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1.
The objectives of this study were to evaluate and compare the effect of working vacuum levels (35 and 44 kPa) and liners dimensions (mouthpiece lip diameter and overall length, 20–185 and 22–170 mm) on the main milking characteristics of goats. The results highlight that both the working vacuum level and the liner dimension have influenced the milk flow curve parameters. The maximum variations were found for peak flow rate, which increased significantly with liner dimensions of 20–185 mm at a working vacuum level of 44 kPa as well as average milk flow rate and for plateau phase duration. The incorrect adoption of operative parameters and unsuitable milking machine components, might affect the performance of the mechanical milking and negatively affecting animal productions and welfare.  相似文献   

2.
The disinfection effect of slightly acidic electrolyzed water (SAEW) use in a farm where Pseudomonas mastitis has spread was evaluated. Despite the application of antibiotic therapy and complete cessation of milking infected quarters, numerous new and recurrent Pseudomonas aeruginosa clinical mastitis infections (5.8–7.1% of clinical mastitis cases) occurred on the farm from 2003 to 2005. Procedural changes and equipment modifications did not improve environmental contamination or the incidence of Pseudomonas mastitis. To more thoroughly decontaminate the milking parlor, an SAEW system was installed in 2006. All milking equipment and the parlor environment were sterilized with SAEW (pH 5–6.5, available chlorine 12 parts per million) before and during milking time. After adopting the SAEW system, the incidence of clinical and subclinical Pseudomonas mastitis cases decreased significantly (< 0.0001) and disappeared. These findings suggest that SAEW effectively reduced the incidence of mastitis in a herd contaminated by Pseudomonas species. This is the first report to demonstrate the effectiveness of disinfection by SAEW against mastitis pathogens in the environment.  相似文献   

3.
In conventional milking systems, dairy cows are driven to the milking stall twice or thrice daily, whereas in automatic milking systems (AMS), the cows enter the milking stall voluntarily. In this study, noninvasive methods were used to analyze the physiological reaction of 17 cows toward the changeover from conventional to automatic milking. Milk yield and composition were analyzed. Heart rate was recorded continuously, and feces was sampled twice daily to determine cortisol metabolites (11, 17-dioxoandrostanes) for a period of 2 wk. During the first visit to the AMS (without milking), heart rate was elevated compared with parlor milking by 35 +/- 3 beats per minute (bpm) above basal heart rate (P < 0.05). Heart rate during the first milking in AMS (eighth visit) was already similar to the heart rate previously measured during milking in the parlor (18.1 +/- 2.2 bpm above basal level). Concentration of fecal cortisol metabolites was unchanged during the change-over compared with parlor milking. A decreased (P < 0.05) milk yield of 68 +/- 7% relative to previous parlor yield during the first AMS milking indicated a disturbance of milk ejection in most cows. Individual yields ranged from 8 to 96% of the previous parlor yield. To examine the relationship between adrenal cortex sensitivity and the coping process, an ACTH challenge experiment was performed after the changeover period. Cows that released more cortisol after ACTH injection, indicating a higher adrenal cortex sensitivity, had a less enhanced heart rate and a near normal milk ejection during the first AMS milkings (P < 0.05). In conclusion, the reactions toward the changeover to AMS milking varied widely within cows. Adaption to the AMS was easier in animals with a higher adrenal cortex sensitivity to ACTH.  相似文献   

4.
本研究对规模化奶牛场产奶牛和育成牛粪中污染因子进行了四季监测,结果表明,鲜粪中含水率两类牛群夏季最高、春季最低;风干粪样中,除产奶牛夏季全氮和全磷外,产奶牛和育成牛5项检测指标及其年均值的季节变化规律均保持一致,即有机质>全氮>全磷>锌>铜;两类牛群全磷含量夏季最高、秋季最低,有机质含量春季最高、夏季最低,铜和锌含量夏季均最低;产奶牛全氮含量夏季最低、春季最高,铜含量春季最高,锌含量冬季最高;育成牛全氮含量夏季最高、秋季最低,铜含量秋季最高,锌含量春季最高.  相似文献   

