Abstract #410
Section: Ruminant Nutrition (orals)
Session: Ruminant Nutrition 4: Production and Efficiency
Format: Oral
Day/Time: Tuesday 2:30 PM–2:45 PM
Location: Junior Ballroom A
Session: Ruminant Nutrition 4: Production and Efficiency
Format: Oral
Day/Time: Tuesday 2:30 PM–2:45 PM
Location: Junior Ballroom A
# 410
Effect of adding molasses-based liquid feed to a high-straw dry cow diet on intake and behavior of Holstein dairy cows.
C. Havekes*1, T. F. Duffield2, A. J. Carpenter1, T. J. DeVries1, 1Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada, 2Department of Population Medicine, University of Guelph, Guelph, ON, Canada.
Key Words: dry cow diet, molasses, sorting behavior
Effect of adding molasses-based liquid feed to a high-straw dry cow diet on intake and behavior of Holstein dairy cows.
C. Havekes*1, T. F. Duffield2, A. J. Carpenter1, T. J. DeVries1, 1Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada, 2Department of Population Medicine, University of Guelph, Guelph, ON, Canada.
The objective of this study was to determine the effect of adding molasses-based liquid feed to a high-straw dry cow diet on intake and behavior of dairy cows. Multiparous Holstein cows (n = 40) were enrolled at dry off (~45 d before expected calving) and assigned to 1 of 2 treatments, a high-straw (35% wheat straw on DM basis) dry cow diet with: 1) no molasses (CON; n = 20; 11.6% CP, 1.35 Mcal/kg NEL) or 2) supplemented with 1 kg/cow/d (DM) of molasses (LF; n = 20; 11.7% CP, 1.38 Mcal/kg NEL). At calving all cows were fed the same lactating TMR (14.0% CP, 1.64 Mcal/kg NEL) and followed for 28 d. DMI, feeding behavior, and rumination activity were recorded automatically. TMR and ort samples were collected 2x/wk to determine differences in sorting. A particle separator was used to separate feed samples into 4 fractions: long (>19mm), medium (<19mm, > 8mm), short (<8mm, > 4mm), and fine (<4mm) particles. Feed sorting was calculated as: actual intake of each particle fraction expressed as a % of predicted intake. Data were analyzed in mixed-effect linear models, treating day as a repeated measure. LF cows had greater DMI (15.1 ± 0.26 vs 13.8 ± 0.26 kg/d; P = 0.001) and tended to spend less time ruminating (513.9 ± 8.55 vs 534.6 ± 8.54 min/d; P = 0.1). LF cows tended to have shorter meals (48.3 ± 4.64 vs. 60.4 ± 4.78 min/meal; P = 0.08), a shorter interval between meals (195.2 ± 8.72 vs 217.4 ± 9.0 min; P = 0.09) and more frequent meals (6.2 ± 0.79 vs 5.5 ± 0.24; P = 0.07), while consuming their feed faster (0.10 ± 0.001 vs 0.08 ± 0.001 kg DM/min; P = 0.04) compared with CON cows. Regardless of treatment, cows sorted against the longest ration particles, with CON cows sorting more against these (81.9 ± 2.5 vs 94.5 ± 2.5%; P = 0.001). CON cows did not sort for or against short particles (100.4 ± 0.56%), but LF cows tended to sort against these (98.8 ± 0.56%; P = 0.06). Post-calving, LF cows did not sort for long particles (100.3 ± 1.3%), but CON cows continued to sort against these (95.3 ± 1.3%; P = 0.01). The results suggest that supplementing a molasses-based liquid feed in high-straw dry cow diets may improve intake and consistency in nutrients consumed during the dry period and in early lactation.
Key Words: dry cow diet, molasses, sorting behavior
