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1.
对湖南地区不同奶山羊牧场奶成分进行调研,比较不同牧场间的山羊奶成分差异,同时探讨山羊奶中体细胞数的变化及其对乳成分的影响,为山羊原料奶质量安全评估及制定山羊奶体细胞正常值范围提供一定的参考。采集湖南地区5 个不同奶山羊牧场共75 份奶样,采用Foss Mickro-FT120 乳成分分析仪测定山羊奶中乳脂肪率、乳蛋白率、非脂乳固体、总固体、冰点、密度,同时采用DeLaval Cell Count(DCC)体细胞仪进行体细胞计数。菌落总数和酸度参照《食品安全国家标准 生乳》(GB19301—2010)进行测定。结果表明,5 个牧场山羊奶中乳脂肪率、乳蛋白率、非脂乳固体、冰点、密度、菌落总数均达到国家《生乳》标准,酸度稍高于国家《生乳》标准;其中体细胞数、乳蛋白、非乳脂固体、总固体存在显著差异(P<0.05);乳脂率、冰点、酸度、菌落总数不存在显著性差异(P>0.05)。山羊奶体细胞数与乳蛋白率呈极显著正相关(P<0.01),相关系数为0.338;与乳脂率呈显著负相关(P<0.05),相关系数为-0.11;与乳糖含量呈显著负相关(P<0.05),相关系数为-0.57,与非乳脂固体含量呈显著正相关(P<0.05),相关系数为0.21;与总固体无显著相关关系。  相似文献   

2.
本试验旨在比较2017年内蒙古地区生鲜乳中的体细胞数与主要奶业国体细胞数标准,对比奶罐奶和散卖奶体细胞数,同时分析生鲜乳中的体细胞数与产奶量及乳成分间相关性,旨在为生鲜乳质量安全评定及控制提供参考依据。试验于2017年采集内蒙古地区9个盟市673批次生鲜乳样品,采用Foss Mickro-FT120乳成分分析仪测定生鲜乳中乳脂肪、乳蛋白、非脂乳固体、乳糖、总固体含量,同时采用丹麦Chemomete SCC-100体细胞仪进行体细胞计数。结果表明:1) 2017年内蒙古地区生鲜乳中的体细胞数为37. 7×10~4个/mL,低于欧盟(40. 0×10~4个/mL)、新西兰(40.0×10~4个/mL)、加拿大(50.0×10~4个/mL)和美国(75.0×10~4个/mL)的生鲜乳中体细胞限定值。2)家庭散养模式散卖奶中的体细胞数(55.8×10~4个/mL)显著高于规模化牧场奶罐奶中的体细胞数(37.7×10~4个/mL)(P<0.05)。3)生鲜乳中的体细胞数与产奶量呈极显著负相关(P<0.01),相关系数为-0.190;与乳脂肪含量之间无显著相关性(P>0.05);与乳蛋白、乳糖、非脂乳固体及总固体含量之间存在极显著负相关(P<0.01),相关系数分别为-0.149、-0.295、-0.283、-0.115。由此可见,内蒙古地区生鲜乳中的体细胞数管控较好,达到甚至超过了欧美主要奶业国标准。家庭式散养方式生产的生鲜乳质量安全水平低于规模化养殖方式。生鲜乳中体细胞数增高会导致产奶量下降及乳品质的改变。  相似文献   

3.
为研究河北省唐山地区生鲜乳乳脂率和乳蛋白率的变化规律,于2013—2018年的5月、11月各采集50 份生鲜乳样品,每年共采集100 份,并加以分析。结果表明,2013—2018年唐山地区生鲜乳乳脂率≥3.3%(特优级)、乳蛋白率≥3.1%(特优级)的比例呈现上升的趋势,且5月(夏季)生鲜乳的乳脂率和乳蛋白率均普遍低于11月(秋季)。2014—2018年乳脂率与2013年相比极显著升高(P<0.01),而其他年度之间差异不显著(P>0.05)。与2013年相比,2018年乳脂率平均值提高了0.58 个百分点;乳蛋白率提高了0.12 个百分点。综上,2013—2018年唐山地区生鲜乳乳脂率和乳蛋白率呈逐渐上升的趋势。  相似文献   

