digestibility of EE, NFC, as well as TDN values and nitrogen balance. Inclusion of DCS showed linear decreasing digestibility of ADF. It is concluded that addition of DCS to silages of elephant grass up to 16% on a natural basis can be used as a forage source for ruminants