Using milk leukocyte differentials for diagnosis of subclinical bovine mastitis

2017 ◽  
Vol 84 (3) ◽  
pp. 309-317 ◽  
Author(s):  
Juliano Leonel Gonçalves ◽  
Roberta L. Lyman ◽  
Mitchell Hockett ◽  
Rudy Rodriguez ◽  
Marcos Veiga dos Santos ◽  
...  
Keyword(s):  
Bovine Mastitis ◽  
Dairy Herd ◽  
Inflammatory Cells ◽  
Subclinical Mastitis ◽  
Absolute Number ◽  
Dairy Herds ◽  
Milk Samples ◽  
Lactating Cows ◽  
Automated Instrument ◽  
Culture Positive

This research study aimed to evaluate the use of the milk leukocyte differential (MLD) to: (a) identify quarter milks that are culture-positive; and (b) characterize the milk leukocyte responses to specific groups of pathogens causing subclinical mastitis. The MLD measures the absolute number and relative percentage of inflammatory cells in milk samples. Using the MLD in two dairy herds (170 and 172 lactating cows, respectively), we studied all lactating cows with a most recent monthly Dairy Herd Improvement Association somatic cell count (SCC) >200 × 103 cells/ml. Quarter milk samples from 78 cows meeting study criteria were analysed by MLD and aseptically collected milk samples were subjected to microbiological culture (MC). Based upon automated instrument evaluation of the number and percentage of inflammatory cells in milk, samples were designated as either MLD-positive or – negative for subclinicial mastitis. Positive MC were obtained from 102/156 (65·4%) of MLD-positive milk samples, and 28/135 (20·7%) of MLD-negative milk samples were MC-positive. When MC was considered the gold standard for mastitis diagnosis, the calculated diagnostic Se of the MLD was 65·4% (IC95% = 57·4 to 72·8%) and the Sp was 79·3% (IC95% = 71·4 to 85·7%). Quarter milks positive on MC had higher absolute numbers of neutrophils, lymphocytes and macrophages, with higher neutrophils% and lymphocytes% but lower macrophages%. The Log10 (N/L) ratios were the most useful ratio to differentiate specific subclinical mastitis quarters from healthy quarters. Use of the MLD on cows with monthly composite SCC > 200 × 103 cells/ml for screening at quarter level identified quarters more likely to be culture-positive.In conclusion, the MLD can provide an analysis of mammary quarter status more detailed than provided by SCC alone; however, the MLD response to subclinical mastitis was not found useful to specifically identify the causative pathogen.

Prevalence and distribution of mastitis pathogens in subclinically infected dairy cows in Flanders, Belgium

2007 ◽  
Vol 74 (4) ◽  
pp. 478-483 ◽  
Author(s):  
Sofie Piepers ◽  
Luc De Meulemeester ◽  
Aart de Kruif ◽  
Geert Opsomer ◽  
Herman W Barkema ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Geometric Mean ◽  
Dairy Herd ◽  
Subclinical Mastitis ◽  
Cross Sectional ◽  
Intramammary Infections ◽  
Milk Samples ◽  
Lactating Cows ◽  
Culture Positive ◽  
Mastitis Pathogens

The main objective was to determine the prevalence of intramammary infections (IMI) in dairy cows in Flanders, Belgium. Data were obtained from quarter milk samples of dairy herds subjected to a mandatory yearly screening of all lactating cows. A total of 178 668 quarter milk samples were collected at 1087 cross-sectional dairy herd screenings performed in three consecutive years. Of the dairy cows, 40% had at least one culture-positive quarter. More than 50% of all IMI were caused by non-aureus staphylococci. Streptococcus agalactiae is almost eradicated in Flanders, whereas Staphylococcus aureus was isolated from 18% of the culture-positive quarters. In addition, the distribution of mastitis pathogens in quarter milk samples from selected dairy cows with an elevated somatic cell count (SCC) is described. From 6390 cows with a geometric mean composite SCC ⩾250 000 cells/ml, nearly 65% had at least one culture-positive quarter. The majority of the IMI were caused by non-aureus staphylococci (41·1%), whereas Staph. aureus and aesculin-positive cocci were found in respectively 25% and 18% of the culture-positive milk samples. We conclude that more efforts are needed in the prevention and control of subclinical mastitis in Flanders. Non-aureus staphylococci are the predominant cause of IMI, warranting more research regarding the epidemiology and pathogenicity of those species.

