沈阳市某乳业公司奶牛钙、磷、β-胡萝卜素盈缺状况检查

对沈阳市某乳业公司七个奶牛场牛群血中钙、磷、β-胡萝卜素含量进行抽检，从全群3，000多头成母牛中共抽检350头奶牛，其中包括84头高产奶牛、77头干奶牛、92头产后牛和97头有病牛。结果表明：全群牛血中钙、磷的平均含量偏低，血钙的最高值、平均值和最低值分别为3．32mmol／l、2．26 0．44mmol／l和1．53mmol／l，血磷的最高值、平均值和最低值分别为2．71mmol／l、1．72 0．51mmol／l和0．84mmol／l；血中钙、磷比例不当，其最大值、平均值和最小值分别为3．96：1．0、1．70：1．0和0．645：1．0：血中钙、磷含量乘积偏低，其最高值、平均值和最低值分别为63．74、48．20和24．50；血中β-胡萝卜素含量不足，其最高值、平均值和最低值分别为657μg／100ml、278．69 201.78μg／100ml和52μg／100ml，其中高产牛血中含量相对较高。     

围产期奶牛几种血液生理生化指标监测

为了监测和诊断围产期奶牛常见营养代谢病,分别对产前15d、产前7d、产前1d、产后1d、产后7d、产后15d各10头共计60头围产期奶牛进行血液生理生化指标检测。结果显示,在整个围产期内奶牛血液中白细胞数、红细胞数、血红蛋白含量和红细胞压积差异不显著,不能作为围产期奶牛营养代谢病的监测依据。产前1d奶牛血清游离脂肪酸含量最低,为460.76±268.34μmol/L,与产前15d、产后7d、产后15d比较差异极显著(P<0.01)。产后7d奶牛血清葡萄糖含量最低,为2.12±0.35mmol/L,与其他时间测定值比较差异极显著(P<0.01)。产后1d奶牛血清中门冬氨酸氨基转移酶的含量最高,为15.33±3.24U/L,与产前15d、产前7d比较差异极显著(P<0.01)。产后15d奶牛血清中谷丙转氨酶活性和甘油三酯含量升高,分别为14.10±4.40U/L和0.90±0.14mmol/L,与产前不同时期比较差异极显著(P<0.01)。产后1d血清Ca含量降至最低值,为1.76±0.32mmol/L,血清羟脯氨酸含量和碱性磷酸酶活性升高,分别为25.50±7.90μmol/L和85.13±7.57IU/L,与产前不同时期比较差异极显著(P<0.01)。结果表明,利用血清游离脂肪酸、血清葡萄糖含量和血清门冬氨酸氨基转移酶活性,按公式计算Y值可作为诊断奶牛脂肪肝的依据。奶牛血清钙含量降低,血清羟脯氨酸含量和血清碱性磷酸酶活性升高可作为奶牛骨营养不良的诊断依据。尿酮体监测可作为奶牛酮病的诊断依据。     

上海地区奶牛产后低钙血症及酮病发病率调查

本研究对上海地区9个牧场奶牛产后低钙血症和酮病的发病率进行了调查,结果表明:奶牛产后12 h内的低钙血症发病率平均为86.1%,血钙平均浓度为(1.82±0.02)mmol/L,产后3~7 d低钙血症发病率平均为35.2%,血钙平均浓度为(2.05±0.01)mmol/L,表明随着泌乳天数的增加,低钙血症有缓解趋势。奶牛产后12 h内酮病发病率平均为5.5%,血液β-羟丁酸(BHBA)平均浓度为(0.68±0.04)mmol/L,产后3~7 d酮病发病率平均为16.3%,血液BHBA平均浓度为(0.98±0.07)mmol/L,表明随着泌乳天数增加能量负平衡有加重趋势。奶牛产后12 h内高游离脂肪酸(NEFA)发生率平均为49.4%,血液NEFA平均浓度为(0.76±0.03)Meq/L,产后3~7 d高NEFA发生率平均为41.3%,血液NEFA平均浓度为(0.71±0.03)Meq/L,表明泌乳初期高NEFA发生率远高于酮病发病率,随着泌乳天数增加血液NEFA浓度有下降趋势。奶牛产后血液中钙的浓度与NEFA浓度呈极显著负相关(P0.01),血液中NEFA浓度与BHBA浓度呈极显著正相关(P0.01)。     

