Época de sobressemeadura de gramíneas anuais de inverno e de verão no capim-tifton 85: valor nutritivo

Abstract

RESUMOConduziu-se o experimento na UNESP-Jaboticabal, no período de inverno-primavera-verão de [2001][2002], objetivando determinar os teores de proteína bruta (PB), parede celular (FDN, FDA, lignina, celulose e hemicelulose) e a digestibilidade in vitro da matéria orgânica (DIVMO) no capim-Tifton 85 exclusivo e sobressemeado com aveia preta, milheto e sorgo-sudão. Os tratamentos testados foram: milheto+aveia preta; AG2501C+aveia preta, sobressemeados nas áreas de Tifton-85, em 19-06 ou 02-07-2002, e capim-Tifton 85 (Testemunha). O delineamento experimental foi de blocos casualizados, com três repetições. Os teores de PB foram maiores na primeira avaliação quando comparada às demais. Observou-se aumento nos teores de FDN, FDA e lignina, e comportamento inverso nos valores de DIVMO, em relação aos períodos de crescimento, nas duas épocas de semeadura. Os teores avaliados de PB, parede celular e DIVMO apresentaram variação em função da composição botânica e morfológica, no decorrer das avaliações e épocas de semeadura.Termos para indexação: Aveia preta, constituintes da parede celular, digestibilidade in vitro da matéria orgânica, proteína bruta, triticale. ABSTRACTThe experiment was conducted at UNESP-Jaboticabal on the 2001-2002 winter-spring-summer period to evaluate the crude protein, cell wall (NDF, ADF, cellulose, hemicellulose and lignin) contents, and in vitro organic matter digestibility (IVOMD) of the Tifton 85 alone or overseeded with annual species (oat, pearl millet, and sorghum Sudan grass-SS). It was evaluated the followings treatments: pearl millet plus bristal oat; SS AG2501 C plus bristeal oat, overseeded on Tifton 85 area on 06/19/02, or 07/02/02, and Tifton 85. The data were analyzed according a randomized block design with three repetitions. The CP was highest on the forage harvested at the first evaluation. The cell wall content increased, and IVOMD decreased, in relation to the plant development in booth seeding time. The CP, cell wall contents, and IVOMD changed during the evaluations and seeding time due to the botanical and plants morphological composition.

Brachiaria brizantha control by using fluazifop-p-butil on Tifton 85 pasture formation

“…The results of ADF, NDF, CP, and IVDDM of Tifton 85 (Table 1) are similar to those described in the literature for this grass species (Gonçalves et al, 2002;Moreira et al, 2006), which shows that although fluazifop-p-butyl compromises the regrowth of Tifton 85 plants, it does not influence the nutritional quality of this plant. CP -crude protein; NDF -neutral detergent fiber; ADF -acid detergent fiber; IVDDM -in vitro dry mass digestibility; ns -not significant at 5% probability using F test.…”

Use of a conditioning unit at the haymaking of Tifton 85 overseeded with Avena sativa or Lolium multiflorum

“…Such dry matter reduction, during the coldest periods of the year, could be supplemented with annual overseeded forages that are adapted to cold weather, such as oat and ryegrass. In grazing areas, the overseeded management causes significant increase in the quantity and quality of forage, according to trials carried out by Reis et al (2001) and Moreira et al (2006).…”

Nitrogen and carbohydrate fractions on Tifton-85 pastures overseeded with annual winter and summer forage species in different seasons

“…Higher values of TC were observed in the fifth growth period as a result of the increase in the stem fraction, and also in the cell wall content (Moreira et al, 2006b) and the decrease in the CP content (Table 1).…”

“…The proportion of indigestible cell wall (fraction C) in each production cycle (Table 4) ranged from 15.6 to 24.5, 14.2 to 19.8, 14.8 to 18.3, 13.5 to 19.5 and 10.9 to 18.4 of the proportion of TC of the first to the fifth cycles, respectively. Thus, the variation of the indigestible portion of the cell wall was small (Moreira et al, 2006b). Fraction C consists basically of the cell wall associated with lignin, which exerts a negative effect from the nutritional viewpoint.…”