The invention discloses a medicinal
plant extract for improving the anti-stress capability of
micropterus salmoides as well as a preparation method and application of the medicinal
plant extract. Belongs to the technical field of
aquaculture. The
rosemary extract is prepared from rosemary,
astragalus membranaceus and liquorice according to a specific proportion through an innovative process of composite enzymolysis, ultrasonic-assisted extraction and
macroporous resin purification, and can effectively relieve temperature,
water quality and transportation stress; the resistance of the
micropterus salmoides to novel stress sources such as low-
oxygen stress and
salinity sudden change can be obviously improved. Experiments prove that the extract can significantly reduce serum cortisol and
lactic acid levels and improve
superoxide dismutase activity and immunoglobulin concentration under the addition amount of 0.1%, the
survival rate under hypoxia stress is improved by 35% or above, the regulation
recovery time under
salinity sudden stress is shortened by 50%, and the content of the
superoxide dismutase is reduced by 50% or above. The obvious synergistic interaction effect and the unexpected technical effect are shown.