Effect of haemolysis and repeated freeze-thawing cycles on wild boar serum antibody testing by ELISA

BMC Research Notes

Christian Gortázar¹  Mariana Boadella¹ 

[1] IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13071 Ciudad Real, Spain

关键词: Wildlife disease monitoring;    Serological surveillance;    Blood sample mishandling;    Aujeszky's disease;   

Others  :  1166948
DOI  :  10.1186/1756-0500-4-498

 received in 2011-06-17, accepted in 2011-11-16,  发布年份 2011

【 摘 要 】

Background

Monitoring wildlife diseases is needed to identify changes in disease occurrence. Wildlife blood samples are valuable for this purpose but are often gathered haemolysed. To maximise information, sera often go through repeated analysis and freeze-thaw cycles. Herein, we used samples of clean and haemolysed Eurasian wild boar (Sus scrofa) serum stored at -20°C and thawed up to five times to study the effects of both treatments on the outcome of a commercial ELISA test for the detection of antibodies against Suid Herpesvirus 1 (ADV).

Results

The estimated prevalence of antibodies against ADV was 50-53% for clean and haemolysed sera. Hence, haemolysis did not reduce the mean observed serum antibody prevalence. However, 10 samples changed their classification after repeated freeze-thawing. This included 3 (15%) of the clean sera and 7 (41%) of the haemolysed sera.

Conclusions

We recommend (1) establishing more restrictive cut-off values when testing wildlife sera, (2) recording serum quality prior to sample banking, (3) recording the number of freezing-thawing cycles and (4) store sera in various aliquots to reduce repeated usage. For instance, sera with more than 3 freeze-thaw cycles and a haemolysis of over 3 on a scale of 4 should better be discarded for serum antibody monitoring. Even clean (almost not haemolysed) sera should not go through more than 5 freeze-thaw cycles.

【 授权许可】

   
2011 Boadella et al; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

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