Accuracy of quantitative polymerase chain reaction in samples of frozen and paraffin-embedded healthy skin for the diagnosis of canine visceral leishmaniasis / Acurácia da reação em cadeia da polimerase quantitativa em amostras de pele íntegra congelada e parafinada no diagnóstico da leishmaniose visceral canina

The purpose of the present work was to evaluate the accuracy of quantitative polymerase chain reaction (qPCR) performed on samples of fresh frozen tissue (FT) and formalin-fixed, paraffin-embedded (FFPE) healthy skin. This is a validation study conducted with samples from 46 dogs from an endemic area in Brazil. After sample collection, DNA extractions were conducted using commercial kits and qPCR was oriented to kinetoplast DNA (kDNA) targets of the Leishmania infantum species. The results obtained for the FFPE samples showed 63.6% sensitivity and 77.1% specificity, whereas those obtained for the FT samples showed 100% and 48.6%, respectively. Poor agreement was observed for the results of the qPCR technique with FT and FFPE samples. Our results suggest freezing as the most suitable conservation method for the formation of sample databases considering DNA recovery.(AU)

O objetivo deste trabalho foi avaliar a acurácia da PCR quantitativa (qPCR) realizada em amostras de pele íntegra congelada (FT) e parafinada (FFPE). Trata-se de um estudo de validação, com amostras provenientes de 46 cães de uma área endêmica no Brasil. Após as coletas de amostras, as extrações de DNA foram realizadas utilizando-se kits comerciais, e a qPCR foi orientada para alvos do kDNA da espécie Leishmania infantum. Os resultados obtidos para as amostras FFPE foram 63,6% de sensibilidade e 77,1% de especificidade; para as amostras FT, 100% e 48,6%, respectivamente. A concordância dos resultados da técnica de qPCR com amostras FT e FFPE foi pobre. Os resultados sugerem que o congelamento é o método mais adequado de conservação para banco de amostras para recuperação de DNA.(AU)

Accuracy of quantitative polymerase chain reaction in samples of frozen and paraffin-embedded healthy skin for the diagnosis of canine visceral leishmaniasis

ABSTRACT The purpose of the present work was to evaluate the accuracy of quantitative polymerase chain reaction (qPCR) performed on samples of fresh frozen tissue (FT) and formalin-fixed, paraffin-embedded (FFPE) healthy skin. This is a validation study conducted with samples from 46 dogs from an endemic area in Brazil. After sample collection, DNA extractions were conducted using commercial kits and qPCR was oriented to kinetoplast DNA (kDNA) targets of the Leishmania infantum species. The results obtained for the FFPE samples showed 63.6% sensitivity and 77.1% specificity, whereas those obtained for the FT samples showed 100% and 48.6%, respectively. Poor agreement was observed for the results of the qPCR technique with FT and FFPE samples. Our results suggest freezing as the most suitable conservation method for the formation of sample databases considering DNA recovery

RESUMO O objetivo deste trabalho foi avaliar a acurácia da PCR quantitativa (qPCR) realizada em amostras de pele íntegra congelada (FT) e parafinada (FFPE). Trata-se de um estudo de validação, com amostras provenientes de 46 cães de uma área endêmica no Brasil. Após as coletas de amostras, as extrações de DNA foram realizadas utilizando-se kits comerciais, e a qPCR foi orientada para alvos do kDNA da espécie Leishmania infantum. Os resultados obtidos para as amostras FFPE foram 63,6% de sensibilidade e 77,1% de especificidade; para as amostras FT, 100% e 48,6%, respectivamente. A concordância dos resultados da técnica de qPCR com amostras FT e FFPE foi pobre. Os resultados sugerem que o congelamento é o método mais adequado de conservação para banco de amostras para recuperação de DNA.

Accuracy of quantitative polymerase chain reaction in samples of frozen and paraffin-embedded healthy skin for the diagnosis of canine visceral leishmaniasis / Acurácia da reação em cadeia da polimerase quantitativa em amostras de pele íntegra congelada e parafinada no diagnóstico da leishmaniose visceral canina

The purpose of the present work was to evaluate the accuracy of quantitative polymerase chain reaction (qPCR) performed on samples of fresh frozen tissue (FT) and formalin-fixed, paraffin-embedded (FFPE) healthy skin. This is a validation study conducted with samples from 46 dogs from an endemic area in Brazil. After sample collection, DNA extractions were conducted using commercial kits and qPCR was oriented to kinetoplast DNA (kDNA) targets of the Leishmania infantum species. The results obtained for the FFPE samples showed 63.6% sensitivity and 77.1% specificity, whereas those obtained for the FT samples showed 100% and 48.6%, respectively. Poor agreement was observed for the results of the qPCR technique with FT and FFPE samples. Our results suggest freezing as the most suitable conservation method for the formation of sample databases considering DNA recovery.(AU)

O objetivo deste trabalho foi avaliar a acurácia da PCR quantitativa (qPCR) realizada em amostras de pele íntegra congelada (FT) e parafinada (FFPE). Trata-se de um estudo de validação, com amostras provenientes de 46 cães de uma área endêmica no Brasil. Após as coletas de amostras, as extrações de DNA foram realizadas utilizando-se kits comerciais, e a qPCR foi orientada para alvos do kDNA da espécie Leishmania infantum. Os resultados obtidos para as amostras FFPE foram 63,6% de sensibilidade e 77,1% de especificidade; para as amostras FT, 100% e 48,6%, respectivamente. A concordância dos resultados da técnica de qPCR com amostras FT e FFPE foi pobre. Os resultados sugerem que o congelamento é o método mais adequado de conservação para banco de amostras para recuperação de DNA.(AU)

FEEDING PROGRAM FOR LAYING HENS BASED ON PROTEIN MODELS. / PROGRAMAS DE ALIMENTAÇÃO PARA POEDEIRAS BASEADO EM MODELO PARA PREDIÇÃO DAS EXIGÊNCIAS DE PROTEÍNA.

The objective of this study was to evaluate feeding programs based on protein requirement model compared to the recommendation to Lohmann. One-hundred-forty-four 35-week-old Lohmann LSL laying hens were distributed on a randomized design with 3 treatments and 6 replications of 8 laying hens. We tested the following feeding programs: 1- ad libitum feeding according to the Lohmann recommendation; 2- Controlled feeding according to the Lohmann recommendation; 3- Feeding according to Basaglia (1999) model: CP = 1,94.W0,75 + 0,48.G + 0,301.E, where W is the body weight (kg), T is the ambient temperature (0C), G is the daily weight gain (grams), and E is the daily egg mass (grams). The body weight, egg production, and egg weight of laying hens fed in accordance with protein model were different from groups fed according to the recommendation to Lohmann. However, the birds fed in accordance with the model ingested more protein in comparison to the recommendation to Lohmann and presented a better feed conversion than the groups fed ad libitum. KEY -WORDS: Laying hens. Feeding program. Crude protein requirements.