Brief Summary of Minutes of Annual Meeting

OBJECTIVE 1: Characterize host mechanisms associated with mastitis susceptibility, and resistance to improve economic outcomes and animal welfare.

University of Minnesota

Members: S. Godden, L. Caixeta, N. Noyes, B. Crooker, W. Knauer

UMN researchers submitted multiple manuscripts detailing associations between the host microbiome and mastitis outcomes. These companion studies showed associations between the teat epithelial microbiome and mastitis susceptibility, including associations between microbiome diversity and individual bacterial taxa and viruses within the teat apex microbiome.

The Ohio State University

Members: B. Enger

Contributors: K. Enger

A study was conducted to evaluate how the cow’s innate immune response damages mammary gland functionality and the secretory epithelium within the mammary gland. Cow mammary glands were infused with sterile irritants and then milked to assess changes in milk composition and measure the appearance of blood born factors in milk. Results were submitted for publication.

South Dakota State University

Members: T. Swartz

We received funding from USDA-NIFA-AFRI to explore the role of systemic inflammation during the peripartum period on mammary gland immune responses during an intramammary challenge in dairy cattle. We are currently conducting the studies outlined in this proposal and will begin reporting results in 2025.                

University of Vermont Agriculture Station

Members: Feng-Qi Zhao, John Barlow

Contributors: Chrissy Lalonde, Caitlin Jeffrey, Ashma Chakrawarti

Zhao lab at the University of Vermont investigated the impact of prostaglandin E2 (PGE2) on lipid synthesis in bovine mammary epithelial cells and determined the specific receptor(s) through which PGE2 exerts its effect. Cells treated with PGE2 produced 88 ± 3% the amount of triacylglycerols that untreated cells produced. However, in the presence of PGE2 receptors EP3 and EP4 inhibitors, triacylglycerol production was mostly restored to 96 ± 5% and 95 ± 6%, respectively, of original production. Cells grown with the broad-spectrum EP inhibitor had their triacylglycerol production restored to their original level (102 ± 5%). Our findings indicate that prostaglandin E2 reduces triacylglycerol production in bovine mammary epithelial cells, likely through at least two prostanoid receptors, EP3 and EP4.

OBJECTIVE 2:  Characterize agents associated with intramammary infections and assess their impact on milk quality and animal welfare

Cornell University

Members: Quinn Kolar, Matthias Wieland

Completed a study confirming the bacterial species associated with non-severe clinical mastitis in a randomized clinical trial based on results of on-farm culture.

Completed a study characterizing the antimicrobial susceptibility of non-aureus Staphylococci, Enterococci, Lactococci, and Streptococci isolated from milk samples of cows with clinical mastitis.

Hill Farm Research Station, LSU AgCenter

Member: William E. Owens

Advise dairy producers and fieldmen on mastitis prevention and control methods.

University of Minnesota

Members: S. Godden, L. Caixeta, N. Noyes, B. Crooker, W. Knauer

UMN researchers completed an analysis of non-aureus Staphylococcus spp. isolates obtained from the external teat epithelium of heifers with and without intramammary infections with Staphylococcus aureus. Phenotypic testing suggested that some strains of Staphylococcus were able to strongly inhibit growth of Staphylococcus aureus, while others were not. Whole-genome sequencing analysis of the same isolates revealed strong associations between gene profiles and the species of non-aureus Staphylococcus, but no strong associations between gene profiles and phenotypic inhibitory activity. Isolates obtained from a single cow during a single sampling event often exhibited substantial genomic diversity, suggesting that the external teat epithelium of individual cows can harbor a diversity of non-aureus Staphylococcus.

University of Missouri

Members: Pamela Adkins, John Middleton                                                                       

Contributors: Alyssa Novo

The University of Missouri research group has focused on assessing intramammary infection status among primigravid and nulligravid heifers.  We have worked in collaboration with the VT group on molecular characterization of Staphylococcus chromogenes, looking at isolates associated with teat ends, high somatic cell count, and low somatic cell count. We have also worked on evaluation of the in vitro ability of S. chromogenes isolates to inhibit the growth of S. aureus.

