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Association among peripartum health parameters, cud chewing and activity
Objectives of the current experiment were to evaluate cud chewing and activity of cows with peripartum disorders. Holstein animals (nulliparous = 77, parous = 219) were fitted with cud chewing/activity monitors from -17 to 17 d relative to calving. Blood sampled weekly from 0 to 20 d relative to calving were used for determination of beta-hydroxybutyrate (BHB) concentration and incidence of ketosis (BHB > 1,400 mmol/L). Blood sampled on d 0, 1, and 2 relative to calving were used for determination of total Ca concentration and incidence of sub-clinical hypocalcemia (Ca < 8.5 mg/dl). Cows were examined for retained placenta (RP) and metritis by study personnel. Data regarding twin calving and stillbirth were recorded. Outcomes measured over time (e.g. rumination and activity) were analyzed by ANOVA for repeated measures using the MIXED procedure. Nulliparous animals spent less time cud chewing than parous animals (P<0.01). There was a tendency for RP to be associated with cud chewing (P=0.08) because from -4 to 10 d relative to calving animals with RP had reduced cud chewing time (P<0.01). Even though there was no association between sub-clinical hypocalcemia and cud chewing time (P=0.19), the interaction between sub-clinical hypocalcemia and days relative to calving was associated with cud chewing time (P<0.01) because on days -16, -13, -11, and 0 relative to calving animals with sub-clinical hypocalcemia had reduced cud chewing time. Concentration of Ca was correlated with cud chewing time (r=0.15;P=0.02). Similarly, ketosis was not associated with cud chewing time (P=0.77) but the interaction between ketosis and days relative to calving was associated with cud chewing time (P<0.01). From 6 to 17 d relative to calving animals with ketosis had reduced cud chewing time. Concentration of BHB was correlated with cud chewing time (r=0.16;P<0.01). Nulliparous animals had (P<0.01) greater activity than parous cows. There was a tendency (P=0.10) for animals with stillbirth to have greater activity. There was (P<0.01) an association between RP and activity because from 0 to 11 d relative to calving activity of RP animals was reduced. Although ketosis was not (P=0.91) associated with activity, on d 0 and 1 relative to calving ketotic cows had greater activity and on d 10, 15, 16, and 17 relative to calving ketotic cows had reduced activity. Peripartum disorders are associated with altered cud chewing time and activity in the peripartum period.
Keywords: transition cow, cud chewing, activity