Goldfish: Characteristics, Classification, Farming and much more

 Goldfish

Goldfish, (Carassius auratus), ornamental aquarium, and lake fish of the carp family (Cyprinidae) originated in East Asia but were introduced to many other areas. Goldfish resemble carp (Cyprinus carpio) but differ from their relative in that they have no barbels. Chinese homes were made at least early in the Sung dynasty (960-1279).

Goldfish are naturally green or gray. Species, however, vary, and many unusual occurrences occur. The divergent fish may be black, transparent, gold, white, or white with silver; it may have a severed tail or protruding eyes, or it may not have a normal dorsal fin.

Over the centuries the selection and production of these rare species have produced more than 125 species of goldfish, including the common-tailed star, of domestic animals; veil tail, three-stranded, flowing tail; lion's head, with a swollen "hood" on his head; and celestial, with eyes out, pointed upwards.

Goldfish eat omnivorously, eating plants and small animals. In captivity, it works well on small crustaceans and food can be supplemented with chopped mosquito larvae, grains, and other foods.

Breeding occurs in spring or summer. As the season draws to a close, the colors become brighter, the woman's abdomen grows larger, and the male can grow to have a head-sized cover on the gill, back, and pectoral fins.

The eggs attach to the water plants until they hatch about a week later. Pet goldfish are known to live 25 years; life expectancy, however, is very short.

Fleeing from park ponds and gardens, goldfish have become commonplace in many parts of the eastern United States. When it resumes wildlife, it returns to its original color and can grow from an aquarium size of about 5-10 inches (2-4 inches) to a height of up to 30 inches.

 Cyps are evolved from wild red-yellow crucian carp.  Goldfish is one of the world's three most famous ornamental fish. It originated in China and has a history of more than 1700 years.

Goldfish holds a very important position in the commercialization of ornamental fish in many countries. Goldfish has a beautiful body and a wide variety of colors. "Five independent species of fish, fish are gold grass, red dragon eye, crane top red, blisters and black life.", etc., and its body shapes include lion head, tall head, blisters, dragon eyes, pompons, and pearls. Scales, butterfly tails, tiger heads, etc.  

The five representative species of goldfish are grass gold, red dragon eye, crane top red, blisters, and black life.

Settlement of origin

"Goldfish are ornamental fish species from wild carpians.". "China has become the first country to farm goldfish". Crucian carp naturally has a gray belly and a white belly, which makes it easier to avoid predators in natural waters."

Sometimes, the pigment cells of carpians carp change into fish that turn golden yellow.". If there is no human intervention, such a changeable person will be eaten by the enemy because it is easy to disclose the goal." 

Goldfish originated in China. It is documented that when Jinhuan rushed to Lushan Mountain, there were red-skinned fish in the lake. This red-skinned crucian carp was the earliest ancestor of goldfish. Therefore, it can be considered that goldfish was first discovered in China during Jin Dynasty (between 265-420 AD). 

Chinese scientists have made significant contributions to the preservation and breeding of goldfish."

Goldfish were introduced to Japan in 1502, and after World War II, Japan introduced many species through Taiwan.". Goldfish were introduced to Britain in the late 17th century, imported into Europe in the 18th century, and to the United States in 1874, and then spread around the world.". 

Chinese scholar Chen Zhen summarized its evolution into four stages: ① the wild state of red and yellow crucian carp to the stage of semi-domesticated state; ② the pond culture stage-the beginning of goldfish domestication; ③ the pot culture stage; ④ the conscious artificial selection stage. It is not difficult to see that goldfish evolved from wild crucian carp through long-term natural mutation, artificial selection, hybridization, and other factors. There are hundreds of species of goldfish.  

Morphological characteristics

Goldfish belong to the same species as crucian carp in taxonomy. Compared with crucian carp, goldfish have a huge variation in external morphology, but in general, the whole fish body can be divided into three parts: head, trunk, and tail. The foremost part of the head is the mouth, and the back is the nose, eyes, and operculum. 

