Acute phase proteins in the diagnosis of bovine subclinical mastitis

Background: The California mastitis test (CMT) and somatic cell count (SCC) are commonly used for diagnosis of subclinical mastitis in cattle. Acute phase proteins (APPs), as alternative biomarkers of mastitis, may increase in concentration in the absence of macroscopic changes in the milk, or may precede the onset of clinical signs. Objective: The aim of this study was to compare the accuracy of APPs measured in milk and in serum with bacterial culture for the diagnosis of bovine subclinical mastitis. Methods: One hundred and seventy‐five Holstein cows were randomly selected from 7 dairy farms. Quarter milk and serum samples were taken from all cows. Milk samples were analyzed using a CMT and SCC, and for haptoglobin (MHp) and amyloid A (MAA) concentrations, and were also submitted for bacterial culture. Serum samples obtained concurrently were analyzed for haptoglobin (SHp) and amyloid A (SAA). Two‐sample Wilcoxon (Mann–Whitney) test was used to compare SCC, MAA, MHp, SAA, and SHp concentrations between culture‐positive and culture‐negative animals. Receiver‐operating characteristic analysis was used to assess the performance of each test using bacterial culture as the reference method. Results: MAA concentration was the most accurate of the 5 tests, with a sensitivity of 90.6% and specificity of 98.3% at concentrations >16.4 mg/L. MAA and MHp had significantly larger areas under the curve than the respective serum proteins, SAA and SHp. Conclusions: The results suggest that measuring haptoglobin and amyloid A in milk is more accurate than serum analysis for the diagnosis of subclinical mastitis in Holstein cows.     

Factors for the genesis of bovine subclinical mastitis

The infection risk of the bovine mammary gland is determined by susceptibility of the cow and contamination and invasion by mastitis pathogens. Genetic (e.g. yield) and lactational physiologic (e.g. stage of lactation) factors support the genesis of subclinical mastitis. This paper considers new data on cow individual and milking related influences on defence mechanisms in the teat end tissue acting in prevention of penetration through the teat canal by mastitis pathogens.     

Immunotherapeutic potential of Ocimum sanctum (L) in bovine subclinical mastitis

Immunotherapeutic potential of aqueous extract of Ocimum sanctum (O. sanctum) leaf in bovine sub-clinical mastitis (SCM) was investigated. Somatic cell count (SCC), total bacterial count (TBC), milk differential leukocyte count (DLC), phagocytic activity and Phagocytic index and leukocyte lysosomal enzymes like myeloperoxidase and acid phosphatase content were evaluated after intramammary infusion of aqueous leaf extract of O. sanctum. The results revealed that the aqueous extract of O. sanctum treatment reduced the TBC and increased neutrophil and lymphocyte counts with enhanced phagocytic activity and phagocytic index. Similarly, the lysosomal enzymes contents of the milk polymorphonuclear cells (PMNs) were also enhanced significantly in animals treated with the extract. The results suggest that the crude aqueous extract of O. sanctum (leaf) possesses some biologically active principles that are antibacterial and immunomodulatory in nature. As such, the present wok substantiates the therapeutic use of medicinal herb and also emphasizes on the potential of the commonly available non-toxic substances to enhance the mammary immunity.     

Evaluation of PCR test for detecting major pathogens of bubaline mastitis directly from mastitic milk samples of buffaloes

Present study is aimed to evaluate the PCR test for detecting the major pathogens of bubaline mastitis (BM) directly from the mastitic milk samples of the buffaloes. Cell lysates of the enriched mastitic milk samples were directly used as template DNA in PCR and the reactivity of genus and/or species specific primers against the selected pathogens of BM was tested in individual simplex PCR assays. Out of the 60 mastitic milk samples tested 30 were positive for E. coli, 21 were positive for S. aureus, 4 were positive for S. agalactiae, 9 were positive for S. dysgalactiae and 7 were positive for S. uberis. Certain samples were positive for more than one pathogen thus indicating the mixed infection of the udder. Although certain mastitic milk samples reacted with Staphylococcus genus specific primers, they didn’t react with S. aureus specific primers in PCR, which indicates the implication of other species of Staphylococcus in BM. The processing of mastitic milk samples was also simplified by eliminating the use of expensive reagents. The detection limits of PCR with the cell lysates are sensitive enough for PCR to be used as diagnostic tool for identifying the pathogens of BM.     

