Cana-de-açúcar in natura ou ensilada com óxido de cálcio e uréia em dietas de ovinos

• Autor(a) principal: Pontes, Roberta Albuquerque Machado
• Data de Publicação: 2007
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5838
• topic: Silagem; Cana-de-açúcar; Uréia; Óxido de cálcio; Silage; Sugar cane; Urea; Calcium oxide; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL

The present study was developed from two experiments. In the first, the effects of calcium addition over the chemical composition, the sugar cane nutrients consume and digestibility at the cutting moment and 24 hours after it, were evaluated. 18 sheep without a defined bred were used, arranged in a totally randomized delineation, in a 2x3 factorial scheme, being two sugar cane storing time (0 and 24h) and three cal levels (0; 0,5 and 1% of the natural matter (NM)) with three repetitions per treatment. There was no interaction (P>0,05) between the storing time and the cal levels for the nutrients consume, expressed in g/day and in g/Kg of the live weight (LW). Excepting the ethereal extract (EE) in g/day, there was no significant difference for the consume in the different times and cal levels. The storing time and cal levels effect for the digestibility of the dry matter (DM) and of the organic matter (OM) were observed, registering the smallest values for the stored sugar cane, besides the decrease in the digestibility of the DM with the increase of the cal inclusion in the sugar cane. There was an interaction between the storing times and the cal levels for the digestibility of the rough protein (RP) and the fiber in a neutral detergent (FND). The cal usage and the storing times did not influence the total carbohydrates digestibility (TCD) and EE. In short, the cal doses addition, with the sugar cane supply immediately or after 24h after cutting were not efficient to increase the nutrients consume and digestibility. In the second experiment, the aim was to estimate the chemical composition and evaluate the consume, the nutrients digestibility and the in situ degradability of the sugar cane silage added or not with urea and/or calcium oxide. 18 sheep without a definite breed were used, arranged in a totally randomized delineation, in a 2x3x2 factorial scheme, being two urea/ammonia sulphate levels (o and 0,5% in the NM), three calcium oxide (0; 0,5 and 1% in the NM) in the ensilaging and, two periods, with three repetitions per treatment. The interaction between the urea and cal levels in the sugar cane ensilaging for the consume, expressed in g/day of the DM, OM, RP, EE, TCD, FND, non-fiber carbohydrates (NFC) and total digestible nutrients (TDN) were observed. For the treatments without urea, all the nutrients consume, excepting the FND and EE, increased with the addition of cal. In the urea presence, the DM, OM, RP, EE, TCD and FND consume, were smaller in the ensilaging without cal and the use of 0,5% of cal increased the FND consume. There was no interaction between the studied factors for the consume in g/day of the LW, OM, EE, TCD and FND. The cal addition increased the DM and RP consume in g/day of the LW, OM, EE, TCD and FND. In the absence of urea, the OM and TCD consume were increased with the inclusion of 1% of cal. In the cal absence, the OM, EE, TCD and FND consume were not influenced by the urea inclusion. There was a decrease in the OM, TCD and FND consume with the addition of 1% of cal together with urea. There was no interaction found between the studied factors for the DM, OM, RP, FND and TCD digestibility. Excepting the FND digestibility, which increased in 5,74 percentual units, a positive effect of the urea inclusion in the ensilaging was not verified. There was no effect in the cal levels in the nutrients digestibility. In the degradability in situ assay, it was seen that the cal use in the ensilaging reduced the FND indigestible fraction in approximately 33%. It was concluded that cal does not promote an increase in the nutrients digestibility. The urea levels studied did not provide consistent answers, confirming the need to more studies concerning the building of good quality silage for the sugar cane.