Perdas, características fermentativas e valor nutritivo da silagem de capim-elefante contendo subprodutos agrícolas

Abstract

RESUMO -O experimento foi conduzido para avaliar as perdas por gases e efluente, as características fermentativas e o valor nutritivo de silagens de capim-elefante contendo como aditivos farelo de mandioca, casca de café ou farelo de cacau.Utilizou-se delineamento inteiramente casualizado, em esquema fatorial 3 × 4, com três aditivos avaliados em quatro níveis (0, 10, 20 e 30% da matéria natural), cada um com cinco repetições. O material foi acondicionado em silos de PVC por 60 dias. Após abertura dos silos, foram realizadas pesagens para determinação das perdas, pela quantificação da produção de efluente e das perdas por gases. Amostras foram coletadas para posteriores análises de nitrogênio amoniacal e pH e da composição químico-bromatológica. A adição dos aditivos provocou aumento dos teores de matéria seca, e farelo de mandioca foi o aditivo mais eficiente no controle das perdas por efluente e gases. A adição de farelo de mandioca, casca de café e farelo de cacau garantiu altas taxas de recuperação de MS, enquanto o farelo de mandioca e o farelo de cacau favoreceram a redução dos valores de pH e os teores de nitrogênio amoniacal, respectivamente, refletindo na melhoria do perfil de fermentação das silagens. As silagens contendo farelo de mandioca apresentaram maiores teores de nutrientes digestíveis totais e garantiram os menores teores de fibra em detergente neutro, fibra em detergente ácido, celulose e lignina.A adição de farelo de cacau ao capim-elefante no momento da ensilagem contribui para o aumento dos teores de nitrogênio total, porém aumenta os teores de nitrogênio insolúvel em detergente neutro e em detergente ácido.Palavras-chave: efluente, ensilagem, gases, Pennisetum purpureum, resíduo Losses, fermentation characteristics and nutritional value of elephant grass silage containing agricultural waste ABSTRACT -The experiment was conducted to determine losses by gases and effluent, fermentation characteristics and nutritional value of elephant grass silage containing cassava meal, coffee hulls and cocoa meal. It was used a completely randomized experimental design in a 3 × 4 factorial scheme, with three additives evaluated in four levels (0, 10, 20 and 30% of natural matter), each one with five repetitions. The material was ensiled in PVC silos for 60 days. After opening of the silos, weightings were carried out for determination of losses through the quantification of effluent production and also by losses by gases. Samples were collected for subsequent analyses of ammonia nitrogen content and pH values, as well as the chemical-bromatological composition. The additive addition caused an increase in the dry matter contents and cocoa meal was the most efficient additive to control effluent and gas losses. The addition of cassava meal, coffee hulls and cocoa meal assured high recovery rates of dry matter, while cassava meal and cocoa meal favored the reduction of pH values and ammonia nitrogen contents, respectively, resulting in silages fermentation profile improvement. The silages containing cassava...

Fermentation losses and chemical composition in mixed silages of elephant grass and cassava peels with mango residue

“…These results can be related to the lower DM content of the silages of the present study. Andrade et al (2010) found that the inclusion of 14.2% of the cocoa meal was sufficient to inhibit effluent loss, different from the present study in that the addition of only 10% of mango residue allowed lower effluent losses (6,89 kg/ton NM). Negrão et al (2016) verify decrease of effluent and gas losses using rice meal in the silage of Brachiaria decumbens.…”

“…These lower values could be explained by the low content of DM (19.9%) and MM (2.40%) of the additive used, while the reduction of the NFC content accompanied the decrease in DM. The minimum DM content obtained in this study was close to that registered by Andrade et al (2010) of 29.7% DM, when evaluating elephant grass ensiling with 20% cocoa meal; and by Azevedo et al 2017, of 29.8% DM, using 16.1% mango residue in the elephant grass silage. However, it was superior to the elephant grass silages evaluated by Rêgo et al (2010) 27.9% DM, with the addition of 16% by-product of the mango processing; by Ferreira et al (2015) that obtained 27% DM with addition of 14% dehydrated cashew residue and by Ferrari Junior et al 2009which added 10% citrus pulp and reached 24.9% DM.…”

“…Quadratic behavior was observed in the DM loss and DM recovery, with a maximum DM loss of 22.1% and, consequent, minimum DM recovery of 78.9%, with the inclusion of 21.1% and 21.4% of mango residue, respectively. This result was lower than that recorded by Andrade et al (2010) of 99.8% DM recovery with the inclusion of 20% of the cocoa meal. According to Pacheco et al (2014), the DM recovery rate is negatively correlated with effluent and gas losses in the silages, which explains the reduction of DM recovery with the inclusion of up to 21.4% of the additive.…”

Use of acids as additives in sugarcane silage

“…Samples from the silos were taken to determine the chemical composition (Silva and Queiroz, 2002), pH, and N-NH 3 (Campos et al, 2004). The loss of total dry matter (DM) and the loss due to gas production were calculated (Andrade et al, 2010). The effluent was determined by measuring the difference in the weight of the sand and silo prior and after ensiling in relation to the amount of green matter.…”

Silagem da ponta de cana-de-açúcar com resíduos da agroindústria da mandioca

“…ANDRADE et al (2010), usando farelo de mandioca, farelo de cacau ou casca de café em silagens de capim Elefante, observaram que o farelo de cacau usado no nível de 14,23% foi o resíduo mais eficiente em reduzir a produção de efluentes. Entretanto, para o farelo de mandioca só foram observados resultados positivos quando o nível foi de 25,63%.…”