石雷，李云雷，孫研研，陳繼蘭

?

光照節(jié)律調(diào)控雞繁殖性能機(jī)制研究進(jìn)展

石雷，李云雷，孫研研，陳繼蘭

（中國農(nóng)業(yè)科學(xué)院北京畜牧獸醫(yī)研究所/農(nóng)業(yè)部動物遺傳育種與繁殖（家禽）重點(diǎn)實(shí)驗(yàn)室，北京 100193）

光照是生物體重要的環(huán)境因子。現(xiàn)代家禽生產(chǎn)普遍采用人工光照。禽類視覺敏感，光照對禽類的生長發(fā)育和繁殖的影響直接關(guān)系到生產(chǎn)效率。光照是溫度、濕度和通風(fēng)因素之外的另一個(gè)重要的環(huán)境因子。此外，雞作為一種重要的模式動物，光照對其繁殖生理的影響和相關(guān)作用機(jī)制研究也具有重要科學(xué)意義。文章就禽類對光照的感知，光照節(jié)律對雞性成熟和繁殖的影響進(jìn)行歸納總結(jié)，同時(shí)概述了非自然光照節(jié)律、光照不應(yīng)性和種蛋孵化期光照技術(shù)的研究進(jìn)展，為深入理解光照節(jié)律對雞繁殖性能的影響及其調(diào)控機(jī)制提供理論參考。禽類的光感受器如眼球（視網(wǎng)膜）、丘腦深部和松果體，能夠?qū)⒐庑盘栟D(zhuǎn)變?yōu)樯镄盘枺⒁揽可窠?jīng)內(nèi)分泌系統(tǒng)，尤其是下丘腦-垂體-性腺軸，影響雞的生殖系統(tǒng)發(fā)育和繁殖行為。育成期雞群性腺發(fā)育很快，并對光照時(shí)間長短反應(yīng)敏感。光照時(shí)長過短或者過長，可能導(dǎo)致雞只生長受阻或者性成熟提前；每天維持恒定8或9 h的光照時(shí)長，可保證體況和體重在性成熟時(shí)達(dá)標(biāo)，充分發(fā)揮繁殖潛力。產(chǎn)蛋期光照節(jié)律主要包括光照刺激時(shí)間和光照時(shí)長。光照刺激能促進(jìn)雞性成熟，但必須在恰當(dāng)?shù)碾A段實(shí)施才能有效發(fā)揮其促進(jìn)適時(shí)和整齊開產(chǎn)的作用。對于黃羽種雞光照刺激時(shí)間的研究鮮有報(bào)道，生產(chǎn)中多參照蛋雞的光照方案，或適當(dāng)推延。進(jìn)入產(chǎn)蛋期的雞群，光照節(jié)律則由恒定短光照轉(zhuǎn)變?yōu)楹愣ㄩL光照，光照時(shí)長的選擇也是提高雞繁殖力的關(guān)鍵控制點(diǎn)之一。母雞產(chǎn)蛋期需要較長的光照時(shí)長以維持其高產(chǎn)，但肉種雞與蛋雞在體況、飼喂方式和生理特點(diǎn)等不同，如光照不應(yīng)性等生理特征。因此，肉種雞的光照時(shí)長短于蛋雞或蛋種雞，一般為14或15h，而蛋雞或蛋種雞為16或17h。種公雞性早熟在實(shí)際生產(chǎn)中具有重要作用，隨著精液稀釋和存儲，以及種公雞隔代利用等技術(shù)的應(yīng)用發(fā)展，種公雞光照調(diào)控技術(shù)研究也逐步開展。種公雞性成熟后采取與母雞同樣的光照時(shí)長可能會降低精液品質(zhì)，提示在公母分飼的條件下有必要對公雞和母雞進(jìn)行有區(qū)別的光照節(jié)律管理。與常規(guī)24h光照節(jié)律不同，非自然光照節(jié)律的光照制度可以提高蛋重，但可能降低產(chǎn)蛋數(shù)。非自然光照周期不符合歐盟規(guī)定動物福利標(biāo)準(zhǔn)，與飼養(yǎng)人員的正常作息時(shí)間不一致，在實(shí)際生產(chǎn)中并未廣泛應(yīng)用，但是研究非自然光照周期對了解家禽的生物節(jié)律具有一定的參考價(jià)值。

雞；光照節(jié)律；繁殖性能；調(diào)控機(jī)制

光照是生物體重要環(huán)境因子，對生命活動至關(guān)重要。光信號以周期變化、光照強(qiáng)度和光波長等屬性被動物的光感受器所感知，并轉(zhuǎn)變?yōu)樯飳W(xué)信號，調(diào)節(jié)動物生理和行為。禽類對光照敏感，在自然條件下，禽類要達(dá)到性成熟并獲得繁殖能力，須以大自然的日照長度和強(qiáng)度刺激這一客觀條件的變化為前提。因此，野生的禽類總是在大自然日照長度和強(qiáng)度逐漸延長和增加的時(shí)期進(jìn)行自然繁殖[1]。人們發(fā)現(xiàn)這種自然規(guī)律以后，就開始通過人為干預(yù)的方法控制光照，從而實(shí)現(xiàn)任何時(shí)期都可以成為雞繁殖季節(jié)的目的。在現(xiàn)代生產(chǎn)中，光照調(diào)節(jié)禽類的生長發(fā)育、生產(chǎn)和繁殖已成為一種提高生產(chǎn)效率的重要方法。光照節(jié)律是對光照和黑暗時(shí)長以及比例的控制，是光照管理中重要的調(diào)控方式。本文綜述光照節(jié)律對雞性成熟和繁殖性能的影響及相關(guān)機(jī)制研究進(jìn)展，為進(jìn)一步開展相關(guān)研究奠定基礎(chǔ)。

1 禽類對光照的感知

家禽感知來自外界環(huán)境光線的過程主要包括兩條途徑：視網(wǎng)膜感受器和視網(wǎng)膜外感受器，分別位于視網(wǎng)膜和下丘腦。家禽的繁殖活動受神經(jīng)內(nèi)分泌調(diào)控，尤其是下丘腦-垂體-性腺軸。位于禽類眼球上的視網(wǎng)膜感受器接受外界光線產(chǎn)生光信號，傳遞至下丘腦[2]，進(jìn)而作用于下丘腦-垂體-性腺軸[3]，引起家禽體內(nèi)促黃體素（luteinizing hormone，LH）和促卵泡素（follicle- stimulating hormone，F(xiàn)SH）濃度變化，影響家禽生殖系統(tǒng)發(fā)育和繁殖活動[4-8]。人類視網(wǎng)膜上存在著對藍(lán)光、綠光和紅光敏感的三種視錐細(xì)胞[9]，而禽類還具有對415 nm光線敏感的視錐細(xì)胞[3]，因此禽類與人對同一光源的感知可能不同。家禽的很多生命活動如生長和采食等，都與視網(wǎng)膜的敏感性密切相關(guān)[5]。

禽類對光的感受并不局限于視網(wǎng)膜，丘腦深層同樣存在著光信號接收器。來自外界的光可以透過顱骨，直接到達(dá)位于下丘腦上的光感受器，從而將外界光信號轉(zhuǎn)化為神經(jīng)沖動，進(jìn)而作用于下丘腦-垂體-性腺軸[3, 10-11]。刺激丘腦深層部位能夠引起生殖機(jī)能的改變[12-13]。MOBARKEY等[14]研究14L:10D對照組、紅光組和綠光組對肉種雞分子水平的影響，發(fā)現(xiàn)紅光組的促性腺激素釋放激素（gonadotropin-releasing hormone，GnRH）的mRNA表達(dá)量顯著高于對照和綠光組，紅光組和對照組LH的mRNA表達(dá)量顯著高于綠光組。利用紅光能透過顱骨刺激視網(wǎng)膜外感受器的特性。提示光照刺激雞的視網(wǎng)膜外感受器是調(diào)控繁殖性能的重要途徑之一，其作用甚至高于光線刺激視網(wǎng)膜感受器。在其他禽類中也有相關(guān)發(fā)現(xiàn)，如盲眼麻雀的睪丸發(fā)育情況與正常個(gè)體無顯著差異，即視網(wǎng)膜外受體可以介導(dǎo)性腺對光照刺激的應(yīng)答[15]。

