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With the attendance of 140 professionals from the aquaculture industry, this Wednesday the sixth version of the International Photoperiod Wokshop was held, organized by Bioled. The activity took place this Wednesday, November 27 at the Cumbres de Puerto Varas hotel  

The technical part of the activity began with a presentation by Bjord Thrandur Bjornsson, director of fish endocrinology at the University of Gothenburg, who in his first intervention explained the role of light in the physiology of fish and other vertebrates. The prominent specialist told attendees how melatonin levels vary depending on the influence of light. This influences the growth and maturation of the fish, showing examples with rainbow trout. "Light is the stimulus that gives information to the animal about the circadian cycle for its daily activities," he said, revealing basic principles of photoreception, noting that it is an incredible process. In addition, it showed the difference in the colors of the lights, indicating that the pineal gland responds differently to the colors of the light. Thrandur also discussed what happens after the pineal gland produces melatonin, stressing that melatonin regulates the production of a number of regulatory hormones in the body.


"Several of the hormonal changes in fish vary according to the season of the year, given the variability of light in the environment," added Dr. Thrandur Bjornsson, explaining the hormones that most influence the different growth stages of fish (smoltification , growth, maturation).

On the other hand, the European expert pointed out that “the production of melatonin is inhibited by artificial light, depending on its intensity and color. The brain processes information from light and tells the pituitary gland whether or not to produce various hormones. " Next, he explained the relationship between photoperiod, temperature and hormonal regulation of smoltification, showing a study that sought to observe the behavior of fish with or without photoperiod.

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