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1.
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   

2.
A naturally occurring case of chronic mastitis caused by Prototheca zopfii was detected in a dairy cow. The cow was observed for 12 weeks, and milk samples were cultured each week. Milk production was decreased, and high numbers (greater than 10(3)/ml) of the organism were detected in the milk. Six glands of 2 cows were inoculated with small numbers of P zopfii. All 3 cows were euthanatized, and at postmortem, a progressive pyogranulomatous inflammation was observed in all infected mammary glands. The organism was recovered from tissue and secretions from all inoculated glands and from lymph nodes draining these glands but not from other tissues.  相似文献   

3.
Occurrence of Prototheca zopfii, a mastitis pathogen, in milk   总被引:1,自引:0,他引:1  
Prototheca zopfii was isolated from cow-composite milk and bulk tank milk by a new selective Prototheca enrichment method. Repeated testing of cow-composite milk from individual cows resulted in P. zopfii isolation data indicating a strong statistical correlation of P. zopfii with specific cows. Prototheca sp. were isolated from the milk of 31 of 79 cows in a single herd, and contamination was discounted as the source. Prototheca sp. were also recovered from 28 of 787 bulk tank milk samples from the Eastern U.S.A., and 22 of 69 temperature control milk samples from pooled dairy farm milk from delivery trucks.  相似文献   

4.
This study is the first investigation on Japanese isolates of Prototheca zopfii from bovine mastitis and the cow-barn surroundings by molecular characterization to clarify routes of infection for bovine protothecal mastitis. We performed isolation of Prototheca from cow-barn surroundings (drinking water, sewage and feces) and milk samples from cases of bovine mastitis. Genotypes of the 32 isolates of P. zopfii from cow-barn surroundings and 67 isolates from mastitis were analyzed by genotype-specific PCR assays and restriction fragment length polymorphism (RFLP) assays. All mastitis isolates were identified as P. zopfii genotype 2. Conversely, 29 isolates from cow-barn surroundings were identified as P. zopfii genotypes 1 and 3 isolates as genotype 2, respectively. Given these results, both genotypes of P. zopfii could exist in cow-barn surroundings, but no sites were identified as frequent sources of P. zopfii genotype 2. P. zopfii isolates should thus be further explored with regard to genotype to clarify the reservoir of etiological agents in bovine Prototheca mastitis.  相似文献   

5.
目前已有12个国家报道无绿藻性奶牛乳房炎,造成严重的经济损失并对公共安全存在潜在的危害.2010年春季,北京地区某奶牛场暴发中型无绿藻引起的临床型乳房炎.从患有临床型乳房炎的10头奶牛的11个乳区分离到8株酵母样微生物,鉴定为中型无绿藻.用16种抗生素药敏纸片进行药敏试验,结果显示中型无绿藻仅对庆大霉素、链霉素和阿米卡星等氨基糖苷类抗生素敏感.同化试验证明该分离株能发酵葡萄糖和丙三醇.本试验在我国首次报道了中型无绿藻能引起奶牛临床型乳房炎.  相似文献   

6.
In the last 2 years 223 cases of bovine mastitis caused by Prototheca zopfii infection were identified in 32 large-scale dairy herds. All of these farms were in Hungary, which has a continental type, temperate zone climate. Both the sporadic and epidemic forms of P. zopfii mastitis were observed. All the herds affected by the epidemic form had poor hygienic conditions and suffered from several managerial faults, but no specific predisposing factors could be identified. In almost all of the cases, the type II variant of this pathogen was isolated; however, the type III variant was isolated from three cows. The cows had a higher chance of new infection in the early weeks of lactation and in the summer. The P. zopfii infection usually resulted in a chronic subclinical, or mild clinical, inflammatory process in the udder, and was followed by a dramatic loss in milk production and a permanent increase in somatic cell count. The histopathological findings could be characterized as a progressive interstitial mastitis associated with alveolar atrophy. The self-recovery rate was very low.  相似文献   

