White Side Test Research Articles

Clinical and subclinical mastitis in cows

The most important aspects of diagnosis and occurrence of clinical and subclinical mastitis are presented in this paper. Mastitis is inflammation of udders parenchyma characterized by pathological changes, and physical chemical and bacteriological changes of milk. Subclinical mastitis could be diagnosed by direct or indirect somatic cell count (SCC) by California Mastitis test and N-acetyl-B-D-glucosamynidasys test, ELISA and Whiteside test, and also by chloride and bovine serum albumin level, as well as by electric conductivity of milk. Therapy of mastitis is more successful with appropriate information about pathogen, which demands special mediums laboratory conditions and stuff, in order to evaluate antibiotic sensitivity of specific pathogen. In the majority of countries, similar rate of morbidity (about 40%) and infection rate (25%) of dairy cows were reported, regardless of the cause. Prevalence investigations show similarity in the most of the countries. Predominant cause of mastitis is Staphylococcus aureus, followed by Streptococcus agalactiae. Available data show that incidence rate of mastitis caused by E. coli, Pseudomonas aeruginosa, Aerobacter aerogenes and Klebsiella spp. is increasing. Similar data on incidence of mastits and prevalence of specific pathogen were established in our country.

Chronic caprine mastitis in Nigerian goat breeds: microbiological flora and histopathological findings

In a study involving lactating does with normal-sized and enlarged pendulous udders, 85.5% of milk samples obtained from does with unilateral udder enlargement and 84.8% of samples from bilaterally enlarged udders indicated the presence of intramammary inflammation based on results of the modified Whiteside test. In contrast, only 47.6% of milk samples obtained from normal-sized udders showed evidence of intramammary inflammation. Bacterial cultures were performed on all milk samples which showed evidence of intramammary inflammation. 16 species of bacteria and other microorganisms were cultured from these samples. Bilaterally enlarged udders collectively yielded 13 different microbial isolates, while unilaterally enlarged udders yielded 11, and normal-sized udders yielded 9. The most frequent isolates in all groups were Staphylococcus spp. and Corynebacterium spp. On histopathologic examination, severe pathological changes in the teat and udder tissues of enlarged pendulous udders were observed. Lesions in parenchymatous tissues showed mild to severe inflammation with involution of the parenchyma of glands. This led to shrinkage of the alveoli and in severe cases, their complete disappearance and replacement by fibrous connective tissue which was observed to have a high degree of proliferation. Sections of non-pendulous udder tissue showed proper arrangement of alveoli with hypertrophic epithelial cells, indicating active secretory activity. The results provide some definitive evidence that enlarged pendulous udder development in some Nigerian breeds of goats is not spontaneous but occurs largely as a result of incursion of the mammary glands by pathogenic organisms which may cause mastitis resulting in progressive dysfunction of mammary tissue. In chronic cases, there is severe atrophy of glandular tissue leading to fibrosis.

Estudo do leite de éguas sadias ou portadoras de mastite subclínica, pelo teste de Whiteside, análise microbiológica e contagem de células somáticas

To identify the bacterial population in the milk of healthy mares and with subclinical mastitis, samples (10 to 15 ml) of 38 animals were collected, homogenized and examined using the Whiteside test. The results were negative. The microbiological culture was carried out in 10% agar bovine serum and in agar MacConkey. Both exams revealed the presence of Staphylococcus spp. and Streptococcus spp., predominantly. The somatic cell counts (SCC) was performed in individual samples of each teat and showed a number higher than 500,000 cels/ml of milk in only 9.3% of the 73 samples examined. These results obtained suggest that new researches should be done aiming the standardization of the somatic cell in equine milk.

California Mastitis Test and Whiteside Test in diagnosis of subclinical mastitis of dairy ewes

One thousand and eighty four milk samples from clinically healthy mammary glands of dairy ewes were collected and examined. Bacteriological examination, somatic cell counting, California Mastitis Test and Whiteside Test were undertaken in all samples. Score “1” for California Mastitis Test and score “1 + ” for Whiteside Test are recommended as threshold values for subclinical mastitis, offering at least 93% accuracy of the diagnostic methods.