scholarly journals Molecular Detection and Sensitivity to Antibiotics and Bacteriocins of Pathogens Isolated from Bovine Mastitis in Family Dairy Herds of Central Mexico

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Ma. Fabiola León-Galván ◽  
José E. Barboza-Corona ◽  
A. Arianna Lechuga-Arana ◽  
Mauricio Valencia-Posadas ◽  
Daniel D. Aguayo ◽  
...  
Keyword(s):  
Bacillus Thuringiensis ◽  
Bovine Mastitis ◽  
Dairy Herd ◽  
Subclinical Mastitis ◽  
Herd Size ◽  
Clinical Mastitis ◽  
Dairy Herds ◽  
Coagulase Negative Staphylococci ◽  
California Mastitis Test ◽  
Streptococcus Uberis

Thirty-two farms (n=535cows) located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM) and clinical mastitis (CLM) were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins ofBacillus thuringiensiswas tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT) (≥3) and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY), lactation number (LN), herd size (HS), and number of days in milk (DM) were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH), LN, HS, and DMP<0.01, and correlations between udder quarters from the CMT were around 0.49P<0.01. Coagulase-negative staphylococci were mainly identified, as well asStaphylococcus aureus,Streptococcus uberis,Brevibacterium stationis,B. conglomeratum, andStaphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized byBacillus thuringiensisinhibited the growth of multiantibiotic resistance bacteria such asS. agnetis,S. equorum,Streptococcus uberis,Brevibacterium stationis, andBrachybacterium conglomeratum, but they were not active againstS. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study.

scholarly journals Etiological agents of bovine mastitis in Poland

2020 ◽  
Vol 76 (01) ◽  
pp. 6339-2020
Author(s):  
HENRYK KRUKOWSKI ◽  
HENRYKA LASSA ◽  
EWA ZASTEMPOWSKA ◽  
SEBASTIAN SMULSKI ◽  
HANNA BIS-WENCEL
Keyword(s):  
Bovine Mastitis ◽  
Subclinical Mastitis ◽  
Dairy Herds ◽  
Gram Positive ◽  
Milk Samples ◽  
Appropriate Treatment ◽  
Microbiological Methods ◽  
Regional Location ◽  
Etiological Agents ◽  
Mastitis Pathogens

This research paper addresses the hypothesis that the incidence of various bovine mastitis pathogens is subject to change over time and across regions. The aim of the research was to determine the pathogen species that are currently the etiological agents of mastitis in Polish dairy herds. This comprehensive study was conducted in the period 2009-2017 and included all the Polish provinces, distinguishing between those with high and low numbers of dairy cattle. Over eight years 38,852 quarter milk samples were obtained from 22,587 cows with clinical and subclinical mastitis from herds located in all 16 provinces in Poland. Milk samples were cultured using standard microbiological methods. Most of them were positive for microorganisms but there was also part of bacteriologically negative and contaminated samples. Gram-positive catalase-negative cocci and staphylococci were the most prevalent pathogens. The growth of other microorganisms such as Gram-negative and Gram-positive bacilli, yeasts and algae was observed at lower frequencies. There were differences in the prevalence of microorganisms depending on the region. In the eastern part of the country a higher number of Streptococcus agalactiae infections than in other regions was observed. This paper provides the latest data on microbial species, frequency of their occurrence and regional location within Poland. The knowledge of mastitis pathogens enables appropriate treatment and to make prevention recommendations for the herds.

scholarly journals Subclinical intramammary infection does not affect bovine milk ethanol stability

2018 ◽  
Vol 55 (2) ◽  
pp. e135173
Author(s):  
Cristian Marlon de Magalhães Rodrigues Martins ◽  
Juliano Leonel Gonçalves ◽  
Bruna Gomes Alves ◽  
Marcos André Arcari ◽  
Marcos Veiga dos Santos
Keyword(s):  
Bovine Milk ◽  
Subclinical Mastitis ◽  
Milk Composition ◽  
Dairy Herds ◽  
Intramammary Infection ◽  
Milk Samples ◽  
Lactating Cows ◽  
Natural Exposure ◽  
Major Pathogens ◽  
Ethanol Stability

