Prevalence Of Subclinical Mastitis Research Articles

Molecular insights into expression and silencing of resistance determinants in Staphylococcus aureus.

This study aimed to investigate the status of antimicrobial-resistant strains of Staphylococcus aureus in Pakistan, their association in terms of co-occurrence with the biofilm-forming genes, resistance profiling and associated discrepancies in diagnostic methods. A total of 384 milk samples from bovine was collected by using convenient sampling technique and were initially screened for subclinical mastitis, further preceded by isolation and confirmation of S. aureus. The S. aureus isolates were subjected to evaluation of antimicrobial resistance by phenotypic identification using Kirby-Bauer disc diffusion method, while the genotypic estimation was done by polymerase chain reaction to declare isolates as methicillin, beta-lactam, vancomycin, tetracycline, and aminoglycoside resistant S. aureus (MRSA, BRSA, VRSA, TRSA, and ARSA), respectively. The current study revealed an overall prevalence of subclinical mastitis and S. aureus to be 59.11% and 46.69%, respectively. On a phenotypic basis, the prevalence of MRSA, BRSA, VRSA, TRSA, and ARSA was found to be 44.33%, 58.49%, 20.75%, 35.84%, and 30.18%, respectively. The results of PCR analysis showed that 46.80% of the tested isolates were declared as MRSA, 37.09% as BRSA, and 36.36% as VRSA, while the occurrence of TRSA and ARSA was observed in 26.31% and 18.75%, respectively. The current study also reported the existence of biofilm-producing genes (icaA and icaD) in 49.06% and 40.57% isolates, respectively. Lastly, this study also reported a high incidence of discrepancies for both genotypic and phenotypic identification methods of resistance evaluation, with the highest discrepancy ratio for the accA-aphD gene, followed by tetK, vanB, blaZ, and mecA genes. The study concluded that different antibiotic resistance strains of S. aureus are prevalent in study districts with high potential to transmit between human populations. The study also determined that there are multiple resistance determinants and mechanisms that are responsible for the silencing and expression of antibiotic resistance genes.

Genotypic insights to Panton-Valentine leukocidin positive methicillin-resistant Staphylococcus aureus isolated from cattle mastitis.

In this research communication we investigate the prevalence and antimicrobial susceptibility of S. aureus harboring virulent genes responsible for mastitis in cattle of Punjab, Pakistan. A total of 690 milk samples were collected from commercial dairy farms for analysis of the prevalence of subclinical and clinical mastitis and isolation of S. aureus. Virulence ability and methicillin resistance in S. aureus (MRSA) was determined by targeting the pvl (the gene for Panton-Valentine leukocidin) and mecA genes, respectively. A total of 175 S. aureus isolates exhibiting prevalence of pvl gene (6.28%) and mecA gene (22.28%) were determined. Antimicrobial susceptibility testing of pvl positive and negative MRSA against different classes of antibiotics revealed 100% resistance against β-lactams while 100% sensitivity towards tylosin and linezolid.

Prevalence and risk factors of subclinical mastitis in goats in western Algeria

Subclinical mastitis (SCM) is a frequent disease in dairy goats that negatively impact milk quality and yield, leading to substantial economic losses. This cross-sectional study was conducted to estimate the prevalence of SCM and its associated risk factors among dairy goats in western Algeria. The study included 22 farms, and data on risk factors were collected using a questionnaire administered to the farmers. A total of 150 goats, with no clinical signs of mastitis, were randomly selected to determine the prevalence of SCM, using the California Mastitis Test. The Generalised Linear Mixed Model was used to identify the risk factors. The estimated prevalence of SCM was 20.7%. The results of the model indicated that the risk of SCM is significantly higher in does that had dirty udders, raised in unclean barns, were multiparous or in the late stage of lactation. Our findings emphasise the importance of appropriate herd management practices in reducing the prevalence of SCM in dairy goat herds.

