The infectious bronchitis virus (IBV) was detected for the first time in Brazil by Hipólito in 1957 in chickens sold life in the municipal market of Belo Horizonte, MG, when commercial poultry production was just starting in that country. The Massachusetts (Mass) serotype was identified. However, the clinical disease was only observed in 1975, when poultry production was intensely growing. The extensive outbreak produced the classical condition in layers and breeders, affecting egg production and quality, whereas broilers presented respiratory and "nephritis-nephrosis" signs. The disease rapidly spread to all poultry-producing regions in the country, and in 1979, both the imports and the manufacturing of live vaccines against IB strains Mass, H120 and H52, were licensed. In 1980, inactivated vaccines were introduced. Molecular techniques, particularly PCR, started to bed in the identification of IBV. A retrospective analysis showed that, up to 1989, the main IBV strain circulating in Brazil was Mass. However, other studies shows the presence of a wide diversity of IBV strains in Brazil since the first strains were isolated, even before vaccination was introduced. Most researchers agree that the incidence of IBV different from Mass has increased, including of exclusively Brazilian genotypes, different from those described in other countries. Indeed, during the last few years, the number of genotypical variants has been much higher than that of the classical Mass serotype. Clinically, in addition of the classic presentations, atypical forms such as testicular atrophy and stones in the epidydimis associated to low fertility have been described. Serological techniques started to be used in vaccination monitoring and as a diagnostic tool. Serological response standards were developed, and have shown to be very useful to determine the expected profile in vaccination programs and when clinical disease is suspected. However, the immuno-enzymatic test ELISA is the most frequently used around the world due to its convenience. These situations led service people working in the field to suspect that vaccination programs using Mass strains were not providing the required protection because of the presence of variant strains. Some argue that this was expected, particularly in layers and breeders, because Mass-type vaccines have been used for a long time, whereas most agree that the emergence of variants is the primary cause of the increasing severity of the disease in the field. This is supported by the results using Ibv genotyping as diagnostic tool, independently of phenotype (pathotype x immune system x environment). Other argues that broiler carcass downgrading rates in processing plant are not consistent with the increase in IB clinical severity. Seroconversion in non-vaccinated flocks is acknowledged, but it occurs sporadically and not necessarily correlated with disease outbreaks. There is a general agreement that IBV has shown high variability in Brazil in terms of genotype, pathotype, and serotype. However, research should emphasize IBV phenotypical characteristics using birds as biological model.

Salmonella Enteritidis (SE) emergiu como um grande problema avícola e de saúde pública no Brasil a partir de 1993. Os estudos epidemiológicos, incluindo a fagotipagem e sonda complementar de rRNA, sugerem a entrada de SE no Brasil via importação de material genético avícola contaminado, provavelmente no final da década de 80. As taxas de crescimento da avicultura brasileira na década de 90 criaram condições favoráveis para a manutenção e proliferação da SE nos plantéis avícolas. Além disso, o uso indiscriminado de antibióticos em aves, particularmente as quinolonas, encorajou a manutenção de lotes positivos para SE. As cepas de SE isoladas de aves têm mostrado alta sensibilidade aos antibióticos de uso comum em avicultura, incluindo as quinolonas. Entretanto, o aumento da resistência antimicrobiana e multirresistência tem sido observado em cepas de origem humana. Os últimos levantamentos realizados no ano de 2001 continuam a mostrar que a SE em materiais avícolas é o principal sorovar responsável pelas infecções humanas. Embora as carcaças de frangos apresentem altas taxas de contaminação por SE, são os ovos e seus derivados - principalmente a maionese caseira - os principais responsáveis pelos surtos humanos. O uso de vacinas específicas em poedeiras e reprodutoras tem se mostrado uma ferramenta auxiliar no controle de SE. O procedimento mais indicado para o controle de SE na avicultura está na aquisição e produção de lotes livres do agente. As rações e matérias primas de origem animal parecem não ser tão importantes na perpetuação do problema de SE, porém, os roedores parecem ser reservatórios ambientais importantes de SE em granjas contaminadas.

