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1.
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   

2.

Background

Milk produced by cows in receipt of antimicrobial therapy may contain antimicrobial residues. Such antimicrobial-containing waste milk must be withdrawn from human consumption and is therefore sometimes used as calf feed. Unfortunately, this approach might promote selection of antimicrobial resistant bacteria in the calves’ intestinal microbiota. The objectives of this study were therefore to obtain an overview of waste milk feeding practices on Swedish dairy farms and to investigate if these practices were associated with certain farm characteristics. A representative group of 457 Swedish dairy farmers participated in a web-based survey with questions about the use of colostrum and milk from cows treated with antimicrobials at dry off or during lactation, respectively, as calf feed.

Results

Colostrum (milk from the first milking after calving) and transition milk (milk from the second milking to the fourth day after calving) from cows treated with antimicrobials at dry off was fed to calves on 89% and 85% of the farms in the study, respectively. When antimicrobial therapy was given to cows during lactation, 56% of the farms fed milk that was produced during the course of treatment to calves, whereas milk that was produced during the subsequent withdrawal period was fed to calves on 79% of the farms. Surveyed farmers were less prone to feed such milk if the antimicrobial therapy was due to mastitis than other infections. In Sweden, a majority of antimicrobial treatments during lactation are systemic administration of benzylpenicillin and thus, the bulk of waste milk in Sweden is likely to contain residues of this drug. Feeding waste milk to calves was more common on non-organic farms, and on farms located in Southern Sweden, and was less common on farms with cows housed in cold free stalls barns.

Conclusions

Waste milk that may contain antimicrobial residues is, at least occasionally, used as feed for calves on a majority of surveyed Swedish dairy farms. Future work should focus on the effect of waste milk feeding on the occurrence of antimicrobial resistant bacteria in the calves’ intestinal microbiota.  相似文献   

3.
This study investigated the effects of substituting ear corn silage (ECS) for commercial formula feed on milk production and milk fatty acid profiles in grazing dairy farms during the summer season. A field survey was conducted on five grazing dairy farms in every summer month of 2017, 2018, and 2019. Three of the five farms substituted fresh ECS for the commercial formula feed at a ratio of 2:1 from July of each year (ECS farms). Other farms maintained the same feeding management as before (non‐ECS farms). An interview survey was conducted on each farm to calculate feed intake and milk yield per cow. Feed and milk samples were collected in each survey. Milk compositions and milk fatty acid profiles were determined. The substitution of ECS for the commercial formula feed did not affect milk yield or milk composition, but ECS farms maintained low levels of milk urea compared with non‐ECS farms (p < .01). The ECS substitution also influenced some of the milk fatty acid proportions; C16:0 and C16:1 increased, and trans‐11 C18:1, cis‐9,trans‐11 C18:2, and the sum of polyunsaturated fatty acids decreased, while these fatty acid proportions were maintained in non‐ECS farms throughout the summer season (p < .05).  相似文献   

4.
Research has shown that total bacterial count (TBC), which is the bacterial growth per ml of milk over a fixed period of time, can be decreased by good hygiene and farm management practices. The objective of the current study was to quantify the associations between herd management factors and bulk tank TBC in Irish spring calving, grass-based dairy herds. The relationship between bulk tank TBC and farm management and infrastructure was examined using data from 400 randomly selected Irish dairy farms where the basal diet was grazed grass. Herd management factors associated with bulk tank TBC were identified using linear models with herd annual total bacterial score (i.e., arithmetic mean of the natural logarithm of bulk tank TBC) included as the dependent variable. All herd management factors were individually analysed in a separate regression model, that included an adjustment for geographical location of the farm. A multiple stepwise regression model was subsequently developed. Median bulk tank TBC for the sample herds was 18,483 cells/ml ranging from 10,441 to 130,458 cells/ml. Results from the multivariate analysis indicated that the following management practices were associated with low TBC; use of heated water in the milking parlour; participation in a milk recording scheme; and tail clipping of cows at a frequency greater than once per year. Increased level of hygiene of the parlour and cubicles were also associated with lower TBC. Herd management factors associated with bulk tank TBC in Irish grazing herds were generally in agreement with most previous studies from confinement systems of milk production.  相似文献   

