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1.
奶牛乳房炎是乳腺受到物理、化学、微生物刺激所发生的一种炎性变化.本病以乳汁的理化性改变为主,由多种非特定的病原微生物引起,不仅影响产奶量、牛乳质量、延长产后发情和妊娠时间,严重时还能使奶牛泌乳机能丧失而被淘汰,是世界奶牛业的主要危害因素之一[1-3].笔者根据多年的治疗经验,总结如下.  相似文献   

2.
The inoculation of 2000 colony-forming units of Corynebacterium pseudotuberculosis into one teat canal of each of three cows resulted in severe, chronic, pyogranulomatous mastitis. Within three days the cows had a reduced haematocrit, haemoglobin concentration and red cell count. The anaemia was initially normocytic, normochromic and non-regenerative, and was associated with a brief peak of neutrophilia; a regenerative response became evident two to three weeks later. Clinical signs of mastitis appeared seven to 14 days after the inoculation, with a peak of high fever, more severe anaemia, a second peak of neutrophilia and the complete cessation of milk production from all quarters; extensive and severe pyogranulomatous mastitis developed in the inoculated quarters. No other lesions were detected postmortem, and C pseudotuberculosis was cultured from the affected quarters but not from the supramammary lymph nodes and viscera.  相似文献   

3.
The development and test of detection models for oestrus and mastitis in dairy cows is described in a PhD thesis that was defended in Wageningen on June 5, 2000. These models were based on sensors for milk yield, milk temperature, electrical conductivity of milk, and cow activity and concentrate intake, and on combined processing of the sensor data. The models alert farmers to cows that need attention, because of possible oestrus or mastitis. A first detection model for cows, milked twice a day, was based on time series models for the sensor variables. A time series model describes the dependence between successive observations. The parameters of the time series models were fitted on-line for each cow after each milking by means of a Kalman filter, a mathematical method to estimate the state of a system on-line. The Kalman filter gives the best estimate of the current state of a system based on all preceding observations. This model was tested for 2 years on two experimental farms, and under field conditions on four farms over several years. A second detection model, for cow milked in an automatic milking system (AMS), was based on a generalization of the first model. Two data sets (one small, one large) were used for testing. The results for oestrus detection were good for both models. The results for mastitis detection were varying (in some cases good, in other cases moderate). Fuzzy logic was used to classify mastitis and oestrus alerts with both detection models, to reduce the number of false positive alerts. Fuzzy logic makes approximate reasoning possible, where statements can be partly true or false. Input for the fuzzy logic model were alerts from the detection models and additional information. The number of false positive alerts decreased considerably, while the number of detected cases remained at the same level. These models make automated detection possible in practice.  相似文献   

4.
Mastitis caused by the colourless alga Prototheca zopfii was diagnosed in 17 of 120 cows in a dairy herd. Infection occurred in animals varying from 3-14 years old and was present in one to four quarters of each cow. Nine cases were associated with clinical mastitis characterised by the presence in milk of flakes or small clots. Somatic cell counts consistent with subclinical mastitis (>500 x 10(3) cells/ml) were recorded in five of the eight remaining cows. Histological examination of udder tissue showed the presence of granulomatous lesions associated with the presence of Prototheca. The problem was identified and controlled by repeated microbiological examination of milk samples from all lactating cows and immediate culling of infected animals. P. zopfii was also recovered from environmental water samples on this farm. It is suggested that infection may have occurred as a result of teat sores caused by trauma from a milking machine, and the tendency for cows to lay down on a race, the surface of which was sometimes flooded by drain water in which Prototheca were present.  相似文献   

5.
Mastitis caused by the colourless alga Prototheca zopfii was diagnosed in 17 of 120 cows in a dairy herd. Infection occurred in animals varying from 3–14 years old and was present in one to four quarters of each cow.

Nine cases were associated with clinical mastitis characterised by the presence in milk of flakes or small clots. Somatic cell counts consistent with subclinical mastitis (>500 × 103 cells/ml) were recorded in five of the eight remaining cows.

Histological examination of udder tissue showed the presence of granulomatous lesions associated with the presence of Prototheca.

The problem was identified and controlled by repeated microbiological examination of milk samples from all lactating cows and immediate culling of infected animals.

