Frog Farming Technology

Author: Chief Editor: Zeng Zhongping
Publisher:
Publish Date: 1999-09-01
Features: This book is compiled by Professor Zeng Zhongping from the Biology Department of Beijing Institute of Education. Since its publication in 1991, it has been printed 12 times and distributed over 200,000 copies, highly favored by readers. This revision, based on reader requests, primarily adds content on bullfrog disease prevention and control, bullfrog recipes, and 24 color photographs, making it more illustrative and easier for readers to read and apply. The book covers 7 chapters: Overview of Bullfrogs, Basic Biological Knowledge of Bullfrogs, Preparations for Bullfrog Farming, Rearing and Management of Bullfrogs, Bullfrog Diseases and Their Prevention, Transportation of Bullfrogs, Harvesting and Processing of Bullfrogs. It is suitable for bullfrog farmers, animal husbandry and aquaculture technicians, and students and teachers of relevant majors in agricultural schools for reference.
Excerpt: Bullfrog byproducts can be directly used as animal protein feed. From the perspective of their nutritional composition and content, they are high-quality feed for livestock, poultry, and fish. Experiments show that feeding egg-laying hens with bullfrog byproducts (adding 150 grams of fresh internal organs per hen daily) significantly increases egg production, with an average egg weight of over 60 grams per egg. After stopping the feeding for 3 days, egg production and weight decline noticeably. Adding bullfrog internal organs to pig feed results in an average weight gain of 0.9 kilograms per kilogram of fresh bullfrog internal organs added over 100 days. Bullfrog internal organs also yield satisfactory results when fed to animals such as sable, weasels, and fish. Dried bullfrog powder made from bullfrog byproducts can replace fish meal.
V. Insect Catchers Bullfrogs are large amphibious carnivorous animals skilled in swimming, hiding, and jumping on land (up to 1.5 meters high). They have strong abilities to catch insects. A single adult bullfrog can consume over 10,000 insects in a year, and each tadpole can eat over 100 mosquito larvae (bloodworms) daily. The insects bullfrogs prey on are mostly agricultural and sanitary pests, such as the sugarcane borer, rice borer, rice leaf folder, rice planthopper, rice bug, rice earwig, cutworm, grasshopper, mole cricket, loopers, beetles, weevils, click beetles, longhorn beetles, yellow ladybugs, termites, flies, maggots, and mosquitoes. They are known as the "big predators" of pests. Bullfrogs also eat earthworms, spiders, snails, clams, dragonfly larvae, etc.
VI. Other Uses Although bullfrogs have low fat content, the pair of fat bodies at the front of their gonads are rich in fat. Extracted bullfrog oil is an excellent lubricant for precision instruments in airplanes and rockets. Additionally, bullfrog oil is a high-quality animal fat with a low melting point, high content of low-molecular fatty acids, and essential fatty acids (such as oleic acid) that meet the average levels of vegetable oils (with an unsaturation degree of 85%). Its saponification value, peroxide value, and acid value are all low, indicating it can be used directly without refining. This not only holds high economic value in industrial processing but also significant biological and nutritional value, specifically:
① In the food industry, it is suitable for low-temperature storage and can serve as a special-flavored cold-pressed oil, as well as replace vegetable oils in the production of shortening, margarine, and cocoa butter due to its solid lipid plasticity.
② In the chemical industry, its high content of low-molecular fatty acids, which are easily absorbed by the skin and soluble in water, along with its low saponification value and low soap-forming properties, make it widely applicable in cosmetics manufacturing.
③ In medical and health care, essential fatty acids are the main raw materials for physiological activities such as the growth and development, reproduction, and synthesis of phospholipids, the growth of new tissues, the repair of injured tissues, and the production of prostaglandins. They also play a role in preventing and treating hepatitis, arteriosclerosis, and hypertension, as well as lowering blood lipids. Additionally, bullfrog oil is rich in vitamins A and E, with vitamin A levels 15 times higher than those in sable oil. All these attributes make it highly valuable in medical and nutritional applications.
Bullfrogs have well-developed endocrine glands, including the pituitary gland and gonads, which secrete various hormones. The pituitary gland alone can secrete 10 types of hormones. Hormones extracted from these glands have broad applications in medicine and production. For example, a saline suspension (0.7%) of bullfrog pituitary gland can promote egg production in sexually mature fish and amphibians when injected subcutaneously or into fins at appropriate doses. Due to their large size and ease of artificial breeding, bullfrogs have become ideal experimental materials for teaching and research. They have been sent into space for disease experiments aboard spacecraft and are widely used in hospitals for pregnancy tests.
In summary, bullfrogs are truly treasures in every aspect. With the advancement of science and technology, their uses will undoubtedly expand further, and the level of comprehensive utilization and deep processing will continue to improve.