Download Improvement in the immune response and disease resistance of the

Improvement in the immune response and disease resistance of the
mud crab, Scylla paramamosain by using diets supplemented with
either individual or combined probiotics, Bacillus subtilis E20 and
Lactobacillus plantarum 7-40,
Y. L. Shiu1, C. H. Chiu 2, C. H. Liu1*
1
Department of Aquaculture, National Pingtung University of Science and
Technology, Pingtung, Taiwan, 912, Republic of China
2
Department of Food Science, National Pingtung University of Science and
Technology, Pingtung, Taiwan, 912, ROC
Abstract
The use of beneficial bacteria offers a promising approach to prevent infection
from pathogens and was shown to help reduce mortality after infection in aquaculture.
In this study, diets incorporating individual or combined species of probiotics,
Bacillus subtilis E20 and Lactobacillus plantarum 7-40, were fed to the mud crab,
Scylla paramamosian, for 28 days to evaluate the growth performance, and immune
response and disease resistance to Vibrio parahaemolyticus. The optimal
concentration of B. subtilis E20 in the diet was analyzed by tracking the same criteria
after 28 days of feeding. No significant differences in growth performance or immune
parameters of total haemocyte counts, respiratory bursts, superoxide dismutase, or
glutathione peroxidase were recorded in the two trials. Crabs fed the B. subtilis
E20-containing diet had significantly increased phenoloxidase (PO) activity,
phagocytic activity, and disease resistance compared to crabs fed the control diet and
the diet containing the two probiotics in equal proportions. In addition, the mortality
of crabs fed the B. subtilis E20-containing diet was significantly lower than that of
crabs fed the L. plantarum 7-40-containing diet. Lactobacillus plantarum 7-40 had a
great inhibitory effect on the growth of B. subtilis E20, which may have led to the
decreased probiotic effect of the mixed probiotics-containing diet. An analysis of the
optimal level of B. subtilis E20 in the diet showed that crabs fed the B. subtilis
E20-containing diet at a level of 1010 colony-forming units kg-1 had the best immune
response of PO and phagocytic activities, and disease resistance in the second trial.
Keywords: Scylla paramamosain, probiotic, disease resistance, immune response
*Corresponding author
Address: 1, Shuefu Road, Neipu, Pingtung Taiwan, R.O.C.
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E-mail: [email protected]