5.
本研究旨在探析我国规模奶牛场奶牛个体生鲜乳体细胞数（SCC）的水平、分布和影响因素。利用SAS9.0的GLM模型,统计分析覆盖16个省（市、区）,33个规模奶牛场,23 351头中国荷斯坦牛,从2007年至2009年连续3年的225 775条奶牛个体生鲜乳SCC检测记录。结果表明：奶牛个体生鲜乳SCC的总体均值为48×104cell/mL,标准差为117×104cell/mL,个体生鲜乳SCC波动范围较大;其中,77.9%的奶牛个体,其生鲜乳SCC小于50×104cell/mL,对群体混合样生鲜乳SCC的影响系数为0.26;11.3%的奶牛个体,其生鲜乳SCC介于50×104～100×104cell/mL之间,乳房处于隐性感染状态,对群体混合样生鲜乳SCC的影响系数为0.16;10.8%的奶牛个体,生鲜乳SCC大于100×104cell/mL,理论上乳房处于临床感染状态,对群体混合样生鲜乳SCC的影响系数为0.58。奶牛个体生鲜乳体细胞数评分（SCS）呈正态分布,与奶牛个体因素（产奶量、乳脂率、乳蛋白含量、胎次和泌乳阶段）和环境因素（泌乳月份、泌乳季节）差异极显著（P〈0.01）,与奶牛养殖区域、奶牛场差异不显著（P〉0.05）。我国规模奶牛场奶牛个体生鲜乳SCC主要在50×104cell/mL以下,依据影响参数能实现对生鲜乳SCC水平的调控。  相似文献   

6.
In order to determine the safety of milk produced by smallholder dairy goat farms, a farm-based research study was conducted on commercial dairy goat farms to compare the microbiological quality of milk produced using 3 different types of dairy goat production systems (intensive, semi-intensive and extensive). A survey of dairy goat farms in and around Pretoria carried out by means of a questionnaire revealed that most of the smallholder dairy goat farms surveyed used an extensive type of production system. The method of milking varied with the type of production system, i.e. machine milking; bucket system machine milking and hand-milking, respectively. Udder half milk samples (n=270) were analysed, of which 31.1% were infected with bacteria. The lowest intra-mammary infection was found amongst goats in the herd under the extensive system (13.3%), compared with 43.3% and 36.7% infection rates under the intensive and semi-intensive production systems, respectively. Staphylococcus intermedius (coagulase positive), Staphylococcus epidermidis and Staphylococcus simulans (both coagulase negative), were the most common cause of intramammary infection with a prevalence of 85.7% of the infected udder halves. The remaining 14.3% of the infection was due to Staphylococcus aureus. Bacteriology of bulk milk samples on the other hand, showed that raw milk obtained by the bucket system milking machine had the lowest total bacterial count (16,450 colony forming units (CFU)/ml) compared to that by pipeline milking machine (36,300 CFU/ml) or hand-milking (48,000 CFU/ml). No significant relationship was found between the somatic cell counts (SCC) and presence of bacterial infection in goat milk In comparison with the herds under the other 2 production systems, it was shown that dairy goat farming under the extensive production system, where hand-milking was used, can be adequate for the production of safe raw goat milk.  相似文献   

7.
This study intends to clarify the effects of hands‐on dairy farming experience on the consumption of milk and dairy products. A survey was conducted on 474 elementary schoolchildren and their parents at eight elementary schools that offered hands‐on dairy farming experience at four dairy farms in Hokkaido, Japan. In the survey, questionnaires were used to inquire about the children's milk and dairy product intake before and after the hands‐on experience. In addition, milk intake at school was investigated weekly for 3 months after the hands‐on experience. The parents were asked about the children's intake of milk and dairy products at home before and after the hands‐on experience. Analysis of the survey results indicated a significant increase in the amount and frequency of milk consumed and the frequency of yogurt consumed at home by the children immediately after the hands‐on experience. Accordingly, the study suggested that the hands‐on dairy farming experience had the effect of increasing children's milk and dairy product consumption at home.  相似文献   

8.
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   

9.
A study was conducted to estimate the record keeping, genetic selection, educational, and farm management effects on average milk yield per cow (AYC), milk fat percentage, bacterial score, and bulk tank somatic cell count (BTSCC) of dairy farms in the central region of Thailand. Farms were located in the provinces of Saraburi and Nakhon Ratchisima and were members of the Muaklek dairy cooperative. Records from individual animals were unavailable. Thus, farm records of milk yield, milk fat percentage, bacterial score, and BTCCC were collected from July 1, 2003 through June 30, 2006. Additional record keeping, genetic selection, education, and farm management information was collected through a questionnaire in May of 2006. Data from the Muaklek dairy cooperative and the questionnaire were then merged by a farm identification number. A single trait mixed model was used to analyze AYC, milk fat percentage, and BTSCC, while a log linear model was used to analyze bacterial score. Results showed that farms that kept records on individual animals had higher (P < 0.05) milk fat percentages and lower bacterial scores than farms that did not. Farms that used genetic information (EBV) and phenotypes when selecting sires were higher (P < 0.05) for milk fat percentage than farms that used only phenotypes and personal opinion. Farms milking cows with a single unit milking machine and by hand, had higher (P < 0.05) bacterial scores and BTSCC than farms using only a single or multi unit machine. Overall farms that kept individual animal records, used EBV when selecting sires, used a single method for collecting milk, and used family labor achieved higher performance from their herds than farms that did not.  相似文献   

