California Mastitis Research Articles

Virulence Potential of Penicillium Chrysogenum Isolated from Subclinical Bovine Mastitis

The present study aimed to the isolation and identification of Penicillium chrysogenum from subclinical bovine mastitis as well as the evaluation of their potential to produce the main virulence factors by assessing proteinase production, urease production, growth rate at 37 ̊C, and hemolytic activity on Blood agar. One hundred milk samples were assembled from the White Gold village and surrounded outlying farms of Abu-Ghraib, Baghdad province, during the period from November 2018 to March 2019. Each milk sample was tested for California Mastitis (CMT). The results indicated that 85% of the samples gave positive (+ve) results for CMT. Sixty six mycotic isolates were detected, including 31 isolates of Penicillium spp. (46.9%) and 23 isolates of P. chrysogenum (34.8%). All of P. chrysogenum isolates were identified by culturing on Sabouraud Dextrose Agar and Czapek Doxes Agar at 25 ºC for 5-7 days. P. chrysogenum was diagnosed by polymerase chain reaction (PCR) based on the internal transcribed spacer (ITS) region of fungal ribosomal DNA (rDNA). The results of genetic identities showed that this fungus had 94% matching with the reference strain. Also, this study indicated that P. chrysogenum has several virulence factors with the ability of this fungus to degrade both proteins (albumin and casein), hydrolyse urea, and grow ate 37 ̊C, but not to confer hemolytic activity on Blood Agar.

Study of antibiotic susceptibility of Coagulase- Negative staphylococci isolated from bovine mastitis

A total of 141 milk samples were tested belong to 27 cows infected with clinical mastitis and 114 cows were diagnosed with subclinical mastitis after detected their milk samples by California Mastitis and Whiteside tests, samples were collected from different areas of Mosul city. After the first isolation, the biochemical tests were carried out on all isolation. The samples showed 33 (23.40%) isolates of Coagulase-Negative Staphylococci (C-NS). S. chromogenes & S. epidermidis were predominant in clinical mastitis, while in the sub-clinical cases the S. haemolyticus was most frequently in isolation. The sensitivity test was carried out on isolated bacteria. The test results showed that there was absolute resistance to ampicillin and 90.9% for Penicillin-G, while the lowest resistance and highest sensitivity of Chloramphenicol was 27.27%, 57.57%, respectively, as well as, isolated give varying sensitivity and resistance to other antibiotics. The use of antibiotics at random and the non-completion of treatment the animal by the owner lead to produce a normal flora resistant to most common veterinary antibiotics used, which can become a pathogen when conditions are available, this shown by the results of the current study.

Isolation and Identification of Methicilin Resistant Staphylcoccus a ureus (MRSA) from Bovine Mastitic Milk in and around Wolaita Sodo, Southern Ethiopia

In recent years, there has been increased concern about antibiotic resistant strains of Staphylococcus aureus and multiple antibiotic resistant strains have started to emerge. Development of resistance has been attributed to the extensive therapeutic use o f antimicrobials. A cross sectional study was conducted from November 2013 to May 2014 in and around Wolaita Sodo town, Southern Ethiopia, to isolate and identify MRSA and their resistance to different antimicrobials and also identify risk factors associat ed with occurrence of dairy cow mastitis. A total of 257 dairy cows were included during the study period. Total of 1010 quarters were examined to detect clinical and subclinical mastitis by physical examinations of udder and milk and California mastitis T est (CMT), respectively. Milk samples were collected from each of clinically and sub clinically mastitic non - blind quarters of the selected cows for bacterial isolation. The Staphylococcus aureus isolates were tested for anti - microbial susceptibility by di sc diffusion method. The occurence of mastitis was 40.9%. Out of this, 4.66% and 36.18% were clinical and subclinical respectively. The univariate logistic regression showed that among potential risk factors considered from the farm attributes, age, milkin g hygiene, parity, lactation period, farm floor and previous mastitis treatment had significant (p=<0.05) effect on the prevalence of mastitis. The present study showed the resistance of Staphylococcus aureus to penicillin G (100%), cefoxitin (71.8%), amox icillin - clavulinic acid (61.5%), tetracycline (69.2%), streptomycin (66.7%), chloramphenicol (35.9%), sulphamethoxazole - trimethoprim (43.6%) and vancomycin (56.4%). In the present observation, 28 (71.8 %) Staphylococcus aureus isolates not only showed MRSA but also multidrug resistance (MRSA). The present study emphasizes the importance of MRSA on dairy farms in and around Wolaita Sodo, Southern Ethiopia. The development of antimicrobial resistance is nearly always as a result of repeated therapeutic and/or indiscriminate use of them. Regular antimicrobial sensitivity testing helps to select effective antibiotics and to reduce the problems of drug resistance development towards commonly used antibiotics.

Cross-sectional study on bovine mastitis and its associated risk factors in Ambo district of West Shewa zone, Oromia, Ethiopia.

Aim:A cross-sectional study was conducted to estimate the prevalence and associated risk factors of mastitis in dairy cows.Materials and Methods:A total of 302 dairy cows were selected from all volunteer dairy farms in Ambo district of West Shewa Zone, Oromia region. Thorough clinical examination was made on all lactating cows for evidence of signs of clinical mastitis followed by collection of milk sample for examination of gross changes of milk secretion and California mastitis test.Result:About 126 (41.7%) cows had mastitis, of which 9.9% (30/302) were clinical and 32.8% (96/302) were subclinical mastitis cases. The quarter level prevalence was 44.4% (536/1208), comprising 9.3% (112/1208), clinical and 32.8% (396/1208) subclinical forms of mastitis. In addition, 5.5% (66/1208) of teats were found to be blind on the clinical examination of udder and teat. The Chi-square analysis of intrinsic risk factors revealed significantly (p<0.05) higher prevalence of mastitis in crossbred cattle (47.2%) than indigenous (15.4%), in cattle above 7 years (75%) than less than 2-6 years of age (28%) and cows given more than 4 calves (81.3%) than those with less than 4 calves (31.1%) irrespective to their lactation stage. There was also significantly (p<0.05) higher mastitis prevalence in larger (46.6%) than smaller herds (24.2%) and among the farming systems in semi-intensive (47.1%) and intensive (42.3%) than extensive (8.1%) management system.Conclusion:This study indicated a higher prevalence of mastitis linked with several risk factors. Thus, early diagnosis and regular screening of cows for subclinical mastitis together with proper therapeutic management of clinical cases are of paramount importance. Moreover, control and prevention strategies should be designed and implemented with great emphasis given to risk factors to reduce bovine mastitis and its impact on milk production and food security.

Bovine mastitis in selected areas of southern Ethiopia.

A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian. were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.21%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples. Staphylococcus accounted for 39.2%. Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area.

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.

Correlation Between California Mastitis and Wisconsin Mastitis Test Reagents as Used in the Wisconsin Mastitis Test

Correlation Between California Mastitis and Wisconsin Mastitis Test Reagents as Used in the Wisconsin Mastitis Test