What is the "sexual transformation" of female swordtail fish?
However, only the female changed from male to male, and no male to female was found.
Recently, different opinions have been expressed on this issue: swordtail fish cannot be reversed sexually, and their natural sex ratio has always been between 1:2 and 1. 5. Although the male and female reproductive organs begin to develop when the larvae of swordtail fish grow to 3 months, the sexual organs can not mature and stabilize until the age of 7-8 months. For this problem, we can continue to explore and study it in the future practice.
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Infectious pancreatic necrosis of salmon and trout
The pathogen is infectious pancreatic necrotic disease virus. Vertical transmission: eggs and semen of parent fish with virus; horizontal transmission: feces, urine and secretions of diseased fish bring the virus into the water, the route of infection is Gill and mouth. Most of the juvenile fish with symptom weight more than 5 grams are chronic, the speed of death is slow, the appearance of abdominal swelling, blackening of body color, exophthalmos, hyperemia and redness of fin base and abdomen, anus mostly dragging linear feces, slow swimming and poor feeding. Most of the fry weighing less than 5 grams are acute, the rate of death is fast, and the activity of diseased fish is slow.
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Go to Tang Ming Prawn Crackers
Materials: 3 prawns, 1 Youtiao, 4 slices of lettuce, 1 spring onion. Seasoning: a little flour, 1 tablespoon cooking wine, 5 cups of stock, 1 teaspoon salt, a little pepper. Production method: 1. Peel the prawns, remove the mud sausage, rinse the mucus with flour, rinse with water, wipe dry, then slice thin; 2. Cut Youtiao into pieces, return to the pan and fry crisp, remove and drain oil, spread in a bowl, shred lettuce, add chopped onions, and then slice.
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