冀北山区散栏奶牛舍夏季风机降温效果的研究

试验旨在研究冀北山区夏季奶牛舍风机的降温效果。选择结构和饲养工艺相似的两栋舍饲散栏牛舍,分析安装风机对舍内温热环境、奶牛生理指标及产奶性能的影响。结果表明,安装风机舍的昼夜均温比对照舍低1.5℃,平均风速比对照舍高0.49 m/s,可达0.66 m/s。风机开启期间安装风机舍温湿指数(THI)显著低于对照舍(P<0.05)。此外,安装风机舍的奶牛直肠温度和呼吸频率显著低于对照舍(P<0.05),且每头牛每天产奶量比对照舍显著提高了17.0%(P<0.05),但乳脂率、乳蛋白和乳糖与对照舍相比差异均不显著(P>0.05)。由此可见,冀北山区奶牛舍安装风机可改善舍内温热环境,缓解奶牛热应激,提高奶牛的产奶性能。     

冀中平原奶牛舍温热环境评价及温热参数与生理指标的相关性分析

试验旨在评价冀中平原地区四季奶牛舍的温热环境，并分析温热参数与奶牛生理指标的相关性。选择3栋不同建筑结构的奶牛舍，对各舍温湿度和奶牛的呼吸频率、直肠温度和体表温度等生理指标进行检测。结果显示，奶牛舍四季环境温湿度和温湿指数（THI）变化显著（P<0.05），其中夏季日均温最高，为28.59 ℃；冬季日均温最低，为1.55 ℃。奶牛夏季每天平均15.5 h遭受轻度热应激，6.0 h遭受中度热应激；冬季每天平均12.0 h遭受轻度冷应激。除冬季外，各季节不同牛舍的温度和THI均未表现出显著差异（P>0.05）。相比带矮墙或卷帘的棚舍，仅设顶子的棚舍夏季平均温度要高0.80~1.27 ℃，冬季低1.36~1.84 ℃。另外，夏季奶牛各项生理指标极显著高于其他季节（P<0.01），且夏季不同舍奶牛的呼吸频率和直肠温度均表现出显著差异（P<0.05），体表温度各季节差异均达显著水平（P<0.05）。从环境温湿参数与奶牛生理参数的相关性分析可看出，各项生理参数（呼吸频率、直肠温度和体表温度）与THI、环境温度均呈显著正相关（P<0.05），但与湿度未表现出显著相关性（P>0.05）。本研究可为奶牛舍环境的评价提供科学依据，并通过环境温热参数的检测推断奶牛生理状况，为应激的发生及预警提供数据。     

Evaluation of Thermal Environment of Cowshed and Correlation Analysis Between Thermal Parameter and Physiological Parameter of Dairy Cows in Central Plain of Hebei

The purpose of this study was to evaluate thermal environment of cowshed in four seasons in central plain of Hebei,and analyze the correlation between the temperature parameters and physiological indexes of dairy cows.Three dairy cow houses with different building structures were selected,the thermal parameters (ambient temperature (Ta) and relative humidity (RH)) and physiological parameters (respiratory rate,rectal temperature and body surface temperature) were detected.The results showed that the Ta,RH and index of temperature and humidity (THI) changed significantly in four seasons (P<0.05),the average daily temperature in summer was the highest (28.59 ℃),and the average daily temperature in winter was the lowest (1.55 ℃).In summer,dairy cows were suffering from mild heat stress for 15.5 h every day,and from moderate heat stress for 6.0 h.In winter,dairy cows were under mild cold stress for an average of 12.0 h per day.The Ta and THI of three cowsheds in each season had no significant differece (P>0.05),except for that in winter.Compared with the cowshed with low wall or roller blind,the average Ta in the cowshed with only roof was 0.80-1.27 ℃ higher in summer and 1.36-1.84 ℃ lower in winter.In addition,the physiological parameters of dairy cows were extremely significantly higher in summer than those in other seasons (P<0.01).The respiration frequency or rectal temperature of cows among cowsheds in summer were significantly different (P<0.05),and the seasonal difference in body surface temperature was significant (P<0.05).Correlation analysis of thermal parameters and cow physiological parameters showed that the respiratory frequency,rectal temperature and body surface temperature were positively correlated with THI and Ta (P<0.05).However,there was no significant correlation between physiological parameters and RH (P>0.05).The results provided scientific basis for environment evaluation of cows,and physiological status of dairy cows were inferred according to environmental thermal parameters,which provided data for occurrence and early warning of stress.     