Some breeds have sarcoma on the upper end of the head, some breeds have pompoms above the nose, some breeds have protruding eyes, are positioned upward or have blisters, and some breeds have operculum leaking to form gills. 

The torso of the goldfish is covered with scales, and there are mainly normal scales, transparent scales, and pearl scales. There are lateral lines on the side, and the number of lateral line scales, under lateral line scales, and lateral line scales of different species of goldfish are not the same. 

The trunk of a typical goldfish has pectoral, pelvic, anal, dorsal, and caudal fins, and individual species have no dorsal or anal fins. The tail of a goldfish is composed of a caudal stalk and a caudal fin, and the shape of the caudal fin varies widely.  

The male goldfish entering the breeding period will have white chasers on the edge of the gill cover and pectoral fins. This is the most accurate time to distinguish the sex of the goldfish. Another important difference between male and female goldfish is the cloacae. Generally, males are small, narrow, and concave; females are large, slightly rounded, and convex.  

Variation in external form

The body of a goldfish is composed of three parts: head, trunk (carcass) and tail, and the dividing line between each part is not obvious. Usually from the snout end of the body to the back edge of the operculum, a line perpendicular to the beginning of the pectoral fin is called the head; from the posterior edge of the operculum to the beginning of the anus or anal fin is called the trunk; from the anus or anal fin The trailing edge of the scale to the posterior side of the lateral line is called the tail.  

The ancestor of goldfish is wild crucian carp. However, from the perspective of external morphology, it is very different from crucian carp, and there is almost no single trait that has not changed. The introduction is as follows:  

Body type variation

Goldfish are silver-gray, red, yellow, white, black, purple, blue, transparent, variegated, and five-flowered. The color of wild crucian carp is dull and unsharp. And domestic goldfish have many bright colors. On the surface, it seems that a lot of new pigments have occurred during the process of homemaking in goldfish.

 In fact, it is not the case. From the microscope observation of the scales, the pigments that are present in the brightly colored goldfish are also present in the wild crucian carp that is not brightly colored. There are only three color components of goldfish: black pigment cells, orange-yellow pigment cells, and light blue reflective tissue, all of which are present in wild crucian carp. 

The bright and changeable body color of domestic goldfish is only due to the recombination, redistribution, changes in strength and density of these three components, or the disappearance of one or more of the original pigments of wild crucian carp. 

During the ontogeny of goldfish, there was a phenomenon of fading. Black goldfish, such as ink dragon eyes, ink bubbles, etc., change with age. Some snakeheads fade to orange-red or red-black within 2-3 years, some fade to black and white, and some remain black for a long time. There are very few permanently black goldfish. 

All species of goldfish are grayish-brown at the juvenile stage. After a certain period of development, the pigment cells disappear and turn into the body color of the fish. Only the difference between purple, transparent and five-flowered goldfish is earlier than other goldfish, which can be distinguished by the naked eye after body shape differentiation.  

Body shape variation

The body shape of wild crucian carp is oblong and flat. Domestic goldfish are shorter in size and rounded on both sides. The mode of the ratio of the body length to the head length of a goldfish is 2.4, while that of a crucian carp is 3.5. 

This shows that goldfish are short-bodied, while crucian carp are long-bodied. The ratio of body height to head length is the same for goldfish and crucian carp, both are 1.2. This shows that goldfish and crucian carp have the same body height in terms of the ratio of head length. The height of the goldfish seems to be higher than that of the crucial, but it is actually due to the shortened body length.  

Variation in the number of scales

The number of scales on the lateral line of domestic goldfish can be as few as 22 and as many as 28. The variation range of wild crucian carp is 28-32 pieces. The mode of lateral scales of domestic goldfish is 26, while that of crucian carp is 29. This is obviously related to body length. 

After the scales fall off due to trauma, they can regenerate, but the shape, size, and location of the regenerated scales are different from the original scales, which affects viewing. Keeping goldfish should try to avoid the scales from falling off.  

