body length Learn more about body length
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How to identify the quality of fish species in aquaculture
Strong fish species is not only an important basis for increasing adult fish production, but also one of the main conditions to improve the survival rate of fish species. The main standards for identifying the quality of fish species are 5.
2019-02-26 -
The elegant Little Princess "Fairy Fish" Culture Collection of Tropical Fish
Fairy fish, also known as swallow fish, angel, small fairy fish, small fin sailing fish, etc., Riceae fish, native to South America Guiana, Brazil. The fairy fish grows 12-15 centimeters.
2019-02-28 -
How to choose to kiss eel
If we want to choose the seedlings with more eggs, high fertilization rate, emergence rate and good quality, we must choose the rice field eel with a certain age, weight, strong physique, no serious disease and trauma as the parent eel. In the non-breeding season, it is difficult to distinguish between female and male eel in appearance, and usually stay on the basis of body length. Most of the ricefield eels are female when their body length is 20 cm-35 cm, and most of them are male when their body length is more than 45 cm. Under normal circumstances, you can choose to stay at 3:1 according to the above two body length groups.
2019-01-16 -
Brief introduction of raccoon dog varieties and its selection criteria
1. Racoon dogs belong to carnivores, canines and medium-sized fur animals. According to Chinese fauna (1987), racoon dogs can be divided into three subspecies, namely named subspecies, northeast subspecies and southwest subspecies: ① named subspecies: from Jiangsu, Zhejiang, Anhui, Jiangxi, Hunan, Hubei, Fujian, Guangdong, Guangxi and other provinces and regions, with 50~53cm body length, short coat, brownish yellow undercoat and few black hair tips. The black vertical lines on the back are also not obvious. ② northeast subspecies: of Heilongjiang, Jilin, Liaoning and other provinces, body length 5
2019-01-15 -
Brief introduction of raccoon dog varieties and selection criteria
Racoon dogs belong to carnivores, canines and medium fur animals. According to Chinese fauna (1987), racoon dogs in China can be divided into three subspecies, namely named subspecies, northeast subspecies and southwest subspecies: ① named subspecies: from Jiangsu, Zhejiang, Anhui, Jiangxi, Hunan, Hubei, Fujian, Guangdong, Guangxi and other provinces and regions, 50~53cm in length, short coat, brown undercoat, less black hair tips, and no obvious black vertical lines on the back. ② northeast subspecies: from Heilongjiang, Jilin, Liaoning and other provinces, with a body length of 56cm 90c
2019-01-11 -
Aphid disease of oleander
Morphological characteristics: aphids belong to Homoptera, Aphididae, wingless parthenogenetic aphids: body length 2.3mm, wide 1.2mm, oval, yellow body, obvious markings in the eighth ventral segment. There are obvious reticulation on the body surface. The middle frontal tumor is raised. The top is flat; the antennae are tiled, with a body length of 2 to 3. The ventral tube is long tube-shaped, the tail is tongue-shaped, hanging in the middle, and there are 11-14 long curly hairs on it. Winged parthenogenetic aphids: body length 2.1mm, wide 1.Omm, long ovate; head and chest black; antennae are body length 3 big 4. There are small marginal tumors in segments 2-4 of the abdomen, and the abdominal tube is a long cylinder.
2019-01-15 -
How do peacock fish divide male and female
How do peacock fish divide male and female
2018-09-08 -
Parent cultivation technique of small yellow croaker Pseudosciaena Crocea
Small yellow croaker (PseudosciaenapolyactisBleeker) belongs to Perciformes, Perciformes, Coleopteridae and Pseudosciaena Crocea, distributed in the Bohai Sea, the Yellow Sea and the northern part of the East China Sea. It is a warm near-bottom fish and was originally one of the four major marine economic fishes in China. The resources of Pseudosciaena Crocea have declined seriously since the 1950s. In this paper, the author introduces the technique of parent culture of Pseudosciaena Crocea. Through the observation of the growth process of Pseudosciaena Crocea, the growth parameters are recorded, which are the artificial reproduction and human of Pseudosciaena Crocea.
