Acute intoxication with single oral dose of ochratoxin A (OTA) causes leukopenia, heteropenia, lymphopenia and lymphoid depletion in the bursa of Fabricius in broiler chicks / Intoxicação aguda com dose oral única de ocratoxina A (OTA) causa leucopenia, heteropenia, linfopenia e depleção linfoide na bolsa de Fabricius em pintainhos de corte

Ochratoxin A (OTA) is a mycotoxin produced by species of Penicillium and Aspergillus, agricultural product contaminants. Chronic and sub-chronic OTA intoxication by chickens ingesting contaminated feed, leads to health damages due to its hepatotoxic, nephrotoxic, cytotoxic, immunotoxic, gastrotoxic, and possibly carcinogenic effects. As there are few data on acute intoxication, the present study evaluated the effects of a single acute OTA intoxication dose on immunological and hematological parameters in chicks. Sixteen one-day-old chicks were used, separated into two groups (n=8). A single dose of OTA (1400 µg kg-1 body weight) was administered, via gavage, for the OTA group and one dose of sterile PBS for the control group. On the 13th day, blood samples were collected to assess hematological and biochemical parameters, and on the 14th day, euthanasia and collection of lymphoid organs were performed. The animals of the OTA group demonstrated a significant decrease in total circulating leukocytes (p<0.001) with heteropenia (p<0.001) and lymphopenia (p=0.023), decrease hematocrit (p=0.020), hemoglobin (p=0.032), and plasma IgA (p =0.044), and increased plasma uric acid level (p=0.045), in relation to the control group. In addition, the animals intoxicated with OTA showed depletion of lymphoid cells in the bursa of Fabricius (p=0.016), but not in the thymus or spleen (p>0.05), compared to the control. For the other parameters: total plasma proteins, plasma IgY levels, and anti-Newcastle Disease Virus (NDV) vaccine titers from matrices, there were no significant differences between the analyzed groups (p>0.05), although there was a worsening tendency in contaminated animals. In conclusion, even a single acute OTA intoxication at a high dose, leads to the suppression of the systemic immune response, also affecting some hematological or biochemical parameters in chicks.

Ocratoxina A (OTA) é uma micotoxina produzida por espécies de Penicillium e Aspergillus, contaminantes de produtos agrícolas. Intoxicação crônica e subcrônica por OTA em frangos que ingerem ração contaminada, levam à danos à saúde devido aos seus efeitos hepatotóxicos, nefrotóxicos, citotóxicos, imunotóxicos, gastrotóxicos e possivelmente carcinogênicos. Como há poucos dados sobre intoxicação aguda, o presente estudo avaliou os efeitos de uma dose única de intoxicação aguda por OTA sobre parâmetros imunológicos e hematológicos em pintainhos. Foram utilizados 16 pintainhos de um dia de idade, separados em dois grupos (n=8). Uma dose única de OTA (1400 µg kg-1 de peso corporal) foi administrada, via gavagem, para o grupo OTA e uma dose de PBS estéril para o grupo controle. No 13º dia foram coletadas amostras de sangue para avaliação dos parâmetros hematológicos e bioquímicos, e no 14º dia foi realizada a eutanásia e coleta de órgãos linfoides. Os animais do grupo OTA demonstraram diminuição significativa do total de leucócitos circulantes (p<0,001) com heteropenia (p<0,001) e linfopenia (p=0,023), diminuição do hematócrito (p=0,020), hemoglobina (p=0,032) e IgA plasmática (p=0,044) e aumento do nível plasmático de ácido úrico (p=0,045), em relação ao grupo controle. Além disso, os animais intoxicados com OTA apresentaram depleção de células linfóides na bolsa de Fabricius (p=0,016), mas não no timo ou baço (p>0,05), em relação ao controle. Para os demais parâmetros: proteínas totais do plasma, níveis plasmáticos de IgY e títulos de vacinas contra o Vírus da Doença de Newcastle (NDV) das matrizes, não houve diferenças significativas entre os grupos analisados (p>0,05), embora tenha havido uma tendência de piora nos animais contaminados. Em conclusão, mesmo uma intoxicação única aguda por OTA em alta dose, leva à supressão da resposta imune sistêmica, afetando também alguns parâmetros hematológicos ou bioquímicos em pintainhos.