In Brazil, Salmonella enteritidis (SE) emerged as a serious problem in poultry and public health as from 1993. Epidemiological studies, including fagotyping and complementary rRNA probe, suggest that SE entered Brazil via the importation of contaminated poultry genetic material, probably at the end of the eighties. The rate of growth of the Brazilian poultry industry in the nineties created favorable conditions for the maintenance and proliferation of SE in poultry production. Also, the indiscriminate use of antibiotics in chickens, especially quinolones, encouraged the maintenance of SE positive flocks. SE strains isolated from chickens have shown great sensitivity to the antibiotics commonly used in poultry, including the quinolones. However, an increase in antimicrobial resistance and multiresistance has been observed in strains of human origin. The latest surveys carried out in 2001 continue showing the presence of SE in poultry materials as the main serovar responsible for human food infections. Although chicken carcasses show high levels of contamination by SE, it is eggs and egg products - mainly home made mayonnaise - which are the products mostly responsible for outbreaks in humans. The use of specific vaccines in layers and parent stock has been used as an auxiliary tool in the control of SE. However, the most indicated procedure for the control of SE in poultry is the acquisition and production of SE free flocks. Animal feed and raw materials of animal origin are apparently of lesser importance in the perpetuation of the SE problem, although rodents appear to be important environmental reservoirs of SE in contaminated farms.

Dois sistemas de bebedouros utilizados na criação avícola, pendular e chupeta (nipple), foram estudados objetivando avaliar a qualidade microbiológica da água fornecida às aves, em relação à presença de coliformes totais e fecais, aeróbios mesófilos, bolores e leveduras. Realizaram-se coletas de água no primeiro, 14, 28 e 42 dias de idade, sendo os dias de amostragem divididos em três períodos, de acordo com o horário de limpeza dos bebedouros pendulares: primeira, antes da limpeza; segunda, logo após a limpeza e terceira, ao meio dia. Os bebedouros avaliados apresentaram índices de contaminação em relação ao NMP de coliformes fecais acima dos limites estabelecidos pela Portaria do MS-Brasil. As contagens para UFC de bolores e leveduras obtidas para bebedouros pendulares apresentaram índices de contaminação maiores do que os chupeta. Em uma segunda etapa do estudo, foi avaliado o efeito da cloração constante sobre a qualidade microbiológica da água, usando os mesmos parâmetros anteriores. Foram instaladas bombas dosadoras de cloro em cada galpão reguladas para manter concentração de 2mg/L de cloro residual livre. A cloração contínua da água melhorou a qualidade microbiológica em relação ao NMP de coliformes totais e fecais nos bebedouros avaliados. Quanto aos aeróbios mesófilos, os bebedouros apresentaram-se fora dos padrões estabelecidos pela Portaria MS-Brasil, sendo o chupeta o que apresentou melhor desempenho. O bebedouro chupeta apresentou índices de contaminação da água inferiores aos apresentados pelos pendulares. Mesmo assim, foram considerados fora dos padrões para água potável.

Two drinker systems used by commercial broiler growers, the bell drinker type and the nipple drinker, were studied aiming to evaluate the microbiological quality of the water supplied to the birds in relation to occurrence of total and fecal coliforms, mesophilic aerobic, moulds and yeast. The water samplings were taken on the 1st, 14th, 28th and 42th days of age. The days of sampling, in accordance with the cleaning schedule for the bell type drinkers, were divided into three periods: before the cleaning, right after cleaning and at noon. The evaluated drinkers presented patterns of contamination in relation to the most probable number (mpn/100ml) of fecal coliforms above that of the limit number established by the Ministry of Health, Brazil. The counts for mould and yeast (cfu/mL) obtained from bell type drinkers showed a higher pattern of contamination when compared to the nipple drinker. In a second stage of the study, the effect of constant flow chlorination was evaluated on the microbiological quality of the water, using the same standard parameters as previous described. Dosage measurement pumps of chlorine were installed in each poultry house and managed to keep a concentration of 2mg/l of free residual chlorine. Continuous flow water chlorination improved the microbiological quality in relation to the MPN of total and faecal coliforms in the evaluated drinkers. In relation to the mesophilic aerobic, the evaluated drinkers showed to be out of the standards established by the MH-Bresil, while the nipple type was the drinker that presented the best performance. The nipple drinker showed lower patterns of water contamination in relation to that presented in the bell type drinkers. Even thought, the water contamination were out of the established standard for drinking water.