采用物理降温措施对奶牛夏季产奶性能影响的研究

本研究采用物理方法对奶牛舍实施降温,以达到改善饲养环境条件,保证夏季奶牛健康,提高产奶性能的目的。试验选取10头产奶性能稳定的荷斯坦奶牛随机分成2组,每组5头,分别置于2栋牛舍内,试验组所有牛舍安装通风与喷水装置,对照组不安装。每天11点、14点、16点定时测定舍内平均温度和相对湿度。试验结果表明,试验组牛舍内温度比对照组分别降低10%、12%、9.2%,经检验差异极显著（P<0.01）,试验组舍内相对湿度比对照组高1.9%,经检验,差异不显著（P>0.05）,试验组产乳量比对照组提高4.5%,经检验差异显著（P<0.05）。试验组乳脂率降低0.33%,对照组乳脂率降低0.16%,经检验差异不显著（P>0.05）。研究结果显示,在常规饲养及管理模式基础上,采用物理降温措施,有助于夏季奶牛生产性能改善。     

卷帘舍环境参数与奶牛泌乳性能及行为的相关性分析

旨在分析卷帘舍环境参数与奶牛泌乳性能及行为的相关性。本研究选择南北纵墙安装自动卷帘的全舍饲奶牛舍,存栏约200头5～6岁经产的健康荷斯坦泌乳奶牛(3～4胎,体重(650±100) kg)。通过检测该卷帘舍一个自然年度的环境参数,研究温热参数(温、湿度和风速)、气载微生物(细菌和真菌)、粉尘(PM_2.5和PM₁₀)和有害气体(二氧化碳(CO₂)和氨气(NH₃))与泌乳性能和行为的相关性。结果表明：1)各项环境参数均表现出季节性规律。真菌(1 049.91 cfu·m^-3)和两种粉尘(PM_2.5=17.86μg·m^-3;PM₁₀=193.07μg·m^-3)含量夏季最高,细菌含量秋季最高(1.11×10⁴ cfu·m^-3),而CO₂和NH₃浓度冬季最高(1 302.85 mg·m^-3;2....     

