酒精阳性乳奶牛血清和全乳钙、镁含量变化

目的:为研究不同程度的酒精阳性乳患牛血清和乳中的钙、镁水平。方法:首先剔除加州乳房炎检测法阳性的奶牛,用68%的酒精全群检测酒精阳性乳,用72%的酒精测定68%的酒精阴性牛乳,再用75%的酒精测定72%的酒精阴性牛乳,在75%酒精阴性牛群(对照组)、阳性牛群,72%酒精阳性牛群和68%酒精阳性牛群各选择产奶量、胎次、年龄、泌乳期相近的奶牛6头。分别组成1、2、3、4组。连续3周对各组奶牛进行颈静脉采血,分离血清,采集鲜乳,测定血清和乳中钙、镁的含量。结果:酒精阳性乳患牛血清和乳中钙、镁含量增加。结论:酒精阳性乳患牛体内钙、镁代谢紊乱,过多的钙、镁中和酪蛋白微胶粒表面的电荷,导致酪蛋白稳定性下降,致使乳胶体聚集能力增强,易导致酒精阳性乳的形成。     

低酸度酒精阳性乳患牛颈、乳静脉中矿物质含量变化的研究

通过对酒精阳性乳患牛及正常牛颈、乳静脉中8种离子含量的测定与对比分析,发现酒精阳性乳患牛的乳腺分泌上皮细胞选择性吸收钠、钾、钙、镁的功能异常,进而引起乳中的相应含量发生变化;以及患牛乳腺组织利用锌、铜、锰、铁的量发生了变化。这对深入探讨酒精阳性乳症的发生机理以及对患牛乳腺代谢的影响都提供了有力的证据。     

酒精阳性乳患牛泌乳相关激素含量的变化

本试验对酒精阳性乳症患牛血清中6中激素的含量进行了检测,探讨酒精阳性乳症患牛内分泌机能的变化。结果表明:酒精阳性乳症患牛血清中皮质醇(Cort)、甲状旁腺素(PTH)、甲状腺素(T4)和催乳素(PRL)含量均极显著降低(P<0.01),三碘甲腺原氨酸(T3)含量显著降低(P<0.05),仅降钙素(CT)含量变化不明显(P>0.05)。激素含量的显著变化,说明酒精阳性乳症患牛存在内分泌紊乱现象。     

奶牛酒精阳性乳的发生及防治

奶牛酒精阳性乳是指用68％～72％的酒精与等量的牛乳混合后而产生微细颗粒或有絮状块的牛乳。多年来各乳制品厂大都延用酒精试验法来检验牛乳品质，凡发现酒精反应呈阳性皆按不合格品处理，致使一些品质稍差、但尚能利用的牛乳被废弃。     

奶牛酒精阳性乳

奶牛酒精阳性孔指用68％～72％的酒精与等量牛奶混合,会产生细微颗粒或絮状凝块,这种奶加热易凝固,是不合格奶,不能用作原料乳进行深加工,也不能销售,常被废弃,给奶业生产造成很大的经济损失。 一、病因 1.饲养管理失调,日粮成分不平衡,可消化粗蛋白和总消化养分过量     

酒精阳性乳的预防措施

酒精阳性乳是指用68％～72％中性酒精与等量的牛奶,在试管或器皿中予以充分混合后而产生微细颗粒或絮状凝块的牛奶。根据酒精阳性乳酸度的差异,可将其分为高酸度酒精阳性乳（酸度在0．181％以上）和低酸度酒精阳性乳（酸度在0．181％以下）两种。     

奶牛酒精阳性乳的防治措施

酒精阳性乳是指与68%～70%酒精发生凝结现象的乳的总称。分高酸度和低酸度酒精阳性乳两种。     

低酸度酒精阳性乳患牛血清蛋白组成分析

本实验采用醋酸纤维素薄膜电泳法分离了低酸度酒精阳性乳患牛血清中各蛋白组成成分,并测定了血清蛋白组份的相对百分含量.结果表明:酒精阳性乳患牛血清总蛋白含量没有显著变化(P＞0.05);各血清蛋白组分中,清蛋白、α-球蛋白没有显著的变化(P＞0.05);但β-球蛋白极显著升高(P＜0.01),γ-球蛋白显著升高(P＜0.05).由此可见,酒精阳性乳患牛体内血清蛋白组分发生了变化,这种变化可能是酒精阳性乳患牛体内氧化损伤及甲状腺机能降低所致.     

