蒙古牛和延边牛的染色体研究

做了4头蒙古牛(♂)和12头延边牛(11♂,1(?))的染色体研究。做了两种牛的常规染色、C带和核仁组织者区银染色的核型和蒙古牛的G带核型分析。蒙古牛的Y染色体为亚中着丝点,而延边牛为中着丝点,存在形态上的差别,但他们的大小均位于24—25号常染色体之间。蒙古牛和延边牛的Ag—NORs均定位于2.3.4.11.28号常染色体末端,但发现延边牛的Ag—NORs也定位于21(或22)号染色体末端。根据两种牛的Y染色体和Ag—NORs多态性讨论了它们的起源问题。     

温岭高峰牛的染色体研究

用C带、G带、RBA带、核仁组织者区银染色和常规+RBA带连续染色技术研究了我国南方的9头温岭高峰公牛、2头母牛和1头温岭(♀)利本赞(♂)的杂种公牛的染色体。温岭牛2n=60,公牛xy,母牛xx,x为一大的亚中着丝点杂色体,Y为小的近端着丝点染色体。杂种公牛的Y为小的亚中着丝点染色体。温岭牛的Ag—NORs除定位于2、3、4、11、28号染色体上之外,在21号染色体上也有银染颗粒,但出现频率很低。21号和28号染色体末端Ag—NOR出现频率分别为每细胞0.11个和1.79个。温岭牛中存在2/27罗伯逊易位。     

3个地方鸡种的核型及其似近系数分析

运用外周血淋巴细胞培养法，对我国3个地方鸡种(仙居鸡、北京油鸡、狼山鸡)染色体核型进行了研究，结果显示：仙居鸡、北京油鸡、狼山鸡染色体形态十分相似，No．1、No．2、No．8、Z、W染色体都为m型；No．6染色体都为sm型；No．3、No．5、No．7、No．9染色体都为t型，仅在No．4染色体形态和W染色体的相对长度表现出一定的差异。此外，核型似近系数和进化距离聚类分析表明，7个地方鸡种(另收集了鹿苑鸡、寿光鸡、泰和鸡和旧院黑鸡的资料)可分为3个类群，其结果与起源进化，产地分布大致相同。     

Wistar系大鼠染色体核型及分带研究

采用常规及分带技术,对Wistar系大鼠染色体研究的结果如下:2n=42;1;X号染色体为亚端着丝点染色体;2～10;Y号为端部着丝点染色体;11～13号为亚中部着丝点染色体;14～20号为中部着丝点染色体.染色体G-带与天津Ⅰ系大鼠G-带基本一致.染色体Ag—NORs定位于11,12,13以及X号染色体上,分布范围为1～7个,众数为6个.染色体C-带明显者为4～8,10～12,14～19,X号染色体,C-带不明显者为1～3,9,13,20,Y号染色体.     

藏鸡和茶花鸡染色体G带比较

运用改进的鸡外周血淋巴细胞培养-空气干燥法,分析了藏鸡和茶花鸡染色体G带。G带研究结果表明：2个地方鸡种的染色体G带带纹存在一定差异,主要体现在带纹数目的差异和带纹宽度的差异,藏鸡前10对大型染色体可分为33个区,共149条带,而茶花鸡可分为34个区,共146条带;同时对2个地方鸡种G带带型特征进行详细比较,并绘制了G带模式图。     

固始鸡核型、G带的研究

采用外周血淋巴细胞培养法对固始鸡染色体核型和G带进行了研究。结果表明:固始鸡体细胞染色体数目2n=78,染色体基本臂数为NF=88,No.1、Z和W染色体为中央着丝粒(m)染色体,No.2、No.4、No.7染色体为亚中央着丝粒(sm)染色体,No.3、No.6、No.8、No.9、No.10为端着丝粒(t)染色体。G带研究表明:前10对大染色体(包括Z、W染色体)共可分为34个区,138条深带核和带。     

