In vitro assay to determine inactivation of Toxoplasma gondii in meat samples.

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F62157124%3A16170%2F24%3A43881162" target="_blank" >RIV/62157124:16170/24:43881162 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1016/j.ijfoodmicro.2024.110643" target="_blank" >https://doi.org/10.1016/j.ijfoodmicro.2024.110643</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijfoodmicro.2024.110643" target="_blank" >10.1016/j.ijfoodmicro.2024.110643</a>

Result language

angličtina

Original language name

In vitro assay to determine inactivation of Toxoplasma gondii in meat samples.

Original language description

Consumption of raw and undercooked meat is considered as an important source of Toxoplasma gondii infections. However, most non -heated meat products contain salt and additives, which affect T. gondii viability. It was our aim to develop an in vitro method to substitute the mouse bioassay for determining the effect of salting on T. gondii viability. Two sheep were experimentally infected by oral inoculation with 6.5 x 104 oocysts. Grinded meat samples of 50 g were prepared from heart, diaphragm, and four meat cuts. Also, pooled meat samples were either kept untreated (positive control), frozen (negative control) or supplemented with 0.6 %, 0.9 %, 1.2 % or 2.7 % NaCl. All samples were digested in pepsin-HCl solution, and digests were inoculated in duplicate onto monolayers of RK13 (a rabbit kidney cell line). Cells were maintained for up to four weeks and parasite growth was monitored by assessing Cq-values using the T. gondii qPCR on cell culture supernatant in intervals of one week and Delta Cq-values determined. Additionally, 500 mu L of each digest from the individual meat cuts, heart and diaphragm were inoculated in duplicate in IFN gamma KO mice. Both sheep developed an antibody response and tissue samples contained similar concentrations of T. gondii DNA. From all untreated meat samples positive Delta Cq-values were obtained in the in vitro assay, indicating presence and multiplication of viable parasites. This was in line with the mouse bioassay, with the exception of a negative mouse bioassay on one heart sample. Samples supplemented with 0.6 %-1.2 % NaCl showed positive Delta Cq-values over time. The frozen sample and the sample supplemented with 2.7 % NaCl remained qPCR positive but with high Cq-values, which indicated no growth. In conclusion, the in vitro method has successfully been used to detect viable T. gondii in tissues of experimentally infected sheep, and a clear difference in T. gondii viability was observed between the samples supplemented with 2.7 % NaCl and those with 1.2 % NaCl or less.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

40301 - Veterinary science

Project

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Continuities

O - Projekt operacniho programu

Publication year

2024

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

International Journal of Food Microbiology

ISSN

0168-1605

e-ISSN

1879-3460

Volume of the periodical

416

Issue of the periodical within the volume

MAY

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

8

Pages from-to

1-8

UT code for WoS article

001201861700001

EID of the result in the Scopus database

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