维生素、矿物质与能量蛋白质水平对浙东白鹅母鹅繁殖性能、血液生殖激素浓度及生殖轴相关基因mRNA相对表达量的影响

本试验通过在饲粮中添加维生素与矿物质、调整饲粮能量蛋白质水平,旨在研究其对浙东白鹅母鹅繁殖性能、血液生殖激素浓度和生殖轴相关基因mRNA相对表达量的影响.选择138只月龄相近的浙东白鹅种母鹅,按体重相近原则分为3组,分别饲喂不同的饲粮,试验期150 d,测定繁殖性能(平均产蛋数、平均蛋重、受精率和孵化率)、血液生殖激素[卵泡刺激素(FSH)、促黄体生成素(LH)、孕酮(P4)、雌二醇(E2)、催乳素(PRL)]浓度和生殖轴相关基因[促性腺激素释放激素(GnRH)、卵泡刺激素-β(FSHβ)、雌激素受体1(ESR1)、雌激素受体2(ESR2)、卵泡刺激素受体(FSHR)、催乳素(PRL)、催乳素受体(PRLR)] mRNA相对表达量的变化.结果表明:1)添加维生素与矿物质可显著提高浙东白鹅母鹅第1产蛋周期平均蛋重和受精率(P＜0.05);提高第2产蛋周期内血液FSH和P4的浓度,降低LH浓度,改变E2、P4和PRL浓度波动(P＜0.05);下调下丘脑PRLR、垂体PRL和卵巢PRLR基因的mRNA相对表达量(P＜0.05),上调卵巢ESR2基因的mRNA相对表达量(P＜0.05).2)调整饲粮能量蛋白质水平可显著提高浙东白鹅母鹅第2产蛋周期平均蛋重(P＜0.05);提高浙东白鹅第2产蛋周期内血液LH浓度,降低FSH浓度,改变E2和P4浓度波动(P＜0.05);上调下丘脑GnRH、垂体PRL和PRLR基因的mRNA相对表达量(P＜0.05),下调卵巢FSHR基因的mRNA相对表达量(P＜0.05).由此得出,添加维生素与矿物质、调整饲粮能量蛋白质水平可通过影响产蛋周期内部分血液生殖激素浓度和波动,局部调节生殖轴相关基因的mRNA相对表达量,改善浙东白鹅母鹅的繁殖性能.     

皖西白鹅催乳素受体基因表达特点的研究

采用荧光定量PCR法,研究了皖西白鹅催乳素受体基因(prolactin receptor,PRLR)在产蛋不同时期及生殖轴不同组织mRNA的表达特点。结果表明,在垂体、下丘脑和卵巢组织中,皖西白鹅产蛋前期PRLR表达水平较低,至产蛋期降至最低,抱窝期上升至极高水平,休产期再次下降至较低水平,且各组织均表现出相似的规律,但卵巢中的表达量相对较高;就巢期间,在就巢前、中、后期,PRLR mRNA表达量在各组织呈现不同的变化规律,垂体组织中表达量呈"V"形变化,在中期前下丘脑中PRLR mRNA维持稳定,到后期有所下降,卵巢中表达量呈梯形下降。PRLR mRNA表达量在不同周期及不同组织中的变化规律反应了PRLR对皖西白鹅就巢的影响,PRLR对鹅就巢的调控可能在转录时期已经开始。     

鹅不同繁殖时期GnRH和GnIH基因表达和激素浓度变化分析

旨在研究GnRH和GnIH基因和激素在鹅繁殖过程中的重要作用,本研究以产蛋性能差异显著的四川白鹅和溆浦鹅为试验材料,利用Real-time RCR方法检测产蛋前期、产蛋期和休产期两种鹅的下丘脑、垂体和卵巢组织中GnRH和GnIH mRNA的表达量;利用放射性免疫和酶联免疫吸附测定法测定血清中的GnRH和GnIH激素变化情况。结果表明:GnRH和GnIH基因在四川白鹅和溆浦鹅的下丘脑、垂体和卵巢组织中均有表达;产蛋前期和产蛋高峰期的下丘脑和卵巢组织中,四川白鹅的GnRH mRNA表达量显著(P0.05)或极显著(P0.01)高于溆浦鹅,在产蛋高峰期和休产期四川白鹅GnRH激素浓度也极显著(P0.01)或显著高于(P0.05)溆浦鹅,在高峰期和休产期四川白鹅GnRH血清浓度分别为51.13和51.10pg·mL-1,溆浦鹅分别为49.52和49.94pg·mL-1;GnIH在两种鹅的变化比较一致,仅在产蛋高峰期,四川白鹅下丘脑组织中GnIH mRNA表达水平极显著低于(P0.01)溆浦鹅,而两种鹅之间的GnIH激素在各个时期均无显著差异。这提示随着繁殖阶段的改变,在调控两种鹅产蛋性能的作用过程中GnRH可能较GnIH发挥着更为重要的作用,为进一步研究鹅繁殖分子机制奠定基础。     