7.
Sources of Prototheca spp in a dairy herd environment   总被引:1,自引:0,他引:1  
A source of Prototheca spp causing mastitis in a herd of 263 milking cows in North Carolina was investigated. Of 38 samples from the dairy environment, 18 (47%) contained Prototheca spp. Isolation sites included cattle drinking water; a feed trough; mud, dirt, and excreted feces from a dirt lounging area; water, sludge, mud, and vegetation from a creek in the lounging area; and the floor of a freestall barn. Samples were collected from 5 additional dairies, including one dairy with and 4 dairies without a history of protothecal mastitis. Prototheca spp were isolated from 48 (25%) of 190 samples from various sites on all 6 dairies. Isolates were P zopfii (45; 94%) and P wickerhamii (3; 6%). Isolation frequency ranged from 4 to 47% of samples/dairy. There was no apparent difference in the isolation frequency of Prototheca spp from samples from dairies with or without a history of protothecal mastitis. Sites characterized by wetness and the presence of organic matter most commonly yielded Prototheca spp. Because Prototheca spp appear to be common in the dairy environment, factors in addition to presence in the environment may be important in development of protothecal mastitis.  相似文献   

8.
Protothecosis is a severe form of mastitis in dairy cows caused by colorless algae of the genus Prototheca. Since P. zopfii is highly resistant to all known chemotherapeutics, infected cows must be removed from the herd. Eradication measures are difficult since many chronically infected cows may become intermittent shedders. Therefore, cultural methods are insufficient for control measures. In order to eradicate Prototheca zopfii-mastitis in dairy cattle herds, two isotype specific indirect ELISA for detection of IgA and IgG1 in whey were used in a dairy herd highly affected with protothecal mastitis. All cows (n = 313) were tested four times in intervals of six months. Milk specimens were examined in parallel by cultivation and serologically using two indirect ELISA systems for specific IgA and IgG1 in whey. Cows tested Prototheca positive were consequently separated from the herd and slaughtered. At the first examination, 15.6% of the animals were found positive by culture, and 23.3% were positive in at least one of the ELISA systems. Within two years, protothecal prevalence and incidence decreased to zero indicating that the eradication strategy used was successful. In summary, serological identification of P. zopfii-infected lactating cows is an useful tool to eradicate protothecal bovine mastitis in infected herds.  相似文献   

9.
It was the objective of this study to analyse shedding patterns and somatic cell counts in cows and quarters infected with Prototheca spp. and to evaluate two approaches to identify infected animals by somatic cell count (SCC) or by bacteriological analysis of pooled milk samples. Five lactating dairy cows, chronically infected with Prototheca spp. in at least one quarter were studied over 11 weeks to 13 months. Quarter milk samples and a pooled milk sample from 4 quarters were collected aseptically from all quarters of the cows on a weekly basis. Culture results of quarter milk and pooled samples were compared using cross tabulation. SCC of quarter milk samples and of pooled samples were related to the probability of detection in the infected quarters and cows, respectively. Shedding of Prototheca spp. was continuous in 2 of 8 quarters. In the other quarters negative samples were obtained sporadically or over a longer period (1 quarter). Overall, Prototheca spp. were isolated from 83.6% of quarter milk samples and 77.0% of pooled milk samples of infected quarters and cows. Somatic cell counts were higher in those samples from infected quarters that contained the algae than in negative samples (p < 0.0001). The same applied for composite samples from infected cows. Positive samples had higher SCC than negative samples. However, Prototheca spp. were also isolated from quarter milk and pooled samples with physiological SCC (i.e. < 10(5)/ml). Infected quarters that were dried off did not develop acute mastitis. However, drying off had no effect on the infection, i.e. samples collected at calving or 8 weeks after dry off still contained Prototheca spp. Results indicate that pre-selection of cows to be sampled for Prototheca spp. by SCC and the use of composite samples are probably inadequate in attempts to eradicate the disease. However, due to intermittent shedding of the algae in some cows, single herd sampling using quarter milk samples probably also fails to detect all infected cases. Therefore, continuous monitoring of problem cows with clinical mastitis or increased SCC in herds during eradication programs is recommended.  相似文献   

