Skip to main content Accessibility help

Bacterial concentrations in bedding and their association with dairy cow hygiene and milk quality

  • I. Robles (a1), D. F. Kelton (a2), H. W. Barkema (a3), G. P. Keefe (a4), J. P. Roy (a5), M. A. G. von Keyserlingk (a6) and T. J. DeVries (a1)...


Comparison of bacterial counts (BCs) among common bedding types used for dairy cows, including straw, is needed. There is concern that the microbial content of organic bedding is elevated and presents risks for dairy cow udder health and milk quality. The objectives of this study were to investigate: (1) % DM and BCs (Streptococcus spp., all gram-negatives and specifically Klebsiella spp.) in different types of bedding sampled, and to investigate housing and farm management factors associated with % DM and BCs; (2) if bedding type was associated with hygiene of cow body parts (lower-legs, udder, upper-legs and flank) and housing and management factors associated with hygiene and (3) bedding types associated with higher BCs in cow milk at the farm level and bulk tank milk and management factors that were associated with highest BCs. Seventy farms (44 free-stall and 26 tie-stall) in Ontario, Canada were visited 3 times, 7 days apart from October 2014 to February 2015. At each visit, composite samples of unused and used bedding were collected for % DM determination and bacterial culture. Used bedding samples were collected from the back third of selected stalls. Data were analyzed using multivariable linear mixed models. Bedding classification for each farm were: new sand (n = 12), straw and other dry forage (n = 33), wood products (shavings, sawdust; n = 17) and recycled manure solids (RMSs)-compost, digestate (n = 8). In used bedding, across all bedding samples, sand was driest, compared to straw and wood, and RMS; higher % DM was associated with lower Streptococcus spp. count. Streptococcus spp. and all Gram-negative bacteria counts increased with increasing days since additional bedding was added. Gram-negative bacteria counts in used bedding varied with type: RMS = 16.3 ln colony-forming units (cfu)/mL, straw = 13.8 ln cfu/mL, new sand = 13.5 ln cfu/mL, and wood = 10.3 ln cfu/mL. Klebsiella spp. counts in used bedding were lower for wood products (5.9 ln cfu/mL) compared to all other bedding types. Mean cow SCC tended to be higher on farms with narrower stalls. Farms with mattress-based stalls had a higher prevalence of cows with dirty udders compared to those using a deep bedding system (often inorganic sand). Wider stalls were associated with lower bulk milk bacteria count. Lower % DM of used bedding was associated with higher bulk milk bacteria count. In conclusion, bedding management may have a profound impact on milk quality, bacterial concentrations in the bedding substrates, and cow hygiene.