浙东白鹅催乳素受体基因的克隆及其表达特点的研究

本研究克隆了浙东白鹅催乳素受体基因（PRLR）的部分序列,并应用荧光定量PCR技术研究了浙东白鹅在产蛋期、就巢期和恢复期时PRLR基因在下丘脑、垂体和卵巢中的表达特点,结果表明,浙东白鹅PRLR基因的表达量在产蛋期、就巢期和恢复期差异显著（P〈0.05）,就巢期表达量最高,产蛋期次之,恢复期表达量最低。对不同组织PRLR的表达量分析,垂体最多,其次是下丘脑,卵巢中的表达量最低,垂体与卵巢中的表达量、卵巢与下丘脑的表达量均有极显著的差异（P〈0.01）,垂体与下丘脑中的表达量差异不显著（P〉0.05）。     

黑羽番鸭PRL、PRLR基因序列分析及表达规律研究

催乳素(Prolactin,PRL)由动物垂体前叶分泌,与其受体(Prolactin receptor,PRLR)相结合才能作用于靶细胞。为了解PRL与PRLR基因在黑羽番鸭不同繁殖阶段各组织内的时空表达规律,利用RACE扩增方法获得了PRL与PRLR基因的CDS区序列,同时应用荧光定量与免疫组化相结合的方法,对产蛋前期、产蛋期、就巢期的黑羽番鸭垂体、卵巢、子宫中PRL与PRLR基因的表达量进行了比较分析。结果显示:PRL与PRLR基因序列在多种禽类中高度同源;PRL基因在垂体、卵巢、子宫中m RNA的表达具有明显的空间特异性,PRL基因在垂体中表达量最高,极显著高于卵巢和子宫中的表达量(P0.01),这种趋势贯穿产蛋前期、产蛋期和就巢期。PRLR基因在不同时期各组织内m RNA的表达具有明显的时空特异性。PRLR基因的表达量在垂体、卵巢中的表达量普遍较低,子宫中的表达量最高。PRLR基因在不同时期垂体和卵巢中的表达量没有明显的差异(P0.05),而子宫中的表达量在就巢期显著高于产蛋前期与产蛋期(P0.05)。     

日粮粗蛋白质水平对伊犁鹅产蛋规律、繁殖激素分泌及相关基因mRNA表达的影响

为探讨日粮粗蛋白质水平对伊犁鹅的产蛋规律、繁殖激素分泌及生殖轴相关基因mRNA表达量的影响,本研究随机选取200只3岁伊犁鹅(年龄、饲养管理水平一致及体重相近),随机分为4个组,每组10个重复。对照组及公鹅饲喂鹅场自配料(粗蛋白质水平11.20%),试验组母鹅分别饲喂粗蛋白质水平为13.86%、15.20%和16.48%的日粮,其余营养指标基本一致。预试期1周,正试期9周。结果表明:①试验期内伊犁鹅的产蛋率呈波动变化,对照组伊犁鹅的产蛋率在第1～2周逐渐上升,第4～5周出现小幅度增长,其余阶段表现为下滑趋势;各试验组伊犁鹅的产蛋率在第1～2、4～5周出现较大幅度增长,且在第5周时达到产蛋高峰,此后逐渐下滑。15.20%粗蛋白质组伊犁鹅就巢率显著低于11.20%、13.86%粗蛋白质组。②与对照组相比,13.86%粗蛋白质组血清促性腺激素释放激素(GnRH)浓度极显著升高(P0.01),且血清雌二醇(E_2)、促黄体素(LH)浓度均显著升高(P0.05);15.20%、16.48%粗蛋白质组血清GnRH、E_2及LH浓度均极显著升高(P0.01),且血清促卵泡素(FSH)浓度显著升高(P0.05)。各试验组血清催乳素(PRL)浓度均显著降低(P0.05)。③与对照组相比,15.20%粗蛋白质组下丘脑GnRH、LHR基因表达量显著上调(P0.05),PRL、PRLR基因表达量显著下调(P0.05);垂体中LH基因表达量显著上调(P0.05);卵巢中LH与ESR2基因表达量显著或极显著上调(P0.05,P0.01)。综上所述,基于日粮粗蛋白质水平对伊犁鹅的产蛋率、就巢率、血清生殖激素浓度及生殖轴相关基因mRNA相对表达量影响的综合评估,建议产蛋期伊犁鹅日粮粗蛋白质水平为15.20%。     