10.
11.
Bovine mastitis caused by Prototheca zopfii: a case study   总被引:1,自引:0,他引:1  
An outbreak of severe indurative mastitis in newly calved cows, from which Prototheca zopfii was isolated, is described. The refractory nature of this type of mastitis and the ineffectiveness of the presently available intramammary preparations are highlighted.  相似文献   

12.
To elucidate the spectra of Prototheca species and P. zopfii genotypes in milk samples from mastitis affected cattle, 200 Prototheca-isolates of 57 German dairy cattle barns were analyzed by species- and genotype- specific PCR and RFLP analysis. The investigations showed that 177 (88.5%) of all isolates represented P. zopfii genotype 2, 21 (10.5%) isolates represented P. blaschkeae and two (1.0%) P. zopfii genotype 1. Therefore mainly P. zopfii genotype 2 but also P. blaschkeae act in the epidemiology of mastitis in cattle, whereas the role of P. blaschkeae in development of bovine protothecal mastitis should be further explored in epidemiological studies. In this study P. blaschkeae was demonstrated for the first time in association with bovine mastitis in Germany.  相似文献   

13.
Bovine mastitis due to unicellular, achlorophyllous algae of the genus Prototheca is a serious and complex ailment that accounts for high economic losses in the dairy industry. Bovine protothecal mastitis has been almost exclusively associated with only one species Prototheca zopfii. Recently, based on the 18S rDNA sequence analysis, P. zopfii has been divided into three genotypes (1-3), of which P. zopfii genotype 3 has been given the status of a new species Prototheca blaschkeae sp. nov. The aim of this study was to investigate the genotypic composition of the population of P. zopfii bovine mastitis isolates from Poland, according to that threefold classification. Of the 44 isolates tested, 43 (98%) were identified as P. zopfii genotype 2. Only one isolate was assigned to the newly established P. blaschkeae species. These findings clearly show the predominance of the P. zopfii genotype 2 in the etiology of bovine mammary protothecosis in Poland, but also underline the involvement of P. blaschkeae in the disease. The study is the first to provide molecular characterization of Polish P. zopfii mastitis isolates, collected from different regions of Poland.  相似文献   

14.
Antibacterial activity of bovine lactoferrin hydrolysates (LFH) on microorganisms isolated from bovine mastitis, and superoxide (O(2)(-)) production of bovine neutrophils were evaluated. Antibacterial effects of LFH were measured in vitro against Staphylococcus aureus, coagulase-negative staphylococci, Streptococci, Enterococci, Escherichia coli, Klebsiella pneumoniae, yeast-like fungi and Prototheca zopfii isolated from clinical cases of bovine mastitis. To compare susceptibilities against LFH, minimal inhibitory concentration (MIC) values were determined by a micro-plate assay method. Most organisms were sensitive to LFH. Prototheca zopfii was highly sensitive to LFH; the growth of the microorganism was inhibited completely even at 1 mug/ml. Staphylococcus aureus and Escherichia coli were resistant to LFH. The production of O(2)(-) by bovine neutrophils was used to evaluate the effect of LFH administration on functional activity. Increase in O(2)(-) production by bovine neutrophils occurred upon addition of LFH to neutrophils. These results demonstrate that LFH possesses antibacterial activity against pathogens that cause mastitis and activates neutrophil superoxide production.  相似文献   