松果體被認(rèn)為是家禽的“第三只眼”[16]，由光感細(xì)胞、神經(jīng)節(jié)細(xì)胞和支持細(xì)胞構(gòu)成。松果體細(xì)胞被認(rèn)為與視網(wǎng)膜細(xì)胞具有共同的起源[17]。松果體作為家禽的光感受器尚存在爭議。一般認(rèn)為，松果體能感受光的信號并作出反應(yīng)，由松果體分泌的褪黑激素（melatonin，MT）受光照的制約。光照明期時(shí)，MT分泌減少，暗期時(shí)，MT分泌增加[18]。MT具有抑制促性腺激素釋放的功能，性腺的發(fā)育和功能活動因此受到抑制。光照刺激雞視網(wǎng)膜感受器會導(dǎo)致視網(wǎng)膜處5-羥色胺分泌增加，5-羥色胺是MT的前體物質(zhì)，經(jīng)一系列酶的催化作用后產(chǎn)生MT，進(jìn)而導(dǎo)致相關(guān)生殖激素基因mRNA表達(dá)量下調(diào)和激素分泌下降[19]。除此之外，四季更替，MT分泌水平也相應(yīng)變化，對調(diào)節(jié)禽類行為的季節(jié)性變化具有重要意義[20]。

2 光照節(jié)律對各階段雞繁殖性能的影響

從單細(xì)胞到人類，所有生命活動均按照一定規(guī)律運(yùn)行，且具有周期性活動現(xiàn)象，這種現(xiàn)象稱之為生物節(jié)律[21-22]。視網(wǎng)膜上黑視蛋白感受外界明暗變化后，由視網(wǎng)膜神經(jīng)節(jié)細(xì)胞將信息通過視網(wǎng)膜下丘腦束傳遞至視交叉上核（superchiasmatic nucleus，SCN），SCN通過調(diào)控生物鐘基因的周期性振蕩表達(dá)產(chǎn)生生物節(jié)律信號。最終，經(jīng)節(jié)律輸出系統(tǒng)傳遞至外周的生物節(jié)律信號，與外周器官內(nèi)源性生物鐘系統(tǒng)協(xié)同作用維持機(jī)體的生理活動，包括對體能變化、精神活動和情緒波動等影響[23-27]?？梢姼黝惿砉δ艿墓?jié)律在于保證機(jī)體健康的生命活動[28]。光照節(jié)律包括對光照和黑暗時(shí)長的控制，促進(jìn)機(jī)體生物節(jié)律的形成。種雞和蛋雞的生產(chǎn)周期較長，不同生長階段的生理特點(diǎn)差異較大。所以，雞在不同的生長階段采用不同的光照節(jié)律。

2.1 育成階段光照節(jié)律

雞在育成期階段，生長迅速、發(fā)育旺盛。育成階段的質(zhì)量將間接影響產(chǎn)蛋期繁殖性能[29]。生產(chǎn)中，人們普遍關(guān)注體重和脂肪沉積等是否達(dá)標(biāo)，而易忽視光照變化對性腺發(fā)育的影響。由于雞12周齡后性腺發(fā)育很快，并對光照時(shí)間長短反應(yīng)敏感，如不限制光照，會引起性早熟等情況[30]。

半開放雞舍飼養(yǎng)時(shí)，雞逆季、順季飼養(yǎng)所采用的漸增或漸減光照模式會導(dǎo)致兩者性成熟時(shí)間相差一個(gè)月。研究表明，與漸增或漸減的自然光照相比，AA種雞育成期采取8或9 h的恒定光照能提高受精率[31]。IDRIS等[32]研究發(fā)現(xiàn)，Indian River雞采用8 h的恒定光照比漸減和漸增自然光照開產(chǎn)早；在密閉式飼養(yǎng)環(huán)境中，育成期8 h恒定光照組的開產(chǎn)和產(chǎn)蛋高峰時(shí)間早于長光照組13.5 h，且產(chǎn)蛋率也顯著提高。呂錦芳等[33-34]發(fā)現(xiàn)，蛋雞育成期接受13 h長光照處理，雖然19周齡時(shí)的卵巢指數(shù)顯著高于8 h的短光照組，但開產(chǎn)后的雞群-Ⅰ的mRNA表達(dá)豐度顯著低于育成期短光照組。黃羽種雞的研究中也發(fā)現(xiàn)，育成期采取恒定8 h光照，其產(chǎn)蛋后期的、和，以及LH和FSH激素水平均高于10 h或12 h光照，且恒定8 h光照的產(chǎn)蛋高峰維持時(shí)間更長[35]。蛋雞育成期保持6或8 h恒定光照，可使開產(chǎn)后產(chǎn)蛋率上升更快[36]。但PETER等[37]研究發(fā)現(xiàn)，白來航雞育成期6、9和12 h恒定光照并不影響性成熟時(shí)間和產(chǎn)蛋量。綜上，育成期光照時(shí)長低于6 h或高于10 h均會影響雞的產(chǎn)蛋潛力。因此，應(yīng)保證育成雞維持8—9 h的光照時(shí)長以保證體況和體重在性成熟時(shí)達(dá)標(biāo)，提高繁殖潛力。

很多情況下，公母雞混養(yǎng)會導(dǎo)致公雞無法接受到最適宜的光照節(jié)律。隨著精確管理和生產(chǎn)，種公雞逐步被單籠飼養(yǎng)，光照對種公雞繁殖性能的影響也逐漸受到重視[38]。研究表明，肉用種公雞在育成期每天接受4或8 h恒定光照，其性成熟最快，睪丸重和精液量也優(yōu)于其他處理組[39]。YALCIN等[40]研究發(fā)現(xiàn)，4 h恒定光照會延遲種公雞性成熟，但對精液量和精子密度無顯著影響。SUN等[41]研究發(fā)現(xiàn)，黃羽肉種雞在先減后增的變程光照節(jié)律下飼養(yǎng)，其睪丸重、雞冠大小和睪酮水平都顯著高于連續(xù)光照和間歇光照節(jié)律。

上述研究表明，育成期恒定短光照是保證雞對光照刺激具有良好反應(yīng)能力的基礎(chǔ)。同時(shí)，公母雞的生理結(jié)構(gòu)和種用方向不同，育成期飼養(yǎng)管理中的光環(huán)境控制應(yīng)差異化對待。

2.2 產(chǎn)蛋階段光照節(jié)律

光照不僅使雞看到飲水和飼料，保障其生長發(fā)育，而且對繁殖有決定性的刺激作用，即對雞的性成熟、排卵和產(chǎn)蛋等均有重要影響。在現(xiàn)代集約化飼養(yǎng)中，通過人為控光，能提高群體開產(chǎn)整齊度，延長產(chǎn)蛋高峰期。因此，光照刺激周齡的選擇，以及產(chǎn)蛋期光照時(shí)長和強(qiáng)度控制，是產(chǎn)蛋雞飼養(yǎng)管理的關(guān)鍵技術(shù)點(diǎn)，相關(guān)研究也較多，尤其是肉種雞。

