Abstract #T132

# T132
Variation of nutrient content and bacteria count of pasteurized waste milk fed to dairy calves.
W. S. B. Yoho*1, C. M. Hansen1, E. L. Stephas1, M. M. R. Rao1, T. J. Earleywine2, L. J. Van Roekel2, M. J. Radmer2, B. L. Miller1, 1Land O’Lakes, Inc, Gray Summit, MO, 2Land O’Lakes, Inc, Shoreview, MN.

From October 2006 to January 2017, pre- and post-pasteurized waste milk samples from 618 dairy farms across the United States were collected and analyzed to better understand how the nutrient content and bacteria count of milk varies within and across dairy farms. Both batch and high temperature short time (HTST) pasteurizers were used, as well as UV (UV) treatment of milk. Milk samples at each farm were collected for 7 consecutive days to determine total solids (TS), protein, butterfat, somatic cell count, and antibiotic presence, as well as bacteria count. On d 1 through 6, a post-pasteurized milk sample was collected at morning or evening calf feeding. On d 7, 3 samples for bacteria count were taken at the morning calf feeding: pre-pasteurized, immediately post-pasteurized, and post-pasteurized before feeding the last calf. Samples were stored between 1.67°C and 5.56°C, and then sent to Eurofins DQCI (Mounds View, MN) for all analyses. Data were analyzed by PROC FREQ and PROC MEANS of SAS; PROC UNIVARIATE of SAS was used for within and across farm variation. Mean TS, protein, and fat of post-pasteurized waste milk across all farms were 12.8%, 3.41%, and 3.92%, respectively. Minimum TS, protein, and fat of post-pasteurized waste milk were 7.67%, 2.13%, and 1.55%, respectively. Maximum TS, protein, and fat of post-pasteurized waste milk were 18.1%, 4.96%, and 9.47%, respectively. The coefficient of variation for TS, protein, and fat were 6.58%, 7.90%, and 17.32% within a farm, respectively; and 8.54%, 11.8%, and 19.2% across farms, respectively. Bacteria counts post-pasteurization were categorized as failed (>100,000 cfu), poor (20,001 – 100,000 cfu), or good (≤20,000 cfu). The percentage of farms in each category were as follows: failed- 27.44%, poor- 14.14%, good- 58.42%. In terms of last calf fed, 36.11% of farms failed, 18.23% were poor, and 45.66% were good. Antibiotics were detected in 56.8% of samples collected. Pasteurized waste milk is a highly variable source of nutrition for dairy calves and on-farm pasteurization does not consistently deliver waste milk with a low bacteria count.

Key Words: calf, pasteurized waste milk, pasteurizer