The present study hypothesized that intramammary infection (IMI) might reduce milk ethanol stability (MES), mainly when IMI is caused by major pathogens. Thus, this study evaluated the effect of IMI on bovine MES using a natural exposure experimental design. Ninety-four lactating cows from five dairy herds were selected once they were determined to have an IMI, based on milk bacteriological culturing with positive isolation and somatic cell count (SCC) > 200×103 cells/mL in two out of three composite milk samples collected during three consecutive weeks. After selection, cows were sampled a second time (within two weeks) for evaluation at mammary quarter level (n = 326): milk yield (kg/quarter/day), MES, composition (fat, protein, lactose, casein, total solids and solids-non-fat), and bacteriologic culture. The effect of subclinical mastitis on MES was tested by two models: 1) comparison of healthy vs. infected quarters; and 2) comparison of contralateral mammary quarter within cow. The only milk composition variable associated with MES was lactose (r = 0.18; P < 0.01). Subclinical IMI did not affect MES when the comparison was performed using both models (1 and 2). Likewise, MES did not change when infected quarters were sorted into two groups of pathogens (major, minor and infrequent; and contagious, environmental, minor and infrequent) and compared with healthy mammary quarters. Considering the results of both models, subclinical IMI did not affect MES of dairy cows.

scholarly journals Prevalence of methicillin-resistant Staphylococcus aureus and pattern of antimicrobial resistance in mastitis milk of cattle in Chitwan, Nepal

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Asmita Shrestha ◽  
Rebanta Kumar Bhattarai ◽  
Himal Luitel ◽  
Surendra Karki ◽  
Hom Bahadur Basnet
Keyword(s):  
Public Health ◽  
Staphylococcus Aureus ◽  
Antimicrobial Resistance ◽  
Subclinical Mastitis ◽  
World Health ◽  
Dairy Herds ◽  
Microbiological Analysis ◽  
Biochemical Tests ◽  
Methicillin Resistant ◽  
Milk Samples

Abstract Background The threat of methicillin-resistant Staphylococcus aureus (MRSA) exists globally and has been listed as a priority pathogen by the World Health Organization. One of the sources of MRSA emergence is livestock and its products, often raised in poor husbandry conditions. There are limited studies in Nepal to understand the prevalence of MRSA in dairy animals and its antimicrobial resistance (AMR) profile. A cross-sectional study was conducted in Chitwan, one of the major milk-producing districts of Nepal, from February 2018 to September 2019 to estimate the prevalence of MRSA in milk samples and its AMR profile. The collected milk samples (n = 460) were screened using the California Mastitis Test (CMT) and positive samples were subjected to microbiological analysis to isolate and identify S. aureus. Polymerase Chain Reaction (PCR) was used to identify the presence of the mecA gene and screen for MRSA. Results In total, 41.5% (191/460) of milk samples were positive in the CMT test. Out of 191 CMT positive milk samples, the biochemical tests showed that the prevalence of S. aureus was 15.2% (29/191). Among the 29 S. aureus isolates, 6.9% (2/29) were identified as MRSA based on the detection of a mecA gene. This indicates that that 1.05% (2/191) of mastitis milk samples had MRSA. The antibiotic sensitivity test showed that 75.9% (22/29) and 48.3% (14/29) S. aureus isolates were found to be sensitive to Cefazolin and Tetracycline respectively (48.3%), whereas 100% of the isolates were resistant to Ampicillin. In total 96.6% (28/29) of S. aureus isolates were multidrug-resistant (MDR). Conclusions This study revealed a high prevalence of S. aureus-mediated subclinical mastitis in dairy herds in Chitwan, Nepal, with a small proportion of it being MRSA carrying a mecA gene. This S. aureus, CoNS, and MRSA contaminated milk poses a public health risk due to the presence of a phenotype that is resistant to very commonly used antibiotics. It is suggested that dairy herds be screened for subclinical mastitis and treatments for the animals be based on antibiotic susceptibility tests to reduce the prevalence of AMR. Furthermore, future studies should focus on the Staphylococcus spp. to explore the antibiotic resistance genes in addition to the mecA gene to ensure public health.

scholarly journals Mycoplasmal mastitis in dairy cows in the Moghan region of Ardabil State, Iran : short communication

2006 ◽  
Vol 77 (4) ◽  
Author(s):  
C. Ghazaei
Keyword(s):  
Dairy Cows ◽  
Short Communication ◽  
Bovine Mastitis ◽  
Subclinical Mastitis ◽  
Clinical Mastitis ◽  
Mycoplasma Bovis ◽  
Bulk Tank Milk ◽  
Milk Samples ◽  
The World ◽  
Bulk Tank

