“The shrimp industry is in pursuit of more sustainable and beneficial dietary feeds, and it is important to understand how functional ingredients, such as krill meal, can lead to better outcomes,” said Lena Burri, director R&D, animal nutrition and health, Aker BioMarine.
That Antarctic krill-harvesting company conducted the research along with experts based at India’s Central Institute of Brackishwater Aquaculture (ICAR).
Their newly released paper, published in the journal Aquaculture, concluded that krill meal is a beneficial functional ingredient when used in Whiteleg shrimp (Penaeus vannamei) feed.
The feeding trial found that inclusion of 4 to 6% krill meal in the diet can lead to higher body weight and greater survival among the shrimp.
Run from the ICAR facility in India, the eight-week feeding trial analyzed the impact of krill meal on shrimp diets with moderate (12%) and low (6%) fishmeal concentrations.
Varying amounts of krill, between 0 to 6%, were added to these diets, which the shrimp received three times daily throughout the experiment.
The findings suggest that shrimp fed 6% krill meal in the diet had the highest body weight at the end of the study. The team saw that shrimp survival was significantly increased in the groups fed 4% and 6% krill meal in the diet.
When 6% krill meal was included in the diet, the shrimp showed a higher content of n-3 polyunsaturated fatty acids, while 2% krill meal in a diet containing 12% fishmeal significantly increased the expression of six immune-related genes in the hepatopancreas of the shrimp, found the team.
The experimental diets did not affect feed conversion ratio, protein efficiency ratio or apparent protein utilization, noted the researchers.
They determined that an inclusion level of at least 4% krill meal would allow a measurable difference in growth performance.
“The results of this experiment show that krill meal, when supplemented in amounts between 4 and 6%, is a beneficial functional ingredient for both moderate and low fishmeal diets. This finding is based on the increased growth performance in the groups consuming krill meal and overall improved survival rates, leading us to our conclusion that krill meal can be a viable supplement to fishmeal in shrimp feeds,” said Dr Ambasankar, ICAR.
Leading shrimp exporter
India is a major exporter of shrimp to the US, European and Asian markets.
“India’s position in the shrimp industry will depend on its ability to remain competitive, to be run sustainably and to meet higher productivity targets – through bigger and healthier shrimp,” commented Atul Barman, director and general manager, Aker BioMarine India.
Title: Growth, fatty acid composition, immune-related gene expression, histology and haematology indices of Penaeus vannamei fed graded levels of Antarctic krill meal at two different fishmeal concentrations
Authors: Ambasankar et al