Stress can negatively impact the health and productivity of lactating dairy cattle. The primary objective of this study was to determine the degree of stress experienced by dairy cattle around calving, and whether primiparous cattle were more stressed than multiparous cattle in the periparturient period. One hundred and six Holstein-Friesian cattle (34 primiparous, 72 multiparous) were studied. Animals were moved indoors into separate calving pens approximately 3 days before the anticipated calving date. Heart rate, respiratory rate, and mean arterial pressure (MAP) were determined daily from 3 days prepartum to 3 days postpartum. The MAP was measured using indirect oscillometry by application of a cuff to the coccygeal artery, and pressures were corrected for the height difference above the scapulohumeral joint. Plasma samples were collected and concentrations of glucose ([gluc]) and cortisol ([cortisol]) determined. Mixed models ANOVA was used for statistical analysis and P < 0.05 was considered significant. Least squares mean daily heart rates were consistently 10 bpm higher in primiparous (97bpm) than multiparous cattle (87bpm, P < 0.0001). Least squares MAP was consistently higher in primiparous (97mmHg) than multiparous cattle (91mmHg, P=0.0004). Least squares mean daily respiratory rates were consistently 8 breaths/min higher in primiparous (52 breaths/min) than multiparous cattle (44 breaths/min, P < 0.0001) Primiparous cattle had higher plasma [gluc] than multiparous cattle on days -2, -1, and 0.5 to 3.0 relative to parturition. Plasma [cortisol] was higher (p=0.028) in primiparous (10.3ng/mL) than multiparous (7.7ng/mL) cattle the day before parturition. We conclude that primiparous cattle are more stressed around parturition than multiparous cows. |
