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11.
Growth of mastitis pathogenic bacteria was measured in bovine whey samples by a turbidometric microtechnique. Whey from mastitis cows supported growth as compared with whey prepared from normal milk. Blood proteins leak into milk during mastitis. A study was undertaken to analyze which molecules from blood would promote bacterial growth in whey Fractions containing hemoglobin showed a distinct growth-promoting effect. An inadequate iron supply is one of the restricting growth factors for bacteria in milk. By utilizing heme-compounds the pathogens can by-pass the effect of antimicrobial iron-binding present in milk in the form of lactoferrin.  相似文献   
12.
The relationship between some skin characteristics and hemoglobin values during the growth period were statistically examined in standard male minks. Significant correlations) (P < 0.05–0.001) were found between the hemoglobin concentrations determined at 3 points during the growth period (in July, August and November) and the density and colour of underfur, and skin length, respectively. According to the study even the early hemoglobin values in July and August have a significant influence on the size and quality of the pelt. Mink kits with low hemoglobin values are liable to develop a winter fur coat with defective pigmentation and hair structure of the underfur. Anemic minks develop the most extreme stage of the pigmentation defect and these so-called cotton fur skins have little value in the fur garment industry. When these abnormal hemoglobin values are recognized at an early stage, cotton fur skins may be avoided, and larger skins of better quality may be produced.  相似文献   
13.
用常规方法对同一海拔高度不同发育期牦牛几项指标进行测定。结果:随着牦牛年龄的增长血液中Hb含量、HCT值逐渐增加,而RBC明显降低,差异显著(P<0.05),即随年龄的增长Hb、HCT与RBC的变化呈负相关;心肌和骨骼肌Mb含量随着年龄的增长均呈逐渐递增的趋势,心肌中Mb含量均显著高于骨骼肌,差异显著(P<0.05)。结论:牦牛在生长发育过程中逐渐增加血液中Hb、HCT和骨骼肌、心肌中Mb含量增强机体有氧代谢机制。  相似文献   
14.
The oxygen binding properties of whole blood and hemoglobin were studied in three phylogenetically distant tropical teleosts inhabiting freshwater billabongs that exhibit marked seasonal oxygen stratification. The water breathing saratoga (Scleropages jardinii, Family Osteoglossidae), derived from an ancient divergence of the stem line leading to all other extant teleosts, has a low blood oxygen carrying capacity, Bohr and Root effect, and a high blood oxygen affinity. Erythrocytes contain a single major hemoglobin component, and equimolar concentrations of ATP and GTP. The tarpon (Megalops cyprinoides, Family Megalopidae), a facultative air-breather, has the highest blood oxygen carrying capacity and Bohr effect, and a low blood oxygen affinity and Root effect. Erythrocytes contain a single major hemoglobin and ATP as a putative regulator of hemoglobin oxygen affinity. Barramundi (Lates calcarifer, Family Centropomidae), is an obligate water-breather with intermediate blood oxygen binding properties, and the smallest Root effect. Erythrocytes contain at least 7 hemoglobins, and equimolar concentrations of ATP and GTP. Functional properties of these three blood oxygen transport systems are considered in terms of the respiratory environment and demand for oxygen. Our interpretation supports the hypothesis that the process of speciation can lead to divergence in physiological mechanisms, irrespective of past or present selection pressures.  相似文献   
15.
Hemoglobin (Hb) multiplicity is a commonly used index of phylogenetic differentiation and molecular adaptation in fish. Despite improvements in technologies for characterizing protein structure, our knowledge of the component composition of the Hb system in rainbow trout, Oncorhychus mykiss, has remained almost unchanged through three decades. The Hb is considered to consist of four components, of which two (HbI and HbIV) have been extensively characterised with regard to structure and function. Using a variety of molecular techniques we demonstrate the presence of at least nine different Hb fractions composed of nine (five α and four β globin) chains, and that HbI and HbIV consist of two and five individual components, respectively. These findings indicate that the published data on trout HbI and HbIV refer to mixtures of isoHbs and need to be reappraised. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
16.
