Effects of monochromatic light on proliferation response of splencyte in broilers.
To investigate the effects of various monochromatic lights on splenocyte proliferation responses, a total of 260 Arbor Acre male broilers on P1 (post-hatching day 1) were exposed to blue light (BL), green light (GL), red light (RL) and white light treatments by light emitting diode system for 7 weeks, respectively. All light sources were equalized on the intensity of 15 lx and light period of 23 h daily. Morphological change of spleen and response of splenocyte proliferation were assessed by using histochemistry staining and colorimetric test in cultures of purified splenic cells. The results were as follows: (1) At P21, GL increased significantly the spleen weight by 163.6% and spleen index by 118.8% compared with RL (P < 0.05). Until P49, BL enhanced significantly the spleen weights by 42.2% compared with RL (P < 0.05), but no significant difference was found in the spleen index among four light-treated groups (P > 0.05). (2) Compared with RL, GL increased significantly the diameter of splenic nodule and area of periarterial lymphatic sheath at P21 by 87.2 and 58.1%, respectively (P < 0.05); BL increased significantly the diameter of splenic nodule and area of periarterial lymphatic sheath at P49 by 64.4 and 50.5%, respectively (P < 0.05). (3) At P21, GL enhanced spleen lymphocytes proliferation in response to concanavalin A compared with RL by 50.0% (P < 0.05). Until P49, the mitogenic response in BL was significantly higher (29.4%) than that of RL (P < 0.05). (4) The interleukin-2 (IL-2) bioactivity was significantly increased to 34.3% in GL than in RL at P21 (P < 0.05). Until P49, the IL-2 bioactivity in BL was significantly higher (62.2%) than that of RL (P < 0.05). (5) There was no significant difference in the nitric oxide (NO) concentration of splenocyte among RL, GL and BL groups at P21 (P > 0.05), but the concentration in RL group at P49 was significantly increased, 59.0 and 63.7% compared to that of GL and BL groups, respectively (P < 0.05). These results suggested that the monochromatic light affected splenocyte proliferation mainly because of alterations in IL-2 bioactivity and NO production in splenocyte of broiler. In early stage of broiler growth, the action of GL was obvious, while the response of BL was stronger in later stage.
Xie
D
D
Laboratory of Anatomy of Domestic Animal, College of Animal Medicine, China Agricultural University, Haidian, Beijing 100094, China.
Wang
Z
Z
Cao
J
J
Dong
Y
Y
Chen
Y
Y
D000818:Animals; D002455:Cell Division / Q000528:radiation effects*; D049109:Cell Proliferation / Q000528:radiation effects*; D002478:Cells, Cultured; D002645:Chickens; D007150:Immunohistochemistry / Q000662:veterinary; D008027:Light; D008297:Male; D011897:Random Allocation; D013154:Spleen / Q000166:cytology*