A field investigation of subclinical mastitis in sheep in southern England

The prevalence, aetiology and epidemiological features of subclinical mastitis were investigated in 358 lowland ewes in seven flocks in southern England. Milk samples (2092) were collected at 3-weekly intervals; those which were both bacteriologically and Whiteside test positive were deemed to have originated from glands with subclinical mastitis. The period prevalence of subclinical mastitis was 11.7% and the prevalence remained relatively constant over the course of lactation (5.5–7.0%). The predominant bacterial isolates from 48 glands with subclinical mastitis were streptococci (42%), coagulase-negative staphylococci (33%), Pasteurella haemolytica (17%) and Staphylococcus aureus (8%). Coagulase-negative staphylococci were the predominant isolates (53%) from samples which did not show a positive Whiteside test result. The prevalence of subclinical mastitis increased with age of ewe but was not influenced by the presence of teat lesions. There was a significant association between the development of clinical mastitis (26 glands) and antecedent subclinical mastitis caused by the same organism (10 glands).

Determination of NA-Gase activity in milk for diagnosis of subclinical caprine mastitis

Two goat herds were examined to determine the prevalence and causes of subclinical mastitis and to assess the value of some laboratory tests currently used as aids in the diagnosis of caprine mastitis. Due to large variation in mean cell count, the Whiteside test and California mastitis test were unreliable in diagnosis of caprine mastitis. N-acetyl-β-D-glucosaminidase (NA-Gase) activity in the milk was a sensitive method in detecting subclinical mastitis in goats. In 381 samples from mammary gland halves of 191 goats, the prevalence of infection in the two herds ranged from 13.0% to 20.0%. Organisms isolated were coagulase-negative staphylococci 54.2%, coagulase-positive staphylococci 20.3%, alpha-haemolytic streptococci 2.0%, Pasteurella haemolytica biotype A 5.0%, Mycoplasma agalactiae 6.0% and Escherichia coli 4.0%.

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.

Screening tests for abnormal milk and physical examination of the udder

Many tests have been described for use in detecting abnormal milk. These include: black plate or strip cup, catalase test, (modified) Whiteside test, serum albumin, milk chloride, electrical conductivity, California Mastitis Test (CMT), Wisconsin Mastitis Test (WMT), Direct Microscopic Somatic Cell Count (DMSCC) and Electronic Somatic Cell Counts (ESCC). In summary, the black plate is still a useful tool for the examination of lactating cows to detect clinical mastitis.
 The CMT Test is a useful cowside test for detecting subclinical infections.
 ESCC provides useful information for assessing the prevalence of subclinical infection and for regular evaluation of mastitis control practices.
 Examination of the udder may be indicated. Udder palpation is not as important in the current scheme of management of cows as it may have been in the past but could still provide useful additional indications for culling decisions.
 Teat end lesions may be reduced by avoiding chemical irritation and faulty machine function. However, teat end appearance may be related to high production and, depending on degree, is not always an indication of unusual trauma.

The New South Wales mastitis control program. 1. Field aspects and their effect on clinical and subclinical mastitis.

A mastitis control program based on teat dipping and dry cow therapy was evaluated in 35 herds over a 3 year period. The incidence of subclinical mastitis as detected by the Rapid Mastitis Test (RMT) fell from 34% to 12% quarters positive, a reduction of 65%. Clinical mastitis was reduced from 37 clinical cases per 100 cows in the first 3 month period to 12 clinical cases per 100 cows in the last 3 month period, a reduction of 68%. Variations in response to the program in the reduction of subclinical and clinical mastitis are discussed and the results compared with similar trials conducted overseas. The Modified Whiteside Test was used on bulk milk samples from the control herds and these results were significantly correlated with the prevalence of subclinical mastitis assessed by RMT individual quarters.

COLLABORATIVE STUDY OF SOME SCREENING TESTS FOR DETECTION OF ABNORMAL MILK

The California Mastitis Test, Modified Whiteside Test, Wisconsin Mastitis Test, tube Catalase Test, Milk Gel Index, and Direct Microscopic Somatic Cell Count (NMC Method) were done according to a detailed protocol in five laboratories. Each laboratory tested about 250 bulk tank milk samples in blind duplicate. Screening tests were compared at various critical scores with respect to their identification of milk samples with cell concentration above (positive) and below (negative) 1.0 and 1.5 million/ml. The percent of positive samples correctly identified is the Utility of the screening test; the percent of negative samples mis-identified is the Cost.At the 1.5 million cells per milliliter limit, and using U.S.P.H.S. recommended critical scores, the mean Cost/Utility estimates were: CMT 68/98, MWT 64/97, WMT 13/84, and CAT 38/94. Lowering the critical score for WMT to > 20 increased its Utility to an acceptable 89% at 17% Cost. At the 1.0 million/ml cell concentration limit the ranking of tests did not change materially. Laboratories varied widely in Cost of screening with all tests, and, particularly for subjectively-scored tests, in the critical score required for equivalent Utility. In all comparisons, the MGI was the test of choice, with the WMT ranking next.

