PROCESS SIMULATION, OPERATION COST ESTIMATION AND OPTIMIZATION FOR HIGH-THROUGHPUT CRYOPRESERVATION OF BLUE CATFISH SPERM

Project Summary

Currently there are no planning and optimization resources to expand the laboratory findings demonstrating biological feasibility of cryopreserved fish sperm, and no information base exists for mass production to allow industrial evaluation. Our goal was to model automated high-throughput methods for process evaluation. The objectives were to: 1) use industrial engineering simulation software to model existing production processes; 2) compare high-throughput processing with manual processing, and 3) optimize resource use for both methods. By use of the ARENA software (Rockwell Automation, Inc. Milwaukee, WI) 40 processing steps (Fig.1) were examined using time, cost, and resource parameters. Simulations were done with stochastic data, analyzing values as ranges or distributions. The base model was based on the availability of five workers for processing (e.g. dissecting testes) and procedures developed by Hu et al. (2010 Cryobiology 62:74-82). After 20 simulation replications, for the same output of cryopreserved sperm, the manual method had higher costs (P = 0.000) but a shorter processing time (P = 0.000) based on all 5 people filling straws (only one was needed for automated processing). The software provided an optimization tool (OptQuest, OptTek Systems, Inc., Boulder, CO) for resource utilization within the model. The optimization goal was to minimize daily costs for processing of 20 fish (1,400 straws). The optimized high-throughput process required 2 more persons for testis collection, reduced daily costs from $484 to $427, and shortened the time from 7.89 hr to 5.59 hr. The optimized manual process required 1 less worker, reduced daily costs from $971 to $540, but increased time from 7.05 hr to 7.77 hr. Although optimization could improve efficiency, structural bottlenecks became evident that would slow production mostly because this species requires processing of dissected testes from large fish (>20 kg). This simulation approach would assist design and management of cryopreservation processes and can provide solutions and valuable data for industrial application in catfish and other aquatic species.