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131.
The pre‐medicant chosen may influence the ease with which gastroduodenoscopy (GD) is performed. The purpose of this study was to evaluate the relative ease of GD in cats under ketamine and isoflurane anesthesia after IM injection of hydromorphone (H, 0.1 mg kg?1), hydromorphone plus glycopyrrolate (HG, 0.1 mg kg?1 (H), 0.01 mg kg?1 (G)), medetomidine (M, 0.03 mg kg?1), or butorphanol (B, 0.4 mg kg?1). Eight cats were assigned randomly to receive each treatment in a cross‐over design with at least 7 days between treatments. Twenty minutes after pre‐medication, medetomidine produced greater (p = 0.001) sedation than the other treatments when assessed, using a subjective ordinal scale. The cats were injected with ketamine (10 mg kg?1 IM), orotracheally intubated, connected to a pediatric circle breathing system, and allowed to spontaneously breathe isoflurane in oxygen. Once end‐tidal isoflurane concentration was stable at 1.4% for 15 minutes, endoscopy was started. A single endoscopist (REG), who was unaware of the treatment used, performed all endoscopies. The endoscopist scored the difficulty of endoscopy subjectively (0–3). The significance of differences between treatments was evaluated using Friedman's test. Time for entering the stomach was 9.4 (4.7–15.9) (median (minimum–maximum)), 6.6 (5.2–11.7), 8.4 (6.3–16.5), and 7.7 (5.1–14.7) seconds and for entering the duodenum from the stomach was 20.5 (13.8–40.9), 18.2 (10.3–39.8), 20.2 (16.2–119.5), and 22.2 (11.8–83.8) seconds for H, HG, M, and B treatments, respectively. There were no significant differences in the time for, or difficulty of, endoscopy. We conclude that any of these drugs can be used satisfactorily at the doses and combinations tested to pre‐medicate cats prior to general anesthesia for GD.  相似文献   
132.
The aim of this study was to investigate the effects of different concentrations of oral supplementation with selenium (Se) upon ram sperm parameters. Thirty rams managed in stall under intensive system were used and divided into five groups (six animals per group) as follows: control group (G1) mineral mixture supplementation without Se, group 2 (G2) mineral mixture supplemented with 5 mg/kg Se, group 3 (G3) supplemented with 10 mg/kg Se, group 4 (G4) supplemented with 15 mg/kg Se and group 5 (G5) supplemented with 20 mg/kg Se. For each group, there was an adjustment period of 14 days. The experimental period was 350 days. Every 56 days, the animals were weighed and semen samples were collected by electroejaculation. Semen analysis included volume, mass moviment, total motility, vigour, concentration and morphology. For plasmatic and acrosomal membrane integrity evaluation and mitochondrial membrane potential were used a combination of fluorescent probes. Differences between means values obtained by analysis of variance were verified by Tukey test with 5% probability. There was no statistical difference between treatment groups in relation to volume, mass moviment, total motility, vigour, concentration, plasma and acrosomal membrane integrity (p > .05). Sperm morphology was different between treatment groups, the G1 (0 mg of selenium) had the highest percentage of major defects (11.11 ± 1.11a; p < .05). It was concluded that selenium decrease the percentage of sperm defects and did not directly influence on ram sperm volume, mass moviment, total motility, vigour, concentration and membrane integrity.  相似文献   
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