The Effect of Infusion of Sodium Cloxacillin in all Infected Quarters of Lactating Cows in Sixteen Herds

SUMMARY All the infected lactating quarters in sixteen herds were given one of four different intramammary cloxacillin treatments. Each quarter was infused three times at 48-hour intervals with either 0·2 g or 0·6 g doses of sodium cloxacillin in either slow or fast release bases. The four preparations eliminated between 60 and 75 per cent of the 321 infections treated, including all the Str . agalactiae and almost all the Str . dysgalactiae infections. Against Staph . aureus infections, although there was no difference in response between the two dose levels, the slow release preparations were significantly ( P Str . uberis infections there was some indication of a dose effect but this was not significant. Linear regressions relating the percentage response to therapy of the staphylococcal infections with various independent characteristics of the treated cows indicated that staphylococcal infections are less likely to respond if they occur in older cows, in cows with several infected quarters, in cows treated in early lactation or when the Whiteside test scores are high. These relationships explain only some of the considerable differences observed between herds in the proportion of staphylococcal infections responding to therapy.

EVALUATION OF CERTAIN MASTITIS DETECTION TESTS

A curvillinear regression resulted when the Feulgen-DNA test scores were plotted against the average concentration of leucocytes. Application of a logarithmic transformation to the average test data resulted in a linear correlation which slightly raised the correlation between the Feulgen-DNA Test and the leucocyte count. But, the application of a sample per cow transformation to the average test data from each of 30 representative cows, resulted in an approximate linear relationship and in significant correlations between the Feulgen, California, and Whiteside tests and the leucocyte count. Correlations in descending order were Feulgen> California> Modified Whiteside Test with respect to the leucocyte count.

Studies on the mechanism of the whiteside mastitis test reaction

SummaryThe contribution of certain components of leucocytes and milk to the viscosity and precipitate which develop in the Whiteside mastitis test was studied to obtain information on the mechanism of the reaction. The viscosity obtained in the Whiteside test reaction was considerably less than that in the California mastitis test reaction and the Whiteside test was found to be more dependent on precipitation than increased viscosity.Leucocyte nuclei were mainly responsible for the formation of the precipitate in the Whiteside reaction and CaCl2 dispersed the precipitate formed by the leucocyte nuclei into small clumps. Leucocyte protein and fibrinogen increased the amount of precipitate formed by the leucocyte nuclei. Fat globules also increased the amount of precipitate, probably by being trapped in the precipitate.The addition of non-gelable or gelable nuclei resulted in the formation of similar amounts of precipitate in the modified Whiteside reaction. Furthermore, storage of milk for 5 days did not decrease the amount of precipitate formed, indicating that the DNA-protein complex of the leucocyte nuclei need not be present in the native form to contribute to the precipitate in this reaction.

Detection of Non-tuberculous mycobacteria hsp65 in some ruminant’s subclinical mastitis milk and rheumatoid arthritis patient’s blood

The main aim of this study was to detect non-tuberculous mycobacteria hsp65 in animal’s subclinical mastitis milk and Rheumatoid arthritis patients blood. Modified White Side Test (MWT) was used as a preliminary screening test for subclinical mastitis in 70 cows ,50 ewes and 30 goats milk samples. The results of this test revealed that 58(82.9%), 38(76%) and (46.7%) of cows, ewes and goats milk samples respectively were positive with significant difference(P<0.05). Statistically significant (P<0.05) varying score of positivity was observed by this test, as a follow; score (+++) in cows (37.93%) and ewes (28.9%) milk samples only , score (++) in all cows, ewes and goats milk samples at different percentage(18.96,21.1 and14.3%, respectively) and score (+) in cows (43.11%,), ewes (50%) and goats(85.7%) milk samples. Molecular detection of non-tuberculous mycobacteria (NTM)16SrRNA gene in Milk samples revealed that 3(6%) and 11 (22%) cows and ewes milk samples respectively showed positive results with significant difference(P<0.05). The NTM hsp65 gene (441 bp) was detected in 50(71.4%) and10 (20%) milk samples of cows and ewes respectively with significant difference(P<0.05).This gene also detected in 3) 33.3% ( rheumatoid arthritis patients blood samples with an overall percentage of 7.5% and negative results for this genewas observed in non rheumatoid arthritis patients blood samples with significant difference(P<0.05). The hsp65 gen sequencing results confirmed high sequence similarity (99%) of the current hsp65 (441 bp ) sequences with Mycobacterium avium retrieved DNAsequences (GenBank acc. NZ_CP009360.4).