Mycoplasmas are an important and economically significant cause of mastitis in dairy cows in various parts of the world. The organisms are highly contagious, with the main reservoir of infection originating from cows with subclinical mastitis. In 1998 the 1st cases of bovine mastitis due to Mycoplasma bovis were diagnosed in Ardabil State, Iran. An investigation was carried out with the aim of establishing the extent of mycoplasma infections in dairy cows in Ardabil State. Milk samples obtained from 80 cows with clinical mastitis were cultured in the laboratory for the presence of mycoplasmas. Similarly, 48 bulk-tank milk samples were examined for the presence of mycoplasmas. A modified Hayflick broth was used to isolate the mycoplasmas and an immunoperoxidase test used for the species identification of the isolates. Mycoplasma bovis was isolated from 39 (48.75 %) of the clinical mastitis samples and from 48 of the bulk-tank milk samples tested. This indicated that mycoplasma udder infections were more prevalent in dairy cows in Ardabil State than previously thought.

scholarly journals Effect of including herbal choline in the diet of a dairy herd; a multiyear evaluation

2019 ◽  
pp. 477 ◽  
Author(s):  
Alfredo Gutiérrez R., Alfredo Gutiérrez ◽  
Carlos Sánchez ◽  
Germán D. Mendoza
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Dairy Herd ◽  
Health Indicators ◽  
Subclinical Mastitis ◽  
Feed Additives ◽  
Lactating Cows ◽  
Chi Squared ◽  
Important Health ◽  
Using Data

A linear mixed model and chi-squared tests were used to estimate the effects of the dietary inclusion of herbal choline at 0.071 % of the diet in the entire dairy herd (target dose of 17 g/d in lactating cows) using data from six years in a commercial farm. The feed plant additive (BioCholine) was included in the premix spanning three years (2016-2018) feeding 442 cows average per year and information was compared with the three previous years (2013 – 2015; 424 cows average per year). Energy corrected milk in the period 2016-2018 was increased by 1.57% (p<0.001) compared to years 2013-2016 (36.36 vs. 35.80 kg/d). Fertility in cows during first lactation was improved (P<0.01) with the feed plant additive (45.33 vs. 37.0%). The period feeding herbal choline (2016-2018) showed a reduction (p<0.0001) in abortions (15.65 to 7.29%) and clinical (p<0.005; 12.59 to 6.95%) and subclinical mastitis (p<0.05; 8.65 to 5.22%) and in respiratory disorders (p<0.10; 12.42 to 8.56%) whereas hypocalcaemia incidence was increased (p<0.01) from 1.73 to 6.22%. Total herd replacement was reduced during the years 2016-2018 by 5.73% (p<0.05) without effects in mortality. Inclusion of the plant feed additives containing conjugates of choline improved milk yield, fertility in first lactation cows and important health indicators which help to reduced herd replacement.

scholarly journals Risk factors associated with the occurrence of multiresistant Staphylococcus spp. isolated from bovine subclinical mastitis in northern Brazil

2022 ◽  
Vol 43 (2) ◽  
pp. 901-910
Author(s):  
Lilian Bernardina Ferreira ◽  
◽  
Larissa de Freitas Santiago Israel ◽  
Renata Fernandes Rabello ◽  
Guilherme Nunes de Souza ◽  
...  
Keyword(s):  
Risk Factors ◽  
Multidrug Resistance ◽  
Phenotypic Expression ◽  
Bovine Mastitis ◽  
Subclinical Mastitis ◽  
Isolation And Identification ◽  
Phenotypic Profile ◽  
Milk Samples ◽  
California Mastitis Test ◽  
Staphylococcus Spp

Staphylococcus bacteria are often associated with subclinical bovine mastitis. This study aimed to identify multiresistant Staphylococcus spp. associated with subclinical mastitis and the associated risk factors. Twenty-three dairy farms with a history of decrease in milk production, located in the lower Acre region, Brazil, were selected. An epidemiological questionnaire was provided in all farms. All animals were examined using the California Mastitis Test (CMT) and their milk samples were collected for bacterial culture. After isolation and identification, the disk diffusion antimicrobial susceptibility test was performed against nine classes of antimicrobials. Of the 339 cows examined using the CMT, 108 had mastitis. A total of 229 milk samples were collected from individual teats. MALDI-TOF MS found isolates belonging to eight species of Staphylococcus, in 101 of these samples. S. chromogenes (58.4%) demonstrated strongest resistance to the nine classes of antimicrobial active principles. Nineteen isolates with multidrug resistance phenotypic profile were identified. This phenotypic expression indicates wide circulation of resistant genes in this species. The presence of multidrug resistance in Staphylococcus spp. in this study was correlated with lack of water for cleaning the corral, which is a preventive factor, minimizing the transmission and persistence of pathogens in the farms.

scholarly journals Identification of subclinical mastitis caused by Mycoplasma spp. from screenings of bulk tanks

2018 ◽  
Vol 70 (6) ◽  
pp. 1793-1797
Author(s):  
S.F. Joaquim ◽  
F.F. Guimarães ◽  
A. Salina ◽  
N.B. Junqueira ◽  
E.N. Gomes ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Subclinical Mastitis ◽  
Mammary Glands ◽  
Dairy Herds ◽  
Mycoplasma Bovis ◽  
Chain Reaction ◽  
Milk Samples ◽  
Polymerase Chain ◽  
Bulk Tank ◽  
Mycoplasma Spp

ABSTRACT Mastitis caused by Mycoplasma spp., regardless of species, are considered highly contagious pathogens and, usually was not responsive to antimicrobial therapy. Five dairy herds, comprising 489 animals and 1,956 mammary glands, were used in this study. Milk samples were obtained from bulk tanks and subjected to polymerase chain reaction (PCR) for the identification of Mollicutes, Mycoplasma spp., and Mycoplasma bovis. Moreover, individual samples from cases of clinical and subclinical mastitis in quarters of the dairy herds’ animals that yielded a positive PCR upon bulk tank analysis were subjected to molecular analysis. Only one bulk tank was positive for class Mollicutes by PCR. All positive samples classified as mastitis teats had their DNA extracted and tested by PCR for both class Mollicutes and M. bovis. Of these, two (2.08%) were positive for Mycoplasma genus, although none was positive for M. bovis. This result suggests that the PCR of bulk tanks is a viable tool in monitoring and preventing mastitis infections caused by Mycoplasma spp.

scholarly journals Prevalence, Etiology, and Risk Factors of Mastitis in Dairy Cattle in Embu and Kajiado Counties, Kenya

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Christine M. Mbindyo ◽  
George C. Gitao ◽  
Charles M. Mulei
Keyword(s):  
Management Practices ◽  
Health Hazard ◽  
Previous History ◽  
Bovine Mastitis ◽  
Subclinical Mastitis ◽  
Control Measures ◽  
Economic Losses ◽  
Isolation And Identification ◽  
Cross Sectional ◽  
Milk Samples

Bovine mastitis continues to be a leading cause of heavy economic losses in the dairy industry and a public health hazard globally. This cross-sectional study investigated the prevalence, etiologies of clinical and subclinical mastitis, and associated predisposing factors in Embu and Kajiado counties in Kenya. A semistructured questionnaire was administered to 154 smallholder dairy farmers to collect data on management practices, animal factors, and disease history. A total of 395 dairy cows were initially screened for subclinical mastitis using the California mastitis test (CMT), and milk samples were aseptically collected. Both CMT positive and CMT negative samples were analyzed using conventional bacteriological isolation and identification procedures. In the present study, the overall prevalence of mastitis based on CMT and clinical examination was 80% (316/395), out of which 6.8% (27/395) was clinical mastitis, while 73.1% (289/395) was subclinical mastitis. Based on culture, the overall prevalence of clinical and subclinical mastitis was 51.6% (815/1580), 74.4% (294/395), and 76.6% (118/154) at the quarter, cow, and farm level, respectively. From the 1574 milk samples analyzed by cultured, 1016 bacteria were yielded. The predominant bacteria were coagulase-negative Staphylococcus (CNS), 42.8% (435/1016), and in decreasing order, Streptococcus species, 22.2% (226/1016), Staphylococcus aureus, 15.7% (160/1016), and Pseudomonas aeruginosa, 5.1% (52/1016), and the least was Enterobacter species, 0.7% (7/1016), while 23.7% of the sample yielded no bacterial growth. Risk factor analysis revealed that milking mastitic cows last (p=0.002), using a clean udder drying towel for each cow (p=0.033) and previous history of mastitis (p=0.046) were significantly associated with presence of mastitis. The current study has shown a relatively high prevalence of subclinical mastitis with CNS as predominant bacteria. Therefore, control measures are urgently warranted. Management factors such as milking mastitic cows last, using a clean towel for udder drying for each cow, and culling mastitic cows should be considered and included in the Kenyan mastitis control programs.

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