University of Vermont Agriculture Station

Members: Feng-Qi Zhao, John Barlow

Contributors: Chrissy Lalonde, Caitlin Jeffrey, Ashma Chakrawarti

The Barlow lab completed a field study of 19 Vermont dairy farms where we characterized 160 S. aureus isolates collected from cow quarter milk (CQM), bulk tank milk (BTM), human-hand and -nasal swabs. We found that the Staph aureus strain types colonizing humans working on dairy farms differed from those causing mastitis in dairy cows on the same farms. Humans were more likely to carry beta-lactam-resistant S. aureus compared to cows, and on organic farms only human-adapted blaZ positive STs were isolated from BTM. This work demonstrates that the presence of penicillin-resistant-human-adapted S. aureus on both organic and conventional dairy farms highlights a “One Health” concern at the junction of public and animal health. The Barlow lab also developed a whole genome sequencing pipeline combining Oxford nanopore long read sequencing and Illumina short read sequencing. This Hybrid Illumina-Nanopore genome sequencing and assembly improves identification of multilocus sequence types and antimicrobial resistance

genes of 62 Staphylococcus aureus isolates collected from Vermont dairy farms.

OBJECTIVE 3: Assess and apply new technologies and preventative strategies that advance mastitis control, milk quality and/or reduce antimicrobial usage

Cornell University

Members: Quinn Kolar, Matthias Wieland

Completed a retrospective cohort study investigating the association of individual quarter dry-off with udder health, milk production, and culling risk.

Completed a study confirming the bacterial species associated with non-severe clinical mastitis in a randomized clinical trial based on results of on-farm culture.

University of Minnesota

Members: S. Godden, L. Caixeta, N. Noyes, B. Crooker, W. Knauer

UMN researchers published work demonstrating that the majority of data generated from standard microbiome assays of bovine milk are likely to be contaminants, i.e., not native to the milk within the gland itself. These results have important implications for previous and future milk microbiome studies. The researchers made recommendations for dealing with this contamination problem in future studies.

Methods of processing recycled manure solids bedding on Midwest dairy farms II: Relationships between bedding characteristics and bedding bacterial count. F. Peña-Mosca,  S. Godden, E. Royster, B.A. Crooker, and J. Timmerman.  

The first objective of this study was to identify bedding characteristics associated with bedding bacterial count (BBC) in ready to use (RTU) recycled manure solids (RMS). The second objective was to explore the association between processing method and bedding characteristics in RTU solids. A third objective was to investigate factors associated with BBC in used solids (after placed in stalls). This observational study recruited 29 premises in Minnesota and Wisconsin. Farms were visited twice, once in August of 2019 and again in January of 2020. At each visit the herd manager/owner completed a questionnaire describing facilities, bedding and manure management, and mastitis control practices. Additionally, pre-processed RTU and used bedding samples were collected for determination of BBC (coliforms, Klebsiella spp., Streptococcus or Streptococcus-like organisms and Staphylococcus spp.) and bedding characteristics (dry matter (DM), organic matter (OM), water soluble carbohydrates, total nitrogen, soluble nitrogen and pH). Mixed linear regression showed that increased DM, decreased OM and RMS processing method were all associated with reduced BBC in RTU RMS samples. Processing method for RMS was associated with DM, total nitrogen and soluble nitrogen, but not other characteristics in RTU RMS samples. Low BBC in RTU solids, decreased OM in RTU solids, and use of deep bedding systems were associated with lower BBC in used RMS. Implications for these findings are that producers should strive to put clean and high DM fresh (RTU) bedding into stalls. Monitoring BBC and DM in RTU solids may be of value for producers using RMS bedding.

University of Missouri

Members: Pamela Adkins, John Middleton                                                                       

Contributors: Alyssa Novo

The University of Missouri has worked on novel techniques for use of MALDI-TOF to identify various strains of S. chromogenes.  This work will be used to see if strain level difference can explain variability in persistence and somatic cell count response within the mammary gland.

Rutgers University; New Jersey Agricultural Experiment

Member: Jeffrey Boyd

Contributors: Kylie Ryan Kaler, Gustavo Rios, Nupur Tyagi, Hannah Bovermann, Franklin Roman         

We have been assessing the activities of compounds that could be applied to decrease staphylococcal burden. We have discovered that starving staphylococcal cells for a sulfur source increases sensitivity to copper or silver ions and are determining the mechanism. We have also developed new nanoparticles containing chlorhexidine that are active against bacterial pathogens.

