Limits...
Quantity of virulent fowl adenovirus serotype 1 correlates with clinical signs, macroscopical and pathohistological lesions in gizzards following experimental induction of gizzard erosion in broilers.

Grafl B, Liebhart D, Günes A, Wernsdorf P, Aigner F, Bachmeier J, Hess M - Vet. Res. (2013)

Bottom Line: Clinically, both infected groups showed significant decrease of weight compared to respective negative control groups.Tissue samples were investigated by a recently developed real-time PCR and the viral DNA load was calculated from gizzard, liver, spleen and cloacal swabs with the highest amounts of FAdV-1 DNA found in the gizzard.For the first time, successful reproduction of clinical signs in broilers as well as pathological lesions in the gizzard were achieved with a European FAdV-1 isolate displaying some genetic differences to so far reported virulent FAdV-1 from Japan.

View Article: PubMed Central - HTML - PubMed

ABSTRACT
In the present study day-old specific-pathogen-free (SPF) and commercial broilers with maternally derived fowl adenovirus serotype 1 (FAdV-1) antibodies were orally infected with a European "pathogenic" FAdV-1, isolated from broilers showing signs of gizzard erosion. During the experiment, broilers were observed and weighed daily up to 17 days post infection (dpi). Clinically, both infected groups showed significant decrease of weight compared to respective negative control groups. Birds were examined by necropsy at 3, 7, 10, 14 and 17 dpi. Pathological changes in the gizzards were noticed in both experimentally infected groups from 7 dpi onwards. Macroscopically, erosion of the koilin layer and inflammation or ulceration of the gizzard mucosa were observed. Histologically, presence of FAdV-1 in intranuclear inclusion bodies of degenerated glandular epithelial cells was demonstrated by in-situ hybridization and inflammatory cell infiltration of the lamina propria, submucosa and muscle layer was detected. Tissue samples were investigated by a recently developed real-time PCR and the viral DNA load was calculated from gizzard, liver, spleen and cloacal swabs with the highest amounts of FAdV-1 DNA found in the gizzard. For the first time, successful reproduction of clinical signs in broilers as well as pathological lesions in the gizzard were achieved with a European FAdV-1 isolate displaying some genetic differences to so far reported virulent FAdV-1 from Japan. Furthermore, highest viral load in gizzards could be linked with macroscopical and histological lesions. Therefore, the conducted analyses provide important insights into the pathogenesis of adenoviral gizzard erosion.

Show MeSH

Related in: MedlinePlus

Graphical illustration of the viral load. Viral genome copies per reaction (log10) from a) gizzard, b) liver and c) cloacal swabs calculated by real-time PCR from specific-pathogen-free (SPF) and commercial broilers orally infected with virulent FAdV-1 at 3, 7, 10, 14 and 17 days post infection. Asterisks indicate some samples that turned out positive with specific melting curve analysis but viral genome copies per reaction could not be calculated successfully.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3672026&req=5

Figure 3: Graphical illustration of the viral load. Viral genome copies per reaction (log10) from a) gizzard, b) liver and c) cloacal swabs calculated by real-time PCR from specific-pathogen-free (SPF) and commercial broilers orally infected with virulent FAdV-1 at 3, 7, 10, 14 and 17 days post infection. Asterisks indicate some samples that turned out positive with specific melting curve analysis but viral genome copies per reaction could not be calculated successfully.

Mentions: Cloacal swabs and organ samples collected from broilers experimentally infected with FAdV-1 were investigated by cell culture and real-time PCR. In SPFB, FAdV-1 was recovered from cloacal swabs, gizzard, liver and spleen by cell culture and real-time PCR (Table 2). Virus excretion and presence of live virus in internal organs were noticed until 10 dpi. Viral genome copy numbers were determined and mean values for each time point post infection were calculated. The highest number of excreted FAdV-1 as well as the maximum viral load in gizzard and liver samples was found at 7 dpi (Figure 3). In CB, live virus was recovered from cloacal swabs, gizzard and liver by cell culture, whereas spleen samples were all negative. However, viral genome copy numbers could be determined from cloacal swabs, gizzard, liver and spleen (Table 2) and the highest viral loads were calculated at 10 dpi (Figure 3).


