骨代谢病乳牛血中1,25—二羟胆钙化醇（DHCC）含量的测定及发病…

为了探讨乳牛骨代谢病的发病机理，测定了骨代谢病乳牛血清１，２５－二羟胆钙化醇（ＤＨＣＣ）以及维生素Ｄ、羟脯氨酸的含量，并测定了肝、肾功能。结果表明，骨代谢病乳牛血清中维生素Ｄ含量升高，ＤＨＣＣ降低，羟脯氨酸降低，肝功能未见异常，肾功能发生了某些变化等。由此认为，乳牛骨代谢病是由肾功能障碍致维生素Ｄ转变为ＤＨＣＣ过程受阻，使ＤＨＣＣ含量降低引起的。其实质是骨基质分解降低，骨晶体即骨盐减少性疾病。     

乳牛体内维生素D3代谢与骨软病的研究

在北京效区某农场，选择１０头健康乳牛作为对照组，１０头具有骨营养不良的乳牛作为试验组，分别进行了饲料和血清钙，磷含量分析，血清ＡＫＰ活性及其同功酶，血清维生素Ｄ３及活性代谢产物等项目的检测，尾椎Ｘ线检查及维生素Ｄ３治疗试验等。结论如下：①该场乳牛发生的骨营养不良为贩质软化症，维生素Ｄ３其活性代谢产物缺乏是其主要病因；②血清２５－ＯＨ－Ｄ３和１，２５－（ＯＨ）２－Ｄ３是诊断乳牛维生素Ｄ营养状况和乳牛     

骨营养不良乳牛血清钙及血清游离羟脯氨酸含量测定

应用改良Fujii氏光电比色法和EDTANa2滴定法对88头乳牛进行血清钙、游离羟脯氨酸检到。结果表明：有明显或轻微合营养不良临床症状的乳牛(以下称病牛)与临床检查无骨营养不良症状的乳牛(以下称对照牛)比较，病牛的血清钙高于对照牛(P＜0．05)；血清游离羟脯氨酸亦明显高于对照牛(P＜0．01)。因此，血清钙升高可作为乳牛骨营养不良诊断的参考指标，而血清游离羟脯氨酸升高是乳牛骨营养不良早期诊断的指标。     

乳牛肝功能与维生素D3代谢及骨软病关系的研究

通过血常规，血清钙，无机磷，碱性磷酸酶活及其同工酶酶谱，尾椎Ｘ线检查等方法，在北京市郊区某农场，选出１０头健康成年黑白花乳牛作为对照组，１０头骨软病乳牛作为试验组。分别对其肝功能，血清维生素Ｄ３，２５－羟维生素Ｄ３（２５－ＯＨ－Ｄ３）和１，２５－双羟维生素Ｄ３（１，２５－（ＯＨ）２－Ｄ３）进行测定。结果表明，骨软病乳牛血清硫酸锌浊度及γ－球蛋白明显高于健康水平（Ｐ〈０．０５和Ｐ〈０．０１），而血清     

骨钙素在乳牛骨软病研究上的重要性

从北京某农场选取５头骨软病乳牛作为试验组，５头健康乳牛作为对照组，然后进行了血常规，血清学检测。结果表明，试验组乳牛血清钙水平呈下降趋势；血清无机磷水平显著下降。知清ＡＫＰ活性显著升高，其同工酶特征性酶谱中骨带染色谱宽变深；血清维生素Ｄ３活性代谢产物（２５－ＯＨ－Ｄ和１，２５－（ＰＨ）２－Ｄ３）均显著下降；血清骨钙素（ＢＧＰ）水平极显著下降。     

乳牛口服大量β-胡萝卜素对维生素D3及钙磷代谢的影响

６头健康成年荷斯坦乳牛被随机均分为２组。试验组牛第１周每头口服β－胡萝卜素２３．０ｇ,以后每周每头口服１１．５ｇ,对照组不做任何处理。试验期共８周。结果表明,试验组乳牛血清钙及无机磷水平呈下降趋势;血清维生素Ｄ３活性代谢产物２５－ＯＨ－Ｄ３和１,２５－（ＯＨ）２－Ｄ３均呈现明显下降;至第５周末,血液β－胡萝卜素水平最高,２５－ＯＨ－Ｄ３水平下降非常明显。据此认为,乳牛对β－胡萝卜素的吸收存在一阈值,大剂量的β－胡萝卜素进入机体,可能直接干扰维生素Ｄ３的羟化,使其活性代谢产物呈下降趋势,但由于吸收阈值的存在,其对维生素Ｄ３和骨骼钙磷代谢的干扰作用可得到一定程度的减缓。     

