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Time spent lying by lactating Holstein-Friesian cows of varying body condition scores (BCS) and milk yield was measured using an animal activity monitor. A 3-week average BCS was calculated for each cow; and in total, 84 cows were selected with 28 cows each among three BCS categories (Thin: BCS<2.75; Moderate: 2.75 > or = BCS<3.25; Heavy: BCS> or = 3.25) and two stage of lactation categories (<150 days in milk or >150 days in milk). Cows were kept in two management systems: parlour/freestall (n=60) or automated milking system/freestall (n=24). Behaviour was recorded for 5.3+/-0.1 d for each cow. Production levels were considered using a 28-d rolling average of daily milk production. Cows that exhibited clinical lameness before or during the observation period were excluded from analyses. For cows exhibiting oestrus, the day prior to, day of, and day following breeding were removed. The final analysis included 77 cows (408 d of observation). A mixed model was fitted to describe average daily hours spent lying. Results demonstrated that lying time increased as days in milk (DIM) increased (P=0.05). Variables that were tested but not significant (P>0.05) were BCS category, parity category (1 or 2) and 28-d rolling average daily milk production. Although a numerical trend for increasing hours spent lying with increasing BCS was observed, after accounting for other factors in the mixed model, BCS did not significantly impact lying time. Continued investigation of these management factors that impact lying time and bouts, using new technologies, more cows, and more herds will help dairy owners better manage facilities and cow movements to optimize this essential behaviour.

Transition of primiparous heifers to the milking herd is a period with multiple stressors. The objective of these studies was to determine effects of parlour experience and prepartum milking (pre-milking) on behavioural and physiological indicators of stress after calving. Two experiments were conducted, one was in a free-stall housing confinement system and the second was in a modified grazing system. Forty-eight first-calf heifers were assigned to three treatments: control; experienced heifers taken through the parlour without milking; or pre-milk heifers milked for 3 weeks prior to estimated parturition. Blood was collected within 24 h of parturition and on days 3, 5, 7, 10 and 14 following parturition for cortisol and acute phase protein determination. In the grazing system, 20 heifers were assigned to a prepartum milked or control group as in the confinement system and behaviour observations included days -21, -14, -7, -5, -3 and -1 relative to calving and days 1, 3, 7, 9, 14, and 16 post-calving. Milk production was greatest for prepartum milked heifers in both housing systems. However, somatic cell score was reduced by prepartum milking only in the confinement system. Balking occurred least in parlour-experienced heifers. In confinement housing, shifting while in the parlour was the only behaviour that was greater at first milking in control heifers. Kicking was most frequent for parlour experienced heifers on day 2. Grazing system pre-milked heifers shifted more at their first milking (day -21) than did the controls at their first milking (day 1). Shifting within cow was greatest on day -21 compared with day -5 (P<0.05). Pre-milked heifers shifted more on day 1 post-calving than did the control heifers (P<0.05). These results showed that shifting was the most indicative behaviour of restlessness, was transient, and decreased by day 5 prior to calving. Cortisol and alpha1-acid glycoprotein concentrations were not different; however, haptoglobin increased for all treatments up to and including day 3 and haptoglobin concentrations of pre-milked heifers began to decrease by day 5 post-calving. Pre-milked heifers had lower haptoglobin concentrations than the control heifers and tended to have lower concentrations than experienced heifers on day 10 post partum. By day 14 post partum, all haptoglobin concentrations were <200 microg/ml, but the haptoglobin concentration of control heifers was greater than that of pre-milked and experienced heifers. These results showed that prepartum milking and parlour experience shorten some acute phase protein responses, but minimally affect early parlour behaviours.