Intake, performance and nutrient digestibility of sheep fed sugarcane treated and ensiled with calcium oxide or urea

Abstract

-The objective of this study was to evaluate intake, performance and nutrient digestibility of sheep supplemented with sugarcane ensiled with four levels of calcium oxide (0.0, 0.8, 1.6 and 2.4%) and urea (1.5%), on a natural matter basis. Twenty castrated Santa Ines lambs with 24.09 kg average weight were housed in individual 1.5 m 2 pens, distributed in a completely randomized design. The diet supplied had a roughage:concentrate ratio of 70:30 and the experimental period lasted 77 days, of which 14 days were used for adaptation to the diet and three 21-day periods for data collection. No differences were observed for the average daily intake of dry matter, ether extract, neutral detergent fiber, neutral detergent fiber corrected for ash and protein, total carbohydrates, hemicellulose and total digestible nutrients. The treatment with urea showed differences for the intake (kg/day) of crude protein, acid detergent fiber and non-fibrous carbohydrates. There was no effect of diets on the digestibility of dry matter, ether extract, neutral detergent fiber, acid detergent fiber or total digestible nutrients, but there was a quadratic effect for total carbohydrates and increasing linear effect for non-fibrous carbohydrates. The calcium intake increased as the levels of calcium oxide in the sugarcane were elevated. The calcium:phosphorus ratio in the silage of calcium oxide was different from the silage with urea and control. No effect was observed for the performance characteristics of sheep. Sugarcane silages with calcium oxide levels of up to 2.4% or with urea do not improve the intake or weight gain of sheep.

Nutritional profiles of three genotypes of sugarcane silage associated with calcium oxide

“…The reduction of protein contents with the addition of CaO is thought to result in dilution of CP because this component is absent from the additive in question, which adds to the loss of nitrogen compounds during volatilization. This assumption was confirmed by Magalhães et al (2013), who evaluated the chemical composition and fermentation loss of sugarcane silages with different Brix degrees, both with and without CaO. In this study, the increase in Brix in the sugarcane decreased linearly with the CP content of the material that was ensiled, which shows that as the material matures, there is a reduction in its dietary value that results from the increases in the constituents of the cell wall and total sugars.…”

“…The addition of alkaline additives to the cell wall of the fodder solubilizes the fibrous components, as stated in the study of Brienzo et al (2016). The implication is that alkaline environment helped to increase the digestibility of sugarcane, possibly by reducing ADF and LIG, which corroborates findings of Magalhães et al (2013). Huang et al (2016) evaluated the effect of additives in the treatment of sugarcane bagasse (SCB) and reported that the C 2 H 5 ONa pre-treatment showed the best effect on hydrolysis of SCB.…”