4.
目的]对内蒙古不同地区生鲜牛乳进行质量等级划分,并对农区与牧区、规模化牧场与散养户奶牛的单产以及乳品质进行比较。[方法]于2023年10月分别从呼和浩特市规模化奶牛养殖场、呼和浩特市散养户奶牛场、呼伦贝尔市奶牛养殖场、锡林郭勒盟奶牛养殖场采集生鲜乳样品各30批次,共120批次,并收集各奶牛场生产记录信息。测定不同地区乳样的乳成分(乳脂率、乳蛋白率、总固体含量、非脂乳固体含量、乳糖含量)、体细胞数及菌落总数;依据《生牛乳质量分级》(NY/T 4054—2021)对3个地区的生鲜乳进行质量等级划分;采用统计学方法比较农区(呼和浩特市)与牧区(呼伦贝尔市及锡林郭勒盟)、呼和浩特市规模化牧场与散养户奶牛的平均单产以及生鲜乳品质。[结果]锡林郭勒盟牛场生鲜乳的乳脂率和菌落总数(6.16%,83.10×104CFU/mL)显著(P<0.05)高于呼和浩特市(3.96%,14.05×104CFU/mL)和呼伦贝尔市(4.15%,38.94×104CFU/mL);呼伦贝尔市牛场的生鲜乳体细胞数(39.99万个/mL)显著(P<...  相似文献   

5.
本研究旨在通过对河北省不同年度、胎次奶牛与其产奶量及乳成分、高峰日、高峰奶的相关性分析得出规律,为河北奶牛平衡育种提供数据支撑。本研究收集河北省2017-2021年近5年的奶牛生产性能测定(DHI)数据,分别按胎次和年度进行横向、纵向统计和方差分析。结果显示,年度和胎次对日单产、乳脂率、体细胞数、高峰奶、高峰日、305d奶量都具有显著的影响。不同年度除对乳蛋白率的影响不显著外,均显著地影响产奶量和其他乳成分指标。胎次与高峰奶量呈正相关(P<0.01),与高峰日呈负相关(P<0.01),与日产奶量和群体305d奶量呈正相关(P<0.01),与体细胞数呈正相关(P<0.05),与乳蛋白率呈负相关(P<0.01);胎次对乳脂率、尿素氮有影响,但不显著(P>0.05)。  相似文献   

6.
旨在研究妊娠后期饲喂不同钙磷水平饲粮对产后伊犁马初乳成分、乳脂脂肪酸组成、血液钙磷及钙磷代谢激素、繁殖及生长代谢激素等生理生化指标的影响,为明确伊犁马在妊娠后期对钙磷的适宜需要量提供参考。本试验选取健康、无亲缘关系、12~13周岁、体重为(380±32)kg、胎次为4~5胎、处于第10妊娠月左右的伊犁马25匹,随机分为5组,每组5个重复。各组饲粮钙饲喂水平分别为36.00、39.00、42.00、45.00和48.00 g·d-1,磷饲喂水平分别为26.30、28.30、30.30、32.30和34.30 g·d-1。试验预试期10 d,正试期从第11天至母马分娩后第2天结束。母马分娩后12 h内采集初乳用于测定乳成分和乳脂脂肪酸含量,空腹血液用于测定Ca、P、甲状旁腺素(PTH)、降钙素(CT)、骨钙素(OC)、胎盘催乳素(PL)、垂体催乳素(PRL)、雌酮(E1)、雌二醇(E2)、血清孕酮(PROG)、甲状腺素(T4)、三碘甲状腺原氨酸(T3)、生长激素(GH)、胰岛素样生长因子-Ⅰ(IGF-1)等激素浓度。结果表明:1)饲粮钙磷水平对初乳中钙、磷、乳脂率、乳糖率均无显著影响,组间乳蛋白率、总固形物、体细胞数、乳脂中饱和脂肪酸(SFA)和不饱和脂肪酸(UFA)比例存在显著差异(P<0.05)。随着饲粮钙、磷水平的增加,乳磷浓度、乳蛋白率和UFA比例呈显著线性增加(P<0.05),总固形物呈显著二次增加(P<0.05),而乳糖率、SFA及肉豆蔻酸比例呈显著线性降低(P<0.05)。2)饲粮钙磷水平显著影响血液中OC和PROG浓度(P<0.05),随着饲粮钙磷水平的增加,血液中离子钙、CT和OC浓度呈显著的线性降低(P<0.05),而PTH和PROG水平呈显著的线性升高(P<0.05)。饲粮钙、磷水平对PL、PRL、E1、E2等生殖激素以及T3、T4、GH和IGF-1等生长代谢激素浓度均无显著影响。由此可见,在本试验条件下,饲粮钙磷通过提高初乳中乳蛋白率和总固形物来改变乳脂中饱和脂肪酸含量和不饱和脂肪酸比例影响初乳成分;通过降低血液中OC浓度影响钙磷代谢;通过提高血液中PROG浓度影响繁殖状况。  相似文献   

