Abstract #M428

# M428
Urine pH, serum calcium, and dry matter intake evaluated in Jersey cows fed anionic salts or Animate.
Tyler J. Schell*1, Shelby A. Armstrong1, Derek J. McLean1, Ken P. Zanzalari1, James D. Chapman1, Lane O. Ely2, 1Phibro Animal Health Corporation, Quincy, IL, 2University of Georgia, Athens, GA.

Negative DCAD diets have been proven beneficial for reducing incidence of periparturient diseases in dairy cows, however maintaining dry matter intakes (DMI) have been an issue with these strategies. Twelve non-pregnant, nonlactating Jersey cows (464 kg ± 19 kg BW) were used in a crossover design study to evaluate the effect of diets fully acidified (−15 mEq/100g DM) with either an anionic salt mix (SM) or Animate (AN) on urine pH, serum calcium and DMI when fed continuously for 21 or 24 d. Cows were randomly assigned to diet (6 h/diet) at the onset of the study. The first feeding period was 24 d (P1) and the second was 21 d (P2), with a 7-d wash-out non-anionic (NA) diet period between P1 and P2. In P1, P2 and NA urine pH and DMI were recorded daily. Urine samples were collected mid-stream, 4–6 h post-feeding and pH measured. Anionic diets were offered in grain mixes and adjusted daily to maintain a urine pH between 5.5 and 6.0. Blood samples were taken on d 0 (diet assignment), 7, 14, 21, 24 in P1 and 7, 14 and 21 in P2. Diets were balanced using NDS Professional, fed as TMRs 1x/d in Calan gates and orts recorded. To insure adaptation to diets, data recorded in the last 4 d in P1, P2 and NA were averaged and compared across periods using PROC GLM and significance tested to P < 0.05. Urine pH in P1 and P2 for cows fed the SM and AN were 5.8 ± 0.14 and 5.66 ± 0.14, respectively, and were different from the NA (6.52 ± 0.14, P = 0.001). Serum calcium (mg/dL) was similar for cows fed SM or AN in P1 (9.32 ± 0.19 vs. 9.37 ± 0.2) and P2 (9.33 ± 0.21 vs. 9.2 ± 0.24) and not different from the NA (9.18 ± 0.12). Prior to start of P1, cows averaged 8.95 ± 0.18 kg DM. During P1 and P2, cows fed AN had greater DMI (+0.79 kg/d) than when fed the SM diets (P = 0.027). Comparing the last 4 d of P1 and P2, cows fed the AN diets consumed more DM (+1.16 kg/d, +1.02 kg/d, respectively) than when fed the SM diets (P = 0.001) but DMI was not different from the NA period (8.94 ± 0.19kg). In conclusion, Animate was equally effective as anionic salts for reducing urine pH and maintaining serum calcium levels in Jersey cows; however, DMI were significantly improved.

Key Words: dry matter intake, Animate, Jersey cow