Separated Manure Solids for Freestall Bedding


Mastitis is one of the costliest diseases for the U.S. Dairy Industry, and management decisions that may affect mastitis risk are considered carefully. One such decision is the choice of a bedding substrate that helps keep cows clean and comfortable. Maintaining good udder hygene does reduce mastitis risk. Several bedding options are available, and each has advantages and disadvantages. Separated manure solids (SMS) have been used as a dairy cow bedding substrate for many years. Some farms have used SMS successfully, meaning the transition to manure solids bedding did not increase mastitis and/or reduce milk quality. Other herds experienced increased mastitis around the time they switched to manure solids, and attributed this to bedding. Much research has been done to help the industry understand best management practices for use of this organic bedding substrate, but consensus still lacks on if and how SMS should be used.

The specific objective of this project was to analyze the records of collaborating farms specific to their management of manure solids as a bedding material. The five farms that participated in this study represent a variety of SMS management systems in New York.

The study analyzed:
• Quantitative bacterial culture and dry matter assessment of fresh and used bedding
• Qualitative teat skin surface cultures taken prior to and immediately following pre-milking preparation
• Barn temperature and humidity
• Herd milk quality data
o Clinical mastitis risk
o Subclinical mastitis risk
o Mastitis related culling risk
o Other herd data potentially influencing milk quality data
• Udder hygiene scoring
• Teat end hyperkeratosis scoring

Chart 1: SMS Bedding Cultures – Median Total Bacteria Count (Total Coliforms, Strep spp, Staph spp.)

Table 1: SMS Bedding Moisture Content

Table 2: Teat Skin Culture Results

Table 3: Udder Hygiene & Teat End Scores

Table 4: Farm Milk Quality Data

Risk of mastitis to dairy cows is multifactorial, with udder hygiene representing a significant proportion of that risk. Regardless of methods used to generate SMS, all used bedding cultures taken from the cow stalls had similarly high bacteria counts. Milk quality parameters varied across the five farms. Mastitis risk reduction investments in other areas, like milk parlor maintenance, optimizing milking routines, and general herd health may be better than investing in ways to reduce bacterial counts in SMS.


SMS can be used successfully as a stall bedding source if it results in good cow comfort and causes no decline in cow health, including mastitis.

Schwarz and Bonhotal, Using Manure Solids for Dairy Barn Bedding, Cornell Waste Management Institute, 2008

Schwarz et al., Use of Dried Manure Solids as Dairy Bedding: Frequency of Bedding Changes, Cornell Waste Management Institute, 2010

Husfeldt et al., Investigation of Recycled Manure Solids as Freestall Bedding for Dairy Cows in the Midwest, University of Minnesota, 2011

Bedding Materials and Udder Health, NYSCHAP Mastitis Module Fact Sheet

R. F. Rowbothham and P.L. Ruegg, Bacterial counts on teat skin and in new sand, recycled sand, and recycled manure solids used as bedding in freestalls, J. Dairy Sci., 2016

Monsallier, et al., Variability of microbial teat skin flora in relation to farming practices and individual dairy cow
characteristics, Dairy Sci. & Technol, 92:265-278, 2013. Smith, et al, Comparison of the effects of heat stress on milk and component yields and somatic cell score in Holstein and Jersey cows, J. Dairy Sci., 96:3028-3033, 2013


VAS DairyComp 305.

Dairy One DHIA Records Services. D.A. Schreiner and P.L. Ruegg, Relationship between udder and leg hygiene scores and subclinical mastitis, J. Dairy Sci., 2003 Nov;86(11):3460-5.

Neijenhuis et al., Evaluation of Bovine Teat Condition in Commercial Dairy Herds: 4. Relationship Between TeatEnd Callosity or Hyperkeratosis and Mastitis, Proceedings of the 2nd International Symposium on Mastitis and Milk Quality, 2001

Virkler, Quality Milk Production Services, Cornell University, Monitoring Parlor Performance using DC305.

This work was supported by the USDA National Institute of Food and Agriculture, Hatch Project 1004320.

For More Information:
Robert A. Lynch, DVM
Herd Health & Management Specialist
Cornell University PRO-DAIRY Program
B30 Morrison Hall
Ithaca, NY 14853