Title : Bacillus species as direct-fed microbial antibiotic alternatives for aquaculture development and sustainability
Abstract:
Aquaculture is a rapidly expanding farming industry owing to the augmenting demand for food and the notable shortage in natural fish stocks. The aquaculture sector is providing more than 50% of the world’s fish and seafood needs for the continuously growing human population. Nevertheless, intensive aquaculture heightened the menace of pathogenic disease occurrence in the farmed fish species, leading to a massive mortality. To control these devastating diseases, broad-spectrum antibiotics have been extensively applied. In addition to antibiotic accumulation in edible fish products, these practices led to spreading of hazardous antibiotic-resistant pathogenic bacteria in culturing aquatic environment, causing a failure of antibiotic treatments, and increasing the risks of the production losses through zoonotic infections. Consequently, developing ecofriendly substitutes to antibiotics that have several health-promoting properties for fish is a promising strategy for aquaculture development and sustainability. Main antibiotic substitutes are probiotics, feed enzymes, prebiotics, para-probiotics, postbiotics and medicinal plants.
Recently, probiotics or direct-fed microbials (DFM) supplementation in aquaculture industry has gained considerable attention. The use of DFM has proven strong potential for improving aquaculture sustainability by disease control and enhancement of water quality, growth, immunity, and stress resistance of cultured aquatic animal species. Among probiotic candidates, Bacillus species that are generally recognized as safe (GRAS) have the advantage to produce spores. This increases their shelf life, viability and survival in extreme pH and temperature conditions. In addition, they can colonize host tissues where they secrete beneficial enzymatic activities such as phytases, xylanases and β-glucanases. These enzymes can help in neutralizing anti-nutritional factors and improve feed conversion rates. In addition to the secretion of extracellular digestive enzymes, Bacillus strains are widely applied in aquaculture industry as DFM due to their ability to produce various factors that improve digestion, nutrient absorption, pathogens’ inhibition, immune response to infections, gut integrity preservation, and thus the fish growth performance. A proper selection of the Bacillus probiotic strains is required in order to confer optimal beneficial effects on the aquatic animal host. The present communication focuses on the general functional, safety and technological screening criteria for selection of ideal Bacillus probiotics as feed supplements as well as their mechanism of action and beneficial effects on fish species for improving production performance and health status.
Audience take-away:
- The audience will learn from the presentation the beneficial effects of using Bacillus probiotics as direct-fed microbials (DFM) in aquaculture industry.
- The audience will be able to use Bacillus probiotics DFM for improving aquaculture sustainability
- Use Bacillus probiotics DFM will help the audience for improving aquaculture sustainability by disease control and enhancement of water quality, growth, immunity, and stress resistance of cultured aquatic animal species.
- Yes, marine faculty and research center can use thus research to expand their research and teaching
- Yes, this provides a practical solution to control devastating diseases disease and enhance growth, water quality, immunity, and stress resistance of cultured aquatic animal species.