冀北寒区秋冬季节荷斯坦奶牛产奶性能及血液常规指标的变化规律研究

试验旨在探索奶牛对气候变化较为敏感的血液常规指标,为荷斯坦奶牛低温应激研究提供相关数据支撑及科学依据,并对该地区冬季奶牛饲养管理及耐应激个体选育提供理论依据。以河北省承德市围场县某规模化奶牛场的健康荷斯坦泌乳奶牛为研究对象,连续监测了秋季（2018年10月24日至2018年10月30日）、初冬（2018年12月4日至2018年12月10日）和深冬（2018年12月25日至2018年12月31日）牛舍温湿指数（THI）,并分别采集了15头荷斯坦奶牛血液样本,测定了9种血液常规指标,同时收集了试验牛群的8项产奶性能数据,分析荷斯坦奶牛在秋冬季节产奶性能及血液常规指标的变化规律,筛选气候变化较为敏感的血液常规指标。结果显示：秋季,牛舍平均温度为8.0 ℃,平均THI为49.38,说明试验牛群在该时期处于非低温应激状态;初冬,牛舍平均温度为－6.4 ℃,平均THI达到23.56,在168 h监测期,有92 h －8≤THI < 25,76 h 25≤THI < 39,试验牛群在该时期大部分时间处于中度低温应激状态;深冬,牛舍平均温度为－7.59 ℃,平均THI达到21.86,有43 h 25≤THI < 39,117 h 8≤THI < 25,试验牛群在该时期绝大部分时间处于中度低温应激状态。随着温度下降,奶牛直肠温度、呼吸频率显著降低（P < 0.05）;冬季奶牛血中白细胞计数（WBC）、红细胞计数（RBC）、血红蛋白（HGB）、红细胞压积（HCT）、血小板总数（PLT）、血小板压积（PCT）、单核细胞数（MO）、淋巴细胞数（LY）极显著或显著升高（P < 0.01;P < 0.05）;除红细胞压积（HCT）、白细胞计数外,其他各指标在初冬与深冬间差异不显著（P > 0.05）;红细胞平均体积（MCV）在各季节间变化不显著（P > 0.05）;与秋季相比,初冬、深冬奶牛平均日产奶量（AMY）分别下降0.71和1.17 kg/d（P < 0.01）;初冬乳脂率（FP）、乳蛋白率（PP）、脂蛋比（F/P）显著或极显著下降（P < 0.05;P<0.01）,深冬时期恢复至秋季水平（P > 0.05）;乳中非脂肪固体物质率（SP）在初冬显著下降,在深冬显著上升（P < 0.05）;初冬、深冬乳中体细胞数（SCC）分别比秋季高1.84×10⁵、1.63×10⁵ 个/mL（P < 0.05）;乳糖率（LP）及酸度在各时期均无显著差异（P > 0.05）。综合以上结果,冀北寒区荷斯坦奶牛在秋季处于非应激状态,在初冬和深冬处于中度低温应激状态,且牛群的生理指标和产奶性能受气候影响较为严重;奶牛血液红细胞、白细胞、淋巴细胞和单核细胞数为受气候影响变化较为灵敏的血液常规指标。     

荷斯坦青年牛初次配种妊娠月龄对头胎和二胎产奶量和繁殖性能的影响

旨在研究母牛初次配种妊娠月龄（age at first pregnancy,AFP）对其泌乳性能和主要繁殖性能的影响。本研究以我国北方地区2个规模化奶牛场13 927头荷斯坦母牛（A牧场8 091头,B牧场5 836头）的生产数据为基础,统计了母牛AFP、头胎和二胎的产奶量、产后首次发情时间、首次配种时间和首次受孕时间,然后将母牛根据AFP的早晚（12~19月龄）分为8组,对各试验组母牛的头胎和二胎产奶量和主要繁殖性能的数据进行比较分析。结果表明：1）2个规模化奶牛场荷斯坦青年牛AFP以13和14月龄为主（总占比70.1%）;2）AFP可显著影响荷斯坦青年牛头胎和二胎的305 d产奶量（P<0.05）,其中AFP为14月龄时A牧场头胎和二胎305 d产奶量均最高,分别为15 102和15 534 kg;3）AFP可显著影响荷斯坦青年牛头胎和二胎产后首次发情时间和受孕时间（P<0.05）,AFP为14月龄时头胎产后首次发情和受孕情况最优;4）对于产后首配时间,除A牧场头胎AFP为16月龄时产后首次配种时间显著高于AFP为17月龄时（P<0.05）外,其余各组间均无显著性差异（P ≥ 0.05）,并且各组间配种时间相差≤ 5 d;5）通过对A牧场在场牛（2 703头）与淘汰牛（660头）的AFP记录数据分析发现,在场牛的AFP为14.52月龄,显著高于淘汰牛的AFP（P<0.05）。因此,在北方地区现有的生产管理水平下,14月龄可能是荷斯坦青年牛最适宜的初次配种妊娠月龄,这对我国规模化奶牛场选择荷斯坦青年牛适宜的初次配种月龄具有一定参考价值。     