South Dakota State University

Members: T. Swartz

As mentioned under objective 1, we received funding from USDA-NIFA-AFRI to conduct experiments assessing the role of systemic inflammation on mammary gland immune responses. One of the aims in this study is to determine if the administration of a non-steroidal anti-inflammatory drug to postpartum dairy cows will improve mammary gland health. We have also received funding from a dairy nutrition company to investigate the role of a feed additive (direct-fed microbial) on immune function during an intramammary lipopolysaccharide challenge.

University of Vermont Agriculture Station

Members: Feng-Qi Zhao, John Barlow

The Barlow lab completed a field study exploring the associations between bedding management practices and milk quality, udder health, udder hygiene, and milk production outcomes on organic dairy farms in Vermont. Comparing 3 different housing and bedding systems on 21 enrolled farms, we found numeric differences that may be biologically important, including farms with deeper bedding had a lower BTSCC, lower newly elevated SCS, lower chronically elevated SCS, lower elevated current SCS, lower average SCS, and better udder hygiene metrics. Farms with lower mean udder hygiene scores had numerically lower chronically elevated SCS, lower elevated current SCS, and lower average SCS. We could not reject the null hypothesis that milk quality and udder health outcomes did not differ by facility type, and this does not preclude the existence of biological differences in these outcomes between facility types. We concluded that bedded packs may be a viable option for confinement housing during the winter nongrazing season for pasture-based herds interested in a loose-housing system in the northeastern United States.

WORK PLANNED FOR THE COMING YEAR, LISTED BY OBJECTIVE:

OBJECTIVE 1

University of Minnesota

Members: S. Godden, L. Caixeta, N. Noyes, B. Crooker

UMN researchers will submit a manuscript describing the host transcriptome and host-associated microbiome response to Escherichia coli infection in cows with modern host genetics and a special population of cows that continue to have bovine genetics from the 1960s. This study will reveal how the host genome, host transcriptome and host-associated microbiome interact during a mastitis pathogen challenge.

The Ohio State University

Members: B. Enger

Conduct LPS challenge studies in lactating cows to elucidate neutrophil dynamics in contemporary cattle.

OBJECTIVE 2

Cornell University

Members: Quinn Kolar, Matthias Wieland

We have a challenge studied planned for 2025 to assess the impact of mastitis on emissions and how that potentially ties to improved economic outcomes.

University of Minnesota

Members: S. Godden, L. Caixeta, N. Noyes, B. Crooker

UMN researchers will investigate the potential inhibitory mechanisms of Bacillus spp isolates against Staphylococcus aureus, with the goal of identifying mechanisms of inhibition at the genomic, transcriptomic, proteomic and/or metabolic levels.

University of Missouri

Members: Pamela Adkins, John Middleton

The University of Missouri will be working on evaluating if induced intramammary infections with different strains of S. chromogenes result in repeatable outcomes regarding quarter level somatic cell count.

Hill Farm Research Station, LSU AgCenter

Member: William E. Owens

Continuation of outreach activities.

Rutgers University; New Jersey Agricultural Experiment

Member: Jeffrey Boyd

Contributors: Kylie Ryan Kaler, Gustavo Rios, Nupur Tyagi, Hannah Bovermann, Franklin Roman

We will actively investigate how Staphylococcus aureus genetically regulates iron uptake and useage. We will investigate how copper and silver ions kill S. aureus and determine if these metal ions are synergistic with alternate antimicrobials

University of Vermont Agriculture Station

Members: Feng-Qi Zhao, John Barlow

The Barlow lab, in a collaboration with the University of Missouri, will explore the associations between genetic markers of virulence and mastitis severity and persistence for Staphylococcus chromogenes.

OBJECTIVE 3

University of Minnesota

Members: S. Godden, L. Caixeta, N. Noyes, B. Crooker

Our plans for objective 3 in the next year are as follows:

Relationships between method of processing and presence of mastitis and non-mastitis pathogens in ready-to-use recycled manure solids bedding on Midwest dairy farms. F. Peña-Mosca, S. Godden, E. Royster, D. Albrecht, S. Wells, B.A. Crooker and N. Aulik.