谈酒精阳性乳

酒精阳性乳俗称酸乳,是指从乳房挤出的奶酸度在11-18°(T吉尔涅尔度,指中和100ml牛乳中的酸所需的0.1mol/l的氢氧化钠溶液的毫升数。)之间,与68-70(%羊乳用60-65%)酒精等量混合,产生细细小絮片或凝固的乳。当前很多牛乳现场用酒精试验即为酒精阳性乳,本文就此谈了产生的原因、症状及防治要点。     

两例奶牛酒精阳性乳的诊治报告

酒精阳性乳是指刚从牛乳房挤出来的乳,在20℃温度下,与等量的68～70%酒精混合发生凝结现象的牛乳。分为高酸度和低酸度酒精阳性乳两种。高酸度酒精阳性乳:指乳的滴定酸度增高(0.2以上),与70%酒精凝固的乳。主要是在挤乳过程中,由于挤乳机管道、挤乳灌消毒不严,挤奶场环境卫生不良,牛奶保管、运输不当以及未及时冷却等,致使细菌繁殖、生长,乳糖分解成乳酸,乳酸升高,蛋白变性所致。     

黑白花奶牛血压测定及钠钾对血压的影响

本文应用弹簧式血压计测定了144头中国黑白花奶牛尾动脉压,并就添加钠钾对血压的影响作了初步探讨。结果表明,用此型血压计测定奶牛尾动脉压是可行的;成奶牛尾动脉收缩压为137.10+16.32mmHg,舒张压为44.63±14.72mmHg;日粮添加钠钾可使血清钠钾浓度显著升高,尾动脉收缩压显著升高(P<0.05),舒张压极显著升高(P<0.01);建议改血压计气袋为梯形,以减少气袋与尾动脉接触不紧对血压值的影响。     

Effect of Bospro on High and Mid-to-Low Milk Yielding Chinese-Holstein Cow

A total of 90 cows from two farms (farm A 30 cows, farm B 60 cows) were used to study the effect of Bospro on milk production, milk quality and subclinical mastitis incidence. The cows in the test group were supplied with 20 g of Bospro per head per day and meanwhile, the percentage of milk fat, protein and lactose and moisture of the milk samples were analysed. The results showed that the milk yield of both high production and mid-to-low milk producting cows increased by 3.3% to 5.3% respectively compared with their control group of cows, but there was no changes on the milk content between the treated and the control cows. The treated cows also showed an increased body weight (P>0.05) and significantly reduced incidence of mastitis, as Compared with that of the control group. The experiment dcmonstrats that Bospro can increase milk yield, but not at the expense of milk quality and body weight.     

提高泌乳盛期奶牛乳脂率与乳蛋白含量的营养调控研究

为研究提高奶牛乳脂率与乳蛋白含量的营养调控技术,选择体况、胎次、产犊时间、产奶量相近的泌乳盛期中国荷斯坦奶牛27头,采用L9(34)正交试验设计,进行了中性洗涤纤维(NDF)、小肠可消化蛋白(IDCP)、添加过瘤胃保护脂肪酸(RPFA)、过瘤胃保护氨基酸(RPAA)对泌乳盛期奶牛乳脂率与乳蛋白含量的影响试验.结果表明,日粮干物质(DM)中NDF41%、IDCP按我国<奶牛饲养标准>推荐量92%、脂肪酸钙150g/d、过瘤胃保护蛋氨酸8g/d+过瘤胃保护赖氨酸32g/d,可有效提高奶牛泌乳盛期的乳脂率与乳蛋白含量.     