4个品种鸡Toll样受体4基因第2内含子的多态性分析

本研究采用PCR-SSCP和DNA测序的方法检测了4个品种鸡(仙居鸡、白耳鸡、清远麻鸡和安卡鸡)Toll样受体4(Toll-like receptor 4,TLR4)基因第2内含子的单核苷酸多态性。结果表明,4个品种鸡TLR4基因的第2内含子上均发现了G1894C的突变,共产生了AA、AB和BB 3种基因型,4个品种鸡该位点的多态信息含量(PIC)分别为0.570、0.597、0.583和0.588,均属于高度多态性,且处于Hardy-Weinberg平衡状态(P>0.05);4个品种鸡G1894C多态位点的基因型在感染鸡白痢沙门氏菌阳性组和阴性组间的分布差异均不显著(P>0.05);G1894C多态位点在仙居鸡与白耳鸡2个品种间基因型分布差异极显著(P<0.01)。     

香猪等五品种猪的C—带和银染带的分析和比较

本文分析和比较了香猪、北京黑、长白、长北和社长北杂种的C-带和银染带。指出了家猪有可能存在Lin所没有揭示的异染质。得出了它们的NORs平均值分别为3.96、3.88、2.03、2.95和3.00。NORs联合率平均值为3.00％,但香猪高达7.31％。对香猪的结果分析表明,香猪具有以下细胞学特征:(1)染色体Y长;(2)染色体Y长臂C-带浅染;(3)D组染色体C-带具有极大的多态性;(4)染色体2～4之一的长臂有时出现C-带;(5)染色体NORs联合率高。     

河南斗鸡染色体核型及G带的研究

运用外周血淋巴细胞培养法 空气干燥法制备染色体标本，对河南斗鸡的核型、G带进行了研究。核型研究结果表明：河南斗鸡染色体数目2n=78，1号和Z染色体为中央着丝粒(m)染色体，2、7、W染色体为亚中央着丝粒（sm）染色体，3、6、8、9、10号染色体为端着丝粒（t）染色体，4号染色体为亚端着丝粒（st）染色体。G带研究结果表明：前10对大型染色体可分为25个区，152条深带和浅带。     

部分鸡品种血浆胆固醇含量比较研究

本试验对乌骨鸡、仙居鸡、萧山鸡、隐性白鸡血浆胆固醇含量进行了测定。结果表明:血浆胆固醇的含量从高到低依次为乌骨鸡,仙居鸡,隐性白鸡,萧山鸡,其中,乌骨鸡与隐性白鸡、萧山鸡,仙居鸡与萧山鸡间差异显著(p<0.05),其它鸡种间差异不显著。血浆胆固醇含量在性别间也存在差异,即公鸡高于母鸡。此外,研究还发现:利用血浆胆固醇含量作为辅助标志从理论上可以用于改进肉品中的胆固醇含量。     

Effect of method and time of first colostrum feeding on serum immunoglobulin concentration, health status and body weight gain in mithun (Bos frontalis) calves

The effect of method and time of first colostrum feeding on the concentration of serum immunoglobulin (Ig) was evaluated in mithun (Bos frontalis) calves. The hypotheses were that the variable method and time of first colostrum feeding might affect the level of serum Ig and in turn the growth performance and health status of the claves during the early age. The newborn calves were randomly allotted to one of the four experimental groups - G-1: allowed to suckle the dam at own choice, G-2: separated immediately after birth and allowed to suckle the dam first at 6 h and then at own choice, G-3: bottle fed ad libitum colostrum of its own dam first at 6 h and then at 6-h intervals until 24 h, G-4: bottle fed ad libitum colostrum of its own dam within 1 h, at 6 h and then at 6-h intervals until 24 h. The concentrations of IgG, IgM, and IgA were lowest (p < 0.01) at birth and increased following colostrum feeding irrespective of the experimental group. Highest concentrations of all the Ig classes were observed at 12-24 h after birth. The concentrations then transiently decreased from day 7 to 14, and then steadily increased after day 28. The concentrations of IgG (p < 0.01) and IgA (p < 0.05) were higher in G-1 in relation to the other groups during the first week after birth. Similarly, higher concentration of IgA (p < 0.05) was found in G-1 in relation to the other groups during the rest of the experimental period. The apparent absorption efficiency of colostral IgG was higher (p < 0.05) in G-4 in relation to G-3. Growth rate and health status were not influenced by the method and time of first colostrum feeding. In conclusion, a 6-h delay in the first colostrum feeding reduced the level of serum Ig noticeably.     