2.2.1 光照刺激周齡 光照刺激必須在恰當(dāng)?shù)碾A段實(shí)施才可以有效發(fā)揮作用。DUNN等[42]研究發(fā)現(xiàn)，種雞3周齡時(shí)下丘腦對光照刺激具有反應(yīng)。若種雞缺少光照刺激則會顯著延遲性成熟和開產(chǎn)[43]。IDRIS等[32]研究光照刺激時(shí)間對Indian River種雞的影響，發(fā)現(xiàn)與14和16周齡光照刺激相比，18周齡接受光照刺激的種雞，開產(chǎn)日齡雖晚于各組，但產(chǎn)蛋數(shù)最多。YUAN等[44]也發(fā)現(xiàn)，20周齡光照刺激的Acian Farm肉種雞開產(chǎn)日齡顯著晚于14和17周齡，但各組間產(chǎn)蛋數(shù)無顯著差異。石雷等[45]發(fā)現(xiàn)AA種雞在16周齡光照刺激時(shí)開產(chǎn)日齡顯著延遲；隨著光照刺激時(shí)間的推遲，光照刺激至開產(chǎn)的間隔時(shí)間逐漸縮短。RENEMA等[46-49]在Starbro、Hubbard和Ross肉種雞上的研究結(jié)果與此一致。ZUIDHOF等[50]研究發(fā)現(xiàn)，Ross和Hubbard種雞18周齡光刺激組的產(chǎn)蛋數(shù)雖顯著高于22周齡光刺激組，但其小蛋數(shù)目較多，合格蛋數(shù)低于22周齡光刺激組，且22周齡光照刺激的孵化率高于18周齡。同時(shí)，RENEMA等[46]發(fā)現(xiàn)，18周齡光照刺激還會導(dǎo)致群體等級制度增強(qiáng)，使雞處于不穩(wěn)定的排卵狀態(tài)。SILVERSIDES等[51]在蛋種雞中發(fā)現(xiàn)，20周齡光刺激組的開產(chǎn)時(shí)間晚于18周齡。

種雞體成熟前進(jìn)行過早的光照刺激致使體況發(fā)育停止，換為產(chǎn)蛋期飼料后營養(yǎng)用于生產(chǎn)儲備和脂肪沉積，從而導(dǎo)致性腺發(fā)育和雌激素增長緩慢。雖個(gè)別體況較佳，性成熟提前，但大部分個(gè)體體況變差，致使開產(chǎn)整齊度變差。光照刺激數(shù)周后，即使達(dá)到體成熟，雞群也處于光失敏狀態(tài)，即對光照刺激不再具有反應(yīng)能力，因此性成熟明顯延遲。YUAN等[44]研究早期光照和體重對種雞生產(chǎn)性能的影響，發(fā)現(xiàn)體重偏大的種雞，早光照刺激會促進(jìn)開產(chǎn)，但沒有提高群體總產(chǎn)蛋數(shù)。其原因主要是肉種雞限飼過程中，體重偏大的雞群器官發(fā)育也較快，光照刺激后有利于生殖器官的發(fā)育，但超重的體況和過多的腹脂對繁殖性能產(chǎn)生不利影響。ROBINSON等[47]研究發(fā)現(xiàn)，光照刺激對種雞性成熟前的卵巢重、肝臟重、腹脂重和胸肌重影響顯著，但該差異在性成熟后即消失。MELNYCHUK等[52]研究發(fā)現(xiàn)，在24周齡接受光照刺激的Cobb種雞性成熟時(shí)的輸卵管和肝臟更重，腹脂較多。但ROBINSON等[53]以Ross和Hubbard種雞為對象，發(fā)現(xiàn)光照刺激起始時(shí)間（18周齡和22周齡）對性成熟時(shí)的胸肌重沒有顯著影響，且18周齡光照刺激組的輸卵管重和卵巢重也顯著大于22周齡。

有研究表明，提前性成熟會導(dǎo)致蛋殼質(zhì)量下降以及閉鎖卵泡發(fā)生率增加，排卵間隔時(shí)間延長，從而導(dǎo)致大黃卵泡數(shù)減少[54-55]。RENEMA等[46]研究發(fā)現(xiàn)，22周齡光刺激組的初產(chǎn)蛋重顯著高于18周齡。光照刺激時(shí)間對雞產(chǎn)蛋中后期的平均蛋重影響較小[44, 47, 49]。SILVERSIDES等[51]研究發(fā)現(xiàn)，蛋雞20周齡光刺激的蛋殼重高于18周齡。ZUIDHOF等[50]以Ross和Hubbard種雞為對象，發(fā)現(xiàn)光照刺激時(shí)間對產(chǎn)蛋初期軟殼蛋數(shù)和蛋殼畸形蛋數(shù)存在影響。

生產(chǎn)中，除了保證雞的體重在性成熟時(shí)達(dá)標(biāo)外，胸肌、腹脂和肝臟重量等也作為雞體成熟的重要指標(biāo)。光照刺激前均需測量胸肌發(fā)育和腹脂沉積，進(jìn)而估計(jì)雞群體況發(fā)育。從卵黃的形成和主要成分來看，卵黃沉積主要在排卵前的10 d左右進(jìn)行。高產(chǎn)雞每產(chǎn)一枚蛋，肝臟每天需要合成19 g卵黃前體，卵黃前體經(jīng)血液輸送到發(fā)育的卵泡，通過特異性受體介導(dǎo)在卵黃中。卵黃中65%的固體成分為脂蛋白復(fù)合體（即極低密度脂蛋白），脂蛋白復(fù)合體中12%是蛋白質(zhì)，而88%為脂類，較高的可以隨時(shí)動用的脂類也是母雞沉積一定量體脂有利于開產(chǎn)和持續(xù)產(chǎn)蛋的原因[43, 56, 57]。RENENMA等[46]發(fā)現(xiàn)，種雞22周齡光刺激的腹脂率顯著高于18周齡。但PISHNAMAZI等[49]和ROBINSON等[47, 58]并未發(fā)現(xiàn)光照刺激時(shí)間對雞腹脂率存在影響。對于黃羽種雞的光照刺激時(shí)間的相關(guān)研究還鮮有報(bào)道，生產(chǎn)中多參照蛋雞的光照刺激時(shí)間，即在18周齡進(jìn)行光照刺激。

種母雞通過光照可以提早性成熟，但生產(chǎn)實(shí)踐中需要慎重使用，因?yàn)檫m時(shí)和整齊開產(chǎn)才會利于群體整體繁殖性能的發(fā)揮，以及便于管理。

種公雞性早熟在實(shí)際生產(chǎn)中具有重要作用，尤其是在人工輸精時(shí)可以獲得更多的精液。TYLER等[59]研究Ross種公雞分別在8、11、14、17、21和23周齡光照刺激對其繁殖性能的影響，發(fā)現(xiàn)各處理性成熟時(shí)間無顯著差異，第一次產(chǎn)生精液的時(shí)間均在164—172 日齡；14周齡后，公雞對光照刺激存在反應(yīng)，且隨著光照刺激的推遲，睪丸發(fā)育也推遲，這一趨勢與母雞相似，但公雞的性成熟時(shí)間早于母雞。研究表明，種公雞8周齡接受光照刺激，能夠產(chǎn)生精液并有雞冠發(fā)育的公雞，與沒有發(fā)現(xiàn)相關(guān)變化的公雞對比，其后代母雞的性成熟時(shí)間更早，后代公雞的睪丸發(fā)育更快，且這一效果在肉種雞中更為明顯[60]。實(shí)際生產(chǎn)中，種用公母雞多混養(yǎng)接受相同光照，以至于公雞繁殖性能的光調(diào)控機(jī)制和應(yīng)用研究相對較少。隨著人工輸精、精液稀釋和存儲以及種公雞隔代利用等技術(shù)的應(yīng)用和發(fā)展，有必要對公雞的光照調(diào)控機(jī)制和相關(guān)技術(shù)開展系統(tǒng)性研究。

