Phylogenetic and pathotypic characterization of a Newcastle disease virus strain isolated from ducks and pigeons in Hubei, China

Newcastle disease is a highly contagious disease responsible for major outbreaks and considerable economic losses in the poultry industry in China. There is still little information available regarding gene characterization of the NDV, especially in ducks and pigeons. Therefore, the aim of this study was to investigate NDV isolated from ducks and pigeons in Hubei, China. In this study, three NDVs from ducks and pigeons were isolated between 2013 and 2015.The fusion protein (F) gene of the NDV isolates was sequenced and phylogenetically analyzed. The clinical signs and gross histopathological lesions were examined. Phylogenetic analysis of these strains indicated that all the sequences are classified as genotype II. The isolates shared a 112 G-R-Q-G-R-L 117motif at the F protein cleavage site, indicating that these three isolates strains are lentogenic. Necropsy and histopathology showed the typical pathological changes. It was concluded that commercial ducks and pigeons in Hubei province carry lentogenic NDV strains with regular genetic divergence, indicating that these species may act as the main reservoirs of NDV in poultry. Therefore, strategies and surveillance should be undertaken to reduce the risk of ND outbreaks.(AU)

Phylogenetic and pathotypic characterization of a Newcastle disease virus strain isolated from ducks and pigeons in Hubei, China

Newcastle disease is a highly contagious disease responsible for major outbreaks and considerable economic losses in the poultry industry in China. There is still little information available regarding gene characterization of the NDV, especially in ducks and pigeons. Therefore, the aim of this study was to investigate NDV isolated from ducks and pigeons in Hubei, China. In this study, three NDVs from ducks and pigeons were isolated between 2013 and 2015.The fusion protein (F) gene of the NDV isolates was sequenced and phylogenetically analyzed. The clinical signs and gross histopathological lesions were examined. Phylogenetic analysis of these strains indicated that all the sequences are classified as genotype II. The isolates shared a 112 G-R-Q-G-R-L 117motif at the F protein cleavage site, indicating that these three isolates strains are lentogenic. Necropsy and histopathology showed the typical pathological changes. It was concluded that commercial ducks and pigeons in Hubei province carry lentogenic NDV strains with regular genetic divergence, indicating that these species may act as the main reservoirs of NDV in poultry. Therefore, strategies and surveillance should be undertaken to reduce the risk of ND outbreaks.

Renal Dose Dopamine Mediates the Level of Aquaporin-2 Water Channel (Aqp2) in Broiler Chickens

ABSTRACT Aquaporin 2 (AQP2) is a small protein located in the collecting tubules of kidneys; it plays an important role in the concentration and production of urine. The aim of this study was to determine the expression level of the AQP2 gene in the kidney of broiler chickens after the administration of renal­dose dopamine. Broiler chickens (25 days-old) were randomly divided into two groups (n=20 per group): intravenous administration of saline solution (control group) or renal-dose dopamine (dopamine group). The expression and localization of the AQP2 gene were evaluated by real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC), respectively. The protein level of AQP2 was analyzed by western blot analysis. The dopamine group presented no significant difference (p>0.05) in the biochemical criterion or mRNA expression of AQP2 compared with the control group. However, AQP2 protein level was significantly reduced (p 0.05) in the membrane of renal tubular epithelial cells. In contrast, protein level was significantly increased (p 0.05) in the cytoplasm of the dopamine group compared with the control group. Moreover, AQP2 protein was apparently more distributed and localized in the cytoplasmic vacuoles than in the membranes of the kidney in the renal­dose dopamine administered chickens group. In conclusion, present findings suggest that renal­dose dopamine mediates the level of AQP2 protein via shuttle from the cell membrane to the cytoplasm rather than changing the expression of AQP2 gene to adjust the secretion and absorption of water in kidney.(AU)

Renal Dose Dopamine Mediates the Level of Aquaporin-2 Water Channel (Aqp2) in Broiler Chickens

