Dietary supplementation of Lactobacillus sp. and garlic extract on growth performance, digestive enzyme, and disease resistance of the whiteleg shrimp, Litopenaeus vannamei

In the present study, the effects of a probiotic (Lactobacillus sp.), a prebiotic (1% garlic extract), and their combination were evaluated in whiteleg shrimp (Litopenaeus vannamei) using a feeding supplement. The shrimp in each tank were fed the following experimental diets for 56 days: the control diet (commercial feed) and experimental diets supplemented with Lactobacillus sp. (diet 1), garlic extract (diet 2), and Lactobacillus sp. + garlic extract (diet 3). The results showed that shrimp fed diets 1, 2, and 3 had higher growth indices, including weight gain, specific growth rate, and daily weight gain. The supplemented diet 3 recorded the lowest FCR and the highest shrimp survival rate after 56 days of feeding. In addition, the activities of amylase, protease, and aminopeptidase were significantly increased in shrimp fed the experimental diet relative to the control diet from day 28 until the end of the experiment. The overall bacterial count of Vibrio was significantly lower in diets 1, 2, and 3 than in the control diet at day 56. Moreover, shrimp fed diet 3 had the lowest cumulative mortality after 96 h post-challenge with Vibrio parahaemolyticus. Overall, the findings demonstrated that the addition of synbiotics containing 10⁸ CFU/kg Lactobacillus sp. and 1% garlic extract could promote growth, survival, and disease resistance in whiteleg shrimp reared under tank conditions.