Prevalence of clinical and subclinical caprine mastitis of northern region in Bangladesh

Prevalence of Bovine Mastitis and Its Associated Risk Factors among Dairy Cows in Ethiopia during 2005–2022: A Systematic Review and Meta-Analysis

Bovine mastitis remains a major prevalent disease in cattle and places a significant economic burden on the global dairy industry. The goal of this systematic review and meta-analysis was to examine the overall prevalence of mastitis and its associated risk factors among dairy cows. Scientific articles written in English were recovered from PubMed, ScienceDirect, Web of Science, Google Scholar, Cochrane Library, and other sources from Google Engine and University Library Databases. “Prevalence,” “bovine mastitis,” “clinical mastitis,” “subclinical mastitis,” “associated factors,” “dairy cows,” and “Ethiopia” were search terms used for this study. For critical appraisal, PRISMA 2009 was applied. Heterogeneity and publication bias were evaluated using Cochran's Q, inverse variance (I²), and funnel plot asymmetry tests. A random-effects model was used to calculate the pooled burden of mastitis and its associated factors among dairy cows, along with the parallel odds ratio (OR) and 95% confidence interval (CI). A total of 6438 dairy cows were included in the 17 eligible studies for this meta-analysis. The overall pooled prevalence of mastitis among dairy cows in Ethiopia was 43.60% (95% CI: 34.71, 52.49), of which 12.59% (95% CI: 7.18, 18.00) and 32.21% (95% CI: 24.68, 39.74) were clinical and subclinical cases, respectively. Of the regions, the highest and lowest pooled prevalence estimates of mastitis among dairy cows were 49.90% (95% CI: 31.77, 68.03) and 25.09% (95% CI: 3.86, 46.32) in the Oromia and Amhara regions, respectively. The highest pooled prevalence estimate in the study period was recorded between 2017 and 2022, with a pooled prevalence estimate of 46.83% (95% CI: 35.68, 57.97), followed by the study period from 2005 to 2016, with a pooled prevalence estimate of 39.97% (95% CI: 25.50, 54.44). Gram-positive bacteria (84.70%) were the most prevalent mastitis-causing agents compared with Gram-negative bacteria (15.30%). Breed (AOR: 2.17, 95% CI: 1.44, 2.90), lactation stage (AOR: 1.59, 95% CI: 1.04, 2.15), parity (AOR: 3.31, 95% CI: 1.69, 4.94), history of mastitis (AOR: 3.56, 95% CI: 2.40, 4.71), floor type (AOR: 1.59, 95% CI: −0.16, 3.34), and teat injury (AOR: 6.98, 95% CI: 0.33, 13.64) were factors significantly associated with mastitis among dairy cows in Ethiopia. Early diagnosis and proper medication, as well as implementing appropriate prevention and control measures, are necessary for the management of mastitis in dairy cows.

Epidemiology and antibiogram of common mastitis-causing bacteria in Beetal goats

Background and Aim:

Mastitis has been identified as the most prevalent and economically imperative disease among dairy animals. Thus, understanding its common bacterial pathogens and risk factors is necessary to improve udder health at herd, region, or country level. However, scientific research on caprine mastitis, especially on Beetal breed, has remained to be insufficient in Pakistan. Therefore, this study aimed to evaluate the epidemiology and antibiogram assay of common mastitis-causing bacterial agents, that is, Staphylococcus, Streptococcus, and Escherichia coli, in dairy goats.

Materials and Methods:

In total, 500 Beetal goats, irrespective of age and those that were not treated with any kind of antimicrobial agents during the past 120 h, were screened using California Mastitis Test in Pattoki, Kasur District, whereas epidemiological factors were recorded. The milk samples of mastitic goats were then collected and processed using standard methods. Each sample was primarily cultured on nutrient agar. Using a specific medium, each bacterial colony was separated using several streak methods. Six antibiotic disks belonging to different antibiotic groups were used for antibiogram profiling of bacterial isolates. Chi-square test was used to assess the association of baseline characteristics and mastitis occurrence. Meanwhile, multivariable logistic regression (p<0.001) was utilized to determine the risk factors associated with positive and negative dichotomous outcome of mastitis.