5.
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   

6.
Efforts to improve dairy performance have been focused on increasing milk productivity of cows through improved feeding systems and genetic potential. However, methods for evaluating milking system performance based on milk productivity have not yet been established. Milking system performance was evaluated by measuring the claw vacuum at five flow rates (1.9–8.7 kg/min) produced using a flow simulator for a single eight‐swing milking parlor with a high‐line system. Based on these results, a double eight‐parallel milking parlor with a low‐line system was installed and tested. Farmers can take data obtained from evaluations of milking system performance into account for future management decisions, such as renewing the milking system. By renewing the milking system, average milking productivity, somatic cell linear score (LS) of bulk milk, and LS of each cow were significantly improved in the year after installing the new system (p < .01). In addition to checking conventional milking systems, this novel diagnostic method using a flow simulator can be used for checking new installations and also for proposing renovations.  相似文献   

7.
An on-farm experiment was performed to investigate the effects of two milking systems on teat condition. An auto-tandem milking parlor made by GEA® with a conventional milking cluster (CON) and a single tube milking system called MultiLactor® (MULTI) from Siliconform GmbH were tested. For both milking system, in total 73 animals were milked over a period of seven months. To assess the effect of milking on teat condition, each teat was scored according to teat-condition evaluation systems. To evaluate teat condition, the teat color, ring formation at the teat base and formation of teat hyperkeratosis were assessed. The evaluation was conducted once a month after milking. The collected data were then statistically analyzed with generalized linear mixed models. The only differences found between the two milking systems occurred with respect to their effect on teat color. MULTI showed significantly better scores compared to CON. There were no significant differences between the milking systems with regard to teat-end hyperkeratosis and ring formation at the teat base.  相似文献   

8.
Cleanliness of milking equipment is known to be important for the safety of dairy products and to prevent the spread of diseases among cows. We investigated the cleaning procedures of milking equipment and suckling equipment on Japanese dairy farms, and the cleanliness of bucket milkers, suckling buckets, milk receivers, and bulk tanks, using adenosine triphosphate (ATP) bioluminescence test. Bulk tanks (except one bulk tank) and milk receivers were washed by automated cleaning, but all bucket milkers and suckling buckets were washed by manual cleaning. Detergents were often not used to clean bucket milkers and suckling buckets. The log10 transformed relative luminescence units (LRLU) of equipment washed by manual cleaning was higher than equipment washed by automated cleaning. Clean surfaces (≤2.2 LRLU) were only observed on the bulk tank and the milk receiver. More than 50% of the LRLU of the mouthpiece, the rubber packing of claw, and the nipple of the suckling bucket were determined dirty. These results suggest that the cleanliness of the bucket milkers and the suckling buckets washed by manual cleaning was lower than that of the equipment washed by automated cleaning, and may be due to insufficient cleaning procedures.  相似文献   

9.
Nonclinical Pseudomonas aeruginosa mastitis in a dairy herd   总被引:1,自引:0,他引:1  
Atypical Pseudomonas aeruginosa mastitis in a dairy herd was characterized by nonclinical mastitis that responded to antibiotic treatment, but only for the cows to become reinfected because of a persisting source of contamination in the milking parlor wash water. At least 36% of the cows were infected during a 37-month period. The source of infection was contaminated water, wash hoses, and spray nozzles in the parlor. After the source of infection was removed and long-term control measures were instituted, the nonclinical infections became less severe and shorter in duration and they occurred for a lesser percentage of the lactation period.  相似文献   

10.
Mastitis caused by Prototheca spp or Nocardia spp is considered to be difficult to treat. Both microorganisms are contaminants commonly found in soil. The occurrence of mastitis caused by these agents was studied in a particular dairy farm. In this herd, the animals were kept at pasture overnight and during daytime were brought to a pen where they were fed. This pen accumulated mud and faeces, particularly in the rainy season. During milking, pre-dipping of the teats was performed with an iodide solution, but they were not washed, so a layer of soil and faeces remained which may have contaminated the milking equipment. The herd comprised 91 lactating animals and 47 dry cows. For microbiological examination, 107 milk samples were collected from lactating cows and 186 samples of mammary secretions from the dry cows. Prototheca spp were isolated from 14.55% of the milk samples and Nocardia spp from 4.55%. Prototheca spp were isolated from 8.06% of the secretion samples from dry cows and Nocardia spp were isolated from 2.15% samples. The high occurrence of mastitis due to these environmental agents reflects the problem of keeping animals in muddy pastures and pens, and the defective pre-milking hygiene for the teats.  相似文献   