ABSTRACT Aquaporin 2 (AQP2) is a small protein located in the collecting tubules of kidneys; it plays an important role in the concentration and production of urine. The aim of this study was to determine the expression level of the AQP2 gene in the kidney of broiler chickens after the administration of renal­dose dopamine. Broiler chickens (25 days-old) were randomly divided into two groups (n=20 per group): intravenous administration of saline solution (control group) or renal-dose dopamine (dopamine group). The expression and localization of the AQP2 gene were evaluated by real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC), respectively. The protein level of AQP2 was analyzed by western blot analysis. The dopamine group presented no significant difference (p>0.05) in the biochemical criterion or mRNA expression of AQP2 compared with the control group. However, AQP2 protein level was significantly reduced (p 0.05) in the membrane of renal tubular epithelial cells. In contrast, protein level was significantly increased (p 0.05) in the cytoplasm of the dopamine group compared with the control group. Moreover, AQP2 protein was apparently more distributed and localized in the cytoplasmic vacuoles than in the membranes of the kidney in the renal­dose dopamine administered chickens group. In conclusion, present findings suggest that renal­dose dopamine mediates the level of AQP2 protein via shuttle from the cell membrane to the cytoplasm rather than changing the expression of AQP2 gene to adjust the secretion and absorption of water in kidney.

In vivo analysis the effect of antibiotic growth promoters (AGPs), Oxytetracycline di-hydrate and Tylosin phosphate on the intestinal microflora in broiler chicken / Análise in vivo do efeito de antibióticos promotores de crescimento (AGPs), di-hidrato de oxitetraciclina e fosfato de tilosina na microflora intestinal em frangos de corte

The study was aimed to analyse the effects of antibiotic growth promoters (AGPs), Oxytetracycline di-hydrate and Tylosin phosphate on the intestinal microflora in broiler chicken. The AGPs were provided in different concentrations solely or in combinations for 42 days of rearing. Faecal samples were collected from the intestine (duodenum, jejunum and caeca) of broiler chicken on 14th, 28th and 42nd days of trial. Samples were cultured on different selective medium and bacterial identification was performed by different biochemical and molecular diagnostic tools. Results showed a significant effect of AGPs on the growth of pathogenic microorganisms such as Escherichia coli and Clostridium perfringens in the intestine. Interestingly, an impaired growth was observed for both bacterium showing a significant effect (P<0.05) of AGPs on E. coli and C. perfringens on day 14th, 28th, and 42nd. This effect was observed solely and in combination while using AGPs. Data further showed that the effect was more prominent in combination and with an increase concentration of AGPs. Remarkably, no impairment was seen on the growth of L. reuteri at different sites of intestine and duration (14th, 28th, and 42nd days). The results showed that the use of AGPs in diet has no harmful effect on beneficial bacteria, however, an impaired growth was seen on the harmful bacteria. It is suggested that a combination of AGPs (OXY-1.0+TP-0.5) is economical and have no harmful effect on the broiler chicken. The use of AGPs in a recommended dose and for a specific period of time are safe to use in poultry both as growth promoter and for the prevention of diseases.

O estudo teve como objetivo analisar os efeitos dos antibióticos promotores de crescimento (AGPs), di-hidrato de oxitetraciclina e fosfato de tilosina na microflora intestinal de frangos de corte. Os AGPs foram fornecidos em diferentes concentrações isoladamente ou em combinações por 42 dias de criação. Amostras fecais foram coletadas do intestino (duodeno, jejuno e ceco) de frangos de corte no 14º, 28º e 42º dias de ensaio. As amostras foram cultivadas em diferentes meios seletivos e a identificação bacteriana foi realizada por diferentes ferramentas de diagnóstico bioquímico e molecular. Os resultados mostraram um efeito significativo dos AGPs no crescimento de microrganismos patogênicos como Escherichia coli e Clostridium perfringens no intestino. Curiosamente, um crescimento prejudicado foi observado para ambas as bactérias, mostrando um efeito significativo (P <0,05) de AGPs em E. coli e C. perfringens nos dias 14, 28 e 42. Este efeito foi observado apenas e em combinação com o uso de AGPs. Os dados mostraram ainda que o efeito foi mais proeminente em combinação e com um aumento da concentração de AGPs. Nenhum comprometimento foi observado no crescimento de L. reuteri em diferentes locais do intestino e duração (14º, 28º e 42º dias). Os resultados mostraram que o uso de AGPs na dieta não tem efeito nocivo nas bactérias benéficas, no entanto, foi observado um crescimento prejudicado nas bactérias nocivas. Sugere-se que uma combinação de AGPs (OXY-1.0+TP-0.5) seja econômica e não tenha efeito prejudicial sobre o frango de corte. O uso de AGPs em uma dose recomendada e por um período de tempo específico é seguro para uso em aves tanto como promotor de crescimento quanto para prevenção de doenças.