Effects of the endophyte Acremonium coenophialum in tall fescue on pregnant mares and foal viability were evaluated. Twenty-two mature pregnant mares were randomly chosen to graze either Kentucky-31 tall fescue that was free from A coenophialum (endophyte-free, EF) or tall fescue infected with A coenophialum (endophyte-present, EP) after the first 90 days of pregnancy through parturition. Concentrations of pyrrolizidine and ergopeptine alkaloids were significantly greater in EP grass, compared with EF pasture. Ten of 11 mares grazing EP pasture had obvious dystocia. Mean duration of gestation was significantly greater for the EP group, compared with the EF group. Foal survivability was severely reduced among mares grazing Ep fescue with only 1 foal surviving the natal period. Udder development and lactation were low in mares grazing EP grass. The absence of clinical problems in mares grazing EF grass implicated the endophyte as the causative agent of reproductive problems and perinatal foal mortality in pregnant mares grazing endophyte-infected fescue grass. Caution should be exercised in allowing pregnant mares to graze pastures infected with the endophyte A coenophialum.

The steady-state response characteristics of a pulse oximeter were evaluated on intestinal segments of seven clinically normal halothane-anesthetized horses. Arterial oxygen tension > 200 mm of Hg, end tidal carbon dioxide from 30 to 35 mm of Hg, and systemic mean arterial pressure > 70 mm of Hg were maintained throughout the recording periods. Values for percentage of pulse oximeter oxygen saturation, pulsatile blood flow, and percentage of signal strength were recorded from jejunum, ileum, cecum, left ventral colon, left dorsal colon, and descending colon. Probe placement on intestinal segments was recorded as over or not over visible subserosal or transmural vessels. There was no significant difference between median values on the basis of vessel codes for pulse oximeter oxygen saturations, pulsatile flow, and signal strength. Median values recorded for pulse oximeter oxygen saturation were 93% from jejunum and ileum and 95% from cecum, left ventral colon, left dorsal colon, and descending colon; median values for pulsatile flow were 576 from jejunum, 560 from ileum, 560 from cecum, 574 from left ventral colon, 578 from left dorsal colon, and 560 from descending colon; median values for signal strength were 50% from jejunum, 67.5% from ileum, 60% from cecum, 75% from left ventral colon, 50% from left dorsal colon, and 52.5% from descending colon. Median values obtained from each anatomic location were not significantly different for pulsatile flow or signal strength. Median pulse oximetry oxygen values recorded from jejunum and ileum were significantly lower than values obtained from other intestinal segments. When calculated arterial oxygen saturation was compared with oxygen saturation determined by the pulse oximeter, pulse oximeter oxygen saturation was consistently lower by 6.7% (jejunum and ileum) and 4.7% (cecum, left ventral colon, left dorsal colon, and descending colon). Equine and human absorption spectra were generated and compared for reduced hemoglobin and oxyhemoglobin at wavelengths of 600 nm (red) to 950 nm (infrared). Extinction coefficients calculated at wavelengths used by the pulse oximeter (660 nm and 940 nm) were nearly identical. The pulse oximeter is a self-calibrating instrument that displays oxygen saturation, heart rate, plethysmographic waveform, and signal strength indicator. Probe application was rapid and easy. Response time for the appearance of a plethysmographic waveform ranged from 5 to 25 seconds.

We developed a single-pedicle, axial pattern tubed skin flap that could be transferred to an in vitro perfusion apparatus. On the basis of results of prosections, angiography, contact radiography, and surviving-length studies, it was concluded that a single-pedicle, axial pattern skin flap measuring 4 cm X 12 cm incorporating the caudal superficial epigastric artery would survive to its entire length. Subsequently, a surgical (stage 1) procedure was developed for the routine preparation of single-pedicle, axial pattern tubed skin flaps. Healing after the stage-1 procedure was evaluated by visual inspection and fluorescein angiography. Stage-1 procedures were performed successfully 149 of 160 (93%) times. A second surgical (stage 2) procedure was developed for routine cannulation of the caudal superficial epigastric artery and harvest of the tubed skin flap. Stage-2 procedures were performed successfully 136 of 144 (94%) times.

Effects of the endophyte Acremonium coenophialum in tall fescue on pregnant mares and foal viability were evaluated. Twenty-two mature pregnant mares were randomly chosen to graze either Kentucky-31 tall fescue that was free from A coenophialum (endophyte-free, EF) or tall fescue infected with A coenophialum (endophyte-present, EP) after the first 90 days of pregnancy through parturition. Concentrations of pyrrolizidine and ergopeptine alkaloids were significantly greater in EP grass, compared with EF pasture. Ten of 11 mares grazing EP pasture had obvious dystocia. Mean duration of gestation was significantly greater for the EP group, compared with the EF group. Foal survivability was severely reduced among mares grazing Ep fescue with only 1 foal surviving the natal period. Udder development and lactation were low in mares grazing EP grass. The absence of clinical problems in mares grazing EF grass implicated the endophyte as the causative agent of reproductive problems and perinatal foal mortality in pregnant mares grazing endophyte-infected fescue grass. Caution should be exercised in allowing pregnant mares to graze pastures infected with the endophyte A coenophialum.