鹅催乳素基因外显子2变异及其遗传效应

动物垂体前叶分泌的催乳素(Prolactin,PRL)具有广泛的生理效应,在家禽中与就巢、产蛋等繁殖性能有重要关联.本试验以皖西白鹅和莱茵鹅作为研究素材,运用PCR-SSCP法检测鹅PRL基因外显子2的单核苷酸变异并分析了变异的遗传效应.检测发现在皖西白鹅中存在C196T碱基突变,在莱茵鹅群体发现C170T碱基突变.关联分析结果表明,2个品种中的PRL基因外显子2突变均对鹅的开产蛋质量有显著(P<0.05)影响.     

产蛋前期和产蛋期鹅HPG轴褪黑素受体mRNA表达规律的研究

为阐明不同繁殖阶段鹅HPG轴褪黑素受体mRNA表达的变化规律,应用实时荧光定量PCR技术检测产蛋前期和产蛋期四川白鹅下丘脑、垂体、卵巢组织中3种褪黑素受体亚型(Mel-1a、Mel-1b和Mel-1c)mRNA相对表达量。结果表明:产蛋前期鹅下丘脑Mel-1a、Mel-1b和Mel-1c的相对表达量分别是产蛋期的5.25倍(P<0.01)、0.43倍(P<0.01)和1.20倍(P<0.01);产蛋前期鹅垂体Mel-1a、Mel-1b和Mel-1c的相对表达量分别是产蛋期的3.01倍(P<0.01)、7.51倍(P<0.01)、7.25倍(P<0.01);产蛋前期鹅卵巢组织中Mel-1a、Mel-1b和Mel-1c的相对表达量分别是产蛋期的1.55倍(P<0.01)、0.55倍(P<0.01)、2.86倍(P<0.01)。以上结果提示,褪黑素可通过其特异性受体的介导在HPG轴的各级水平发挥其调节作用,并且下丘脑褪黑素主要通过Mel-1a介导、垂体褪黑素主要通过Mel-1b和Mel-1c,卵巢褪黑素主要通过Mel-1a和Mel-1c介导来发挥其调控作用。     

太湖鹅繁殖性能与肉质特性研究

为挖掘和利用太湖鹅遗传资源,利用太湖保种场核心群对太湖鹅的繁殖性能进行测定,在相同饲养管理条件下比较太湖鹅与四川白鹅、皖西白鹅、豁眼鹅、扬州鹅的肉质特性差异。结果表明:太湖鹅3%开产日龄188d,66周入舍母鹅产蛋76.3个,52周龄蛋重142.7g,种蛋受精率91.2%,受精蛋孵化率90.1%;太湖鹅胸肌肉水分含量与四川白鹅差异显著(P<0.05),与其它品种差异不显著,太湖鹅胸肌剪切力、肉色、系水力、pH值、粗蛋白和粗脂肪含量与其它品种间差异均不显著;太湖鹅肌纤维密度显著大于四川白鹅、豁眼鹅和扬州鹅(P<0.05),但显著小于皖西白鹅(P<0.05);太湖鹅肌纤维直径显著小于其它品种(P<0.05)。研究表明,太湖鹅经过进一步选育可以作为优质肉鹅配套系的理想母本。     

