Silagem de leguminosas à base de amendoim forrageiro e soja: características fermentativas e desempenho de bovinos de corte mestiços

• Autor(a) principal: Rosa, Lilian Oliveira
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1874
• topic: Bovino - Alimentação e rações; Nutrição animal; Soja - Silagem; Bovino de corte; Cattle - Feeding and feeds; Animal nutrition; Soy - Silage; Beef cattle; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA

Four experiments were conducted to evaluate the chemical composition, fermentation profile and dry matter recovery in mixed silages of marandu grass and forage peanut treated with a bacterial inoculant (Chapter 1); the chemical composition and fermentation profile of forage peanut silages treated with a bacterial inoculant and molasses powder (Chapter 2); the intake and total apparent digestibility of nutrients and the ruminal parameters in rumen-cannulatedsteers fed diets containing soybean, corn or sorghum silages, as well as the productive performance of beef cattle (Chapter 3). In Chapter 1, the forage peanut level (FP) × inoculant (I) interaction affected (P<0.05) the variables DM, OM, CP, EE, ADIN, TC, lignin, pH and butyric acid content; FP affected (P<0.05) variables NDF, ADF, cellulose, NFC, ammonia, lactic acid and acetic acid contents, and I affected (P<0.05) the ammonia content of the silages. Populations of LAB varied from 6.75 to 6.18 log cfu/g andfrom 6.85 to 6.41 log cfu/g in the silages without and with inoculant, respectively. The pH of the silages increased linearly (P<0.05) with the levels of FP, whereas the concentration of ammonia reduced linearly (P<0.05). The FP × I interaction affected (P<0.05) the effluent production and dry matter recovery, and FP affected (P<0.05) gas production. In Chapter 2, an interaction effect (P<0.05) between the level of molasses (M) and I was observed on variables OM, EE and NDF of the silages. Silages inoculated with 2% and 4% molasses showed the largest average populations of lactic acid bacteria: 5.64 and 5.51 log cfu/g, respectively. The M × I interaction affected (P<0.05) the pH and ammonia of the silages. The lowest mean values of pH and ammonia were detected in the silages of forage peanut inoculated with 4and 2% molasses, respectively. No effect (P>0.05) of the M × I interaction was observed for DM, OM, CP, TC, NDF, NDFap, NFC and TDN intakes by the animals supplemented with diets containing soybean silage exclusively as a forage source. The greatest mean values (P<0.05) of apparent digestibility of DM, OM, CP, TC and NFC were observed for the diet with100% corn silage (79.40%, 80.64%, 67.18%, 63.60% and 73.25%) andthe dietwith 50% soybean silage:50% corn silage (78.20%, 79.18%, 80.64%, 79.17% and 88.86%). The collection times had an effect (P<0.05) on the ruminal pH values of the diets, whose data fitted the following quadratic model: &#374;= 6.0452 + 0.2648 T 0.09955 T 2 , with R 2 = 83.42%.The lowest intakes of DM, OM, CP, NDF, NDFap, TC, NFC and TDN (P<0.05) were found in the animals fed diets containing soybean silage exclusively as a forage source. The highest mean values of apparent digestibility of DM, OM, CPand EE were observed (P<0.05) for diets containing soybean silage solely, sorghum silage only and 50%soybean silage:50% corn silage, which did not differ statistically from each other. Regarding productive performance, the greatest (P<0.05)average daily weight gains and carcass gains were observed for animals fed the diets containing corn silage, sorghum silage, 50% soybean silage:50% corn silage and 50% soybean silage:50% sorghum (Experiment 2).