4 research outputs found
Seletividade aparente de bovinos em pastos de capim-braquiária sob perÃodos de diferimento
Seletividade aparente de bovinos em pastos de capim-braquiária sob perÃodos de diferimento
RESUMO Objetivou-se compreender o efeito do perÃodo de diferimento sobre a seletividade aparente de bovinos pelos componentes morfológicos e de valor nutritivo do pasto de Brachiaria decumbens cv. Basilisk. Adotaram-se o esquema de parcela subdividida e o delineamento em blocos ao acaso com duas repetições. Foram estudados quatro perÃodos de diferimento (73, 103, 131 e 163 dias) e duas amostras de forragem (disponÃvel na pastagem (DP) e obtida pela simulação de pastejo (SP)). As percentagens de lâmina foliar viva (LFV), matéria seca potencialmente digestÃvel (MSPD) e proteÃna bruta (PB) foram maiores na amostra de SP, quando esta foi comparada à forragem DP. Padrão de resposta contrário ocorreu com os percentuais de colmo vivo (CV), colmo morto (CM) e fibra em detergente neutro (FDN). De modo geral, o maior perÃodo de diferimento resultou em pior composição morfológica e valor nutritivo das forragens. Os Ãndices de seletividade aparente (ISA) da LFV, do CV e da lâmina foliar morta (LFM) aumentaram linearmente com o perÃodo de diferimento. O ISA do CM apresentou maiores valores em pastos sob perÃodos intermediários de diferimento. Com o aumento do perÃodo de diferimento, os ISA da FDN e da MSPD permaneceram constantes, os ISP da FDN potencialmente digestÃvel e da PB reduziram linearmente, e o ISP da FDN indigestÃvel incrementou de maneira linear. O ISA permite a compreensão da seletividade dos componentes morfológicos e das entidades nutricionais do pasto pelos bovinos. A redução do perÃodo de diferimento melhora a estrutura do pasto e otimiza a seletividade dos bovinos
Sheep production during the rainy season in marandu palisadegrass swards previously utilized under deferred grazing
ABSTRACT The objective of this study was to evaluate the effects of Brachiaria brizantha cv. Marandu syn. Urochloa brizantha cv. Marandu (Marandu palisadegrass) in late winter on pasture structure, apparent selectivity, and sheep production during spring and early summer. The conditions of deferred pastures at the end of winter were: low (15.1cm and 4600kg/ha of DM), medium (23.2cm and 5940kg/ha of DM), high (31.4cm and 7640kg/ha of DM) and high/mowed (31.3cm and 7200kg/ha of DM, mowed to 8cm). The experiment was conducted in split plot design (sward conditions at the end of winter: low, medium, tall and tall/lowered) during time (early, middle and late spring/summer) and completely randomized design with three replications. The percentages of live leaf laminae in available forage and in simulated grazing samples were higher in tall/lowered sward and lower in high sward, oppositely to percentage of dead tissue. Only at the beginning of the grazing period the high/lowered sward had lower forage mass and bulk density. This remained high in high sward during all the grazing period. The sheep performance and the animal production per area were higher in low sward and lower in tall swards. The low sward has better structure and higher sheep production starting at spring. The lower of the marandu palisade grass at late winter improves this structure and increases sheep production during spring and early summer
Sheep production during the rainy season in marandu palisadegrass swards previously utilized under deferred grazing
<div><p>ABSTRACT The objective of this study was to evaluate the effects of Brachiaria brizantha cv. Marandu syn. Urochloa brizantha cv. Marandu (Marandu palisadegrass) in late winter on pasture structure, apparent selectivity, and sheep production during spring and early summer. The conditions of deferred pastures at the end of winter were: low (15.1cm and 4600kg/ha of DM), medium (23.2cm and 5940kg/ha of DM), high (31.4cm and 7640kg/ha of DM) and high/mowed (31.3cm and 7200kg/ha of DM, mowed to 8cm). The experiment was conducted in split plot design (sward conditions at the end of winter: low, medium, tall and tall/lowered) during time (early, middle and late spring/summer) and completely randomized design with three replications. The percentages of live leaf laminae in available forage and in simulated grazing samples were higher in tall/lowered sward and lower in high sward, oppositely to percentage of dead tissue. Only at the beginning of the grazing period the high/lowered sward had lower forage mass and bulk density. This remained high in high sward during all the grazing period. The sheep performance and the animal production per area were higher in low sward and lower in tall swards. The low sward has better structure and higher sheep production starting at spring. The lower of the marandu palisade grass at late winter improves this structure and increases sheep production during spring and early summer.</p></div