7.
乳脂率和乳蛋白率是决定牛奶品质的重要成分,受许多因素的影响。试验旨在研究南方高度集约化饲养条件下自然月份、产犊季节、泌乳期和胎次对乳中乳脂率和乳蛋白率的影响。采样测定478头南方荷斯坦奶牛一个自然年度(2007年4—2008年3月)的主要乳成分和体细胞数(SCC),采用最小二乘法,分析自然月份、产犊季节、泌乳期和胎次对乳脂率和乳蛋白率的影响。结果表明:自然月份、泌乳期和胎次对乳脂率的影响极显著(P0.01),产犊季节对乳脂率的影响显著(P0.05);自然月份、产犊季节、泌乳期和胎次对乳蛋白率的影响极显著(P0.01);乳脂率与体细胞数呈极显著负相关(P0.01),而乳蛋白率与体细胞数呈极显著正相关(P0.01);乳脂率和乳蛋白率与日产奶量呈极显著负相关(P0.01)。结果提示在实际生产中,可以通过对影响乳成分因素的调控提高牛奶质量。  相似文献   

8.
目的 生鲜乳的冷却是牛奶安全生产的重要环节,比较不同制冷模式对生鲜乳品质的影响非常重要。方法 本项目对比了速冷和直冷两种生鲜乳制冷模式对生鲜乳冷却时间、温度、酸度、菌落总数的影响,以期为更好地利用和推广生鲜乳速冷技术提供参考。结果 速冷模式可以在1~3 min内将生鲜乳温度冷却至4 ℃,效率远高于常规直冷模式,综合经济效益显著;在奶罐温度保持上,在4 h内速冷模式下,生鲜乳温度(5.12 ℃)、酸度(13.47 OT)、菌落总数(1.58 CFU/mL)极显著优于直冷模式的温度(5.55 ℃)、酸度(12.92 OT)、菌落总数(4.06 CFU/mL);对温度、酸度、菌落总数双变量相关分析结果表明,在直冷模式下,温度与酸度、菌落总数相关性不显著;在速冷模式下,温度与酸度呈显著的负相关性,与菌落总数无显著相关性。结论 采用速冷模式可有效降低菌落总数,减少微生物繁殖,保障生鲜乳的质量,综合效益显著,为传统牧场奶厅改造,保障优质乳生产提供了可行性方案。  相似文献   

9.
本研究旨在探析我国规模奶牛场奶牛个体乳蛋白的水平、分布和影响因素。利用SAS9.0的GLM过程,统计分析覆盖16省(市、区),33个规模奶牛场,23351头中国荷斯坦牛,从2007年至2009年连续3年的237430个奶牛个体生鲜乳的乳蛋白率检测记录。分析表明,我国规模奶牛场奶牛个体生鲜乳的乳蛋白率平均3.28±0.22%。其中,乳蛋白率大于等于2.95%的奶牛个体占80.2%,所提供乳蛋白量占群体混合样生鲜乳总蛋白量的79.3%。奶牛的胎次、产奶阶段、产奶量、乳脂率、体细胞数、泌乳季节、泌乳月份都极显著影响奶牛个体生鲜乳的乳蛋白率(P〈0.01);饲养区域、奶牛场和年度总体显著影响奶牛个体生鲜乳的乳蛋白率(P〈0.05)。我国规模奶牛场奶牛个体生鲜乳的乳蛋白率主要处于2.95%以上(〉80%),合理调控各种影响因素,可有效提高生鲜乳的乳蛋白率。  相似文献   

10.
【目的】 通过对独龙牛(Bos frontalis)和云岭牛初乳成分测定,揭示两牛种初乳成分的差异性。【方法】 采集独龙牛和云岭牛(年龄、胎次和饲养管理基本一致)分娩第1天初乳样品共45份,测定其乳蛋白、乳脂肪、乳糖、总固形物(TS)、非脂固形物(SNF)和乳尿素氮(MUN)含量及体细胞数(SCC)和冰点(FP),采用独立样本t检验比较独龙牛和云岭牛初乳成分差异。【结果】 独龙牛初乳中乳蛋白、乳脂肪、TS、SNF含量分别为16.77%、4.70%、27.82%和22.39%,比云岭牛的分别高28.11%(P<0.01)、5.38%(P>0.05)、22.45%(P<0.01)和26.93%(P<0.01);乳糖、MUN含量和SCC分别为2.98%、354.2 mg/L和35.73×104/mL,比云岭牛的分别低10.38%(P<0.05)、39.63%(P<0.01)和78.60%(P<0.01);FP为-0.5337 ℃,比云岭牛的高0.1383 ℃(P<0.01);乳脂蛋白比(FPR)为0.266,比云岭牛的低0.131(P>0.05)。【结论】 独龙牛和云岭牛分娩第1天的初乳成分存在较大差异,独龙牛初乳营养价值较高。  相似文献   