Breed and non-genetic risk factors associated with the prevalence of subclinical mastitis in livestock systems of Arauca, Colombian orinoquia

ABSTRACT Subclinical Mastitis (SCM) is caused by several factors associated with the interaction of the individual cow, cow management, and the environment. The aim of this study was to assess the breed and non-genetic risk factors on the prevalence of SCM in cows from the dual-purpose livestock system on the floodplain of Arauca, Colombian Orinoquia. Milk samples were taken from the individual mammary quarters of 481 cows representing 28 different farms where the electrical conductivity (EC) test applied. To determine the factors associated with SCM, a multiple logistic regression analysis was used. The response variable was the SCM presence (1), or absence (0) obtained with the EC test. Breed was included as a genetic risk factor, and as non- genetic risk factors: number of cows in production, daily milk production, lactation month, cow age, climatic period, body condition, and calving number. The factors that were significantly associated with the SCM presence were body condition, climatic period, and breed (p < 0.05). Odds ratio (OR) analysis of significant effects indicates that for each unit increase in body condition, the OR of having animals with SCM is reduced by 71%. In the dry period the OR of animals with SCM increases by 150% compared to the rainy period. Composite breeds reduce the OR of SCM animals by 73%, compared with Indicus-predominance animals. In this study, the occurrence of SCM in extensive management systems in Arauca, Colombian Orinoquia, is determined by the risk factors of breed, climatic period, and body condition.

Evaluation of close up antimicrobial therapies for treatment and prevention of subclinical mastitis in the herds with high prevalence of Staphylococcus aureus

This field trial was conducted to evaluate two antibiotics at a close-up period in curing the existing IMI and to prevent new clinical and subclinical Intramammary infection (IMI). Two hundred and twelve Holstein cows were assigned to one of three treatment groups: TYLO, MARB and CONT. Cows in TYLO group received 10 mg/kg Tylosin for three days at the close-up period (21 days before calving), cows in MARB group received single SC injection of 8 mg/kg SC marbofloxacin at the close-up period and cows in CONT group remained untreated. Milk samples were collected for somatic cell count, microbial culture and Total oxidant/antioxidant capacity before drying-off, and 3 and 7days post calving. Antimicrobial susceptibility test and RAPT-PCR were performed on S.aureus isolates. No significant differences were detected in total cure rate within the groups, but S. aureus cure rates in TYLO and MARB were significantly higher than in CONT (74 and 73.5 % Vs 58.1 %). No significant differences in total new IMI were observed. Furthermore, the rate of new S. aureus IMI was higher in both treatment groups than in CONT group. Clinical mastitis rate in TYLO (3.8 %) and MARB (5.8 %) was significantly lower than CONT (11.3 %). Paired S. aureus isolates from dry-off and post-calving have been clustered into 9 different RAPD types (A-I). 8 paired strains collected at dry-off were identical to those at post-calving,and 35 strains had more than 60 % dissimilarity. Administration of Tylosin or Marbofloxacin is not useful in all cases;however, they have the potential to reduce the incidence of post-calving clinical mastitis and improve S.aureus cure rate if used selectively.

Haematological and Metabolic Profile Test of Subclinical Mastitis Affected Cross Bred Cattle

The current research was conducted during May–October, 2023 aimed to assess the haemato-biochemical parameters in cattle affected with S. aureus affected subclinical mastitis. Mastitis in dairy cattle is the persistent, inflammatory reaction of the udder tissue. Financial losses due to mastitis occur in the case of both sub-clinically and clinically affected animals. Sub-clinical mastitis exhibits no clinical signs and mostly remains unnoticed by the farmer and can be detected if specific tests are performed in milk samples. Sub-clinical mastitis has an erosive effect on the economy of dairy farmers as it effect directly on the milk quality and quantity. In India prevalence of sub-clinical mastitis was found to be more in cows when compared to clinical mastitis. Blood samples were collected from the jugular vein of 10 healthy and 10 subclinical mastitis affected cattle. Blood samples were analyzed for Hb, PCV, TEC, TLC, while serum samples were examined for ALT, AST, ALP, Glucose, Total protein, Albumin, Cholesterol and Calcium. Haematology report showed significantly (p&lt;0.01) decrease in Hb, PCV and TEC in subclinical affected cattle when compared to healthy animals. TLC was significantly increased in (p&lt;0.01) subclinical affected animal than healthy animal. Biochemical estimate revealed significantly (p&lt;0.05) higher average values of AST, ALP and Ca in subclinical mastitis affected animals compared to healthy animals. Glucose, total protein, albumin, cholesterol and ALT levels are significantly (p&lt;0.05) decrease in subclinical mastitis affected animals when compared to healthy cows. Haemato-biochemical parameters can be used as important for pathological state of subclinical mastitis animals.