10.
An observational study was conducted in Wisconsin to compare production and management on organic and conventional dairy farms. Thirty organic dairy herds, where antimicrobials are rarely used for calves and never used for cows, were compared with 30 neighboring conventional dairy farms on which antimicrobials were routinely used for animals of all ages. A seven-page questionnaire regarding milk production, milking practices, housing, incidence of the major dairy diseases and medical treatments was used to assess management and production during 2000-2001. Body condition scores (BCS) of lactating cows and environmental and animal sanitation scores (EASS) were also collected on each of two occasions. The organic herds had significantly fewer cattle than did the conventional herds (P=0.017). The average daily milk production per cow in organic dairy herds (20.2 kg/day) was lower than that of conventional herds (23.7 kg/day). The incidence of clinical mastitis (CM) on organic farms (28 cases per 100 cow-years at risk) was not statistically different from that of on conventional farms (32 cases per 100 cow-years at risk). No significant difference in bulk tank somatic cell count (BTSCC) was observed between organic farms (262,000 cells/ml) and conventional farms (285,000 cells/ml). The average annual cull rate was 18.0 cases per 100 cow-years for the conventional farms and 17.2 for the organic farms (P=0.426). Our paired t-test results indicated significantly higher parasite burden on organic dairy farms; however, no significant difference between the two farm types when controlling for season (March and September), grazing intensity (no grazing, little grazing, grazing with access to housing and grazing only) and herd average milk production per cow. There was little evidence of other fundamental differences between the two farm types in other management and production parameters.  相似文献   

11.
In 57 Holstein cows where the dairy farm uses a milking parlor system, the somatic cell count (SCC) increased persistently in the bulk milk (monthly mean 52.3 x 10(4) cells/ml; range 21 to 94 x 10(4) cells/ml). We detected S. aureus in 24 (41.2%) of the 54 lactating cows and in 29 (12.8%) of 227 quarters of the 57 milking cows in the herd. A control program was implemented in an effort to eradicate S. aureus mastitis from this dairy farm. The control plan established improved handling of the lactating cows, improved milking procedures, dry-cow therapy, and culling of infected cows. The program was monitored for 3.5 years by frequent checkups on the rate of S. aureus infection, the SCC, and the changes in milk composition. Eighteen months after the control program was started, the rate of S. aureus infection in the quarter milk decreased dramatically, and no S. aureus isolates were found in the milk of the remaining cows. The SCC in the bulk milk of the herd dropped to a monthly mean of <20 x 10(4) cells/ml. In conclusion, the control program was effective for controlling persistent S. aureus mastitis in this dairy herd.  相似文献   

12.
The objective of the study was to investigate the influence of dairy cow management techniques and milking methods on hygienic quality of raw milk. Total Bacterial Count (TBC) and Total Coliform Colonies (TCC) were studied to determine the effects. Investigations were carried out in fifty dairy farms from August 2007 to December 2007. The mean TBC and TCC for the herds with comparatively good and poor management practices were 0.9 × 105 cfu/ml and 0.2 × 103/ml and 99 × 105 cfu/ml and >180 × 103/ml, respectively. The overall mean TBC (22 × 105 cfu/ml) and TCC (47 × 103/ml) obtained in this study exceeded the internationally recommended levels for TBC (105 cfu/ml) and TCC (<1,000/ml). The overall results obtained suggested that the raw milk tested was of poor hygienic quality with the presence of a great variability among milk samples.  相似文献   

13.
试验采用随机分组试验设计,选择规模化养殖模式、园区式奶农合作组织养殖模式下的2个奶牛场,每个奶牛场选择80头健康的泌乳奶牛,按照产奶胎次、体重、泌乳阶段和产奶量相近原则随机分为2组,每组40头,就试验组饲粮中添加25g/(头·d)过瘤胃赖氨酸(RPLys)对奶牛产乳量及乳成分的影响进行研究。试验结果发现,经过饲喂之后,试验组与对照组相比,产奶量有显著提高(P<0.05)。两种模式下乳蛋白和乳脂肪含量均有提高趋势,但是试验组与对照组没有显著差异(P>0.05)。乳糖、非脂乳固体两个指标略有提高,但差异不显著(P>0.05)。规模化和园区式的试验组相对于对照组每天每头奶牛的净增利润分别为1.80元和0.52元。  相似文献   