2019-01-16 -
Brief introduction of raccoon dog varieties and selection criteria
1. Racoon dogs belong to carnivores, canines and medium-sized fur animals. According to Chinese fauna (1987), racoon dogs can be divided into three subspecies, namely named subspecies, northeast subspecies and southwest subspecies: ① named subspecies: from Jiangsu, Zhejiang, Anhui, Jiangxi, Hunan, Hubei, Fujian, Guangdong, Guangxi and other provinces and regions, with 50~53cm body length, short coat, brownish yellow undercoat and few black hair tips. The black vertical lines on the back are also not obvious. Northeast subspecies of ②: from Heilongjiang
2019-01-16 -
What are the species of grouper?
What are the species of grouper?
2018-09-08 -
A collection of pictures of fox breeds
A collection of pictures of fox breeds
2018-07-07 -
Eel seedlings are bred by themselves.
1. The selection and cultivation of parent eel as breeding eel requires strong physique and lively swimming. The body color should be thick black mud, yellowish brown or black flowers, green brown. According to the source of parent eel, the wound caught in cage on the same day was smaller. Monopterus Albus has the characteristics of sexual transformation. Monopterus Albus is basically female at the age of 1 and 2, the proportion of males increases gradually after spawning at the age of 2, and is basically male at the age of 6. In the non-spawning season, it is difficult to distinguish between male and female, generally based on body length and weight, with a body length of 37cm to 50cm and a body weight of 7.
2019-01-16 -
large yellow croaker
(1) Morphological characteristics: large yellow croaker body elongated, flat side, dorsal and ventral margin wide arc, slender tail stalk. The body length is 3.5 - 4.2 times the body height and 3.4 - 3.8 times the head length. The head length is 3.9 - 5.0 times the length of the snout and 3.5 - 5.7 times the eye diameter. The length of the tail stalk is 3.4 - 3.8 times the height of the tail stalk. The dorsal and upper sides are yellow-brown, the lower and ventral sides are golden yellow, the dorsal and caudal fins are grayish yellow, the pectoral and ventral fins are yellow, and the lips are orange. The head side is flat, large and pointed obtuse, with developed mucus cavity. Mouth obtuse, larger than eye diameter. Kissing pleats intact, not
2019-01-16 -
What is the classification standard of edible fungi?
What is the classification standard of edible fungi?
2020-12-09 -
Culture Technology of Erythroculter ilishaeformis
Culture Technology of Erythroculter ilishaeformis
2018-09-08 -
What are the species of tree frogs? Is it poisonous?
Tree frog has a slender and flat body, long hind legs, large sucker, well-developed web between fingers and toes, and can be used to glide in the air. the main skeletal features are the same as frogs. It is arboreal, and its appearance and living habits are similar to those of the genus Rana, but its genetic relationship is very far away. that
2020-11-11 Tree frogs species which are poisonous tree frogs many bodies -
Identification skills of excellent racing pigeons
Select good racing pigeons, just like picking athletes. There are two major categories of carrier pigeon competitions in the world: one is the "evaluation race", and the other is the speed race, which is divided into short-and medium-distance, long-distance and ultra-long-distance races. A good carrier pigeon must be of the right size. Balance and coordination are the most important conditions for a good racing pigeon to show by its appearance, while length and weight are closely related to whole body balance and coordination. In the team of champion pigeons, there may be racing pigeons that are too big or too small, but most champion pigeons are of medium size.
2019-01-16 -
What kind of food do thirteen-star ladybugs eat?
What kind of food do thirteen-star ladybugs eat?
2018-07-04 -
What kind of fish is a tiger fish?
Tiger fish belong to offshore bottom fish, and their body color varies with depth, generally dark brown in coastal shallow waters and red or yellow in deep waters of the open sea. Do you know what it looks like? What kinds do you have? What does the tiger fish look like? Old
2020-11-11 Tiger fish what is it tiger belong to offshore bottom miscellaneous fish -
The technique of culturing catfish in cage
Catfish cultured in cages, 17.5 kg per square meter, the economic benefit is 5-10 times that of grass carp and carp. The main techniques are as follows: first, set up cages and choose spacious water areas such as streams, lakes and reservoirs with fresh water quality, high dissolved oxygen and suitable pH value.
2020-11-08 Cage aquaculture catfish technology cage culture