The objective of this study was to evaluate changes in the bacterial community in sugarcane silage, in distinct soil types along the storage period. We depicted the bacterial community associated with sugarcane, before and after ensiling, through a massive sequencing of the gene 16S rRNA using MiSeq platform. The ensilage process shifted the composition of the bacterial community from the heterofermentative lactic acid bacteria Leuconostoc to bacteria belonging to the genera Acinetobacter, Ralstonia and Novosphingobium. However, this shift did not convey statically significant differences in alfa diversity metrics. In addition, similarity percentage analysis showed that the bacterial Operational Taxonomic Units that were primarily responsible for the observed differences were Leuconostoc, Pseudomonas, Acinetobacter, Ralstonia, Fructobacillus, Novosphingobium, Lactobacillus, Burkholderia and Clostridium sensu stricto 1. The storage period was the most important factor responsible for changes in the bacterial community of silages. Results confirmed that the type of soil did not influence the dissimilarity found among samples.

-The objective was to evaluate the effects of corn silage supplemented with 1-propanol or inoculated with L. buchneri on the ruminal fermentation profile, digestibility, and production traits of lactating Holstein cows. Whole-corn plants were harvested at 350 g/kg dry matter (DM) and packed in nine bag silos (13 t/silo). At ensiling, two treatments were applied: control (no additive; six silos) and L. buchneri inoculation with 1 × 10 5 cfu/g (three silos). Feeding started after 247 days of storage; one L. buchneri and two control silos were opened in each experimental period. Twenty-one multiparous Holstein cows (~33 kg/day of milk) were allocated to seven balanced 3 × 3 Latin squares with 21-day periods (14 days of adaptation). The experimental diets contained (DM basis): 80 g/kg cottonseed, 95 g/kg citrus pulp, 180 g/kg soybean meal, 90 g/kg corn grain (ground), 25 g/kg minerals and vitamins premix, and 530 g/kg of corn silage. Source of corn silage was the only difference between experimental treatments: control, L. buchneri, or control silage supplemented with 1-propanol (10 g/kg of diet DM). The 1-propanol was dissolved in water (1:1) and sprinkled onto the ration during mixing, immediately before each feeding. Dry matter intake, nutrient digestibility, milk yield, and composition were not affected by treatments. Cows fed 1-propanol had greater concentrations of 1-propanol in the rumen fluid, higher concentration of glucose, and lower concentration of non-esterified fatty acids in blood plasma. Corn silage inoculated with L. buchneri at 1 × 10 5 cfu/g does not affect silage fermentation, ruminal fermentation profile, or milk production. Supplementation of 1-propanol at 10 g/kg affects the ruminal fermentation profile without affecting feed intake and milk production of mid-lactating dairy cows.Key Words: aerobic stability, alcohol, heterofermentative inoculant, voluntary feed intake Revista Brasileira de Zootecnia

Aos meus pais Marisa e Ivanor pelo apoio incondicional, por acreditarem que tudo isso seria possível. Ao meu irmão Hermes, meu parceiro de sempre. Obrigado pela tua preocupação. A minha querida avó Noeli, o anjo que está sempre do meu lado. Aos meus nonos Venilde e Inácio por sempre estarem na torcida do meu sucesso. Aos meus irmãos da República Aroeira. Vocês me deram uma família em Piracicaba, vocês dividiram comigo todas as minhas vitórias e angústias, vocês fizeram toda a diferença. Muito obrigado. Ao meu orientador Professor Paulo Fernando Machado por todo apoio, orientação e os valiosos ensinamentos. A Professora Marcia Endres pela recepção na Universidade Minnesota e pela amizade. Realmente, foi uma experiência inesquecível. Aos meus amigos João Pedro, Helen, Janielen e Renata, parceiros do grupo de pesquisa por todas as risadas, auxílios e ensinamentos. Foram bons anos ao lado de vocês. Ao meu amigo Marcos Busanello, essencial para condução deste trabalho. Obrigado por tudo. Ao Mateus, Sônia e Siane, irmãos que ganhei durante minha estadia nos Estados Unidos. Ao Júlio e ao Kaíke, parceiros da Clínica do Leite, que foram fundamentais na obtenção dos dados para realização deste trabalho. A todos os funcionários da Clínica do Leite pela amizade, risadas e parceria. A ESALQ pelos valorosos anos de ensinamentos e desafios. Por me proporcionar momentos e amizades que levarei para sempre em minha vida. A Universidade de Minnesota por me receber e proporcionar essa grande experiência. Aos grandes amigos que por Piracicaba fiz ao longo desses quase sete anos, são tantas pessoas que faltaria espaço para citá-los. Cada um de vocês sabem o quanto foram importantes nessa caminhada. A CAPES pela concessão da bolsa de estudo no Brasil e no exterior.

The objective of the present study was to evaluate the quality of refrigerated raw milk produced by 912 farmers in the Western part of Santa Catarina State, Brazil. The parameters analyzed were fat, protein, lactose, solids nonfat (SNF) content, standard plate count (SPC) and somatic cell count (SCC). A comparative analysis study with data from 2009 and 2010 was also conducted, which has shown that SCC influenced on the physico-chemical results. It was also observed that in 2010 the values for SCC were higher than in 2009, out of the limits recommended by the legislation until 2011. The SPC values were well above the maximum level accepted, indicating high contamination of milk with aerobic mesophilic microorganisms. The data collected indicated that only 4.9% of the producers sampled in 2009 and 8.1% in 2010 were in compliance with the standards enforced by a new legislation of January 2012. There was also increase on the milk fat content as SCC increased, which was not observed with other milk components. Lactose had a gradual reduction as SCC increased. On the other hand, SNF content did not correlate with SCC variance. These results demonstrate the urgent need of improvement in milk production and better technical orientation of milk producing properties to reach higher quality standards in Santa Catarina.

Efeitos da estratégia de descarregamento e inclusão dietética de silagem de milho no valor nutritivo de rações completas para vacas em lactação Maximiliano Henrique de Oliveira PasettiDissertação apresentada para obtenção do título de Mestre em Ciências. Aos meus amigos da pós graduação: