Microbiological quality ofLitopenaeus vannameiculture using conventional and biofloc systems

Abstract

Shrimp farming is a fast-expanding activity that has supported the growth in the supply of these crustaceans to consumers around the world. However, the end product is vulnerable to contamination at all stages of the process, including the rearing tanks, where current practices prioritize to raise stocking densities and the minimization of water renewal. It is thus important to evaluate the potential of these systems for the proliferation of undesirable microorganisms, which may render the product unfit for human consumption. In the present study, the presence of coagulase-positive Staphylococcus, Salmonella spp., Vibrio spp., and total and thermotolerant coliforms was verified in biofloc tank and conventional pond systems used for the rearing of Litopenaeus vannamei in Pernambuco, Brazil, and the results were compared with the legislation regulating the marketing of fresh shrimp. Samples were collected from two biofloc tanks with a density of 375 shrimp m À2 , and two conventional ponds with 12 shrimp m À2 . None of the samples tested positive for either Salmonella spp. or coagulase-positive Staphylococcus, which is consistent with the legislation. While no standards are defined legally for Vibrio spp. or coliforms, very low concentrations were recorded in both systems, in comparison with other studies. While some variation in bacterial contamination was observed over the rearing process, the end product of both systems was fit for human consumption. The results of the study indicate that, while the water is not renewed in the biofloc system, the development of undesirable microorganisms can be controlled, with no adverse effects for the end product.

Stocking density of red tilapia (Oreochromis sp.) reared in a commercial biofloc system in Colombia

“…or Staphylococcus coagulase, and the concentrations of V. cholerae and coliforms were low. These findings indicated that although fresh water was not added to the biofloc system, the development of undesirable microorganisms was controlled, and no adverse effects occurred on the final product (Brito et al, 2016).…”

All India Institute of Medical Sciences (AIIMS), Delhi: Cyberattack Puts Digitalisation Under Scanner

“…Globally, shrimps represent 15% of the world trade of fish and fishery products in terms of value, and are ranked as second highest food commodity after tuna (FAO, 2016). In recent years, although global farmed shrimp production has increased to 5.7 million tons in 2010 (Brito et al, 2016) and about 25% of shrimp sold on the world market are raised on shrimp farms (Boyd et al, 1998). Shrimp farms operated with good management and business practices can be profitable and benefit the local economy by creating jobs in production, processing, marketing, feed manufacture, transportation and related support services.…”

The Impact of Biofloc Technology on Water Quality in Aquaculture: A Systematic Meta-Analysis

“…Microbial flocs are created when these bacteria join forces with organic residue particles and other microbes. Microalgae and bacteria recycle excess nutrients in the water such as phosphorus and nitrogen, and also take up these substances, which help to keep harmful substances like ammonia under control [17]. Temperature, salinity, pH, alkalinity, hardness, dissolved oxygen (DO), total ammonia nitrogen (TAN), and orthophosphate are important parameters that should be continuously monitored in BFT [18].…”