11.
以3个批次的桂香鸡为研究对象,分析120日龄时桂香鸡的胫长、胫围以及体重之间的相关性。研究结果表明,第3批桂香鸡的120日龄体重和胫围显著高于第1批(P〈0.05),第2批和第3批桂香鸡的120日龄胫长显著高于第1批(P〈0.05)。相关分析表明,第1批桂香鸡120日龄体重和胫长以及胫围之间存在极显著的相关(P〈0.01),相关系数分别为0.583和0.623;120日龄胫长和胫围之间存在极显著的相关(P〈0.01),相关系数为0.369。第2批和第3批数据合并分析表明,桂香鸡120日龄体重和胫长以及胫围之间存在极显著的相关(P〈0.01),相关系数分别0.605和0.726;120日龄胫长和胫围之间存在极显著的相关(P〈0.01),相关系数为0.463。研究结果为桂香鸡胫长、胫围与体重性状的选择,尤其是桂香鸡胫长、胫围与体重性状的综合选择提供了参照。  相似文献   

12.
Commercial dairy cows milked in a parlor system are packed close together in the holding area before milking. The present study examined the relationships of ‘looking up’ behavior with some other behaviors and the productivity of 1116–1153 cows from five farms. The individual identities of the cows looking up in the holding area were recorded at 5 min intervals during six intermittent afternoon milking sessions. Entrance into the milking parlor and the numbers of steps and kicks by cows while the milking person was attaching the milking cups, were recorded in six milking sessions. Flight responses in the pasture after milking were recorded over four days intermittently. The frequency of ‘looking up’ behavior weakly, but significantly correlated with flight starting distance (r = 0.10, P < 0.05), while the correlation with the number of step‐kicks during milking was not significant. As for productivity, lactation number (r = ?0.18, P < 0.001), milk yield (r = ?0.15, P < 0.001) and fat content (r = ?0.15, P < 0.001) were negatively correlated with the frequency of ‘looking up’ behavior. Age of cows was correlated with the frequency of ‘looking up’ behavior as well as lactation number (r = ?0.21, P < 0.001). Entrance order was positively correlated with the frequency of ‘looking up’ behavior (r = 0.15, P < 0.001). The ‘looking up’ behavior was observed more frequently in cows in their third or less lactation compared with cows which were in their fourth or greater lactation (P < 0.05). The lactation number of cows was correlated with their milk yield (r = 0.36, P < 0.001) and flight starting distance (r = ?0.21, P < 0.001). In conclusion, ‘looking up’ behavior shown by cows in the holding area before milking might be an indicator of low motivation for milking, mainly because of fear of humans, and an aversion to milking caused by insufficient experience in being milked.  相似文献   

13.
The milking of Salers cows requires the presence of the calf. The removal of the calf would simplify the milking routine, but it could also modify the milk yield and the milk and cheese composition. Therefore, the aim of this experiment was to evaluate the effect of calf presence during milking during sampling period (winter or grazing periods), on dairy performance, milk fatty acid (FA) composition, lipolysis and cheese yield and composition. Nine and 8 Salers lactating cows were milked in the presence (CP) or absence (CA) of their calves respectively. During winter, the cows were fed a hay‐based diet and then they only grazed a grassland pasture. Calf presence during milking increased milk yield and milk 16:0 concentration and decreased milk fat content and milk total odd‐ and branched‐chain FA (OBCFA) concentrations. Calf presence only increased initial lipolysis in milk collected during the winter season. Milk from CP cows compared to CA cows resulted in a lower cheese yield and ripened cheeses with lower fat content. Milk from the grazing season had lower saturated medium‐chain FA and OBCFA concentrations and higher 18:0, cis‐9‐18:1, trans‐11‐18:1 and cis‐9, trans‐11‐CLA concentrations than that from the winter season. Initial milk lipolysis was higher in the winter than in the grazing season. These variations could be due to seasonal changes in the basal diet. Furthermore, the effect of calf presence during milking on milk fat composition was lower than that on dairy performance, cheese yield and composition. Removing the calf during the milking of Salers cows seems feasible without a decrease in milked milk, and with a positive effect on cheese yield and fat content, under the condition that we are able to select cows having the capacity to be milked easily without the calf.  相似文献   