Results:

The results revealed that the overall prevalence of goat mastitis was 309 (61.8%), in which 260 (52%) and 49 (9.8%) cases were positive for subclinical mastitis (SCM) and clinical mastitis (CM), respectively. Streptococcus and E. coli were found to be the predominant isolates causing SCM and CM, respectively (p<0.001). It was observed that amoxicillin+clavulanic acid was highly sensitive to isolates of Staphylococcus and Streptococcus and ceftiofur sodium to isolates of Streptococcus and E. coli., while enrofloxacin was found to be sensitive to isolates of Streptococcus and E. coli. Risk factors such as herd structure, deworming, vaccination, presence of ticks, use of teat dip and mineral supplements, feeding type, age, parity, housing, blood in the milk, milk leakage, milk taste, and milk yield were found to have the strongest association with mastitis occurrence, while ease of milking has moderate association.

Conclusion:

In the area examined, cases of SCM were found to be higher compared with that of CM, and ceftiofur sodium has been identified as the preferred treatment in both clinical and subclinical forms of caprine mastitis in Beetal goats. Risk factors for mastitis that was identified in this study can form the basis for the creation of an udder health control program specific for dairy goats. We hope our findings could raise awareness of the risk factors and treatment approaches for common mastitis-causing bacterial agents.

β-lactam resistance in bacteria associated with subclinical mastitis in goats in Thika Subcounty, Kenya

AIM

This study determined the resistance pattern to β-lactam antibiotics of bacteria isolated from goats with subclinical mastitis in Thika subcounty, Kenya. We also administered a questionnaire to assess the risk factors associated with the occurrence of resistance to commonly used antibiotics.

MATERIALS AND METHODS

We collected milk samples from 110 lactating dairy goats in Thika subcounty to screen for subclinical mastitis using the California mastitis test. Bacterial isolation and identification were performed according to colony morphology, the hemolytic pattern on sheep blood agar, lactose fermentation on MacConkey plates, Gram staining, and standard biochemical tests. The antibiotic susceptibility of the isolates was determined by the agar disk diffusion method using penicillin G, cephalexin, cefoxitin, and cefotaxime antibiotic disks. The double-disk synergy test using amoxicillin-clavulanic acid was employed as a confirmatory test for extended-spectrum β-lactamase (ESBL) production. Fisher's exact test was used to determine the risk factors associated with the occurrence of antibiotic resistance (p≤0.05 was considered significant).

RESULTS

Of the 110 dairy goats sampled, 72.7% (80) were positive for subclinical mastitis. Isolation and identification of the bacteria from the positive samples yielded 149 bacteria isolates, including Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter spp., Yersinia spp., coagulase-negative staphylococci, and Escherichia coli. A high percentage (76.5%, 114/149) of the bacterial isolates was resistant to at least one of the tested antibiotics. At least 56/106 isolates (52.8%) showing cross-resistance to the β-lactam antibiotics were resistant to all four of the tested antibiotics, while only one isolate was resistant to three antibiotics (penicillin G, cephalexin, and cefoxitin). The double-disk synergy test confirmed that none of the isolates possessed ESBLs. Pre- and post-milking practices (p=0.0336) were found to be significantly associated with the occurrence of antibiotic resistance.

CONCLUSION

A large proportion of the goats in our study cohort were infected with β-lactam-resistant bacteria associated with subclinical mastitis. Because the identified bacteria are of zoonotic importance, further studies should be undertaken to determine the transmission dynamics between humans and livestock and to identify novel intervention strategies.