Meta analysis of the prevalence of subclinical mastitis in dairy cattle

Mastitis, which is defined as the inflammation of mammary tissue caused by infectious agents such as bacteria, yeast, fungi and viruses, is considered to be one of the most important problems of dairy enterprises due to reduced milk yield and milk quality. Therefore, studies on mastitis have been continuous from past to present. The presence of too many studies conducted in all around the world in order to estimate the prevalence of mastitis and to determine the factors affecting the disease has necessitated systematic review or meta-analysis studies on this subject. In this study, it was aimed to perform the meta-analysis for the prevalence of cow and udder quarter-based subclinical mastitis in 193 studies conducted around the world, and to determine the effects of some factors on the prevalence of subclinical mastitis using subgroup and meta-regression methods. Because high heterogeneity was detected between studies in the analysis, the random effects model (Der Simonian-Laird method) (Q=15149.869, df=188, p&lt;0.001, I2=98.759; Q=72142.706; df=174, p&lt;0.001; I2=99.774) was used in this study. The publication biases in the study samples were determined by the use of Egger's linear regression test, the Begg and Mazumdar rank correlation test and funnel plots. As a result of the study, the common prevalence of subclinical mastitis in cow and udder quarter-based studies were calculated as 0.46 (95% CI: 0.43-0.48) and 0.32 (95% CI: 0.30-0.34) respectively. The meta-analysis conducted in this study has enabled the elimination of inconsistencies in the prevalence of subclinical mastitis in individual studies conducted around the world, and has provided a stronger and more precise estimate.

Prevalence of Subclinical Mastitis in Holstein-Friesian Cow Dairy Among Small-Scale Farms in Batu, Indonesia

Prevalence of Subclinical Mastitis in Holstein-Friesian Cow Dairy Among Small-Scale Farms in Batu, Indonesia

Determination of Subclinical Mastitis Prevalence in Dairy Cows in Türkiye through Meta-Analysis and Production Loss Calculation

Determination of Subclinical Mastitis Prevalence in Dairy Cows in Türkiye through Meta-Analysis and Production Loss Calculation

Antibiotic Sensitivity of Pathogenic Bacteria Associated with Subclinical Mastitis of Dairy Cows in the Poro Region of the Ivory Cost

Subclinical mastitis is the most considered pathology in dairy farming and is responsible for economic losses in cows. The condition remains asymptomatic in dairy cows and treatment is mainly done without laboratory analysis. The objective of this work is to research bacterial causes of subclinical mastitis in dairy cows and to study their sensitivity to certain antibiotics. Thus, this study was carried out in four departments (Korhogo, Sinématiali, Dikodougou and M'bengué) in the Poro region (Ivory Coast) from May to August 2022 in traditional farms on 288 neighborhood milk samples taken from dairy cows with subclinical mastitis. The milk samples were analyzed using standard bacteriological isolation and identification techniques. Staphylococcus aureus were isolated on Baird-Parker potassium tellurite agar and mixed with egg yolk, Klebsiella spp isolated on MacConkey agar, Escherichia coli isolated on MacConkey, Pseudomonas aeruginosa isolated on TSA and King A agar, Micrococcus spp isolated on Chapman agar; then incubated at 37°C for 24 to 48 hours. The identification of bacteria was carried out by standard methods (appearance of colonies, Gram staining, catalase test, coagula-associated oxidase test, etc.). The biochemical characteristics were studied using the API Bio Mérieux galleries (API Staph and API20E etc.) The sensitivity of the main germs isolated was tested against ten (10) antimicrobials including those used in the treatment of mastitis by veterinary clinicians in the region. from Poro.The bacteriological analysis were identified 43% of Gram-positive cocci in minority, with particulary 18% of Staphylococcus aureus. In majority, Gram-negative bacilli were detected at 57% with particulary 38% of Enterobacteria (Klebsiella spp and Escherichia coli). The antibiogram showed excellent sensitivity to Staphylococcus aureus to Gentamycin 100%, good sensitivity to chloramphenicol and neomycin at 90% then acceptable sensitivity to the Trimethoprim-Sulfamethoxazole combination, to cefalexin of 80%. The coagulase negative staphylococcus (SCN) group revealed good sensitivity to Cefalexin and Gentamicin of (87.5%) and acceptable sensitivity to Chloramphenicol, Neomycin of (75%) each. On the other hand, Enterobacteria showed excellent resistance to Ampicillin, Spiramycin and Penicillin 100% and acceptable resistance to Gentamycin (95.84%). Remarkable resistance has been observed on the following antibiotics : Ampicillin, Penicillin and Colistin. This remarkable resistance was noted in Staphylococci (100% for Staphylococcus aureus and 87.5% for SCN) and Enterobacteria. Given these results, suggestions were made for the treatment and prevention of subclinical mastitis on farms in the Poro region (northern Ivory Coast).