2.2.2 光照時(shí)長 雞進(jìn)入產(chǎn)蛋期后，光照節(jié)律則由恒定短光照轉(zhuǎn)變?yōu)楹愣ㄩL光照。長光照的時(shí)長選擇也是提高雞繁殖性能的關(guān)鍵控制點(diǎn)之一。將雞從8L:16D的光照轉(zhuǎn)變?yōu)?0.5L: 13.5D或12.75L:11.25D的光照，血漿LH均會成比例增加[61]。LEWIS等[62]研究Cobb種雞產(chǎn)蛋期光照時(shí)長與LH響應(yīng)曲線，發(fā)現(xiàn)在20周齡時(shí)給予9.5 h的光照刺激，LH水平開始上升；每天11.5 h光照時(shí)長的LH水平上升速度最快，13 h時(shí)曲線趨于平穩(wěn)。而GOW等[63]研究發(fā)現(xiàn)，光照刺激不會影響血漿LH的變化。黃仁錄等[64]以海蘭褐蛋雞為研究對象，發(fā)現(xiàn)激素分泌規(guī)律性并不和光照周期（時(shí)長）呈正相關(guān)，11L:13D光照組在產(chǎn)蛋高峰期FSH和LH峰值含量最高；在產(chǎn)蛋期階段，隨著光照時(shí)長增加，血糖濃度也增高[65]；17L:7D的長光照使雞群體內(nèi)蛋白合成代謝旺盛，增強(qiáng)機(jī)體免疫功能，有利于雞群產(chǎn)蛋后期生產(chǎn)性能的發(fā)揮[66]。王翠菊等[67]研究發(fā)現(xiàn)，海蘭褐蛋雞產(chǎn)蛋期維持13L:11D光照，其產(chǎn)蛋后期的子宮部皺襞長而復(fù)雜，分布較緊密，輸卵管重最大。潘棟等[68]研究發(fā)現(xiàn)，海蘭褐雞產(chǎn)蛋期17L:7D光照組的產(chǎn)蛋率最高。CHEN等[69]研究發(fā)現(xiàn)，蛋雞產(chǎn)蛋期17L:7D光照組的開產(chǎn)日齡早于11L:13D光照組5.7 d，但過長或過短光照時(shí)長都會一定程度限制卵巢發(fā)育。

肉種雞與蛋雞體況差異較大，且肉種雞多存在光照不應(yīng)性情況，因此肉種雞產(chǎn)蛋期光照時(shí)長短于蛋雞。LEWIS等[70]發(fā)現(xiàn)，Ross種雞產(chǎn)蛋期14 h光照時(shí)長的性成熟早于11 h光照時(shí)長，破蛋率也較低，且各處理產(chǎn)蛋量差異不顯著。LEWIS等[71]以Cobb肉種雞為研究對象，發(fā)現(xiàn)產(chǎn)蛋期光照時(shí)長≤14 h時(shí)，隨著光照時(shí)長增加，開產(chǎn)時(shí)間提前，產(chǎn)蛋量增加。不同增光方式對肉種雞生產(chǎn)性能沒有顯著影響；與光照時(shí)長11、12和14 h相比，產(chǎn)蛋期維持13 h光照時(shí)長，其飼料轉(zhuǎn)化率最高，破蛋和臟蛋率低[72]。

Floyd等[73]研究發(fā)現(xiàn)，Cobb種公雞20周齡后維持8、9、9.5、10、10.5、11、11.5、12、12.5、13、14或18 h光照時(shí)長對性成熟、雞冠面積和正常精子活力均無顯著影響，但維持8—11 h區(qū)間的光照時(shí)長，其精子密度最高，隨著光照時(shí)長的增加，精子濃度逐漸降低；睪丸重量隨著光照時(shí)長的增加也逐漸降低。

綜上，母雞產(chǎn)蛋期需要較長的光照時(shí)間以促進(jìn)其產(chǎn)蛋，而種公雞采取同母雞產(chǎn)蛋期一致的光照時(shí)長可能會降低精液品質(zhì)，種公雞或許并不適合超過13 h的光照管理。

2.3 非自然光照節(jié)律

在種雞和蛋雞生產(chǎn)中，通常采用24 h光照制度，即一晝夜光照與黑暗各占一定時(shí)數(shù)所形成的明暗周期。長于或短于24 h的光照制度，稱為非自然光照節(jié)律。研究最多的是27或28 h光照制度。以往數(shù)據(jù)顯示，雞的排卵-產(chǎn)蛋周期為25—27 h。在一個(gè)連產(chǎn)序列中，產(chǎn)蛋時(shí)間會逐步后移，因?yàn)楫a(chǎn)蛋時(shí)間上的嚴(yán)格偏好，當(dāng)產(chǎn)蛋時(shí)間后移至下午時(shí)，就會造成連產(chǎn)的中斷，在一天或者數(shù)天的間歇后再開始一個(gè)新的產(chǎn)蛋序列[6]。非自然光照節(jié)律的提出，使母雞的繁殖節(jié)律在此光照節(jié)律下能夠得到較好的同步，更接近蛋的形成時(shí)間。蛋在輸卵管內(nèi)的停留時(shí)間延長會提高蛋重，減少破損蛋和畸形蛋的發(fā)生率[74]。PROUDFOOT[75]研究發(fā)現(xiàn)，27和24 h兩種光照節(jié)律及其對應(yīng)的間歇光照制度對種雞性成熟、產(chǎn)蛋數(shù)和飼料轉(zhuǎn)化率沒有影響，但27 h光照節(jié)律時(shí)形成的蛋偏大，且地板蛋較多。HAWES等[76]研究發(fā)現(xiàn)，蛋雞采用26 h光照節(jié)律的產(chǎn)蛋率比24 h光照節(jié)律低，但能增加蛋重。SPIES等[77]以Shaver Starbro種雞為對象，發(fā)現(xiàn)28 h光照節(jié)律在產(chǎn)蛋前期（30周齡）產(chǎn)蛋間隔時(shí)間更長，蛋重更大，蛋殼重量顯著增加；24 h光照制度能夠增加卵巢和輸卵管重量，產(chǎn)生更多的大卵泡；兩種光照節(jié)律在產(chǎn)蛋數(shù)方面沒有差異。WATERS等[78]研究發(fā)現(xiàn)，自然與非自然光照節(jié)律對Warren雞的蛋重?zé)o顯著影響。BOERSMA等[79]發(fā)現(xiàn)種雞產(chǎn)蛋后期（47周齡）采用28 h光照節(jié)律雖然能增加蛋重，但產(chǎn)蛋量下降快，合格蛋降低，蛋殼質(zhì)量下降。

綜上，非自然光照節(jié)律可以提高蛋重，減少破蛋率和畸形率，但蛋重的增加可能多由于蛋殼重量增加，而且28 h光照節(jié)律可能導(dǎo)致后期產(chǎn)蛋數(shù)下降。非自然光照節(jié)律不符合歐盟規(guī)定動物福利標(biāo)準(zhǔn)[80]，與飼養(yǎng)人員的正常作息時(shí)間不一致，在實(shí)際生產(chǎn)中并未廣泛應(yīng)用，但是研究非自然光照節(jié)律對了解家禽的生物節(jié)律具有一定的科學(xué)意義。

2.4 光照不應(yīng)性

光照不應(yīng)性指家禽對最初誘導(dǎo)或維持其生產(chǎn)性能的光照節(jié)律無反應(yīng)的特性[81]。隨著光照的延長，光子能傳遞到神經(jīng)系統(tǒng)的信號逐漸減少，最后禽類不能維持最高濃度的促性腺激素水平。在大多數(shù)雞中，光照不應(yīng)性的主要特點(diǎn)是雞在最初產(chǎn)蛋的12—15個(gè)月期間產(chǎn)蛋量逐漸減少。隨著產(chǎn)蛋的減少，垂體逐漸不能對GnRH發(fā)生反應(yīng)而釋放LH或FSH，有時(shí)促性腺激素也會降低到不能維持性腺機(jī)能的程度，卵巢在光照刺激后10周左右退化[82-84]。

