Abstract
This study aimed to investigate the feasibility of utilizing kale juice residue as a feed. In experiment 1, in situ disappearance of three types of kale juice residue (raw : RK, dried at 90°C for 7 hours : DK, ensiled : SK1) and alfalfa hay (AH) was determined by the nylon bag technique using two rumen fistulated dry cows. The crude protein (CP) of kale juice residue was 17.2-18.9% (DM basis) which was as high as AH, but the neutral detergent insoluble crude protein content in CP of DK was higher than those of RK, SK1, and AH. The CP of RK and SK1 showed a lower disappearance rate from the bag than that of AH at the early incubation time, and the degradability was not different. On the other hand, the CP of DK compared to the other two juice residues showed a lower disappearance rate at any incubation time and lower degradability. The neutral detergent fiber of the three kale juice residues showed a higher disappearance rate than that of AH at any incubation time. In experiment 2, in order to investigate the digestibility and nutritive value of kale juice residue silage with lactic acid bacteria plus cellulase (SK2), four Japanese native goats were fed a diet consisting of SK2 and alfalfa hay cubes (1 : 1 on DM basis) or alfalfa hay cubes only. The total digestible nutrients, digestible energy and metabolizable energy (per DM) of SK2 was estimated to be 69.1%, 14.6 MJ/kg, and 13.4 MJ/kg, respectively. The nitrogen balance of the animals fed the diet containing 50% SK2 showed less urine nitrogen excretion and greater nitrogen retention than that fed alfalfa hay cubes only. These results indicate that kale juice residue has a potentially high nutritive value for ruminant feed.
