<abstract xmlns="http://www.w3.org/1999/xhtml">

<sec>
<h3>Introduction</h3>
<p>The disease caused by carp edema virus (CEV) manifests with lethargy as a primary sign; this observation in koi in Japan gained the disease the name koi sleepy disease (KSD). In the years following the discovery of the virus in Japan, KSD cases have been noted in the UK in koi and common carp. Conducting research in order to expand knowledge of the processes of distribution of CEV in infected fish organs will be helpful for eradication and diagnostic purposes.</p>
</sec>
<sec>
<h3>Material and Methods</h3>
<p>Carp edema virus–affected fish with clinical signs of KSD were experimentally cohabited with common carp fry (30 fish). Three fish were euthanised by bath in a 0.5 g L<sup>−1</sup> tricaine solution at one week intervals (7, 14, 21 and 28 days post cohabitation). Tissue samples from the brain, gills, spleen, kidney, intestines and skin were collected, and the total DNA was extracted and tested by real-time PCR.</p>
</sec>
<sec>
<h3>Results</h3>
<p>By the seventh day post infection, CEV DNA was most often found in the skin, gills and brain and less frequently in the kidney and intestines. In many of the common carp fry, CEV DNA could typically be found in several organs of each individual fish, although it was only found in one sample of spleen tissue.</p>
</sec>
<sec>
<h3>Conclusion</h3>
<p>In this experimental study the pathogenesis of the CEV infection process was shown, the high infectivity of CEV was confirmed and the best organs were determined for sampling in CEV-infection experimentation. The real-time PCR method used in our cohabitation experiments was shown to be useful at the clinical and asymptomatic stage of virus infection.</p>
</sec>
</abstract>

Introduction
The disease caused by carp edema virus (CEV) manifests with lethargy as a primary sign; this observation in koi in Japan gained the disease the name koi sleepy disease (KSD). In the years following the discovery of the virus in Japan, KSD cases have been noted in the UK in koi and common carp. Conducting research in order to expand knowledge of the processes of distribution of CEV in infected fish organs will be helpful for eradication and diagnostic purposes.


Material and Methods
Carp edema virus–affected fish with clinical signs of KSD were experimentally cohabited with common carp fry (30 fish). Three fish were euthanised by bath in a 0.5 g L−1 tricaine solution at one week intervals (7, 14, 21 and 28 days post cohabitation). Tissue samples from the brain, gills, spleen, kidney, intestines and skin were collected, and the total DNA was extracted and tested by real-time PCR.


Results
By the seventh day post infection, CEV DNA was most often found in the skin, gills and brain and less frequently in the kidney and intestines. In many of the common carp fry, CEV DNA could typically be found in several organs of each individual fish, although it was only found in one sample of spleen tissue.


Conclusion
In this experimental study the pathogenesis of the CEV infection process was shown, the high infectivity of CEV was confirmed and the best organs were determined for sampling in CEV-infection experimentation. The real-time PCR method used in our cohabitation experiments was shown to be useful at the clinical and asymptomatic stage of virus infection.

Distribution of carp edema virus in organs of infected juvenile common carp

Journal of Veterinary Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

{"article-title":"Distribution of carp edema virus in organs of infected juvenile common carp"}

Introduction
The disease caused by carp edema virus (CEV) manifests with lethargy as a primary sign; this observation in koi in Japan gained the disease the...

Dpi	Fish number			Cycle threshold for a given tissue type
		Brain	Gills	Kidney	Intestines	Skin	Spleen
7	1	−	+/34.37	−	−	+/29.98	+/38.01
	2	+/36.24	+/36.06	−	+/39.97	+/24.19	−
	3	+/31.97	+/34.36	+/36.94	+/40.06	+/26.66	−
	4	−	+/38.13	+/40.83	−	+/32.54	−
14	5	+/38.93	+/39.12	−	−	+/32.33	−
	6	+/32.95	+/33.74	+/35.64	−	+/28.10	−
	7	+/40.21	+/38.52	−	+/38.83	+/37.18	−
21	8	+/38.42	+/37.75	+/34.87	+/37.97	+/28.21	−
	9	+/39.10	+/35.67	−	+/40.57	+/36.79	−
	10	−	−	−	−	−	−
28	11	−	−	−	−	−	−
28	12	−	−	−	−	+/33.79	−

Distribution of carp edema virus in organs of infected juvenile common carp

Data publikacji: 20 wrz 2023

Zakres stron: 333 - 337

Otrzymano: 08 mar 2023

Przyjęty: 10 sie 2023

DOI: https://doi.org/10.2478/jvetres-2023-0049

Słowa kluczowe
fish, common carp, koi sleepy disease syndrome (KSD), carp edema virus (CEV)

© 2023 Marek Matras et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Fig. 1.

Fig. 2.

Fig. 3.

Real-time PCR results in fish experimentally infected with carp edema virus and maintained at 14°C (second iteration)

Real-time PCR results in fish experimentally infected with carp edema virus and maintained at 14°C (first iteration)

Distribution of carp edema virus in organs of infected juvenile common carp

Data publikacji: 20 wrz 2023

Zakres stron: 333 - 337

Otrzymano: 08 mar 2023

Przyjęty: 10 sie 2023

DOI: https://doi.org/10.2478/jvetres-2023-0049

Słowa kluczowefish, common carp, koi sleepy disease syndrome (KSD), carp edema virus (CEV)

© 2023 Marek Matras et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Fig. 1.

Fig. 2.

Fig. 3.

Real-time PCR results in fish experimentally infected with carp edema virus and maintained at 14°C (second iteration)

Real-time PCR results in fish experimentally infected with carp edema virus and maintained at 14°C (first iteration)

Słowa kluczowe
fish, common carp, koi sleepy disease syndrome (KSD), carp edema virus (CEV)