雞光照管理較為復(fù)雜，母雞會對長白天的光照反應(yīng)變?nèi)?。光照不?yīng)性晚于光照刺激出現(xiàn)，會使雞產(chǎn)蛋量逐步下降。而光照不應(yīng)性的早晚與開產(chǎn)前光照時(shí)長緊密相關(guān)。為使雞的光照不應(yīng)性情況減緩，可首先通過較短但具有刺激作用的光照時(shí)長對開產(chǎn)前的雞進(jìn)行光照刺激，從而使母雞的繁殖性能保持穩(wěn)定。光照不應(yīng)性這一情況多在肉種雞中發(fā)生，而在蛋雞生產(chǎn)中已經(jīng)不存在[85]。因此，與蛋雞產(chǎn)蛋期光照時(shí)長16 h或17 h相比，肉種雞多為14或15 h。

光照不應(yīng)性使種雞繁殖具有季節(jié)性，在較適宜的季節(jié)孵化種蛋，最大限度提高雛禽的存活率[55, 86]。SHARP等[84]研究發(fā)現(xiàn)，種雞產(chǎn)蛋中期再次增加光照時(shí)長對其生產(chǎn)性能沒有影響。TYLE等[85]以種公雞為對象，在40周齡設(shè)置不同光照時(shí)長的光照刺激，發(fā)現(xiàn)隨著光照刺激時(shí)長增加，加速了種公雞光照不應(yīng)性的出現(xiàn)，睪丸重和睪酮水平也下降。出現(xiàn)光照不應(yīng)性的母雞一直到接受短光照處理后10—12周才可再次用光刺激，消除光照不應(yīng)性。在生產(chǎn)實(shí)踐中，多將短光照和強(qiáng)制換羽等措施結(jié)合，使產(chǎn)蛋后期母雞下丘腦得到一定程度的休息，從而可再次接受光照刺激，出現(xiàn)對光照的反應(yīng)[87]。

3 孵化期光照對種蛋孵化效率及后期生產(chǎn)性能的影響

種蛋孵化期的環(huán)境控制對胚胎發(fā)育至關(guān)重要。孵化期光照條件通常不被重視，而越來越多的研究指出，孵化期光照刺激對于種蛋的孵化性能以及雛雞的生產(chǎn)性能有一定影響。發(fā)育中的雞胚呈蜷縮狀，頭轉(zhuǎn)向一側(cè)，喙埋入翼下，一側(cè)眼睛對光照條件更為敏感，從而導(dǎo)致胚胎的不對稱發(fā)育[88]。孵化期光照刺激能夠提高種蛋的孵化率[89-90]和出雛后的應(yīng)激能力[9]，且胚胎期綠光刺激能夠顯著提高肉雞和火雞的肌肉增長速度[91-94]。但也有研究發(fā)現(xiàn)，雞孵化期間光照會對其產(chǎn)生負(fù)面影響。TAMIMIE等[95]發(fā)現(xiàn)白來航種蛋孵化期間給予光照會增加死胚率、延長出雛時(shí)間和降低出雛重。AIGEGIL等[96]發(fā)現(xiàn)，孵化期間白光刺激洛島紅雞會提高死胚率，導(dǎo)致胚胎發(fā)育延緩，肝臟腫大。ARCHER等[97]研究發(fā)現(xiàn)，孵化期間給予肉雞光照會造成眼睛重量降低和不對稱性增加。因此，關(guān)于孵化期間光照刺激效應(yīng)的研究結(jié)果尚不一致，有待進(jìn)一步探索。

4 結(jié)語

作為家禽生長繁殖極為重要的環(huán)境調(diào)節(jié)因素，光照方面的研究仍需重視。光調(diào)控技術(shù)對各階段產(chǎn)蛋雞均有顯著影響，生產(chǎn)上已被廣泛應(yīng)用，但是具體作用機(jī)制尚不明確，如性別對光照環(huán)境變化是否存在差異化反應(yīng)，各個(gè)光感受器的在介導(dǎo)光-繁殖生理反應(yīng)過程中的協(xié)同和拮抗關(guān)系，以及光環(huán)境引起的表觀遺傳學(xué)修飾及其可遺傳性尚有待于進(jìn)一步深入研究。

[1] DAWSON A, KING V M, BENTLEY G E, BALL G F. Photoperiodic control of seasonality in birds., 2001, 16(4): 365-380.

[2] 陳耀星, 王子旭, 內(nèi)藤順平, 雞投射視頂蓋視網(wǎng)膜節(jié)細(xì)胞的形態(tài)學(xué)分類. 解剖學(xué)報(bào), 2002，33(1): 47-50.

CHEN Y X, WANG Z X, MEITENG S G. Morphological classification of retinotectal ganglion cells in the chick retina., 2002, 33(1): 47-50. (in Chinese)

[3] LEWIS P D, Morris T R, Poultry and colored light., 2000, 56(3): 189-207.

[4] RENEMA R A, SIKUR V R, ROBINSON F E, KORVER D R, ZUIDHOF M J. Effects of Nutrient Density and Age at Photostimulation on Carcass Traits and Reproductive Efficiency in Fast- and Slow-Feathering Turkey Hens., 2008, 87(9): 1897-1908.

[5] LEWIS P D, CIACCIARIELLO M, CICCONE N A, SHARP P J, GOUS R M. Lighting regimens and plasma LH and FSH in broiler breeders., 2005, 46(3): 349-353.

[6] MOORE R Y, SPEH J C, LEAK R K. Suprachiasmatic nucleus organization., 2002, 309(1): 89-98.

[7] GILLETTE M U, TISCHKAU S A. Suprachiasmatic nucleus: the brain's circadian clock., 1999, 54(1): 33-58.

[8] SURBHI, KUMAR V. Avian photoreceptors and their role in the regulation of daily and seasonal physiology.2015, 220: 13-11.

[9] BOWMAKER J K, DARTNALL H J. Visual pigments of rods and cones in a human retina., 1980, 298(1): 501-511.

[10] KUENZEL W J. The search for deep encephalic photoreceptors within the avian brain, using gonadal development as a primary indicator., 1993, 72(5): 959-967.

[11] HARRISON P C. Extraretinal photocontrol of reproductive responses of Leghorn hens to photoperiods of different length and spectrum., 1972, 51(6): 2060-2064.

[12] OLIVER J, BAYLé J D. Brain photoreceptors for the photo-induced testicular response in birds., 1982, 38(9): 1021-1029.

[13] SALDANHA C J, SILVERMAN A J, SILVER R. Direct innervation of GnRH neurons by encephalic photoreceptors in birds., 2001, 16(1): 39-49.

[14] MOBARKEY N, AVITAL N, HEIBLUM R,ROZENBOIM I. The role of retinal and extra-retinal photostimulation in reproductive activity in broiler breeder hens., 2010, 38(4): 235-243.

[15] UNDERWOOD H, MENAKER M. Photoperiodically significant photoreception in sparrows: is the retina involved?, 1970, 167(3916): 298-301.

[16] RATHINAM T, KUENZEL W J. Attenuation of gonadal response to photostimulation following ablation of neurons in the lateral septal organ of chicks., 2005, 64(5): 455-461.

[17] KLEIN D C. The 2004 Aschoff/Pittendrigh lecture: Theory of the origin of the pineal gland a tale of conflict and resolution., 2004, 19(4): 264-279.