Corresponding author


Hide All
Aghamohammadi, M, Haine, D, Kelton, DF, Barkema, HW, Hogeveen, H, Keefe, GP and Dufour, S 2018. Farm-level mastitis-associated costs on Canadian dairy farms. Frontiers in Veterinary Science 5, 112.
Altman, DG and Bland, JM 1995. Statistics notes: absence of evidence is not evidence of absence. BMJ 311, 485.
Barkema, HW, Schukken, YH, Lam, TJ, Beiboer, ML, Wilmink, H, Benedictus, G and Brand, A 1998. Incidence of clinical mastitis in dairy farms grouped in three categories by bulk milk somatic cell counts. Journal of Dairy Science 81, 411419.
Bello, NM and Renter, DG 2018. Invited review: reproducible research from noisy data: revisiting key statistical principles for the animal sciences. Journal of Dairy Science 101, 56795701.
Bernardi, F, Fregonesi, J, Veira, DM, Winkler, C, von Keyserlingk, MAG and Weary, DM 2009. The stall design paradox: neck rails increase lameness but improve udder and stall hygiene. Journal of Dairy Science 92, 30743080.
Bradley, A J, Leach, KA, Green, MJ, Gibbons, J, Ohnstad, IC, Black, DH, Payne, B, Prout, VE and Breen, JE 2018. The impact of dairy cows’ bedding material and its microbial content on the quality and safety of milk–A cross sectional study of UK farms. International Journal of Food Microbiology 269, 3645.
Canadian Bovine Mastitis and Milk Quality Research Network (CBMRN) 2010. Prevalence of clinical mastitis per pathogen per province. Retrieved on 16 March 2019 from
Canadian Council on Animal Care (CCAC) 2009. Guidelines on: the care and use of farm animals in research, teaching and testing. Retrieved on 13 October 2018 from
Canadian Dairy Information Centre. 2018. Dairy Barns by Type in Canada. Retrieved on 30 April 2019 from
Cole, KJ and Hogan, JS 2016. Short communication: environmental mastitis pathogen counts in freestalls bedded with composted and fresh recycled manure solids. Journal of Dairy Science 99, 15011505.
Cook, N 2002. The influence of barn design on dairy cow hygiene, lameness, and udder health. In Proceedings of the 35th Annual Convocation American Association Bovine Practitioners, 26–28 September 2002, Rome, GA, USA, pp. 97103.
Cook, NB and Reinemann, DJ 2007. A toolbox for assessing cow, udder and teat hygiene. In Proceedings of the 46th Annual Meeting National Mastitis Council, 21–24 January 2007, Madison, WI, USA, pp. 3133.
De Haas, Y, Veerkamp, RF, Barkema, HW, Gröhn, YT and Schukken, YH 2004. Associations between pathogen-specific cases of clinical mastitis and somatic cell count patterns. Journal of Dairy Science 87, 95105.
DeVries, TJ, Aarnoudse, MG, Barkema, HW, Leslie, KE and von Keyserlingk, MAG 2012. Associations of dairy cow behavior, barn hygiene, cow hygiene, and risk of elevated somatic cell count Journal of Dairy Science 95, 57305739.
Dohoo, I, Martin, SW and Stryhn, H 2009. Veterinary epidemiologic research. VER Inc., Charlottetown, PE, Canada.
Ellis, KA, Innocent, GT, Mihm, M, Cripps, P, Mclean, WG, Howard, CV and Grove-White, D 2007. Dairy cow cleanliness and milk quality on organic and conventional farms in the UK. Journal of Dairy Research 74, 302310.
Godden, S, Bey, R, Lorch, K, Farnsworth, R and Rapnicki, P 2008. Ability of organic and inorganic bedding materials to promote growth of environmental bacteria. Journal of Dairy Science 91, 151159.
Groot Antink, M 2009. Boxcompost voor koe in opmars. Veldpost 24, 17.
Harrison, E, Bonhotal, J and Schwarz, M 2008. Using Manure Solids as Bedding. Final Report. Cornell Waste Management Institute, Ithaca, NY. Retrieved on 06 March 2019 from
Hintze, J 2008. PASS 2008. NCSS, LLC, Kaysville, UT. Retrieved on 20 August 14 from
Hogan, JS and Smith, KL 1997. Bacteria counts in sawdust bedding. Journal of Dairy Science 8, 16001605.
Hogan, JS, Bogacz, VL, Thompson, LM, Romig, S, Schoenberger, PS, Weiss, WP and Smith, KL 1999. Bacterial counts associated with sawdust and recycled manure bedding treated with commercial conditioners. Journal of Dairy Science 82, 16901695.
Hogan, JS and Smith, KL 2012. Managing environmental mastitis. Veterinary Clinics North America Food Animal Practice 28, 217224.
Hogan, JS, Smith, KL, Hoblet, KH, Todhunter, TA, Schoenberger, PS, Hueston, WD, Pritchard, DE, Bowman, GL, Heider, LE, Brockett, BL and Conrad, HR. 1989. Bacterial counts in bedding materials used on nine commercial dairies. Journal of Dairy Science 72, 250258.
Hogan, JS, Smith, KL, Todhunter, DA and Schoenberger, PS 1990. Bacterial counts associated with recycled newspaper bedding. Journal of Dairy Science 73, 17561761.
Homerosky, E and Hogan, JS. 2015. Effects of freezing on bacterial counts in bovine bedding materials. In: Proceedings of the 54th National Mastitis Council Meeting, 1–3 February 2015, Memphis, Tennessee, USA. National Mastitis Council Inc., Verona, WI, pp. 162.
Husfeldt, AW, Endres, MI, Salfer, JA and Janni, KA 2012. Management and characteristics of recycled manure solids used for bedding in Midwest freestall dairy farms. Journal of Dairy Science 95, 21952203.
Kristula, MA, Rogers, W, Hogan, JS and Sabo, M 2005. Comparison of bacteria populations in clean and recycled sand used for bedding in dairy facilities. Journal of Dairy Science 88, 43174325.
