The Application of Automatic Systems in Shrimp Production as Tools to Improve Feed Management

Abstract

Shrimp production has been one of the primary products of aquaculture due to its high value and product acceptance on the global market. The continued success of the shrimp industry will rely on improving feed management practices and reductions in labor costs. As feed is one of the main operating costs in shrimp aquaculture, much research effort has been put into developing cost-efficient practical diets but feeding protocols have typically received less attention. The repetitive nature of feed dispersion in aquaculture resulted in the integration of automatic feeders in shrimp production systems, which allows expansion of the number of meals without compromising labor costs. Hence, it was the overall objective of this doctoral research project to study and explore the potential for improvement of various feed management protocols for automatic feeders in shrimp production as well as evaluate overall role of automation in shrimp farming. In later stages, the project focused on exploring the potential of recently available passive acoustic feeding systems in determining potential dietary preferences among different commercial diets with various protein sources. A 90-day outdoor pond production trial evaluated the development of standard feeding protocol’s (SFP) for automatic feeding systems to maximize growth rates. Four treatments including: three fixed feeding treatments of 130, 145 and 160% of a SFP (SFP+30%, SFP+45%, SFP+60%, respectively) were offered to shrimp using automatic timer-feeders, and a fourth treatment utilized an on-demand AQ1 acoustic feeding system. In general, increased feed inputs resulted in higher production and best response was achieved with the AQ1 system which offered higher feed inputs resulting in larger shrimp and yields. Using cumulative data to date, a standard protocol for timer feeders (SPTF) was established and used in the second trial. This trial consisted of a 90-day pond production cycle which was conducted using the SPTF to evaluate shrimp production using different feeding schedules. Four treatments were utilized in this trial including: three fixed feeding treatments based on SPTF Day, SPTF Night and SPTF 115% 24hr were offered using automatic timer-feeders, while a fourth on demand treatment utilized AQ1 acoustic feeding system. A 11-wk growth trial was conducted in a parallel green-water semi-recirculating tank system that aimed at evaluated additional feeding protocols. Results for the pond trial further confirm higher yields with AQ1 acoustic feeding system and showed no statistical differences among timer feeder treatments, indicating no effect on time (day vs night vs 24 hrs) of feeding. Results in the tank trial indicated a relationship between growth response to increasing feed inputs and number of meals rather than feeding schedule alone. After two production cycles that validated the higher production efficiency of the acoustic system, all ponds were subsequently equipped with this technology and a third and last 90-day outdoor production trial was conducted to evaluate if shrimp preferred a specific protein source fed on demand. Four treatments consisted of a 35% crude protein commercial diet with different protein sources: all-plant, 8% poultry meal (PM), 8% fish meal (FM) and 12% FM. No statistical differences were observed in any of the main production parameters suggesting that shrimp did not clearly favor a particular diet when fed on demand. In conclusion, the research conducted throughout this doctorate provides further insight towards the establishment of effective feeding protocols for automatic feeders in shrimp production, and confirms that passive acoustic demand feeders are currently the most effective feed management tool in shrimp pond production. While validating acoustic feeders, we were also able to confirm that feed intake and growth were not compromised when shrimp were fed alternative protein based diets. This data contributes to the discussion of how can feed additives or physical properties of the diets can be used to further improve effectiveness of these feeders.