P. zopfii was also recovered from environmental water samples on this farm. It is suggested that infection may have occurred as a result of teat sores caused by trauma from a milking machine, and the tendency for cows to lay down on a race, the surface of which was sometimes flooded by drain water in which Prototheca were present.  相似文献   

6.
7.
A range of clinical parameters were studied to assess their usefulness as objective markers of the severity of clinical mastitis in dairy cows. Cows with moderate clinical mastitis had significantly higher rectal temperatures and heart and respiratory rates than cows with mild clinical mastitis or control cows. The difference in temperature between quarters did not vary significantly between the control cows and the cows with mastitis, but there was a larger difference between quarter temperatures in the cows with moderate mastitis than in the cows with mild mastitis or the control cows. The hock-to-hock distance in the control cows was significantly smaller than in the cows with mild to moderate mastitis, but there was no significant difference in the distance either between the cows with mild mastitis and those with moderate mastitis, or between the cows with mastitis in the front quarters and those with mastitis in the hind quarters. The mechanical threshold to pain of the cows with mild and moderate mastitis was significantly lower than that of the control cows.  相似文献   

8.
An investigation was made using light and electron microscopy of the progressive pathological changes in nine experimental and two natural cases of severe Escherichia coli mastitis in dairy cows. The duration of infection varied from 18 hours to 13 days. Epithelial lesions were not found in glands which had been infected for more than 24 hours. However, the epithelia of the sinuses and large ducts became hyperplastic after 60 hours of infection and by six days hyperplasia was extensive on the crests of folds. The leucocyte response in the lumina of the glands and subepithelial tissue showed a progressive change from an acute neutrophil reaction to a chronic mononuclear cell infiltration within the first 36 hours of infection. The only changes affecting the secretory tissue occurred after six days of infection and were typical of mammary gland involution which was probably a direct consequence of anorexia.  相似文献   

9.
影响奶牛乳房炎抗性性状的贵传因素   总被引:1,自引:0,他引:1  
乳房炎是造成世界各国奶牛业中损失最多的一种疾病.当前严重依赖于抗生素治疗和疫苗预防来减少乳房炎的发生,这种方法并不十分奏效,而抗乳房炎育种则是一种很重要的替代方法.作者将从动物机体、细胞/激素和分子水平对影响奶牛乳房炎抗性性状的遗传因素进行论述,只有在遗传和免疫水平上具有优良特点的性状才能在获得乳房炎抗性的遗传改良中发挥作用.  相似文献   

10.
生物体内的微量元素、维生素在清除自由基的过程中发挥着重要的生理功能,微量元素铜(Cu)、锌(Zn)、硒(Se),锰(Mn)、铁(Fe)是某些抗氧化物酶的主要构成成分,发挥抗氧化作用;维生素A、维生素C、维生素E具有抗氧化作用,是生物体内良好的自由基清除剂[1].  相似文献   

11.
Ten Holstein cows were fed a selenium-deficient (SeD) diet containing 0.04 mg of Se/kg of dry matter for 3 months before and throughout their first lactation. A selenium-supplemented (SeS) group of 10 cows was fed an additional 2 mg of Se/head/d to increase dietary Se concentration of the dry matter to approximately 0.14 mg/kg of body weight. An intracisternal challenge exposure of 40 to 60 colony-forming units (CFU) of Staphylococcus aureus was administered into 1 or 2 quarters of the udder of each trial cow at about the twenty-second week of lactation. Blood Se concentration (micrograms/ml +/- SEM) at the time of challenge exposure was 0.035 +/- 0.002 in SeD and 0.139 +/- 0.006 in SeS cows. Infections were established in 14/16 of the challenge-exposed quarters in SeD and 16/19 of the challenge-exposed quarters in SeS cows. The infection in 1 quarter of each Se group cleared without treatment by the end of the 8-week trial period. Log10 peak bacterial concentrations in milk from infected SeD quarters (5.04 +/- 0.25 CFU/ml) were higher (P less than 0.05) than those of infected SeS quarters (4.40 +/- 0.12 CFU/ml). Log10 peak somatic cell count (SCC) in milk from infected SeD quarters (7.18 +/- 0.08 cells/ml) did not differ from that of SeS quarters (7.17 +/- 0.05 cells/ml). Peak bacterial concentrations were attained sooner (P less than 0.05) in SeD quarters (9.5 +/- 4.0 days) than in SeS quarters (20.7 +/- 3.1 days). Similarly, peak SCC were reached earlier (P less than 0.05) in SeD (4.3 +/- 1.1 days) than in SeS quarters (13.3 +/- 3.8 days).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
1 维生素E和硒 近年来的研究表明,乳房炎的感染受血浆维生素E和硒水平的影响。在日粮中添加维生素E和硒能够提高乳腺对感染的天然抵抗力。维生素E具有抗氧化作用,是所有脂类膜必不可少的组成部分,可消除细胞膜上的自由基,从而保护中性粒细胞的细胞膜免受自由基的攻击和过氧化损伤。维生素E对机体的免疫反应有重要影响,它不仅能增强机体的体液免疫反应,而且能提高细胞免疫功能和嗜中性白细胞杀伤金黄色葡萄球菌和大肠杆菌的能力。众多试验证  相似文献   