Quantity of virulent fowl adenovirus serotype 1 correlates with clinical signs, macroscopical and pathohistological lesions in gizzards following experimental induction of gizzard erosion in broilers.

Grafl B, Liebhart D, Günes A, Wernsdorf P, Aigner F, Bachmeier J, Hess M - Vet. Res. (2013)

Graphical illustration of the viral load. Viral genome copies per reaction (log10) from a) gizzard, b) liver and c) cloacal swabs calculated by real-time PCR from specific-pathogen-free (SPF) and commercial broilers orally infected with virulent FAdV-1 at 3, 7, 10, 14 and 17 days post infection. Asterisks indicate some samples that turned out positive with specific melting curve analysis but viral genome copies per reaction could not be calculated successfully.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3672026&req=5

Figure 3: Graphical illustration of the viral load. Viral genome copies per reaction (log10) from a) gizzard, b) liver and c) cloacal swabs calculated by real-time PCR from specific-pathogen-free (SPF) and commercial broilers orally infected with virulent FAdV-1 at 3, 7, 10, 14 and 17 days post infection. Asterisks indicate some samples that turned out positive with specific melting curve analysis but viral genome copies per reaction could not be calculated successfully.
Mentions: Cloacal swabs and organ samples collected from broilers experimentally infected with FAdV-1 were investigated by cell culture and real-time PCR. In SPFB, FAdV-1 was recovered from cloacal swabs, gizzard, liver and spleen by cell culture and real-time PCR (Table 2). Virus excretion and presence of live virus in internal organs were noticed until 10 dpi. Viral genome copy numbers were determined and mean values for each time point post infection were calculated. The highest number of excreted FAdV-1 as well as the maximum viral load in gizzard and liver samples was found at 7 dpi (Figure 3). In CB, live virus was recovered from cloacal swabs, gizzard and liver by cell culture, whereas spleen samples were all negative. However, viral genome copy numbers could be determined from cloacal swabs, gizzard, liver and spleen (Table 2) and the highest viral loads were calculated at 10 dpi (Figure 3).

Bottom Line: Clinically, both infected groups showed significant decrease of weight compared to respective negative control groups.Tissue samples were investigated by a recently developed real-time PCR and the viral DNA load was calculated from gizzard, liver, spleen and cloacal swabs with the highest amounts of FAdV-1 DNA found in the gizzard.For the first time, successful reproduction of clinical signs in broilers as well as pathological lesions in the gizzard were achieved with a European FAdV-1 isolate displaying some genetic differences to so far reported virulent FAdV-1 from Japan.

View Article: PubMed Central - HTML - PubMed

ABSTRACT
In the present study day-old specific-pathogen-free (SPF) and commercial broilers with maternally derived fowl adenovirus serotype 1 (FAdV-1) antibodies were orally infected with a European "pathogenic" FAdV-1, isolated from broilers showing signs of gizzard erosion. During the experiment, broilers were observed and weighed daily up to 17 days post infection (dpi). Clinically, both infected groups showed significant decrease of weight compared to respective negative control groups. Birds were examined by necropsy at 3, 7, 10, 14 and 17 dpi. Pathological changes in the gizzards were noticed in both experimentally infected groups from 7 dpi onwards. Macroscopically, erosion of the koilin layer and inflammation or ulceration of the gizzard mucosa were observed. Histologically, presence of FAdV-1 in intranuclear inclusion bodies of degenerated glandular epithelial cells was demonstrated by in-situ hybridization and inflammatory cell infiltration of the lamina propria, submucosa and muscle layer was detected. Tissue samples were investigated by a recently developed real-time PCR and the viral DNA load was calculated from gizzard, liver, spleen and cloacal swabs with the highest amounts of FAdV-1 DNA found in the gizzard. For the first time, successful reproduction of clinical signs in broilers as well as pathological lesions in the gizzard were achieved with a European FAdV-1 isolate displaying some genetic differences to so far reported virulent FAdV-1 from Japan. Furthermore, highest viral load in gizzards could be linked with macroscopical and histological lesions. Therefore, the conducted analyses provide important insights into the pathogenesis of adenoviral gizzard erosion.

Show MeSH
Related in: MedlinePlus