This study investigated associations between recycled manure solids (RMS) processing systems, used alone or in combination, on the presence of important pathogens affecting dairy cattle health. Our results showed that when used as a stand-alone processing technique, anaerobic digestion or secondary processing methods (e.g. composting or drying) reduced the counts of mastitis pathogens and reduced, and reduced, but did not completely eliminate the risk of Mycobacterium avium subspecies paratuberculosis and Salmonella spp. in ready-to-use recycled RMS samples. However, combining anaerobic digestion with a secondary processing method led to the greatest reduction in mastitis pathogen counts and completely eliminated Mycobacterium avium subspecies paratuberculosis and Salmonella spp. in RMS samples. Further research is needed to confirm these findings, to assess cost-benefit, and to examine how different processing system combinations may influence the presence of other pathogens significant to animal health. The results of this study will be submitted for peer-review and publication in early 2025.

University of Missouri

Members: Pamela Adkins, John Middleton

The University of Missouri will be working on evaluation of the protective capacity of S. chromogenes on the teat end through a challenge trial done in heifers. The work will evaluate if the presence of this organism is protective.

South Dakota State University

Members: T. Swartz

Determine if the administration of a non-steroidal anti-inflammatory drug to postpartum dairy cows will improve mammary gland health. Investigate the role of a feed additive (direct-fed microbial) on immune function during an intramammary lipopolysaccharide challenge.

University of Vermont Agriculture Station

Members: Feng-Qi Zhao, John Barlow

The Barlow lab will conduct studies characterizing the teat skin microbiome and exploring the teat skin microbiota as a source of inhibitors of major mastitis pathogens such as Staphylococcus aureus.

Peer-Reviewed Literature

Cornell University

1. Kolar, Q. K., Godden, S. M., Erskine, R. J., & Ruegg, P. L. (2024). Confirmed bacteriological diagnosis and cure of non-severe Gram-positive clinical mastitis cases enrolled in a randomized clinical trial based on results of on-farm culture. JDS Communications.
2. Kolar, Q. K., Goncalves, J. L., Erskine, R. J., & Ruegg, P. L. (2024). Comparison of minimum inhibitory concentrations of selected antimicrobials for non-aureus Staphylococci, Enterococci, Lactococci, and Streptococci isolated from milk samples of cows with clinical mastitis. Antibiotics, 13(1), 91.
3. Wieland M, Skarbye AP. A retrospective cohort study investigating the association of individual quarter dry-off with udder health, milk production, and culling risk. J Dairy Sci, 2024, 107:4941-4960

University of Minnesota

4. Dean, C.J., Deng, Y., Wehri, T.C., Pena Mosca, F., Ray, T., Crooker, B.A., Godden, S.M., Caixeta, L.S., Noyes, N.R. The impact of kit, environmental and sampling contamination on the observed microbiome of bovine milk. mSystems 9:e01158-23 2024. https://doi.org/10.1128/msystems.01158-23
5. Florentino, C.C. &, F. Peña-Mosca, M. Ruch, E. Shepley, M. Barbosa, D. Moreira, M. Mahmoud, L. Tikosky, W. Knauer, G. Cramer, S. Godden, L. Caixeta. 2024. Randomized clinical trial evaluating the effects of administering acidogenic boluses at dry-off on udder health, milk yield, and herd removal. J. Dairy Sci. 107:3899–3915 https://doi.org/10.3168/jds.2023-23757
6. Dean, C. &, F. Peña-Mosca, T. Ray, T. Wehri, K. Sharpe, A. Antunes Jr, E. Doster, L. Fernandes, V. Calles, C. Bauman, S. Godden, B. Heins, P. Pinedo, V. Machado, L. Caixeta, and N. Noyes. 2024. Exploring associations between the teat apex metagenome and Staphylococcus aureus intramammary infection risk in primiparous cows under organic directives. AppEnvirMicro 90:1-23 https://doi.org/10.1128/aem.02234-23
7. Peña-Mosca, F. &, S. Godden, E. Royster, B.A. Crooker, and J. Timmerman. 2024. Methods of processing recycled manure solids bedding on Midwest dairy farms II: Relationships between bedding characteristics and bedding bacteria count. Bov Pract. 58:8-18
8. Brink, A.A. &, W.J. Weber, J.D. Lippolis, J.B. Cole, A.K. Rendahl, L. Caixeta, S.M. Godden, A.J. Seykora, and B.A. Crooker. 2023. Effect of Holstein genotype on ex-vivo interleukin-1β response to lipopolysaccharide (LPS), lipoteichoic acid (LTA) and heat-killed Gram-negative and Gram-positive bacteria. Vet Imm & Immunopathology. 258:110573 https://doi.org/10.1016/j.vetimm.2023.110573
9. de Jong, E. L. Creytens, S. De Vliegher, K. McCubbin, M. Baptiste, A.A. Leung, D. Speksnijder, S. Dufour, J. Middleton, P.L. Ruegg, T.J.G.M. Lam, D.F. Kelton, S. McDougall, S.M. Godden, A. Lago, P.J. Rajala-Schultz, K. Orsel, V. Krömker, J.P. Kastelic, and H.W. Barkema. 2023. Selective treatment of non-severe clinical mastitis does not negatively affect cure, somatic cell count, milk yield, recurrence and culling: a systematic review and meta-analysis. J Dairy Sci 106:1267-1286 https://doi.org/10.3168/jds.2022-22271