过瘤胃胆碱和有机铬对围产期奶牛免疫及抗氧化功能的影响

【目的】试验通过研究饲粮中添加过瘤胃胆碱和有机铬对围产期奶牛免疫及抗氧化功能的影响,旨在为过瘤胃胆碱和有机铬在围产期奶牛饲粮中的科学应用提供理论依据。【方法】选取40头健康、经产（平均胎次1~2）的中国荷斯坦奶牛,随机分为4组（每组10头牛）：对照组（T_O）,基础饲粮;胆碱组（T_C）,基础饲粮＋30 g/d过瘤胃胆碱;有机铬组（T_A）,基础饲粮＋8 g/d蛋氨酸铬;混合组（T_CA）,基础饲粮＋30 g/d过瘤胃胆碱＋8 g/d蛋氨酸铬。试验处理从产前20 d至产后20 d,记录奶牛产后4周内日均产奶量,分别于产前第20、10天和产犊日、产后第10、20天,于晨饲前采集血样,测定血清抗氧化（谷胱甘肽过氧化物酶（GSH-Px）、过氧化氢酶（CAT）和超氧化物歧化酶（SOD））及免疫（白介素-1（IL-1）、白介素-6（IL-6）和肿瘤坏死因子（TNF-α））功能指标。【结果】与对照组相比,3个试验组奶牛产后4周内日均产奶量均显著提高（P<0.05）;产前各组奶牛血清GSH-Px、CAT含量无显著差异（P>0.05）,但试验组奶牛血清SOD含量显著降低（P<0.05）;产犊日至产后第10天,胆碱组和有机铬组奶牛血清GSH-Px、CAT和SOD含量均显著高于对照组（P<0.05）;产后第20天,胆碱组血清GSH-Px、CAT含量均显著低于高于对照组、有机铬组和混合组,而血清SOD含量却显著降低（P<0.05）;整个试验周期内,胆碱组奶牛血清IL-1含量显著低于对照组及有机铬组和混合组（P<0.05）,IL-6和TNF-α含量却显著提高（P<0.05）。【结论】综上所述,本试验条件下,饲粮中单独添加30 g/d过瘤胃胆碱或8 g/d有机铬可明显降低围产期奶牛机体氧化应激水平,提高产奶量和机体免疫力,改善奶牛健康状况,联合添加过瘤胃胆碱和有机铬与单独添加效果差异不明显。     

新疆冬季密闭高、中产奶牛牛舍碳、氮、硫排放的对比

试验旨在比较高产和中产奶牛牛舍的空气状况。试验选取高产奶牛和中产奶牛牛舍各一栋,密闭采集测定甲烷（CH_4）、氨气、硫化氢和二氧化碳4种气体的浓度。结果表明：高产奶牛牛舍中甲烷、氨气、硫化氢和二氧化碳4种气体的浓度比中产奶牛牛舍中的各气体浓度分别提高2.69%、32.51%、3.58%和66.95%。每头高产奶牛每天排放CH_4 296.15g,每产1kg标准乳排放CH_4 11.61g。每头中产奶牛每天排放CH_4 210.54g,每产1kg标准乳排放CH_4 12.08g。随着采食量增加,牛舍中甲烷、氨气、硫化氢和二氧化碳的浓度也会增加。高产奶牛每产1kg标准乳的CH_4排放量比中产奶牛低3.89%。     

产后酮病奶牛血液生化指征分析

为了比较产后一段时期内酮病奶牛与健康奶牛血液生化指标的差异,为奶牛酮病的防控及兽医临床诊治提供理论依据。本研究选取吴忠市某集约化奶牛场待产奶牛共30头进行为期3周的血液生化指标监测,根据β-羟丁酸（BHBA）的浓度将奶牛分为酮病组和对照组并进行比较研究。结果显示,酮病组与对照组在生产当天（0 d）各项检测指标未出现显著性差异;酮病组奶牛β-羟丁酸浓度在产后7 d时较对照组极显著升高（P<0.01）;天门冬氨酸氨基转移酶（AST）和总胆红素（T-bil）浓度在产后7 d和14 d时显著升高（P<0.05）;血糖（Glu）浓度在产后7 d时显著降低（P<0.05）,产后14 d时极显著降低（P<0.01）;钙（Ca）、磷（P）浓度无显著性差异,但均低于正常参考值范围,出现低血钙、低血磷症。经分析发现,本场奶牛所患酮病为Ⅱ型酮病,酮病牛高发胎次为3~6胎,产后低血钙、低血磷、低血糖现象严重,同时奶牛酮病引发了机体肝脏功能损伤,影响母牛生产性能。     