Hematological status was examined in rainbow trout,Oncorhynchus mykiss, held for 3–4 weeks under temperature, photoperiod and PO 2 conditions approximating those of their winter, spring and summer habitats. The most striking change observed was in red cell population composition. In winter fish mature cells were predominant; juvenile and developing erythrocytes characterized spring and summer animals. Hemoglobin, hematocrit and both mean erythrocytic volume and hemoglobin were modestly lower in spring and summer than in winter fish. Red cell numbers were not significantly affected. These observations suggest that avoidance of viscosity-based increases in circulatory work cost is more advantageous than elevation of blood O2-carrying capacity. Although hemoglobin isomorph profiles were significantly altered, there is little evidence that such changes are of critical adaptive importance. Given presumed age-based reduction in gas transport effectiveness, the replacement of mature and senescent cells by more metabolically-competent juvenile cells appears to be the pivotal event in hematological response. Leucocyte counts were significantly elevated in spring and summer as compared to winter fish. Lymphocyte/heterophil ratios declined from 8.27 in winter fish to 3.13 in summer trout. Thrombocyte, monocyte, eosinophil and basophil abundances were little changed.  相似文献   
17.
Goldfish,Carassius auratus, were acclimated for 2 to 3.5 weeks to three temperature regimes: [1] temporally-constant (10, 20 and 30°C), [2] diurnally-cycling (20 ± 10°C) and [3] randomly-fluctuating (± 2°C at approximately 2h intervals between extremes of 10 and 30°C). No significant differences in hematocrit were evident. Hemoglobin levels in fish at constant 30°C and under randomly fluctuating temperature were significantly elevated. Of the three hemoglobin isomorphs observed, the two minor components (G1, G3) tended to decrease in relative abundance with increase in constant temperature, but increased under varying temperature regimes. The converse was true of the principal hemoglobin, G2. Extent of isomorph variation was correlated with extent of temperature variability. These observations confirm that temperature variability significantly effects thermoacclimatory response. The functional significance of changes in isomorph abundances during the acclimatory process is considered.  相似文献   
18.
中国水牛血红蛋白多态性及命名研究   总被引:2,自引:1,他引:2  
采用醋酸纤维薄膜法首次系统分析了中国12个水牛地方类群1071头水牛的血红蛋白多态性。结果表明,中国水牛血红蛋白受Hb^A,Hb^B,Hb^C3个等位基因控制,其频率分别为0.0761,0.8852和0.0387,Hb^C基因系首次命名。聚类分析表明,中国水牛名地方类群间亲缘关系较近。  相似文献   
19.
 从大鲵皮肤cDNA文库中分离获得大鲵α1 血红蛋白基因全长cDNA序列,生物信息学分析表明,大鲵α 血红蛋白基因全长cDNA序列为594 bp,开放阅读框共432 bp,编码144个氨基酸,编码的大鲵α1 血红蛋白推测的理论分子量为16048.3 u,等电点为6.44。氨基酸组成中酸性氨基酸11.9%,中性氨基酸69.9%,碱性氨基酸18.2%。结构分析表明,该蛋白没有信号肽,但在100~122个氨基酸处以及98~122个氨基酸处分别有由里向外、由外向里的跨膜螺旋区,二级结构以α 螺旋为主。氨基酸序进行同源性列比对表明与人、猕猴的亲缘关系最近,和牛蛙的亲缘关系最低只有35%。荧光定量PCR结果表明,α1 血红蛋白基因在肌肉中表达量最高,在胃中最低。  相似文献   
20.
选取120头28日龄断奶仔猪,随机分成4个处理组,即对照组和3个试验组,每组3个重复,每个重复10头。对照组饲喂基础日粮,试验1组、试验2组、试验3组分别饲喂基础日粮中血红素铁净添加量为27.5mg/kg、55.0mg/kg、85.0mg/kg的3种试验日粮,研究日粮中添加血红素铁对断奶仔猪的生长性能、血液指标(血红蛋白浓度、免疫球蛋白浓度)的影响。试验正试期14d。结果表明,血红素铁各添加量组均能够提高仔猪的生长性能,日粮中血红素铁添加量为55mg/kg时,仔猪平均日增重、饲料转化率较对照组分别提高12.02%和10.27%(P<0.05)。血红素铁对断奶仔猪有良好的促生长作用,也在一定程度上提高了仔猪血液中血红蛋白和IgG浓度。  相似文献   
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