Tuesday 28 October 2014

Day 45- Last final Sampling, Betting and Flight.

Emilie and Jemimah counting batches of 30 subjects (credits: Pierre-Olivier Maquart).

Today our fish were sampled for the last day. After 24 hours of fasting, in the morning at 8 am a large wooden platform was pulled close and adjacent to the trial cages.

Sacrificed fish for analyses (credits: Pierre-Olivier Maquart).
Then from each cage all the fish were firstly crowded up in the cage then gently netted out, grouped by 30 into bowls with water containing plastic baskets. Then each batch (of 30 subjects), was weighted due to gaining the ABW (average body weight).
From each sampled basket, one fish was taken and sacrificed for further analyses on whole body composition. Euthanasia was realized by anesthetic  an overdose of clove oil.

Before the sampling day, I made a challenge  with Felix the person who feed the fish  on the growth results of the different trial cages: We bet, only according to our eyes and the experience of running the trial for the last 4 weeks, which diet made the fish grow the  fastest. The reward in case of losing was a Swiss knife from me, and tilapia with banku from Felix.
Unfortunately I am not allowed to reveal the results here concerning this trial, but I can say that Felix had very good eye and I lost!!
Feeder Felix on work (credits: Francis Murray).

The accuracy of feeders in observing fish behavior during feeding and their growth is very important for the welfare of fish farm, since they have the crucial importance in up-growing the fish avoiding as much as possible the wasting of feed, and making it been eaten all and converted in flesh. 
Unfortunately nowadays many fish farms in Africa undervalue the key role of fish-feeders, and usually many un-trained or not careful people are employed, with the unhappy result in bad economic balances for feed wastes for overfeeding or careless, until the crash of the whole farm in a couple of years.

 So, because of excellent feeder’s  eye,  before leaving the tilapia farm I had to give him my Swiss knife (unfortunately hazards are  not my business!).
As the afternoon arrived I had to leave to reach Accra airport for check-in for my return flight, and I said goodbye to  all the supervisors, Emilie, Pierre, colleagues and sampling team.

Grown-up tilapia juveniles during sampling in counting baskets (credits: Pierre-Olivier Maquart).

No comments:

Post a Comment