14.
In many developing countries, milk production varies greatly according to farm size, cattle breed, and milking practices. However, production systems often are dominated by smallholder farms. Therefore, relatively small volumes of milk are delivered daily from numerous farms to intermediate cooperatives which supply industrial units. This paper argues that in such two-stage dairy chains, milk quality could be improved by focusing on farming practices rather than on the testing of individual deliveries. Indeed, it is difficult to analyze their quality due to technical, economic, and logistic limitations. The objective of this study is to link on-farm practices with milk chemical quality parameters (fat and protein) and hygienic quality criteria (Aerobic Plate Count, APC and Coliforms). Cattle management practices were monitored monthly over one year on 23 farms located on an irrigation scheme in Morocco. 276 milk samples were analyzed. The monthly variability of milk quality parameters was then characterized. Results show that average cow milk chemical parameters vary within a normal range. They remain primarily linked to the genetic type of cows, the lactation stage, and the conversion of feed concentrates’ net energy into milk. Overall milk hygienic quality was poor (APC and Coliforms counts were 100 fold international norms), due essentially to a lack of hygiene and inadequate milking conditions (hands, udder, and teat washing, type of bucket used, dirtiness of cows...). It is suggested that a close monitoring of herd management practices may allow the indirect control of milk quality parameters, thereby avoiding costly analyses of numerous smallholder milk deliveries.  相似文献   

15.
本次调研共收集了华北地区99家奶牛场的用水及粪污处理情况数据进行了分析总结。结果表明,①85.9%的牛场以深井水作为水源,其中61.2%的牛场对用水进行消毒处理,43.5%的牛场安装有水表并记录用水情况。②在牛场用水中,牛的饮水量所占比例最高,达60%以上;其次为挤奶厅用水,约占20%。③夏季牛场头均饮水量、挤奶厅用水量、喷淋用水量均显著高于春秋冬季(P<0.05),夏季的头均总用水量比春秋冬季增加了33%(P<0.01)。随着牛场存栏量的增大,奶牛头均总用水量显著减少(P<0.05)。④年产奶量较高的牛场每产1kg牛奶饮水量、挤奶厅用水量显著降低(P<0.01),致使每千克产奶量的总用水量减少52%(P<0.01),用水效率提高。⑤随着养殖规模的增大,牛场雨污分离设施与干湿分离设施配备率分别显著增至62%、72%(P<0.05,P<0.01)。由此可得,存栏量越大、年产奶量越高,牛场每产1kg牛奶用水量越低,用水效率越高,而且配备的雨污分离设施、干湿分离设施比例越高,这些均有利于减少单位产奶量的粪污产生量及其处理压力。  相似文献   

16.
为调查我国当前主流饲喂方式下奶牛静脉血内毒素浓度的范围及内毒素浓度与产奶量的相关性,本试验首先验证了应用鲎试剂法定量奶牛静脉血中内毒素浓度的可行性,在此基础上,分别检测了安徽牧场 １（６０头,饲粮精粗比 ４５∶５５）、江苏牧场（１５头,按产奶量高低精粗比分别为 ２０∶８０、４５∶５５、５０∶５０）和安徽牧场 ２（１４头,饲粮精粗比 ７０∶３０）共 ８９头奶牛的尾静脉血中内毒素浓度,并进行了内毒素浓度与产奶量的相关性分析。结果表明：鲎试剂法可有效检测奶牛静脉血中内毒素浓度,３个牧场奶牛静脉血中内毒素浓度高低不等,在 ０～１．５０ＥＵ／ｍＬ范围内。奶牛静脉血中内毒素浓度与产奶量之间的相关性皆不显著（Ｐ＞０．０５）,但安徽牧场 ２的相关系数（０．１９５２）大于安徽牧场 １（０．０２０５）和江苏牧场（０．０３７６）。结果提示,鲎试剂法可用于定量检测奶牛血中内毒素浓度,在我国当前的饲喂方式下,奶牛血液中普遍含有内毒素,静脉血内毒素浓度与产奶量无显著相关性。  相似文献   