奶牛护蹄有三招

(一)合理配合日粮日粮中钙、磷的配比对奶牛蹄影响很大.奶牛日粮中低钙还是低磷,都会引起骨质疏松.高钙高磷会对锌等元素起拮抗作用,而缺锌等元素会影响蹄的角质化,容易发生腐蹄,所以高钙高磷也会引起奶牛蹄病.所以奶牛日粮中钙、磷比要合适(钙磷比为2:1至1.3:1为宜).日粮中缺乏维生素D等微量元素,也是引起发病的主要原因,所以要保证喂给优质的粗饲料.精料喂量过多,特别是碳水化合物过多,引起瘤胃酸度过高,是蹄叶炎发病的重要原因;如果精料少,蛋白质比例偏低会导致蹄生长异常进而发生蹄变形、蹄裂等蹄病.因此合理的精粗比也是关键,奶牛的精粗比是随着产奶的不同时期而定.一般成母牛精粗为30:70,泌乳前、中、后期的精粗比分别为60:40、50:50、40:60.     

青海省民和县某奶牛养殖小区隐性酮病的调查研究

用水杨酸比色法测定青海民和县某奶牛养殖小区A、B两个群体(50头)奶牛的血、乳、尿中的酮体,其平均含量分别为血酮1.163mmol/L±0.421mmol/L,乳酮3.041mmol/L±1.214 mmol/L,尿酮3.232mmol/L±1.713mmol/L.结果表明,其中有9头奶牛有隐性酮病,其乳酮和尿酮呈较强负相关(r=-0.60147).     

青海省某奶牛场隐性酮病的调查研究

用水杨酸比色法测定青海民和县某奶牛场A、B两个群体50头奶牛的血、乳和尿中的酮体,其含量分别为血酮1.163 mmol/L±0.421 mmol/L,乳酮3.041 mmol/L±1.214 mmol/L和尿酮3.232 mmol/L±1.713 mmol/L。结果表明,其中有9头奶牛有隐性酮病,其乳酮和尿酮的相关系数γ=-0.60147。     

广东省某奶牛场隐性酮病的调查

用水杨酸比色法测定广东佛山某奶牛场K、I 两个群体(27 头)奶牛的血、乳、尿中的酮体,其含量分别为血酮 1.155 mmol/L±0. 511 mmol/L,乳酮 2. 904 mmol/L±1.311 mmol/L,尿酮 3.127 mmol/L±1.814mmol/L。结果表明,其中有 6 头奶牛有隐性酮病, 其乳酮和尿酮的相关系数 r 为-0.59038。     

奶牛肢蹄病的发生原因及防治措施

1发病原因日粮中缺钙、缺磷,或是高钙低磷、高磷低钙,都容易导致钙磷代谢障碍,从而引起奶牛肢蹄病。维生素D不足或活性下降时,可引起钙、磷代谢障碍。某些曲霉菌素中毒会干扰维生素D的活性,即使钙、磷充足也不能被很好利用,以致引发奶牛肢蹄病。粗饲料特别是干草品质低劣,也是引发奶牛肢蹄病的重要原因之一。     

高产奶牛血清镁含量分析

为调查南宁地区某奶牛场奶牛血清镁含量及其是否与该场奶牛蹄病有关,选取40头健康奶牛和46头蹄病奶牛,采用原子吸收分光光度法分析每头牛血清镁含量,结果表明全部被检牛血清镁平均含量为22.72±3.11mg/L;健康组与蹄病组奶牛血清镁含量分别为23.02±3.19mg/L和22.45±3.09mg/L,两组间差异不显著(P＞0.05).     

奶牛蹄病发生原因及综合防治

正奶牛蹄病是影响奶牛健康和生产性能的一种常见病,临床上主要有蹄变形和腐蹄病两种。据报道,我国奶牛蹄病的发病率在30%以上,夏季炎热地区尤为严重。山西省朔州市是一个奶牛养殖大市,2014年年底,全市奶牛存栏量占到全省的一半。因此,做好奶牛蹄部的卫生保健,预防蹄部疾病,对提高该市奶牛养殖经济效益意义重大。一、奶牛蹄病发生原因1.营养因素。(1)钙磷比例不当或不     

西杂牛与哈萨克牛育肥对比试验

对 14～ 17月龄 12头西杂牛一代公牛和 12头哈萨克公牛进行 12 0天的育肥 ,西杂一代公牛平均日增重 986 5g±12 0 4 5 g ,屠宰率 5 5 2 %,净肉率 44 2 %;哈萨克公牛日增重 498 2 g± 96 3 0g ,屠宰率 46 5 %,净肉率 3 6 4 %。西杂一代公牛比哈萨克公牛日增重提高 98 0 %,屠宰率和净肉率分别提高 8 7和 7 8个百分点。     