牛奶和鸡蛋中抗生素残留规律研究

[目的]了解新疆地区奶牛和蛋鸡生产中常用抗生素类药物在牛奶和鸡蛋中的残留情况.[方法]按照新疆地区奶牛和蛋鸡生产中抗生素类药物的使用方法及剂量进行投放,采集牛奶及鸡蛋样品进行检测.[结果]青霉素钾在牛奶中的残留规律为停药1 d>5 d>3 d;头孢噻呋钠在牛奶中的残留规律为停药3 d>1 d>5 d;链霉素在牛奶中的残留规律为停药1 d>3 d>5 d;长效土霉素在牛奶中的残留量在停药1～11 d一直维持在175 μg/kg左右;停药1和3 d,酒石酸泰乐菌素在鸡蛋中的残留量为2 μg/kg左右;头孢噻呋钠在鸡蛋中的残留规律为停药7 d>5 d>3 d>1 d;环丙沙星在鸡蛋中的残留规律为停药11 d>7 d>5 d>1 d>3 d.[结论]除了长效土霉素外,其他药物在休药期内的残留量均低于中国和欧共体(EEC)规定的标准残留限量.     

日粮中添加不同处理及水平的VA对奶牛泌乳性能及乳中VA含量的影响

[目的]通过饲养试验,研究不同处理及添加剂量的维生素A对奶牛乳品质及乳中维生素A含量的影响。[方法]采用2×2随机试验设计,按照体重、泌乳量及胎次相近的原则,将24头奶牛随机分为4组,每组6头。各组在基础日粮中添加不同处理及水平的维生素A。[结果]奶牛日粮中维生素A的添加量由110 IU/kg BW提高至165 IU/kg BW,有明显减缓泌乳中后期奶牛日产奶量的下降及提高乳中维生素A含量的趋势,但其效果不如添加相同剂量的过瘤胃保护维生素A微胶囊。与未处理维生素A组相比,日粮中添加1101、65IU/kg BW过瘤胃保护维生素A微胶囊可以明显增加泌乳中后期奶牛的日产奶量,提高乳中维生素A含量,尤以165 IU/kg BW过瘤胃保护维生素A组的效果明显。[结论]奶牛饲喂过瘤胃保护维生素A能够有效提高奶牛的日产奶量,增加乳中维生素A浓度,增加日粮中维生素A的添加剂量也有增加奶牛生产性能及乳中维生素A的趋势。     

中药对围产期奶牛生产性能及血液生化指标的影响

为探明中药对围产期健康奶牛生产性能及血液生化指标的影响,选临床检查健康的围产期荷斯坦奶牛90头,按年龄、胎次和预产期相近的原则随机平均分成A、B、C 3组,A组:于预产期前15 d喂服中药加味四君子散(每头400 g/d),连用5 d,分娩后当天喂服益母生化散(每头400 g/d),连用2 d;B组:产前不喂服中药,分娩后当天喂服益母生化散(每头400 g/d)),连用2 d;C组为对照组,产前、产后均不喂服中药。各组奶牛分别测定干物质摄入量、日产奶量、乳成分及血液生化指标。结果显示:与对照组相比,A组奶牛干物质采食量增加10%以上(P<0.05),平均日产奶量提高10%以上(P<0.05),血清甘油三酯含量明显降低(P<0.05),血清葡萄糖、血清总蛋白和血清钙维持较高水平(P<0.05)。表明奶牛产前与产后喂服加味四君子散和益母生化散能有效改善血液生化指标并利于产后生产性能的充分发挥。     

Effects of Rumen Protected Methionine on Milk Yield and Milk Composition in Earlier Lactating Cow

A total of 12 mature healthy Holstein dairy cows of the nearly body weight （580±30） kg, milk yield （22.5±2.8） kg in the early stages of lactation were selected in this experiment. The cows were randomly divided into 2 groups, every group had 6 cows, every group had 6 repeats, and every repeat had 1 cow. Added 20 g protected methionine in earlier lactating cow food every day. The results showed that protected methionine increased milk yield by 10.83%, testing group milk yield was significantly different than that of control （P〈0.05）; protected methionine increased milk fat by 5.98%, testing group milk fat was significantly different than that of control （P〈0.05）; Milk protein increased by 2.15%, but bad insignificantly different （P〉0.05）; dry matter of milk had the tendency of decrease, but had insignificant difference （P〉0.05）.     

