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How to Cleverly Identify Whether Fish Have Eaten Their Fill
1. Pay close attention to how long the fish take to eat at the feeding tray or feeding ground. If, after a certain amount of feed is put in (the normal feeding amount), the fish finish the feed in less than 2 hours, it means the feed is insufficient and some fish have not eaten or have not eaten their fill, so an appropriate amount should be added. If the feeding amount per ten-day period is fixed and the daily feeding amount within the period is the same, but by the end of the period the feed put in is finished by the fish in less than 2 hours, it means the fish have gained weight and the feed amount should be increased. When feeding compound pellet feed, if the feed has already been finished but the school of fish is still swimming rapidly on the surface layer searching for food and is unwilling to sink into the "second layer of water," it indicates the fish have not eaten their fill. If the school of fish has already dispersed from the feeding tray or feeding ground and there is still leftover bait, the fish have eaten more than their fill, and the feeding amount can be appropriately reduced next time.
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How to identify and control jujube witches' broom? The methods explained clearly in one article
Jujube witches' broom, commonly known as "male jujube tree", is a devastating disease of jujube trees. In severe cases, it can cause mass death of jujube trees and even destroy the entire orchard. 1. Symptom identification (1) The initial symptoms appear after flowering, manifested as degeneration of floral organs and abnormal sprouting of buds; the leaves that grow out are narrow and small, forming clustered branches and leaves, and the young leaves show vein clearing, yellowing and curling into a spoon shape. (2) The leaves of diseased trees show obvious pathological changes after flowering: first the mesophyll turns yellow, then gradually the entire leaf yellows, the edges curl upward, and later the leaves become hard and brittle, dull and lusterless. (3) On the current-year vegetative shoots of diseased plants, the normal buds and
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How to identify high-quality fish fry? Selection tips every farmer must know
"Good seed is half the profit, good seedlings are half the grain." Robust, high-quality fish fry are not only an important factor in improving the survival rate of fry, but also an important foundation and guarantee for increasing fish yield and boosting economic returns. High-quality fish fry should have: appropriate and uniform size, robustness without injury, lively movement, and strong feeding competitiveness. Specifically, identifying high-quality fish fry can be summarized as "three looks and one sampling." First look: the size of the fry. The harvested size of the same fish species from the same pond should be neat and uniform, with little difference in body length and weight. In contrast, inferior fry with large individual differences and unevenness, due to reasons such as food competition, mixed germplasm, and poor feeding, often have a very low overall survival rate. Second look: the body color of the fry. High-quality fry have bright and glossy body color. Different species and different feeding methods produce fry with different body colors. Generally speaking, high-quality silver carp fry should have a silver-gray back and silvery-white sides and belly; high-quality grass carp fry have a light golden-yellow body color, with gray-black net-like scales relatively obvious, and the more robust the fish, the more prominent the light golden-yellow; high-quality bighead carp fry mostly have a light golden-yellow body color, with black markings all over the body not very obvious. If the body color of the fry is darker, or even blackish, it indicates that the fry are weak or diseased. The gloss on the body surface of the fry is caused by the mucus layer covering the body surface, which is rich in proteases, lysozymes, etc., and has the function of protecting the scales and skin of the fry from invasion by diseases and pests; fish or weak fry lack a mucus layer, so the body surface has no gloss. Of course, when fry are attacked by external diseases and pests, they will also secrete a large amount of mucus and lose their gloss. For example, when fish are attacked by Ichthyophthirius multifiliis, the body surface will be covered with a thick layer of mucus, which is a stress response made by the fry to external invasion. Third look: the activity of the fry. High-quality fry are lively in movement, strongly gregarious, quickly gather in groups and dive to the bottom when startled, have strong feeding competitiveness and strong upstream swimming ability. When crowded, the fry heads point downward, and only the tails can be seen constantly fanning; while weak or diseased fry with poor constitution move slowly, do not form groups, swim alone, have weak feeding competitiveness, and poor upstream swimming ability. One sampling: randomly sample fry to check their quality. High-quality fry jump violently when out of water, are plump, with small heads and thick backs, glossy body color, moist muscles, intact scales and fin rays, gill covers not open, tails not bent, no parasites or wounds on the body surface, and normal body shape without deformities. In contrast, weak or diseased fry jump weakly, have incomplete scales and fin rays, congestion, emaciated bodies, large heads and small tails, backs as thin as a knife edge, and even those with "no belly" or that "stick to the net" are considered inferior fry.