13.
乳腺炎是世界上最常见、最重要的奶牛疾病之一,每年乳腺炎给奶牛产业带来了巨大的经济损失,主要包括奶牛过早淘汰或死亡,高成本的兽药治疗以及滞销奶的成本等。乳腺炎主要是由接触性传染病原微生物或环境性病原体引起的,对上述两种乳腺炎的防治最好是通过预防而不是治疗。防控乳腺感染的手段除了在产奶期间加强管理外,疫苗接种是大部分奶牛场防止或减少临床乳腺炎发生而广泛采取的手段。本文就近年来临床上使用的不同类型的奶牛乳腺炎疫苗的应用进行总结,综述并比较了近几年不同类型的乳腺炎病原体疫苗在奶牛临床应用情况。  相似文献   

14.
A within cow comparison was made between milk progesterone levels in healthy and mastitic quarters. Material was collected from cows with mastitis induced by bacterial inoculation, or by inoculation with bacterial endotoxin. Furthermore material from cows with spontaneous subclinical mastitis was used. Milk progesterone levels were lowered due to mastitis. However, the decrease was not large enough to cause misinterpretation of where in the oestrous cycle (luteal phase or non-luteal phase) the samples were taken.  相似文献   

15.
Staphylococci are the most common and costly mammary disease of dairy cattle worldwide. Target of RNAIII Activating Protein (TRAP), a membrane associated 167AA protein, is highly conserved among staphylococci and was shown in Staphylococcus aureus to be involved in bacterial stress response. The aims of this study were to test the safety and efficacy of recombinant TRAP (rTRAP) vaccine in dairy animals. The vaccine was safe as 2-3 subcutaneous injections of rTRAP (54-100 μg) with adjuvant ISA 206 to cows and goats did not lead to any abnormal symptoms of sensitivity to the vaccine. The rTRAP vaccine was immunogenic and caused the induction of a humoral immune response that remained high for at least 160 d post second immunization. The rTRAP vaccine was efficacious; at parturition only 13.5% (5/37) heifers in the immunized group were infected with Staphylococcus chromogenes as compared to 42.9% (18/42) in the non-immunized group. Additionally, when cows were immunized in mid-lactation, the difference between somatic cell count (SCC) in immunized and control animals was profound (45 ± 7 vs. 470 ± 194, respectively). At the same time, the difference in milk yield was also evident (48.3 ± 1.4 L d(-1)vs. 44.3 ± 0.9 L d(-1), respectively). Put together, these studies indicate the value of the rTRAP vaccine in preventing new udder infections by staphylococci, which significantly lead to lowered SCC and some increase in milk yield. TRAP is conserved among all strains and species and is constitutively expressed in any strain of S. aureus or CNS tested so far, including those isolated from cows. TRAP may thus serve as a universal anti-staphylococcus vaccine.  相似文献   

16.
The necropsy records of dairy cows with mastitis were reviewed from the provincial veterinary laboratory in Guelph (44 cases of mastitis in nine years) and from the Ontario Veterinary College (168 cases in 14 years). Mastitis was considered to be the primary cause of death in 167 of 212 cows (79%). Of these 167 cases of mastitis, Escherichia coli was involved in 107 (64%), Klebsiella sp. in 12 (7%) and Staphylococcus aureus in 11 (7%). Bacteriology was not reported in 22 cases. Coliform mastitis, the most commonly identified type of fatal mastitis, was characterized histologically by the presence of infarcted areas in affected glands and by the lack of demonstrable bacteria, and was thus easily identified from fatal mastitis caused by S. aureus.  相似文献   