[18] BINKLEY S, STEPHENS J L, RIEBMAN J B, REILLY K B. Regulation of pineal rhythms in chickens: photoperiod and dark-time sensitivity., 1977, 32(4): 411-416.

[19] MOBARKEY N, AVITAL N, HEIBLUM R, ROZENBOIM I. The effect of parachlorophenylalanine and active immunization against vasoactive intestinal peptide on reproductive activities of broiler breeder hens photostimulated with green light., 2013, 88(4): 1-7.

[20] BENTLEY G E, VAN'T HOF T J, BALL G F. Seasonal neuroplasticity in the songbird telencephalon: a role for melatonin., 1999, 96(8): 4674-4679.

[21] 王艷利, 曲麗娜, 李瑩輝. 生物節(jié)律基因非編碼RNA調(diào)控機(jī)制. 中國生物化學(xué)與分子生物學(xué)報(bào), 2016, 32(4): 353-358.

WANG Y L, QU L N, LI Y H. Regulation of circadian gene by non-coding RNAs., 2016, 32(4): 353-358. (in Chinese)

[22] 邢陳, 顧曄, 宋倫. 晝夜節(jié)律在代謝調(diào)控中的作用. 軍事醫(yī)學(xué), 2017, 41(7): 618-622.

XING C, GU Y, SONG L. Function of circadian rhythms in regulation of metabolism., 2017, 41(7): 618-622. (in Chinese)

[23] 韓芳. 晝夜節(jié)律性睡眠障礙. 生命科學(xué), 2015, 27(11): 1448-1454.

HAN F. Circadian rhythm sleep disorders., 2015, 27(11): 1448-1454. (in Chinese)

[24] HASTINGS M H, REDDY A B, MAYWOOD E S. A clockwork web: circadian timing in brain and periphery, in health and disease., 2003, 4(8): 649-661.

[25] PANDA S. Multiple photopigments entrain the mammalian circadian oscillator., 2007, 53(5): 619-621.

[26] ALBRECHT U. Timing to perfection: the biology of central and peripheral circadian clocks., 2012, 74(2): 246-260.

[27] MOHAWK J A, GREEN C B, TAKAHASHI J S. Central and peripheral circadian clocks in mammals., 2012, 35(1): 445-462.

[28] 陳思禹, 錢近春, 劉暢. 代謝生物鐘研究進(jìn)展. 生命科學(xué), 2015(11): 1409-1417.

CHEN S Y, QIAN J C, LIU C. The molecular mechanism for the integration of circadian clock and energy metabolism., 2015, 27(11): 1409-1417. (in Chinese)

[29] 楊寧. 家禽生產(chǎn)學(xué). 北京: 中國農(nóng)業(yè)出版社, 2002.

YANG N.. Beijing: China Agriculture Press, 2002. (in Chinese)

[30] Hassanzadeh M, Fard M H, Buyse J, DECUYPERE E. Beneficial effects of alternative lighting schedules on the incidence of ascites and on metabolic parameters of broiler chickens., 2003, 51(4): 513-520.

[31] BRAKE J, GARLICH J D, BAUGHMAN G R. Effects of lighting program during the growing period and dietary fat during the laying period on broiler breeder performance., 1989, 68(9): 1185-1192.

[32] IDRIS A A, ROBBINS K R. Light and feed management of broiler breeders reared under short versus natural day length., 1994, 73(5): 603-609.

[33] 呂錦芳, 饒開晴, 姜錦鵬, 倪迎冬, 顧有方, 寧康健, 應(yīng)如海, 周玉剛, 許百年. 光周期對蛋雞GnRH-I,GnRH-Ra mRNA表達(dá)和卵巢發(fā)育的影響. 激光生物學(xué)報(bào), 2015, 24(3): 251-256.

Lü J F, RAO K Q, JIANG J P, NI Y D, GU Y F, NING K J, YING R H, ZHOU Y G, XU B N. Effects of photoperiods on GnRH-I, GnRH-Ra mRNA expression and ovary development in layers., 2015, 24(3): 251-256. (in Chinese)

[34] 呂錦芳, 倪迎冬, 寧康健, 趙茹茜, 陳杰, 金光明. 不同光周期下ISA褐蛋雞松果腺GnRH-Ⅰ mRNA表達(dá)的變化. 中國獸醫(yī)學(xué)報(bào), 2009(3): 335-338.

Lü J F, NI Y D, NING K J, ZHAO R X, CHEN J, JIN G M. Change of GnRH-I mRNA expression in pineal gland for ISA brown layers at different photoperiods., 2009(3): 335-338. (in Chinese)

[35] Han S, Wang Y, Liu L, Li D, Liu Z, Shen X, Xu H, Zhao X, Zhu Q, Yin H. Influence of three lighting regimes during ten weeks growth phase on laying performance, plasma levels- and tissue specific gene expression of reproductive hormones in Pengxian yellow pullets., 2017, 12(5): 1-11.

[36] LEWIS P D, CASTON L, LEESON S. Rearing photoperiod and abrupt versus gradual photostimulation for egg-type pullets., 2007, 48(3): 276-283.

[37] LEWIS P D, CASTON L, LEESON S. Influence of rearing photoperiod and age and mode of transfer to final photoperiod on performance in egg-type pullets., 2009, 8(1): 7-13.

[38] 孫研研, 陳繼蘭. 種公禽繁殖系統(tǒng)對光要素的應(yīng)答機(jī)制研究進(jìn)展. 中國畜牧獸醫(yī), 2017, 44(9): 2692-2698.

SUN Y Y, CHEN J L. Research progress on mechanisms of lighting affecting the reproduction of male poultry breeders., 2017, 44(9): 2692-2698. (in Chinese)

[39] RENDEN J A, OATES S S, WEST M S. Performance of two male broiler breeder strains raised and maintained on various constant photoschedules., 1991, 70(7): 1602-1609.

[40] YALCIN S, MCDANIEL G R, WONGVALLE J. Effect of preproduction lighting regimes on reproductive performance of broiler breeders., 1993, 2(2): 51-54.

[41] SUN Y Y, TANG S, CHEN Y, CHEN J L. Effects of light regimen and nutrient density on growth performance, carcass traits, meat quality, and health of slow-growing broiler chickens., 2017, 198: 201-208.

[42] DUNN I C, SHARP P J, HOCKING P M. Effects of interactions between photostimulation, dietary restriction and dietary maize oil dilution on plasma LH and ovarian and oviduct weights in broiler breeder females during rearing., 1990, 31(2): 415-427.

[43] LUPICKI, EWA M. Ovarian morpohology and steroidogenesis in domestic fowl (Gallus domesticus) [microform]: effects of aging, strain, photostimulation program and level of feeding., 1994.

[44] YUAN T, LIEN R J, MCDANIEL G R. Effects of increased rearing period body weights and early photostimulation on broiler breeder egg production., 1994, 73(6): 792-800.

[45] 石雷, 孫研研, 許紅, 劉一帆, 徐松山, 李云雷, 葉建華, 陳超, 李冬立, 陳余, 郭艷麗, 陳繼蘭. 光照刺激時(shí)間對肉種雞性成熟的影響. 畜牧獸醫(yī)學(xué)報(bào), 2017, 48(11): 2107-2114.

SHI L, SUN Y Y, XU H, LIU Y F, XU S S, LI Y L, YE J H, CHEN C, LI D L, CHEN Y, GUO Y L, CHEN J L. Effect of age at photostimulation on sexual maturation in broiler breeders., 2017, 48(11): 2107-2114. (in Chinese)

[46] RENEMA R A, ROBINSON F E, ZUIDHOF M T, Reproductive efficiency and metabolism of female broiler breeders as affected by genotype, feed allocation, and age at photostimulation. 2. Sexual maturation., 2007, 86(10): 2267-2277.

