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There is a dual effect of air sterilization and promotion of vitamin D synthesis for the specific bands of ultraviolet light. This study investigated the potential use of A-band ultraviolet (UVA) tubes as a clean and safe way of reducing airborne bacteria and improving calf health. The composition and emission characteristics of airborne bacteria were investigated and used to determine the correct operating regime of UVA tubes in calf houses. Intermittent exceedances of indoor airborne bacteria were observed in closed calf houses. The measured emission intensity of airborne bacteria was 1.13 \u00b1 0.09 \u00d7 107 CFU h\u22121 per calf. Proteobacteria were the dominant microbial species in the air inside and outside calf houses. After UVA radiation, the indoor culturable airborne bacteria decreased in all particle size ranges of the Anderson sampler, and it showed the highest reduction rate in the size range of 3.3\u20134.7 \u03bcm. The results of this study would enrich the knowledge of the source characteristics of the airborne bacteria in intensive livestock farming and contribute to the environmental control of cattle in intensive livestock production.<\/jats:p>","DOI":"10.3390\/microorganisms12071472","type":"journal-article","created":{"date-parts":[[2024,7,19]],"date-time":"2024-07-19T13:12:57Z","timestamp":1721394777000},"page":"1472","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Clean and Health-Care-Focused Way to Reduce Indoor Airborne Bacteria in Calf House with Long-Wave Ultraviolet"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1451-557X","authenticated-orcid":false,"given":"Luyu","family":"Ding","sequence":"first","affiliation":[{"name":"Information Technology Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China"},{"name":"National Engineering Research Center for Information Technology in Agriculture (NERCITA), Beijing 100097, China"},{"name":"National Innovation Center of Digital Technology in Animal Husbandry, Beijing 100097, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qing","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Agricultural Structure and Bioenvironmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9415-8527","authenticated-orcid":false,"given":"Chaoyuan","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Agricultural Structure and Bioenvironmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunxia","family":"Yao","sequence":"additional","affiliation":[{"name":"Information Technology Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China"},{"name":"National Engineering Research Center for Information Technology in Agriculture (NERCITA), Beijing 100097, China"},{"name":"National Innovation Center of Digital Technology in Animal Husbandry, Beijing 100097, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Feifei","family":"Shan","sequence":"additional","affiliation":[{"name":"Intelligent Equipment Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qifeng","family":"Li","sequence":"additional","affiliation":[{"name":"Information Technology Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China"},{"name":"National Engineering Research Center for Information Technology in Agriculture (NERCITA), Beijing 100097, China"},{"name":"National Innovation Center of Digital Technology in Animal Husbandry, Beijing 100097, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.envpol.2009.07.011","article-title":"Airborne particulate matter from livestock production systems: A review of an air pollution problem","volume":"158","author":"Aarnink","year":"2010","journal-title":"Environ. 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