时钟基因在扬州鹅内分泌组织中的节律性表达

鹅产蛋行为是典型的节律行为,为了揭示时钟基因在扬州鹅不同内分泌组织中的节律性表达规律,选取在连产周期内且产蛋时间基本一致的扬州鹅24只,在48 h内每隔6 h采集3只鹅的下丘脑、垂体、卵巢组织样品,并采用RT-qPCR分别检测Clock、Bmal1、Bmal2、Cry1、Cry2、Per2基因在不同时间点的表达变化。结果显示:所检测的6个时钟基因在3个组织中均有所表达,且在不同的时间点表达量有所差异。其中Clock基因在3个组织中的表达均呈现出节律性,Bmal1基因在垂体和卵巢中表现出节律性,Bmal2基因在卵巢中表现出节律性,Per2基因在下丘脑、卵巢组织中与Clock基因表达趋势相反,表现出负反馈调节作用。表明Clock基因很有可能介导Per2参与鹅产蛋行为节律调控。     

The phytoestrogen daidzein may affect reproductive performance of Zhedong White geese by regulating gene mRNA levels in the HPG axis

1. The effect of daidzein, a naturally occurring phytoestrogen, on the reproductive performance of 120 female Zhedong White geese was determined. The geese were divided into 4 groups which were fed on diets containing 0 (Control), 10 (Da1), 20 (Da2) and 30 (Da3) mg daidzein per kg diet. Egg production and weight, fertility and hatchability rates, concentrations of estradiol (E₂), triiodothyronine (T₃), progesterone (P₄), thyroxine (T₄) and growth hormone (GH) in serum, and mRNA levels of gonadotropin releasing hormone (GnRH), β-follicle stimulating hormone (FSHβ), follicle stimulating hormone receptor (FSHR), oestrogen receptor1 (ESR1), oestrogen receptor2 (ESR2), prolactin (PRL), prolactin receptor (PRLR), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in the hypothalamus-pituitary-gonadal axis (HPGA) were measured.

2. Daidzein increased egg weight and fertility but had no detectable effect on egg production and hatchability.

3. Daidzein affected serum P₄ and GH concentrations and T₄ rhythm, up-regulated GnRH mRNA and PRLR mRNA levels in the hypothalamus, down-regulated PRLR mRNA in the hypothalamus, PRL mRNA in the pituitary, and ESR2 mRNA levels in the ovary, respectively. The mRNA rhythms of PRLR in the hypothalamus, PRL, PRLR and FSHβ in the pituitary, FSHR, ESR1 and ESR2 in the ovary were significantly changed in the Da2 group.

4. It is suggested that an appropriate dose of daidzein might improve reproductive performance by affecting serum hormone concentrations and rhythms and regulating gene mRNA levels in the HPGA of female Zhedong White geese.     

Characterization of ovarian morphology and reproductive hormones in Zhedong white geese (Anser cygnoides domesticus) during the reproductive cycle

Zhedong white goose (Anser cygnoides domesticus) is a native Chinese breed with strong broodiness and low egg production, which is related to the physiology of reproduction. However, thus far, the physiology of goose reproduction has not been well elucidated. In the present study, the ovarian morphology and reproductive hormones of Zhedong white geese were investigated during the reproductive cycle (the laying and brooding periods). The results showed that the surface of the ovary was atrophied and follicular atresia appeared to some extent in the brooding period compared with the laying period. The concentrations of follicle-stimulating hormone, progesterone and luteinizing hormone were significantly higher than those in the brooding period (p < 0.05). In contrast, the concentrations of prolactin (PRL) and anti-Müllerian hormone (AMH) in the laying period were significantly lower than those in the brooding period (p < 0.05). In addition, the mRNA expression levels of PRL, AMH, dopamine-β-hydroxylase (DβH) and cytochrome P450 side-chain cleavage enzyme (P450scc) were detected in the hypothalamus, pituitary and ovaries by using real-time polymerase chain reaction. The results showed that AMH mRNA was expressed specifically in ovary tissue. The expression levels of DβH and PRL in the brooding period was significantly higher than those in the laying period in the three tissues, especially in the early and middle stages of the brooding period. Moreover, AMH mRNA expression in the ovaries presented the same trend. In addition, P450scc mRNA was highly expressed in both the ovary and pituitary in the laying period. These results revealed the remarkable features of ovarian morphology and characterized the hormonal pattern and expression profile during the reproductive cycle, all of which contribute to understanding the differences in reproductive physiology between the laying and brooding periods in Zhedong white geese.     

