Melatonin’in Kanatlı Hayvanlarda Önemi

Abstract

Intensive production practices, faulty maintenance and feeding, unsuitable keeping conditions, antinutritional factors in feeds and similar abnormalities lead to irregularities in both hormone and enzyme systems in poultry. Especially, due to disorders in endocrine system, a specific hormone, melatonin, can not be produced or underproduced, and thus its metabolic and physiological functions are negatively affected in the organisms. Melatonin (ML) is one of the important hormones that prevent metabolic and physiological disorders in poultry but does not attract attention by poultry scientist. ML regulates the brain's biological clock, acts on respiration, circulation, excretion, reproduction and immunity system. ML helps regulate feed consumption, energy metabolism and body heat. It also provides elimination of free radicals in the body. ML stimulates growth hormone secretion and, thus, effects growth performance of poultry positively. It is considered necesary to focus more effectively on the melatonin hormone, which is a positive contribution to animal welfare by correcting metabolic-physiological disorders in poultry. In this review, the definition of melatonin, its interaction with other hormones, its effect on the physiological and metabolic functions of poultry were examined.

Influence of Different Light Spectra on Melatonin Synthesis by the Pineal Gland and Influence on the Immune System in Chickens

“…Melatonin secretion from the pineal gland in the dark is a reflection of the circadian rhythm [ 65 , 66 , 67 ]. The pineal gland has a complementary role in regulating the rhythmic function of the endocrine system [ 68 ], which controls circadian patterns of melatonin biosynthesis and photoreceptors [ 69 , 70 ].…”

“…The most important function of the pineal gland is to produce and release melatonin into circulation. Its production in birds is controlled by three main mechanisms: direct light reception, endogenous reception, and noradrenergic transmission [ 69 , 81 ].…”

“…Melatonin is one of the important hormones that prevent metabolic and physiological disorders in birds. Melatonin regulates the biological activity of the circadian system, acts on respiration, circulation, excretion, reproduction, and the immune system, and also ensures free radical scavenger activity [ 69 ].…”

Impact of Housing Environment on the Immune System in Chickens: A Review

“…Which underlying mechanisms may be responsible for this effect? Melatonin sets the internal biological clock governing different diurnal and seasonal cycles or rhythms in various physiological systems in birds [158]. Melatonin production is stimulated during the scotophase and inhibited by light during the photophase [158].…”

“…Melatonin sets the internal biological clock governing different diurnal and seasonal cycles or rhythms in various physiological systems in birds [158]. Melatonin production is stimulated during the scotophase and inhibited by light during the photophase [158]. Exogenous administration of melatonin was shown to increase lymphocyte proliferation [117,121,125,142,143,159] and leukocyte numbers [121,159] and to decrease production of pro-inflammatory cytokines in chickens [121,125].…”