鸡传染性喉气管炎人工感染试验

为建立人工模拟自然感染途径诱发鸡传染性喉气管炎病理模型,本试验采用80日龄京粉鸡随机分成健康对照组和试验组,试验组又设10-4、10-5、10-6 3个不同稀释度的剂量组,每组20只,将鸡传染性喉气管炎病毒经口腔滴注到鸡喉气管内进行攻毒,观察攻毒结果并统计发病和死亡情况。结果表明,10-4攻毒剂量组发病时间为1～8 d,发病率100％,死亡率10％;10-5攻毒剂量组发病时间为2～8 d,发病率100％,死亡率５％;10-6攻毒剂量组发病时间为4～9 d,发病率90％,死亡率0％。各组鸡均表现张口呼吸,咳出带血黏液的临床症状,剖检后均可见气管粘膜肿胀、出血,其中10-5组比较典型。10-5组经喉气管内滴注可以引起鸡100％发病,潜伏期、临床症状和病理变化典型,并且与自然感染基本一致,可用作鸡传染性喉气管炎病理模型。     

Local and systemic cytokine responses during larval penetration in cattle experimentally infested with Hypoderma lineatum (Diptera: Oestridae)

Local and systemic cytokine responses were studied in 3 groups of cattle, with 4 animals each, experimentally infested with Hypoderma lineatum (De Villers) first instars (L1). The first group was undergoing a primary infestation (G-1), the second group was undergoing a secondary infestation (G-2) and the third group was infested for their third consecutive year (G-3). Cattle were infested with 25 L1 deposited on the skin. Blood and skin samples were taken at 0, 6, 12, 48, 96 and 144 h post-infestation (h.p.i.). Interleukin 10 (IL-10), IL-4 and interferon gamma (IFN-γ) production was studied by immunohistochemistry and sandwich ELISAs. IL-4⁺ cells showed a significant increase at 6 h.p.i. in both reinfested groups (G-2 and G-3) when compared with G-1. In all groups the number of IL-4⁺ cells decreased significantly at 48 h.p.i. IL-10⁺ cells increased in G-1 at 6 and 48 h.p.i., whereas in both reinfested groups increased at 12 h.p.i. with a peak at 48 h.p.i. IFN-γ⁺ cells showed a significant increment at 6 h.p.i. in all groups, followed by a rapid descent at 12 (G-1 and G-2) and 48 h.p.i. (G-3). Penetration of the skin by H. lineatum did not have any significant effect on IFN-γ serum concentrations and, except for IL-10 there were no correlation between local production and serum concentrations of cytokines. The increase of both Th1 (IFN-γ) and Th2-type cytokines (IL-4 and IL-10) indicates that bovine T-cell response during the first phases of the infestation by H. lineatum is apparently a Th0 response.     

13/17罗伯逊易位纯合子、杂合子猪及3个引进品种核仁组成区(Ag-NORs)的多态性

对 1 3/ 1 7易位纯合子猪、杂合子猪及杜洛克、长白、约克夏猪的核仁组成区 ( Ag-NORs)的多态性作了研究 ,结果表明 ,杜洛克、约克夏猪 Ag-NORs定位于 8号和 1 0号染色体的次缢痕区 ,而 1 3/ 1 7易位纯合子猪、1 3/ 1 7易位纯合子猪×约克夏猪 F1代 Ag-NORs的遗传方式符合孟德尔定律 ;Ag-NORs在细胞间、个体间及品种间数目均有差异 ,而且品种差异显著大于品种内个体间差异。 1 3/ 1 7易位纯合子猪、杂合子猪 ,以及长白、杜洛克、约克夏猪 Ag-NORs均数分别为 1 .99、1 .98、2 .0 0、2 .0 5、2 .0 6,说明 Ag-NORs在品种、个体及细胞间具有多态性。这种多态性与猪的起源和杂交育种时所用亲本品种的血缘成分有关 ,因此可作为遗传标记 ,用以分析家畜的亲缘关系     

