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Sun M, Gao J, Ali T, Yu D, Zhang S, Khan SU, Fanning S, Han B. Characteristics of Aerococcus viridans isolated from bovine subclinical mastitis and its effect on milk SCC, yield, and composition. Trop Anim Health Prod 2017; 49:843-849. [PMID: 28321788 DOI: 10.1007/s11250-017-1271-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 03/14/2017] [Indexed: 10/19/2022]
Abstract
Aerococcus viridians (A. viridans), an environmental Gram-positive bacterium, has been documented to be associated with bovine mastitis. However, its exact role in bovine mastitis and the changes it brings about in milk characteristics are not yet known. The objectives of the current study were to describe the antibiotic resistance of A. viridans from bovine mastitis as well as the correlation between existence of this pathogen in udders and the somatic cell counts (SCC), daily milk yield, and composition of individual cow. One-year sampling for subclinical mastitis composite milk was conducted based on monthly DHI data from September 2013 to August 2014, in a commercial herd located in Beijing, China. All samples were cultured and pathogens were identified using microbiology method. A. viridians isolates were further identified by API identification system and 16S ribosomal RNA (rRNA) sequencing method. Kirby-Bauer disk diffusion method was used to test the antibiotic resistance of A. viridians against kinds of antimicrobial substance. SCC, milk yield, and milk composition data were from monthly Dairy Herd Improvement (DHI) results. Results showed that a total of 279 (16.67%) A. viridans isolates were identified from among 1674 bacterial isolates cultured from milk samples with high SCC. The incidence of mastitis caused by A. viridans was the highest (48-53%) during the summer season. Majority of the isolates were susceptible to most of antimicrobial compounds tested, especially to β-lactams, but were found to be resistant (50-90%) to aminoglycosides, sulfonamides, and tetracycline. The average SCC of the A. viridans infected cows was significantly higher (1000.0 × 103 cells/mL) (P < 0.01) as compared to healthy cows (72.4 × 103 cells/mL) and daily milk yield decreased (P > 0.05) by 1.86 kg/day. Reductions were also observed in fat content (P > 0.05), lactose (P < 0.01), and total solids (P > 0.05), whereas protein content increased significantly (P < 0.01) in milk samples of cows infected with A. viridans. The results of this study suggest that A. viridans could be considered as an emerging aetiological agent of bovine subclinical mastitis wherein it exerts an effect on SCC, milk yield, and composition.
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Affiliation(s)
- Meng Sun
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China
| | - Jian Gao
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China
| | - Tariq Ali
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China
| | - Dan Yu
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China
| | - Shiyao Zhang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China
| | - Saeed U Khan
- Department of Animal Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Séamus Fanning
- UCD-Centre for Food Safety, School of Public Health, Physiotherapy & Sports Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Bo Han
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
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Roque K, Lim GD, Jo JH, Shin KM, Song ES, Gautam R, Kim CY, Lee K, Shin S, Yoo HS, Heo Y, Kim HA. Epizootiological characteristics of viable bacteria and fungi in indoor air from porcine, chicken, or bovine husbandry confinement buildings. J Vet Sci 2016; 17:531-538. [PMID: 27456779 PMCID: PMC5204031 DOI: 10.4142/jvs.2016.17.4.531] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 04/13/2016] [Accepted: 06/08/2016] [Indexed: 11/20/2022] Open
Abstract
Microorganisms found in bioaerosols from animal confinement buildings not only foster the risk of spreading diseases among livestock buildings, but also pose health hazards to farm workers and nearby residents. This study identified the various microorganisms present in the air of swine, chicken, and cattle farms with different kinds of ventilation conditions in Korea. Microbial air samples were collected onto Petri dishes with bacterial or fungal growth media using a cascade impactor. Endotoxin levels in total dust were determined by the limulus amebocyte lysate kinetic QCL method. Prevalent Gram-positive bacteria were Staphylococcus (S.) lentus, S. chromogenes, Bacillus (B.) cereus, B. licheniformis, and Enterococcus faecalis, while the dominant fungi and Gram-negative bacteria were Candida albicans and Sphingomonas paucimobilis, respectively. Considering no significant relationship between the indoor dust endotoxin levels and the isolation of Gram-negative bacteria from the indoor air, monitoring the indoor airborne endotoxin level was found to be also critical for risk assessment on health for animals or workers. The present study confirms the importance of microbiological monitoring and control on animal husbandry indoor air to ensure animal and worker welfare.
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Affiliation(s)
- Katharine Roque
- Department of Occupational Health, College of Medical and Public Health Sciences, Catholic University of Daegu, Gyeongsan 38430, Korea
| | - Gyeong-Dong Lim
- Department of Occupational Health, College of Medical and Public Health Sciences, Catholic University of Daegu, Gyeongsan 38430, Korea
| | - Ji-Hoon Jo
- Department of Occupational Health, College of Medical and Public Health Sciences, Catholic University of Daegu, Gyeongsan 38430, Korea
| | - Kyung-Min Shin
- Department of Occupational Health, College of Medical and Public Health Sciences, Catholic University of Daegu, Gyeongsan 38430, Korea
| | - Eun-Seob Song
- Department of Occupational Health, College of Medical and Public Health Sciences, Catholic University of Daegu, Gyeongsan 38430, Korea
| | - Ravi Gautam
- Department of Occupational Health, College of Medical and Public Health Sciences, Catholic University of Daegu, Gyeongsan 38430, Korea
| | - Chang-Yul Kim
- Department of Occupational Health, College of Medical and Public Health Sciences, Catholic University of Daegu, Gyeongsan 38430, Korea
| | - Kyungsuk Lee
- National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Korea
| | - Seungwon Shin
- Department of Infectious Diseases and BK21 PLUS, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
| | - Han-Sang Yoo
- Department of Infectious Diseases and BK21 PLUS, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
| | - Yong Heo
- Department of Occupational Health, College of Medical and Public Health Sciences, Catholic University of Daegu, Gyeongsan 38430, Korea
| | - Hyoung-Ah Kim
- Department of Preventive Medicine, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
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Molecular and Phenotypic Characterization of Aerococcus viridans Associated with Subclinical Bovine Mastitis. PLoS One 2015; 10:e0125001. [PMID: 25919289 PMCID: PMC4412496 DOI: 10.1371/journal.pone.0125001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 03/19/2015] [Indexed: 11/21/2022] Open
Abstract
Aerococcus viridans is a wide spread bacterium in the environment and clinically this organism is associated with different diseases in animals and humans. However, the geno- and phenotypic characterization of A. viridans associated with bovine mastitis has not yet been reported. The objectives of this study were to investigate the genetic and phenotypic diversity of A. viridans isolates using three different molecular methods including 16S rRNA gene sequencing, pulsed-field gel electrophoresis and random amplified polymorphic DNA (RAPD) along with biochemical tests, including antimicrobial susceptibility test. In total, 60 A. viridans strains were cultured from dairy herds presenting with subclinical mastitis. The results of biochemical tests revealed that most of the isolates (75.0%) were accurately identified by API Rapid 20 Strep system and the majority of A. viridans strains (96.7%) were found to be catalase negative, while two (3.3%) isolates were weakly positive. All isolates were resistant to trimethoprim-sulfamethoxazole, followed by streptomycin (96.7%), tetracycline (65.0%) and clindamycin (56.7%) by minimum inhibition concentration-determining broth microdilution technique. As compared to the sequence of 16S rRNA gene, both PFGE and RAPD showed their capacities to discriminate the intra-species diversity of A. viridans. Furthermore, most of the isolates obtained from the same herd or region belonged to the same major RAPD group, which indicated that RAPD is an appropriate assay for tracking the origins of isolates and epidemiological studies of A. viridans. This is a novel approach to use three molecular techniques and to compare their efficiency regarding the genetic diversity of A. viridans. The data suggest that A. viridans associated with subclinical mastitis has a considerable phenotypic and genotypic diversity.
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