不同季节添加复合水溶性维生素对奶牛生产性能、血液生理生化和抗氧化性能的影响

本试验旨在研究复合水溶性维生素对春、夏季奶牛生产性能、血液生理生化指标和抗氧化性能的影响。采用2×2因子随机区组设计,选取胎次、体重相近的健康成年奶牛80头,随机分为4个处理,即Ⅰ、Ⅱ、Ⅲ、Ⅳ组,4组均饲喂基础日粮,Ⅲ、Ⅳ处理在春季补充复合水溶性维生素,Ⅱ、Ⅳ处理组在夏季补充复合水溶性维生素,各组添加量均为0.02%(日粮干物质为基础),预试期7 d,正式期70 d。结果表明:在春季添加复合水溶性维生素极显著提高奶牛的平均日采食量和日产奶量(P<0.01);在夏季显著提高奶牛的平均日采食量(P<0.05),极显著提高日产奶量(P<0.01);均能极显著提高乳脂率(P<0.01),极显著降低体细胞数(P<0.01);均能显著影响淋巴细胞总数(P<0.05)。在夏季补充复合水溶性维生素能极显著增加血清总抗氧化能力、总超氧化物歧化酶(P<0.01),极显著降低乳酸脱氢酶、白蛋白、总蛋白、高密度脂蛋白、低密度脂蛋白和磷酸肌酸激酶含量(P<0.01)。综上所述,复合水溶性维生素可以提高奶牛的生产性能,增强奶牛非特异性免疫,改善奶牛抗氧化性能,减少夏季热应激。     

亚临床酮病对泌乳早期奶牛繁殖性能和血液生化指标的影响

试验旨在探究围产期亚临床酮病与泌乳早期奶牛繁殖性能、卵泡发育之间的关系,并检测试验牛血液生化指标的变化。试验在黑龙江某大型集约化牛场开展,根据产后血酮水平确定亚临床酮病组（SCK）和健康组（C）奶牛共60头,根据试验牛产后50 d内发情状况,将SCK组再分为发情组（SCKE,16头）和乏情组（SCKA,14头）,C组也同样分为发情组（CE,25头）和乏情组（CA,5头）。所有试验牛在产后50 d通过直肠检查和B超检查了解子宫复旧及卵泡发育状况,记录繁殖性能数据,并进行血液生化指标分析。结果表明：与健康组发情奶牛相比,亚临床酮病发情奶牛产后首次发情日期推迟约10 d（P<0.05）;产后50 d卵泡直径差异极显著（差值约4 mm）（P<0.01）。亚临床酮病乏情奶牛子宫复旧延迟发生率显著高于健康组发情奶牛（P<0.05）;亚临床酮病奶牛血浆中胰岛素样生长因子-1（IGF-1）含量显著低于健康奶牛（P<0.05）,而泌乳量极显著提高（P<0.01）。与发情奶牛相比,乏情奶牛血浆中甘油三酯（TG）含量显著升高（P<0.05）;葡萄糖（Glu）、胰岛素（Ins）、雌二醇（E₂）、孕酮（P₄）含量显著或极显著降低（P<0.05;P<0.01）。综合以上试验结果,奶牛患亚临床酮病而导致能量代谢指标异常是引起奶牛乏情、产后卵泡发育受阻和繁殖障碍的主要因素,进而导致奶牛繁殖力下降。     

Effect of Chinese Herb Additive on Blood Biochemical Indices and Production Performance in Transition Dairy Cows

