Identification of Brucella sp. isolated in Brazil from 1976 to 2013 by Bruce-Ladder PCR

Background: Brucella sp. are the causative agents of brucellosis, an infectious disease that affects various species of animals and can be transmitted to humans through direct contact with infected animals, indirectly by the ingestion of rawmilk products, and during the handling of strains or infected material in the laboratory. Being a zoonosis, the detection of Brucella species in animals is essential for the prevention of the disease in humans and to perform a good program of control in infected herds. This study aimed at identifying Brucella field strains isolated from 1976 to 2013 in Brazil, using the modified Bruce-Ladder method, to evaluate the performance of this technique. Materials, Methods & Results: Eighty-three strains of Brucella sp. were included in the study, i.e. 21 reference strains (nine B. abortus, one B. canis, four B. melitensis, two B. ovis and five B. suis) and 62 field strains (six B. canis, one B. suis and 55 B. abortus). For the identification of the genus and/or species of Brucella, biochemical and physiological tests, including MacConkey-agar growth, glucose fermentation, haemolysis, catalase, oxidase and urease tests, nitrate reduction, citrate utilization, H2 S production and CO2 requirement, were performed. Genomic DNA was extracted from pure cultures through heat-lysis of bacterial cultures and the genus was confirmed by a genus-specific PCR (bcsp31 target gene), before performing the modified Bruce-Ladder PCR for the confirmation of the Brucella species. No problems of specificity were observed with the Bruce-Ladder PCR. However, the 1,682 bp fragment was not systematically amplified, even after several modifications such as the concentration of mix components, annealing temperatures and time. Therefore, an individual PCR using primers specific to this fragment was needed for complete identification of some strains. Also, only one kind of Polymerase gave the best results. All Brucella reference strains and negative controls gave the expected results. All field strains previously identified as B. abortus, B. canis and B. suis by biochemical and physiological tests were confirmed by the modified Bruce-Ladder PCR. All isolated Brucella abortus presented a Bruce-Ladder PCR profile expected for field strains, excluding the vaccine strains. Discussion: The modified Bruce-Ladder PCR identified properly all Brucella species (reference and field strains) and proved to be a reliable technique, thus facilitating the identification of the species in the laboratory, reducing the manipulation of these bacteria and the associated danger. Albeit the difficulties of amplification of one fragment for some strains, when using the multiplex technique, this method is fast and without risks after inactivation of the strains. Most studies on animal brucellosis in Brazil were only based on serological tests without identification of the pathogen; while the knowledge of the particular species and/or biovars that occur in Brazil, as well as their distribution, is important to monitor the spread of Brucella among sensitive species and among farms. Our results showed also that B. abortus is still the predominant species isolated in cattle in Brazil. The knowledge of the species that occur in Brazil can help to identify the source of infection and the measures of control to be applied, while it is also very important to trace the dispersion of strains among farms

Progressive in vivo detection of wooden breast in broilers as affected by dietary energy and protein

Wooden breast (WB) myopathy was investigated in broilers fed varying energy and protein at early ages. Correlation analyses were conducted between echogenicity of ultrasound images (US) of breast muscle from live birds and WB after slaughter. A total of 1,000 Cobb 500 one-day-old male chicks were fed on five dietary programs with eight replicates of 25 birds each, in a completely randomized design. Control feeds (commercially used ME and ideally balanced amino acids) or low-density feeds (low EP, with reductions of 50 kcal/kg ME and 0.20% dig. Lys compared to the control) were formulated. Feeds were provided in different periods: 1 to 7 d, 8 to 14 d, 15 to 21 d or 22 to 28 d. All broilers were fed a common basal diet thereafter until 49 d. Images using US were obtained once a week from all individuals and WB scored from one slaughtered bird per replication (0, normal; 1, mild hardening in the upper breast muscle; 2; moderate hardening in the upper and/or lower breast muscle; 3, severe hardening; 4, severe hardening with hemorrhagic lesions and yellow fluid). Blood was collected for enzyme investigation from the weekly slaughtered bird. Broilers had lower BWG and higher FCR when fed low EP feeds, regardless of the period fed when compared to the control (P < 0.001). Growth compensation, however, occurred afterwards such that all birds presented similar performance at the end. At 14, 21, and 28 d, broilers previously fed low EP feeds had lower WB scores (P < 0.001) compared to birds fed the control; however, both groups presented increased WB scores after 28 d. Wooden breast was positively correlated with breast echogenicity at 21 d (r = 0.31), 28 d (r = 0.43), 35 d (r = 0.21) and 42 d (r = 0.39). In conclusion, dietary energy and protein affected the development of WB scores in broilers and breast US images can be used as an early predictor of WB

Incubação artificial: aspectos qualitativos e quantitativos a serem considerados na produção comercial de pintos.

