title: Effects of monochromatic light sources on sex hormone levels in serum and on semen quality of ganders.
abstract: Light is an essential external factor influencing various physiological processes, including reproductive performance, in birds. Although several attempts have been made to understand the effect of light on poultry production, the effect of light of a particular wavelength (color) on the reproductive function in geese remains unclear. This study evaluated the effect of various monochromatic light sources on the levels of sex hormone and on semen quality of ganders. Of 30 male White Roman geese in their third reproductive season (average age=3 years), 27 were divided into three groups receiving monochromatic white or red or blue lights. The birds were kept in an environmentally controlled house with a lighting photoperiod of 7L:17D for six weeks as the adaptation period. The photoperiod was subsequently changed to 9L:15D and maintained for 24 weeks. Three ganders at the beginning of the study and three from each group at the end of the adjusting period and the 20th and 30th week of the study period were sacrificed, and their testes and blood samples were collected for determining the sex hormone levels. Semen samples were collected for determining semen quality parameters, including the semen collection index, sperm concentration, semen volume, sperm motility, sperm viability, sperm morphology, and semen quality factor. The results showed that the testosterone and estradiol levels remained unchanged in all three groups at all time points. The ratio of testosterone to estradiol of ganders exposed to white light was significantly higher than that of ganders exposed to red light at the 30th week (P<0.05). Semen collection index and sperm viability of ganders exposed to blue light were significantly the lowest (P<0.05). Moreover, sperm motility, sperm viability, and percentage of morphologically normal spermatozoa of ganders in white light were the highest (P<0.05). In conclusion, the results of this study suggested that artificial illumination with white light may maintain a better semen quality than that with red or blue lights in ganders.
authors.affiliation: Department of Animal Science, National Chung Hsing University, Taiwan; Changhua Animal Propagation Station, Livestock Research Institute, Council of Agriculture, Taiwan.
authors.forename: Shen-Chang
authors.initials: SC
authors.lastname: Chang
authors.affiliation: Department of Animal Science, National Chung Hsing University, Taiwan.
authors.forename: Zi-Xuan
authors.initials: ZX
authors.lastname: Zhuang
authors.affiliation: Department of Animal Science, National Chung Hsing University, Taiwan; Changhua Animal Propagation Station, Livestock Research Institute, Council of Agriculture, Taiwan.
authors.forename: Min-Jung
authors.initials: MJ
authors.lastname: Lin
authors.affiliation: Department of Animal Science, National Chung Hsing University, Taiwan.
authors.forename: Chuen-Yu
authors.initials: CY
authors.lastname: Cheng
authors.affiliation: Changhua Animal Propagation Station, Livestock Research Institute, Council of Agriculture, Taiwan.
authors.forename: Tsung-Yi
authors.initials: TY
authors.lastname: Lin
authors.affiliation: Changhua Animal Propagation Station, Livestock Research Institute, Council of Agriculture, Taiwan.
authors.forename: Yu-Shine
authors.initials: YS
authors.lastname: Jea
authors.affiliation: Department of Animal Science, National Chung Hsing University, Taiwan; Agricultural Biotechnology Center, National Chung Hsing University, Taichung 40227, Taiwan; Center for the Integrative and Evolutionary Galliformes Genomics, iEGG Center, National Chung Hsing University, Taichung 40227, Taiwan; Center of Nanoscience and Nanotechnology, National Chung Hsing University, Taichung 40227, Taiwan. Electronic address: syhuang@dragon.nchu.edu.tw.
authors.forename: San-Yuan
authors.initials: SY
authors.lastname: Huang
mesh_terms: D000818:Animals; D046090:Anseriformes / Q000502:physiology*; D001835:Body Weight; D004958:Estradiol / Q000097:blood*; D006799:Housing, Animal; D008027:Light; D008297:Male; D009929:Organ Size / Q000528:radiation effects; D012661:Semen / Q000502:physiology*; D055101:Semen Analysis / Q000662:veterinary*; D013737:Testis / Q000033:anatomy & histology / Q000528:radiation effects; D013739:Testosterone / Q000097:blood*
chemical_list: D013739:Testosterone; D004958:Estradiol
keywords: Ganders; Monochromatic light; Semen quality traits