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close this bookAquaculture - Training Manual (Peace Corps, 1990, 350 p.)
close this folderChapter twelve: Program design - week three
View the documentSession III-1: Quiz (week three)
View the documentSession III-2: Management plan (part two)
View the documentSession III-3: Equipment shed, feed shed and pump - trainee responsibilities
View the documentSession III-4: Weekly technical report requirements
View the documentSession III-5: Field trips - week three
View the documentSession III-6: Processing of field trip
View the documentSession III-7: Masonry and carpentry projects
View the documentSession III-8: Dissection exercise
View the documentSession III-9: Social awareness
View the documentSession III-10: Personal interview - week three

Session III-2: Management plan (part two)

Note: Please see the section entitled Management Plan (Part One) in Chapter Eleven for the Objectives and Overview of this component and for several important Trainer Notes. This section will contain the major concepts and activities that should be addressed in the sections of the Management Plan that were not discussed in Chapter Eleven.

· Feeding: The Feeding Plan can be broken into three main parts, if preferred. The first part addresses the nutritional needs of the fish and the feed itself, i.e., what nutrients it must provide, the physical characteristics of the feed, etc. The second part addresses feeding amounts and projected schedules for feeding and growth. The third part addresses the actual methods that will be used for providing the fish with the feed.

Part One: Nutritional needs, characteristics of the feed

· The trainee should demonstrate an understanding of trophic levels (this may have been covered in the stocking plan);


· Nutrient requirements of fish. The trainee should be able to list at least some of these, including, at minimum, proteins, carbohydrates and vitamins. The further the trainee can take this the better. The trainer should ask questions about what the different kinds of nutrients do for the fish, and should ask the trainee to try to make an educated estimate about the proportions of each major nutritional component required in the diet;


· Description of the physical form of the feed. Some considerations include: size of the particle in relation to the size of the fish's mouth, sinking or floating characteristics, breakdown time in water, etc.

Part Two: Feeding rate, projected growth, feed conversion

· Determine feeding rate for the first day of feeding. This involves two major considerations: percent body weight the fish can be expected to eat, and the feed conversion ratio (FCR). The order in which these are examined will depend on the trainee;

· In most cases, trainees begin by trying to determine a percent body weight that the fish will consume;

· Once the an amount of feed is determined, the trainee can then try to project the feed conversion ratio in order to calculate how much growth will result from that much food;


· Trainees should demonstrate an understanding of the shape of a normal growth curve, and should understand what a growth rate is. They should understand that growth slows as the animal ages, and that it is significantly reduced upon sexual maturity. They should realize that a very young animal normally requires a higher percentage of its own body weight in feed than a mature animal;


· When the trainee has considered percent body weight as a way of estimating how much the fish will consume, as well as feed conversion ratio, he/she can make a chart with projected feeding rates, feed conversion and growth for the length of the growing period. This can be on either a daily or weekly basis (if the fish are small, the numbers involved will be so small as to be awkward to work with). Weights can be for individual fish or for total weight of fish. The following is an example of the kind of chart referred to here (based on feeding 7 days per week):


Total fish weight (lbs)

% Body Weight per day

Amount to feed/day (lbs)

FCR

Growth(lbs/day)

Week 1

100.0

5

5.0

2:1

2.5

Week 2

117.5

5

5.9

2:1

2.9

Week 3

137.8

5

6.9

2:1

3.4

Week 4

161.6

5

8.1

2:1

4.0

The chart would continue for the length of the growing time.

· Once the trainee has made the appropriate projections, he/she should discuss how adjustments will be made, and acknowledge that although the chart provides a projection, the real results will be observed over time. A similar chart, but with the number spaces blank, should be drawn up to be filled in over the course of raising the fish;


· Adjustments to feeding. This should be based upon fish's feeding response (actual consumption of feed) and information obtained through sampling;

· The trainee should develop a record keeping system for feeding.

Part Three: Actual method of feeding

· How feed will be put into pond;

· Location of feed in pond;

· Time(s) of day fish. will be fed.

Notes:


· Since sampling is an important part of adjusting feeding rates, some trainees may choose to do their sampling section as part of the feeding section. This is fine and should not be discouraged as long as all aspects listed in the sampling section are addressed;


· Analogies are very helpful for thinking about feed as a percent of body weight and feed conversion ratios.


· Fertilization: For some trainees, especially those with no experience at all in fertilizing plants, gardens and lawns, and/or with no biology background, this will be a very difficult section. Some may not even consider fertilization at this stage and may need to add it to their Management Plans a little bit later, after some exposure to outside resources. For most, however, there are at least some basics that can be addressed:

· Why fertilize at all? (Provide nutrients for phytoplankton);

· Algae/plankton. What are they? What kinds of plankton are there? Are there any present in the pond? What role do they play as food for the fish? What effect do they have on oxygen in the pond?


· What nutrients must be provided through fertilization (nitrogen, phosphorous, potassium, others)? Which are limiting, if any?

· What are different types and forms of fertilizer that can be used?

· How much fertilizer should be applied? (This is very difficult for trainees with no experience. Analogies are helpful, but are only relevant if trainee has some analogous experience. Trainers should be flexible here, but do require the trainee to justify his/her decision. Often the trainee will simply elect to start with some very small amount to be safe, then plan to increase the amount in small increments until results are noted);

· Method of application (describe in detail);

· Effects of fertilization. What does the trainee expect they might be? How will they be monitored?

· Trainee should try to remember as much as possible about photosynthesis and respiration;


· Trainee should try to reason out what the dissolved oxygen cycles could be expected to be like in a pond;


· Monitoring plankton populations (turbidity, color, use of light penetration measurements, other observations);

· What happens if there is too much or too little plankton?

· Monitoring oxygen;


· Over-fertilization. What would be the results of over-fertilizing? How would they know? What would they do about it?

· Sampling:
· Methods to be used;
· Schedule (how often, time of day);
· Relationship to feeding schedule;
· How sampling results will be used to make management decisions;
· Data to be collected, observations to be made: general health, growth, reproduction, etc.

· Water quality:


· The number of water quality parameters the trainee considers monitoring will depend on the trainee's knowledge and background. With access to the test kits, he/she can consider parameters which were initially omitted;


· Water quality parameters that will affect the fish: dissolved oxygen, pH, carbon dioxide, alkalinity, hardness, ammonia, etc.;

· Schedules for monitoring water quality (frequency, time of day);

· Methods (techniques, location in pond, depth, etc.).

· Harvesting:
· Methods to be used;
· Projected timing;
· Calculation of yield and production.

· Marketing:
· Gathering information about the market and marketing options;
· Determining prices.

· Accounting/Budget:
· Materials and equipment;
· Running account of all costs and income.

Note: The sections on harvesting and marketing do not need to be developed in too much detail during the initial development of the Management Plan.