摘要
光周期可以影响动物体内褪黑素(MLT)的分泌,而MLT能参与机体多种生理功能的调节。本试验旨在研究光周期对山羊MLT分泌、免疫和抗氧化功能及相关基因表达的影响。将18只6月龄雌性绒山羊随机分为3组:对照(CG,自然光周期)组、短光照(SDPP,光照8 h/d,黑暗16 h/d)组和渐减光照(SIPP,光照时间从16 h/d逐渐缩短到8 h/d)组。试验期为60 d。结果表明:与对照组相比,1)在试验第30天,SDPP显著增加了血清MLT含量(P<0.05),在试验第60天,SIPP显著增加了血清MLT含量(P<0.05);2)在试验第30天,SDPP组血清总超氧化物歧化酶(T⁃SOD)、谷胱甘肽过氧化物酶(GPx)和过氧化氢酶(CAT)活性显著升高(P<0.05),丙二醛(MDA)含量显著降低(P<0.05),而SIPP组上述指标均无显著变化(P>0.05);在试验第60天,SDPP组和SIPP组血清T⁃SOD、GPx和CAT活性均显著升高(P<0.05),MDA含量显著降低(P<0.05);3)在试验第30天,SDPP显著提高了血清免疫球蛋白G(IgG)、白细胞介素-1β(IL⁃1β)和白细胞介素-2(IL⁃2)含量(P<0.05);在试验第60天,SDPP和SIPP均显著提高了血清IgG含量(P<0.05),此外,SDPP显著提高了血清IL⁃1β、IL⁃2和肿瘤坏死因子-α(TNF⁃α)含量(P<0.05),而SIPP仅显著提高了血清IL⁃1β含量(P<0.05);4)在基因表达方面,在试验第30天,SDPP显著上调了白细胞中SOD1、GPx1、GPx4、CAT、核转录因子2(Nrf2)、IL⁃1β、和IL⁃2基因相对表达量(P<0.05);在试验第60天,SDPP组白细胞中SOD1、CAT、GPx4、IL⁃1β和IL⁃2基因相对表达量显著提高(P<0.05),SIPP组白细胞中SOD1、GPx1、CAT、IL⁃1β和IL⁃2基因相对表达量显著提高(P<0.05)。上述结果表明,持续短光照能分泌更多的MLT,提高山羊的免疫和抗氧化功能。
Photoperiod can affect the secretion of melatonin(MLT),which can participate in a variety of physiological regulation.The purpose of this experiment was to study the effects of photoperiod on MLT secre⁃tion,immune and antioxidant function and related gene expression of goats.Eighteen 6⁃month⁃old female cash⁃mere goats were randomly divided into 3 groups:control(CG,natural light)group;short⁃day photoperiod(SDPP,8 h light,16 h dark)group and shortening⁃day photoperiod(SIPP,lighting time is gradually short⁃ened from 16 to 8 h/day)group.The experimental period was 60 days.The results showed as follows:com⁃pared with control group,1)SDPP significantly increased the content of MLT in goat serum(P<0.05)at day 30 of experiment,while SIPP significantly increased the content of MLT at day 60 of experiment(P<0.05).2)The activities of total superoxide dismutase(T⁃SOD),glutathione peroxidase(GPx)and catalase(CAT)in SDPP group significantly increased(P<0.05)and the content of malondialdehyde(MDA)significantly de⁃creased(P<0.05)at day 30 of experiment.No effect of SIPP was observed(P>0.05).At the day 60 of ex⁃periment,the activities of serum T⁃SOD,GPx and CAT in SDPP group and SIPP group significantly increased(P<0.05),and the content of MDA significantly decreased(P<0.05).3)At day 30 of experiment,the con⁃tents of immunoglobulin G(IgG),interleukin⁃1β(IL⁃1β)and interleukin⁃2(IL⁃2)in serum significantly in⁃creased in SDPP group(P<0.05).At the day 60 of experiment,SDPP and SIPP both significantly increased the content of IgG in serum(P<0.05).For cytokines,SDPP significantly increased the contents of IL⁃1β,IL⁃2 and tumor necrosis factor⁃α(TNF⁃α)in serum(P<0.05),while SIPP only significantly increased the content of IL⁃1βin serum(P<0.05).4)In terms of gene expression,SDPP significantly upregulated the gene relative expression levels of SOD1,GPx1,GPx4,CAT,nuclear transcription factor 2(Nrf2),IL⁃1β,and IL⁃2 in leukocytes at day 30 of experiment(P<0.05).At day 60 of experiment,SDPP goat had higher gene relative expression levels of SOD1,CAT,GPx4,IL⁃1βand IL⁃2 in leukocytes(P<0.05).The gene relative expression levles of SOD1,GPx1,CAT,IL⁃1βand IL⁃2 in leukocytes significantly increased in SIPP(P<0.05).These results show that continuous short illumination can secrete more MLT,and improve goat’s im⁃mune and antioxidant function.
作者
毛晨羽
邢媛媛
石璐璐
徐元庆
金晓
史彬林
MAO Chenyu;XING Yuanyuan;SHI Lulu;XU Yuanqing;JIN Xiao;SHI Binlin(College of Animal Science,Inner Mongolia Agricultural University,Hohhot 010018,China)
出处
《动物营养学报》
CAS
CSCD
北大核心
2020年第2期736-745,共10页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家重点研发计划项目（2016YFD0500508)
