Prevalence of E. coli in milk samples from cows with mastitis in the southwest of Puerto Rico.
Board Location: #33
Discipline: Biological Sciences
Subcategory: Microbiology/Immunology/Virology
Session: 1
Wilgeyshka S. Acevedo Acevedo - University of Puerto Rico Aguadilla
Co-Author(s): Yavier Nazario Cáceres University of Puerto Rico Aguadilla, PR Javier O. Galarza Aviles University of Puerto Rico Aguadilla, PR, Stephanie M González Aviles University of Puerto Rico Aguadilla, PR J
The specific aim of this study is to investigate the prevalence of E. coli in milk samples from dairy cows with mastitis in farms at the southwest of Puerto Rico using microbiology and molecular biology techniques. This research is crucial due to the fact that the transmission of pathogenic bacteria to the human food chain is detrimental to the health of every individual, and it can cause economic losses in the dairy industry. We expect to find a higher prevalence of E. coli in milk samples from cows with mastitis compared to healthy cows. Milks samples were collected from cows with mastitis and healthy cows and transported to the laboratory for further analysis. Samples are inoculated in selective media for gram-negative bacteria and incubated at 37C for 48 hours. Colony count and morphological analysis is then performed to select suspected E. coli colonies based on known characteristics. Bacterial colonies suspected of being E. coli where subjected to specific biochemical tests. Confirmation of E. coli identification will be obtained by genomic amplification of adk target gene by PCR and Real-time PCR analysis. Milk samples from healthy cows will be used as controls. In a preliminary pilot study, twenty-two milk samples were inoculated in Nutrient Agar. Selected colonies based on morphological analysis and gram staining were cultured in EMB/MacConkey. None of the samples grew in EMB or MacConkey agars. Although other bacteria were identified, E. coli was not detected in any of the 11 mastitis samples nor the 10 healthy samples. Preliminary data suggests that E. Coli is not a key pathogen in mastitis infection at this particular farm in Puerto Rico. Current studies are focused on collection of additional milk samples, expansion of biochemical tests performed to our samples, and PCR and qRT-PCR amplification of target genes for bacterial identification confirmation. Rana EA, Fazal MA, Alim MA. Frequently used therapeutic antimicrobials and their resistance patterns on Staphylococcus aureus and Escherichia coli in mastitis affected lactating cows. Int J Vet Sci Med. 2022 Feb 28;10(1):1-10. doi: 10.1080/23144599.2022.2038494. PMID: 35291582; PMCID: PMC8890510.Adzitey F, Yussif S, Ayamga R, Zuberu S, Addy F, Adu-Bonsu G, Huda N, Kobun R. Antimicrobial Susceptibility and Molecular Characterization of Escherichia coli Recovered from Milk and Related Samples. Microorganisms. 2022 Jul 1;10(7):1335. doi: 10.3390/microorganisms10071335. PMID: 35889054; PMCID: PMC9320388.
Funder Acknowledgement(s): This research project was supported by PR-LSAMP U ndergraduate Research Scholarships, and RUTAS Program USDA Grant Award #2018-38422-28570 and AREA R15 NIH Grant Award #1R15HD109919-01 granted to Juliana Perez Laspiur PhD. University of Puerto Rico at Aguadilla, Aguadilla, PR.
Faculty Advisor: Juliana Pérez Laspiur- PHD, Juliana.perez-laspiur@upr.edu
Role: I was involved in every step of this research. From buying the materials to accomplish this research, collecting the milk samples from the farm, inoculating the bacterias, performing biochemical test and making the statistical analysis.