Lying behavior in dairy cattle can provide insight into how cows interact with their environment. Although lying behavior is a useful indicator of cow comfort, it can be time consuming to measure. In response to these time constraints, using data loggers to automate behavioral recording has become increasingly common. We tested the accuracy of the Onset Pendant G data logger (Onset Computer Corporation, Bourne, MA) for measuring lying behavior in dairy cattle (n=24 cows; 12 in each of 2 experiments). Cows wore the logger on the lateral (experiment 1) or medial (experiment 2) side of the hind leg above the metatarsophalangeal joint. Loggers recorded behavior at 4 sampling intervals (6, 30, 60, and 300 s) for at least 1.5 d. Data were smoothed using 3 editing methods to examine the effects of short, potentially erroneous readings. For this purpose, Microsoft Excel macros (Microsoft Corp., Redmond, WA) converted readings (i.e., lying events bordered by standing or vice versa) occurring singly or in consecutive runs of ≤2 or ≤6. Behavior was simultaneously recorded with digital video equipment. The logger accurately measured lying and standing. For example, predictability, sensitivity, and specificity were >99% using 30-s sampling and the single-event filter compared with continuously scored video recordings. The 6- and 30-s sampling intervals were comparable for all aspects of lying behavior when short events were filtered from the data set. Estimates of lying time generated from the 300-s interval unfiltered regimen were positively related (R(2) ≥ 0.99) to estimates of lying time from video, but this sampling regimen overestimated the number of lying bouts. This is likely because short standing and lying bouts were missed (12 and 34% of lying and standing bouts were <300 s in experiment 1 and 2, respectively). In summary, the data logger accurately measured all aspects of lying behavior when the sampling interval was ≤30 s and when short readings of lying and standing were filtered from the data set.

Dairy cattle spend less time lying and show signs of increased stress when housed in rainy and windy conditions, but no work has separated the effects of exposure to inclement weather from muddy conditions underfoot. Our objective was to evaluate the effects of muddy conditions alone on lying behavior, hygiene, and physiological responses. We housed pairs of pregnant, nonlactating dairy cattle (n = 12; 6 primigravid heifers, 6 multiparous cows) in enclosed pens with dirt floors and a concrete feed apron. Cattle were exposed to 3 levels of soil moisture: 90 (dry), 74 (muddy), or 67% (very muddy) dry matter for 5 d each in a replicated 3 × 3 Latin square design. Lying time was measured on all days with data loggers, and lying locations and postures were recorded on the final day of each treatment. Before and after each treatment, blood samples were collected, and the percentage of dirty surface area was measured on the udder, hind leg, and side of each animal. Cattle spent less time lying down in muddier conditions, especially in the first 24 h of exposure, when cows and heifers spent only 3.2 and 5.8 h, respectively, lying down in the muddiest treatment compared with 12.5 and 12.7 h on dry soil. When the soil was dry, cattle never chose to lie down on concrete, but in muddier conditions they spent a greater proportion of their lying time on concrete (mean ± SE: 56 ± 14 and 10 ± 8% in the very muddy and muddy treatments, respectively). The shift in lying location was more marked for heifers, and all 6 spent ≥87% of their lying time on concrete in the muddiest treatment. When cattle chose to lie down on wetter soil, they limited the surface area exposed to their surroundings by tucking their legs beneath their bodies (mean ± SE: 30 ± 11, 15 ± 4, and 5 ± 2% of lying observations in the very muddy, muddy, and dry treatments, respectively). Despite cattle spending less time on wetter soil, all 3 measured body parts became dirtier in muddier conditions (1.4-, 1.6-, and 1.8-fold more on the leg, udder, and side, respectively, in the muddiest compared with the driest treatment). In addition, higher soil moisture levels resulted in greater reductions in white blood cell counts relative to baseline levels (-0.95, -0.43, and 0.34 × 10/L relative to baseline levels in the very muddy, muddy, and dry treatments). Muddy conditions, even in the absence of wind or rain, are aversive for cattle and have negative implications for their welfare.

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The removal of corn oil from dried distillers grains using solvent extraction allows a higher level of inclusion for solvent-extracted dried distillers grains with solubles (SDG) in rations and reduces the risk of milk fat depression in lactating Holstein dairy cows. The objective of this study was to evaluate the impact of substituting 70% of the canola meal (CM) with SDG on milk production and total mixed ration costs. A total of 1408 Holstein cows averaging 91 ± 49 days in milk were randomly enrolled to one of four dietary treatment groups: (1) primiparous control cows (PC) fed 13% CM and 0.21% urea; (2) primiparous SDG cows (PSDG) fed 4.2% CM, 8.8% SDG and 0.42% urea; (3) multiparous control cows (MC) with 13% CM and 0.21% urea; and (4) multiparous SDG cows (MSDG) with 4.1% CM, 8.6% SDG and 0.42% urea. The total mixed rations were formulated to be isonitrogenous. For the income over the feed costs from a control herd, the fed PC and MC’s total mixed rations and the fed PSDG and MSDG’s total mixed rations were compared. The milk yield, energy-corrected milk, milk fat yield, milk protein yield and milk protein % were lower in the PC cows compared to the PSDG cows. The MSDG cows scored lower in terms of the milk yield, milk protein yield and milk protein % and higher for the 3.5%-fat-corrected milk, milk fat yield and milk fat % compared to the MC cows. The total income, cost of dry matter and income over feed costs per cow/d were higher in the control vs. SDG simulated dairy herds. The control herd had a higher income over feed costs than the SDG herd because the average milk yield per cow/d was higher even though the SDG herd had a lower total mixed ration cost and higher milk fat production.