17.
The present study was aimed to investigate the relationship between selected morphological traits of teat and subclinical mastitis (SCM) in Frieswal crossbred dairy cows. A total of 1040 quarters from 261 lactating cows were evaluated for teat shape (bottle/fleshy/collapsed/conical/normal/pencil and short), teat-end shape (dished/flat/funnel/pocketed/pointed and rounded), teat orientation (aligned/misaligned) and teat position (front and rear; left-sided and right-sided). Each udder quarter was screened with California Mastitis Test (CMT) for the purpose of defining quarter health status. Data were analysed using Chi-square test and multivariable logistic regression procedure. An overall prevalence of SCM (CMT positive) at quarter level was 30.6%. Most of the teats had normal or cylindrical shapes (48%), dished teat-ends (40.7%), and aligned (central or squared) in orientation (65%). At bivariable level, significant association of SCM with teat shape, teat position, teat orientation, parity, and stage of lactation was observed (P < 0.05 to P < 0.001). Teat-end shapes showed some association with SCM (P = 0.07). Results of multivariable analysis showed that pencil-shaped teats were least associated with SCM (P < 0.05) as compared to other teat shapes. Prevalence of SCM was also higher in rear teats (P = 0.015), misaligned teats (P = 0.01), and cows in second or higher parities (P < 0.01) and late stage of lactation (P < 0.001). The results of the present study indicate that selected morphological traits of teat are associated with SCM in Frieswal crossbred cows; therefore, selection towards desirable morphological traits could help reduce mastitis in this breed.  相似文献   

18.
《畜牧与兽医》2020,(3):145-150
乳腺炎是奶牛养殖过程中最常见的疾病,可造成畜牧业的重大经济损失。蜂胶作为一种动植物双源性天然药物,具有包括抗菌消炎在内的多种生物学活性及药理学作用,能替代传统抗生素应用在奶牛乳腺炎的防治过程中。本文在概括了奶牛乳腺炎的病因、临床症状、发病过程、治疗手段的基础上,重点综述了近年来在利用蜂胶防治奶牛乳腺炎的研究和应用进展,为临床上利用蜂胶防治奶牛乳腺炎提供参考。  相似文献   

19.
乳房炎是成年奶牛最常见的一种疾病,发病率可达30%(Gardner等,1990),奶牛生产单位每年因乳房炎导致的淘汰率约10%,占牛群总淘汰率的1/2左右[1].乳房炎可以降低奶牛产奶量(下降10%~15%)、增加医疗费用支出,从而造成严重的经济损失;此外,乳房炎还会降低牛奶品质、造成牛奶的公共卫生安全隐患[1-3].  相似文献   

20.
OBJECTIVE: To determine the incidence of bacteremia in dairy cows with naturally occurring acute coliform mastitis (ACM) with a wide range of disease severity. DESIGN: Cohort study. ANIMALS: 144 dairy cows with ACM from 6 herds. PROCEDURE: Cows were examined at time of identification of ACM (time 0) and classified as having mild, moderate, or severe mastitis on the basis of rectal temperature, hydration status, rumen contraction rate, and attitude. Cows were reexamined at 24 or 48 hours. Bacteriologic culturing of milk and blood (30 ml), CBC, and serum biochemical analysis were performed at each time point. Appropriate samples were obtained at a single point from herdmates without mastitis (controls) that were closely matched for lactation number and days since parturition. Blood culture results were compared among severity groups and controls by use of chi2 tests, as was outcome of an ACM episode for cows grouped by blood bacterial isolates. RESULTS: Bacteria were isolated from 52 blood samples from 46 of 144 (32%) cows with ACM, which was significantly more than control cows (11/156; 7.1%). Group-1 isolates (Escherichia coli, Pasteurella multocida, Mannheimia haemolytica, Klebsiella pneumoniae, Enterobacter agglomerans, and Salmonella enterica serotype Typhimurium) were identified in 20 of 144 (14%) cows with ACM and 0 of 156 control cows. Group-1 isolates were identified in 4.3, 9.1, and 42% of cows classified as having mild, moderate, and severe ACM, respectively. Escherichia coli and K pneumoniae milk and blood isolates obtained from the same cow were of the same genotype. Bacillus spp were identified in 21 of 144 (15%) cows with ACM, which was significantly more than control cows (3/156; 1.9%). Thirty-five percent of cows with a group-1 isolate died during the mastitis episode. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that bacteremia develops in a substantial proportion of cows with ACM. Classification of severity of disease is important for establishment of effective treatment protocols; parenteral antimicrobial treatment may be indicated in cows with ACM.  相似文献   

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