Atributos do valor nutritivo do sorgo forrageiro submetido a adubação orgânica em sistema Agroecológico

Abstract

The animal and plant production system in Brazil has been intensifying more and more over the years, in response to the growth of the world population, which demands food from diverse origins, in such a way that the country is responsible for supplying both of the internal and external markets. Thus, the aim of this work was to evaluate nutritional components in forage plants subjected to organic fertilization in an agroecological system and intended for feeding ruminants. This work was developed at the Agricultural Science Center of the Federal University of Northern Tocantins (CCA/UFNT), located in the municipality of Araguaína - Tocantins. In the study, evaluations of the nutritional characteristics of Sorghum were carried out in an agroecological system subjected to organic fertilization with sheep manure and the legume sunn hemp (Crotalaria juncea). Chemical-bromatological analyzes were carried out on the whole plant, leaf and stem and for the content of crude protein (CP), dry matter (DM), ether extract (EE), mineral matter (MM) and neutral detergent fiber (NDF), neutral detergent fiber corrected for ash and protein (NDFcp), acid detergent fiber (ADF) and lignin (LIG). Thus, evaluations of cellulose and hemicellulose contents and calculations of total and non-fibrous carbohydrates were carried out. Determinations of neutral detergent insoluble nitrogen, acid detergent insoluble nitrogen, non-protein nitrogen and soluble nitrogen were also carried out. The fractions of carbohydrates in which were calculated following the methodology described by the Cornell program (CNCPS). Fertilization with Crotalaria was the one that stood out the most among the treatments in terms of nutritional constituents for use in ruminant nutrition, except for the percentages of CNF in the whole plant, and (% CHOT) of the A+B1 fraction. The CHOT content of the whole plant varied from 85.03% to 85.39%, with the first treatment referring to the control and the second treatment to Crotalaria + Sheep manure. All treatments using organic fertilizer sources resulted in improvements in the nutritional attributes of Sorghum.