Abstract #231

# 231
Effectiveness of treating subclinical ketosis in dairy cows.
Albert J. Brown*1, Maurice L. Eastridge1, Leon D. Weaver2, K. J. Chapman2, 1The Ohio State University, Columbus, OH, 2Bridgewater Dairy, Montpelier, OH, US.

Ketosis is a major metabolic disorder of dairy cattle in the United States. There are various viewpoints on whether it is cost effective to treat subclinical cases of ketosis (SCK) with propylene glycol (PPG) and dextrose in comparison to treating animals that become clinically ketotic. For this trial, there was a control group and 2 treatment groups. Control cows had <1.2 mM/L β-hydroxybutarate (BHBA) and did not receive treatment. Treatment 1 cows were deemed SCK, defined by a blood BHBA of 1.2 to 2.9 mM/L and received 250 mL 50% dextrose solution intravenously and 300 mL PPG orally for 3 d. Treatment 2 cows also were SCK (same criteria as Trt 1) but did not receive the PPG and dextrose. Cows with > 2.9 mM/L BHBA were not enrolled in the trial. To determine treatment, blood was drawn from the tail vein/artery at 4 d in milk (DIM) and tested for BHBA using a Precision Xtra Meter (Abbott Laboratories, Abbott Park, IL). NEFA and BCS (1 = thin, 5 = fat) were recorded −14 to −3 d prepartum. Data were analyzed using the PROC GLM procedure with repeated measures of SAS (2012), with significance at P < 0.05 and trends at P < 0.10. Prepartum NEFA were similar between Trt 1 and 2 but lower for control (316, 300, and 240 μEq/mL, respectively). BHBA at 4 DIM was similar for Trt 1 and 2 but lower for control (1.66, 1.69, and 0.70 mM/L, respectively), with a similar pattern at 11 DIM (1.34, 1.46, and 0.69 mM/L, respectively). BCS at 11 DIM was higher for Trt 1 cows (3.45) than control (3.33) and Trt 2 cows (3.31). Milk yield during the first 90 DIM was similar for control and Trt 1 cows (42.7 vs. 42.1 kg/d, respectively), but milk yield was lower for Trt 2 cows (41.2 kg/d) compared with control cows and tended (P = 0.06) to be lower than for Trt 1 cows. Cows with SCK postpartum were showing signs of altered energy metabolism prepartum. Treatment for SCK had minimal effect on BHBA, appeared to increase BCS, and tended to increase milk yield. Additional data on health events and cost of treatments will provide further evidence to the effectiveness of treatment of SCK.

Key Words: ketosis, subclinical ketosis, propylene glycol