日粮粗蛋白质水平对伊犁鹅产蛋规律、繁殖激素分泌及相关基因mRNA表达的影响

为探讨日粮粗蛋白质水平对伊犁鹅的产蛋规律、繁殖激素分泌及生殖轴相关基因mRNA表达量的影响,本研究随机选取200只3岁伊犁鹅（年龄、饲养管理水平一致及体重相近）,随机分为4个组,每组10个重复。对照组及公鹅饲喂鹅场自配料（粗蛋白质水平11.20%）,试验组母鹅分别饲喂粗蛋白质水平为13.86%、15.20%和16.48%的日粮,其余营养指标基本一致。预试期1周,正试期9周。结果表明：①试验期内伊犁鹅的产蛋率呈波动变化,对照组伊犁鹅的产蛋率在第1~2周逐渐上升,第4~5周出现小幅度增长,其余阶段表现为下滑趋势;各试验组伊犁鹅的产蛋率在第1~2、4~5周出现较大幅度增长,且在第5周时达到产蛋高峰,此后逐渐下滑。15.20%粗蛋白质组伊犁鹅就巢率显著低于11.20%、13.86%粗蛋白质组。②与对照组相比,13.86%粗蛋白质组血清促性腺激素释放激素（GnRH）浓度极显著升高（P<0.01）,且血清雌二醇（E₂）、促黄体素（LH）浓度均显著升高（P<0.05）;15.20%、16.48%粗蛋白质组血清GnRH、E₂及LH浓度均极显著升高（P<0.01）,且血清促卵泡素（FSH）浓度显著升高（P<0.05）。各试验组血清催乳素（PRL）浓度均显著降低（P<0.05）。③与对照组相比,15.20%粗蛋白质组下丘脑GnRH、LHR基因表达量显著上调（P<0.05）,PRL、PRLR基因表达量显著下调（P<0.05）;垂体中LH基因表达量显著上调（P<0.05）;卵巢中LH与ESR2基因表达量显著或极显著上调（P<0.05,P<0.01）。综上所述,基于日粮粗蛋白质水平对伊犁鹅的产蛋率、就巢率、血清生殖激素浓度及生殖轴相关基因mRNA相对表达量影响的综合评估,建议产蛋期伊犁鹅日粮粗蛋白质水平为15.20%。     

Physiological and hormonal aspects in female domestic pigeons (Columba livia) associated with breeding stage and experience

The present study examined the changes in serum biochemical values, hormone profiles and ovary prolactin receptor (PRLR) gene expression occurring in female domestic pigeons (Columba livia) under different breeding status and experience. The egg‐laying pigeons had lower calcium, total protein, albumin, prolactin levels and higher oestrogen levels than those of incubating birds (p < 0.05). First‐time breeders had higher (p < 0.05) progesterone levels and lower (p < 0.05) prolactin levels than that of experienced ones. The levels of oestrogen and follicle‐stimulating hormone (FSH) increased with age (p < 0.05). The very old birds showed a pronounced increase (p < 0.05) in PRL, FSH and progesterone and a little decrease in oestrogen. Serum prolactin level was not correlated with the ovary PRLR mRNA expression pattern among all the pigeons. Results showed that serum physiological profile of female pigeons was correlated with breeding status, whereas reproductive hormone levels were correlated with advancing breeding experience. It was concluded that female pigeons had a good ability of recovering from nutrient loss after each breeding attempts, and the degradation of reproductive performance might be attributed to changes in the endocrine system.     

Effects of supplemental vitamin E during the laying period on the reproductive performance of Taiwan native chickens

1. One-day-old Taiwan Native Breeder female chicks were fed on maize/soybean growing diets without supplemental vitamin E from hatch to 17 weeks of age. After 17 weeks the birds (n = 300) were randomly assigned to 5 dietary treatments and fed on maize/soybean laying diets supplemented with 0, 40, 80, 120 and 160 mg/kg of vitamin E (dl-alpha-tocopherol acetate), respectively, until 46 weeks of age. The variates measured included: age at first egg, feed consumption (FC), feed efficiency (FE), egg production (EP), egg weight (EW), egg specific gravity (ESG), eggshell strength (ESS), fertility and hatchability. 2. The addition of 120mg/kg of vitamin E lowered the first EW (P<0.05); however, there was no significant difference in the age or body weight (BW) of pullets at first egg or mortality rate to 46 weeks of age among the treatments. FE and egg mass were improved (P<0.05) in pullets fed 80 mg/kg of supplemental vitamin E. A significant increase in EP was observed after peak EP in pullets given 80 mg/kg of supplemental vitamin E. However, this favourable effect decreased as supplemental vitamin E exceeded 80 mg/kg. 3. From 17 to 46 weeks of age, egg quality (ESG and ESS) decreased with age. However, there was no correlation between age and fertility or hatchability during the experimental period, suggesting that egg quality is more age-sensitive than reproductive performance for breeder pullets. 4. Compared with the control, fertility and hatchability of all eggs set for the treatment with 80 mg/kg supplemental vitamin E increased by 7.7 and 13.4%, respectively. There was no difference in the hatchability of fertile eggs. 5. These results suggest that using supplemental vitamin E during the laying period can improve the reproductive performance of breeder pullets. The addition of 80 mg/kg of vitamin E obtained the best performance in EP, egg mass, FE (feed/egg), hatchability and fertility.     