Fatores de risco associados com a presença de infecções virais em aves domésticas na região Sul do Rio Grande do Sul, Brasil / Risk factors associated with the presence of viral diseases in domestic poultry in the Southern region of Rio Grande do Sul, Brazil

Background: The introduction of any infectious agent into an industrial or subsistence farm worries agribusiness owners in Brazilbecause it reduces product quality and increases treatment costs, although most diseases are untreatable, thus causing economic losseswith morbidity and mortality. Therefore, an epidemiological survey of viral diseases associated with poultry was developed by performing a detailed description of the risk factors that may be related to existing diseases using domestic poultry sample data recordedin the Regional Diagnostic Laboratory (LRD) of College of Veterinary Medicine of the Federal University of Pelotas (UFPel), RioGrande do Sul, Brazil, from 2000 to 2016.Materials, Methods & Results: Epidemiological and clinical-pathological data were collected and then compared with disease databy multivariate analysis using statistical EpiInfo version 6.04 and Microsoft Office Excel 2010 software. The frequencies and 95%confidence intervals (CI), association measures (odds ratio=OR and relative risk=RR), Chi-square test, and the results consideredsignificant with a value of P ≤ 0.05 were described. A total of 410 samples of domestic poultry were tested, and the results showed66 (16.1%) viral diseases. The following conditions were the most commonly found diseases in this study: Mareks disease (42.4%),Infectious bursal disease (31.8%), Avian leukosis (16.6%), Avian pox (7.5%) and Avian infectious bronchitis (1.5%). In this articlewe discuss the most frequent viral diseases: Mareks disease (DM) and Gumboro disease. It was also possible to conclude that birdswith Mareks disease presented higher odds of developing nerve, tegumentary and locomotors signs (P ≤ 0.05). As well as, morelikely to present tumoriform lesions in the liver, spleen, kidneys and heart P ≤ 0.05, as well as lesions in the proventriculus, musclelesions and in the sciatic nerve P ≤ 0.05. Laying poultry...(AU)

Fatores de risco associados com a presença de infecções virais em aves domésticas na região Sul do Rio Grande do Sul, Brasil / Risk factors associated with the presence of viral diseases in domestic poultry in the Southern region of Rio Grande do Sul, Brazil

Background: The introduction of any infectious agent into an industrial or subsistence farm worries agribusiness owners in Brazilbecause it reduces product quality and increases treatment costs, although most diseases are untreatable, thus causing economic losseswith morbidity and mortality. Therefore, an epidemiological survey of viral diseases associated with poultry was developed by performing a detailed description of the risk factors that may be related to existing diseases using domestic poultry sample data recordedin the Regional Diagnostic Laboratory (LRD) of College of Veterinary Medicine of the Federal University of Pelotas (UFPel), RioGrande do Sul, Brazil, from 2000 to 2016.Materials, Methods & Results: Epidemiological and clinical-pathological data were collected and then compared with disease databy multivariate analysis using statistical EpiInfo version 6.04 and Microsoft Office Excel 2010 software. The frequencies and 95%confidence intervals (CI), association measures (odds ratio=OR and relative risk=RR), Chi-square test, and the results consideredsignificant with a value of P ≤ 0.05 were described. A total of 410 samples of domestic poultry were tested, and the results showed66 (16.1%) viral diseases. The following conditions were the most commonly found diseases in this study: Marek’s disease (42.4%),Infectious bursal disease (31.8%), Avian leukosis (16.6%), Avian pox (7.5%) and Avian infectious bronchitis (1.5%). In this articlewe discuss the most frequent viral diseases: Marek’s disease (DM) and Gumboro disease. It was also possible to conclude that birdswith Marek’s disease presented higher odds of developing nerve, tegumentary and locomotors signs (P ≤ 0.05). As well as, morelikely to present tumoriform lesions in the liver, spleen, kidneys and heart P ≤ 0.05, as well as lesions in the proventriculus, musclelesions and in the sciatic nerve P ≤ 0.05. Laying poultry...

Histopathology and serology reaction to an immune complex infectious bursal disease vaccine (V877 strain) in SPF and commercial birds / Reação histopatológica e sorológica a uma vacina de imunocomplexo contra gumboro (cepa V877) em aves SPF e comerciais

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response.