乳牛骨软症的调查研究

本文对哈尔滨奶牛场发生的以异嗜、跛行等为特征的乳牛疾病进行了调查研究,分析研究了日粮成分,临床表现,血清钙、无机磷、镁和羟脯氨酸的含量及变化,以及尾椎密度的测定值。结果表明,日粮中钙过多,磷、镁供给不足,钙、磷比例过大是致病的主要原因。并分析研究了乳牛血液生化指标的变化和尾椎骨密度的测定法对诊断和监测骨软症和钙、磷、镁代谢动态的意义。     

西宁市某奶牛场青年荷斯坦奶牛骨营养状况的调查

调查了西宁某奶牛场33头10－22月龄荷斯坦奶牛的骨营养状况，结果表明所有牛的血清羟脯氨酸、血清钙、血清无机磷的含量和碱性磷酸酶的活性均在正常范围，33头荷期坦奶牛骨营养状况良好。     

乳牛骨病血清乳酸脱氢酶及其同工酶的研究

乳牛骨代谢病是一个古老的疾病,是对乳牛业危害极大的三大疾病之一,到目前为止防治问题世界各国还都未能解决。本文通过对乳酸脱氢酶(LDH)及其同工酶测定结果的研究,发现在未出现典型临床症状前,心脏已经受到了损伤,当出现典型症状时,机体的肾、肺、肌肉、肝等组织器官都受到了损害。因此,我们认为本病为全身性复制性的疾病。彻底防止本病不能单纯以钙、磷、骨的代谢为重点,必须采用综合性防治措施方能奏效。     

含Ge^132促长素对乳牛生产和繁殖性能的影响

１９９８年１０月至１９９９年３月,在宁夏吴忠宁兰奶牛繁殖场,对试验组（ｎ＝１５）乳牛按每１００ｋｇ混合精料添加含Ｇｅ＾１３２促长素１．５ｋｇ,对照组（ｎ＝１５）添加畜禽用微量元素添加剂,共饲喂１８２ｄ。试验组与对照组相比,每头乳牛多产奶２５．５ｋｇ,可提高血清ＧＳＨ－ＰＸ、ＣｕＺｎ－ＳＯＤ的活性,降低血清ＭＤＡ的含量,提高全血Ｇｅ＾１３２、Ｓｅ、Ｚｎ、Ｃｕ的含量,提高乳牛越冬抗春乏的能力及繁殖性能     

稻草或玉米秸秆替代苜蓿对奶牛氮代谢、血清生理生化指标及肝脏和肾脏组织形态变化的影响

本试验旨在研究稻草或玉米秸秆替代苜蓿对奶牛氮代谢、血清生理生化指标及肝脏和肾脏组织形态变化的影响。选择45头泌乳中期的经产健康荷斯坦奶牛,随机分成3组,每组15头牛。各组饲喂含不同粗饲料的饲粮,分别为苜蓿组(23%苜蓿干草+7%羊草,AH组)、玉米秸秆组(30%玉米秸秆,CS组)和稻草组(30%稻草,RS组),饲粮精粗比均为55∶45。试验期12周。结果表明:CS组和RS组奶牛的粪氮排泄量显著高于AH组(P0.05),RS组奶牛的尿氮排泄量显著高于AH组和CS组(P0.05)。RS组奶牛的血清尿素氮和肌酸酐含量显著高于AH组(P0.05)。RS组奶牛的血清总胆固醇含量显著高于AH组和CS组(P0.05)。CS组奶牛的血清谷丙转氨酶活性显著高于AH组(P0.05),而血清谷草转氨酶活性显著高于AH组和RS组(P0.05)。各组奶牛的肝脏、肾脏组织切片结构清晰,未见明显异常。由此可见,饲喂玉米秸秆或稻草粗饲料的奶牛粪氮、尿氮排泄量的增加导致奶牛氮的利用效率降低。各组奶牛肝脏和肾脏的组织形态无显著变化,但饲喂玉米秸秆或稻草饲粮可导致奶牛血清中反映肝脏、肾脏健康功能的指标升高。     

