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Betsy M. Karle

Dairy Advisor & County Director
UC Cooperative Extension Glenn County
821 E. South Street
Orland, CA 95963
(530) 865-1156
bmkarle@ucanr.edu Create VCard

Also in:
Butte County
Tehama County
Shasta County
Sutter-Yuba Counties
Yolo County
Capitol Corridor MCP Cooperative Extension
Siskiyou County
Colusa County
Sacramento County
Solano County


M.S. Ecology, UC Davis. 2003
B.S. Agriculture Systems & Environment, UC Davis. 1999



Dairy Science


preweaned calf management, antimicrobial stewardship, environmental sustainability

Areas of Expertise (click to see all ANR academics with this expertise)


Peer Reviewed

  • Garzon, A. (2023). Antimicrobial stewardship on the dairy: Evaluating an on-farm framework for training farmworkers. Journal of Dairy Science. 106:6, 4171-4183.
  • Breen, M.J.; Abdelfattah, E.M., et al. (2023). Effect of Group Housing of Preweaned Dairy Calves: Health and Fecal Commensal Antimicrobial Resistance Outcomes. Antibiotics. 12:6, 1019.
  • Basbas, C.; Aly, S., et al. (2022). Effect of Intramammary Dry Cow Antimicrobial Treatment on Fresh Cow's Milk Microbiota in California Commercial Dairies. Antibiotics. 11, 963.
  • Aly, S.S.; Okello, E., et al. (2022). Effectiveness of Intramammary Antibiotics, Internal Teat Sealants, or Both at Dry-Off in Dairy Cows: Clinical Mastitis and Culling Outcomes. Antibiotics. 11, 954.
  • Basbas, C; Garzon, A, et al. (2022). Evaluation of antimicrobial resistance and risk factors for recovery of intrauterine Escherichia coli from cows with metritis on California commercial dairy farms. Scientific Reports. 12, 13937.
  • Abdelfattah, E.M.; Ekong, P.S., et al. (2022). Factors Associated with Antimicrobial Stewardship Practices on California Dairies: One Year Post Senate Bill 27. Antibiotics. 11:2, 165-171. January 25, 2022. https://www.mdpi.com/2079-6382/11/2/165
  • Miller, C.; Meyer, D., et al. (2022). Forage Harvested for Silage: Methods to Measure Yield and Nitrogen Composition. UC ANR 8000 Series. 8713. https://anrcatalog.ucanr.edu/pdf/8713.pdf
  • Miller, C.; Meyer, D., et al. (2022). Methods for Collecting Representative Samples of Solid Manure for Nitrogen Analysis. UC ANR 8000 Series. 8715. https://anrcatalog.ucanr.edu/pdf/8715.pdf
  • Cheong, S.; Francesco, J.D., et al. (2022). Survey of Management Practices and Farmers’ Perceptions of Diseases on Organic Dairy Cattle Farms in California. Animals. 12, 2526.
  • Ekong, P.S.; Abdelfattah, E.M., et al. (2021). 2018 Survey of antimicrobial drug use and stewardship practices in adult cows on California dairies: Immediate Post-Senate Bill 27 Impact. Peer J.
  • Ekong, P.S.; Abdelfattah, E.M., et al. (2021). 2018 Survey of antimicrobial drug use and stewardship practices in adult cows on conventional California dairies: post-Senate Bill 27. Peer J. 10:7717, 11515.
  • Abdelfattah, Essam; Ekong, Pius, et al. (2021). 2019 Survey of Antimicrobial Drug Use and Stewardship Practices in Adult Cows on California Dairies: Post Senate Bill 27. Microorganisms. 2021:9, 1507.
  • Abdelfattah, E.M.; Ekong, P.S., et al. (2021). Epidemiology of antimicrobial resistance (AMR) on California dairies: descriptive and cluster analyses of AMR phenotype of fecal commensal bacteria isolated from adult cows. Peer J. 9:e11108. https://peerj.com/articles/11108/#
  • Cella, Elisa; Okello, Emmanuel, et al. (2021). Estimating the Rates of Acquisition and loss of Resistance of Enterobacteriaceae to Antimicrobial Drugs in Pre-Weaned Dairy Calves. Microorganisms. 2021:9, 2103.
  • Maier, G.U.; Love, W.J., et al. (2020). A novel Risk Assessment tool for Bovine Respiratory Disease in preweaned dairy calves. Journal of Dairy Science. 103:10, 9301-9317.
  • Aly, S.S.; Karle, B.M., et al. (2020). Components of a risk assessment tool for prevention and control of bovine respiratory disease in preweaned dairy calves. Animal Health Research Reviews. 21:2, 153-159. December 2020.
  • Dubrovsky, S.A.; Van Eenenaamm, A.L., et al. (2020). Preweaning cost of bovine respiratory disease (BRD) and cost-benefit of implementation of preventative measures in calves on California dairies: The BRD 10K study. Journal of Dairy Science. 103:2, 1583-1597.