O objetivo desse estudo foi investigar o efeito de uma nova vacina de imunocomplexo contra a doença de Gumboro sobre o sistema imune de aves SPF e comerciais. A avaliação da resposta à vacinação foi realizada por meio de exame histopatológico e sorologia. Os resultados desse estudo demonstraram que a vacina de imunocomplexo com cepa V877 contra Gumboro é muito segura mesmo em aves SPF da linhagem White Leghorn nas quais não existia a participação de imunidade materna. Em aves comerciais também foi demonstrado que a vacina de imunocomplexo com a cepa V877 atuou sinergicamente com diferentes níveis de anticorpos passivos maternais, iniciando a replicação do vírus vacinal a partir do momento que a imunidade passiva diminui, para promover uma resposta imunológica ativa.

Histopathology and serology reaction to an immune complex infectious bursal disease vaccine (V877 strain) in SPF and commercial birds / Reação histopatológica e sorológica a uma vacina de imunocomplexo contra gumboro (cepa V877) em aves SPF e comerciais

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response.(AU)

O objetivo desse estudo foi investigar o efeito de uma nova vacina de imunocomplexo contra a doença de Gumboro sobre o sistema imune de aves SPF e comerciais. A avaliação da resposta à vacinação foi realizada por meio de exame histopatológico e sorologia. Os resultados desse estudo demonstraram que a vacina de imunocomplexo com cepa V877 contra Gumboro é muito segura mesmo em aves SPF da linhagem White Leghorn nas quais não existia a participação de imunidade materna. Em aves comerciais também foi demonstrado que a vacina de imunocomplexo com a cepa V877 atuou sinergicamente com diferentes níveis de anticorpos passivos maternais, iniciando a replicação do vírus vacinal a partir do momento que a imunidade passiva diminui, para promover uma resposta imunológica ativa.(AU)

Relationship between virus replication and apoptosis events in IgM + cells from chicken spleen and bursa of Fabricius infected with Malaysia strain of very virulent infectious bursal disease virus

Background: Infection of IBDV was reported to be endemic in worldwide including Malaysia and can be spread orally thru polluted fodder and water source, thus causing economic losses especially in commercial poultry industry. The infection resulted in depletion of B lymphocytes and subsequently destruction of the bursa which leaded to immunosuppression of the bird and it was postulated that the depletion of cells in the bursa was due to induction of apoptosis. In the current study, the infection of Malaysia isolated very virulent IBDV UPM0081 on IgM bearing B lymphocytes (IgM+ cells) from chicken spleen and bursa was compared. Materials, Methods & Results: A total of sixty eggs were obtained and raised until the age of 3 weeks old. The birds were divided into two groups (n = 30), which one of them served as control while IBDV strain UPM0081 was used to infect another group of birds at the concentration of 103 ELD50. The birds were observed and sacrificed at day 2, 4 and 5 post infections. Spleen and bursa of Fabricius were harvested and subjected to IgM+ cell enrichment using microbeads. The cell viability of enriched cells was assayed using MTT and cell cycle was analyzed using propidium iodide. Annexin V FITC and acridine orange/propidium iodide double stain assays were used to determine the event of apoptosis in the enriched IgM+ cells. Also, the IBDV viral load was also [...](AU)

Relationship between virus replication and apoptosis events in IgM + cells from chicken spleen and bursa of Fabricius infected with Malaysia strain of very virulent infectious bursal disease virus

Background: Infection of IBDV was reported to be endemic in worldwide including Malaysia and can be spread orally thru polluted fodder and water source, thus causing economic losses especially in commercial poultry industry. The infection resulted in depletion of B lymphocytes and subsequently destruction of the bursa which leaded to immunosuppression of the bird and it was postulated that the depletion of cells in the bursa was due to induction of apoptosis. In the current study, the infection of Malaysia isolated very virulent IBDV UPM0081 on IgM bearing B lymphocytes (IgM+ cells) from chicken spleen and bursa was compared. Materials, Methods & Results: A total of sixty eggs were obtained and raised until the age of 3 weeks old. The birds were divided into two groups (n = 30), which one of them served as control while IBDV strain UPM0081 was used to infect another group of birds at the concentration of 103 ELD50. The birds were observed and sacrificed at day 2, 4 and 5 post infections. Spleen and bursa of Fabricius were harvested and subjected to IgM+ cell enrichment using microbeads. The cell viability of enriched cells was assayed using MTT and cell cycle was analyzed using propidium iodide. Annexin V FITC and acridine orange/propidium iodide double stain assays were used to determine the event of apoptosis in the enriched IgM+ cells. Also, the IBDV viral load was also [...]

