RESUMO
Decreases in the use of antibiotics and anticoccidials in the poultry industry have risen the appearance of necrotic enteritis (NE). The purpose of this study was to evaluate the effect of a Bacillus direct-fed microbial (DFM) on growth performance, intestinal integrity, NE lesions and ileal microbiota using a previously established NE-challenged model. At day-of-hatch, chicks were randomly assigned to three different groups: Negative control (NC), Positive control (PC) challenged with Salmonella Typhimurium (day 1), Eimeria maxima (EM, day 13) and Clostridium perfringens (CP, day 18-19), and Bacillus-DFM group (DFM) challenged as the PC. Body weight (BW) and body weight gain (BWG) were measured weekly. Total feed intake (FI) and feed conversion ratio (FCR) were evaluated at day 21. Liver samples were collected to assess bacterial translocation and blood samples were used to measure superoxide dismutase (SOD) and fluorescein isothiocyanate-dextran (FITC-d). Intestinal contents were obtained for determination of total IgA and microbiota analysis. NE lesion scores (LS) were performed at day 21. Chickens consuming the DFM significantly improved BW and had a numerically more efficient FCR compared to PC at day 21. Additionally, there were no significant differences in FCR between the DFM group and NC. Furthermore, the DFM group showed significant reductions in LS, IgA and FITC-d levels compared to the PC. However, there were no significant differences in SOD between the groups. The microbiota analysis indicated that the phylum Proteobacteria was significantly reduced in the DFM group in comparison to PC. At the genus level, Clostridium, Turicibacter, Enterococcus, and Streptococcus were reduced, whereas, Lactobacillus and Bacillus were increased in the DFM group as compared to PC (p < 0.05). Likewise, the DFM significantly reduced CP as compared to PC. In contrary, no significant differences were observed in bacterial composition between NC vs. DFM. In addition, beta diversity showed significant differences in the microbial community structure between NC vs. PC, and PC vs. DFM. These results suggest that the dietary inclusion of a selected DFM could mitigate the complex negative impacts caused by NE possibly through mechanism(s) that might involve modulation of the gut microbiota.
RESUMO
We examined rubella vaccination trends, rubella surveillance, and disease patterns for the Americas, Mexico, and the United States, to evaluate the impact of hemispheric rubella control on rubella elimination in the United States during 1997-2004. In 1997, 130,375 rubella cases were reported in the Americas, with 38,042 reported in Mexico. Over the next 7 years, a rubella control initiative resulted in the administration of approximately 110 million rubella-containing vaccine doses in Latin America, with 77.7 million doses administered within Mexico. By 2004, the number of reported rubella cases had declined to 3103 in the Americas and 698 in Mexico. Concurrently, the number of rubella cases in the United States fell from 817 during 1997-1999 to <25 cases/year from 2001 onward, with loss of seasonality and geographic clustering, despite no change in vaccination rates. Implementation of rubella control strategies in the Americas, particularly in Mexico, appears to have facilitated rubella elimination in the United States.
Assuntos
Programas de Imunização/tendências , Programas Nacionais de Saúde/tendências , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/prevenção & controle , Vacinação/tendências , Adolescente , Adulto , América Central/epidemiologia , Criança , Feminino , Humanos , América Latina/epidemiologia , Masculino , México/epidemiologia , Rubéola (Sarampo Alemão)/imunologia , Vacina contra Rubéola/administração & dosagem , Vacina contra Rubéola/imunologia , Estados Unidos/epidemiologiaRESUMO
Desde 1976 Kilian y Theilade individualizaron a Heamophilus segnis como una especie bien diferenciada de otros haemophili del grado parainfluenzae, con base en su dependencia del factor V y no al factor X, así como a algunas características metabólicas, particularmente su lenta fermentación de la glucosa y sacarosa. Un carácter notable es su alta proporción de G + C en el DNA y su excepcional morfología colonial; aunque parásitos de la placa dentaria humana no se han relacionado con la formación de bascesos en el Sistema Nervioso Central, as semejanza de algunos otros Haemophilis. El hallazgo de cuatro abscesos, en cuyo contenido se aisló Haemophili segnis, únicamente en el cerebro de un paciente de 17 años del Hospital Infantil de México con una evolución fatal, amerita esta comunicación