Desempenho, produção de metano entérico e avaliação de locais para estimação da digestibilidade ruminal de bovinos alimentados com dietas à base de cana-de-açúcar e silagem de milho

• Ano de defesa: 2012
• Autor(a) principal: Mariz, Lays Débora Silva
• Orientador(a): Valadares Filho, Sebastião de Campos
• Banca de defesa: Pereira, Luiz Gustavo Ribeiro , Marcondes, Marcos Inácio
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Zootecnia
• Departamento: Genética e Melhoramento de Animais Domésticos; Nutrição e Alimentação Animal; Pastagens e Forragicul
• País: BR
• Palavras-chave em Português: Silagem de milho; Cana; Digestibilidade
• Palavras-chave em Inglês: Corn silage; Sugar cane; Digestibility
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::PRODUCAO ANIMAL
• Link de acesso: http://locus.ufv.br/handle/123456789/5709

The present work was developed starting from three experiments described in two chapters. In chapter one, the first experiment, aimed on evaluate the fermentative profile of sugarcane silage treated or not with calcium oxide, the experiment two, evaluate intake, the apparent digestibility and the performance of cattle fed on to different diets constituted of 60% on the follow roughage in the dry matter (DM) basis: corn silage (CS); in natura sugar cane (INC); in natura sugar cane for the first two feeding periods and corn silage at the final feeding period (INC/CS); untreated sugar cane silage (CS 0%); 0,4% calcium oxide treated sugarcane silage (CS 0,4%) and 0,8% calcium oxide treated sugar cane silage (CS 0,8%) based on natural matter. At experiment one, were made 15 experimental silos, five per treatment (CS0%, CSO,4% and CS 0,8%), that were opened after 41 days of fermentation. The dry matter recovery on the sugar cane silage presented quadratic comportment, being the maximum value 94,02% estimated at the treated silage with 0,81% calcium oxide. The gas loss presented straight decreasing comportment according with the calcium oxide level raise. The yeast population presented quadratic comportment, being the lower population 3,32 ufc/g of fresh forage estimated at the 0,39% calcium oxide treatment. At experiment 2, was used 30 crossbred cattle Zebu-European, with 24 to 36 months and with average body initial weight 343±7,0 kg. The experiment was accomplished at completely randomized design, with 6 treatments and 5 replications. The experiment was divided in three periods of 28 days. The diets digestibility were evaluated at the final experimental period, using the indigestible neutral detergente fibrer (iNDF) to evaluate the fecal excretion. The DM intake, organic matter (OM), crude protein (CP), ether extract (EE), neutral detergente fiber (NDF) and nonfiber carbohydrates (NFC) were higher (P<0,05) for fed animals with corn silage diets. The animals fed with in natura sugar cane and INC/CS presented higher (P<0,05) DM, OM, EE, NDF and NFC intake than those fed with sugar cane silage. The diets with corn silage presented lower (P<0,05) digestibility coefficients for DM, OM and NFC than the in natura sugar cane diets. The digestibility of the DM, OM, CP, EE, NDF and NFC at the sugar cane silage untreated and treated with 0,8% calcium oxide were the same. The treated sugar cane silage diet with 0,4% calcium oxide presented lower OM and NDF digestibility than the CS0% and CS0,8% diets. The corn silage fed animals presented daily medium weight gain greater (P<0,05) than the other treatments animals. The medium daily weight gain that received INC/CS was lower (P<0,05) than the corn silage fed animals, but it was greater on 25,8% than the sugar cane diet fed animals. The sugar cane diets provided lower (P<0,05) daily medium gain. Was conclude that the corn silage based diets provided better performances than those fed in natura sugar cane or sugar cane silage, and that the roughage change on the final third is benefical, because raise the gain on 25,8% so can reduce the time to reach the same final weight and that the calcium oxide use reduce the dry matter loss, but the used levels wasn t efficient to change the animals intake. At chapter two, aimed on evaluate the intake, the ruminal and intestinal digestibility obtained with diets samples collected in reticulum or omasum, and the rates of passage, digestibility and enteric methane production on diets containing corn silage (CS) and in natura sugar cane (INC) or ensilage. Five crossbred cattle were used, fistulated in the rumen and with 24 to 36 months, weighting 336±16,6 kg, distributed on 5x5 Latin square design, being the five treatments compound on 60% diets on the follow roughage in the DM basis :corn silage (CS); in natura sugar cane(INC); untreated sugar cane silage (CS 0%); 0,4% calcium oxide treated sugar cane silage (CS 0,4%); 0,8% calcium oxide treated sugar cane silage (CS 0,8%) natural matter based. To evaluate the digestibility, were made six sampling feces, reticular and omasal digestas with intervals of twelve hours, using to estimate the constituents outflow in reticular and omasal digestas, the two marker systems (iNDF, to solid phase and Co-EDTA to the liquid phase), being the fecal production estimated with the iNDF. To measure the digestion rate were made two ruminal dissections, being the first after the morning diet supply and the other one before the diets supply. The methane production was estimated by the sulfur hexafluoride gas tracer method during five consecutive days. The data was analyzed using the SAS PROC MIXED. The greater daily methane productions (P<0,05) was observed on the in natura sugar cane and corn silage than the sugar cane silage but when expressed on animal product unit, was lower (P<0,05) on corn silage and in natura sugar cane than the sugar cane silage diets. The reticular and omasal digestas presented similarities (P>0,05) to evaluate the ruminal digestibility of the DM, OM, CP, NDF and NFC. However the ruminal digestibility of EE and intestinal digestibility of PB and EE differed (P<0,05) between the collects locations. The corn silage diet presented the greater (P<0,05) ingestion rate of DM, passage rate of DM and NDF and provided greater animal intake. The ingestion and passage rates of DM and NDF were similar on the CS 0% and CS 0,4% diets. The CS 0,8% diet presented ingestion and passage rate of DM and NDF lower than CS 0,4%. Concludes that the better quality diets presented lower methane production per animal product unit and greater digestibility and passage rates. In addition observed that the omasal digesta collect presented better consistency than the reticular digesta.