Question: feeding requirements in order to avoid over or under feeding...
In order to avoid over or under feeding the fish, the right amount of feed must be given each time. The amount of feed to be provided to the fish per day, the feeding rate (ration), is dependent on the fish’s body weight. Fish adjust their food consumption rates to meet their metabolic energy requirements. Therefore, the required ration varies with time during the production cycle depending on:
a. the fish’ size (i.e. its average weight)
b. the pond water quality - notably in terms of water temperature, dissolved oxygen and pollutant levels.
The amount of feed required per ration can be estimated with the help of a feeding chart and calculated as follows:
= average fish size (weight) x feed rate (%) x total number of fish in the pond.
i) If a catfish of 10 grams requires a ration of 10% of its body weight, how much food should it be given per day? If there are 500 fish in the pond, then how much total food should be weighed out?
ii) If a catfish fish of 250 g requires a ration of 2% of its body weight, how much food should it be given per day? What about for 1,000 fish (express your answer in kg)?
Feeding conversion ratios (FCR):
The Feed Conversion Ratio (FCR) is the amount of food required to produce a unit of fish (see equation 6 below). It is an indicator of the:
- performance of a feed,
- performance of the person feeding the fish and the fishes health
- cost-effectiveness of using a particular feed.
FCR= total amount of food given (kg)/total amount of fish produced (kg)
Cost= Amount of feed required to produce 1 kg of fish (FCR) x Unit Cost of feed
i) If at the end of a production cycle, a total of 175 kg of fish are harvested
from a pond and a total of 225 kg of feed was fed to the fish during production,
how much feed was required (used) to produce each kilogram of fish harvested? Assume that we started with 10 kg of fish stocked.
ii) If each ton of feed costs $500, how much did it cost to produce 1 kg