高、低产双黄蛋高邮鸭卵巢组织差异分析

本试验以高邮鸭为研究对象,选择双黄蛋高、低产组高邮鸭各6只,颈动脉放血致死后立即采集下丘脑、垂体、肝脏、输卵管及卵巢组织,将采集的卵巢组织通过组织切片、HE染色观察卵巢形态结构,并对双黄蛋高、低产组高邮鸭卵巢中等级卵泡进行统计对比;进行特异性标记蛋白卵泡刺激素受体（FSHR）免疫组化染色,观察两组高邮鸭卵巢阳性细胞表达情况及卵巢颗粒细胞分布;同时提取下丘脑、垂体、肝脏、输卵管及卵巢组织RNA,采用实时荧光定量PCR技术检测FSHR基因的表达。结果显示,双黄蛋高产和低产组高邮鸭卵巢在组织结构及卵泡发育上存在明显差异,高产组卵巢上的卵泡繁密且发育良好,密布着众多小黄卵泡、大白卵泡及小白卵泡,各级卵泡大小差异明显;而低产组卵巢上的卵泡稀疏且发育较为迟缓,小黄卵泡、大白卵泡及小白卵泡数量较少。实时荧光定量PCR检测结果表明,高产组高邮鸭下丘脑、垂体、肝脏及输卵管中的FSHR基因表达量极显著高于低产组（P<0.01）,而卵巢中FSHR基因表达量在两组中差异不显著（P>0.05）。本试验结果表明,双黄蛋高、低产组高邮鸭的卵巢结构及卵泡发育存在显著差异,卵巢上的微环境可能是影响高邮鸭双黄蛋产蛋性能的影响因素。     

笼养蛋鸭舍环境因子与鸭免疫机能及生产性能的研究

试验检测了春季蛋鸭笼养舍内环境因子分布和蛋鸭生理机能及生产性能变化,为蛋鸭阶梯式笼养模式提出改进建议。结果表明:(1)蛋鸭舍内气载有害菌和粉尘浓度随纵向通风进程持续升高,上层鸭笼大肠杆菌属细菌气溶胶浓度显著低于中层和下层(P<0.05)。平均光照强度自进风口到出风口分布均匀,但上层笼极显著高于下层(P<0.01);(2)上层蛋鸭平均产蛋率(69.37%)显著高于下层蛋鸭(P<0.05);累计死淘率(0.11%)显著低于下层蛋鸭(P<0.05);(3)上层鸭蛋哈氏单位为68.2,极显著高于下层鸭蛋(P<0.01);(4)上层蛋鸭血清过氧化氢酶(CAT)活性、下丘脑GnRH基因表达水平均显著高于下层蛋鸭(P<0.05);下丘脑CRH基因表达水平,脾脏IL-1β、IL-10和TNF-α基因表达水平显著低于下层蛋鸭(P<0.05)。以上结果显示,春季笼养蛋鸭舍内,不同空间位置环境因子分布不均匀,下层蛋鸭长期处于恶劣环境,增加了死亡率,降低了产蛋率和蛋品质。     