15.
The mastitis caused by P. zopfii alga is a disease of high-producing, machine-milked dairy cows. It occurs worldwide in tropical and temperate climatic areas, and mostly appears sporadically in a therapy-resistant form. However, in poorly managed dairy herds it may be endemic, causing serious economic losses as a result of decreased milk quality and quantity and culling of infected animals. The biological properties of this pathogenic alga, the laboratory methods available for its isolation and identification, the pathological and clinical features of this form of mastitis, and the principles of its control are reviewed in this paper.  相似文献   

16.
The aim of the present study was to determine the concentration of serum amyloid A (SAA) and the activity of ceruloplasmin (Cp) in milk from cows with subclinical mastitis caused by different pathogens. Eighty-four milk samples from cows with subclinical mastitis and fourteen milk samples from healthy cows were examined. SAA concentration was determined using the commercial ELISA kit (Tridelta Development Ltd., Greystones, Wicklow, Ireland). Cp activity was assessed spectrophotometrically, using the Rice method. The results reveal that the concentration of SAA (with exception of CNS) and activity of Cp in cow milk can be regarded as markers of subclinical mastitis, irrespective of the microorganism inducing the disease. In conclusion, measurement of SAA and Cp in milk samples could be a useful method in diagnosing subclinical mastitis in cows, but the method should be adapted for field use.  相似文献   

17.
奶牛急性乳房炎病原菌的分离与鉴定   总被引:2,自引:0,他引:2  
[目的]为了掌握奶牛急性乳房炎致病菌的种类.[方法]通过采集病牛乳汁样品3份,分别对其病原茵进行分离与鉴定.检测[结果]表明:检出4种共13株细菌,其中致病性金黄色葡萄球菌6株;停乳链球菌5株;大肠埃希茵1株,乳房链球茵1株.[结论]该场奶牛的急性乳房炎是由致病性金黄色葡萄球菌、停乳链球菌、乳房链球菌和大肠杆菌共同引起...  相似文献   

18.
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   

19.
The number of somatic cells and the isolation of the causative agents of mastitis in quarter, composite, bucket, and bulk tank samples of cow's milk was determined four times during a six-month period. The number of somatic cells in milk samples indicated a degree of mastitis infection and was influenced neither by the year season nor by the length of lactation. At a repeated examination of 28 dairy cows an increased number of somatic cells in milk was found once in 68 udder quarters and with three successive samplings only in 21 quarters. The etiological agents of mastitis were detected once in 31 quarters and three times in succession only in five quarters. The number of cows positive by the number of cells in quarter samples of milk increased from 52.9-58.8% at a single examination to as much as 100% at four examinations. The etiological agents of mastitis were isolated in a single examination in 17.6% of cows and at four examinations in 58.8% of cows. The composite and bucket samples of milk containing 200 to 300 thousand cells per ml are recommended to be considered as mastitis-positive: in 68 to 78% they came from cows having more than 500 thousand cells per ml at least in one quarter sample. The number of cells in a bulk sample was in correlation with the percentage of cows having a positive NK-test (similar to CMT) and positive isolation of S. agalactiae from quarter milk samples.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
Bovine mastitis due to Prototheca zopfii leads to reduced milk production and is difficult to cure. Therefore, prevention is the best approach and this is best achieved through the use of effective disinfectants. The aim of this study was to evaluate the in vitro algaecide efficacy of conventional disinfectants against strains of P. zopfii genotype 1 and 2. The minimal algaecide concentration (MAC) of alkyldiaminoethylglycine hydrochloride, chlorhexidine, dioxide chlorine, povidone iodine and sodium hypochlorous acid against 10 isolates and the type strain (SAG2063(T)) of P. zopfii genotype 1 as well as 10 isolates and the type strain (SAG2021(T)) of P. zopfii genotype 2 were examined using the micro dilution method. This in vitro study indicated that alkyldiaminoethylglycine hydrochloride, chlorhexidine, povidone iodine and sodium hypochlorous acid, but not dioxide chlorine, are effective against both genotypes of P. zopfii.  相似文献   

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