The intestinal microbiota of birds presents a wide variety of commensal microorganisms distributed from the crop, permeating through the duodenum, jejunum, ileum, caecuses and colon. They act in the metabolism of nutrients in the diet, generating important products for the balance of the microbiome and preservation of the intestinal organs tissue wall, resulting in better yield, nutritional development of the birds and satisfactory productivity for the producer. The guarantee of such results is only possible when there is knowledge about the microbiome, the nutritional requirements of the birds, the quantity and adequate time for food supply, environmental conditions and water supply. These are important points in this process of maintaining the symbiosis between host and microorganisms. This literature review aims to point out the main aspects of the intestinal microbiota of production birds, elucidating the intestinal anatomy of birds, contributing to the productive performance with emphasis on the set of commensal microorganisms present, elucidating the products resulting from the performance of these agents and which additives performance improvement has been used in animal nutrition to guarantee the health of the microbiome, based on the main agents present in the gastrointestinal tract of birds of zootechnical interest.

Currently, dysbiosis, rupture of the intestinal barrier and inflammation have become concerns of industrial poultry, since they culminate in the physiological and productive impairment of birds. The objective was to discuss the role of the intestinal microbiota of birds in animal development, as well as to highlight the benefits and/or losses caused by these microorganisms. The methodology adopted was a descriptive study, with a bibliographic review of scientific papers published in different indexed bases, with a time frame of the last decades. It was found that the use of sequencing the RNA ribosomal gene (rRNA) 16S is an important tool to identify and enumerate the intestinal bacteria present in production birds. Regarding the composition of the microbiota, in the small intestine there are mainly Lactobacillus, Streptococcus, Enterococcus, Bifidobacterium, Bacterioides, Clostridium, Fusobacterium and coliforms. In the large intestine, Lactobacillus, Bacterioides, Proteobacteria, Bacillus, Clostridium and Bifidobacterium. In the small intestine, bacteria participate in metabolism by improving nutrient absorption, hydrolyze polysaccharides to produce short-chain fatty acids, which will be absorbed and participate in important metabolic pathways in the supply of carbon and energy sources to birds. Despite the benefits of the microbiota in promoting a stable intestinal environment, in unfavorable situations, such as inadequate breeding, it can act as pathogens, produce toxic metabolites and impair the productive performance of birds.

O milho (Zea mays L.) é um produto agrícola bastante cultivado no mundo, sendo que no Brasil é de grande importância para o agronegócio nacional, além de ser base de sustentação para a pequena propriedade. A aplicação de manipueira como fertilizante pode ser via foliar ou solo, sendo que a foliar é a mais viável, porque além de ser fonte suplementar de nutrientes pode servir como defensivo agrícola, ou seja, pode apresentar duplo efeito. A presente pesquisa objetivou analisar o uso da manipueira como fertilizante foliar na cultura do milho. O experimento foi conduzido em condições de campo, entre os meses de junho e agosto de 2010, no município de Lagoa Seca, PB. O delineamento experimental utilizado foi blocos causalizados, composto por cinco tratamentos, distribuídos em quatro blocos. Após 90 dias do plantio foram avaliadas as variáveis, altura da planta, altura de inserção da 1ª espiga, diâmetro do caule, comprimento do caule, número de folhas e área foliar. Os resultados foram submetidos à análise de variância e da regressão polinomial, sendo utilizado o teste F para verificar a significância dos efeitos. Os resultados indicaram que, a aplicação da manipueira em suas diferentes dosagens proporcionou ganhos de fitomassa em todas variáveis estudadas, havendo diferença estatística (p < 0,01) entre os tratamentos utilizados. A manipueira mostrou-se eficaz na adubação, via foliar, da cultura do milho, pois, todas as variáveis analisadas apresentaram valores superiores à testemunha absoluta.

The poultry industry evolved and reached high production performance, with several zootechnical techniques that contributed to the current scenario, including ambience, genetics and diet - all contributing and optimizing the digestive system of the birds. The gastrointestinal tract is a system with several functions and attributions within the organism, among them, digestion of the host, immunity and proper functioning of the system. The gut microbiota has direct effects on metabolic processes and subsequently on the performance of birds. Issues related to microbiota have acquired relevance both for the maintenance and modulation of these microorganisms. One of the maneuvers used to manipulate the intestinal microflora was the use of antibiotics, acting as growth promoters; however, this type of additive, due to sanitary pressure, should be abolished in the coming years, which makes other options appear on the scene, among them, phytogenic additives. Among the latter, essential oils have gained prominence for their beneficial activity in the microbiota as well as their natural composition and non-residual impacts on the process. Based on this, the aim was to review the guidelines that affect the intestinal microbiota in poultry.

The intestinal health makes it possible to maintain the efficient and sustainable physiology of the gastrointestinal tract of birds. The gastrointestinal tract has digestive, absorptive, metabolic, immunological and endocrine functions. Thus, impaired intestinal health can systematically affect various functions of the body. The objective of this review is to characterize the importance of intestinal health in broilers. The methodology adopted was the bibliographic study, and the information obtained from documentary sources. Gastrointestinal functionality was found to be the stable state in which the microbiome and intestinal tract exist in symbiotic balance, with animal welfare and performance not restricted by intestinal dysfunction. Gastrointestinal functionality has gained prominence in poultry because of the growing demands for economic efficiency, welfare, food security, reduction of environmental impacts and restrictions on the use of performance enhancing antimicrobials. Among the essential factors for bird intestinal health are the care of chicks in the first weeks of life, enteric diseases, the quality of feed ingredients and the use of additives that favor the preservation of enterocytes. The intestinal health of broiler chickens is an important characteristic to be maintained and observed in poultry production. A healthy gut is necessary so that the bird can properly perform the physiological processes inherent in its organism and express its productive potential, with diet manipulation being a promising strategy for positively modulating the intestinal microbiota of poultry. The use of agents that have trophic effects on intestinal mucosa contributes to improve the digestibility of nutrients, growth performance and intestinal health of broilers.