Environmental and Breed Risk Factors Associated with the Prevalence of Subclinical Mastitis in Dual-Purpose Livestock Systems in the Arauca Floodplain Savannah, Colombian Orinoquia.

The aim of this study was to assess the environmental and breed risk factors associated with the prevalence of subclinical mastitis (SCM) in cows in the dual-purpose livestock system of Arauca, Colombian Orinoquia. Milk samples were taken from 1924 mammary quarters, corresponding to 481 cows on 28 different farms, and the California Mastitis Test (CMT) was applied. Risk factors associated with SCM were determined using multiple logistic regression analysis. The response variable was the presence (1) or absence (0) of SCM. Breed was included as a genetic risk factor, and daily milk production, number of cows in production, lactation month, calving number, cow age, climatic period, and body condition were included as environmental risk factors. The analysis of the odds ratio (OR) of significant effects indicated that the factors significantly associated with the presence of SCM were the number of cows (OR = 2.29; p = 0.005), milk production (OR = 0.88; p = 0.045), and the Taurus-Indicus breeds (OR = 1.79; p = 0.009) and composite breed (OR = 3.95; p = 0.005). In this study, the occurrence of SCM was determined by the following risk factors: number of cows, milk production, and breed. Likewise, the highest prevalence seemed to occur on farms with less technological development and sanitary management of producers from the lowest socioeconomic stratum.

Status of subclinical mastitis in lactating cows of selected dairy farms in Bangladesh and farmers’ understanding of mastitis

Background: Subclinical mastitis, a disease that is economically important to dairy cows, affects milk production. Management of udder health is an essential element in the process of safe milk production. Consumption of milk with a high somatic cell count (SCC) may also pose a health risk to humans. Objectives. We aimed to evaluate the SCC method for the detection of SCM in dairy cows and to assess farmers’ knowledge, attitudes, and practices towards mastitis detection and control. Methods. A cross-sectional study was conducted to evaluate the current status of subclinical mastitis (SCM) in lactating dairy cows. The research work was also designed to assess farmers’ knowledge, attitudes, and practices about bovine mastitis. A total of 320 milk samples from 80 lactating cows were collected for physical examination and tested for subclinical mastitis using SCC. Results. Out of 80 lactating cows examined, 53 (66%, 95% CI: 55-76%) cows were diagnosed with subclinical mastitis. The average cow level SCC per ml of milk was 503101. According to the farmers’ self-report, 100% of farms practiced hand milking and 100% of milkmen washed their hands before milking. The majority of farms (90%) had brick floors. Most of the farmers (70%) knew about screening for subclinical mastitis. However, they never performed screening to detect subclinical mastitis. Conclusion. The high prevalence of SCM in dairy raised significant concerns about farm management, personal hygiene and biosecurity practices. Further study is needed to identify the etiologies of SCM and its associated risk factors.

Epidemiological Studies of Subclinical Mastitis in Dairy Goats in Lumajang Regency, East Java, Indonesia

Subclinical mastitis is an economically important disease in dairy goat farming. Lumajang is a center for dairy goats in East Java. However, routine examination of subclinical mastitis for screening tests has no data. This study aimed to provide prevalence data and identification factors that influenced subclinical mastitis. Therefore, this study was carried out as part of the national surveillance program. The research design is a cross-sectional study with simple random sampling. Samples came from 19 farms with a total individual sample of 224 dairy goats. Detection of subclinical mastitis using an undirect test with the California Mastitis Test (CMT). Identification of management factors and characteristics that can influence subclinical mastitis in dairy goat farms using a structured questionnaire. The results showed that the prevalence of subclinical mastitis in Lumajang District was 36.2%. There was a significant difference in subclinical mastitis in each village (p&lt;0.05). The highest prevalence of subclinical mastitis was in Kandangtepus village. A farmer's characteristic factor that significantly influences subclinical mastitis is the farmer's experience. The aspect of livestock management that significantly affects subclinical mastitis is structured work management. Subclinical mastitis was prevalent in dairy goats in Lumajang District and requires prevention efforts. Prevention approach through education for farmers to increase knowledge, attitude, and socialization to improve livestock management.

Factors Influencing Milk Quality and Subclinical Mastitis in Dairy Herds Housed in Compost-Bedded Pack Barn System

The compost-bedded pack barn (CBPB) system has been increasingly adopted by dairy farms due to its ability to enhance animal comfort and milk production. This study evaluated the associations among bedding characteristics, milk quality and composition, and subclinical mastitis (SCM) occurrence in dairy herds housed in CBPB systems. Over a period of six months, data related to milk quality and udder health and bedding sampling were collected from eight dairy farms. Monthly measurements of the bedding temperature and wind speed inside the CBPB were taken, while temperature and relative humidity data inside the CBPB were recorded using a datalogger. Bedding samples were subjected to analysis of moisture, pH, microbiological count, and carbon/nitrogen ratio. Data on milk composition (fat, protein, milk urea nitrogen, and total solids) and quality (somatic cell count and standard plate count) of bulk tank milk were obtained from DHIA results. Canonical correlation analyses were used to evaluate the association between the analyzed group variables, and linear regression models were used to identify associations between bedding characteristics and SCM occurrence in the studied herds. The bedding characteristics that most influenced milk composition and quality were moisture, temperature at 30 cm depth (T30), and bedding pH. Environmental variables played an important role in bedding composting, as they were closely related to the surface temperature and pH. Overall, 62.71% of the variation in milk quality and composition could be explained by the bedding variables, and 77.50% of the variation in the bedding variables was associated with environmental variables. Median SCM prevalence and incidence were 28.6 and 13.8%, respectively. An increase of 1 °C for T30 resulted in a 0.6% reduction in the prevalence of SCM. Additionally, the bedding surface temperature at 22.3 °C resulted in the highest incidence of SCM (~18.1%). Our results demonstrate the importance of controlling microclimatic conditions in the CBPB to optimize the bedding composting process and milk quality.

An Assessment of The Risk Factors Associated with Subclinical Mastitis in Small Holder Dairy Cows and Large Mechanized Dairy Cows in Parts of Kaduna State, Nigeria

It appears that small holder dairy farmers as well as large mechanized dairy farmers in Kaduna State do not seem to be aware of the subclinical mastitis situation in their cows. A cross-sectional study was carried out with the objective of establishing the prevalence of subclinical mastitis and related risk indicators and to assess their contribution to the occurrence of subclinical mastitis. Three field procedures based on the principles of herd health and production management were followed: clinical inspection, farm management inspection and farm records inspection. The California mastitis test (CMT) was carried out on quarter milk samples to determine the prevalence of subclinical mastitis. A total of 150 lactating cows from 30 herds were investigated. Clinical mastitis was detected in about 5.0% of the lactating cows, subclinical mastitis was found in 24.5% (about 25%) of the cows screened. Farm inspection revealed that, water scarcity, poor housing, hand milking, single udder towel and dairy labourers as most substantial (P &lt; 0.05) risk indicators. Overall, there was the epidemiological need to address such risk indicators.

Correspondence of Somatic Cell Counts in Bulk-Tank Milk to Prevalence of Subclinical Mastitis in Sheep Flocks.

