Cinética ruminal in vitro de silagem de azevém em diferentes tempos de desidratação da massa verde e diferentes estádios fenológicos

Abstract

The objective of this work was to evaluate the parameters related to in vitro ruminal kinetics of ryegrass silage at different drying times of the biomass at its following levels: vegetative (cut and ensile; cut and ensile after 4 hours of drying; cut and ensile after 7 hours). hs) drying); Pre-flowering (cutting and ensiling; cutting and ensiling after 4 hours of drying); Flowering (cut and ensile). The work was conducted at the Food Analysis Laboratory of the Federal Technological University of Paraná, Campus Dois Vizinhos, where they were prepared or cultivated and then mixed with the ruminal node collected from 4 fistulated Jersey cattle. As were allocated to the penicillin vial for volume and pressure reading of the following pressure ranges 1, 2, 3, 6, 8, 10, 12, 16, 20, 24, 30, 36, 48, 72, 96, 120 and 144 hours after incubation. The parameters of in vitro rumen kinetics were estimated by mathematical model, taking into consideration: latency period, gas volume produced by the fast and slow degradation fraction and degradation rate of the fast and slow degradation fraction, besides the total gas volume. produced by treatment. An in vitro degradation curve was also estimated, taking into account the return between the gas production time and 144 hours. Controls that demonstrated satisfactory results between the total gas production volume and in vitro rumen kinetic parameters were 7-hour pre-drying vegetative stage silage with 22,7209 mL / 0.1 g DM, not pre-stage. flowering with 4 hours pre-drying with 16.9112 mL / 0.1g DM and no pre-flowering stage with 7 hours pre-drying 21.7171 mL / 0.1g DM. Controls with higher dry matter content presented higher degradation rates and were ideal for the use of large animals for feeding.