The detection of subclinical mastitis in the bactrian camel (Camelus bactrianus) by somatic cell count and California mastitis test

Milk samples (n=160) from 7 clinically healthy bactrian camels were cultured to detect subclinical udder infection. The samples were assessed by the Californian mastitis test (CMT) and somatic cell count (SCC). Bacteria were recovered from 36 (22.5%) of the milk samples. Staphylococcus aureus and coagulase-negative staphylococci (CNS) were the main organisms found.Infected quarters had significantly higher mean values for the SCC (p<0.01) and CMT (p<0.001) than non-infected quarters. All 7 camels were infected with CNS but only 4 with S. aureus. CMT values for S. aureus-infected camels were significantly higher than for those only infected with CNS. The values for SCC and CMT were significantly influenced by the stage of lactation (p<0.05). No significant difference was found from the effect of the quarters. Both SCC and CMT were of value in predicting the infection status of the udder.Abbreviations CMT California mastitis test - SCC somatic cell count - CNS coagulase-negative staphylococci     

An evaluation of a hand-held electrical resistance meter for the diagnosis of bovine subclinical mastitis in late lactation under Australian conditions

OBJECTIVE: To assess the ability of a hand-held device to differentiate between infected and noninfected bovine mammary glands according to the electrical resistance of milk, under Australian conditions. DESIGN: A cross-sectional study. PROCEDURE: Milk samples were collected from 236 quarters of 60 cows selected from a commercial dairy herd with a high prevalence of mastitis. The true infection status of these quarters was determined using bacteriology. Various methods were used in an attempt to relate the electrical resistance of milk from each quarter to the presence or absence of infection in that quarter. RESULTS: Although the electrical resistance of milk from infected quarters was generally lower than that of noninfected quarters, the overlap of readings between the two populations limited the ability of this device to indicate accurately whether a quarter was infected. The use of methods comparing the readings from each of the four quarters of a single cow did not allow the reliable detection of infected cows. CONCLUSION: Although this device may have some practical advantages in comparison with some other methods of diagnosing subclinical mastitis, the predictive value of the method was generally poor.     

Evaluation of PetrifilmsTM as a diagnostic test to detect bovine mastitis organisms in Kenya

The study purpose was to validate Petrifilms^TM (3M Microbiology, 2005) against standard culture methods in the diagnosis of bovine mastitis organisms in Kenya. On 128 smallholder dairy cattle farms in Kenya, between June 21, 2010 and August 31, 2010, milk samples from 269 cows that were positive on California Mastitis Test (CMT) were cultured using standard laboratory culture methods and Petrifilms^TM (Aerobic Count and Coliform Count –3M Microbiology, 2005), and results were compared. Staphylococcus aureus was the most common bacterium isolated (73 % of samples). Clinical mastitis was found in only three cows, and there were only two Gram-negative isolates, making it impossible to examine the agreement between the two tests for Gram-negative- or clinical mastitis samples. The observed agreement between the standard culture and Petrifilm^TM (3M Microbiology, 2005) results for Gram-positive isolates was 85 %, and there was fair agreement beyond that expected due to chance alone, with a kappa (κ) of 0.38. Using culture results as a gold standard, the Petrifilms^TM had a sensitivity of 90 % for Gram-positive samples and specificity of 51 %. With 87 % of CMT-positive samples resulting in Gram-positive pathogens cultured, there was a positive predictive value of 93 % and a negative predictive value of 43 %. Petrifilms^TM should be considered for culture of mastitis organisms in developing countries, especially when Gram-positive bacteria are expected.     