Variation of the dorsal fin

There are two kinds of the normal dorsal fin and no dorsal fin (dragon back). All wild crucian carp and most domestic goldfish species have normal fins; a few species have their dorsal fins disappeared, completely without dorsal fins, and their backs are round and smooth. 

There are also some stumps, short backs, and some protrusions on the back, but these variations are not liked by breeders and are usually eliminated at the juvenile stage.  

Variations of pectoral fins

Pairs of pectoral fins are located behind the breast and gill openings of the goldfish, short and long. The mode of the ratio of the distance from the snout to the pectoral fin to the head length, the mode of both domestic goldfish and wild crucian carp is 1.0. The author has observed a tail with double pectoral fins, which is very rare.  

Variation of pelvic fin

Pairs of pelvic fins are located at the bottom of the ventral surface of the goldfish, and there are short and long ones. The ratio of the distance from the snout to the pelvic fin to the head length is 1.6 for domestic goldfish and 1.7 for wild crucian carp.  

Variations of anal fins

The anal fin of goldfish is located near the back of the anus. All wild crucian carp have a single anal fin, while domestic goldfish have a single butt, double buttock, single buttock (3 buttocks), residual buttock, and no anal fin. The distance from the snout to the anal fin, the ratio of the head length, is 2.1 for domestic goldfish and 2.7 for wild crucian carp. 

From the results of the distance between the snout end to the pelvic fin and the snout end to the anal fin, it is obviously related to the body length. It can be seen that the shortening of the body length of domestic goldfish starts from the pelvic fins and reaches the hips most significantly.  

Variation of caudal fin

Goldfish have a single tail, double tail, upper single and lower double (3 tails), vertical tail, unfolded tail (fantail, butterfly tail spreading fins and upwards, long tail, medium-long tail, short tail and stump tail, etc.). 

There are also many variations in the color of the caudal fin. Some caudal fins have the same color as their body colors; some are red and white; some species have red tail fins with white edges, some red tail fins have black edges; some species have red tail fins with black edges. Patches of different colors, such as various five-flowered varieties belong to this category.  

Head shape variation

Breeders across the world divide the head type into tiger head, lion head, goose head, tall head, hat, and toad head. Among these head types, some are of the same type and have different names in different places. 

For example, what is called tiger head by Beijing breeders are called lion heads in Nanjing. It is called a hat in Beijing, and a tall head or goose head in the south. The author agrees with Chen Zhen's naming and distinguishes the head shape into three types: flat head, goose head, and lion head.  

Life habits

Goldfish have a mild temperament and generally have a life span of about 6 years, although some are longer. Goldfish is a kind of omnivorous and partial carnivorous freshwater fish, with developed throat teeth, which can swallow harder bait. Goldfish have strong adaptability to water temperature but cannot adapt to drastic changes in temperature.

The suitable water temperature is 18-26°C. Too high or too low temperature will affect the feeding, growth, and reproduction of goldfish. Goldfish like slightly alkaline water and the pH value of the water body is more appropriate at 7.5-8.0. When the water temperature began to rise during the transition of spring and summer in northern my country, goldfish also entered the breeding period. Controlling the water temperature at about 20°C during this period is more conducive to the spawning and hatching of goldfish.

Variety & Classification

The classification of goldfish is more diverse. According to the traditional classification, it is roughly divided into grass goldfish, dorsal fin, and no dorsal fin. Among them, grass goldfish is the most common color crucian carp in the fish market; dorsal fins are divided into literary species and dragon species, and the representative species are lions head and dragon eye; without dorsal fins are divided into egg species and dragon back, and the representative species are orchids. 

Goldfish include "Dragon Eye" and "Egg Fish". " Dragon Eye " is the most common two-tailed goldfish, looking down from the back of the fish, as the word "Wen". "Dragon Eye" has a further variation, with protruding eyes. The variation of the "egg fish" is more obvious, the body shape is completely different from the streamlined shape of the wild state, and becomes an oval shape. 