晋南黄牛的染色体分析

以晋南黄牛为实验材料,做了染色体的常规分析。测量了各号染色体的相对长度、着丝点指数及臂比,并做了染色体的C带、R带及银染核仁组织者区(Ag-NORs)的分析。染色体常规染色及C带、R带分析表明:晋南黄牛公牛的核型为2n=60,XY。Y染色体有两种形态,一为近端着丝点染色体,另一为中着丝点染色体。Ag-NORs定位于第2、8、4、11、21(或22)及28号常染色体的末端,银染频率为每细胞6.109。讨论了另一品种双核型现象。认为晋南黄牛是我国北方普通牛与南方肩峰牛两大牛群汇合的交汇点之一。     

红豆杉干粉对产蛋初期仙居鸡生产性能和生化指标的影响

本试验旨在研究饲粮中添加不同水平的红豆杉干粉对产蛋初期仙居鸡的生产性能、血清脂质代谢和抗氧化指标的影响。选取400只140日龄仙居鸡,随机分成4组,每组5个重复,每个重复20只。对照组饲喂基础饲粮,试验组在基础日粮中分别添加2%、3%和4%红豆杉干粉,预试期7 d,正试期90 d。结果表明:在试验初期(1～30 d),各试验组平均日采食量(ADFI)均低于对照组(P<0.05),4%红豆杉干粉组的产蛋率低于对照组(P<0.05);在试验中期(31～60 d),各试验组ADFI、平均蛋重与对照组无显著差异, 4%红豆杉干粉组的产蛋率高于对照组(P<0.05),4%红豆杉干粉组的料蛋比低于对照组(P<0.05);在试验后期(61～90 d),3%红豆杉干粉组的平均日采食量高于对照组(P<0.05),3%红豆杉干粉组的平均蛋重低于对照组(P<0.05),4%红豆杉干粉组的产蛋率高于对照组(P<0.05);在试验46～90 d, 2%红豆杉干粉组平均日增重较对照组降低(P<0.05);各试验组血清总抗氧化能力高于对照组(P<0.05)。综上所述,饲粮中添加不同水平红豆杉干粉可以改善仙居鸡生产性能、血清生化指标和抗氧化能力,建议产蛋期日粮中添加4%红豆杉干粉。     

仙居三黄鸡产蛋期的生产性能

笼养条件下观察产蛋期的仙居三黄鸡不同体重对产蛋性能的影响。结果表明,体重最大组的只日产蛋量、产蛋率、蛋重、产蛋数、蛋长和蛋宽等指标均为最大;蛋重和蛋宽出现显著性差异,其余指标差异不显著;蛋重、蛋长和蛋宽与母鸡体重呈显著正相关。该研究结果可为仙居三黄鸡及其他蛋鸡的品质改良和开发利用提供理论依据。     

Bovine viral diarrhea virus (BVDV) infection in relation to fertility in heifers

In this study, blood serum and leukocyte samples were collected from 400 Holstein heifers, all of which appeared to be healthy. Antibodies (Ab) against bovine viral diarrhea virus (BVDV) were detected in 57 serum samples, and BVDV antigen (Ag) was detected in 38 leukocyte samples. There were statistically important differences between the average first insemination ages (FIT) of the BVDV (Ag-/Ab+) heifers (p<0.0001) (pregnant p<0.05, nonpregnant p<0.0001) and BVDV (Ag-/Ab-) heifers. The average conception rates (CR) of BVDV (Ag-/Ab+) heifers and BVDV (Ag-/Ab-) heifers were not significant statistically. There were statistically important differences in average FIT between persistent infected (PI) BVDV (Ag+/Ab-) heifers (p<0.0001; PI pregnant p<0.05, PI nonpregnant p<0.0001) and BVDV (Ag-/Ab-) heifers. No significant differences in average CR between PI BVDV (Ag+/Ab-) heifers and BVDV (Ag-/Ab-) heifers were found. The differences in average FIT between BVDV (Ag+/Ab+; p<0.0001; nonpregnant p<0.0001) and BVDV (Ag-/Ab-) heifers were important statistically. Although there were no BVDV (Ag+/Ab+) pregnant heifers, the differences in average CR between BVDV (Ag+/Ab+) pregnant heifers and BVDV (Ag-/Ab-) heifers were found to be statistically important (p<0.0001). We conclude that fertility is affected in heifers with BVDV (Ag-/Ab+, Ag+/Ab- and Ag+/Ab+).