Evaluation of the agar gel immunodiffusion test for diagnosis of subclinical paratuberculosis in cattle

Concurrent bacteriologic culture of feces and agar gel immunodiffusion (AGID) testing was performed on all cows and bred heifers over 14 months old in 10 dairy herds during a 32-month period to determine the effectiveness of the AGID test for the detection of subclinical paratuberculosis. Herds were sampled 5 times and, when possible, culled animals were tested again at slaughter. During 5 herd-wide samplings, Mycobacterium paratuberculosis was isolated from 139 fecal specimens obtained from 109 cattle. Results of the AGID test were simultaneously positive 40 of 139 times (28.8%). Thirty-six of the 109 cattle (33.0%) determined to be infected had a positive AGID test result at some point during the 5 herd-wide samplings. When results of tests performed at time of slaughter were included, 117 cattle were identified as infected by culture methods; 55 of these (47.0%) were AGID test-positive at some point during the study. The upper limit of the maximal false-positive rate for the AGID test was 2.1%. On the basis of colony counts from cultures, subclinically infected cows shedding higher numbers of M paratuberculosis in their feces were more likely to have positive AGID test results (P less than 0.0001). In known infected cattle, neither the culture nor AGID test results were consistently positive on repeated testing. Of 48 official calfhood paratuberculosis vaccinates tested as adults, 3 had positive AGID test results and in 1 of these, M paratuberculosis was also isolated from the feces, indicating that the rate of false-positive AGID test results in calfhood vaccinates is low.     

Prevalence, causes and laboratory diagnosis of subclinical mastitis in the goat

Five goat herds were examined to determine the prevalence and causes of subclinical mastitis and to assess the value of some laboratory tests currently used on milk samples as aids in the diagnosis of caprine mastitis. In the 170 samples taken from the pairs of mammary glands of 85 goats, the prevalence of infection in the different herds ranged from 15 per cent to 79 per cent of halves. Just over one-third (36 per cent) of all halves were infected, the organisms isolated being coagulase-negative staphylococci (80 per cent), coagulase-positive staphylococci (16 per cent), alpha-haemolytic streptococci (2 per cent) and Pasteurella haemolytica (2 per cent). Neither anaerobic organisms nor mycoplasmas were found. Tests confirmed that the coagulase-positive staphylococci were pathogens but that the coagulase-negative staphylococci rarely caused detectable disease in the caprine udder. The large between-herd variation in the geometric mean cell counts of uninfected milk samples means that somatic cell counts, the Whiteside test and the California mastitis test, are unreliable as aids in the diagnosis of caprine mastitis.     

川渝地区奶牛隐性乳房炎调查和主要病原菌分离鉴定及药敏试验

用LMT法对川渝地区134头泌乳奶牛的491个乳区进行隐性乳房炎发病情况调查,并对阳性乳样进行主要病原菌的分离鉴定及药敏试验。结果显示,被检奶牛患隐性乳房炎头阳性率为70.90%,乳区阳性率为35.64%,175份阳性乳样的细菌检出率为90.86%,病原菌单独感染率为10.69%,混合感染率为89.31%;共分离到金黄色葡萄球菌、链球菌和大肠杆菌3种主要病原菌134株,其中金黄色葡萄球菌93株,占分离菌株的69.40%,链球菌34株,占25.37%,大肠杆菌7株,占5.23%;主要病原菌对呋喃妥因、新生霉素、头孢菌素类和喹诺酮类药物敏感性较好,对大多数抗菌药物产生不同程度的耐药性,对青霉素和链霉素则完全不敏感,耐药程度接近100%。     

The Automicrobic System (AMS)--a new test method for the classification and susceptibility testing of bovine mastitis streptococci

In the period of January 1987 to March 1988 15,800 quarter milk samples from cows of Lower Austrian problem herds were collected and 744 streptococci strains isolated. These 744 isolates were identified by means of the AUTO-MICROBIC-SYSTEM (AMS). As comparative methods the test system API 20 STREP as well as the comparison with the agar-diffusion test. Due to AMS 360 (=48.4%) of the 744 isolates examined could be identified as streptococci and referred to following species: 16 (=4.4%) Sc. agalactiae, 205 (=56.9%) Enterococci; 74 (=20.5%) Sc. uberis; 61 (=16.9%) Sc. of the viridans streptococci and 4 (=1.1%) Sc. pneumoniae. Both test systems AMS and API 20 STREP showed a coincidence of 91.6%.     

