IMPROVING SHRIMP HEALTH WITH SULPHATED POLYSACCHARIDES EXTRACTED FROM SEAWEED TO REDUCE DISEASE MORTALITIES
Working towards a sustainable aquaculture industry, it is very important to take into account the prevention of possible diseases. However, many of the conditions under which shrimp are being produced may result in stressful conditions for both the pond environment and the shrimp and thus present opportunities for infectious diseases. There are several strategies that can be applied to reduce the chances of diseases, while taking into account the sustainability of production. Among them are biosecurity and good production management, but also preventive strategies are used to improve the health of shrimp so that they are more resistant to possible diseases.
Interest in the use of marine algae in animal production is increasing, mainly due to the wide range of biological activities attributed to it, such as immunomodulatory, antioxidant and antiviral properties. Using the vast sustainable resources of marine algae off the coast of Brittany, France and in collaboration with several research bodies, Olmix has been able to isolate, identify and concentrate sulphated polysaccharides that have different activities to support the general health of animals. Some of these isolated polysaccharides include activities such as immunomodulation, the improvement of lipid metabolism, mucin secretion and the strengthening of intestinal barrier functions.
Using these resources, that come from the same environment in which the shrimp grow, Olmix has been able to demonstrate that polysaccharides alone or in combination can help improve the health of shrimp so that they can better cope with diseases. Knowing that most diseases enter orally, a combination of polysaccharides with synergistic functions was put together to improve the health of shrimp with the immunomodulator MSPimmunity and to improve the intestinal barrier with MSPbarrier.
The following test was carried out at the CIBNOR facilities in La Paz, Mexico. After a period of acclimatization, the shrimp were kept in 1000-L tanks at a density of 120 animals/m2 and randomly assigned to one of the 5 treatments in triplicate. The treatments included a positive and negative control, and 4 different inclusion levels of the polysaccharides MSPimmunity and MSPbarrier (0.1, 0.2, 0.3 and 0.5%), in a blind test. After 4 weeks of feeding with the different diets, the shrimp were subjected to a bath challenge with Vibrio parahaemolyticus causing AHPND. The mortalities were recorded daily.
Analyzing the results of the test, it is evident that with an inclusion of 0.5% of the MSPs in the diet, the survival rate of the shrimp challenged with the pathogen causing AHPND was significantly improved. In this test it is seen that the polysaccharides extracted from seaweed can improve the health of the shrimp naturally.
