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The most common is sleep, in which 58% of the water floats like a log
As a result of observations on farms and laboratories, there is no sleeping on the ground.
One study found that in addition to taking some time to come to the surface to breathe in the gut, lozenges come close to the surface and fall asleep. Getty Images Bank
Loch, buried in the pearls of paddy fields, swamps and shallow streams, seems to be sleeping downstairs, but unexpectedly, research shows they are floating in the water. The loaves were found lying or lying asleep, in various positions, mainly in the water at night. Zhang Ning, a biologist at China’s Sichuan Agricultural University, and other Chinese researchers observed the bread on farms and labs in China and said that “this fish has a completely new behavior not found in other fish.” It’s a special kind of bread, ”he said in a paper published in the latest issue of the scientific journal Applied Animal Behavior. The researchers looked at four loch farms and laboratories in Sichuan Province and found that the sleeping behaviors of bread were divided into five categories. It did not have the shape to sit comfortably on the ground like other fish, they all slept floating in the water.
Five sleeping positions of bread. Floating horizontally from above, lying in a horizontal position, lying on the side in a horizontal position, standing on the handle, etc. Presented by ‘Ning Zhang et al. (2021)’ Applied Animal Behavior ‘.
Floating like a tree trunk was the most common, at 58%, followed by standing in the middle of the water with the head facing 24% above. The lateral position is also 13%. However, the downward facing posture was 3% and the horizontal upward position on the abdomen was 2%. This behavior occurred in more than 1–3% of individuals at bread and 5% in labs, and was more common at night than during the day. Most of the time floating in the water was less than 30 seconds, but individuals that lasted 10 minutes or several hours were also observed. The reason why researchers consider this behavior to be sleepy is that Loch in this condition is said to be in a state of numbness, meaning that when people approach or touch it it does not react immediately, reducing the way it breathes through its gills. Less than half of the normal rate. Current studies have shown that fish sleep similar to terrestrial vertebrates through brain wave changes, decreased heart rate, muscle relaxation, and emotional dullness.
A view of Loch Farm. The dormant appearance of bread is difficult to observe in the wild because it is found only in 1 ~ 3% of farms. Reporter Park Mi-hyang
Analysts say, “At first, the fishermen thought that the turkey was unwell, but it was later confirmed that there was no ill health.” The survival rate of breads bred for 130 days from birth in the laboratory reached 85% and their bodies doubled. Then, why do breads float and sleep? “Floating below is a highly dangerous behavior for predators,” the researchers said.
Although the Chinese loch (scientific name Paramisgurnus dabryanus) is not native to Korea, it is likely to have already been introduced. Hosted by TCM Wiki.
In addition to gill breath, lozenges breathe through the skin and intestines. The researchers said in a study that “loch requires intestinal respiration with its gills, even when oxygen is sufficient.” Different sleep levels were thought to depend on the amount and location of air in the intestine. Floating poses require less energy to maintain body balance than the floor and are easier to relax muscles. “The evidence is that chicks begin to fall asleep after two weeks of intestinal respiration,” the researchers said. “Apart from this bread, we found similar behavior in another species of loch, Loch,” the researchers said. Loch is a fish native to Korea.
Loch was released to repel mosquitoes. Bread in Korea is also more likely to have sleeping behavior. By Kim Myung-jin, staff correspondent [email protected]
Meanwhile, although Loch, the target of this study, is not native to Korea, it is known that it was recently imported from China and widely cultivated. In 2019, the Ministry of Environment designated this bread as a ‘migratory creature’. It spreads as an exotic species in the United States, Japan and Europe. However, Lee Wan-oak, a research professor (fisherman) at Chunsunhyang University, said: “It’s hard to say that bread can not be found in domestic rivers because direct loach and fry are heavily imported from China.” He added, “There may be sleep behaviors in Korea like loch and fish, but it is difficult to observe them in their natural state except for abduction.” In fact, Yang-yol Ryu, who has been cultivating bread in Yongbyong, Kyongyi-do for 13 years, said, “During the day, except for the occasional gut-breathing surface, they are on the ground, but there are people on the surface around 9-10 at night.” Application Animal Behavior Science, DOI: 10.1016 / j.applanim.2021.105510 Reporter Joe Hong-siop [email protected]