CPF clarifies blackchin tilapia issue

Prasit Boondoungprasert, chief executive of Charoen Pokphand Foods PCL (CPF), has clarified to The Nation Group that its research project on blackchin tilapia was aimed at improving the genetics of Nile tilapia to reduce inbreeding in existing species. 

The research led to the request to import fish from Ghana in 2006. At that time, this fish species had no Thai name, so it was listed as "Nile tilapia" with the scientific name Sorotherodon melanotheron and the common name "blackchin tilapia".

Timeline of Blackchin Tilapia Importation and Management

In 2006, fish fry were imported from Ghana, but the target of 5,000 fish was not met. The actual import took place in 2010, with only 2,000 fry successfully imported. When the 1-gram fry arrived at Suvarnabhumi Airport, all procedures were carried out in accordance with the guidelines provided to the Commission on Higher Education, Science, Research and Innovation (CHE) and a sub-commission. 

The process was supervised and inspected by relevant officials as per regulations.

On December 22, 2010, at around 8pm, CPF picked up the blackchin tilapia fry at the Suvarnabhumi Fish Quarantine Station and found that a significant portion of the fry – more than 70% – had died because of transport conditions, likely as the fry were very small and had endured a journey of more than 35 hours from Ghana to Thailand. 

The remaining fry were taken to the Yi San fish farm in Samut Songkhram province, where it was found that 1,400 fry had died in transit, leaving only 600 weak fish.

At around 11pm, the 600 weak fish were quarantined in an 8-tonne round cement pond under a closed system at the Yi San farm, following biosecurity standards. The 1,400 dead fry were preserved in formalin before being disposed of through burial. CPF is confident that no blackchin tilapia escaped.

Between December 24, 2010, and January 2, 2011, the caretakers consulted with the Department of Fisheries regarding the weak fry, which were insufficient for research. The officials advised sending samples of the fish preserved in formalin to the Department of Fisheries.

In the second week, 50 samples were preserved in concentrated formalin for evidence, and on January 6, 2011, the samples were delivered to the Department of Fisheries, and the project was formally closed.

CPF Research Halted in 2011

Because of the continuous deaths of the fry in the quarantine pond from December 22, 2010, to January 6, 2011, the research plan was abandoned, as the remaining fish were insufficient for study. CPF researchers obtained permission to destroy the fry with concentrated chlorine and ended the project. The Department of Fisheries was notified, and the fish remains were handed over to the authorities.

CPF complied with the import conditions set by the Committee on Biodiversity and Biosecurity (IBC) as follows:

Condition 1: Upon completion of the experiment, the results were to be reported to the Department of Fisheries. Since all the fry died within 16 days of quarantine, failing to meet the research objectives, the company decided not to continue the study and destroyed the remaining fish, notifying the Department of Fisheries on January 6, 2011.

Condition 2: The Department of Fisheries was to collect fin samples from at least three fish without killing them. Fin collection was to occur during the research phase when the fish had grown to an appropriate size. However, because of the fishes’ weakness and eventual death during the 16-day quarantine, fin samples could not be collected.

Condition 3: If the study did not achieve its goals and the research was discontinued, all remaining fish were to be destroyed, and the Department of Fisheries was to be notified to inspect the destruction process. CPF reported to the Department of Fisheries on January 6, 2011, submitting 50 fish remains for inspection. All damaged fish were destroyed by placing them in a quarantine pond with 100ppm of concentrated chlorine, then preserved in formalin and buried at a depth of approximately 50 centimetres, covered with lime, and buried in soil.

Observations from CPF regarding blackchin tilapia research in 2020 and 2022

Prasit said the reference to the two research papers was solely to provide information based on the findings. The studies focused on the genetic diversity of blackchin tilapia populations and the analysis of the spread of blackchin tilapia.

The 2020 research by the Department of Fisheries concluded that blackchin tilapia in Thailand could be divided into two or three subgroups, each with significant genetic differences, indicating multiple origins.

The 2022 study, using different methods, found that blackchin tilapia in Thailand could be divided into several subgroups with minimal genetic differences, suggesting a common origin. However, the same study noted that genetic differences did not correlate with geographical distance. 

For example, fish from Phetchaburi and Samut Songkhram, neighbouring provinces, showed significant genetic differences, while fish from distant Rayong and Prachuap Khiri Khan had closely related genetics.

This suggests that the spread of blackchin tilapia could have been influenced by human activity, whether through illegal breeding, use as bait, or feeding to other fish species.