Composição química-bromatológica e avaliação cinética digestiva da silagem e da planta inteira de arroz em diferentes estádios fenológicos

Abstract

Brazilian rice consumption is mostly supplied by the southern region of the country (76.6%), with the state of Rio Grande do Sul responsible for 68.70% of production, despite the reduction of planted area, rice showing increases in the total produced, which, combined with a history of imports and the gradual decrease in consumption per capita, predisposes to the occurrence of greater availability of the product in the market. These weather-related conjectures that impair the quality of the product promote the need for diversification of the use of rice and its co-products in order to maintain producers' incomes. The production of whole crop rice silage (WCRS) is one of the options that arises to take advantage of the productive potential of this crop. The objective of this work was to define the ideal moment of cutting the entire rice plant for silage, for use in animal feed. Four different phenological stages of the cultivar BRS QUERENCIA were tested with 85 (R4), 91 (R6), 99 (R7) and 105 (8) R days after emergence and ensiled in micro silos for 45 days. The in vitro dry matter digestibilities (IVDMD), the nutritional characteristics and the fermentation profile of the silage were carried out. An increase in WCRS (<0.05) was observed for dry matter (DM), non-fibrous carbohydrate content, starch plus pectin and total digestible nutrients (TDN). During plant aging, the values of neutral detergent insoluble fiber corrected for ash (NDFc) and crude protein (CP) (<0.05) were also decreased. There was an improvement in IVDMD as the plant stages progressed. It can be concluded that with the maturation increase of the rice plant an improvement in its quality, both in the fermentative profile, in the nutritional characteristics as in the IVDMD, is due to the increase of the participation of grains in the plant.