乳牛口服过量维生素A对维生素D3及钙磷代谢的影响

从北京郊区某农场选取１０头健康成年黑白花乳牛，随机分为试验（５头，每周每头口服维生素Ａ１００万单位）和对照（５头，不作任何处理）两组。８周以后检测发现，试验组血清钙和无机磷水平呈下降趋势；尾椎骨皮质变薄，密度下降，呈现骨质吸收现象；血清碱性磷酸酶显著下降（Ｐ＜０．０５）；其活性代谢产物２５－羟维生素Ｄ３（２５－ＯＨ－Ｄ３）极显著下降（Ｐ＜０．０１）；１，２５－二羟维生素Ｄ３［１，２５－（ＯＨ）２－     

Effect of dietary Ximenia caffra kernel meal on blood and liver metabolic substrate content and the general clinical biochemistry of Sprague Dawley rats

We investigated (at the University of the Witwatersrand: GPS coordinates 26°10′ 52.96″S; 28°2′ 33.61″E) the effects of substituting soya bean meal (SBM) with Ximenia caffra kernel meal (XCKM) as a dietary protein source on blood and liver metabolic substrates content, serum markers of liver and kidney function and the general clinical biochemistry of Sprague Dawley (SD) rats. Five diets with similar energy and protein content were formulated (D1–D5) where XCKM replaced SBM on a crude protein basis at 0, 25, 50, 75 and 100%. Forty weanling male SD rats were randomly assigned to diets D1–D5, fed for 37 days and weighed twice weekly. The rats were then fasted overnight, and fasting blood glucose and triglyceride concentrations were determined from tail‐vein‐drawn blood. Immediately thereafter, the rats were euthanised and blood was collected via cardiac puncture. Serum was used to assay for markers of the general health profile. Livers were removed and weighed, and samples were used to determine lipid and glycogen content. Rats fed D4 (75% substitution level) had significantly lower (p < 0.05) blood triglyceride content compared with rats fed D2 (25% level of substitution). The substitution of SBM with XCKM did not affect (p > 0.05) fasting blood glucose and cholesterol concentrations, liver glycogen and lipid content. Additionally, it had no effect (p > 0.05) on serum activity/concentration of surrogate markers of liver (alanine aminotransferase and alkaline phosphatase activity and urea, total bilirubin, globulin and albumin concentrations) and kidney (phosphorus, calcium and creatinine concentrations) function and the general clinical biochemistry of the rats. Defatted XCKM could substitute SBM in rat diets without compromising blood glucose and cholesterol homeostasis, liver and kidney function and the general clinical biochemistry of growing male Sprague Dawley rats.     

酮病、脂肪肝奶牛胰岛素受体mRNA丰度

选择自然发生的酮病奶牛、脂肪肝奶牛和正常围产期荷斯坦奶牛（对照）各5头，通过手术方法采取其肝脏样品，采用半定量RT—PCR方法检测了这3组奶牛肝胜样品胰岛素受体（InsR）mRNA丰度的变化。结果表明，酮痛奶牛InsRmRNA相对表达量低于正常对照奶牛，而高于脂肪肝奶牛；脂肪肝奶牛InsR mRNA相对表达量低于正常对照奶牛和酮病奶牛（P〈0．05）。可见，酮病奶牛InsR mRNA相对表达量下降，提示此有利于酮病奶牛糖异生和脂肪动员，从而缓解能量负平衡；脂肪肝奶牛InsR mRNA相对表达量降低，提示奶牛胰岛素应答显著减弱，此时奶牛可能发生了胰岛素抵抗。     

大豆黄酮对奶牛免疫功能和血清及乳中几种激素水平的影响

研究口服大豆黄酮对奶牛免疫功能和血清及乳中生长激素(GH)、催乳素(PRL)、生长抑素(SS)水平的影响。结果表明：1)大豆黄酮能明显提高血清及乳中特异性抗体水平,表明奶牛整体和乳腺器官的体液免疫功能明显增强。2)奶牛血清及乳中GH、PRL含量明显高于对照组,而血清SS含量显著低于对照组。本实验结果提示垂体GH、PRL和体内SS可能参与了大豆黄酮对奶牛免疫功能的调节过程。     

