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181.
AIMS: To determine the pharmacokinetics, and anaesthetic and sedative effects of alfaxalone after I/V and I/M administration to cats.

METHODS: Six European shorthair cats, three males and three females, with a mean weight of 4.21 (SD 0.53) kg and aged 3.8 (SD 0.9) years were enrolled in this crossover, two–treatment, two-period study. Alfaxalone at a dose of 5?mg/kg was administered either I/V or I/M. Blood samples were collected between 2–480 minutes after drug administration and analysed for concentrations of alfaxalone by HPLC. The plasma concentration-time curves were analysed by non-compartmental analysis. Sedation scores were evaluated between 5–120 minutes after drug administration using a numerical rating scale (from 0–18). Intervals from drug administration to sit, sternal and lateral recumbency during the induction phase, and to head-lift, sternal recumbency and standing position during recovery were recorded.

RESULTS: The mean half-life and mean residence time of alfaxalone were longer after I/M (1.28 (SD 0.21) and 2.09 (SD 0.36) hours, respectively) than after I/V (0.49 (SD 0.07) and 0.66 (SD 0.16) hours, respectively) administration (p<0.05). Bioavailability after I/M injection of alfaxalone was 94.7 (SD 19.8)%. The mean intervals to sternal and lateral recumbency were longer in the I/M (3.73 (SD 1.99) and 6.12 (SD 0.90) minutes, respectively) compared to I/V (0 minutes for all animals) treated cats (p<0.01). Sedation scores indicative of general anaesthesia (scores >15) were recorded from 5–15 minutes after I/V administration and deep sedation (scores 11–15) at 20 and 30 minutes. Deep sedation was observed from 10–45 minutes after I/M administration. One cat from each group showed hyperkinesia during recovery, and the remainder had an uneventful recovery.