A avicultura comercial, nas últimas décadas, vem se consolidando no mercado internacional de produção de carne e ovos. Inúmeros são os fatores que estão envolvidos com esse crescimento, e um deles é o processo de incubação artificial. Este método, além de possibilitar a incubação de grande quantidade de ovos simultaneamente, também garante a qualidade do pinto e sua disponibilidade para alojamento, maximizando o desempenho das aves e disponibilizando aos produtores matéria prima de qualidade. Sendo o incubatório uma peça fundamental para a produção industrial de pintos, é essencial que todas as suas etapas sejam criteriosamente estudadas e conhecidas, pois o sucesso da incubação depende de um acompanhamento e controle rigorosos. É importante o conhecimento do desenvolvimento embrionário, para melhor entender quais as medidas e cuidados que devem ser tomados durante a incubação, de forma que a evolução embrionária dos pintos não seja comprometida. Estes fatores devem ser padronizados dentro do sistema de controle para que, desta forma, a indústria possa disponibilizar ao mercado pintos de qualidade que apresentem um excelente desempenho zootécnico.The commercial poultry industry in recent decades, has been consolidated in the international market of production of meat and eggs. There are many factors that are involved with this growth, one is the process of artificial incubation. This method, besides enabling the lot of eggs incubation simultaneously, also ensures broilers quality and their availability for accommodation, maximizing bird performance and making available to farmers high quality raw material.Being the hatchery a cornerstone for the industrial production of chicks, it is essential that all steps are carefully studied and known, because the success of incubation depends on a strict monitoring and regulatory control. It is important the knowledge of embryonic development, to better understand what steps and precautions that should be taken during incubation, so that the embryonic development of the chicks is not compromised.These factors should be standardized within the control system so that in this way, the industry can provide the quality chicks market to produce an excellent growth performance

Incubação artificial: aspectos qualitativos e quantitativos a serem considerados na produção comercial de pintos.

A avicultura comercial, nas últimas décadas, vem se consolidando no mercado internacional de produção de carne e ovos. Inúmeros são os fatores que estão envolvidos com esse crescimento, e um deles é o processo de incubação artificial. Este método, além de possibilitar a incubação de grande quantidade de ovos simultaneamente, também garante a qualidade do pinto e sua disponibilidade para alojamento, maximizando o desempenho das aves e disponibilizando aos produtores matéria prima de qualidade. Sendo o incubatório uma peça fundamental para a produção industrial de pintos, é essencial que todas as suas etapas sejam criteriosamente estudadas e conhecidas, pois o sucesso da incubação depende de um acompanhamento e controle rigorosos. É importante o conhecimento do desenvolvimento embrionário, para melhor entender quais as medidas e cuidados que devem ser tomados durante a incubação, de forma que a evolução embrionária dos pintos não seja comprometida. Estes fatores devem ser padronizados dentro do sistema de controle para que, desta forma, a indústria possa disponibilizar ao mercado pintos de qualidade que apresentem um excelente desempenho zootécnico.The commercial poultry industry in recent decades, has been consolidated in the international market of production of meat and eggs. There are many factors that are involved with this growth, one is the process of artificial incubation. This method, besides enabling the lot of eggs incubation simultaneously, also ensures broilers quality and their availability for accommodation, maximizing bird performance and making available to farmers high quality raw material.Being the hatchery a cornerstone for the industrial production of chicks, it is essential that all steps are carefully studied and known, because the success of incubation depends on a strict monitoring and regulatory control. It is important the knowledge of embryonic development, to better understand what steps and precautions that should be taken during incubation, so that the embryonic development of the chicks is not compromised.These factors should be standardized within the control system so that in this way, the industry can provide the quality chicks market to produce an excellent growth performance

Utilization of ultrasonography to detect the Wooden Breast myopathy in live broilers submitted to feed restriction