Evaluation of Seven Procedures for Detection of Abnormal Milk Due to Mastitis

Five screening tests (California Mastitis Test, Catalase Test, Milk Quality Test, Modified Whiteside Test, and Wisconsin Mastitis Test) and two confirmatory procedures (Direct Microscopic Somatic Cell Count and Electronic Somatic Cell Count) for testing for abnormal milk due to mastitis were evaluated for relative precision when used to test 48-hr bulk-tank milk within 6 hr after pickup, as well as 24 and 48 hr later. Because of the lack of screening test results in high- and low-count ranges, only the Wisconsin and the Catalase tests could be evaluated by statistical techniques; these procedures had replicate standard deviations of 0.73 and 2.91, respectively. of the five screening test procedures, the Wisconsin Mastitis Test gave the best indication of somatic cell numbers. A comparison of the confirmatory procedures showed the Electronic Somatic Cell Count to be more precise, with approximately one-fourth the replicate long standard deviation of the direct Microscopic Somatic Cell Count (0.012 vs. 0.047). Linear correlation coefficients of the Electronic, Wisconsin, and Catalase results with Direct Microscopic were 0.97, 0.89, and 0.70, respectively, for milks tested 24 hr after pickup. Somatic cell numbers as measured by the Electronic, Direct Microscopic, and Wisconsin procedures, but not the Catalase Test, were significantly different (α = 0.05) at each time interval tested. The effect of non-pipeline and pipeline milk filters used by milk produces on somatic cell numbers was also determined. The most efficient nonpipeline filters reduced the somatic cell count 2.5%, whereas there was no significant change in cell numbers in milk filtered by pipeline filters.

THE SPOKANE CITY HEALTH DEPARTMENT MASTITIS CONTROL PROGRAM

The City of Spokane Health Department was asked by the U. S. Public Health Service to study and instigate a practical abnormal milk control program in 1962. From May until November 1962 composite bulk tank samples were tested using the Modified Whiteside Test. Some abnormal milk appeared in 42% of the bulk tank samples. With this information, a meeting was called which included personnel from the U. S. Public Health Service, State Department of Health, State Department of Agriculture, Idaho Health Department, Extension Service, Dairy Industry, the Dairy Science Departments of Washington State University and the University of Idaho. A program was started using five committees recommended by the National Mastitis Council and a steering committee. The Direct Microscopic Leucocyte Count (DMLC) was adopted for official use and an educational program was started.In April 1965, it was agreed that enforcement was needed to bring the leucocyte level below 1,000,000 per ml. After a few suspensions, the results were amazing, dropping from 22% to 1% of the producers continually with over a million per ml of milk.In April 1966, the City adopted the 1965 U. S. Public Health Service Grade “A” Milk Ordinance and included an Abnormal Milk Section with 800,000 leucocytes/ml as a limit and using the 3 out of 5 method of suspension. At present, the DMLC is the official method and the industry is using the Wisconsin Mastitis Test monthly on all their producers.The program has been very successful because of the cooperation of the milk industry, machine installers, Extension Service, Dairy Science Departments and Health Departments. It will be possible in the future to meet the 500,000 leucocytes per ml limit.