Study on prevalence and bacterial etiology of mastitis, and effects of subclinical mastitis and stage of lactation on SCC in dairy goats in Egypt

In Egypt, inadequate information on prevalence and epidemiology of caprine mastitis is available. This study was designed to investigate prevalence and etiological agents of caprine mastitis and assess the efficacy of somatic cell count (SCC) as marker of subclinical mastitis (SCM) in dairy goats. This study was carried out on 249 randomly selected lactating goats in different lactation stages and examined clinically. Of these animals, 477 milk samples were aseptically collected and screened for bacterial carriage. SCC was assessed in 234 apparently normal milk samples, and SCC ≥ 10⁶ cells/ml was indicator for SCM. Prevalence of clinical mastitis (CM) was 33.73% and 16.87% at animal and udder-half levels, respectively. SCM was 52.56% in the apparently healthy halves. Culture results proved single infection in 49.69% of samples, mixed infection in 23.9% of samples, and 26.41% of samples were negative. Coagulase negative staphylococci (CNS) were the most predominant bacteria (58.75%), then Staphylococcus aureus (S. aureus) (24.375%), and Streptococci (1.875%) were the least. No significant difference was recorded between mean of SCC in bacteriologically positive and negative samples, neither in those with SCC ≤ 10⁶ nor with SCC ≥ 10⁶ cells/ml both in middle and late lactation stages. Besides, the percentage of animals harboring SCC ≥ 10⁶ cells/ml and negative for bacteriology in late lactation stage was 3 times (28.57%) more than in midlactation (9.3%). We can assume that SCC is not proper indicator for intra-mammary inflammation (IMI) in goats, and bacteriological examination remains more efficient, despites being time consuming and expensive.

Study on prevalence, clinical presentation, and associated bacterial pathogens of goat mastitis in Bauchi, Plateau, and Edo states, Nigeria

Aim:

This study aimed to estimate the prevalence and clinical presentations of different forms of mastitis and mastitis-causing pathogens in lactating goats in Bauchi, Plateau, and Edo states, Nigeria.

Materials and Methods:

A total of 500 quarters from 250 lactating goats of Red Sokoto and West African Dwarf breeds during the lactation period were clinically examined. Clinical mastitis was detected by gross signs of udder infection during physical examination and abnormal milk, whereas subclinical mastitis (SCM) was recognized using California mastitis test. The bacterial pathogens were identified by morphology, hemolysis, gram staining, and biochemical tests such as catalase, oxidase, coagulase, reaction on sulfite, indole, and motile medium, and fermentation of sugars.

Results:

The overall prevalence of mastitis in goats was found to be 101 (40.4%), of which 8% (20/250) were clinical, and 32.4% (81/250) were SCM cases. The quarter level prevalence was 29.4% (145/493), comprising 5.9% (29/493) clinical and 23.2% (116/493) subclinical forms of mastitis. In addition, 1.4% (7/500) of teats were found to be blind on the clinical examination of the udder and teat. Several regional inflammatory reactions and abnormalities in milk were found in 69% and 100% of the cases, respectively. Moreover, some indications of generalized signs such as fever, reduction in appetite, increase in respiration, and pulse rate per minute were recorded in 100%, 75%, 85% and 80% of the cases, respectively. The predominant bacterial isolates recovered were Staphylococcus aureus (20.0%), followed by Escherichia coli (15.5%) and Streptococcus agalactiae (11.0%), and the least isolated microorganisms (≤6%) were bacteria of different species including Staphylococcus auricularis, Staphylococcus caprae, Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus hyicus, Staphylococcus xylosus, Staphylococcus lentus, Streptococcus dysgalactiae, Streptococcus pluranimalium, Streptococcus uberis, Streptococcus pneumoniae, Streptococcus ruminatorum, Streptococcus suis, Micrococcus luteus, Enterobacter cloacae, Proteus vulgaris, Klebsiella oxytoca, Klebsiella pneumoniae, Morganella morganii, Salmonella Typhimurium, Citrobacter freundii, Pseudomonas aeruginosa, Acinetobacter rudis, Acinetobacter haemolyticus, and Bacillus cereus.

Conclusion:

Mastitis continues to be recognized as one of the important health issues and leads to major economic losses to the dairy goats caused by many bacterial pathogens, and the effective measures need to be taken to control the disease.