University of Missouri

10. Haw SR, Adkins PRF, Bernier Gosselin V, Poock SE, Middleton JR. 2024. Intramammary infections in lactating Jersey cows: prevalence of microbial organisms and association with milk somatic cell count and persistence of infection. J Dairy Sci.107 (5): 3157-3167. DOI: 10.3168/jds.2023-23848

The Ohio State University

11. Gammariello, C. S., J. Hanson, A. E. Relling, M. X. S. Oliveira, A. Sipka, K. M. Enger, and B. D. Enger. 2024. Localized mammary gland changes in milk composition and venous blood metabolite concentrations result from sterile subclinical mastitis. J. Dairy Sci. 107:6148-6160. https://doi.org/10.3168/jds.2023-24044.

Rutgers University; New Jersey Agricultural Experiment

12. Muneeswaran Z.P., Teoman B., Wang Y., Chaudhry H., Brinzari T.V., Verma G., Ranasinghe L., Ryan Kaler K.M., Huang K., He, X., Thomas B.L., Xu S., Cheng C.Y., Boyd J.M., Chen D., Hao Z., Ma S., Asefa T., Pan L., Dubovoy V., Novel anionic surfactant-modified chlorhexidine and its potent antimicrobial properties. 12/2023 Dalton Transactions PMID: 38224288.

South Dakota State University

13. Swartz, T. H.*, B. J. Bradford, L. K. Mamedova, and K. A. Estes. 2024. Effects of dietary rumen-protected choline supplementation to periparturient dairy cattle on inflammation and metabolism in mammary and liver tissue during an intramammary lipopolysaccharide challenge. J. Dairy Sci. 107:1211-1227. https://doi.org/10.3168/jds.2023-23752
14. Swartz, T. H., B. J. Bradford, L. K. Mamedova, and K. A. Estes. 2023. Effects of dietary rumen-protected choline supplementation to periparturient dairy cattle on inflammation, metabolism, and performance during an intramammary lipopolysaccharide challenge. J. Dairy Sci. 106:8561-8582. https://doi.org/10.3168/jds.2023-23259