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How to identify a sick rabbit? Three methods to help you tell
First, look: A sick rabbit is listless, emaciated, with bones showing, a ruffled and lusterless coat, and does not shed fur according to the molting season. A healthy domestic rabbit has a strong appetite and eats quickly; a sick rabbit has a poor appetite, eats slowly or refuses food. The droppings of a healthy domestic rabbit are pellet-shaped, oval, uniform in size, with a round, smooth surface. If dry, hard, small droppings appear, it indicates constipation, and more green, succulent feed should be given; if the droppings are tadpole-shaped or soft and loose, this indicates indigestion, and charcoal powder, yeast tablets, etc. should be added to the feed; if the droppings are piled up and
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Detailed Guide to Identifying and Controlling the Main Diseases of Lilies
Lilies belong to the genus Lilium in the family Liliaceae and are perennial herbaceous plants, also known as wild lilies and medicinal lilies. In recent years, lily cultivation has been seriously threatened by diseases, mainly lily leaf blight, phytophthora blight, bulb basal rot, and viral diseases. These diseases often occur together, worsening the damage. The usual incidence rate is 10%-15%, and in severe cases it can reach 20%-30%. 1. Several main diseases of lilies (1) Lily leaf blight, also known as lily gray mold, is a commonly occurring disease. It mainly damages leaves, but can also infect stems,
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Detailed Guide to Identifying Eel Fry Species, Teaching You How to Tell Them Apart
Currently, it is the eel fry flood season on the Yangtze River, and fishing boats from Jiangsu, Zhejiang, Anhui, Fujian, Shandong and other provinces and cities gather at the Yangtze River estuary to fish. Because the eel fry produced in the Yangtze River are "Japanese eel," they are superior to the "European eel" produced in France, the "American eel" produced in the United States, the "Australian eel" produced in Indonesia and Australia, and the "Philippine eel" produced in the Philippines. Not only are there obvious price differences, but they are also suitable for aquaculture in our country. To prevent farmers from being deceived when purchasing eel fry, the characteristics and identification methods of various eel fry are introduced as follows: 1. Look at body shape and body color. Japanese eel fry are
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Detailed Guide to Identifying and Controlling the Green Peach Aphid
The green peach aphid (Myzus persicae) causes extremely widespread damage. Adults and nymphs gather in groups on the undersides of leaves and on tender shoots to suck sap. Infested leaves curl irregularly toward the underside, which affects the growth of new shoots on peach trees and spreads viruses. The green peach aphid can damage more than 300 species of plants, making it one of the most difficult pests to control. Winged viviparous females are green or yellow-green; brown and reddish-brown forms also occur, with colors varying according to the host; wingless viviparous females are green, yellow-green, apricot-yellow, and reddish-brown; nymphs are small and pale red; eggs are mostly laid on the host's shoot tips, bud axils, and small branch forks
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How to identify the early symptoms of sick rabbits, teaching you to spot them early
Rex rabbits have delicate bodies and are sensitive to external conditions, with the characteristics of sudden onset, rapid death, and rapid recovery with timely treatment. Since rabbits often fall ill at night, feeding them in the morning is the time to observe cage by cage and litter by litter, making it easiest to identify suspicious sick rabbits. Specifically, you can start with checking, looking, touching, and measuring. 1. Check. A healthy rabbit has pink ears and bright eyes. If the ears are red or light purple, it indicates overheating, which can be relieved by placing the rabbit in a ventilated cage with less movement; if the ears are pale and cool to the touch, it indicates drinking too much cold water or being chilled, and
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How are bee diseases diagnosed? Observe the bee's body to identify the disease
State. Sick bees often appear dull, slow to respond, listless, unable to take flight, restless, resting on one side, or slowly rolling and crawling inside and outside the hive. Head. A healthy bee's head moves freely; when it shakes its head and scratches, it may have parasites such as bee mites. Wings. A healthy bee has 4 intact wings that open and close freely and allow free flight. A sick bee's wings are incomplete, or it quivers its wings and loses the ability to fly. Some young bees have curled wings, mostly due to curled-wing disease, and incomplete wings are mostly caused by bee mite damage.
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Detailed Guide to Identifying and Controlling the Main Diseases and Pests of Oyster Mushrooms
The most serious damage is contamination by foreign molds. Common contaminating molds include Trichoderma, green mold, yellow mold, Rhizopus, and others. The main control methods are: choose materials free of mold, compost and ferment the substrate and sterilize it, strictly disinfect the cultivation site, and promptly remove any contaminated material. Provide proper ventilation to prevent excessively high temperatures and humidity. Oyster mushroom cultivation also frequently shows physiological disorders: ① Partial death of small mushrooms: when there are too many small mushrooms, some will die, mainly from "starvation" due to insufficient nutrients; spraying water too early or excessively high humidity can also cause small mushrooms to die.
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