11.
The purpose of the study was to estimate the extent to which one quarter could be inflamed relative to the other three quarters of a cow, given that knowledge only of the composite milk somatic cell count (SCC) was available. An algebraic relationship, which incorporated the parameters of composite milk SCC, production loss associated with composite milk SSC, SCC of milk from an inflamed quarter, and SCC from three non-inflamed quarters, was used to derive hypothetical estimates of the SCC in one inflamed quarter. A simple case was considered in which one quarter was mastitic, the SCC in milk of the noninflamed quarters was equal, and there was no production compensation by the noninflamed quarters. Previously published estimates were used for production loss associated with composite milk SCC. For moderate composite milk SCC (300,000-500,000 cells/mL) and low-to-moderate SCC in milk of noninflamed quarters (100,000 cells/mL), the SCC of milk from one inflamed quarter was predicted to be very high, ranging from about 1.26 million (log10 SCC = 6.1) to 6.3 million (log10 SCC = 6.8) cells/mL, and compatible with signs of clinical mastitis. These results suggest that in order to screen cows with clinical mastitis in only one quarter, composite milk SCC should be considerably lower than values presented previously by other investigators.  相似文献   

12.
Quarter Milking for Improved Detection of Increased SCC   总被引:1,自引:0,他引:1  
The aim of the present study was to investigate whether milk composition and milk yield are changed in relation to a moderate increase in milk somatic cell count (SCC) in separate udder quarters. During a period of 13 weeks, 4158 bulk quarter milk samples from 68 cows were collected and analysed for milk SCC and milk composition. The sampling was done twice weekly. The cows were in different stages of lactation and in different lactation numbers. For calculations, three groups of cows were formed according to their SCC value. Group 1 cows, where all quarters had an SCC <100,000 cells/ml at all sampling occasions, were considered to be non-affected. Group 2 cows had one udder quarter with an increased SCC >100,000 cells/ml and 1.5-fold higher than the opposite quarter at one sampling occasion. For group 3 cows, the increase in SCC remained for several consecutive sampling occasions. Data from group 1 cows revealed that front and rear quarters were similar when compared with each other. For group 3 cows, the lactose content in milk decreased significantly, simultaneously with the increase in SCC and remained decreased for two sampling occasions after the initial increase in SCC. It was concluded that deviations in lactose content within front and rear quarters, respectively, may be a useful tool for detection of moderately increased SCC in separate udder quarters.  相似文献   

13.
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.  相似文献   

14.
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。  相似文献   

15.
This study was conducted to investigate the normal somatic cell count (SCC) and to define subclinical mastitis in Murrah buffaloes. Data were collected from 60 clinically normal buffaloes stationed at five farms of Chitwan Nepal and Buffalo Research Center, Hissar, India. Somatic cell count was measured using the Newman-Lampert staining technique. The upper limit of SCC was determined >or=200 000/ml of milk based on the mean +/- 2SD of a total SCC. Abnormal data of the SCC was repeatedly removed, which lie beyond the values of more than mean + 2SD until all the data come to lie within (mean + 2SD). Averages of SCC of right front and right hind quarters were significantly higher than left front and left hind quarters. Nearly 94% of California mastitis test (CMT) negative quarters were having somatic cells >or=200 000/ml. The mean SCC of CMT positive quarter was significantly higher (P < 0.01) than CMT negative quarters. Subclinical mastitis was diagnosed on the basis of samples with SCCs >or=200 000/ml with positive bacterial cultures. Subclinical mastitis was found in 21.7% buffaloes and 8% of the quarter foremilk samples. Neutrophil counts were significantly higher in subclinical mastitis milk.  相似文献   

16.
本试验旨在通过对不同来源生鲜乳的相关指标进行测定和比较分析,评价其品质,为地方奶牛养殖业的发展提供参考依据.采集2017-2020年云南省养殖专业合作社、乳品公司养殖场、收购站和机械化挤奶站4种来源的生鲜乳共661个样品,采用国家标准方法测定其相关指标,用SPSS 22.0统计软件做单因素方差分析.结果显示,2017-...  相似文献   

