Produção e composição bromatológica de cultivares de milheto forrageiro sob alturas de crescimento e residual

• Autor(a) principal: BASTO, Débora de Carvalho
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000003dfs
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tde/954
• topic: 1. FDA; 2. FDN; 3. Forragem; 4. Manejo; 5. (Pennisetum glaucum (L.) R.Br.); 6. Proteína bruta e rendimento forrageiro; 1. Pennisetum glaucum-produção-avaliação 2. Milheto - composição bromatológica; 1. ADF; 2. Crude protein; 3. Forage management; 5. Forage yield; 6. NDF; 6. (Pennisetum glaucum (L.) R.Br.); CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::PRODUCAO ANIMAL

The best height of forage at time of entry into pasture and the height of forage millet residue for grazing are still controversial. This experiment was conducted at the Department of Animal Production of the Veterinary School, of Federal University of Goias, in Goiania-GO, from January to May 2009, and aimed to evaluate the productive potential and the chemical composition of three cultivars of forage millet (Pennisetum glaucum (L.) R. BR.) under different heights of entry and of the stubble. The 27 treatments consisted of the combinations of three varieties of millet - ADR 500, H733/07 and H729/07, allocated in plots, three heights at entry (0.50, 0.60 and 0.70 m) and three heights of stubble (zero, 0.10 and 0.30 m) allocated in sub-plots with four replications, totaling 108 experimental units. A randomized complete block design, with split plots andfour replications in a 3 x 3 x 3 factorial arrangement was used. Green matter total yield (GMTY), dry matter total yield (DMTY), average production of dry matter per cutting, production of dry matter of stubble with zero, 0.10 and 0.30 m, average rate of forage accumulation, and rate of forage accumulation of stubble "zero" 0.10 and 0.30 m were determined. The contents of crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were also determined. Green matter total yield (GMTY) differed depending on the height at entry (HE) and height of stubble, with average values of 25.2: 28.0 t ha-1 and 28.5 and 20.4; 30.6 and 30.7 t ha-1, estimated for the HE and stubble, respectively. The dry matter production increased in the extent that the height at entry and the height of the stubble increased. The average production of dry matter per cutting for the cultivars was approximately 2840 kg ha-1/DM. The average accumulation of forage millet was 61.74, 58.29 and 63.59 kg ha-1/DM for cultivars ADR-500, ADR-500 hp, 729 and 733, respectively. Regarding chemical composition, the dry matter content did not differ among the cultivars evaluated. The CP did not differ in function of the cultivars and HE. The residue of 0.10 and 0.30 m, interactions among cultivar x HE x cutting, averaging 14.0% of CP were observed. The NDF had triple interaction: cultivar x HE x cutting in the stubbles of 0.10 and 0.30 m, with average values of 57.6, 58.6 and 57.7%, and 58.4, 61, 6 and 57.7%, respectively. ADF differed in relation to the cultivars, with values of: ADR-500-35- 5, 729 - 37.6 and 733 - 37.9%. As for the residue of 0.10 m, there was an interaction in relation to HE x cutting, with values of 30.0, 31.7 and 25.8% for the HE of 0.50, 0.60 and 0.70 m. As for the residue of 0.30 m triple interactions were observed: HE x cultivar x cutting, with average rates of (ADR-500) - 31.7%, (729) - 32.0%, and (733) - 32.7%, respectively. Based on the values of dry matter and chemical composition, all cultivars showed potential for use in animal feed.