The objective of the experiment was to investigate the effect of Chinese herb additive on production performance and blood biochemical indices in transition dairy cows.Thirty six Holstein dairy cows were randomly assigned to three treatments,supplemented with 0,150 and 300 g/d Chinese herb additive,respectively.Experimental duration was 7 weeks and the first week was the preliminary period.After delivery,feed,blood and milk samples were collected once a week for the measurement of dry matter intake,blood biochemical indexes and milk components.The results showed that cows fed 150 and 300 g/d Chinese herb additive tended to increase milk production (5.1% and 10.6% respectively) compared to control group,but the difference was not significant (P<0.05).Meanwhile,the somatic cell count in milk significantly decreased (P<0.05),which decreased by 62.7% and 76.6%,respectively.Feeding Chinese herb additive had no significant effect on dry matter intake and other milk composition (P>0.05).Compared to control group,cows received Chinese herb additive significantly decreased the content of serum NEFA (P<0.05),which decreased by 29.0% and 35.1%,respectively.There was no significant difference on other indexes in serum (P>0.05).The results showed that dietary supplementation with 300 g/d Chinese herb additive had a good effect for transition dairy cows,which could significantly reduce the somatic cell count in milk and the content of NEFA in blood,and would improve the health status of dairy cows,and the postpartum production performance of dairy cows.     

中草药添加剂对围产期奶牛血液生化指标及生产性能的影响

本研究旨在研究中草药添加剂对围产期奶牛血液生化指标及生产性能的影响。试验选择36头体况、预产期和胎次相近的荷斯坦奶牛,采用完全随机试验设计,分为3组,每组12头奶牛。3组奶牛在基础日粮中分别添加0、150和300 g/d的中草药添加剂,预饲期1周,正饲期6周。奶牛产后每周采集1次饲料样、血样和奶样,测定其干物质采食量、血液生化指标及乳成分等指标。结果表明,随着中草药添加剂饲喂量的增加,围产期奶牛产后产奶量表现出一定的升高趋势,产奶量分别增加5.1%和10.6%,但与对照组相比差异不显著（P>0.05）,围产期奶牛饲喂中草药添加剂对干物质采食量没有显著影响（P>0.05）。与对照组相比,随着中草药添加剂饲喂量的增加,乳中体细胞数显著降低（P<0.05）,分别下降62.7%和76.6%,但对乳中其他常规指标没有显著的影响（P>0.05）。与对照组相比,随着中草药添加剂饲喂量的增加,奶牛血清中非酯化脂肪酸（NEFA）含量显著降低（P<0.05）,降低水平分别为29.0%和35.1%,血清中其他常规指标没有显著变化（P>0.05）。综上所述,在本试验条件下,推荐围产期奶牛中草药添加剂添加量为300 g/d,可以显著降低乳中体细胞数和血中NEFA含量,改善奶牛健康状况,提高奶牛产后生产性能。     

Effects of Supplemental Complex Water Soluble Vitamin on Production Performance,Blood Biochemical Parameters and Oxidation Resistance of Dairy Cows

The objective of the study was to investigate the effects of supplemental complex water soluble vitamins on production performance, blood biochemical parameters and oxidative resistance of dairy cows in spring and summer.The experiment was designed by 2×2 factorial randomized blocks design.Eighty healthy dairy cows with similar parity and body weight were randomly divided to four groups, with 7 days of adaptation and 70 d experimental phase.The dairy cows in group Ⅲ and Ⅳ were fed a basal diet supplemented with complex water soluble vitamins in spring.The dairy cows in group Ⅱ and Ⅳ were fed a basal diet supplemented with complex water soluble vitamins in summer.The results showed that the ADFI and daily milk yield of dairy cows receiving water soluble vitamin in spring were extremely significantly higher (P<0.01);The ADFI of dairy cows receiving water soluble vitamin was significantly higher in summer (P<0.05) and daily milk yield were extremely significantly higher (P<0.01);The butterfat rate was extremely significantly increased and SCC was extremely significantly decreased in spring and summer (P<0.01);Supplementation of water soluble vitamin was also significantly increased LYM (P<0.05).In summer, T-AOC, T-SOD were extremely significantly increased (P<0.01), and TP, CK, LDH, TP, HDL and ALB were extremely significantly decreased (P<0.01) by water soluble vitamin supplementation than that of control group.In conclusion, complex water soluble vitamins could increase the production performance and non-specific immune function, improve the oxidative resistance and relieved the heat stress of the dairy cows.     