[47] ROBINSON F E WAUTIER T A HARDIN R T, ROBINSON N A, WILSON J L, NEWCOMBE M, MCKAY R I. Effects of age at photostimulation on reproductive efficiency and carcass characteristics. 1. Broiler breeder hens., 1996, 3(76): 275-282.

[48] LEWIS P D, CIACCIARIELLO M, BACKHOUSE D, GOUS R M. Effect of age and body weight at photostimulation on the sexual maturation of broiler breeder pullets transferred from 8L:16D to 16L:8D., 2007, 48(5): 601-608.

[49] PISHNAMAZI A, RENEMA R A, ZUIDHOF M J, ROBINSON F. Effect of age at photostimulation on sexual maturation in broiler breeder pullets., 2014, 93(5): 1274-1281.

[50] ZUIDHOF M J, RENEMA R A, ROBINSON F E. Reproductive efficiency and metabolism of female broiler breeders as affected by genotype, feed allocation, and age at photostimulation. 3. Reproductive efficiency., 2007, 86(10): 2278-2286.

[51] SILVERSIDES F G, KORVER D R, BUDGELL K L. Effect of strain of layer and age at photostimulation on egg production, egg quality, and bone strength., 2006, 85(7): 1136-1144.

[52] MELNYCHUK V L, KIRBY J D, KIRBY Y K, EMMERSON D A, ANTHONY N B. Effect of strain, feed allocation program, and age at photostimulation on reproductive development and carcass characteristics of broiler breeder hens., 2004, 83(11): 1861-1867.

[53] ROBINSON F E, ZUIDHOF M J, RENEMA R A. Reproductive efficiency and metabolism of female broiler breeders as affected by genotype, feed allocation, and age at photostimulation. 1. Pullet growth and development., 2007, 86(10): 2256-2266.

[54] MORRIS T R, PERRY G C. A model for predicting the age at sexual maturity for growing pullets of layer strains given a single change in photoperiod., 2002, 138(4): 441-458.

[55] GOUS N C T R M, GOUS A R M. Photorefractoriness in avian species - could this be eliminated in broiler breeders?., 2012, 68(4): 645-650.

[56] JOSEPH N S, ROBINSON F E, RENEMA R A, ZUIDHOF M J. Responses of two strains of female broiler breeders to a midcycle increase in photoperiod., 2002, 81(6): 745-754.

[57] BORNSTEIN S, PLAVNIK I, LEV Y, Body weight and/or fatness as potential determinants of the onset of egg production in broiler breeder hens., 1984, 25(3): 323-341.

[58] ROBINSON F E, ZUIDHOF M J, RENEMA R A. Reproductive efficiency and metabolism of female broiler breeders as affected by genotype, feed allocation, and age at photostimulation. 1. Pullet growth and development., 2007, 86(10): 2256-2266.

[59] TYLER N C, GOUS R M. The effect of age at photostimulation of male broiler breeders on testes growth and the attainment of sexual maturity., 2009, 39(3): 169-175.

[60] TYLER N C, GOUS R M. Selection for early response to photostimulation in broiler breeders., 2011, 52(4): 517-522.

[61] FOLLETT B K, FOSTER R G, NICHOLLS T J. Photoperiodism in birds., 1985, 117: 93-105.

[62] LEWIS P D, TYLER N C, GOUS R M, DUNN I C, SHARP P J. Photoperiodic response curves for plasma LH concentrations and age at first egg in female broiler breeders., 2008, 109(1-4): 274-286.

[63] GOW C B, SHARP P J, CARTER N B, YOO B H. Comparisons of time intervals and plasma LH concentrations during the ovulatory cycle of broiler breeder hens maintained under either a 24 h light:dark cycle or continuous light., 1987, 28(1): 129-137.

[64] 黃仁錄, 陳輝, 邸科前, 張競乾, 李軍喬, 張振紅, 潘棟. 不同光照周期對蛋雞高峰期血液激素水平的影響. 畜牧獸醫(yī)學(xué)報(bào), 2008(3): 368-371.

HUANG R L, CHEN H, DI K Q, ZHANG J Q, LI J Q, ZHANG Z H, PAN D. Effect of different photoperiods on blood hormone of laying hens., 2008(3): 368-371. (in Chinese)

[65] 黃仁錄, 陳輝, 潘棟, 韓愛云, 邸科前, 郭云霞, 張振紅. 不同光照周期對蛋雞高峰期血液生化指標(biāo)的影響. 華北農(nóng)學(xué)報(bào), 2007(03): 168-171.

HUANG R L, CHEN H, PAN D, HAN A Y, DI K Q, GUO Y X, ZHANG Z H. Effect of different photoperiods on blood biochemical parameters of hens., 2007(03): 168-171. (in Chinese)

[66] 黃仁錄, 陳輝, 潘棟, 邸科前, 侯永剛. 不同光增方式和周期對蛋雞蛋品質(zhì)和血液生化指標(biāo)的影響. 中國畜牧雜志, 2007, 43(13): 52-55.

HUANG R L, CHEN H, PAN D, DI K Q, HOU Y G. Effect of different lighting increscent and photoperiod on egg characters and blood biochemical parameters of laying hen., 2007, 43(13): 52-55. (in Chinese)

[67] 王翠菊, 陳輝, 侯永剛, 王飛, 王洪芳, 黃仁錄. 不同光照周期下雞輸卵管比較形態(tài)學(xué)及蛋品質(zhì)的研究. 河北農(nóng)業(yè)大學(xué)學(xué)報(bào). 2009, 32(04): 88-91.

WANG C J, CHEN H, HOU Y G, WANG F, WANG H F, HUANG R L. Comparative morphological study on oviduct and egg quality in different photoperiod., 2009, 32(04): 88-91. (in Chinese)

[68] 潘棟. 光照周期對蛋雞卵巢輸卵管形態(tài)、生產(chǎn)性能及血液生化指標(biāo)的影響[D]. 保定: 河北農(nóng)業(yè)大學(xué), 2008.

PAN D. Effect of photoperiod on procreation morphology, production and haemal biochemical parameters[D]. Baoding: Agricultural University of Hebei, 2008. (in Chinese)

[69] CHEN H, HUANG R L, ZHANG H X, DI K Q, PAN D, HOU Y G. Effects of Photoperiod on Ovarian Morphology and Carcass Traits at Sexual Maturity in Pullets., 2007, 86(5): 917-920.

[70] LEWIS P D, DANISMAN R, GOUS R M. Photoperiods for broiler breeder females during the laying period., 2010, 89(1): 108-114.

[71] LEWIS P D, GOUS R M. Effect of final photoperiod and twenty-week body weight on sexual maturity and early egg production in broiler breeders., 2006, 85(3): 377-383.

[72] LEWIS P D, GOUS R M. Constant and changing photoperiods in the laying period for broiler breeders allowed normal or accelerated growth during the rearing period., 2006, 85(2): 321-325.

[73] FLOYD M H, TYLER N C. Photostimulation of male broiler breeders to different photoperiods., 2011, 41(2): 146-155.

[74] YANNAKOPOULOS A L. Effect of an ahemeral light cycle on yolk weight and relationship between egg weight and yolk weight late in the pullet year., 1985, 64(8): 1596-1598.

[75] PROUDFOOT F G. The effects of dietary protein levels, ahemeral light and dark cycles, and intermittent photoperiods on the performance of chicken broiler parent genotypes., 1980, 59(6): 1258-1267.

[76] HAWES R O, LAKSHMANAN N, KLING L J. Effect of ahemeral light:dark cycles on egg production in early photostimulated brown-egg pullets., 1991, 70(7): 1481-1486.

