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| Image: James Halliday |
Disease outbreaks in the shrimp farming industry have caused substantial economic losses around the world and, in particular, the recent “early mortality syndrome” (EMS) due to plasmids in Vibrio bacteria is a growing threat, Nicholas Romano writes in The Global Aquaculture Advocate.
In addition to decreasing immunity, EMS causes substantial hepatopancreatic damage to shrimp, which gradually induces mass mortalities. Moreover, with a greater restriction or altogether ban on antibiotic use, this can leave shrimp farmers with fewer options to protect their animals against bacterial diseases.
Organic acids in shrimp feeds
In response, researchers have investigated environmentally-friendly dietary alternatives as potential prophylactics. One potential alternative are organic acids, which are “Generally Regarded as Safe,” or GRAS, and that have been used for decades with success as growth promoters and antimicrobials in the terrestrial livestock feed industry. However, not much is known about their efficacy to shrimp farming productivity.
Recently, our laboratory research group conducted a controlled study where Pacific white shrimp (Litopenaeus vannamei) were fed with different dietary levels of a prototype microencapsulated organic acids blend (OAB) at 0 (control), 1, 2 or 4 percent and evaluated their growth performance, phenoloxidase (PO) activity and hepatopancreatic histopathology after 50 days. Dry matter and phosphorus utilisation efficiency were also determined. At the end of the feeding trial, shrimp were challenged with pathogenic Vibrio harveyi and their survival monitored along with the associated changes to immunity and hepatopancreatic histopathology.
Read the full article in The Global Aquaculture Advocate HERE.
In addition to decreasing immunity, EMS causes substantial hepatopancreatic damage to shrimp, which gradually induces mass mortalities. Moreover, with a greater restriction or altogether ban on antibiotic use, this can leave shrimp farmers with fewer options to protect their animals against bacterial diseases.
Organic acids in shrimp feeds
In response, researchers have investigated environmentally-friendly dietary alternatives as potential prophylactics. One potential alternative are organic acids, which are “Generally Regarded as Safe,” or GRAS, and that have been used for decades with success as growth promoters and antimicrobials in the terrestrial livestock feed industry. However, not much is known about their efficacy to shrimp farming productivity.
Recently, our laboratory research group conducted a controlled study where Pacific white shrimp (Litopenaeus vannamei) were fed with different dietary levels of a prototype microencapsulated organic acids blend (OAB) at 0 (control), 1, 2 or 4 percent and evaluated their growth performance, phenoloxidase (PO) activity and hepatopancreatic histopathology after 50 days. Dry matter and phosphorus utilisation efficiency were also determined. At the end of the feeding trial, shrimp were challenged with pathogenic Vibrio harveyi and their survival monitored along with the associated changes to immunity and hepatopancreatic histopathology.
Read the full article in The Global Aquaculture Advocate HERE.
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