Qualidade da silagem do algodoeiro arbóreo [Gossypium hirsutum L. r. marie-galante (Watt) Hutch.]

Abstract

There are several species of plants with forage potential in the semiarid region of Brazil, but the chemical composition and nutritional value are generally unknown. The objective of this study was to characterize the silage of the arboreal cotton [Gossypium hirsutum L. r. marie-galante (Watt) Hutch.] regarding chemical-bromatological aspects, qualitative parameters of silage, fractionation of carbohydrates and nitrogen compounds, in vitro dry matter digestibility and ruminal degradation kinetics using in vitro methodologies. The cultivation area of this forage is located in the Experimental Farm of UFRPE / Garanhuns Academic Unit. For ensiling the arboreal cotton was collected when it reached a height of 50 centimeters (120 days after a cut). After collection, the material was minced in a forage chopping machine to reduce particle size. The experiment was conducted in a completely randomized design with a 4x2 factorial arrangement, with four treatments, with five replications each. Two forms of the material were ensiled, one that did not go pre-dried, and one that went through pre-drying (4h). Each form of silage received four treatments, 1- without additives (SA); 2- with bacterial inoculant (CI); 3- with 2% ground corn (CMM) and 4- with bacterial inoculant + 2% ground corn (CMM + I). The bacterial inoculant used were strains of Lactobacillus plantarum and Pediococcus pentosaceus (1g / ton of forage mass). And after 30 days of ensilage, the silo was opened. Took place Chemical-bromatological analyzes, qualitative parameters of ensilage, carbohydrate and protein fractionation, in vitro digestibility of dry matter and ruminal fermentation kinetics were determined by in vitro gas production technique. The dry matter contents of the pre-dry silage were higher than the in nature silage. The crude protein contents in nature silage were higher in the treatments without additive and inoculant. In the in vitro digestibility of dry matter, both in nature silage and pre-dry silage, the inoculant treatments, ground corn and the most inoculant ground corn presented the highest values. All treatments of pre-dry silage were superior to those of in nature silage for the variable total digestible nutrients. The total volume of gas observed was higher in the pre-dry silage treatment with ground corn. Due to the presented nutritional value, regardless of the addition or not of additives, the arboreal cotton silage shows potential to be used in the feeding of ruminants.