Objective To evaluate the cardiopulmonary and sedative effects of xylazine alone or in combination with methadone, morphine or tramadol in sheep. Study design Experimental, prospective, crossover, randomized, blinded study. Animals Six Santa Inês breed sheep (females) aged 12 ± 8 months and weighing 39.5 ± 7.4 kg. Methods Sheep were sedated with each of four treatments in a randomized, crossover design, with a minimum washout period of 7 days between treatments. Treatments were: X [xylazine (0.1 mg kg−1)]; XM [xylazine (0.1 mg kg−1) and methadone (0.5 mg kg−1)]; XMO [xylazine (0.1 mg kg−1) and morphine (0.5 mg kg−1)], and XT [xylazine (0.1 mg kg−1) and tramadol (5 mg kg−1)]. Each drug combination was mixed in the syringe and injected intravenously. Sedation, heart rate (HR), mean arterial blood pressure (MAP), rectal temperature (RT°C), respiratory rate (fR), arterial blood gases and electrolytes were measured before drug administration (T0) and then at 15 minute intervals for 120 minutes (T15–T120). Results Heart rate significantly decreased in all treatments compared with T0. PaCO2 values in XM and XMO were higher at all time points compared with T0. In treatments X and XM, pH, bicarbonate (HCO3−) and base excess were increased at all time points compared with T0. PaO2 was significantly decreased at T15–T75 in XM, at all time points in XMO, and at T15 and T30 in XT. Sedation at T15 and T30 in XM and XMO was greater than in the other treatments. Conclusions and clinical relevance The combinations of methadone, morphine or tramadol with xylazine resulted in cardiopulmonary changes similar to those induced by xylazine alone in sheep. The combinations provided better sedation, principally at 15 minutes and 30 minutes following administration.

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OBJECTIVE To evaluate cardiopulmonary, sedative, and antinociceptive effects of dexmedetomidine combined with commonly administered opioids in dogs. ANIMALS 8 healthy Beagles. PROCEDURES Dogs were sedated by IM administration of each of 7 treatments. Treatments comprised dexmedetomidine (0.01 mg/kg; Dex) and the same dose of dexmedetomidine plus butorphanol (0.15 mg/kg; Dex-But), meperidine (5 mg/kg; Dex-Mep), methadone (0.5 mg/kg; Dex-Meth), morphine (0.5 mg/kg; Dex-Mor), nalbuphine (0.5 mg/kg; Dex-Nal), or tramadol (5 mg/kg; Dex-Tram). Cardiorespiratory and arterial blood gas variables and sedative and antinociceptive scores were measured before drug injection (time 0; baseline) and at 15-minute intervals for 120 minutes. RESULTS Heart rate was reduced at all time points after injection of Dex-But, Dex-Mep, Dex-Meth, and Dex-Mor treatments. There was a significant reduction of mean arterial blood pressure for Dex-But, Dex-Mep, and Dex-Mor treatments at all time points, compared with baseline. There was a significant decrease in respiratory rate, compared with the baseline value, for Dex, Dex-But, Dex-Meth, and Dex-Tram treatments from 15 to 120 minutes. A significant decrease in arterial blood pH was detected from baseline to 120 minutes for all treatments, with differences among Dex, Dex-Mep, and Dex-Mor. Reduction in Pao was greater for the Dex-Mep treatment than for the other treatments. The highest sedation scores were detected for Dex-Mep and Dex-Meth treatments. Antinociceptive effects were superior for Dex-But, Dex-Meth, Dex-Mor, and Dex-Nal treatments. CONCLUSIONS AND CLINICAL RELEVANCE Drug combinations caused similar cardiorespiratory changes, with greater sedative effects for Dex-Mep and Dex-Meth and superior antinociceptive effects for Dex-But, Dex-Meth, Dex-Mor, and Dex-Nal.

The sedative and selected cardiopulmonary effects of acepromazine alone or in combination with methadone, morphine, or tramadol were compared in sheep. Six ewes were randomly assigned to treatments: A (0.05 mg/kg acepromazine), AM (A plus 0.5 mg/kg methadone), AMO (A plus 0.5 mg/kg morphine), and AT (A plus 5 mg/kg tramadol). Parameters were assessed before sedative drug administration (baseline) and every 15 minutes thereafter, for two hours. Treatments A and AM were associated with increases in sedation score for 60 minutes and treatments AMO and AT for 30 minutes; however, there were no significant differences between treatments. There was a decrease in mean arterial pressure compared to baseline values in treatment A at 15, 45, 60, and 90 minutes, in treatment AM at 15 minutes, and in treatment AT from 45 to 120 minutes. Arterial blood carbon dioxide pressure increased at all time points in all treatments. Arterial oxygen pressure decreased in treatment AMO at 15, 30, and 120 minutes and in treatment AT at 15–45, 105, and 120 minutes, compared to baseline. Acepromazine alone causes a level of sedation similar to that observed when it is coadministered with opioids methadone, morphine, and tramadol. These combinations did not cause clinical cardiopulmonary changes.

This study analysed the effect of pastes formulated with calcium hydroxide P.A. and different vehicles (saline solution -paste A and Copaifera langsdorffii Desfon oil -paste B) on oral microorganisms and dentin bridge formation in dogs. The antimicrobial action of the pastes and their components was analysed by the minimum inhibitory concentration in agar gel RESUMO Foi avaliada a ação de pastas formuladas com hidróxido de cálcio P.A. e diferentes veículos (solução fisiológica -pasta A e óleo de Copaifera langsdorffii Desfon -pasta B) sobre microrganismos bucais e formação de ponte dentinária em cães. A ação antimicrobiana das pastas e de seus componentes individuais foi avaliada pela técnica da concentração inibitória mínima pela diluição em ágar. Os materiais foram diluídos e avaliados contra quinze cepas padrão de microrganismos relacionados a doenças endodônticas. Os microrganismos foram cultivados e, após a incubação, os dados foram analisados (Anova OneWay, Tukey, P≤0,05). Para a avaliação da formação de ponte dentinária, quatro incisivos superiores de dez animais foram tratados, sendo dois capeados com pasta A (GA) e dois com a pasta B (GB). Após 90 dias, os dentes foram extraídos para