14.
Eight Danish Holstein cows were milked with a 1-mm thick specially designed soft liner on their right rear teat and a standard liner mounted under extra high tension on their left rear teat. Four of the animals were overmilked for 5 min. Rear teats were subjected to ultrasound examination on the first day and to infrared thermography on the second day. Teats were submersed in ethanol 20 min post-milking on the second day. Ultrasonography measurements showed that teat canal length increased by 30-41% during milking. Twenty minutes after milking, teats milked with modified standard liners still had elongated teat canals while teats milked with the soft liner were normalized. Overmilking tended to increase teat wall thickness. Approximately 80% of variability in teat canal length, from before teat preparation to after milking, could be explained by changes during teat preparation. Thermography indicated a general drop in teat temperature during teat preparation. Teat temperature increased during milking and continued to increase until the ethanol challenge induced a significant drop. Temperatures approached pre-challenge rather than pre-milking temperatures within 10 minutes after challenge. Teat temperatures were dependent on type of liner. Mid-teat temperatures post-challenge relative to pre-teat preparation were dependent on overmilking. Thermography and ultrasound were considered useful methods to indirectly and non invasively evaluate teat tissue integrity.  相似文献   

15.
Three experiments examined the extent of behavioral interactions between housed dairy cows. In Experiment 1, 6 different cows were selected every other day from a dairy herd and allocated to 3 pairs for recording of feeding, standing, lying, and leg-raising behaviors. There was no difference in the between-pair and within-pair coefficients of variation for the behaviors, suggesting that the performance of these behaviors was independent of influences of other cows. Experiment 2 used 9 pairs of cows in a 3-period changeover design. The same behaviors were recorded as in Experiment 1, and data were used only from the last 2 periods, which ensured that cows had been together previously for at least one 48-hour period. There were again no differences in the between- and within-pair coefficients of variation when using behaviors as replicates, either for the first 2 hours, during which time no treatments had been applied, or the entire 4 hours, when some cows had been prevented from lying down and feeding. Experiment 3 investigated the consistency of between-cow associations for repeated observations of feeding, lying, and entering the milking parlor. Although there was evidence of a similar order of entry into the milking parlor between days, the number of feeding associations was similar to that predicted by a model of random behavior, and the pattern of lying associations also suggested a random pattern of associations. Across behaviors, cows were observed with specific partners more often than expected by chance. Thus although there was no evidence of interdependence of feeding, lying, or standing behavior, consistent associations were observed, particularly in parlor entry.  相似文献   

16.
: Friesian-type dairy cows were milked with different machine settings to determine the effect of these settings on teat tissue reaction and on milking characteristics. Three teat-cup liner designs were used with varying upper barrel dimensions (wide-bore WB = 31.6 mm; narrow-bore NB = 21.0 mm; narrow-bore NB1 = 25.0 mm). These liners were tested with alternate and simultaneous pulsation patterns, pulsator ratios (60:40 and 67:33) and three system vacuum levels (40, 44 and 50 kPa). Teat tissue was measured using ultrasonography, before milking and directly after milking. The measurements recorded were teat canal length (TCL), teat diameter (TD), cistern diameter (CD) and teat wall thickness (TWT).Teat tissue changes were similar with a system vacuum level of either 50 kPa (mid-level) or 40 kPa (low-level). Widening the liner upper barrel bore dimension from 21.0 mm (P < 0.01) or 25.0 mm (P < 0.001) to 31.6 mm increased the magnitude of changes in TD and TWT after machine milking. Milk yield per cow was significantly (P < 0.05) higher and cluster-on time was reduced (P < 0.01) with the WB cluster as compared to the NB1 cluster. Minimum changes in teat tissue parameters were achieved with system vacuum level of 40 kPa and 50 kPa using NB and WB clusters, respectively. Similar changes in teat tissue and milk yield per cow were observed with alternate and simultaneous pulsation patterns. Widening pulsator ratio from 60:40 to 67:33 did not have negative effects on changes in teat tissue and had a positive effect on milk yield and milking time. Milk liner design had a bigger effect on teat tissue changes and milking characteristics than pulsation settings.  相似文献   

