Glucose tolerance of pregnant sows is related to postnatal pig mortality

An experiment was conducted on three farms to study the relationship between the results of an oral glucose tolerance test on d 104 +/- 4 of pregnancy and subsequent reproductive performance of 104 multiparous sows. After an overnight period without feed, sows were fed (3 g/kg BW.75) glucose, and blood samples were taken for analyses of glucose at -10, 10, 20, 30, 40, 50, 60 70, 80, 90, 105, and 120 min after administration of glucose. Glucose concentrations before glucose administration ranged from 2.0 to 3.6 mmol/L. Sows with lesser pretest glucose concentrations had longer (P < .01) durations of pregnancy (corrected for number of live pigs born) and heavier (P < .05) pigs at birth (corrected for farm and number of live pigs born). Peak glucose concentrations and areas under the curves (i.e., first 70 min and entire 120 min) ranged from .1 to 4.4 mmol/L, -40 to 211 (mmol/L).min, and -95 to 247 (mmol/L).min, respectively. Sows with greater (P < .01) peak concentration of glucose and greater area under the curve (first 70 min [P < .01] and entire 120 min [P < .01]) had increased pig mortality during the first 7 d after farrowing (corrected for live weight of the sows). In 83 sows, a sample of morning urine (before feeding) was collected and tested for glucose and ketone bodies. Neither glucose nor the ketone body acetoacetic acid was detected in the urine. The results indicate that sows that are less glucose-tolerant have greater pig mortality.