荷斯坦牛泌乳前期体况评分及其对泌乳性能和离群寿命的影响

为了探究荷斯坦牛泌乳前期体况评分（body condition score,BCS）的影响因素及BCS对生产性能和离群寿命的影响,本研究收集江苏省某大型牛场2018年1月至2020年12月共7 811头荷斯坦牛泌乳前期BCS、生产性能测定（dairy herd improvement,DHI）结果及淘汰记录,利用多因素方差分析法在分析奶牛泌乳前期BCS变化及影响因素基础上,重点分析泌乳前期BCS及其变化对泌乳性能和离群寿命的影响,利用Cox回归对泌乳前期不同BCS的荷斯坦牛生存曲线进行绘制,并对不同BCS荷斯坦牛的淘汰原因进行卡方检验。结果表明,全群泌乳前期BCS均值为（2.95 ±0.32）。胎次、产犊季节和泌乳天数对泌乳前期BCS有极显著影响（P<0.01）,1胎牛和夏季产犊的母牛泌乳前期BCS均最高;5~30、31~60、61~100 d BCS呈显著下降。泌乳前期BCS对产奶量、乳脂率、乳蛋白率、体细胞评分等均有极显著影响（P<0.01）。产奶量和高峰奶量随BCS的增加呈极显著下降（P<0.01）。泌乳前期BCS与产奶量、高峰奶量呈极显著负相关（P<0.01）,与乳蛋白率呈极显著正相关（P<0.01）。泌乳前期BCS的变化对SCS和高峰奶量均有显著影响（P<0.05）。泌乳前期BCS对离群胎次和淘汰月龄有极显著影响（P<0.01）。生存分析表明,BCS为2.75的牛只生存概率最大。2胎和4胎母牛、冬季产犊的母牛不同BCS淘汰比例均呈极显著差异（P<0.01）;低产淘汰的牛只泌乳前期BCS淘汰分布具有极显著差异（P<0.01）。在本研究牛群中,当泌乳前期BCS为2.75时,牛只生产性能较佳且淘汰风险最低,本研究为规模化牛场荷斯坦牛泌乳前期的饲养管理提供了参考。     

Locomotion Score and Its Impacts on Production Performance and Blood Routine Indexes in Chinese Holstein

To investigate the influencing factors of locomotion score (LS) and its impacts on production performance and blood routine index in Holstein,body condition score (BCS),LS and DHI (dairy herd improvement) of 1 486 lactating cows from two dairy farms,and the blood routine indexes of 101 lactating cows from one farm in Beijing were measured.The fixed model was used to analyze the impacts of herd,parity and lactation stage on LS,and the impacts of LS and BCS on daily milk yield,somatic cell score,milk composition and blood routine indexes in dairy cows.The results showed that both parity and lactation stage had significant impacts on LS.The LS increased with the increase of parit,the LS increased by 0.71 from first lactation to fifth and above lactation.The LS of cow in lactation stage Ⅲ(100-199 d) and Ⅵ (after 350 d) were significantly higher than cow in stage Ⅱ (45-99 d)(P<0.05),and both were higher than 2.The LS had no significant impacts on daily milk yield,milk composition and somatic cell score (P>0.05).However,the milk yield of the cow with LS≥4 was the lowest,and a decrease of 2.29 kg was found compared with the cow with LS=1.Among the various blood routine indexes,LS had significant impacts on red blood cell count,hemoglobin content,mean corpuscular hemoglobin concentration and lymphocyte count (P<0.05),and had no significant impacts on white blood cell count (P>0.05).With the increase of LS,the red blood cell count,hemoglobin content,mean corpuscular hemoglobin concentration and lymphocyte count of cows decreased with different extents.There were some problems on the body immunity and hematopoiesis of cows with poor LS.In dairy farm,regular evaluation of LS could be used to find the management problems of feet and legs,which had a great significance to reduce the loss of production performance and early culling caused by hoof disease.     