Ação trófica de aditivos fitogênicos, glutamina e ácido glutâmico sobre a Bursa de Fabrícius e intestino delgado de frangos de corte / Trophic action of phytogenic additives, glutamine and glutamic acid on Bursa Fabricii and small intestine of broilers

The aim of this study was to evaluate the effect of phytogenic additives and glutamine plus glutamic acid, associated or not, on histomorphometry of bursa of Fabricius and small intestine, oocyst count and lesion scores, and carbon turnover of duodenal mucosa of broiler chickens infected with Eimeria acervulina. A total of 450 male broiler chickens was distributed into a completely randomized design with six treatments and three replications. Treatments consisted of control diet (CD); CD + coccidiosis vaccine; CD + antibiotic performance enhancers and anticoccidial (APE/AC); CD + glutamine and glutamic acid (Gln/Glu); CD + phytogenic additives (PA); CD + Gln/Glu + PA. Birds on treatment CD + vaccine were vaccinated via drinking water at three days of age against coccidiosis. At 16 days of age all birds of all treatments were inoculated orally and individually with 500,000 oocysts of Eimeria acervulina. There was no treatment effect on lesion score in the intestinal epithelium of birds. The smaller number of excreted oocysts was observed in groups of birds fed diets containing APE/AC and PA. Were observed better results of villus height and crypt depth for duodenum and ileum of birds of treatments containing Gln/Glu at 7 days of age, and Gln/Glu and PA at 21 days of age. Higher percentage of cortical area from bursa follicles was observed in birds fed diets supplemented with Gln/Glu and PA at 7, 14 and 21 days of age. Increased turnover of intestinal mucosa was observed in treatments containing Gln/Glu, indicating acceleration in development and regeneration of damaged tissue. Glutamine plus glutamic acid and phytogenic additives can provide improvements to structure, and thus to intestinal function, as well as to better immune response against the infectious challenges. Phytogenic additives can be used for coccidiosis control of broiler chickens where the use of antibiotic performance enhancers and anticoccidials is prohibited.(AU)

O objetivo deste trabalho foi avaliar o efeito dos aditivos fitogênicos e da glutamina mais ácido glutâmico, associados ou não, sobre a histomorfometria da Bursa de Fabricius e intestino delgado, sobre contagem de oocistos e escores de lesão e sobre o turnover do carbono da mucosa intestinal de frangos de corte experimentalmente infectadas com Eimeria acervulina. Para isso foram utilizados 450 pintos de corte machos distribuídos em delineamento inteiramente casualisado, com seis tratamentos e três repetições. Os tratamentos consistiram de dieta controle (DC); DC + Vacina de coccidiose; DC + antibióticos melhoradores de desempenho e anticoccidiano (AMD/AC); DC + glutamina e ácido glutâmico (Gln/Glu); DC + sditivos fitogênicos (AFs); DC + Gln/Glu + AFs. As aves do tratamento DC + Vacina foram vacinadas via água de bebida, aos três dias de idade, contra coccidiose. Aos 16 dias de idade todas as aves de todos os tratamentos foram inoculadas oralmente e individualmente com 500.000 oocistos de Eimeria acervulina. Não houve efeito dos tratamentos para escore de lesão no epitélio intestinal das aves. O menor número de oocistos excretados foi observado nos grupos de aves alimentadas com dieta contendo AMD/AC e AFs. Foram observados melhores resultados para altura das vilosidades e profundidade das criptas do duodeno e ílio das aves dos tratamentos contendo Gln/Glu, aos 7 dias de idade e Gln/Glu e AFs aos 21 dias de idade. Maior porcentagem de área cortical dos folículos bursais foi observada em aves alimentadas com dieta suplementada com Gln/Glu e AFs aos 7, 14 e 21 dias de idade. Maior turnover da mucosa intestinal foi observada em aves dos tratamentos contendo Gln/Glu, indicando aceleração do desenvolvimento e regeneração do tecido lesado. Glutamina mais ácido glutâmico e aditivos fitogênicos podem oferecer melhorias à estrutura e, consequentemente, à função do intestino, bem como melhores condições para resposta imune frente à desafios infecciosos...(AU)