University of Vermont Agriculture Station

15. Chrissy Lalonde, Jana Kraft, and Feng-Qi Zhao. (2024). Review: Molecular aspects of milk lipid synthesis and secretion in mammary epithelial cells. Animal Nutriomics, in press. doi: 10.1017/anr.2024.19
16. Miyuki Takashima, Masahiro Kurita, Haruhi Terai, Feng-Qi Zhao, and Jun-ichiro Suzuki. (2024). S-allylmercaptocysteine inhibits lipopolysaccharide-induced inflammation via altering phosphorylation of spliceosomal components in mammary epithelial cell. Scientific Reports, in press
17. Yongxin Li, Ning Han, Pengfei Hou; Feng-Qi Zhao, Hongyun Liu. (2024). Roles of MAPK and Nrf2 signaling pathways in quercetin alleviating redox imbalance induced by hydrogen peroxide in mammary epithelial cells. Animal Nutriomics 1, e1, 1–10. doi: 10.1017/anr.2024.2
18. Jeffrey, C. E.c, Andrews, T., Godden, S. M., Neher, D. A., Barlow, J. W.a (2024). Relationship between facility type and bulk tank milk bacteriology, udder health, udder hygiene, and milk production on Vermont organic dairy farms. Journal of Dairy Science, 107(10), 8534–8553. https://doi.org/10.3168/jds.2023-24576 Product of USDA-NIFA-OREI award number 2018-51300-28561 and USDA-NIFA-Predoctoral Fellowship award number 2022-67011-3656
19. Chakrawarti, A.c, Eckstrom, K., Laaguiby, P., Barlow, J.W.a 2024. Hybrid Illumina-Nanopore assembly improves identification of multilocus sequence types and antimicrobial resistance genes of Staphylococcus aureus isolated from Vermont dairy farms: comparison to Illumina-only and R9.4.1 nanopore-only assemblies. Access Microbiology https://doi.org/10.1099/acmi.0.000766.v3 Product of USDA-Hatch Vermont Experiment Station project (multi-state project NE1748, award number VT-H02413MS) and Vermont Animal Health Formula Funds (awards VT-AH02703 and VT-2023-AH01).
20. Chakrawarti, A.c, Casey, C.L., Burke, A.d, Mugabi, R.c, Ochoa, A., Barlow, J.W.a 2024. An observational study demonstrates human-adapted Staphylococcus aureus strains have a higher frequency of antibiotic resistance compared to cattle-adapted strains isolated from dairy farms making farmstead cheese. BMC Veterinary Research 20:75 DOI: 10.1186/s12917-024-03910-6 Product of USDA-Hatch Vermont Experiment Station project (multi-state project NE1748, award number VT-H02413MS).

Abstracts

Cornell University

1. Somula H, Singh A, Spellman ME, Wieland M. The effect of individual quarter dry-off on milk production, occurrence of mastitis, and culling risk in Holstein dairy cows. 32^nd World Buiatrics Congress, Cancun, Mexico, 2024

University of Minnesota

2. C.C., W. Knauer*, L. Tikofsky, S.M. Godden, L. Caixeta, F. Peña-Mosca, D. Nydam. 2024. Randomized clinical trial evaluating the effects of the administration of acidogenic boluses on the day prior to dry-off on dairy cow welfare. AABP 27^th Annu Conference. Columbus, OH. Sept 12-14, 2024

University of Missouri

3. Isensee PK, Adesola RO, and Adkins PRF. Characterization of antibacterial activity and strain variability of Staphylococcus chromogenes isolates originating from dairy cattle. MU CVM Research Day. May 3, 2024.
4. Novo A and Adkins PRF. Intramammary infections in primigravid and nulligravid dairy heifers. MU CVM Research Day. May 3, 2024.
5. Novo A and Adkins PRF. Evaluation of intramammary infection status in dairy heifers. Proceedings of the 63rd Annual Meeting of the National Mastitis Council, Dallas, Texas, Jan 29 – Feb 1, 2024.
6. Isensee PK, Adesola RO, and Adkins PRF. Characterization of antibacterial activity and strain variability among Staphylococcus chromogenes isolates originating from dairy cattle. Proceedings of the 63rd Annual Meeting of the National Mastitis Council, Dallas, Texas, Jan 29 – Feb 1, 2024.
7. Adkins PRF, Adesola RO, and Barlow JW. Using MALDI-TOF mass spectrometry to determine Staphylococcus chromogenes strain types. Conference of Research Workers in Animal Diseases. Chicago, IL. Jan 21-24, 2024.

The Ohio State University

8. X. S. Oliveira, K. M. Enger, and B. D. Enger. 2024. Impact of Staphylococcus aureus intramammary infection on mammary cell proliferation in pregnant heifers. J. Dairy Sci. 107: (Suppl. 1):106-107.
9. Enger, K. M., S. Park, A. E. Relling and B. D. Enger. 2024. Mineral composition of whole milk from mammary glands repeatedly challenged with killed Staphylococcus aureus. J. Dairy Sci. 107: (Suppl. 1):312.
10. Enger, B. D., G. Hastings, C. S. Gammariello, M. X. S. Oliveria, and K. M. Enger. 2024 Effects of repeated infusions of killed Staphylococcus aureus on milk yield and composition. J. Dairy Sci. 107:(Suppl. 1):106.
11. Enger, B.D., M. X. S. Oliveria, P. H. Baker, C. S. Gammariello, K. M. Enger. M. A. McGuire, and J. Williams. 2024. Intramammary infections in primigravid heifer mammary glands during progressing stages of gestation. Page 324 in Conf. of Res. Workers in Animal Dis. Proc.
12. Oliveira, M.X.S., C.S. Gammariello, P.H. Baker, K.M. Enger, D.D., Clevenger, S.K. Jacobi, N.M. Bello, and B.D. Enger. 2024. Impact of intramammary infections to the developing mammary tissue of dairy heifers at different stages of pregnancy. Pages 95-96 in Natl. Mastitis Counc. Annu. Mtg. Proc., Dallas, TX, Natl. Mastitis Council Inc., New Prague, MN.