King, MT, Pajor, EA, LeBlanc, SJ and DeVries, TJ 2016. Associations of herd-level housing, management, and lameness prevalence with productivity and cow behavior in herds with automated milking systems. Journal of Dairy Science 99, 90699079.
Levison, LJ, Miller-Cushon, EK, Tucker, AL, Bergeron, R, Leslie, KE, Barkema, HW and DeVries, TJ 2016. Incidence rate of pathogen-specific clinical mastitis on conventional and organic Canadian dairy farms. Journal of Dairy Science 99, 13411350.
Manninen, E, de Passille, AM, Rushen, J, Norring, M and Saloniemi, H 2002. Preferences of dairy cows kept in unheated buildings for different kind of cubicle flooring. Applied Animal Behaviour Science 75, 281292.
Nash, CG, Kelton, DF, DeVries, TJ, Vasseur, E, Coe, J, Heyerhoff, JZ, Bouffard, V, Pellerin, D, Rushen, J, de Passillé, AM and Haley, DB 2016. Prevalence of and risk factors for hock and knee injuries on dairy cows in tiestall housing in Canada. Journal of Dairy Science 99, 64946506.
Nielsen, BH, Thomsen, PT and Sørensen, JT 2011. Identifying risk factors for poor hind limb cleanliness in Danish loose-housed dairy cows. Animal 10 16131619.
Popescu, S, Borda, C, Diugan, EA, Spinu, M, Groza, IS and Sandru, CD 2013. Dairy cows welfare quality in tie-stall housing system with or without access to exercise. Acta Veterinaria Scandinavica 55, 4353.
Rowbotham, RF and Ruegg, PL 2015. Association of bedding types with management practices and indicators of milk quality on larger Wisconsin dairy farms. Journal of Dairy Science 98, 78657885.
Rowbotham, RF and Ruegg, PL 2016a. Associations of selected bedding types with incidence rates of subclinical and clinical mastitis in primiparous Holstein dairy cows. Journal of Dairy Science 99, 47074717.
Rowbotham, RF and Ruegg, PL 2016b. Bacterial counts on teat and skin in new sand, recycled sand, and recycled manure solids used as bedding in freestalls. Journal of Dairy Science 99, 65946608.
SAS Institute. 2013. SAS version 9.4. SAS Institute Inc., Cary, NC, USA. Retrieved on 15 February 2015 from
Sawant, AA, Pillai, SR and Jayarao, BM 2002. Evaluation of five selective media for isolation of catalase-negative gram-positive cocci from bulk tank milk. Journal of Dairy Science 85, 11271132.
Schreiner, DA and Ruegg, PL 2003. Relationship between udder and leg hygiene scores and subclinical mastitis. Journal of Dairy Science 86, 34603465.
Schüller, LK, Burfeind, O and Heuwieser, W 2013. Short communication: comparison of ambient temperature, relative humidity, and temperature-humidity index between on-farm measurements and official meteorological data. Journal of Dairy Science 96, 77317738.
Tucker, CB and Weary, DM 2004. Bedding on geotextile mattresses: how much is needed to improve cow comfort? Journal of Dairy Science 87, 28892895.
Tucker, CB, Weary, DM and Fraser, D 2004. Free-stall dimensions: Effects on preference and stall usage. Journal of Dairy Science 87, 12081216.
van Gastelen, S, Westerlaan, B, Houwers, DJ and van Eerdenburg, FJACM. 2011. A study on cow comfort and risk for lameness and mastitis in relation to different types of bedding materials. Journal of Dairy Science 94, 48784888.
Vasseur, E, Rushen, J, Haley, DB and de Passillé, AM 2012. Sampling cows to assess lying time for on-farm animal welfare assessment. Journal of Dairy Science 95, 49684977.
von Keyserlingk, MAG, Barrientos, A, Ito, K, Galo, E and Weary, DM 2012. Benchmarking cow comfort on North American freestall dairies: lameness, leg injuries, lying time, facility design, and management for high-producing Holstein dairy cows. Journal of Dairy Science 95, 73997408.
Watters, MA, Meijer, KM, Barkema, HW, Leslie, KE, von Keyserlingk, MA and DeVries, TJ 2013. Associations of herd-and cow-level factors, cow lying behavior, and risk of elevated somatic cell count in free-stall housed lactating dairy cows. Preventive Veterinary Medicine 111, 245255.
Wolfe, T, Vasseur, E, DeVries, TJ and Bergeron, R 2018. Effects of alternative deep bedding options on dairy cow preference, lying behavior, cleanliness, and teat end contamination. Journal of Dairy Science 101, 530536.
Zaffino Heyerhoff, JC, LeBlanc, SJ, DeVries, TJ, Nash, CG, Gibbons, J, Orsel, K, Barkema, HW, Solano, L, Rushen, J, de Passillé, AM and Haley, DB 2014. Prevalence of and factors associated with hock, knee, and neck injuries on dairy cows in freestall housing in Canada. Journal of Dairy Science 97, 173184.
Zdanowicz, M, Shelford, JA, Tucker, CB, Weary, DM and von Keyserlingk, MAG 2004. Bacterial populations on teat ends of dairy cows housed in free stalls and bedded with either or sawdust. Journal of Dairy Science 87, 16941701.
Zehner, MM, Farnsworth, RJ, Appleman, RD, Larntz, K and Springer, JA 1986. Growth of environmental mastitis pathogens in various bedding materials. Journal of Dairy Science 69, 19321941.


Type Description Title
Supplementary materials

Robles et al. supplementary material
Robles et al. supplementary material

 Word (97 KB)
97 KB

Bacterial concentrations in bedding and their association with dairy cow hygiene and milk quality

  • I. Robles (a1), D. F. Kelton (a2), H. W. Barkema (a3), G. P. Keefe (a4), J. P. Roy (a5), M. A. G. von Keyserlingk (a6) and T. J. DeVries (a1)...


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed