不同水平亚硒酸钠对公鸡睾丸组织中Cdc25A基因表达的影响

通过在公鸡日粮中添加不同水平亚硒酸钠,研究硒对公鸡睾丸组织中细胞周期基因Cdc25A表达的影响,进而为硒调控精子发生周期和生精细胞凋亡的机理提供参考依据。选取80只体重接近、健康无疾病的海兰白成年公鸡,随机分成4组,每组20只,分别在日粮中添加0、0.5、1.0和2.0 mg/kg的亚硒酸钠,试验结束时,采集睾丸备用。采用qRT-PCR 检测硒对公鸡睾丸组织中 Cdc25A 基因的表达差异。结果表明,0.5 mg/kg组Cdc25A表达量显著高于其他处理组,且各组之间差异显著（P<0.05）。由此可见,日粮中硒的最适添加量为0.5 mg/kg,此时,Cdc25A mRNA表达量最高,高硒（超过0.5 mg/kg）则会抑制该基因的表达。     

不同水平亚硒酸钠对公鸡睾丸组织结构及精原干细胞增殖的影响

通过在公鸡日粮中添加不同水平亚硒酸钠,研究硒对公鸡睾丸组织结构及精原干细胞增殖的影响,以期为禽类繁殖性能的研究提供实验依据。选取80只体重接近、健康无疾病的海兰白成年公鸡,随机分成4组,每组20只,分别在日粮中添加0,0．5,1和2mg／kg的亚硒酸钠。通过免疫荧光观察精原干细胞数量。结果显示：日粮中添加适量的硒对睾丸的组织结构及精原干细胞的增殖有显著影响（P〈0．05）,其中0．5mg／kg组显著高于对照组、1mg／kg组和2mg／kg组。结论：适量的硒可以促进鸡睾丸的发育及精原干细胞的增殖,过量的硒对精原干细胞的增殖有一定的抑制作用。     

不同水平母源硒对黎城大青羊后代公羔睾丸发育的影响

试验通过在妊娠期和哺乳期的母羊日粮中添加不同水平酵母硒,研究不同水平母源硒对后代公羔睾丸发育的影响。结果表明:对照组羔羊的睾丸重量、长度和周径均为最低,而0.5 mg/kg组羔羊最高,随后随着日粮硒含量的增加,睾丸重量、长度和周径逐渐降低。H-E染色的结果表明,0.5mg/kg组睾丸的曲精细管管壁最厚,生精细胞数量最多,而2.0 mg/kg与4.0 mg/kg组羔羊睾丸的曲精细管管壁较薄,生精细胞数量相对较少,而且生精细胞之间有较大空隙。试验说明母体中的硒元素可以通过胎盘与乳汁转移给后代,影响后代公羔的睾丸发育。适宜的母源硒可以促进后代公羔的睾丸发育,而较高的硒添加量会对后代睾丸的发育造成不良影响。     

硒对公鸡睾丸发育中毒形态学分析

150只海兰白公鸡雏分为5组,分别饲喂不同硒含量的日粮,I-V组日粮硒含量为1mg/kg、5mg/kg、10mg/kg、15mg/kg、20/mg/kg,在21周龄屠宰,观察睾丸组织结构。结果表明,I组发育最好,生精上皮细胞层数多、管壁厚,管径大,精子簇密集;II组到V组随硒浓度的增加中毒症状明显,生精细胞散乱,生精上皮脱落,精细管溶解。实验结果表明,公鸡日粮中含硒量以不超过1mg/kg为宜。     

微量元素硒对妊娠前期绒山羊母羊生殖激素分泌的影响

选择年龄、体重相近的健康成年经同期发情处理后发情的辽宁绒山羊母羊50只,随机分为5组,其中基础日粮组为对照组,在基础日粮中分别添加0.5 mg/kgDM和1.0 mg/kg DM的亚硒酸钠或蛋氨酸硒作为4个试验组。结果表明:妊娠30d,日粮中分别添加0.5mg/kgDM蛋氨酸硒、1.0mg/kg DM的亚硒酸钠和蛋氨酸硒显著提高了血清FSH含量;妊娠前期日粮添加硒显著提高了血清P4和E2含量,有利于妊娠。从总体效果看,蛋氨酸硒组优于亚硒酸钠组。     

蛋鸡日粮中添加富硒酵母对鸡蛋中硒含量及分布的影响

试验选用产蛋率约为80%的罗曼褐蛋鸡35只,随机分为7组,进行为期30 d的饲养试验。A组为对照组,饲以基础日粮,其余6组为试验组,B、C、D组在基础日粮中分别添加0.2 mg/kg、0.5 mg/kg、1.0 mg/kg的亚硒酸钠;E、F、G组在基础日粮中分别添加0.2 mg/kg、0.5 mg/kg、1.0 mg/kg的富硒酵母,研究其对蛋鸡生产性能和鸡蛋中硒富集的影响。结果显示:日粮中添加硒对蛋鸡生产性能无显著影响,能极显著提高鸡蛋中硒含量,并且硒主要存在蛋黄中。添加富硒酵母组硒含量较亚硒酸钠组提高更为显著。     

不同硒水平对山羊生长性能和血液理化指标的影响

研究在基础日粮中添加不同水平亚硒酸钠对山羊生长发育、血液理化指标及抗氧化的影响。结果表明:在基础日粮中分别添加0.1、0.3mg/kg和0.5mg/kg亚硒酸钠组与基础日粮组相比,羔羊的平均日增重显著增加(P<0.05),以0.3mg/kg亚硒酸钠组增加幅度最大,增加了42.20%(P<0.05);饲料转化率分别提高了18.51%(P>0.05)、40.74%(P<0.05)和29.63%(P<0.05);0.3mg/kg亚硒酸钠组血液中WBC、RBC和血清中TP、ALB、GLO含量显著提高(P<0.05),血清尿素氮的水平显著降低(P<0.05),血清SOD和GSH-Px活性显著升高(P<0.01),血清MDA含量显著降低(P<0.01)。因此,添加亚硒酸钠促进蛋白质合成,改善机体抗氧化功能,促进羔羊生长发育,且以在基础日粮中添加0.3mg/kg最佳。     

大豆黄酮对急性热应激条件下公鸡睾丸发育、精液品质和血清甲状腺激素水平的影响

选取18只32周龄岭南黄公鸡,随机分为3组,每组6只。对照组饲喂基础日粮,试验Ⅰ与Ⅱ组分别在基础日粮中添加大豆黄酮3mg/kg和6mg/kg。试验期14d。在试验的第10天对公鸡施行急性热应激(39℃,2h;40℃,2h)处理,分别于热应激前1d,热应激后4h、2d采集血样测定甲状腺激素(T3、T4)水平。试验结束时,宰杀公鸡、称睾丸重量并观察其组织学结构。结果表明:日粮中添加3mg/kg的大豆黄酮能显著(P<0.05)增加睾丸曲细精管直径。大豆黄酮对急性热应激公鸡的精子活率、精液密度、各级生精细胞含量、睾丸增重、睾丸重/体重等无显著影响。日粮中添喂3mg/kg和6mg/kg的大豆黄酮可降低急性热应激后公鸡T3、T4水平,但无显著差异。     

纳米硒对肉鸡组织硒含量和谷胱甘肽过氧化物酶活性的影响

本试验采用2×6因子完全随机设计,研究了纳米硒和亚硒酸钠2种硒源对肉鸡组织硒含量和谷胱甘肽过氧化物酶(GSH-Px)活性的影响。岭南黄公母混合雏780羽按饲养试验要求分为13组,每组4个重复,每个重复15羽。将纳米硒和亚硒酸钠2种硒源分别以0.1、0.2、0.3、0.4、0.5、1.0mg/kg6个硒水平添加到基础日粮中,配制成12种试验日粮,基础日粮作对照。结果显示:(1)亚硒酸钠添加浓度在0.2～0.4mg/kg硒添加水平范围内肉鸡生长性能和GSH-Px活性处于高峰平台,1.0mg/kg硒添加水平肉鸡生长性能和GSH-Px活性显著低于0.2～0.4mg/kg硒添加水平。纳米硒添加浓度在1.0mg/kg肉鸡生长性能和GSH-Px活性仍然保持在高峰平台。(2)硒源添加浓度在0.1～0.3mg/kg时,亚硒酸钠和纳米硒对肉鸡生长性能的影响无显著差异(P>0.05);硒源添加浓度在0.4～1.0mg/kg时,纳米硒组肉鸡生长性能显著高于亚硒酸钠组(P<0.05)。(3)硒源添加浓度在0.1～0.4mg/kg时,两种硒源对GSH-Px活性的影响无显著差异(P>0.05);在0.5和1.0mg/kg硒添加水平上,纳米硒组GSH-Px活性显著高于亚硒酸钠组(P<0.05)。(4)不加硒的空白组全血和组织硒含量显著低于硒添加组。在同一硒添加水平上,纳米硒组和亚硒酸钠组肉鸡全血硒浓度差异不显著,但是,组织硒含量却受硒源的影响。硒源添加     

硒对公鸡睾丸前期发育的影响

300只海蓝褐公鸡雏分为6组，对照组(CK)伺喂基础日粮，基础日粮含硒量为0．028—0．033mg／kg，I—V组分别补硒1、5、10、15、20mg／kg，在12周龄屠宰，观察发育前期睾丸组织结构。结果表明，CK组缺硒睾丸发育不良，I组发育最好，Ⅱ到V组随硒浓度的增加中毒症状明显，曲精细管肿胀、精细管溶解、生精上皮脱落；经显微结构观察，初步认定公鸡日粮中含硒量以不超过1mg／kg为宜。     

不同水平的亚硒酸钠对鸡心肌组织硒沉积及组织结构的影响

通过在公鸡日粮中添加不同水平的亚硒酸钠,研究硒在公鸡心肌组织中的沉积量和对其组织结构功能的影响,以期为亚硒酸钠在禽类生产中的应用提供参考依据。试验选取80只体重接近、健康无疾病的海兰白成年公鸡,随机分成4组,每组20只,分别在日粮中添加0、0.3、0.6和1.0 mg/kg的亚硒酸钠。试验结束时,采集心组织样本,测定硒含量,并通过HE染色观察组织细胞结构。结果表明,公鸡心肌组织中硒含量随日粮硒含量的增加而升高。由此得出,公鸡心肌组织的硒含量随着日粮硒水平的增加而逐渐升高,高硒日粮对心肌组织的结构有一定影响,但由于硒在心肌组织中的沉积能力与其他组织相比较差,因此影响并不明显。     

鱼油与硒对饲喂亚麻籽日粮绵羊体组织脂肪酸组成及抗氧化的影响

研究0.33%鱼油与2mg/kgDM的有机硒对饲喂亚麻籽日粮的绵羊体组织脂肪酸组成及抗氧化功能的影响。初步探讨在绵羊日粮中添加亚麻籽提高体组织CLA含量的同时,再添加鱼油和硒是否能进一步提高CLA含量。选用体重相近,健康的杂交一代公羔羊16只,随机分为4组。4组日粮为对照组LD组(基础日粮+10%亚麻籽),LF组(基础日粮+0.33%鱼油+9.17%亚麻籽,其中0.33%鱼油+9.17%亚麻籽所含脂肪与10%亚麻籽脂肪含量相等),LDSe组(基础日粮+10%亚麻籽+2mg Se/kgDM);LFSe组(基础日粮+0.33%鱼油+9.17%亚麻籽+2mgSe/kg DM),硒以有机硒的形式添加。结果表明:硒的添加对绵羊血浆抗氧化功能无显著影响(P<0.05),可能是受基础日粮硒浓度的影响;亚麻籽日粮中添加0.33%鱼油提高了绵羊体组织cis-9,trans-11-CLA和trans-11-C18:1含量。亚麻籽日粮中添加2mg Se/kg DM的有机硒对绵羊体组织脂肪酸组成没有显著影响。鱼油与有机硒的添加对绵羊不同组织△9-脱氢酶活性各组间影响差异不显著。由此表明,日粮中联合添加亚麻籽+鱼油以提高组织CLA含量的效果优于单独添加亚麻籽。     

日粮铬对热应激种公鸡肾脏组织结构及血清抗氧化功能的影响

选用72只35周龄罗曼褐种公鸡,随机分为6组,每组12只,对照组饲喂基础日粮,分别在基础日粮中添加0.2、0.4、0.6、0.8、1.0mg/kg铬量的酵母铬,作为试验Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组,在热应激条件下（日：最高温度37.5℃,最低温度28.0℃,平均温度31.7℃）饲养45d。结果显示,在热应激条件下,给种公鸡日粮中添加一定量的酵母铬不仅能有效降低热应激对种公鸡肾脏组织的损伤,而且可显著提高血清中GSH-Px、SOD和CAT活性,降低血清中MDA含量（P〈0.05或P〈0.01）。结果表明,夏季高温环境下,在种公鸡日粮中添加0.8～1.0mg/kg铬量的酵母铬可通过增强机体的抗氧化功能,抑制机体内自由基和脂质过氧化物的产生,保护机体组织细胞膜的完整,维持机体正常生理功能。     

日粮铬水平对热应激种公鸡睾丸组织结构及血浆生殖激素的影响

选择72只35周龄罗曼褐种公鸡,随机分为6组,每组12只,对照组饲喂基础日粮,分别在基础日粮中添加0．2、0．4、0．6、0．8、1．0mg／kg铬量的酵母铬,作为试验Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组,来探讨日粮铬水平对热应激种公鸡睾丸组织结构及血浆生殖激素的影响。结果表明,在热应激条件下,给种公鸡日粮中添加0．8～1．0mg／kg铬量的酵母铬可有效缓解热应激对种公鸡睾丸生精机能的抑制作用,提高种公鸡血浆睾酮（T）、促黄体素（LH）和促卵泡素（FSH）的含量。     

The role of selenium in cadmium toxicity: interactions with essential and toxic elements

1. The study was part of a project designed to investigate if organic selenium (Se) can ameliorate the toxic effects of cadmium (Cd). The main objective of the present study was to investigate, in the chicken, the interactions between Se, Cd and the following elements: Sb, Ca, Cr, Co, Cu, Fe, Pb, Mg, Mn, Mo, Ni, V and Zn.

2. A total of 300 1-d-old chickens (broilers) were randomly distributed among 4 dietary treatments with 5 replicate pens per treatment. In T1, chickens were fed on a diet with 0·3?mg/kg added Se, without added Cd. In T2, chickens were fed on a diet with 0·3?mg/kg Se and 10?mg/kg Cd. In T3, chickens were fed on a diet with 0·3?mg/kg Se and 100?mg/kg of Cd added and in T4 treatment, chickens were fed on a diet with 3?mg/kg Se and 100?mg/kg Cd added. Se was added as Se-yeast. Cd was added as cadmium chloride (CdCl₂). On d 28 and 42, two chickens per replicate pen were killed for collection of whole blood, liver, kidney and breast muscle samples. Samples were analysed by ICP-MS. The data were analysed using a multivariate linear model.

3. While low Cd concentrations in the diet led only to an increase of Cd concentration in the examined tissues, addition of high concentrations of Cd increased the concentration of Cd, Cu, Sb and V and decreased that of Se, Mn and Fe. Addition of high Se concentrations did not significantly reduce Cd concentration.

4. Prior to model application, correlations of 78 elements were noted, while after model application 39 correlations were noted. Most notably, Cd was correlated with Ca, Co, Cu and Mg, while Se was correlated with Mn.

5. The present study revealed several correlations between essential, probably essential and toxic elements illustrating the importance of the balance between pro-oxidants and antioxidants.     

饲粮硒对种公鸡睾丸中硒含量和硒蛋白酶基因mRNA表达的影响

本试验旨在研究饲粮硒对海兰褐种公鸡睾丸中硒含量和硒蛋白酶基因mRNA表达的影响.选取224只48周龄海兰褐种公鸡,随机分为7个处理,每个处理4个重复,每个重复8只.将亚硒酸钠(SS)和酵母硒(SY)2种硒源分别以3个硒水平(0.2、0.5和0.8 mg/kg)添加到海兰褐种公鸡基础饲粮中,对照组饲喂基础饲粮,进行为期3...     

Determination of the selenium requirement in kittens

The purpose of this study was to determine the selenium (Se) requirement in kittens. Thirty-six specific-pathogen-free kittens (9.8 weeks old) were utilized in a randomized complete block design to determine the Se requirement in cats with gender and weight used as blocking criteria. Kittens were fed a low Se (0.02 mg/kg Se) torula yeast-based diet for 5 weeks (pre-test) after which an amino acid-based diet (0.027 mg Se/kg diet) was fed for 8 weeks (experimental period). Six levels of Se (0, 0.05, 0.075, 0.10, 0.20 and 0.30 mg Se/kg diet) as Na2SeO3 were added to the diet and were used to construct a response curve. Response variables included Se concentrations and Se-dependent glutathione peroxidase activities (GSHpx) in plasma and red blood cells (RBC) as well as plasma total T3 (TT3) and total T4 (TT4). No significant changes in food intake, weight gain or clinical signs of Se deficiency were noted. Estimates of the kitten's Se requirement (i.e. breakpoints) were determined for RBC and plasma GSHpx (0.12 and 0.15 mg Se/kg diet, respectively), but no definitive breakpoint was determined for plasma Se. Plasma TT3 increased linearly, whereas plasma TT4 and the ratio of TT4 : TT3 decreased in a quadratic fashion to dietary Se concentration. The requirement estimate determined in this study (0.15 mg Se/kg) for kittens is in close agreement with other species. As pet foods for cats contain a high proportion of animal protein with a Se bioavailability of 30%, it is recommended that commercial diets for cats contain 0.5 mg Se/kg DM.     

Comparison of cupric and sulfate ion effects on chronic selenosis in rats

The ameliorating effects of Cu++ and SO4--ions on concurrent selenite toxicity were compared in two factorial experiments using 60 weanling rats each. In the first experiment, 0, 500 and 1,000 mg Cu (as CuCl2)/kg diet were fed in conjunction with 0, 5, 10 and 20 mg Se (as Na2SeO3)/kg diet. In the second experiment, the treatments were 0, 500 and 1,000 mg SO4 (as Na2SO4)/kg fed in conjunction with 0, 5, 10 and 20 mg Se/kg diet. A paired-feeding experiment using 10, 15 and 20 mg Se/kg diet was also conducted with 28 rats to compare the influence of inanition in control and selenite-fed rats. Cupric++ ion, but not SO4--ion, prevented mortality among selenite-intoxicated rats. There were significant Cu X Se interaction effects on feed intake, daily gain, packed cell volume (PCV), serum Cu and Fe, sperm counts, and weights of liver, kidney and testis. There were main effects of Cu and Se on serum Se and liver Cu. In Exp. 2 there were significant SO4 X Se interaction effects on feed intake, daily gain, serum Cu and testis weight. There were main effects of Se on PCV, sperm count, serum testosterone, liver Se, liver Cu and the absolute weights of liver and kidney. The only main effect of SO4 was that of increased liver Cu concentrations. Among the pair-fed rats, the selenite-fed rats, with one exception, died before their paired rats.(ABSTRACT TRUNCATED AT 250 WORDS)