芦丁对奶牛泌乳性能和血清指标的影响

 【目的】研究了芦丁对奶牛产奶量、血清、泌乳相关激素等指标的影响,旨在寻找合适的添加量,为应用芦丁提高中国奶牛泌乳性能提供数据参考。【方法】选用生理状态等相近的泌乳高峰期经产中国荷斯坦奶牛20头,随机分成4组,每组5头。分别在基础日粮中每日每头添加芦丁0.0(对照组)、1.5、3.0、4.5mg?kg-1。试验期11周,其中预饲期1周,正试期10周。隔日记录试验牛的产奶量,并于试验第5、35、65日采集乳样进行乳成分分析,同日尾静脉抽取血液样品,根据产奶量的检测结果,选择效果最好组及对照组测定其血清生化指标、免疫指标及泌乳相关激素含量等。【结果】(1)与对照组相比,3.0mg?kg-1与4.5mg?kg-1芦丁处理组都显著提高了奶牛的产奶量(P＜0.05),而1.5 mg?kg-1芦丁处理组与对照组奶牛产奶量差异不显著(P>0.05);1.5 mg?kg-1芦丁处理和3.0 mg?kg-1处理乳脂率低于对照组(P＜0.05),4.5mg?kg-1芦丁处理乳脂率同对照组差异不显著(P＞0.05),各处理组间牛乳乳蛋白、乳糖、非脂固形物差异不显著(P＞0.05)(2)3.0mg?kg-1处理组血清溶菌酶含量高于对照组(P＜0.05),尿素氮水平第35、65日检测结果低于第5日检测结果(P＜0.05);该处理组奶牛血清谷丙转氨酶由第5日的22.88(IU?L-1)提高到第65日的25.38(IU?L-1),催乳素含量则由12.19ng?mL-1上升到13.94ng?mL-1,提高了14.36%;(3)3.0mg?kg-1处理组血清指标中,免疫球蛋白IgG、总蛋白、白蛋白、葡萄糖、皮质醇、谷草转氨酶、碱性磷酸酶含量与对照组比较差异不显著(P＞0.05);血清中雌激素、孕激素的水平同对照组相比差异不显著(P＞0.05),但孕激素水平呈现上升趋势。【结论】芦丁能够提高奶牛泌乳性能,同时保持奶品质,降低奶牛血清中尿素氮的水平,提高溶菌酶的含量。在本试验条件下,芦丁适宜添加量为3.0 mg?kg-1。     

Effect of Different Roughages on Milk Protein and Milk Fat Synthesis in Dairy Cows

The main purpose of this study was to determine the effect of a corn straw or mixed diet on milk production, milk composition and the expression of genes associated with lactation in mid-lactation Chinese Holstein cows. In this study, 10 healthy Chinese Holstein cows were randomly assigned to two groups and fed with different diets respectively, corn straw(CS) or mixed forage(MF) diet. CS group was fed roughage consisting of 53.8% corn straw only and the forge to concentrate(F : C) ratio [dry matter(DM)] was about 40: 60. MF group was fed roughage consisting of 3.7% Chinese wildrye and 23.4% alfalfa hay, the forge to concentrate(F : C) ratio(DM) was 70: 30. All the cows were fed 8 weeks and body weight, dry matter intake, body condition score, fat, protein, lactose, milk yield, total solid and somatic cell count(SCC) were recorded. Quantitative real-time PCR(q RT-PCR) was used to analyze cow mammary gland samples representing two different diets. The results suggested that different diet types had significant effects on milk yield, lactose, milk fat, milk protein, dry matter intake and somatic cell count in dairy cows, and cows fed MF diet improved milk production and lactation performance clearly(P0.05). In addition, m RNA expression of genes ACC, m TOR, STAT5, CSN2, PPARγ, FABP3 and PTEN in MF group was extremely significantly higher than that in CS group(P0.05). m RNA expression of AKT1, FAS, SCD and SREBP1 c in MF group was significantly higher than that in CS group(P0.01). In summary, the milk yield and composition in mixed forage group were significantly improved than those in corn straw group.