The objective of the present study was to propose thresholds of somatic cell counts in bulk-tank milk indicative of the prevalence of subclinical mastitis in a flock. A retrospective analysis was performed on data from a longitudinal survey of subclinical mastitis in Greece, in which the prevalence of subclinical mastitis in 12 flocks sampled four times throughout a milking period was evaluated by collecting milk samples from individual ewes for bacteriological and cytological testing; further, cell counts in the bulk-tanks of the farms were also measured during the visits. Four cohorts were created: A, with cell counts in the bulk-tank milk between 0.100 × 106 and 0.400 × 106 cells mL-1, B, with cell counts between 0.400 × 106 and 650 × 106 cells mL-1, C, with cell counts between 0.650 × 106 and 900 × 106 cells mL-1, and D, with SCC between 0.900 × 106 and 1.450 × 106 cells mL-1. There was a significant positive correlation between prevalence of the infection in the flocks and somatic cell counts in bulk-tank milk on the same sampling occasion (p < 0.0001). There was also evidence of significant differences between the four cohorts in the mean prevalence rate of the infection (p < 0.0001). Ninety-five percent confidence intervals of the prevalence of subclinical mastitis according to the somatic cell counts in the bulk-tank milk were calculated as follows: for cohort A, 8.7% to 12.1%, for B, 12.4% to 19.4%, for C, 22.5% to 30.8% and for D, 27.3% to 45.3%. The information that may be thus obtained can be useful in guiding the implementation of various health management procedures for mastitis control in sheep flocks, with no need to perform milk sample collection from ewes and subsequent laboratory examinations.

Molecular characteristics of Staphylococcus aureus strains isolated from subclinical mastitis of water buffaloes in Guangdong Province, China.

Intramammary infections (IMI) in animals reared for milk production can result in large economic losses and distress to the animals. Staphylococcus aureus is an important causative agent of IMI in dairy cows, but its prevalence in water buffaloes has not been determined. Therefore, the current study was conducted to investigate the prevalence of subclinical mastitis in water buffaloes and the antimicrobial susceptibility, virulence genes and biofilm formation abilities of Staphylococcus aureus isolates recovered from water buffaloes in Guangdong, China. Staphylococcus aureus strains were isolated from milk samples of water buffaloes with subclinical mastitis, and twofold microdilution, PCR and crystal violet staining methods were used to determine antimicrobial susceptibility, distributions of virulence and antimicrobial resistance genes and biofilm formation ability, respectively. Our results indicated that 29.44% of water buffaloes were diagnosed with subclinical mastitis, and the most prevalent pathogens were Escherichia coli (96.17%), coagulase-negative staphylococci (CoNS) (67.60%) and S. aureus (28.57%). Most S. aureus isolates showed resistance to bacitracin, doxycycline, penicillin, florfenicol, and tetracycline but were susceptible to ciprofloxacin, ceftizoxime, cefoquinoxime, and ofloxacin. Moreover, 63.72% of S. aureus isolates were positive for tetM, and the prevalence of msrB, blaZ, mecA, fexA, and tetK ranged from 21.24 to 6.19%. All S. aureus isolates harbored clfB and icaA genes, and the virulence genes hla (93.8%), hld (91.15%), clfA (90.27%), fnbA (86.73%), and hlb (83.19%), and tsst, icaD, sec, see, fnbB, and sea showed a varied prevalence ranging from 3.5 to 65.49%. All S. aureus isolates possessed the ability to form biofilms, and 30.09% of isolates showed strong biofilm formation abilities, while 19.47% of isolates were weak biofilm producers. Our results indicated that subclinical mastitis is prevalent in water buffaloes in Guangdong, China, and S. aureus is prevalent in samples from water buffaloes with subclinical mastitis. Most S. aureus isolates were susceptible to cephalosporins and fluoroquinolones; thus, ceftizoxime and cefoquinoxime can be used to treat subclinical mastitis in water buffaloes.

