Time budgets for 14 cows housed in a 3-row free-stall pen were obtained for 4 filming sessions timed to capture different climatic conditions, with a range in mean pen temperature-humidity index from 56.2 to 73.8. Mean lying time decreased from 10.9 to 7.9 h/d from the coolest to the hottest session filmed. This change in behavior occurred predominantly between 0600 h and 1800 h. Time spent standing in the alley increased from 2.6 to 4.5 h/d from the coolest to the hottest session filmed, with changes occurring between 1200 h and 1800 h. There was a negative effect of increasing locomotion score over the summer with higher locomotion scores associated with less time spent standing up in the alley. Time spent drinking increased from 0.3 to 0.5 h/d across the range in temperature-humidity index. Filming session alone did not affect time spent standing in the stall, but the effect of locomotion score was significant, with score 2 and score 3 cows standing in the stall longer than score 1 cows (4.0 and 4.4 compared with 2.9 h/d respectively). Behavioral changes observed and traditionally associated with heat stress were confounded by changes in locomotion score. Increases in claw horn lesion development reported in the late summer may be associated with an increase in total standing time per day. The changes in behavior described were because of mild to moderate heat stress. The finding that activity shifts occur around a temperature-humidity index of 68 supports the use of more aggressive heat-abatement strategies implemented at an activation temperature of around 21 degrees C.

Total mixed ration (TMR) samples (n = 110) were analyzed for dry matter (DM), crude protein (CP), soluble CP, neutral detergent fiber (NDF), NDF CP, starch, ash, fat, total ethanol-soluble carbohydrate, and nonfiber carbohydrate (NFC). Rapidly and slowly degraded and undegraded in situ CP fractions and in vitro DM, organic matter, and NDF digestibility were determined on each TMR. The TMR were scanned using near-infrared reflectance spectroscopy (NIRS); spectra were retained with NIRS calibration and cross-validation statistics were determined using partial least squares regression methods. The CP, NDF, starch, in vitro DM, and in vitro indigestible NDF contents of TMR were predicted by NIRS with good degrees (R2 >0.85) of accuracy with proportionally low standard errors of prediction. Moderate utility of NIRS to predict the NFC (R2 = 0.83) and fat content (R2 = 0.81) of TMR was observed. Rapidly, slowly, and undegraded in situ CP fractions in TMR were not well predicted by NIRS. Similarly, soluble CP, NDF CP, total ethanol-soluble carbohydrate, and in vitro NDF digestibility (% of NDF) were not well predicted by NIRS. Ratios of nutrient range to reference laboratory method error were calculated and found to be positively related (R2 = 0.84) to NIRS predictability of a given TMR nutrient, suggesting some laboratory procedures were not precise enough to yield suitable NIRS predictions. Data suggest that NIRS has utility to predict basic nutrients such as CP, NDF, starch, NFC, and fat in TMR. However, difficulty was observed using NIRS in predicting key biological nutrients in TMR such as in situ CP fractions and in vitro NDF digestibility. Difficulty of NIRS in predicting these nutrients is related to the level of reference method error in relationship to the range of nutrient values in TMR, but other sources of prediction error may exist.

The behavior of 59 cows in 4 herds, each with Comfort Zone-design free stalls with dimensions suitable for 700-kg, mature Holstein dairy cows, was filmed for a 48-h period. Comparison was made between nonlame, slightly lame, and moderately lame cows on either rubber-crumb-filled mattress stall surfaces bedded with a small amount of sawdust (2 herds) or a Pack Mat design, which consisted of a rubber-crumb-filled mattress pad installed 5 cm below a raised rear curb, bedded with 5 to 8 cm of sand bedding (2 herds). All other stall design components were similar. Despite adequate resting space and freedom to perform normal rising and lying movements, lame cows on mattresses stood in the stall for >2 h longer than nonlame cows. Although a significant increase in stall standing behavior was observed in lame cows on Pack Mat stalls, the mean (95% confidence interval) standing time in the stall was only 0.7 (0 to 3.0) h/d for nonlame cows and 1.6 (0 to 4.2) h/d for moderately lame cows, which was less than the 2.1 (0 to 4.4), 4.3 (1.6 to 6.9), and 4.9 (2.5 to 7.3) h/d spent standing in the stall for nonlame, slightly lame, and moderately lame cows on mattresses, respectively. This observation supports the hypothesis that it is the nature of the stall surface that dictates changes in stall standing behavior observed in lame cows, rather than other components of stall design. The finding that only 5 to 8 cm of sand over a mattress pad provides most of the benefits of deep sand-bedded stalls, along with other advantages related to stall maintenance and manure handling, gives farmers another useful housing alternative with which to improve cow comfort and well-being.

The goal of this observational study was to determine whether there were significant differences in feed bunk utilization patterns of dairy cows in free-stall pens with either 2 or 3 rows of stalls. Previously recorded 24-h videos of the high-yielding, mature cow group in 5 herds with 2-row pen designs and 5 herds with 3-row pen designs that were provided fresh TMR once a day after the morning milking were scan-sampled at 10-min intervals to record feed bunk utilization score (proportion of feed bunk spaces in the pen that were filled). Data were aligned according to peak feed bunk utilization score following fresh feed delivery (primary peaks), return from the afternoon milking (secondary peaks), and return from the night milking (tertiary peaks). Bunk utilization score was highest for primary peaks; scores were not significantly different between 2- and 3-row pens (0.65 vs. 0.71 +/- 0.1, respectively), and rates of decline in bunk utilization score were similar over the ensuing 90-min period between pen designs. Differences in bunk utilization between peak type and pen row type were observed; tertiary bunk utilization with 2-row pens was significantly lower than bunk utilization with 3-row pens and significantly lower than either primary or secondary bunk utilization in 2-row pens. The feed space allowance provided by a 2-row pen design potentially allows cows to demonstrate other important feeding behaviors, such as avoidance of conflicts and maintenance of greater inter-cow distances between neighbors while feeding.

Time budgets for 14 cows housed in a three-row free stall pen were obtained for four filming sessions timed to capture different climatic conditions, with a range in mean pen temperature humidity index from 56.2 to 73.8. Mean lying time decreased from 10.9 h/d to 7.9 h/d from the coolest to the hottest session filmed. Time spent standing in the alley increased from 2.6 h/d to 4.5 h/d from the coolest to the hottest session filmed. There was a negative effect of increasing locomotion score over the summer with higher locomotion scores associated with less time spent standing in the alley. Time spent drinking increased from 0.3 to 0.5 h/d across the range in temperature humidity index. Filming session alone did not affect time spent standing in the stall, but the effect of locomotion score was significant, with score 2 and 3 cows standing in the stall longer than score 1 cows (4.0 and 4.4 compared with 2.9 h/d respectively).