Nghia Phan, MSc, a Stirling University alumnus, working with Dr Phu and Dr Thinh from the College of Aquaculture and Fisheries, Can Tho University, reports on a new project to develop and test Operational Welfare Indicators (OWIs) for the stripped snakehead fish culture in Vietnam.
Hi everyone, we are the group members developing OWIs for snakehead fish cultured in Vietnam. It has been the first few days since the project started, and we want to share our experience doing the job and how we are going to do this project.
Operational Welfare Indicators and Snakehead Fish
Two snakehead fish
OWIs are a set of indicators that farmers and farm managers use to manage animal welfare. There are lab-based OWIs and animal-based OWIs, but this project focuses solely on animal-based OWIs, which include scoring sets for physical appearance, water quality, and behaviour.
A previous project by Phu and his team at Can Tho University examined perceptions of welfare concerning snakehead fish within the value chain in the Mekong River Delta. This study shows that farmers tend to prioritize fish behaviour, appearance, and mortality, while transporters are mainly concerned with mortality rates, indicating a lack of awareness among retailers regarding the impact of killing the animals. This project aims to develop an optimised and user-friendly OWI that various stakeholders in the snakehead fish value chain- farmers, transporters, traders, wholesalers, and retailers- can utilize.
How we do it
We started the project with a trip to a Vibo-dealer farms, an aquacultural drugs producer, in Tra Vinh province, one of the largest snakehead fish farms in the area, featuring over 70 grow-out ponds, each averaging 30,000 fish. Given the large number of ponds and fish to manage, farm managers are regarded as experts in culturing snakehead fish. We were able to interview the managers, as well as discuss and measure water samples, videotape the animal behaviour, and photograph the fish in various settings and sizes.
Water quality was measured on-site using probes (Dissolved oxygen, pH, temperature) and test kits (NO2, NH3/NH4+). Then, the fish from the respective ponds were captured for measurement, and a photo was taken. The majority of the pictures were taken in a white light box, but there are some pictures of the inner organs (throat, gills) that had to be taken under direct sunlight to be able to see the colour differences and symptoms (if there were any). A short questionnaire for the farmers and farm managers was also asked to see their point of view about what a healthy fish is, fish behaviour, and pond.
At the time we visited, all the ponds we visited had no signs of stressed or abnormally behaved fish. The fish, as told by the farm managers, were lying near the surface of the pond, in shade, catching air, and reacting with motion, which is the behaviour of a healthy and happy snakehead. The video below shows the fish weighing around 200-300 grams at 11 a.m.
Snakehead - typical behaviour in a pond
This is a short introduction and update for our project contributing to the Asia Fish Welfare project. We will update you along the way and thank you for reading this. If you have any questions, please email Dr. Phu, project manager tmphu@ctu.edu.vn or Nghia at ndp00009@students.stir.ac.uk.