Doença infecciosa bursal

A doença infecciosa bursal (DIB),também conhecida como doença de Gumboro, em referência à cidade dos Estados Unidos (no estado de Delaware) onde foi descrita pela primeira vez, é uma das principais doenças a comprometer a imuno competência em aves. A doença atinge principalmente abolsa cloacal (BC), outro nome para a bolsa de Fabricius, destruindo oslinfoblastos B, precursores dos plasmócitos,estes responsáveis pela síntese de anticorpos.A doença é importante pela alta morbidade, alta a moderada mortalidade,imunodepressão por perda na diversidade de linhagens de linfócitos B e redução da viabilidade das aves industriais, com aumento da condenação por oportunismo infeccioso. A DIB está em muitos casos naturais, em infecção associada à anemia infecciosa das galinhas, causada por um circovírus que atinge linfócitos T(timo). As coinfecções,inclusive com outros vírus, como adenovírus e reovírus, e bactérias,como Escherichia coli e Clostridium, resultam em maior comprometimento das funções sistêmicas e do sistema imune, com maior morbidade,maior mortalidade e maior perda da imunocompetência.

Doença infecciosa bursal

A doença infecciosa bursal (DIB),também conhecida como doença de Gumboro, em referência à cidade dos Estados Unidos (no estado de Delaware) onde foi descrita pela primeira vez, é uma das principais doenças a comprometer a imuno competência em aves. A doença atinge principalmente abolsa cloacal (BC), outro nome para a bolsa de Fabricius, destruindo oslinfoblastos B, precursores dos plasmócitos,estes responsáveis pela síntese de anticorpos.A doença é importante pela alta morbidade, alta a moderada mortalidade,imunodepressão por perda na diversidade de linhagens de linfócitos B e redução da viabilidade das aves industriais, com aumento da condenação por oportunismo infeccioso. A DIB está em muitos casos naturais, em infecção associada à anemia infecciosa das galinhas, causada por um circovírus que atinge linfócitos T(timo). As coinfecções,inclusive com outros vírus, como adenovírus e reovírus, e bactérias,como Escherichia coli e Clostridium, resultam em maior comprometimento das funções sistêmicas e do sistema imune, com maior morbidade,maior mortalidade e maior perda da imunocompetência.

Evaluation of bursal lymphoid depletion: comparison between the conventional histology method and digital lymphocyte depletion evaluation system / Avaliação da depleção linfóide bursal: comparação entre a histologia convencional e o sistema de avaliação digital da depleção linfocitária

Fifty-five bursa of Fabricius (BF) were evaluated by optical microscopy for three different avian histopathologists (H1, H3 and H4) to determine the degree of lymphoid depletion. One histologist evaluated the same slides at two different times (H1 and H2) with four-months interval between the observations. The same BFs were evaluated using the system of Digital Lymphocyte Depletion Evaluation (ADDL), being performed by three differents operators of the system, not histopathologists. The results showed was a significant difference between the histopathologists and between the scores established by the same expert (H1 and H2). However, there were not significant differences between the scores with the ADDL system, obtained using ADDL. The results make clear the fragility of the subjective lymphocyte depletion score classification by the traditional histologic method, while the ADDL system proves to be more appropriated for the assessment of the lymphoid loss in the BF.(AU)

Cinquenta e cinco bursas de Fabricius (BF) foram avaliadas através da microscopia óptica por três diferentes histopatologistas aviários (H1, H3 e H4) para determinar o grau de depleção linfóide. Um histopatologista avaliou as amostras em dois momentos distintos (H1 e H2) com quatro meses de intervalo entre as observações. As mesmas BF foram avaliadas utilizando-se o sistema de Avaliação Digital da Depleção Linfocitária (ADDL), sendo realizadas por três diferentes operadores do sistema, não histopatologistas. Os resultados mostraram diferenças significativas entre os histopatologistas e entre um mesmo histopatologista (H1 e H2). Contudo, não houve diferenças significativas entre os escores obtidos utilizando-se ADDL. Estes resultados caracterizam a fragilidade da classificação subjetiva em escores de depleção linfóide, enquanto o sistema ADDL prova ser um sistema robusto de avaliação da perda linfocitária na BF.(AU)

Immune response elicited by the oral administration of an intermediate strain of IBDV in chickens

The immune response elicited by the oral inoculation of an intermediate strain of infectious bursal disease virus was studied in chickens. A strong over expression of IL-6, IL-8, IFNα and IFNγ was observed in bursa at 3 days post inoculation together with an increase in splenic NO2 release. An influx of T-lymphocytes was also detected.