缺磷症和肝功障碍奶牛血清碱性磷酸酶同功酶的诊断价值

本文应用聚丙烯酰胺凝胶圆盘电泳分析了81头健康、26头缺磷症、30头肝功障碍和17头缺磷症伴肝功障碍牛的血清AKP同功酶,并以热灭活试验鉴定其组织来源,探讨了该酶对奶牛缺磷症和肝功障碍的诊断价值。结果表明,健康和病牛血清中均有5条带,其中快带(SF)和慢-1(SS-1)存在于全部血清样中,其余3条慢带仅在部分血清中出现。具有诊断意义的SF和SS-1分别来源于肝脏和骨骼。健康牛的肝带和骨带均无弥散现象,两带间有明显间隔;缺磷症牛的骨带弥散并与肝带相连,形成一条宽而着色深的酶带;肝功障碍牛的肝带弥散,着色加深,但与骨带有间隙;缺磷症伴肝功障碍牛的肝带和骨带均有弥散,形成一条很宽而着色很深的酶带。上述酶谱变化可作为奶牛缺磷症和(或)肝功障碍的重要诊断指标。     

Chronic copper poisoning in two Holstein cows

Chronic copper poisoning with an acute hemolytic crisis is described in 2 mature Holstein dairy cows from separate herds. Toxic concentrations of copper were present in the serum and in liver and kidney tissues of each cow. There was no history of environmental or dietary exposure to excessive quantities of copper. No further clinical cases of chronic copper toxicosis were observed in the herds. As well as massive hemolysis, in both cows there was involvement of other organ systems including the liver and kidneys which contributed to the clinical course of the disease.     

Variability of serum bile acid concentrations over time in dairy cattle, and effect of feed deprivation on the variability.

Twelve nonlactating dairy cows, free of signs of liver disease and with normal serum activities of liver-derived enzymes and normal liver biopsy tissue, were examined over a 72-hour period for serum total bile acid concentrations. The cattle were fed hay twice daily, and blood samples were obtained every hour for 24 hours, every other hour for 24 hours, then every hour for 24 hours. After 3 weeks, the study was repeated on 6 of the cattle, thus providing data for eighteen 72-hour periods. Serum bile acid concentration varied greatly over the 72 hours, with the range being from one third to 3 times the median. There were variations by as much as 60 mumol/L from 1 hour to the next. After another 3 weeks, 8 of the cattle were deprived of hay for 48 hours and then fed hay morning and afternoon of the third (last) day of the study. There was no significant reduction in bile acid concentration after withholding the hay, but the variability was reduced (P = 0.02) during the last 20 hours of the hay-deprivation period. In 3 ancillary studies, serum bile acid concentrations were examined over a 48-hour period in 2 cows in early lactation, 3 cows in midlactation, and two 6-month-old heifers. The cows were fed hay and grain twice daily, and the heifers were fed only hay twice daily. In comparison with values for the 12 nonlactating cows fed hay twice daily, mean serum bile acid concentration in the recently freshened cows was significantly (P < 0.002) higher (62.9 vs 22.0 mumol/L).(ABSTRACT TRUNCATED AT 250 WORDS)     

Investigation on the Distribution and Analysis on Formation Cause of Cystic Ovarian Disease in Dairy Cows

In order to explore the incidence,pathogenic factors and the formation mechanism of cystic ovarian disease (COD) in Beijing scale dairy farm,we used the rectal examination and ultrasound diagnosis,combined with the dairy parity,calving season and serum biochemical indices and hormone levels to investigate the distribution,influencing factors and formation cause of cow ovarian cysts.The results showed that the incidence of cystic ovarian disease (COD) was 10.73% in the testing dairy herds and the incidence of COD was associated with the parities.The incidence rate of ovarian cyst in the cows calving in the summer (51.06%) was higher than those calving in the spring (8.51%) and winter (17.02%).Insulin,IGF-1 and E₂ were closely related with the formation of the cow ovarian cyst.The average concentrations of serum insulin and IGF-1 in cows with ovarian cysts were significantly lower than those of normal cows(P < 0.05),but the average concentration of serum E₂ was significantly higher than that of normal cows(P < 0.05).This study provided reliable basis for the prevention and treatment of cow ovarian cyst.