[77] SPIES A A, ROBINSON F E, RENEMA R A, FEDDES J J, ZUIDHOF M J, FITZSIMMONS R C. The effects of body weight and long ahemeral days on early production parameters and morphological characteristics of broiler breeder hens., 2000, 79(8): 1094-1100.

[78] WATERS C J, ROSE S P, BAMPTON P R. Production responses of laying hens to 28 h bright:dim light cycles using different light intensity ratios and a 24 h temperature regimen., 1987, 28(2): 207-212.

[79] BOERSMA S I, ROBINSON F E, RENEMA R A. The effect of twenty-eight-hour ahemeral day lengths on carcass and reproductive characteristics of broiler breeder hens late in lay., 2002, 81(6): 760-766.

[80] SANTé O M D L, L'ALIMENTATION U P. laying down minimum rules for the protection of chickens kept for meat production., 2007, 182(7): 19-28.

[81] TYLER N C, GOUS R M. Photorefractoriness in avian species – could this be eliminated in broiler breeders?, 2012, 68(04): 645-650.

[82] LEWIS P D, GOUS R M, MORRIS T R. Model to predict age at sexual maturity in broiler breeders given a single increment in photoperiod., 2007, 48(5): 625-634.

[83] FOLLETT B K, ROBINSON J E. Photoperiod and gonadotrophin secretion in birds., 1980, 59: 39-61.

[84] SHARP P J, DUNN I C, CEROLINI S. Neuroendocrine control of reduced persistence of egg-laying in domestic hens: evidence for the development of photorefractoriness., 1992, 94(1): 221-235.

[85] TYLER N C, LEWIS P D, GOUS R M. Reproductive status in broiler breeder males is minimally affected by a mid-cycle increase in photoperiod., 2011, 52(1): 140-145.

[86] SOCKMAN K W, WILLIAMS T D, DAWSON A, BALL G F. Prior experience with photostimulation enhances photo-induced reproductive development in female European starlings: a possible basis for the age-related increase in avian reproductive performance., 2004, 71(3): 979-986.

[87] 趙興緒. 家禽的繁殖調(diào)控. 北京: 中國農(nóng)業(yè)出版社, 2010.

ZHAO X X.Beijing: China Agriculture Press, 2010. (in Chinese)

[88] CIACCIARIELLO M, GOUS R M. A comparison of the effects of feeding treatments and lighting on age at first egg and subsequent laying performance and carcass composition of broiler breeder hens.2010, 46(2): 246-254.

[89] HUTH J C, ARCHER G S. Effects of LED lighting during incubation on layer and broiler hatchability, chick quality, stress susceptibility and post-hatch growth., 2015, 94(12): 3052-3058.

[90] ARCHER G S, SHIVAPRASAD H L, MENCH J A. Effect of providing light during incubation on the health, productivity, and behavior of broiler chickens., 2009, 88(1): 29-37.

[91] ROZENBOIM I, PIESTUN Y, MOBARKEY N, BARAK M, HOYZMAN A, HALEVY O. Monochromatic light stimuli during embryogenesis enhance embryo development and posthatch growth., 2004, 83(8): 1413-1419.

[92] HALEVY O, PIESTUN Y, ROZENBOIM I, YABLONKA- REUVENI Y. In ovo exposure to monochromatic green light promotes skeletal muscle cell proliferation and affects myofiber growth in posthatch chicks., 2006, 290(4): 1062-1070.

[93] ZHANG L, ZHANG H J, WANG J, WU S G, QIAO X, YUE H Y, YAO J H, QI G H. Stimulation with monochromatic green light during incubation alters satellite cell mitotic activity and gene expression in relation to embryonic and posthatch muscle growth of broiler chickens., 2014, 8(1): 86-93.

[94] ZHANG L, ZHANG H J, QIAO X, YUE H Y, WU S G, YAO J H, QI G H. Effect of monochromatic light stimuli during embryogenesis on muscular growth, chemical composition, and meat quality of breast muscle in male broilers., 2012, 91(4): 1026-1031.

[95] TAMIMIE H S, FOX M W. Effect of continuous and intermittent light exposure on the embryonic development of chicken eggs., 1967, 20(3): 793-796.

[96] AIGEGIL V, MURILLOFERROL N. Effects of white light on the pineal gland of the chick embryo., 1992, 7(1): 1-6.

[97] ARCHER G S, SHIVAPRASAD H L, MENCH J A. Effect of providing light during incubation on the health, productivity, and behavior of broiler chickens., 2009, 88(1): 29-37.

（責(zé)任編輯 林鑒非）

Research Progress on the Regulatory Mechanism of Lighting Schedule Affecting the Reproduction Performance of Chickens

SHI Lei, LI YunLei, SUN YanYan, CHEN JiLan

(Institute of Animal Science, Chinese Academy of Agricultural Sciences/Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Beijing 100193)

Light is an important environmental factor for the organism. Artificial lighting has been widely utilized in modern poultry production. The poultry is light-sensitive. Light regulates their growth, production, and reproduction, and therefore affects the production efficiency. Light has now been another important environmental factor for poultry industry besides temperature, humidity, and ventilation. As a classical model animal, the studies of the effects of light on chicken reproductive physiology and the underlying mechanism would be of scientific significance. The photoreception of poultry and the effects of light schedule on chicken sexual maturity and reproduction were summarized in this review. The research progress on ahemeral lighting schedule, photorefractory, and light management during eggs incubation was also included. This review aimed at providing better understanding the effect of light schedule on poultry reproduction and the underlying mechanism. Perceiving the lighting by photoreceptors including eyes (retina), the deep brain tissue, and the pineal gland, the poultry transfers the lighting information to biological signals and affect the neuroendocrine system, especially the hypothalamic-pituitary-gonadal axis to affect the growth and reproduction. The gonad of birds develops rapidly and shows sensibility for the lighting length during rearing period. Lighting length of too short or long may impede the development or accelerate sexual maturity. The studies showed that a constant light of 8 or 9 h might assure the body condition and potential of reproduction performance. The lighting schedule parameters during the laying period of poultry includes photostimulation and lighting length. Photostimulation must be applied at a right age to assure the concurrent sexual maturity. Because of limited researches in yellow-feathered laying hens, most often they follow the photostimulation strategy of high-producing hens or with slight delay of photostimulation age. Lighting length is also critical for the reproduction performance. Laying hens (breeders) need long lighting period to keep productive during the laying period. There are, however, many differences between broiler breeders and layer hens (breeders), such as body condition, feeding and physiological characters, and photo factory. Broiler breeders are suggested to have shorter lighting length (14 or 15 h) than laying hens (breeders) (16 or 17 h). The advanced sexual maturity is meaningful for poultry industry. With the development of semen dilution and preservation, and alternate use of male breeders, more and more studies are focusing on the effects of light on the reproduction of male breeders. Housing the male breeder underling the same lighting length as females after sexual maturity may reduce semen quality. It is therefore necessary to provide different lighting schedule management for male and female if condition permits. Different from the normal 24-h lighting schedule, ahemeral lighting schedule can increase egg weight, but may lessen production. It is not widely used in practice due to European standards for animal welfare regulations and its inconsistency with the regular schedule of the employee. The study of ahemeral lighting schedule is, however, still important for understanding of the biorhythm of poultry.

chicken; lighting schedule; reproduction; regulatory mechanism

2018-04-04；

2018-07-15

“十三五”國家重點(diǎn)研發(fā)計(jì)劃（2016YFD0500502）、現(xiàn)代農(nóng)業(yè)產(chǎn)業(yè)技術(shù)體系建設(shè)專項(xiàng)資金（CARS-40）、中國農(nóng)業(yè)科學(xué)院科技創(chuàng)新工程（ASTIP-IAS04）

石雷，E-mail：shilei2017@foxmail.com。

陳繼蘭，Tel：010-62816005；E-mail：chen.jilan@163.com