Canarypox virus expressing infectious bursal disease VP2 protein as immunogen for chickens

Canarypox viruses (CNPV) carrying the coding sequence of VP2 protein from infectious bursal disease virus (IBDV) were obtained. These viruses were able to express VP2 protein in vitro and to induce IBDV-neutralizing antibodies when inoculated in specific pathogen-free chickens demonstrating that CNPV platform is usefulness to develop immunogens for chickens.

Canarypox virus expressing infectious bursal disease VP2 protein as immunogen for chickens

Canarypox viruses (CNPV) carrying the coding sequence of VP2 protein from infectious bursal disease virus (IBDV) were obtained. These viruses were able to express VP2 protein in vitro and to induce IBDV-neutralizing antibodies when inoculated in specific pathogen-free chickens demonstrating that CNPV platform is usefulness to develop immunogens for chickens.(AU)

Efficient assembly of full-length infectious clone of Brazilian IBDV isolate by homologous recombination in yeast

The Infectious Bursal Disease Virus (IBDV) causes immunosuppression in young chickens. Advances in molecular virology and vaccines for IBDV have been achieved by viral reverse genetics (VRG). VRG for IBDV has undergone changes over time, however all strategies used to generate particles of IBDV involves multiple rounds of amplification and need of in vitro ligation and restriction sites. The aim of this research was to build the world's first VRG for IBDV by yeast-based homologous recombination; a more efficient, robust and simple process than cloning by in vitro ligation. The wild type IBDV (Wt-IBDV-Br) was isolated in Brazil and had its genome cloned in pJG-CMV-HDR vector by yeast-based homologous recombination. The clones were transfected into chicken embryo fibroblasts and the recovered virus (IC-IBDV-Br) showed genetic stability and similar phenotype to Wt-IBDV-Br, which were observed by nucleotide sequence, focus size/morphology and replication kinetics, respectively. Thus, IBDV reverse genetics by yeast-based homologous recombination provides tools to IBDV understanding and vaccines/viral vectors development.

Desempenho e resposta imune de frangos de corte alimentados com dietas suplementadas com cromo na forma orgânica / Immune response and performance by broiler chickens dietarysupplemented with chromium in organic form

O experimento foi conduzido com o objetivo de avaliar o efeito da suplementação de cromo-orgânico, sobre o desempenho, biometria dos órgãos digestivos e linfoides, histomoformetria da bolsa cloacal e rendimento de carcaça e cortes nobres de frangos de corte de 1 a 41 dias de idade, naturalmente submetidos a estresse por calor cíclico. Foram utilizados 400 pintos de corte da linhagem Cobb, em um delineamento experimental inteiramente casualizado, com cinco tratamentos: 0; 350; 700; 1050 e 1400 ppb de cromo na ração. Os valores do índice de temperatura de globo e umidade foram respectivamente, 83,39 e 80, para fase de crescimento e terminação. A suplementação do cromo orgânico influenciou (P 0,01) de forma quadrática a conversão alimentar dos animais segundo a equação Y=1,67-0,00016x+0,00000012x² (r² 0,976), na fase de 1 a 21 dias de idade. Os níveis de suplementação do cromo orgânico proporcionaram melhor índice de eficiência produtiva e maior percentual de parênquima cortical nas aves aos 21 dias. Na fase de 1 a 41 dias de idade, verificou-se que o peso de penas foi influenciado positivamente com os níveis de cromo orgânico e que não houve efeito para o desempenho dos frangos. Conclui-se que a suplementação da ração com cromo orgânico melhora desempenho e a resposta imune de frangos de corte frente a condições de estresse por calor.(AU)