17.
乳汁体细胞数(somatic cell count,SCC)是检查奶牛乳房炎和牛奶质量的指标,为了解南宁某规模化奶牛场奶水牛SCC情况及SCC与其他乳成分的关系,试验随机选取该场152份泌乳早期乳样,测定其SCC、乳汁比重、蛋白质、脂肪、总固形物、非脂固形物及乳糖的含量,并对其进行相关性分析。结果表明,SCC小于50万/mL的乳样占被检奶样总数的88.16%,大于100万/mL的占1.97%;乳汁比重、乳蛋白、乳糖和非脂固形物含量均随着SCC的升高而下降,而乳脂含量随着SCC的升高而呈上升趋势;SCC与乳糖及非脂固形物含量呈极显著负相关(P<0.01)。因此,奶水牛乳中SCC不仅与乳糖和非脂固形物含量密切相关,也提示其与奶水牛产后营养代谢状况有关。  相似文献   

18.
In developing countries, milk quality is often mismanaged in relation to husbandry practices, collection logistics, and the production of small batches. This paper investigates how the management of milk quality from farm to dairy processor impacts on both chemical and hygienic indicators, in a context characterized by farm scale diversity, the co-existence of formal and informal markets, and high milk demand. It is based on an analysis of the chemical and hygienic quality of milk samples collected over a 12-month period from 20 farms and three dairy processors. Data from the farmers’ husbandry practices and the logistics of milk collection were also collected. A large range of quality profiles and farming practices were observed. This diversity is explained by rainfall and temperature pattern, farm size which affects hygienic quality, and lack of efficient logistics between farms and dairy processors. The findings indicate that in a context of high demand for milk and poor private and public regulations, milk quality is impacted upon by poor stakeholders’ management practices.  相似文献   

19.
旨在研究乳房炎及病原菌组成对中国荷斯坦牛测定日泌乳性能及体细胞数变化的影响.本研究于2009年9月对江苏某奶牛场140头成年中国荷斯坦泌乳牛进行乳房炎检测和DHI测定,同时对隐性乳房炎阳性乳区进行病原菌分离鉴定,并分析了不同乳房炎类型和隐性乳房炎病原菌组成对测定日泌乳性能和乳中SCC变化的影响.结果表明,该牛场临床乳房炎、隐性乳房炎和正常奶牛比例分别为10.00％、51.10％和37.90％,其中隐性乳房炎以大肠杆菌和链球菌混合感染最多(19头,占26.00％),其次为链球菌单独感染(17头,占23.30％).由1种细菌单独感染的比例为26头(占36.11％),2种或2种以上细菌混合感染为44头(占61.11％).乳房炎类型对测定日产奶量、乳糖含量、体细胞数和体细胞评分4个指标影响达到极显著水平(P＜0.01),临床乳房炎和隐性乳房炎奶牛日产奶量和乳糖含量极显著低于正常奶,同时体细胞数和体细胞评分极显著高于正常奶,而临床乳房炎奶和隐性乳房炎奶在所有检测指标上均无显著差异,但临床乳房炎奶比隐性乳房炎奶体细胞数高出约100万·mL-1.不同病原菌组成类型对乳中体细胞数和体细胞评分有极显著影响(P＜0.01),而对其它性状无显著影响(P＞0.05).混合感染奶牛测定日产奶量极显著低于单独感染奶牛(P＜0.01),同时乳中体细胞数显著高于单独感染奶牛(P＜0.01).乳房炎类型对乳中SCC的变化趋势有显著影响(P＜0.01),正常奶牛维持较低SCC的能力较强,隐性乳房炎奶牛在下一泌乳月体细胞增加的可能性较大.不同隐性乳房炎病原菌组成类型对乳中SCC的变化无显著影响.奶牛生产中隐性乳房炎发病率高,危害性也最大,不同病原菌混合感染引起的隐性乳房炎对测定日产奶量和乳中体细胞数影响最大.该结果为奶牛场采取合理措施,降低隐性乳房炎发生率提供了参考.  相似文献   

20.
Fratini  F.  Nuvoloni  R.  Ebani  V. V.  Faedda  L.  Bertelloni  F.  Fiorenza  G.  Cerri  D. 《Veterinary research communications》2010,34(1):171-174

Selling raw milk by automatic dispenser on the farm is a good way to increase income. The aim of the present research is to evaluate both the biosecurity of dairy farms in the Pisa province and the hygienic quality of raw milk. Two farms, chosen because of previously analyzed results carried out on animals and milk, were monitored for 9 months according to the regional law DGR 381/2007. The results obtained showed that these farms presented good cattle health status. The raw milk tested was of a satisfactory hygienic quality, with great variability among milk samples in certain parameters, such as somatic cell count. This study confirmed the importance of consistent, ongoing control of safety conditions on dairy farms.

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