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Bovine respiratory disease (BRD) is the primary disease of concern to beef production and is driven by stress, bacteria, viruses, and environmental and management practices. Antimicrobial use (AMU) to control BRD selects for antimicrobial resistance (AMR) genes (ARGs). Treatment failure due to AMR necessitates a rapid switch to an effective antimicrobial before a devastating amount of death loss occurs. Monitoring AMR in a herd through individual animals is impractical. There is a need for a fast, pragmatic, and scalable methodology to monitor AMR within cattle to guide effective AMU. Cattle watering bowls (WB) have been previously shown to harbour BRD pathogens and ARGs but have yet to be explored in the same context as wastewater AMR monitoring is for public health. This thesis outlines a pilot project of WB sampling as a proxy method to monitor the presence of ARGs of relevance to BRD associated pathogens. The microbiomes within watering bowls of two feedlots were genotypically and phenotypically assessed through water, swab, and sediment sampling. A new feedlot was sampled (68 water, 63 swab) as pens filled (up to 9 WB) over a series of 8 weeks. The other, older, feedlot was only sampled in the 8th week (sediment, swab, water) from 20 WB. For phenotypic AMR detection, samples were inoculated into antimicrobial sensitivity test (AST) panels containing microdilutions of four antimicrobials (enrofloxacin, florfenicol (FFN), tulathromycin, oxytetracycline). Bacteria that grew on these plates were isolated (n = 78). A subset (n = 28 new feedlot, n = 3 old feedlot + H. somni from a deep nasopharyngeal swab) of …