DIETARY EXTRACTION OF ATRACTYLODES MACROCEPHALA KOIDZ ON GROWTH PERFORMANCE, HEALTH AND DISEASE RESISTANCE OF MACROBRACHIUM NIPPONENSE

Despite the rapid development of Macrobrachium nipponense, disease problems have become increasingly serious in intensive farming, resulting in lower production. Atractylodes macrocephala Koidz, which has anti-pathogenic and anti-vira effects, is not easily resistant to drugs, and has the ability to promote the animal growth and improve immunity. In order to better improve the growth performance and disease resistance of aquaculture animals, it is necessary to develop herbal-based feed additives in the aquatic products. Taking Macrobrachium nipponense as the research object, we explores the effects of extraction of Atractylodes macrocephala Koidz (EAMK) as herbal additives on growth, health and disease resistance, and provides a scientific basis for the development and application of aquatic green feed additives. In this paper, we investigated the effects of feeding different levels of EAMK on production performance, organ index, blood biochemical index, antioxidant capacity, digestive health and disease resistance of Macrobrachium nipponense. The experiment was conducted on Macrobrachium nipponense with an initial body weight of 0.21 g for 75d with six feed treatments. which were set up with the addition of EAMK at 0, 100, 200, 400, 600 and 1200 mg/kg (Control, A100, A200, A400, A600 and A1200). Each treatment had 6 replicates with 60 shrimp in each tank. During the experiment, feeding status of the shrimp was observed daily, and water temperature, pH, and ammonia nitrogen concentration were recorded. At the end of the experiment, serum, intestine, hepatopancreas were collected. The results showed that the addition of 200 mg/kg of EAMK significantly increased the weight gain rate (WGR) and specific growth rate (SGR) of Macrobrachium nipponense and reduced the feed coefficient (P<0.05). There were no significant differences in hepatopancreas index, meat percentage and body composition between the treatment groups (P>0.05). The serum glucose content of the A100 group was significantly higher than that of the control group (P<0.05), and the ALT content (P<0.05) was significantly reduced. Hepatopancreatic glutathione peroxidase (GSH-Px) activity was significantly higher in the A400 group than that in the A100 and control groups (P<0.05), hepatopancreatic catalase (CAT) activity was significantly higher in the A600 group than that in all other groups (P<0.05), and intestinal inducible nitric oxide synthase (iNOS) activity was significantly higher in the A200 and 400 groups than that in the control group (P<0.05). The intestinal villi of Macrobrachium nipponense in the A400 group were significantly higher than control group (P<0.05), which reduced vacuolation of hepatocytes and promoted gill integrity. The survival rate of Aeromonas hydrophila after attack in the A100 treatment group was significantly higher than that in the control group (P<0.05). In summary, the addition of 100—400 mg/kg of EAMK could promote the growth performance and antioxidant capacity of Macrobrachium nipponense and significantly improve the disease resistance.