Dinâmica da comunidade bacteriana em volumosos a base de palma forrageira e feno de capim-buffel

• Ano de defesa: 2021
• Autor(a) principal: Santos, Daiane Gonçalves dos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraíba; Brasil; Zootecnia; Programa de Pós-Graduação em Zootecnia; UFPB
• Palavras-chave em Português: aerobiose; Cenchrus ciliares; Escherichia coli; metataxonomia; Nopalea cochinilifera Salm Dyck; qualidade nutricional; CNPQ::CIENCIAS AGRARIAS
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/123456789/34705

The aim of this study was to evaluate the bacterial community dynamics of different proportions of forage cactus and buffel grass hay as a function of the period of exposure to air. The experimental design used was completely randomized, in a 5 x 5 factorial arrangement (five levels of palm and buffel grass hay x five times of exposure to air), with five replications. The treatments consisted of forage cactus levels, ranging from 20 to 100% in natural matter, evaluated at times 0, 3, 6, 12 and 24 hours. The variables analyzed were: internal and surface temperature; chemical composition; Escherichia coli population and bacterial community by 16S ribosomal rRNA gene metataxonomy. There was an interaction between the levels of palm in the diet and the time of exposure to air (P<0.001) for internal and surface temperature, pH and population of Escherichia coli. It was found that the lower the level of palm, the higher the internal and surface temperature of forages, reaching the peak temperature after 12.19 and 11.87 hours of exposure to air, respectively. In all treatments, the pH was considered as having low acidity, between 5.70 and 7.38. The peak of E. coli population growth was after 16.06 hours of exposure to air. For chemical composition, there was interaction (P<0.001) of palm levels and time of exposure to air for dry matter, crude protein, buffer capacity, soluble carbohydrates and ammonia nitrogen. The time of exposure to air significantly influenced (P<0.001) the values of organic matter, mineral matter and ether extract, for the values of neutral detergent fiber it observed a significant effect (P<0.001) for the levels of palm. An increase in microbial richness and uniformity of all treatments was noted after six hours. The most abundant genera were Weissella, Lactobacillus, Bacteroides, Pseudomonas, Sphingobacterium and Sphingomonas. A higher microbial quality was observed in the diet with 100% palm, with a predominance of Weissella, Lactobacillus and Leuconostoc. With 80% of buffel grass hay there was an apparent abundance of Pseudomonas, Sphingomonas and Sphingobacterium. Thus, it is concluded that forage cactus in combination with buffel grass hay increases the proliferation of microorganisms with pathogenic potential, when exposed to air for periods longer than 6 hours, negatively influencing the microbiological quality and chemical composition of forage.