The dorsal fin of the fish is also degraded. Another further variation is that the fish head gives birth to fat, commonly known as "lion head". "Goldfish Breeding Method" introduced the basic types of goldfish and "lion head" as follows: 

Dragon eye fish: "Dragon eye fish, this kind of black is as black as ink, and the one that remains unchanged until the length of the length is the upper one. It is called the ink dragon eye. There is also pure white, pure red, pure emerald, and large safflowers, finely broken red. Pointers, tiger skins, red-white-green-black flowers, many kinds of changes, cannot be described in detail.

Literati always named their suits and colors. The body is always thick and uniform, the tail is big and upright, and the body is positive. The round, round and smooth mouth, it rises and falls in the water and swims steadily and smoothly, without pitching and running, making the viewer feel at ease. It is top-grade. There is also an egg dragon eye, which is also a kind of egg fish."  

Egg fish and lion head: "Egg fish, this kind of ridgeless spines, round like a duck. Its color is variegated, all like a dragon, but it has no ink color, and its eyes are not protruding. The head and tail of the figure areas before. And there is a kind of raw meat on the head, which refers to the thick remaining, causing the eyes to sink.

It is especially popular among players. It is pure white and the first flesh is red. The name Lionhead fish: the older the head, the taller the flesh. There is a thorn on the back or a bubble-like gold, because it is strung by a fish, and it is not expensive."  

The color and variegation are the same as before, and there is no black. The head and tail of the body are like dragon eyes, and only two eyes are not protruding. It can also give birth to a lion's head over time. It has a ridge. The short thorn, the lack, and the unconnected are the ears of the egg fish."  

In short, name it arbitrarily, and there is never a person who has a face." Others think that the color change is related to the feeding or growth stage: "To the bright color, it is all in the breeding method. The dragon eye fish is black when it comes out, and the egg fish is almost black and slightly lighter when it comes out. It is full of red, black, and red, red and white, broken flowers, and whole flowers. Among them, the color cannot be changed, and it is the method of raising. If one fails, the color of flesh red and white flesh will often appear."  

Distribution range

From a global perspective, goldfish farming is mainly concentrated in Asia. Thailand and Japan have the largest farming scale and the widest impact. In addition, Indonesia, Malaysia, and Singapore are all distributed.  

At present in China, all provinces except Tibet have goldfish farms or ornamental fish trading markets. The four major producing areas of domestic goldfish are mainly Fuzhou City, Beijing-Tianjin The region, Suzhou-Hangzhou Region, and Guangzhou City. Among them, Fuzhou City ranks first.

In 2017, Fuzhou City had nearly 60 goldfish farms with an area of ​​133hm ² and more than 80 strains. It is known as the "Goldfish Capital of China".  

Reproduction

The shape selection of broodstock generally includes five aspects: shape, dynamics, color, health, and specifications. The standard for morphological characteristics of broodstock should be pure and excellent strains, with obvious characteristics, uniform body, and standard body shape and tail shape.  

The color standard is: the color should be full-bodied and vivid. Monochromatic fish should be pure and flawless; redfish should be red from head to tail like fire; cuttlefish should be black and shiny; two-color fish should be alternately colored and not chaotic; crane top red and silvery-white all over, sarcoma on the top of the head straight, red like a bun flower. Choose a broodstock that is sturdy, free from injury, disease, mildew, complete scales, and no scaling phenomenon.  

(1) By selecting 1-2-year-old male fish and 2-4 year-old female fish, new male, and old female broodstock adopt the method of male and female separate culture, reasonable stocking density, and strengthen the feeding of high protein feed and animal and plant food to maintain Appropriate water temperature, sufficient light, and maintaining a freshwater environment, while strengthening the prevention of broodstock diseases, and strengthening broodstock prenatal cultivation is beneficial to increase the amount of goldfish conceiving eggs.  

(2) In the reproduction process, adopting a combination of males with a female-male ratio of 1:1~3 more than females and adopting distant mating as much as possible can increase the fertilization rate of goldfish; at the same time, choose sunny weather. In a suitable fish nest, water flushing stimulation and other methods can increase the amount of goldfish spawning.  