A field experiment to evaluate a practical hygiene programme for the control of bovine mastitis

Abstract

Extract

The control of the spread of mastitis infection by good hygiene in the milking shed has long been advocated but the methods used have varied in their efficiency and practicability. Moller (1957 Moller, K. 1957. N.Z. vet. J., 5: 79–79. [Taylor &; Francis Online] , [Google Scholar]) reported good results in the control of Streptococcus agalactiae infection when running water was used to wash the udder, and teat cups were dipped in Chlorhexidine solution between cows. However, many farmers find that dipping cups is irksome and, unless it is carefully done, it becomes ineffective.     

Evaluation of the California mastitis test (CMT) reaction in goat milk and its interpretation

For evaluation of different factors regarding CMT results 65 goats were used. Age, milking hygiene and technique of the animals were recorded and the CMT results were evaluated in relation to those parameters. Correlations between CMT results and age as well milking hygiene and -technique respectively were found. Furtheron the CMT was evaluated as indicator for mastitis diagnosis. Therefore clinical examination of the udder, bacteriological examination of milk samples (aseptically collected) and the determination of the somatic cell count were carried out. The results showed that CMT is not specific for infected udder halves. As important udder pathogens staphylococci were found, S. aureus and CNS at the same level. This investigation has shown that CMT can be used as additional diagnostic tool concerning goat mastitis, but it should not be overestimated because of different factors which influence the cell count. For the control of udder health additional diagnostic measures are of utmost necessity.     

冀东地区奶牛隐性乳房炎病原菌的分离鉴定

通过LMT法、乳汁pH检验法和体细胞直接计数等方法相结合,对冀东地区3个大型奶牛场、8个奶牛养殖户选取的1 021头奶牛进行隐性乳房炎流行病学调查与病菌分离鉴定。结果表明,隐性乳房炎发病率为60.63%(619/1021),乳房炎阳性乳样品中细菌分离率达88.21%(546/619)。从543头隐性乳房炎患牛的阳性乳区乳样中分得细菌共4类14种菌82株,其中葡萄球菌36株,占43.90%;链球菌33株,占40.24%;肠杆菌类8株,占9.76%;棒状杆菌5株,占6.10%。冀东地区奶牛隐性乳房炎主要病原菌为金黄色葡萄球菌和无乳链球菌。     

Evaluation of a scheme for predicting the gram-staining reaction of organisms causing bovine mastitis.

The accuracy of a scheme for predicting the gram-staining reaction of organisms causing bovine mastitis in cows with systemic signs of disease (anorexia) was evaluated over 1 year. Criteria for making the predictions included: season of year, stage of lactation, appearance of milk, detection and duration of teat injuries, and milk odor. It was possible to determine the cause by microbiologic culture of specimens from 136 of the 147 cows of the study. Of 78 infections caused by gram-negative (mostly coliform) organisms, 62 (79%) were predicted accurately to be caused by gram-negative organisms. Of 57 infections caused by gram-positive organisms, 45 (79%) were predicted correctly to be caused by gram-positive organisms. Correctly predicted as gram-positive organisms causing infection were: Actinomyces pyogenes in 20 of 21 (95%) cows; Staphylococcus sp in 14 of 22 (64%) cows; Streptococcus sp in 10 of 13 (77%) cows and Bacillus sp in 1 cow. Overall accuracy, in those instances when bacteria were isolated (136 cows), was 78%.