17.
【目的】 探究荷斯坦牛泌乳速度相关指标的群体规律及非遗传因素对其的影响。【方法】 收集华东地区某规模化牧场8 757头泌乳牛的906 748条挤奶记录,定义了班次产奶量、前两分钟产奶量、挤奶时间、前两分钟产奶量占比、平均流速和最高流速6个泌乳速度指标,并对其进行了描述性统计,计算了各指标间的Pearson相关系数,采用固定模型分析了测定季节、胎次、泌乳阶段、初产月龄和挤奶班次对泌乳速度相关指标的影响。【结果】 6个泌乳速度指标中,除前两分钟产奶量占比之外,班次产奶量、前两分钟产奶量、挤奶时间、平均流速和最高流速均基本呈对称分布,各个指标的变异较大,变异系数在30%左右;各指标两两之间存在极显著相关关系,相关系数在-0.84~0.89之间,泌乳速度与产奶量呈中等或强相关,与挤奶时间呈弱负相关,与前两分钟产奶量占比呈弱正相关。测定季节、胎次、泌乳阶段、初产月龄和挤奶班次对泌乳速度指标均有极显著影响(P<0.01);不同季节中,冬季的班次产奶量和挤奶时间最大,夏季的平均流速最快,而秋季的最高流速最快;不同泌乳阶段中,在第Ⅱ泌乳阶段(45~99 d),奶牛的班次产奶量、挤奶时间、平均流速和最高流速均最大;不同班次中,在夜间班次(00:00—06:00),奶牛的班次产奶量、挤奶时间、平均流速和最高流速均为最大。【结论】 奶牛泌乳速度指标存在较大变异,对季节、胎次等环境和生理因素较为敏感,可为奶牛产奶性能的选育提供信息。  相似文献   

18.
In March 1989, the USDA Food Safety and Inspection Service sampled raw chicken carcasses and giblets at a federally inspected slaughter establishment in Puerto Rico to determine the effects of adding chlorine to carcass and giblet chill water on bacterial contents of raw poultry products. Over four 8-hour workdays, 200 carcass rinse samples were collected at 3 sites in the establishment; 39 giblet rinse samples were collected at 1 site. Analyses of the carcass rinse samples indicated that carcasses had average aerobe plate counts of log10 3.20 before chilling and 2.51 after chilling; Enterobacteriaceae counts of log10 2.57 before chilling and 1.75 after chilling; and Escherichia coli counts of log10 2.04 before chilling and 1.20 after chilling. Salmonellae were found on 43% of the carcasses before chilling and on 46% after chilling. Analyses of the giblet and neck rinse samples indicated that raw giblets and necks after chilling had average aerobe plate count of log10 3.49, Enterobacteriaceae count of log10 2.57, and E coli count of log10 1.06. Salmonellae were found on 12% of the giblets and necks sampled. Results compared favorably with giblet and neck rinse sample results obtained during a baseline sampling study in November and December 1987. The baseline results indicated aerobe plate count of log10 3.72; Enterobacteriaceae count of log10 2.90; E coli count of log10 1.14; and salmonellae on 69% of the giblets and necks sampled. Placing raw chicken carcasses in chlorinated chill water reduced aerobe, Enterobacteriaceae, and E coli plate counts. Prevalence of carcasses with salmonellae remained nearly the same.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Under the conditions of large-scale breeding, seasonal changes in the total protein of colostrum whey, gammaglobulins, vitamins A, E, C, and carotene in cow's colostrum from the first milking, were studied in the course of the first 12 months. As indicated by the results of an analysis of 302 colostrum samples, the concentrations of total protein in whey were significantly higher in winter (P less than 0.01) than in the summer season. On the other hand, vitamin C levels were higher in summer than in winter. A lower level of total protein of colostral serum than the required minimum of 120 g per litre was recorded in 64.4% of the cows. A highly positive correlation (r = +0.981) was demonstrated between the concentration of total protein and gammaglobulins in colostrum whey. This fact makes it possible to consider and use for diagnostic purposes the total protein of whey as a sufficiently exact parameter of colostrum quality without having to determine the gammaglobulin level. On the basis of these analyses it is possible to some extent not only to evaluate the health condition of high-pregnant cows and the quality of attendance, but also to prognosticate the health of their calves.  相似文献   

20.
No differences in blood samples were found out when the biochemical parameters in arterial and venous blood of dairy cows were compared before and after milking. Negative correlation coefficient (r = -0.3460) approaching the significance level was determined by comparing the values for milk yield on the day of sampling (in ascending phase of lactation) and protein content in venous blood after milking, and significant negative correlation coefficient (r = -0.3813) for daily milk yield and gamma-globulin concentration in venous blood before milking. The relationship between butterfat content on the day of milking and the values of alkaline phosphatase can be characterized by significant up to highly significant negative correlation coefficients in all three blood samples (r = -0.3232 to -0.3908).  相似文献   

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