(3) The natural breeding method of goldfish is the easiest to operate, and it is easy to implement in mass breeding production, and can avoid the broodstock from being injured by artificial reproduction, and greatly reduce the postpartum mortality of broodstock. 

The method of artificial reproduction is relatively complicated and the workload is large, but the number of eggs laid is significantly higher than that of natural reproduction.

Among the three artificial insemination methods of artificial reproduction, the wet insemination method can minimize the damage of the broodstock, and the fertilization rate is higher.

The fertilization rate of artificial gynogenesis is relatively low. At this stage, artificial gynogenesis is in the stage of research and experimentation, but the offspring obtained from it can obtain the excellent traits of the genetic mother, with high purity, and good development prospects.

Goldfish fry can reach sexual maturity after one year of cultivation. Goldfish is a kind of temperature-changing animal, and its breeding time is directly affected by water temperature. The breeding seasons of goldfish are different in the north and south of our country. In the south, the breeding season usually enters from March to April each year.

1.      Female and male identification of goldfish: Before sexual maturity, the difference between the female and male appearance of goldfish is very small. In the breeding season, the male-female appearance is gradually obvious.

2.      The first fin of the male ventral fin and the operculum have milky white "star chaser". The genital pores are small and narrow, slightly concave inward; while the female fish feels soft when touching the above parts with their hands, without "chasing stars", and the genital pores are slightly convex outwards.

3.     Preparations before breeding. The spawning pool or tank is preferably 1 to 2 square meters and the water depth is 20 to 25 cm. It can hold 6 to 8 pairs of broodstock. Household goldfish can also, be raised in enamel or plastic basins, and 1 to 2 pairs of broodstock can be placed.

4.     Goldfish eggs are sticky eggs, and there must be attachments when laying eggs, commonly known as "fish nests", so that the eggs adhere to them and facilitate hatching. Families can use Ceratophyllum, Hydrilla verticillata, etc., just put 1 to 2 plants for each pair of broodstock.

3. The reproduction of goldfish. There are two breeding methods for goldfish: natural breeding and artificial breeding. The family adopts natural breeding more. 

Generally, first-age goldfish weighing 8-9 grams and 7-8 cm in length can conceive only 1,000 to 1500 eggs; while the first-year goldfish with a body length of 10 to 12 cm can conceive 5000 to 10,000 eggs; weight 60 A second-age goldfish with a weight of 13 cm and a body length of 30,000 to 40,000 eggs; a third-age goldfish with a weight of 75 grams and a body length of 14.5 cm can conceive 70 to 80,000 eggs.

 The selected goldfish are matched according to the ratio of female to male in a ratio of 1:1.5-2 and then placed in the spawning pond or basin or tank, and placed in the fish nest to be spawned at the same time. 

Generally, eggs can be laid from early morning to morning the next day. After the goldfish spawning is over, first, the female and male goldfish should be taken out and kept separately in time. It should be noted that the water temperature should be the same as the original pond water temperature, and be careful to prevent the fish from being injured.

 The second is to put the fish nest into the prepared fish pond (tank, pot) for incubation. It takes 4 to 5 days when the water temperature is 20°C. The fish nest is taken out 2 to 3 days after hatching, and the fry can be cultivated.  

Farming pond construction

Build a fish pond in a place with good ventilation, sunny weather, a sufficient water source, and convenient drainage and irrigation. The area of ​​the fish pond can be built according to the size and shape of the rural courtyard.

Before building the store, the original surface should be leveled and compacted, and built with bricks. The bottom and wall of the pool should be generally 0.6-0.7m high, and the shape should be rectangular. When building the pool, water injection and drainage ports should be constructed to facilitate injection and drainage. 