CONCLUSIONS AND CLINICAL RELEVANCE: Alfaxalone administered I/V in cats provides rapid and smooth induction of anaesthesia. After I/M administration, a longer exposure to the drug and an extended half life were obtained compared to I/V administration. Therefore I/M administration of alfaxalone could be a reliable, suitable and easy route in cats, taking into account that alfaxalone has a slower onset of sedation than when given I/V and achieves deep sedation rather than general anaesthesia.  相似文献   
182.
We evaluated the prevalence of mycobacterial infections (i.e., Mycobacterium bovis and non-tuberculous mycobacteria [NTM]) and their associated risk factors among cattle herds and trade cattle in southwestern Nigeria. Through cross-sectional study design, cattle herds from three locations were screened using the single intradermal comparative cervical tuberculin test based on two diagnostic standards; more than 4 mm (? 4 mm) and more than 2 mm (? 2 mm) cut-off points. Abattoir study involved screening trade cattle for tuberculous lesions. Overall, 515 cattle from 45 herds were screened. Using >?4 mm, animal level and herd prevalence of 11.7 and 46.7% were recorded, respectively. Applying the ? 2 mm cut-off, animal level and herd prevalence increased to 31.1 and 60.0%, respectively. Significantly, using the ? 2 mm cut-off, cattle in medium size herds/extensive management system (OR?=?1.6; 95% CI 1.1–2.5) and Sokoto Gudali (OR?=?2.3; 95% CI 1.4–3.8) were more at risk of being positive reactors, while Rahaji (OR?=?0.3; 95% CI 0.1–0.7) breeds of cattle and cows in the peri-urban area (OR?=?0.4; 95% CI 0.2–0.9) were less at risk of being positive reactors. Again, M. avium reactor of 21.7% was observed. In the abattoir, 1797 cattle were examined with 126 lesions suggestive of tuberculosis (TB). Culture/molecular analyses confirmed 2.2% M. bovis and 0.9% NTM infections. Risk factors associated with bovine TB among trade cattle were sex (OR?=?4.0; 95% CI 1.2–13.5) and age (OR?=?0.3; 95% CI 0.1–0.9). We confirm 11.7% prevalence of mycobacterial infections among populations of cattle screened with breed and herd size being major risk factors.  相似文献   
183.
Flunixin is marketed in several countries for analgesia in adult swine but little is known about its efficacy in piglets. Thirty‐two piglets (6–8 days old) were randomized to receive placebo saline (= 11, group CONTROL) or flunixin meglumine intravenously at 2.2 (= 11, group MEDIUM) or 4.4 (= 10, group HIGH) mg/kg, 10 hr after subcutaneous injection of kaolin in the left metacarpal area. A hand‐held algometer was used to determine each piglet’s mechanical nociceptive threshold (MNT) from both front feet up to 50 hr after treatment (cut‐off value of 24.5 newton). Serial venous blood samples were obtained to quantify flunixin in plasma using LC‐MS/MS. A PKPD model describing the effect of flunixin on the mechanical nociceptive threshold was obtained based on an inhibitory indirect response model. A two‐compartmental PK model was used. A significant effect of flunixin was observed for both doses compared to control group, with 4.4 mg/kg showing the most relevant (6–10 newton) and long‐lasting effect (34 hr). The median IC50 was 6.78 and 2.63 mg/ml in groups MEDIUM and HIGH, respectively. The ED50 in this model was 6.6 mg/kg. Flunixin exhibited marked antinociceptive effect on kaolin‐induced inflammatory hyperalgesia in piglets.  相似文献   
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The hindlimb of the grasscutter (Thryonomys swinderianus, Temminck‐1827) was studied using 12 adult (≥6 months) rats of either sex with the mean weights of 1.42 ± 0.20 kg and 0.82 ± 0.13 kg for buck (n = 6) and doe (n = 6), respectively (p < .05). Characteristics of the bones were studied by gross observation after their preparation. Measurements of different segments of the hindlimb were also taken, giving a total average length of 31.80 cm. Correlation coefficients between length of bone and weight of rats were positive (p < .05) in bucks for all bone segments, except the pes (p > .05), whereas those in does were all non‐significant (p > .05), with significant sexual dimorphism in the relationships. The average total number of bones in the hindlimb was 92, with no apparent sexual dimorphism. The bones of the hindlimb revealed important differences and similarities in morphology with those of other rodents. The Os coxae presented a relatively large obturator foramen, formed by the ramus of the ischium and shaft of the pubis. The femur had a body and two extremities with a prominent head, well‐defined neck and trochanter. The fibula, a slender bone with triangular‐shaped proximal extremity, ran down the length of tibia with proximal attachment (via cartilage) and distal fusion, leaving an extensive interosseus space. The pes revealed eight tarsals and four metatarsals; each of the metatarsals showed three phalanges.  相似文献   
187.
We investigated effects of Rendement Napole (RN ) genotype on metabolic markers in Ossabaw pigs fed diets with different levels of dietary fat. Thirty‐two pigs, belonging to either the wild‐type (WT , rn+/rn+) or carrier (CAR , RN ?/rn+) genotypes (n  = 16/genotype), were divided into two dietary groups, (high fat [HF ] or low fat [LF ]) diets, for 12 weeks (n  = 8 pigs/genotype/diet) after which pigs were killed for gene expression analysis by RT ‐PCR . Feeding HF diet caused increased daily gain (ADG ,<  .05) and final body weight (BW ) (<  .05) in comparison with the LF diet (<  .05). Feed efficiency (gain:feed) was higher (<  .05) in pigs on the HF and was higher (<  .05) in CAR pigs compared to WT . There was genotype × diet interaction (=  .05) on final BW such that CAR animals on LF diet had the same final BW as animals of both genotypes on HF diet. Carrier pigs on LF diet had higher (<  .05) average daily gain and gain:feed than WT pigs. There was a trend (<  .08) for a higher feed consumption in pigs on the LF diet. Backfat thickness was higher (<  .01) in pigs on the HF diet. Serum triglyceride was higher (0.62 vs. 0.33 mg/dl, <  .01) in pigs on HF diet. Serum insulin was higher (<  .05) in CAR versus WT pigs (0.40 vs. 0.015 μg/ml). Pigs on the HF diet had a higher (<  .05) serum insulin compared to those on the LF diet (0.032 vs. 0.023 μg/ml). Carnitine palmitoyl transferase 1‐alpha was higher (<  .05) in the longissimus dorsi and semitendinosus muscles of pigs on HF diet. Acyl‐CoA oxidase I was elevated (<  .05) in the liver of pigs on HF diet. Fatty acid synthase was lower in the longissimus dorsi muscle, liver and mesenteric fat (<  .05) of carrier pigs. The RN gene regulates specific metabolic markers in the Ossabaw pigs.  相似文献   
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