0668 Effects of method and storage time on the nutritive value of sugarcane for dairy cattle. (1st October 2016)

• Record Type: Journal Article
• Authors: Fonseca, F. T.; Lima, L. M.; De Oliveira, R. M.; Domingues, F. N.; Bernardes, T. F.
• Is Part Of: Journal of animal science. Volume 94(2016)Supplement 5
• Page Start: 319
• Page End: 319
• Publication Date: 2016-10-01
• Subjects: cut-and-carry system -- forage harvesting -- tropical forage; Livestock -- Periodicals; Livestock; Electronic journals; Periodicals; 636.005
• DOI: 10.2527/jam2016-0668
• Languages: English
• ISSNs: 0021-8812

Abstract

Abstract: Fresh chopped sugarcane is an important forage source for dairy cattle in tropical environments; however, daily harvest has been a major constraint for producers. Therefore, the objective of this study was to evaluate two storage methods (stem and whole plant) in different times on the nutritive value, microbial counts, and DM losses to extend the intervals between harvests. Two experiments were performed for 2 yr (Experiment 1 and 2). In both experiments, 288 plants of sugarcane were manually collected during the crop harvesting window. Leaves were removed from 144 plants and other part remained intact (whole plants). Sugarcane stems and plants were split into 18 bunches (8 stems or plants per bunch) and placed on the ground in a barn at ambient temperature for 0, 2, 4, 6, 8, and 10 d. For each day of evaluation, three bunches of each treatment were weighed to determine DM losses. Afterward, bunches were chopped to assess nutritive value and microbial counts (bacteria, yeasts, and molds). In experiment 2, additionally to these parameters was assessed the leaf carbon balance (CO2 uptake during photosynthesis minus CO2 loss during respiration) in sugarcane plants. Treatments were arranged in a completed randomized design with repeated measurements over time. The data were analyzed by the mixed-model method using the MIXED procedure (SAS Institute, 2004). The means were compared using a Tukey test at the 5% probability. In both experiments, DM and NDF concentrations and in vitro DM digestibility were lower in stems compared with whole plants. Storage time had an inconsistent effect on chemical composition and microbial counts. Only DM losses were affected by the interaction between method and storage time. Whole plants reached losses more than 90 kg MS/ton at 6 and 8 d in the experiment 1 and 2, respectively. On the other hand, stems showed the maximum DM losses at 10 d (55.1 and 35.0 kg MS/ton for experiment 1 and 2, respectively). The carbon balance of leaves in whole plants was negative due to respiration losses from 2 d storage, which might explain the rise in DM losses. Overall, sugarcane stems is the most effective method to store forage under a cut-and-carry system because stems have greater nutritive value and take up less space in the barn with a long duration of aerobic stability (10 d).