Crescimento e produção do capim massai sob déficit hídrico / Growth and production of grass massai under water deficit

Objetivou-se avaliar os efeitos de diferentes turnos de rega sobre as características de crescimento e produção do capim massai. A pesquisa foi realizada em casa de vegetação da Universidade Federal do Ceará-UFC, Campus do Pici, Fortaleza, CE. Utilizou-se delineamento em blocos casualizados, com cinco tratamentos constituídos dos intervalos de irrigação de 2, 4, 6, 8 e 10 dias, com quatro repetições. Foram avaliados: o número de folhas vivas por perfilho (NFV), taxa de alongamento de folhas (TAlF), taxa de alongamento de colmo (TAlH), taxa de aparecimento de folhas (TApF), taxa de senescência foliar (TSF), filocrono, altura, índice de área foliar (IAF), razão folha/colmo (F/C), número de perfilhos vivos (NPV), relação matéria viva/matéria morta (MV/MM), matéria seca (MS), produção de massa verde (PMVF) e seca (PMSF) de forragem e peso seco da raiz (PSR). Observou-se efeito linear (p<0,05) decrescente para o NFV, TAlF, TAlH e para a TApF. Notou-se que a partir do quarto dia sem irrigação o capim massai teve queda na produção de 10,68 g vaso-1 para 2,66 g vaso-1 para os tratamentos de 4 e 10 dias respectivamente, indicando que essa espécie tem sua produção comprometida em curto período de déficit hídrico. Intervalos de irrigação superiores há quatro dias influenciam as características de crescimento e produção do capim massai

Live weight, carcass, and meat evaluation of Nellore, Curraleiro Pé-Duro, and their crossbred products in Piauí State

ABSTRACT The objective of this study was to evaluate live weight and carcass traits, from birth to slaughter, and meat quality of Nellore (NEL), Curraleiro Pé-Duro (CPD), and crossbred (F1) products in the state of Piauí, Brazil. Progenies from CPD, NEL, and their F1 crossbred (½ NEL + ½ CPD), a total of 252, males and females, from birth to 24 months of age, were evaluated in a comparative study in growth performance. The steers were sent to slaughter at 28 months of age and carcasses and meat quality were analyzed. After slaughter, carcass weight, dressing percentage and Longissimus dorsi area (rib eye area) were evaluated; an index was created by the relationship between these measures per hundred kg of chilled carcass produced. To assess meat quality, the shear force, water-holding capacity, color, brightness, pH, and cooking loss were investigated. Results obtained showed that month and year of birth were significant on growth, indicating influence of climatic variables. Nellore offspring was heavier than F1 and this was heavier than CPD throughout the study period, including the hot and cold carcass. No differences were found in dressing percentage among NEL and F1, but CPD and F1 showed a rib eye area and index significantly higher than NEL. The meat from CPD group presented a stronger red coloration than the others, but there was no significant difference in the remaining meat qualitative variables among the three groups. Curraleiro Pé-Duro and F1 crossbred produce more meat per 100 kg of carcass than Nellore in natural pasture of Piauí State