WWW.WA S .ORG • WORLD AQUACULTURE • MARCH 2022 51 ( C O N T I N U E D O N P A G E 5 2 ) 104-188 mg/L as CaCO3 and hardness to 78 mg/L as CaCO3. Near harvest, the daily feed allowance reached 1,075 kg/ ha. Despite the high loading rate, total ammonia never exceeded 1.5 mg/L, although nitrite concentration was elevated. Nitrite was measured with a LaMotte test kit with maximum range of 0.8 mg/L but the water sample was not diluted so the concentration was likely higher than the maximum of the analytical range. A loss of appetite on fish was observed at peak feed loading. Due to difficulties with communication, farm personnel were late to operate the fish solid waste extractor device. By harvest time, the fish waste removal device was not working properly because of an air lock in the suction line. Budget The major cost items include feed, fingerlings, electric power and labor. All expenses were in Honduras Lempira and were then converted into US$ at a rate of 24.10 Lempira/$ for preparation of the budget. Feed price was obtained from a feed distributor, not the wholesale price from the mill. Fingerling cost includes the price of buying small fingerlings and growing them to stocker size. The electric power rate is US$ 0.196/kW. The Mission employed local women, especially single mothers, to feed fish. Weekly pay was twice as much as the standard wage for farmworkers in western Honduras. At the same time, facilities are used for training purposes on the education of young boys. The total expenses for this trial were US$ 3,6231.60. The cost of building one fish raceway was approximately US$ 2,600 but ponds were deepened, increasing unit costs to US$ 3,000. For six raceways, the total fixed costs of US$ 18,000 were depreciated over five yearsr. For revenue, the Mission had some problems selling fish because they were not prepared for fish production with this new technology. At the time of harvest in this trial, the Mission had a contract with a supermarket in Honduras that gave the Mission a good price, helping with the social endeavor of the project. Overall, FIGURE 5. Growth of red tilapia fed two commercial 32-percent protein diets, averaged by treatment, from stocking to harvest. FIGURE 6. Fulton conditon factor (K) of red tilapia fed two commercial 32-percent protein diets was similar. FIGURE 7. Early morning water temperature (C) averaged by treatment, compared with the open pond. FIGURE 8. Early morning dissolved oxygen concentration (mg/L) averaged by treatment, compared with the open pond.
RkJQdWJsaXNoZXIy MjExNDY=