Technical efficiency analysis of marine shrimp farming (Litopenaeus vannamei) in biofloc and conventional systems: A case study in northeastern Brazil.

Marcelo A.S Rego,Roberta B Soares,Omar J Sabbag,Silvio Peixoto

doi:10.1590/0001-3765201820170953

Abstract

Shrimp farming has a great ecological, economic, and social importance in northeastern Brazil. Although the conventional farming system is widely used, biofloc technology (BFT) system has been developed to reduce environmental impacts and optimizing the production. Thus,the present study evaluated the technical efficiency of production cycles of Litopenaeus vannamei in conventional and BFT systems.We analyzed 48 production cycles in the conventional system in 2013 and 2014 and 9 cycles in the BFT system in 2014 through data envelopment analysis (DEA). The inputs corresponded to the population density (post-larvae m-2), amount of feed (kg ha-1 cycle-1), labor (man ha-1) and power supply (HP ha-1), whereas the yield (kg ha-1 cycle-1) was considered the output. The results indicated four production cycles (7.0%) technically efficient, three in the conventional system and one in the BFT. By comparing the productive systems, there was significant difference in their mean scores of technical efficiency. There was a greater influence of the management inefficiency on the conventional system, while the production scale reduced the average scores of technical efficiency in the BFT system. These results may help to improve the development of sustainable L. vannamei farming in both systems by reducing waste and increasing profits.

Highlights

Marine shrimp farming represents a major rural activity that generates employment and income in Brazil, though its development still finds difficulties (Sampaio et al 2008, Natori et al 2011)
We have previously evaluated the financial indicators and the risk of bioflocs technology system (BFT) and conventional systems (Rego et al 2017a, b), but in this study we focused on the technical efficiency of the production cycle of Litopenaeus vannamei in conventional and BFT systemsin northeastern Brazil
Regarding the technical efficiency scores for all production cycles of the farm in 2013 and 2014, 33.3% and 49.1% corresponded to values equal to and greater than 0.90, analyzedthrough data envelopment analysis with constant (CRS) and variable returns to scale (VRS), respectively (Table III)

Summary

Introduction

Marine shrimp farming represents a major rural activity that generates employment and income in Brazil, though its development still finds difficulties (Sampaio et al 2008, Natori et al 2011). The conventional farming system widely used in northeastern coastis possibly the cause of many negative effects, such as effluent disposal, escape of exotic species to the ecosystem and spread of diseases, among others (De. Lacerda et al 2006, Sousa et al 2006, Abreu et al 2011, Da Silva et al 2016). There have been production losses due to the contamination by shrimp pathogens and the difficulty in regulating enterprises (Abreu et al 2011). The possibility of little or no water exchange is one of the main features of the BFT system, reducing contamination of shrimp by pathogens and the discharge of effluents in the ecosystem, contributing to the acceptance of this activity by the public and competent environmental authorities (Burford et al 2003, Samocha et al 2007, Avnimelech 2012). The ability to withstand high stocking densities, and thereby increase productivity, is the main attraction of the BFT system for entrepreneurs (Browdy and Moss 2005)

Methods

Results

Conclusion