PRODUÇÃO, BROMATOLOGIA E DEGRADAÇÃO RUMINAL DA FORRAGEM DE CEREAIS DE INVERNO CULTIVADOS EM DIFERENTES SISTEMAS DE MANEJO

Abstract

Winter cereals have been used for centuries as an alternative animal feed and perform well in the field, being used in intercrops and singly. The consortium between grasses is still little studied, thus requiring information to help the producer in choosing forage and also in consolidating the seed market, since piracy is a very common practice for these cereals. The objective of the work was to evaluate the productive characteristics of oat cultivars (black and white) subjected to cuts at different stages of development. The experiments aimed to evaluate the productive and bromatological characteristics of different oat cultivars (white and black) grown alone or in intercropping, harvested at different stages of development, according to treatment designation: TamPic: 90% white oat GMX Tambo + 10 % GMX Picasso black oats; InvPicGau: 90% GMX Invernia white oats + 5% GMX Picasso black oats + 5% UPF Gaudéria white oats; TamGau: 30% GMX Tambo white oats + 70% UPF Gaudéria white oats and Pic: 100% GMX Picasso black oats. In the first experiment, the design was randomized blocks, in a 4x6 factorial scheme, with four combinations of winter forages with 5 replications, cultivated alone or in intercropping, associated with six successive cuts that took place when the plants reached 32.0 cm in height and were lowered to 12.0 cm. In the second experiment, the design was randomized blocks, in a 4x2 factorial scheme, with four combinations of winter forages cultivated alone or in a consortium associated with two successive cuts in the vegetative and full vegetative phase and/or two cuts in the pre vegetation phase. flowering and mealy grain phase, all materials were subjected to three successive cuts (first and second cut in the vegetative and full vegetative phase), upon reaching a plant height of 32.0cm with lowering to 12.0cm, with a third being carried out sequentially cut, being harvested in the pre-flowering phase and/or mealy grain phase, aiming to produce hay or pre-dried hay and silage, respectively. Bromatological analyzes evaluated dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (LIG) and mineral matter content (MM). Ruminal degradation of the dry matter of the samples was carried out at times of 48,72 and 168 hours. The morphological composition of the plants was also carried out, which were separated into leaves, stem and reproductive part. In the first experiment, the oat consortium allowed, with the progress of the six cuts, a greater participation of leaves in the physical structure of the plant, which consequently determined lower levels of acid detergent fiber compared to the isolated cultivation of black oat cv. Picasso. The intercropping of black oats with white oats is recommended, as in general, they had greater stability during the production cycle under productive or qualitative parameters of the forage produced. In the second experiment, black oat cv. Picasso grown alone had a lower share of leaves and consequently greater shares of stem and reproductive structure, when harvested in the reproductive phase. Under the conditions of the present study, it is recommended to use combinations of black oat and white oat cultivars as they promote better distribution of forage production and greater balance of nutritional value throughout the production cycle. The different forage combinations were superior in physical composition of the plant and consequently in chemical composition when harvested in the pre-flowering phase compared to the floury grain phase, however with lower accumulation of dry biomass per unit area. In general, all forages, under productive or qualitative parameters of the forage produced, whether cultivated in a consortium or alone, can be managed in a sequence of three successive harvests, with two cuts in the vegetative and full vegetative phase, followed by a third cut in the growth phase pre-flowering or mealy grain.