饲粮添加维生素E和酵母硒对黄羽肉种鸡产蛋性能、孵化性能及蛋中维生素E和硒沉积量的影响

本试验旨在研究饲粮添加维生素E和酵母硒对黄羽肉种鸡产蛋性能、孵化性能及蛋中维生素E和硒(Se)沉积量的影响。试验采用3×3双因子设计,设3个维生素E添加水平(0、20、40 IU/kg)和3个Se添加水平(0、0.15、0.30 mg/kg)。选用32周龄快大型岭南黄羽肉鸡父母代种母鸡864只,根据产蛋率和体重一致性原则随机分成9个组,分别为VE_0Se_0组、VE_0Se_(0.15)组、VE_0Se_(0.30)组、VE_(20)Se_0组、VE_(20)Se_(0.15)组、VE_(20)Se_(0.30)组、VE_(40)Se_0组、VE_(40)Se_0.15组和VE_(40)Se_0.30组,每组6个重复,每个重复16只鸡。试验期8周。结果表明:1)饲粮中维生素E和Se添加水平对黄羽肉种鸡的体增重、平均日产蛋量、料蛋比、平均蛋重、产蛋率、破蛋率和不合格蛋率均无显著影响(P0.05)。2)饲粮中维生素E和Se添加水平对黄羽肉种鸡的蛋长径、蛋短径、蛋白高度、蛋黄颜色、哈氏单位、蛋黄重、蛋壳重和蛋壳厚度均无显著影响(P0.05)。3)饲粮中维生素E和Se添加水平对黄羽肉种鸡的健雏出壳重、孵化率、弱雏率和受精率均无显著影响(P0.05)。4)饲粮中维生素E添加水平对黄羽肉种鸡血浆MDA含量有显著影响(P0.05),随饲粮中维生素E添加水平的升高血浆MDA含量呈降低趋势,其中维生素E添加水平为40 IU/kg时血浆MDA含量显著低于0 IU/kg时(P0.05);饲粮中维生素E和Se添加水平对血浆MDA含量有显著交互作用(P0.05),其中VE_(40)Se_0组的血浆MDA含量显著低于VE_0Se_(0.15)和VE_0Se_(0.30)组(P0.05)。5)随饲粮中维生素E和Se添加水平的升高,黄羽肉种鸡蛋中维生素E和Se含量显著增加(P0.05);饲粮中维生素E和Se添加水平对蛋中维生素E和Se含量有显著交互作用(P0.05)。结果提示,维生素E可以提高黄羽肉种鸡的抗氧化水平,饲粮中维生素E和Se添加水平可以显著影响蛋中维生素E和Se的含量;建议在无任何应激因素刺激和不使用Se缺乏地区饲料原料的情况下,黄羽肉种鸡玉米-豆粕型饲粮可以不用额外添加维生素E和Se。     

维生素E对免疫抑制产蛋鸡生产性能和蛋品质的调控效应

试验探讨维生素E对免疫抑制蛋鸡生产性能和蛋品质的调控效应,选取健康的尼克褐产蛋鸡270只,随机等分为5组,每组3个重复,每重复18只。第Ⅰ组为对照组,第Ⅱ~Ⅴ组为免疫抑制组,对第Ⅱ~Ⅴ组鸡在试验第5、6、7 d进行腿部肌肉注射80 mg/kgBW环磷酰胺(CTX),第Ⅰ组注射等量生理盐水。Ⅰ、Ⅱ组饲喂基础日粮(维生素E含量44.59 mg/kg),Ⅲ、Ⅳ、Ⅴ组在基础日粮中分别添加50、100、200 mg/kg维生素E。结果显示:①免疫抑制产蛋鸡的产蛋率、平均蛋重和平均日采食量显著降低(P<0.05),破蛋率显著升高(P<0.05)。基础日粮中添加50 mg/kg维生素E显著提高免疫抑制产蛋鸡的产蛋率、平均蛋重和平均日采食量(P<0.05),但仍低于对照组Ⅰ(P<0.05);显著降低料蛋比和破蛋率(P<0.05)。②免疫抑制产蛋鸡的蛋壳厚度、蛋壳强度和哈氏单位显著降低(P<0.05),蛋形指数和蛋黄颜色无显著改变(P>0.05);50 mg/kg维生素E添加量显著提高免疫抑制产蛋鸡的蛋壳厚度、蛋壳强度和哈氏单位(P<0.05),与对照组Ⅰ无显著差异(P>0.05)。因此,免疫抑制显著降低产蛋鸡的生产性能和蛋品质;基础日粮中添加维生素E对免疫抑制蛋鸡的生产性能和蛋品质具有明显的调控效应,且以50 mg/kg添加量效果较好。