Dry cow nutrition. The key to improving fresh cow performance

Evidence supports the concept of the dry period being a critical component to lactation preparation rather than an insignificant rest period between lactations. Required nutrient amounts for the dry cow are the sum of maintenance, pregnancy, and reserve replenishment needs with additional requirements for growth during the first two pregnancies. Maintenance energy requirements can be dramatically increased by level of activity and adverse environmental conditions. A wide variety of feed ingredients can be successfully fed to dry cows as long as rations are appropriately formulated to meet energy, protein, mineral, and vitamin requirements. A early and close-up dry program best matches increasing pregnancy requirements and declining intake capacity with management capabilities. The early dry cow ration is formulated for high fiber/low energy density while the close-up ration contains higher energy density with less fiber. Both rations contain sufficient other nutrients based on determined intake. This two-group system provides maximal flexibility in managing for optimum body condition at calving. Environmental stresses and dramatic dietary changes should be minimized during the transition period from late gestation to lactation. A sound dry cow program results from integration of quality nutrition and cow management practices as described. A dry cow program that enacts these guidelines should result in reduced incidence of clinical mastitis, successfully complete pregnancy with a viable calf, maximize genetic potential for milk production, minimize incidence of health disorders, and allows cows to breed back within an economically optimum time interval. Overall, a sound dry cow program is a critical key to improved fresh cow performance.     

Effect of calf weaning age and cow supplementation on cow productivity

Five years of data were collected on 124 Brangus-type cows to evaluate weaning calves at 8.5 or 10.5 mo of age and winter supplementation of the brood cow with 2.25 kg of molasses daily. Cows with calves weaned at 10.5 mg of age gained 14 kg less weight (P less than .01) during the late nursing period than did cows from which calves were earlier weaned. Age of calf at weaning had no effect on cow reproduction, but calves weaned at 10.5 mo were 2 to 3 d younger (P less than .06) and 5.3 kg lighter (P less than .05) at 8.5 mo of age. During the last 2 mo of nursing, calves weaned at 10.5 mo of age gained 37.2 kg and had a 31.9-kg heavier weaning weight than calves weaned at 8.5 mo of age. Molasses supplementation resulted in differences (P less than .01) in cow weight changes. Cows fed molasses had calving percentages 5 to 7 units higher (P less than .30) than cows not fed molasses. Feeding cows molasses for 145 d throughout the calving and breeding season increased calf weaning weight 7.7 (P less than .02) and 11.2 (P less than .03) kg, respectively, at 8.5 and 10.5 mo of age over the nonsupplemented controls.     

奶牛乳房炎多联苗(B)的临床免疫试验

用奶牛乳房炎多联苗 (B)免疫家兔 ,14 d血清中金黄色葡萄球菌抗体效价可达 1∶ 8,2 8d抗体水平明显升高 ,可达 1∶ 32 ,注苗后 35 d攻毒 ,攻毒后 2 d保护率为 93.3% (14 /15 ) ,自然保护率为 2 0 % (1/5 ) ,10 d保护率为 6 6 .6 % (10 /15 ) ,自然保护率为 2 0 % (1/5 ) ;用多联苗 (B)臀部肌肉注射免疫泌乳牛 ,试验期间 4个月内 ,3ml剂量组临床型乳房炎月平均发病率为 11.0 9% ,其对照组为 2 0 .19% ,发病率降低 4 5 .2 9% ,差异极显著 (P<0 .0 1) ;5 m l剂量组月平均发病率为 13.0 1% ,其对照组为 31.36 % ,发病率降低 5 8.5 1% ,差异极显著 (P<0 .0 1) ;3ml剂量组与 5 m l剂量组之间发病率无明显差异 (P>0 .0 5 ) ;注苗后泌乳牛血清抗体水平可持续 4个月 ,且 30 d时效价水平最高。     

奶牛胚胎移植中以改良牛做受体牛的试验

为了加快良种牛扩群步伐，促进养牛业的快速发展，目前，单靠扩大牛群规模来提高肉、奶产量是不现实的，必须通过提高牛个体肉、奶单产，即提高牛群质量来加以解决。就奶牛业来讲，依靠从国外引进活畜形式改良本地奶牛品种存在着价格昂贵、运输困难、检疫繁琐等诸多问题，