Feed additive enzymes Simple classification of feed enzymes:
1.endogenous enzymes, refers to the animal body can secrete digestive enzymes, the main function is to digest the nutrients in the feed used to improve the digestibility of feed; The digestive system of young animals is not perfect, and the digestive enzymes secreted by the body are insufficient. In particular, a large amount of endogenous enzymes should be added to the feed based on plant raw materials to solve the digestive problems. Endogenous enzymes generally refer to protease, amylase, lipase and so on.
2. Exogenous enzymes refer to the enzyme preparations that animals cannot secrete autonomously and must be added. The main function is to degrade the anti-nutrient factors of plant raw materials, non-starch polysaccharides that hinder the release of nutrients and react with the contact of endogenous enzymes, such as cell walls, and non-starch polysaccharides that bring negative effects; Common are phytase, xylanase, glucanase, cellulase, mannanase, galactosidase, etc.
3.functional enzymes, mainly use its catalytic function to achieve the processes and products we need, such as glucose oxidase, a brief overview is the catalytic process with glucose to consume oxygen, produce gluconic acid and hydrogen peroxide, Reduce the PH value of the gut, and use its strong oxidation to alleviate mycotoxin poisoning and protect the health of the digestive system, improve immunity and other functions; In addition, there are catalase, lysozyme and other related products, the specific function is not this unnecessary
feed additive enzymes,poultry feed enzymes,feed grade enzymes,animal feed enzymes ,feed enzymes NANYANG CHENGPENG PHARMACEUTICAL CO.,LTD , https://www.chppharm.com
The production technology of big bunting fish fry
The broodstock can be selected either naturally or through artificial means. The breeding season typically runs from May to September, with the peak occurring between May and June. Female broodstock should ideally weigh around 25 grams, and second-instar fish tend to produce more eggs. A well-developed sex gland in females is indicated by a noticeably enlarged abdomen, full-looking breasts, and a rounded, blunt belly. Male fish should be selected to weigh approximately 20 grams, with a longer mastoid (the bony projection behind the eye) that extends beyond the tip of the snout.
Broodstock with fully developed gonads can be used directly for spawning or placed in spawning pools or pipelines. Those with a gonad maturity level of 3 to 4 months are kept in holding pools and fed benthic diatoms collected from natural beaches. The pool depth should be between 20 and 30 cm, with 50% of the water replaced daily to maintain optimal conditions.
Artificial hormone induction often uses human chorionic gonadotropin (HCG) and luteinizing hormone-releasing hormone analog (LHRH-A), either alone or in combination. These hormones are administered via injection into the base of the pectoral or dorsal fin. Females receive two injections, spaced 16 to 24 hours apart, while males receive a single dose, at half the concentration per gram of body weight compared to females.
At a water temperature of 22–24°C and salinity of 25–27‰, eggs mature within 24 hours after the second injection. High doses of HCG or a combination of HCG and LHRH-A show the best results in inducing ovulation. Males are injected once and synchronized with the female’s second injection. After spawning, the fish are separated into male and female groups, with daily water changes and inflation. At 19–21°C, the effect lasts 39–58 hours, while at 26–29°C, it takes only 14–16 hours. Within 12 hours post-injection, females are checked regularly for egg development. If mature eggs are observed, the male’s testes are collected and dried for artificial insemination.
The process involves dissecting the ovary, cutting the ovarian sac into a dry plastic container, or extruding the eggs without dissection. Male gonads are then cut or crushed and mixed with the eggs in a 2:1 ratio of female to male. The fertilized eggs are then transferred into a bucket of clean seawater, agitated evenly over a pre-prepared sieve, and hung in the hatching pond.
Artificial spawning pipes made of ceramic cylinders (10–20 cm in diameter) are placed in spawning tanks with a water depth of 20–25 cm. These pipes are removable and allow for easy egg collection. Broodstock with well-developed gonads are placed inside, and they are fed benthic diatoms daily. Spawning in these pipes typically occurs between midnight and dawn. Daily checks are conducted in the morning, inspecting 2–3 pipes at a time. If spawning is detected, all eggs are carefully moved to an incubation pool. Each batch can yield over 10,000 eggs, suitable for tuber production. While artificial pipelines encourage pairing and natural spawning, the process is not highly concentrated, so multiple small nursery ponds are recommended. Increasing the water temperature in the spawning pool has been shown to enhance gonad maturation and promote more concentrated spawning.
For incubation, hatched eggs or those collected from spawning pipelines are directly placed into cement hatchery pools or cages, both of which can achieve a high hatching rate of 50–60%. Water is changed daily by 50%, or a gentle flow is maintained throughout the day. The ideal incubation temperature ranges from 26–28°C, and should not exceed 30°C. Under conditions of 26.5–29.2°C and salinity of 25–27‰, fish larvae typically emerge after about 87 hours.
By the fourth day after hatching, most larvae have already broken free from their membranes. At this point, the egg nets and pipelines are removed. The hatched larvae can remain in the hatchery pond for further growth or be transferred to nursery ponds.
In the larval rearing phase, newly hatched larvae measure about 2.5 mm in length. Nursery ponds are stocked at a density of 5,000 fish per cubic meter. On the second day post-hatching, the larvae begin to open their mouths. By the fifth day, their total length reaches 3.5–4 mm, the yolk sac has disappeared, and they have one small oil globule left. They display 13 melanin spots on the ventral edge and start feeding on rotifers from the third day onward.
Rotifers are fed twice daily, with the quantity calculated based on current density. The recommended rotifer density in nursery ponds is around 5 per milliliter. Around day 35, metamorphosis begins, and the fish enter the larval stage. Their scales become more defined, and they develop 8 rows of horizontal melanin stripes along the sides and back. At this stage, Artemia nauplii should be introduced. From late juvenile to early juvenile stages, their diet shifts to animal-based food. When the young reach about 2 cm in length by day 45, they are transferred to mudflat areas where benthic diatoms are collected for feeding. At this point, they are ready to leave the nursery.
Throughout the nursery period, the water used is sand-filtered seawater, and the salinity is adjusted using fresh water if needed. The ideal salinity range is 1.010 to 1.015. Aeration increases gradually as the fish grow, and daily water changes range from 1/5 to 1/2 of the total volume.