author(s)
A Srinivasa Rao, D Ravindra Kumar Reddy, TV Ramana, A Chandrasekhara Rao, K Dhanapal, T Suguna, A Panigrahi, Rashmi Ranjan Das, G Ganesh and D Pamanna

abstract
In the present study the Ashwagandha (Withania somnifera) root extract was incorporated in the formulated diet at the levels of 0.05%, 0.1% and 0.15% to understand its effect on growth and digestive enzyme activities in Litopenaeus vananmei. The experiment was carried out for a period of 91 days under laboratory conditions with triplicate. The control and experimental diets were prepared to have almost similar crude protein level of 35% using the ingredients such as fish meal, shrimp meal, soya meal, deoiled rice bran, ground nut oil cake as major ingredients. Uniform water salinity of 15 ppt was maintained in the control as well as the experimental tanks. A significant improvement (P<0.05) in growth performance (weight gain, specific growth rate, feed conversion ratio and protein efficiency ratio) and elevation in activities of digestive enzymes (protease, amylase and lipase) were recorded in L. vannamei fed with Ahwagandha (Withania somnifera) incorporated diet compared to those of control. The treatment containing diet with Ashwagandha @ 0.05% was found significantly superior among all the treatments. The results indicated that inclusion of Ashwagandha in L. vannamei diets can enhance the growth parameters and activities of digestive enzymes.