This study was conducted to evaluate the effect of adding organic chromium dietary supplementation on performance, digestiveand lymphoid organs biometry and histomorphometry of the clocal bursa and on carcass and prime cuts performance of broilersfrom 1 to 41 days old, naturally stressed by heat cyclic. We used 400 chicks Cobb, the experimental design adopted was acompletely randomized, with five treatments: 0; 350; 700; 1050 and 1400 ppb chromium in diet. The supplementation withorganic chromium influenced (p<0,01) quadratic form on alimentary conversion the animals according to the equation Y = 1.67to 0.00016 x 0.00000012 x ² (r ² 0.976) in the period 1 to 21. The levels of supplementation of organic chromium improvementproductive efficiency and percentage of cortical parenchyma of broilers to 21 days. In phase to 1 from 41 days old, it was observedimprovement the feathers weight with levels of organic chromium, and there wasnt influence on performance of broilers. Thechromium in the organic form improves the performance of broiler chickens and immune response by broiler chickens in cyclic heat stress.(AU)

Desempenho e resposta imune de frangos de corte alimentados com dietas suplementadas com cromo na forma orgânica / Immune response and performance by broiler chickens dietarysupplemented with chromium in organic form

O experimento foi conduzido com o objetivo de avaliar o efeito da suplementação de cromo-orgânico, sobre o desempenho, biometria dos órgãos digestivos e linfoides, histomoformetria da bolsa cloacal e rendimento de carcaça e cortes nobres de frangos de corte de 1 a 41 dias de idade, naturalmente submetidos a estresse por calor cíclico. Foram utilizados 400 pintos de corte da linhagem Cobb, em um delineamento experimental inteiramente casualizado, com cinco tratamentos: 0; 350; 700; 1050 e 1400 ppb de cromo na ração. Os valores do índice de temperatura de globo e umidade foram respectivamente, 83,39 e 80, para fase de crescimento e terminação. A suplementação do cromo orgânico influenciou (P 0,01) de forma quadrática a conversão alimentar dos animais segundo a equação Y=1,67-0,00016x+0,00000012x² (r² 0,976), na fase de 1 a 21 dias de idade. Os níveis de suplementação do cromo orgânico proporcionaram melhor índice de eficiência produtiva e maior percentual de parênquima cortical nas aves aos 21 dias. Na fase de 1 a 41 dias de idade, verificou-se que o peso de penas foi influenciado positivamente com os níveis de cromo orgânico e que não houve efeito para o desempenho dos frangos. Conclui-se que a suplementação da ração com cromo orgânico melhora desempenho e a resposta imune de frangos de corte frente a condições de estresse por calor.

This study was conducted to evaluate the effect of adding organic chromium dietary supplementation on performance, digestiveand lymphoid organs biometry and histomorphometry of the clocal bursa and on carcass and prime cuts performance of broilersfrom 1 to 41 days old, naturally stressed by heat cyclic. We used 400 chicks Cobb, the experimental design adopted was acompletely randomized, with five treatments: 0; 350; 700; 1050 and 1400 ppb chromium in diet. The supplementation withorganic chromium influenced (p<0,01) quadratic form on alimentary conversion the animals according to the equation Y = 1.67to 0.00016 x 0.00000012 x ² (r ² 0.976) in the period 1 to 21. The levels of supplementation of organic chromium improvementproductive efficiency and percentage of cortical parenchyma of broilers to 21 days. In phase to 1 from 41 days old, it was observedimprovement the feathers weight with levels of organic chromium, and there wasn’t influence on performance of broilers. Thechromium in the organic form improves the performance of broiler chickens and immune response by broiler chickens in cyclic heat stress.

Immunomodulatory and growth-promoting effect of a probiotic supplemented in the feed of broiler chicks vaccinated against infectious bursal disease

