Sensitivity and specificity of a tail-activity measuring device for calving prediction in dairy cattle.

Efficient calving surveillance is essential for avoiding stillbirth due to unattended dystocia. Calving sensors can help detect the onset of parturition and thus ensure timely calving assistance if necessary. Tail-raising is an indicator of imminent calving. The objective of this study was to evaluate a tail-mounted inclinometer sensor (Moocall Ltd., Dublin, Ireland) and to monitor skin integrity after sensor attachment. Cows (n = 157) and heifers (n = 23) were enrolled at 275 d post insemination, and a sensor was attached to each cow's tail. Investigators checked for signs indicating the onset of stage II of parturition, verified the position of the sensor, and evaluated the skin integrity of the tail above and below the sensor hourly for 24 h/d. We used 5 different intervals (i.e., 1, 2, 4, 12, and 24 h until calving) to calculate sensitivity and specificity. Sensors continuously remained on the tail (i.e., within 3 cm of the initial attachment position) after initial attachment until the onset of calving in only 13.9% of animals (n = 25). Sensors were reattached until a calving event occurred (51.6%) or the animal was excluded for other reasons (34.4%). In 31 animals the sensor was removed because the tail was swollen or painful. Heifers were significantly less likely than cows to lose a sensor but more likely to experience tail swelling or pain. Depending on the interval preceding the onset of parturition, sensitivity varied from 19 to 75% and specificity from 63 to 96%.

Albumin priming does not prolong hemofilter life.

The hypothesis was tested that prepriming a hemofilter and lines with heparinized human albumin (NSA) instead of heparinized saline (NS) increases filter survival time. In a university affiliated intensive care unit, all patients were eligible who required continuous venovenous hemodiafiltration and who did not have pre-existing coagulopathy or contraindications to heparin. New hemofilters were randomized to priming with 2 liters NS or 1 liter NS followed by 500ml NSA. The prime was recirculated for at least 30 minutes before connection to the patient. Anticoagulation was tightly controlled, aiming for a patient activated partial thromboplastin time (APTT) of 60 seconds. Survival analysis was used to compare filter life. Elective discontinuation (e.g., for surgery) were treated as censored data. A total of 91 hemofilters were used in 40 patients during 9 months: 45 randomized to NS, and 46 to NSA. Of these, 57 hemofilters were used until spontaneous failure, 28 NS and 29 NSA; 34 hemofilters were electively discontinued, 17 in each group. Anticoagulation was identical in both groups; the mean APTT value (+/- SE) was 58.2 seconds (+/- 3.1) for NS and 58.0 seconds (+/- 2.8) for NSA (p > 0.9 unpaired t-test). Platelet counts were very similar at 170 x 10(9) (+/- 21.8) for NS and 181 x 10(9) (+/- 23.7) for NSA (p = 0.74 unpaired t-test). There was no significant difference in the filter life between the two groups. For NS, median filter life was 37.8 hours (range 0.6-120); for NSA, median filter life was 45.4 hours (range 2.5-109; p = 0.998 log rank). The power to detect a 50% improvement in filter life was > 90%. Based on this data, the use of albumin priming as an aid to increased hemofilter life can not be recommended.