Abstract #269

# 269
Effect of stocking density and a barrier in a group close-up pen on the odds that dairy cows develop metritis after calving.
K. Creutzinger*1, H. Dann2, L. Moraes1, P. Krawczel3, K. Proudfoot1, 1The Ohio State University, Columbus, OH, 2William H. Miner Agricultural Research Institute, Chazy, NY, 3University of Tennessee, Knoxville, TN.

A high number of dairy cows succumb to disease after calving, and the risk of disease may be affected by the social environment before calving. The objective of this study was to determine the effect of stocking density and the provision of a barrier in group close-up pens on the likelihood that cows developed metritis after calving. A total of 319 Holstein dairy cows (primiparous = 113, multiparous = 206) that were part of a larger experiment were included in the study. Pens were dynamic as cows moved in 21 ± 3 d before their expected calving date and removed immediately after calving. At enrollment, cows were assigned randomly to one of 4 treatments using a 2 × 2 factorial arrangement including 1) high vs. low stocking density (9.7 to 12.9 m2 vs. 19.4 to 25.8 m2 lying space /cow), and 2) presence of a barrier (yes vs. no). The barrier was created using 2 road Jersey barriers and plywood (3.6 × 0.6 × 1.5 m). Pens were created using gates separating 4 areas within a large sawdust bedded pack and were replicated 4 times at 4 different periods so that all treatments were in all positions in the larger pack. Vaginal discharge was scored on 3, 7, 10, 14 d after calving with a Metricheck to diagnose subclinical and clinical metritis. Data describing metritis (healthy, subclinical and clinical) were analyzed with a multinomial proportional odds mixed model. Random effects for period, pen and pen × period × treatment were included in the model. Fixed effects describing the factorial arrangement of treatments as well as parity, calving assistance, and retained placenta were included in the model. Calving assistance (OR = 3.9; P < 0.0001) and retained placenta (OR = 6.4; P < 0.0001) significantly increased the odds of metritis severity. Stocking density (OR = 1.6; P > 0.05) and the presence of barrier (OR = 1.3; P > 0.05) did not affect the odds of developing metritis. No significant interactions were detected. Results suggest that moderate increases in stocking density and provision of a physical barrier in a group bedded-pack for close-up cows did not affect the odds of developing metritis after calving.

Key Words: stocking density, transition