Rutgers University; New Jersey Agricultural Experiment

13. Gustavo Rios, Boyd J.M. Assessing the role of the Fur-regulated sRNA Tsr25 during Staphylococcus aureus response to iron scarcity. Initiative for maximizing student development, Rutgers University, Piscataway, NJ 10/2023.
14. Tyagi N., and Boyd J.M. Determining how itaconic acid modulates Staphylococcus aureus physiology. New Jersey American Society of Microbiology Meeting in Miniature (Theobald Smith Society). New Brunswick, NJ 4/2024.

South Dakota State University

15. Celemin Sarmiento, A., B. J. Bradford, L. K. Mamedova, and T. H. Swartz. The effects of dietary rumen-protected choline on mammary DNA methylation patterns. American Dairy Science Association. West Palm Beach, FL. June 16-19, 2024.
16. Bulnes, M. A. Celemin Sarmiento, M. R. A. Redoy, J. Lefler, C. Marotz, M. Embree, T. H. Swartz, and M. E. Uddin. Effects of dietary rumen-derived microbial product supplementation on lactation performance and enteric methane emission in lactating dairy cows. American Dairy Science Association. West Palm Beach, FL. June 16-19, 2024.
17. Bulnes, M. A. Celemin Sarmiento, M. R. A. Redoy, J. Lefler, C. Marotz, M. Embree, T. H. Swartz, and M. E. Uddin. Effects of dietary rumen-derived microbial product supplementation on rumen fermentation in lactating dairy cows. American Dairy Science Association. West Palm Beach, FL. June 16-19, 2024.

University of Vermont Agriculture Station

18. Lalonde C, Kraft J, Zhao F-Q (2024) Supplementing cell culture media with essential fatty acids alters the response of MAC-T cells to inflammatory mediators in triacylglyceride synthesis. ADSA Annual Meeting 2024.
19. Barlow, J., Adrian, R., Chakrawarti, A., Jeffrey, C.E., Mugabi, R, Ochoa, A., Machado de Sant’Anna, F., Munk, P. 2024. Case Study: Genetic characterization of methicillin and lincosamide resistant Mammaliicoccus fleurettii isolated from cattle and humans on a Vermont organic dairy farm. National Mastitis Council Regional meeting, Ghent, Belgium, August 11-13.
20. Barlow, J., Chakrawarti, A., Jeffrey, C.E., Machado de Sant’Anna, F., Munk, P. 2024. Use of Flankophile pipeline to infer antimicrobial resistance gene synteny among mastitis pathogens: 3 examples. Mastitis Research Workers annual meeting, Ghent, Belgium, August 8-9.
21. Jeffrey, C.E., Adkins, P.R.F, Barlow, J.W. 2024. Prevalence and Effect on Somatic Cell Count of Non-aureus Staphylococci and Mammaliicocci Intramammary Infections on Organic Dairies in Vermont. Proceedings of National Mastitis Council, 63thrd Annual Meeting, Dallas, TX January 29 – February 1.

Conference Proceedings

University of Minnesota

1. Bedding selection and management: An important determinant in producing quality milk. Upper Midwest Dairy Industry Assoc. (UMDIA). St. Cloud, MN. 09/26/2024
2. Preconference Seminar: Understanding the impacts of switching to various forms of solids bedding on herd health, operations, and the environment. 57^th Annu Conf Am Assoc. Bov Pract. Sept. 11, 2024. Columbus, OH. Two presentations:
   1. Sand bedding: Benefits, monitoring and management
   2. Recycled manure solids bedding: Pros/Cons, monitoring and managagement
3. Methods of processing recycled manure solids bedding on Midwest dairy farms II: Relationships between bedding characteristics and bedding bacteria count. AABP. 01/29/2024
4. WVMA. Management of recycled manure solids bedding. 11/3/23

University of Missouri

5. Adkins PRF. Tools and tips for diagnosing intramammary infections. NMC Regional Meeting. Ghent, Belgium. Aug 12-14, 2024.
6. Middleton JR and Adkins PRF. Mastitis diagnosis: what’s the goal? Proceedings of the 63rd Annual Meeting of the National Mastitis Council, Dallas, Texas, Jan 29 – Feb 1, 2024.