This study was designed to investigate the effects of a probiotic plus an immunomodulatory product on the growth performance, immune response and net economic returns of broiler chicks vaccinated against Infectious bursal diseases virus (IBDV). A flock of 350 day-old chicks were equally and randomly distributed in seven groups, each comprising 50 birds. A mixture of microorganisms (¹Probiotic) or Cyclophosphamide (immune suppressor) was offered through feed supplementation to different groups. The Probiotic, consisting of Lactobacillus species, Bifidobacterium, Streptococcus salivarius and Enterococcus faecium, in addition to Aspergillus oryza and Candida pintolopessii. Compared with control treatment group, the probiotic-supplemented chicks had better feed conversion ratio (FCR) (1.938 and 1.959), with significantly heavier live body weight 2141.0±34.2 and 2120.3±33.2, respectively. Similarly, their antibody titers against IBDV were significantly higher (941 and 832) on day 35. No morbidity and mortality were observed in these groups. This study suggests that a product composed of a probiotic and cyclophosphamide enhanced the growth rate as well as the immunity against infectious bursal disease virus of broilers chicks.(AU)

Evaluation of follicular lymphoid depletion in the Bursa of Fabricius: an alternative methodology using digital image analysis and artificial neural networks / Avaliação da depleção linfóide folicular da Bursa de Fabricius: uma metodologia alternativa utilizando análise digital de imagem e redes neurais artificiais

Fifty Bursa of Fabricius (BF) were examined by conventional optical microscopy and digital images were acquired and processed using Matlab® 6.5 software. The Artificial Neuronal Network (ANN) was generated using Neuroshell® Classifier software and the optical and digital data were compared. The ANN was able to make a comparable classification of digital and optical scores. The use of ANN was able to classify correctly the majority of the follicles, reaching sensibility and specificity of 89 percent and 96 percent, respectively. When the follicles were scored and grouped in a binary fashion the sensibility increased to 90 percent and obtained the maximum value for the specificity of 92 percent. These results demonstrate that the use of digital image analysis and ANN is a useful tool for the pathological classification of the BF lymphoid depletion. In addition it provides objective results that allow measuring the dimension of the error in the diagnosis and classification therefore making comparison between databases feasible.(AU)

Cinquenta Bursa de Fabrícius (BF) foram examinadas através de microscopia óptica convencional e imagens digitais foram obtidas e processadas através do software Matlab® 6.5. Redes Neurais Artificiais (ANN) foram geradas com a utilização do software Neuroshell® Classifier, e os dados das análises óptica e digital foram comparados. A ANN classificou corretamente a maioria dos folículos, atingindo sensibilidade e especificidade de 89 por cento e 96 por cento, respectivamente. Quando os folículos foram agrupados de forma binária houve um aumento da sensibilidade para 90 por cento e obteve-se um valor máximo para a especificidade de 92 por cento. Estes resultados demonstram que o uso da análise digital de imagem associada à ANNé uma ferramenta bastante útil para a classificação patológica da depleção linfóide da BF. Além disso, fornece resultados objetivos que permitem medir a dimensão do erro classificatório, tornando possível a comparação entre distintos bancos de dados.(AU)

Apoptosis detection in embryonic chicken lymphoid tissues infected with attenuated very virulent infectious bursal disease virus (vvIBDV)

We exposed chicken embryos at embryonating day (ED18) to a cell-adapted very virulent strain of IBDV (ca-vvIBDV) and original vvIBDV and examined the apoptosis from infected bursa of Fabricius (BF) and thymus organs. Following ca-vvIBDV exposure, embryonic bursa showed mild cellular destruction, lower rate of apoptosis and presence of viral proteins detectable by immunohistochemistry. In contrary, original vvIBDV exposed embryos had an enhanced detectable changes in the bursa associated to an increase apoptotic events, and most of the times, total destruction of BF follicles. In thymus, viral antigen was detectable until after hatch. Positives cell signals to activated caspase-3 were intensively detect in embryos lymphoid tissues exposed to original vvIBDV observed in BF and less in thymus. No immunoreactive thymocytes were visualized in embryos exposed to ca-vvIBDV. Apoptosis changes, such as chromatin condensation, DNA fragmentation, and the appearance of apoptotic nuclear bodies, were observed in both organs. TUNEL-detected DNA was more intense in original vvIBDV infected lymphoid cells, and less apoptotic cells were detectable in attenuated strain. By sequencing analysis, e attenuation presented amino acid changes at position 222 (A→→P), 256 (I→V) and 279 (D→N). One serine in the serine-rich heptapeptide (position 333) was substituted into other amino acid which is similar to the IBDV vaccine strain. Taken together our results indicate that virus attenuation interferes with caspase-3 apoptotic pathway and may play an important role in switch viral pathogenesis.