The Relationship Between the California Mastitis Test, Whiteside Test, Brabant Mastitis Reaction, Catalase Test, and Direct Cell Counting of Milk

The aim of this work was to study the relationship between the reactions obtained by indirect methods of testing milk samples and the cell content, determined by direct cell counting after Prescott & Breed (1910). The indirect tests used were the California Mastitis Test (CMT), Whiteside Test (WsT), Brabant Mastitis Reaction (BMR), and the Catalase Test (CT). The results of the investigations are summarized below. Samples with cell values lying within fixed limits do not neces¬sarily conform to particular indirect test reactions. All four indirect tests have wide ranges of variation of cell level within a given reaction with considerable overlapping between reac¬tions. The standard deviation for cell levels within a given reaction is large, although this can be partly explained by the fact that the cell values are estimated rather than real. Correction for this produces only an insignificant decrease, however. The coefficient of correlation is a little higher for the correlation CMT—CC than for the other indirect tests and CC. When sample groups with different mean cell levels (calculated from the whole material) are compared, the variation ranges (dif¬ference between the largest and the smallest observation) and standard deviations arc generally the same for the different CMT reactions. However, the mean cell values, for different reactions lie at higher levels when the mean cell content of the whole material is higher. Similarly they are lower when the mean of the whole material is lower. This is, however, not true for 0 reactions. The mean cell values for CMT 4- and for 4- 4- reactions varied considerably in different herds. It was not considered acceptable, for any of the four indirect tests, to substitute reactions by average cell values, either to determine the mean cell value or to decide whether a sample is inacceptable, if this means that the sample has a cell content above a certain value. Negative and 4- reactions for CMT and WsT could possibly be replaced by a mean cell level, since the range of variation is not so wide here and the majority of samples giving these reactions contain less than 3xl05 cells per ml. The possibility exists of combining indirect tests and direct cell counting to examine milk samples, so that samples with low reactions could be passed, while those with higher reactions would be examined by cell counting. The indirect tests differentiate milk at different cell levels. The possibility of using a particular indirect test depends on the cell level to be examined and on the degree of accuracy required.

Comparison of Results of Mastitis-Screening Tests of Milk from Individual and Pooled Cow Quarters

Results from California Mastitis (CMT), Milk Quality, Modified Catalase, and Modified Whiteside tests were compared with Direct Microscopic Leucocyte Count DMLC) on 525 aseptically collected milk samples from 21 dairy farms in three mid-western states. All samples were tested within 3–5 hr after collection and retested after 48-hr refrigeration at 1.7C.The agreement of the various screening tests with DMLC on 420 quarter samples ranged from 84 to 86%; whereas, on 105 pooled quarter samples, the agreement ranged from 79 to 90%. If screening test results were identified as either negative (negative and trace test scores) or positive (1+, 2+, 3+, or equivalent in catalase activity or DMLC), test scores of all screening tests were identical on 75 and 68% of the milk samples from individual and pooled quarters, respectively. Significant differences between test scores on milk samples from both individual and pooled quarters before and after storage were found only with the CMT test. Milking practices were compared with screening test results, and it was found that failure to sanitize teat-cup liners significantly increased levels of leucocytes in milk.

SURVEY OF ABNORMAL MILK PROGRAMS ADMINISTERED BY STATE REGULATORY AGENCIES

SummaryThrough survey questionnaires, information was obtained about the abnormal milk control programs administered by state regulatory agencies. Responses were received from dairy regulatory officials in 49 states. A majority (67%) of the states did not have a designated abnormal milk regulatory program at the time of this survey, but many were in the process of developing such programs. More concern was evident for the control of abnormal milk in the Grade A supply than for the manufacturing supply.The tests most widely reported for detecting abnormal milk (in order of prominence) were: microscopic leucocyte count, California mastitis test, modified Whiteside test, catalase test, and Wisconsin mastitis test. Standards based on leucocyte counts of 500,000 or 1,000,000/ml were reported by 13 states. Approximately 70% of the responding states indicated that their programs followed the recommendations of the National Mastitis Council; however, others (30%) indicated further studies would be made before abnormal milk regulations could be promulgated.

DETECTION EFFICIENCY OF MASTITIS SCREENING TESTS

SummaryA comparison of the detection efficiency of five screening tests for mastitis was made by correlating test results with results of a specific laboratory standard based on a direct leukocyte count and/or the culturing of infectious organisms on the same samples of milk. Since the screening tests are “indirect” or non-specific in nature, the measure of effectiveness took into consideration not only the per cent detected as compared to that detected by the laboratory method, but also the per cent of readings which were false positives. Both per cent detection and per cent false positives increased with increasing test sensitivity. The level of detection at which the per cent of false positives began to increase rapidly was chosen as the optimum efficiency for each type of test. This optimum efficiency correlated with the presence of mastitis as follows: California Mastitis Test 69.5%; Whiteside Test 65.5%; Filter Disk Test 45.0%; Catalase Test 43.8%; Strip Plate Test 4.7%.