Feed Formulation and Processing Techniques for Medicinal Silkworm Larvae Infected with Beauveria bassiana

Currently, medicinal silkworm larvae infected with Beauveria bassiana are in strong demand on the Chinese medicinal herb market, and raising and processing them is profitable.

The methods for raising and processing them are:

1. Rearing the mature silkworms.

Raising and processing medicinal silkworm larvae infected with Beauveria bassiana should be carried out as a specialized operation in non-cocoon-producing areas, so as to avoid a devastating impact on cocoon silkworms. The raising and processing can be carried out throughout the year. As for the feed, besides a small amount of mulberry leaves, more evening primrose, Jiancan grass, white clover, cup plant (Silphium perfoliatum) and the like can be added to replace mulberry leaves, so as to supplement the shortage of mulberry leaves and reduce feeding costs. The rearing and management techniques for mature silkworms are the same as conventional @#@250@#@, and they need to be raised until the fourth molt.

2. Preparing the fungal culture.

Take 50 empty 500 mL infusion bottles, fill them with cooled boiled water, and inoculate one test-tube stock culture of Beauveria bassiana into 10 of the bottles; after letting them stand for 1 hour, use them as stock cultures, then inoculate each bottle of stock culture into 5 bottles respectively, thus preparing a liquid fungal culture. If no test-tube stock culture is available, naturally infected stiff silkworm larvae can be washed with cooled boiled water, and the cooled boiled water after washing can also be used as a liquid fungal culture.

3. Spray inoculation.

After the mature silkworms molt for the fourth time, shed their skins and revive, use a sprayer to evenly spray the liquid fungal culture onto the silkworms' bodies, until the skin is wet. If the fungal strain has poor viability, inoculation must be completed within 1 hour after the liquid fungal culture is prepared.

4. Strengthen management.

15-20 minutes after inoculation with the fungal culture, begin feeding grass, once every 5-6 hours. Keep the indoor temperature at 20-30°C and the humidity above 90%, and strictly avoid ventilation. Generally, 20-24 hours after inoculation with the fungal culture, the silkworms begin to lose their appetite, behave sluggishly, and their body surface gradually turns greenish-brown with black spots of various shapes; by the 3rd-4th day, they begin to die; by the 5th-6th day, the death toll reaches 70%; by the 7th-8th day, all have died.

During the process of the silkworms dying, promptly pick out the dead silkworms and spread them in the rearing room, maintaining the same temperature and humidity, and let them fully stiffen, so as to increase the finished product rate and the content of medicinal agents. Once all meet the requirements for stiff silkworm larvae, they can be sold on the Chinese medicinal herb market.