17.
本研究采用DHI检测方法对云南高原饲养的萨能奶山羊进行体细胞数统计和相关分析,探讨奶山羊体细胞数对羊奶主要成分及含量的影响。结果表明,萨能奶山羊乳体细胞数与乳脂率呈正相关(P=0.141),与乳蛋白率呈极显著正相关(P<0.01),与乳糖含量呈极显著负相关(P<0.01),与总固形物含量呈显著正相关(P<0.05),与尿素氮含量呈极显著负相关(P<0.01)。乳汁体细胞数的增加对羊乳的品质产生很大影响,造成羊乳蛋白、脂肪含量和总固形物含量上升;乳糖和非蛋白氮含量降低。从多种因素考虑,6月份所测得的体细胞数和乳成分含量可作为萨能奶山羊乳品质质量标准的参考。  相似文献   

18.
本研究旨在探讨瘤胃发酵产物乙酸、丙酸以及乙酸和丙酸比对奶牛干物质摄入量(DMI)、产奶量(MY)和乳成分的影响。通过回顾已发表文献,使用荟萃分析的方法构建模型并进行相应的回归分析和相关性分析。试验整理了关于奶牛生产性能的中文及英文相关文献51篇,共计181个处理,研究不同的饲料原料、营养成分、饲料添加剂对不同生理阶段泌乳奶牛瘤胃发酵指标及生产性能的影响。基于此51项试验的荟萃分析结果表明,与瘤胃内乙酸和丙酸产量相比,奶牛的产奶量(R2=-0.426,P<0.01)、乳脂率(R2=0.359,P<0.01)、乳脂产量(R2=-0.257,P<0.01)、挥发性脂肪酸(VFA)(R2=-0.226,P<0.05)和干物质采食量(DMI)(R2=-0.485,P<0.01)与瘤胃发酵产物乙酸和丙酸比有更强的相关性;瘤胃乙酸和丙酸比与奶牛的产奶量、乳脂率、乳脂产量和DMI存在极显著的一元线性回归关系(P<0.01),其比值的增加会导致DMI、产奶量、乳脂产量极显著降低(P<0.01),乳脂率极显著升高(P<0.01),瘤胃乙酸和丙酸的比值每增加1,乳脂率增加0.26%,奶牛的干物质摄入量、产奶量分别减少2.34和4.99 kg。通过荟萃分析发现,乙酸与丙酸的比值可以更科学地预测乳脂在乳中的占比且准确反应牛奶乳脂率的变化,为饲粮的选取及调控乳品质提供了参考价值。  相似文献   

19.
The purpose of this experiment was to study the effect of gender on the slaughter performance and meat quality of Sunite sheep.Twelve 6-month-old Sunite rams and ewes at the same body condition were selected from the grazing herds of the Sunite Zuoqi Improvement Station Breeding Farm to determine their slaughter performance and meat quality.The slaughter test results showed that the bone quality and bone-meat ratio of the rams were significantly higher than that of the ewes (P<0.05),and the net meat quality and net meat rate of the ewes were significantly higher than that of the rams (P<0.05).The results of meat quality traits showed that the drip loss of ewes were significantly lower than that of rams (P<0.05),and the other indicators were not significantly different (P>0.05).The results of conventional nutrient composition of muscles showed that the intramuscular moisture content of the rams were significantly higher than that of the ewes (P<0.05),and the intramuscular fat content of the ewes were significantly higher than that of the rams (P<0.05),while the other indicators were not significantly different (P>0.05).The results of amino acid determination showed that the essential amino acid ratio in muscle of sunite ewes were significantly higher than that of rams (P<0.05),but there was no significant difference between the rams and ewes that formed the precursor amino acid content of meat flavor (P>0.05).Fatty acid measurement results showed that the saturated fatty acid ratio in the subcutaneous fat of rams was significantly lower than that of ewes (P<0.05).There was no significant difference in the ratio of saturated fatty acids in muscle fat and tail fat (P>0.05);The ratio of monounsaturated fatty acids in ewes tail fat was significantly higher than that of rams (P<0.05).The ratio of monounsaturated fatty acids in subcutaneous fat and intermuscular fat was not significantly different between rams and ewes (P>0.05).The ratio of polyunsaturated fatty acids in intermuscular fat of rams was significantly higher than that of ewes (P<0.05),and there was no significant difference in the content of polyunsaturated fatty acids in subcutaneous fat and tail fat (P>0.05).In summary,it showed that gender had a certain influence on the slaughter performance and meat quality of 6-month-old Sunite sheep.  相似文献   

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