Prevalence of antibiotic residues in milk samples of small-scale dairy households in Bengaluru, India

This study aimed to estimate the burden of subclinical mastitis in community setting, animal handlers’ knowledge, attitude and practices on mastitis and antibiotic use, and to detect antibiotic residues in milk samples. A total of 211 households belonging to four clusters of Karnataka state in Southern province of India were selected through 30-cluster approach. A total of 380 milk samples were analyzed for Subclinical Mastitis (SCM) by California Mastitis Test (CMT) and antibiotic residues by spore-based and Charm Rosa tests. Animal handler’s basic knowledge, attitude and practices (KAP) on antibiotics use were recorded. SCM prevalence was found 42% in the study site; antibiotic residues were detected in 21% (79/380) of milk samples; 7.1% and 5.52% of samples had maximum residual limits (MRL) and Multi Drug Residues (MDR), respectively. Antibiotic residues were detected in 32.22% of the households. Majority of animal handlers heard about antibiotics (83.31%), 51% of handlers treated the animals on their own and 23% of them bought antibiotics without prescription. High prevalence of SCM in the study setting and antibiotic load in milk samples raise food safety concern. Regulatory measures for prudent antibiotic use and knowledge dissemination among animal handlers for clean milk production are the measures required to tackle the problem.

Longitudinal Study of Subclinical Mastitis in Sheep in Greece: An Investigation into Incidence Risk, Associations with Milk Quality and Risk Factors of the Infection.

The objectives of this work were (a) to describe the incidence risk of subclinical mastitis in dairy flocks throughout the milking period, (b) to present potential associations of subclinical mastitis with the quality of milk and (c) to identify risk factors for high-incidence risk of the infection. A longitudinal study was performed in 12 dairy sheep flocks in Greece. Mammary secretion samples from 240 ewes and bulk-tank milk samples were collected in four repeated visits over a period of six months for bacteriological, chemical and cytological examinations. Overall, the incidence risk of subclinical mastitis throughout the study period was 51.7%, and it varied among farms from 25.0% to 75.0%. The respective figure for staphylococcal subclinical mastitis was 48.8%. The incidence risk of recurrence of subclinical mastitis among ewes in the flocks was 35.4%. The most frequently identified bacteria from cases of subclinical mastitis were S. aureus and S. simulans; of the mastitis-causing staphylococcal isolates, 65.4% were biofilm-forming. Somatic cell counts in bulk-tank milk progressively increased as the lactation period advanced, with significant increases seen on the third and fourth visits to the farms. Somatic cell counts in bulk-tank milk correlated well with prevalence of subclinical mastitis in flocks. A significant inverse correlation and a significant positive correlation were seen for prevalence of subclinical mastitis versus total protein content or added water in bulk-tank milk. During multivariable analysis, younger age of newborns when taken away from the dam and consequently delayed start of milking of ewes, omission of anti-mastitis vaccination of ewes and lack of employed staff on the farms emerged to be significantly associated (positively) with increased incidence risk of subclinical mastitis.

Prevalence and Risk Factors of Bovine Mastitis on Conventional Dairy Farms in Northwestern Algeria

Background: Algeria’s dairy sector is experiencing various obstacles, such as a high frequency of diseases in dairy farms, particularly mastitis. Nonetheless, there has been a scarcity of research on mastitis occurrence, notably in Algeria’s Western area. As a result, the purpose of this study was to investigate the prevalence of mastitis and its associated risk factors in Algeria’s northwest area. Methods: The study included 130 dairy cows from 17 farms. The California mastitis test (CMT) and visual inspection were used to determine the prevalence of subclinical and clinical mastitis. Result: The total cow-level prevalence was 68.50% (89/130), with clinical cases accounting for 3.10% (4/130) and subclinical cases accounting for 65.40% (85/130). The quarter-level prevalence of mastitis was 35.19% (183/520), with 3.08% (16/520) clinical cases and 32.11% (167/520) subclinical cases. The study found that parity, lactation stage and age were all significant intrinsic risk factors for mastitis (P less than 0.05). Additionally, cow cleanliness level, cleaning solution, wiping udder after washing and dry cow treatment were significant extrinsic risk factors linked with mastitis (P less than 0.05). Given the high prevalence of mastitis in this region, regular screening and treatment are crucial to minimize the risk of mastitis and enhance cow health.