中国荷斯坦牛步态评分及其对生产性能和血常规指标的影响

为探究荷斯坦牛步态评分（locomotion score,LS）影响因素及其对生产性能和血常规指标的影响,本研究收集测定了北京地区2个规模化牧场1 486头泌乳牛的体况评分（body condition score,BCS）、LS和DHI（dairy herd improvement）数据,并测定了101头泌乳牛的血常规指标。采用固定模型分析了牧场、胎次和泌乳阶段对LS的影响,以及LS和BCS等因素对日产奶量、体细胞评分、乳成分和血常规指标的影响。结果表明,试验牛的胎次和泌乳阶段均对LS有极显著影响,LS随胎次的升高而增加,从1胎至5胎及以上,LS升高了0.71分;泌乳阶段Ⅲ（100~199 d）、Ⅵ（350 d以后）的LS均显著高于阶段Ⅱ（45~99 d）（P<0.05）,且均高于2分。LS对日产奶量、乳成分和体细胞评分均无显著影响（P>0.05）,但LS≥4分的奶牛日产奶量最低,较LS=1分的奶牛日产奶量降低了2.29 kg。各项血常规指标中,LS对奶牛红细胞数、血红蛋白含量、红细胞平均血红蛋白浓度、淋巴细胞数均有显著影响（P<0.05）,而对白细胞数无显著影响（P>0.05）。随LS升高,奶牛红细胞数、淋巴细胞数、血红蛋白含量和红细胞平均血红蛋白浓度均表现出不同程度的降低。LS较差的奶牛,其机体的免疫力和造血功能会受到不同程度的影响。在规模化牧场中,定期评估牛群的LS能及时发现牛群肢蹄管理的问题,对减少因肢蹄问题引起的生产性能损失和过早淘汰等具有重要意义。     

Effect of Supplementation of Ligustrum lucidum Ait on Production Performance and Blood Biochemical Indices in Dairy Cows

The objective of the experiment was to investigate the effect of supplementation of Ligustrum lucidum Ait on production performance and blood biochemical indices in dairy cows.Forty eight mid-lactation Holstein dairy cows were randomly assigned to four groups with twelve individuals in each group.The control group was fed a TMR diet,groups N1 to N3 were fed the TMR diets supplemented with 150,300,450 g/d Ligustrum lucidum Ait,respectively.The pre-test period lasted for 1 week and the trial period lasted for 7 weeks.The results showed that compared with control group,the supplementation of 450 g/d Ligustrum lucidum Ait significantly increased 4% FCM (P<0.05),the supplementation of 150 g/d Ligustrum lucidum Ait significantly increased milk fat content (P<0.05).Dietary supplementation of Ligustrum lucidum Ait had no effects on DMI,milk yield,milk protein,total solids (TS) and somatic cell counts (SCC) (P>0.05).Compared with control group,the supplementation of Ligustrum lucidum Ait significantly decreased blood TG content (P<0.05),and had no effects on other blood biochemical indices (P>0.05).In conclusion,dietary supplementation of Ligustrum lucidum Ait could improve milk quality and yield,and the lipid metabolism of dairy cows.     

补饲女贞子对泌乳奶牛生产性能及血液生化指标的影响

试验旨在研究补饲女贞子对泌乳奶牛生产性能及血液生化指标的影响。选择48头健康的泌乳中期中国荷斯坦奶牛,随机分成4组,每个处理组12头奶牛,对照组饲喂全混合日粮(TMR),N1、N2、N3组分别在饲喂TMR日粮的基础上补饲150、300、450 g/d女贞子。预试期1周,正试期7周。结果表明,与对照组相比,补饲450 g/d女贞子可显著提高泌乳奶牛4%校正乳产量(P<0.05),补饲150 g/d女贞子可显著提高泌乳奶牛乳脂含量(P<0.05),而对泌乳奶牛干物质采食量、产奶量及乳蛋白、总固形物含量和体细胞数均无显著影响(P>0.05);与对照组相比,补饲女贞子可显著降低泌乳奶牛血液中甘油三酯含量(P<0.05),而对其他血液生化指标均无显著影响(P>0.05)。综上所述,补饲女贞子具有提高泌乳中期奶牛生产性能、改善机体脂类代谢的作用。