How to Raise Ground Beetles? A Detailed Guide to Breeding Management and Ootheca Hatching Techniques

Breeding Management Techniques

I. Rearing Methods

They can be kept in jars or basins, or in ponds. The temperature in the rearing room should always be maintained at around 30°C, so they can be marketed in 9 months; if reared outdoors at natural temperatures, it takes about 30 months to reach market size.

II. Breeding Management

1. Preparation of rearing soil. Mix 30% field loam with 70% fermented sawdust, then sun-expose the mixture for sterilization. Alternatively, mix 30% plant ash with 70% field soil, then sun-expose for sterilization.

2. Temperature and humidity. Suitable temperature and humidity for ground beetle growth: indoor temperature 30°C-32°C, humidity 70%-80%, rearing soil temperature 28°C-30°C, humidity 15%-20%.

3. Feed.  A. Concentrated feed. Plant-based feeds include grain, oilseed meal, rice bran, wheat bran, etc.; animal-based feeds include fish meal, silkworm pupa meal, bone meal, etc. B. Green feed. Includes various vegetables, fresh tender wild vegetables, tender pasture grass, tender tree leaves, tender crop leaves, etc. C. Succulent feed. Includes melons, fruits, pears, peaches, carrots, white radishes, potatoes and other feeds with relatively high water content. Reference feed formula: corn (2315, -8.00, -0.34%) meal 50%, wheat bran 25%, soybean meal powder 10%, bone meal 5%, fish meal 2%, vegetable leaf powder 8%.

4. Management. A. Environmental control. The air in the rearing room should be fresh; when heating for rearing in winter, open windows frequently for ventilation, but the temperature difference should not exceed 5°C. Rearing soil thickness: 7-15 cm during the nymph stage, 20-25 cm during the adult stage. Rearing soil humidity is 15%-18%. B. Rearing density per square meter. When sesame-sized: 80,000-200,000; when mung bean-sized: 80,000-100,000; when soybean-sized: 30,000-40,000; when broad bean-sized: 14,000-20,000; adults: 8,000-10,000; egg-laying females: 4,000-5,000.

III. Harvesting and Primary Processing

Males mature earlier. When their wing buds have just grown out, carry out a selection: pick out those with large bodies and good color and keep them for breeding; scald the surplus with boiling water, then sun-dry them for medicinal use. After females molt 9-11 times, sieve them all out, select those with large bodies and good color for breeding, and kill and sun-dry the surplus. Note: do not harvest on cloudy days.

Prevention and Treatment of Ootheca Mold Rot

Cause Caused by fungi. Because the container storing the oothecae is not clean, mold grows when humidity is too high, causing the oothecae to become moldy.

Symptoms Moldy oothecae exude a white liquid; under a magnifying glass, white mold filaments can be seen, and the moldy oothecae have a foul odor.

Prevention and Treatment

I. The collected rearing soil must be sun-exposed for sterilization before use.

II. Collect oothecae once every 5-7 days. After collection, remove impurities, wash, and air-dry them. Then take 1 part of 3% bleaching powder and 9 parts lime powder, wrap them in gauze, sprinkle over the oothecae, sieve off the powder after 30 minutes, and store the oothecae properly. How to prevent and treat green mold disease

Cause Environmental humidity is too high, green mold reproduces rapidly, and ground beetles are infected by green mold.

Symptoms The abdomen of infected ground beetles is dark green with spots; the limbs contract, the antennae droop, and they do not come out of the soil to eat. Prevention When air humidity is high, the rearing soil should be on the dry side, and the feed should have a lower water content; remove leftover feed frequently, and wash and disinfect feed trays regularly.

Treatment Pick out the infected ground beetles and disinfect their bodies with 0.5% formalin; sieve out the healthy insects from the affected rearing pond and disinfect the pond with 3% formalin; mix antibiotics into the feed given to diseased ground beetles, adding 1 g of chlortetracycline or oxytetracycline powder per kilogram of feed.

Prevention and Treatment of Bloating Disease

Cause In early spring and late autumn, after ground beetles eat a large amount of food, the temperature suddenly drops, their metabolic capacity declines, and indigestion results. Symptoms The abdomen of infected ground beetles becomes swollen, crawling is difficult, appetite decreases or is lost entirely, diarrhea occurs, feces are green, and the body loses its luster.

Prevention When the temperature drops suddenly, increase heating. The amount of food given should be adjusted according to weather changes: give more when the temperature is high and less when it is low. On rainy days, feed less green feed; when the temperature is low, add 0.02% oxytetracycline or sulfaguanidine to the ground beetle feed.

Treatment For affected ground beetle colonies, feed them with 2 tablets of pepsin, 2 tablets of berberine, and 2 tablets of rhubarb soda added per kilogram of feed.

Reproductive Characteristics and Ootheca Hatching Techniques

The ground beetle is an insect with incomplete metamorphosis. Its life goes through 3 stages: egg, nymph, and adult, one pupal stage fewer than insects with complete metamorphosis. Each time a nymph molts, its instar increases by 1, its body weight and body length increase by one grade, and reproductive growth and development advance by one stage. Males go through 7-9 molts and mature after 270-320 days; female nymphs go through 9-11 molts and mature after 450-500 days.

Ground beetles reproduce sexually and are oviparous. One male ground beetle can mate with 3-5 females in its lifetime; after mating, the male's wings break off, and it dies successively about 1 month later. Females begin laying eggs about 7 days after mating. The peak mating period is summer and autumn, with the highest mating rate at 25°C-32°C. During the mating season, males account for 40% of the total adults. At natural temperatures, the egg-laying period is from May to October, with the peak from June to September. One healthy female adult produces 70-100 oothecae in her lifetime. The hatching rate of oothecae is related to storage time and temperature; a long storage time and high storage temperature result in a low hatching rate. Oothecae stored at 12°C-15°C for 4 months can still hatch nymphs, but they cannot be stored long-term at temperatures above 20°C.

Hatching containers can be plastic basins, wooden basins, plastic buckets, etc., and should be disinfected with a 0.2% potassium permanganate solution before use. The hatching soil is made by mixing 30% field loam and 70% sawdust; the sawdust must come from fermented broadleaf trees. Before use, first sun-expose the hatching soil for more than 3 days to kill insect eggs, mold, etc., then spray and disinfect it with a 0.1% potassium permanganate solution, with humidity at about 20%, that is, it can be formed into a ball when squeezed in the hand and disperses when the hand is released; soak the oothecae in a 0.2% potassium permanganate solution for 3-5 minutes. Then, mix the oothecae with the hatching soil at a ratio of 1:1, place them in the container, and cover with 4 layers of wet gauze. Soak the wet gauze in water in time and remove excess water to facilitate ventilation. After the hatching soil dries, sieve out the oothecae, sprinkle water on the hatching soil, mix well, then mix it with the oothecae again and cover with wet gauze. Keep the hatching room temperature at around 30°C, the hatching soil humidity at around 20%, and the indoor relative humidity at 70%-80%; after about 40 days, nymphs can hatch.