  • Li, X.; Jackson, W., et al. (2019). A Cross-Sectional Study of prevalence and Species of Cryptosporidium spp. in Preweaned Calves and Associated Management Risk Factors on Dairies in Central California, USA. J Vet Med Res. 6:1, 1171-1180. January 24. https://www.jscimedcentral.com/VeterinaryMedicine/veterinarymedicine-6-1171.pdf
  • Dubrovsky, S.A.; Van Eenennaam, A.L., et al. (2019). Bovine respiratory disease (BRD) cause-specific and overall mortality in preweaned calves on California dairies: The BRD 10K study. Journal of Dairy Science. 102:8, 7320-7328.
  • Maier, Gabriele U.; Rowe, Joan D., et al. (2019). "Development of a clinical scoring system for bovine respiratory disease in weaned dairy calves." Journal of Dairy Science 102(8): 7329-7344.
  • Dubrovsky, S. A.; Van Eenennaam, A. L., et al. (2019). "Epidemiology of bovine respiratory disease (BRD) in preweaned calves on California dairies: The BRD 10K study." Journal of Dairy Science 102(8): 7306-7319.
  • Belmar, M.; Aly, S.S., et al. (2019). Evaluation of four commercial tests for detecting ceftiofur in waste milk bulk tank samples. Plos One. 14:11. November 12, 2019.
  • Hagey, Jill V.; Bhatnagar, Srijak, et al. (2019). "Fecal Microbial Communities in a Large Representative Cohort of California Dairy Cows." Frontiers in Microbiology 10(1093)
  • Maier, G. U.; Love, W. J., et al. (2019). "Management factors associated with bovine respiratory disease in preweaned calves on California dairies: The BRD 100 study." Journal of Dairy Science 102(8): 7288-7305.
  • Martins, J. P. N.; Karle, B. M., et al. (2019). "Needs assessment for cooperative extension dairy programs in California." Journal of Dairy Science 102(8): 7597-7607.
  • Miller, Christine M.; Heguy, Jennifer M., et al. (2019). Optimizing accuracy of sampling protocols to measure nutrient content of solid manure. Waste Management. 85, 121-130. 2/15/19.
  • Karle, B. M.; Maier, G. U., et al. (2019). "Regional management practices and prevalence of bovine respiratory disease in California's preweaned dairy calves." Journal of Dairy Science 102(8): 7583-7596.
  • Meyer, D.; Karle, B.M., et al. (2019). UC-industry-agency partnerships influence and help implement dairy water quality policy. California Agriculture. 73:1, 40-47. http://calag.ucanr.edu
  • Tempini, PN; Aly, SS, et al. (2018). Multidrug residues and antimicrobial resistance patterns in waste milk from dairy farms in Central California. Journal of Dairy Science. 101:9, 8110-8122. September 1, 2018.
  • Miller, Christine M.; Fadel, James G., et al. (2018). Optimizing accuracy of protocols for measuring dry matter and nutrient yield of forage crops. Science of the Total Environment. 624, 180-188. May 15, 2018.
  • Love, W. J.; Lehenbauer, T. W., et al. (2016). "Survey of management practices related to bovine respiratory disease in preweaned calves on California dairies." Journal of Dairy Science 99(2): 1483-1494.
  • Davy, J.S.; Karle, B.M., et al. (2015). "Broadleaf weed control in irrigated pasture containing Trifolium repens." Crop and Pasture Science 66: 985-991.
  • Meyer, D.; Price, P., et al. (2011). "Survey of dairy housing and manure management practices in California." Journal of Dairy Science 94: 4744-4750.
  • Harter, T.; Atwill, E.R., et al. (2008). "Developing risk models of Cryptosporidium transport in soils from vegetated, tilted soil box experiments." Journal of Environmental Quality 37: 245-258.
  • Lewis, D.J.; Atwill, E.R., et al. (2005). "Linking on-farm dairy management practices to storm-flow fecal coliform loading for California coastal watersheds." Environmental Monitoring and Assessment 107: 407-425.
  • Lile, D.; Tate, K.W., et al. (2003). "Stubble height standards for Sierra Nevada meadows can be difficult to meet." California Agriculture 57: 60-64.
  • Atwill, E.R.; Hou, L., et al. (2002). "Transport of Cryptosporidium parvum oocysts through vegetated buffer strips and estimated filtration efficiency." Applied and Environmental Microbiology 68: 5517-5527.

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