The drain at the bottom of the pool must have a certain slope to facilitate drainage. Can be used for laying the bottom of the greenhouse film, economical, practical, and durable. Establish protective measures around the fish pond to prevent children from drowning. For newly built fish ponds that need to be alkaline before use, the main method is to add straw or wheat straw for soaking after filling the water. The time is about 15 days to remove the alkaline, and then rinse with clean water several times, and then add new water. Ready to use.  

Water source selection and water cultivation

The water source of yard aquaculture water must be sufficient, and the water quality must be good, non-toxic, and free of impurities. In rural courtyards with tap water, tap water is better. Tap water is convenient to get water and contains fewer bacteria, which is most suitable for goldfish breeding. 

When constructing aquaculture ponds, it is necessary to install a filtration circulation system device, which can promote ecological balance by releasing active bacteria, filtering solid substances floating in the water, and disinfecting lamp procedures. Before putting the fish, the pond must be cleaned with quicklime or bleaching powder to kill harmful organisms in the pond. After disinfection, fill it with tap water or groundwater and use it after exposure to the sun.  

Maintain the watercolor during the breeding period. The weather is sunny in summer, and the water is changed every afternoon at four o'clock in the afternoon. Each change of water is about one-third of the total water volume.

 At night, the oxygen is increased by an air pump or spraying water. If there is a serious floating head phenomenon at times, you can add hydrogen peroxide to the pool for rescue. When the temperature exceeds 32℃ in summer, a sunshade net is installed on the pool to assist in cooling down.  

Adult fish stocking

Before stocking adult fish, the floating objects and other harmful substances in the pond should be removed. The stocking density of goldfish is 100-400 fish per square meter of 1-3cm and 50-100 fish for 6-10cm. In the fry stage, monoculture is the mainstay. During the growth process, the stocking density of goldfish should be continuously adjusted according to the growth of the fish.  

Bait delivery

The feeding of bait adheres to the three principles, qualitative: high protein content, fresh and clean; quantitative: pay attention to the time when the goldfish in the pool is eaten each time, generally, it is appropriate to eat within 20-30 minutes; timing: around 7 o'clock in the morning in summer, around three o'clock in the afternoon, because the fish swim less in winter, you can feed them once around noon.  

It should be noted that every feeding time must be fed once, and the duckweed or a small amount of pellet feed needs to be properly fed according to the appetite of the fish. In courtyard farming, artificial synthetic pellet feed is mainly used. Feed is a very good auxiliary bait, and it is also the best substitute when natural bait is in short supply.  

Disease prevention

In courtyard farming, we must insist on prevention, timely diagnosis, and symptomatic medication. Especially from winter to spring, due to the lack of movement in winter for a long time and insufficient sunlight, goldfish have weaker physique.

This time is the easiest to incubate period. At the beginning of each spring season, keep in the sun frequently to enhance the physique of the goldfish. Disinfection of ornamental fish ponds and breeding tools. Combining with the water change in the clean pool, sprinkle strong chlorine solution on the wall and bottom of the pool, or use a small water body medicinal bath such as 3% NaCl solution or 20mg/L KMnO ₄ solution.

Disinfect for 20-30 minutes and rinse with clean water for use. Boxes, dip nets, and other tools are regularly disinfected with disinfectant. In the epidemic season of fish diseases, on the basis of spraying medicine to disinfect the whole pond, the medicine bait is fed regularly. And pay special attention to prevent cats, rats, frogs, and related water birds from harm.

Goldfish Monograph

The biggest feature is the detailed record of a variety of rare species. There are more than 50 varieties mainly introduced, and for each introduced one, one of three similar varieties must be mentioned. Generally speaking, the colors of goldfish are mostly red and black, and most of the species recorded in "Zhuyupu" are red spots with white background, which should be the precious species advocated by the author's era. The book has very detailed criteria for judging the merits of goldfish species, including "back theory", "lip theory", "head theory", "gill theory", "supply theory", "eye theory", and "scale tube theory". ", "tail theory", "front fin theory", "middle fin theory", "back fin theory", "back fin theory", "body fin theory", "belly theory". Setting standards in this way is the most detailed of all goldfish books in ancient China.