Este estudo objetivou avaliar a utilização da ultrassonografia no diagnóstico in vivo de wooden breast (WB) em frangos de corte submetidos à restrição alimentar. Foram utilizados 1.800 frangos de corte machos Cobb x Cobb 500 distribuídos em 6 tratamentos, com 12 repetições de 25 aves cada, em um delineamento inteiramente casualizado. Os tratamentos consistiram em restrições de 50, 60, 70, 80, 90% da quantidade de ração fornecida em relação ao consumo ad libitum diário do tratamento controle, de 8 a 49 d. Semanalmente, as aves foram pesadas para avaliação de desempenho e foram submetidas à ultrassonografia para determinar a ecogenicidade do peito, em que os valores de cinza foram calculados a partir do histograma gerado de cada imagem. A profundidade do peito também foi mensurada. Semanalmente, de 7 a 49 d, uma ave por unidade experimental (UE) foi abatida para avaliação visual dos escores de WB, bem como para coleta de amostras de peito para análises sorológicas e de qualidade de carne. Aos 49 d, foram abatidas 5 aves por UE para avaliação do rendimento de carcaça, cortes comerciais e ocorrência de WB Os peitos foram avaliados em escores: peito normal (0); endurecimento suave na parte cranial (1); endurecimento da parte cranial e caudal (2); endurecimento severo de todo o peito (3), endurecimento severo com presença de lesões hemorrágicas e exsudato (4). O efeito das restrições alimentares sobre desempenho e os escores de WB foi avaliado através da análise de variância. Os escores de WB foram considerados variáveis independentes e também correlacionados com as medidas de ultrassom do peito, qualidade de carne, medidas histomorfométricas e perfil sorológico das aves. O desempenho produtivo e a ocorrência de WB reduziram linearmente (P 0.05) as feed restriction was applied. The WB occurrence presented linear response to growth performance and it was lower on treatments with higher feed restrictions. Echogenicity and depth increased with WB severity (P < 0.05). From 21 to 49 d, the WB scores 3 and 4 also had higher cooking loss, fiber diameter, serum enzymes, whereas fiber density per area was lower (P < 0.05) compared to normal breasts (score 0). Ultrasound images of broilers breast can be adequately utilized to predict in vivo the WB of birds

Utilization of ultrasonography to detect the Wooden Breast myopathy in live broilers submitted to feed restriction

Este estudo objetivou avaliar a utilização da ultrassonografia no diagnóstico in vivo de wooden breast (WB) em frangos de corte submetidos à restrição alimentar. Foram utilizados 1.800 frangos de corte machos Cobb x Cobb 500 distribuídos em 6 tratamentos, com 12 repetições de 25 aves cada, em um delineamento inteiramente casualizado. Os tratamentos consistiram em restrições de 50, 60, 70, 80, 90% da quantidade de ração fornecida em relação ao consumo ad libitum diário do tratamento controle, de 8 a 49 d. Semanalmente, as aves foram pesadas para avaliação de desempenho e foram submetidas à ultrassonografia para determinar a ecogenicidade do peito, em que os valores de cinza foram calculados a partir do histograma gerado de cada imagem. A profundidade do peito também foi mensurada. Semanalmente, de 7 a 49 d, uma ave por unidade experimental (UE) foi abatida para avaliação visual dos escores de WB, bem como para coleta de amostras de peito para análises sorológicas e de qualidade de carne. Aos 49 d, foram abatidas 5 aves por UE para avaliação do rendimento de carcaça, cortes comerciais e ocorrência de WB Os peitos foram avaliados em escores: peito normal (0); endurecimento suave na parte cranial (1); endurecimento da parte cranial e caudal (2); endurecimento severo de todo o peito (3), endurecimento severo com presença de lesões hemorrágicas e exsudato (4). O efeito das restrições alimentares sobre desempenho e os escores de WB foi avaliado através da análise de variância. Os escores de WB foram considerados variáveis independentes e também correlacionados com as medidas de ultrassom do peito, qualidade de carne, medidas histomorfométricas e perfil sorológico das aves. O desempenho produtivo e a ocorrência de WB reduziram linearmente (P 0.05) as feed restriction was applied. The WB occurrence presented linear response to growth performance and it was lower on treatments with higher feed restrictions. Echogenicity and depth increased with WB severity (P < 0.05). From 21 to 49 d, the WB scores 3 and 4 also had higher cooking loss, fiber diameter, serum enzymes, whereas fiber density per area was lower (P < 0.05) compared to normal breasts (score 0). Ultrasound images of broilers breast can be adequately utilized to predict in vivo the WB of birds