South Dakota State University

7. Swartz, T. H. 2024. Nutrition, Metabolism, and Mastitis. National Mastitis Council Regional Meeting Proceedings.

University of Vermont Agriculture Station

8. Barlow, J. 2024. “Antibiotic resistance genes, cows, and fermented food: Antimicrobial resistance and resistomes on dairy farms in Vermont.” International Conference on the Science of Artisan Cheese. August, Somerset, England.

Poster Presentations

Cornell University

1. Somula H, Singh A, Spellman ME, Wieland M. The effect of individual quarter dry-off on milk production, occurrence of mastitis, and culling risk in Holstein dairy cows. 32nd World Buiatrics Congress, Cancun, Mexico, May 20th – 24th, 2024

Rutgers University; New Jersey Agricultural Experiment

2. Paola Garay Maris, Gustavo Rios, Boyd J.M.  Staphylococcus aureus iron usage: characterization of a novel antibiotic target. National meeting for the Society for the Advancement of Chicanos/Hispanics and Native Americans in Science. Portland OR. 10/2023.
3. Norambuena J. and Boyd J.M.  Unravelling copper toxicity mechanisms in Staphylococcus aureus”. Reunión anual de la Sociedad de Bioquímica y Biología Molecular de Chile, Coquimbo, Chile. 10/2023.
4. Leon G. Leanse, Boyd J.M. et al., Unravelling the antimicrobial mechanisms of blue light. Photonic Diagnosis, Monitoring, Prevention, and Treatment of Infections and Inflammatory Diseases, San Francisco, CA. 2/2024.
5. Tyagi N., and Boyd J.M. Determining how itaconic acid modulates Staphylococcus aureus physiology. New Jersey American Society of Microbiology Meeting in Miniature (Theobald Smith Society). New Brunswick, NJ 4/2024.
6. Tyagi N., Wong T., and Boyd J.M. Determining how itaconic acid modulates Staphylococcus aureus physiology. New Jersey American Society of Microbiology Meeting in Miniature (Theobald Smith Society). New Brunswick, NJ 4/2024.
7. Naidu N., Chen S., Rios-Delgado G., Boyd J.M. Exploring Fur and IsrR genetic regulation in Staphylococcus epidermidis. New Jersey American Society of Microbiology Meeting in Miniature (Theobald Smith Society). New Brunswick, NJ 4/2024.
8. Bovermann H., Boyd J.M. Impact of Sulfur Metabolism on Copper and Silver homeostasis in Staphylococcus aureus. Rutgers Microbiology symposium, Rutgers University, New Brunswick, NJ 4/2024.
9. Naidu N., Chen S., Rios-Delgado G., Boyd J.M. Exploring Fur and IsrR genetic regulation in Staphylococcus epidermidis. Rutgers Microbiology symposium, Rutgers University, New Brunswick, NJ 4/2024.
10. Tyagi N., Wong T., and Boyd J.M. Determining how itaconic acid modulates Staphylococcus aureus physiology. Rutgers Microbiology symposium, Rutgers University, New Brunswick, NJ 4/2024.
11. Vincent Zheng, Rios-Delgado G., and Boyd J.M. The Relationship Between Iron Homeostasis and Biofilm Formation in S. epidermidis. Rutgers Microbiology symposium, Rutgers University, New Brunswick, NJ 4/2024.
12. Rios-Delgado G. and Boyd J.M. et al., Fur-regulated small RNA IsrR represses TCA cycle during iron limitation in Staphylococcus aureus. International meeting on Fe-S proteins: Function, Biogenesis, and Regulation. Wake Forest University, Winston-Salem, NC 6/2024.
13. Rios-Delgado G., Boyd J.M., et al., Fur-regulated small RNA IsrR represses TCA cycle during iron limitation in Staphylococcus aureus. International meeting on Fe-S proteins: Function, Biogenesis, and Regulation. Wake Forest University, Winston-Salem, NC 6/2024.