J Am Assoc Lab Anim
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J Am Assoc Lab Anim · Jan 2012
Sedation or inhalant anesthesia before euthanasia with CO2 does not reduce behavioral or physiologic signs of pain and stress in mice.
CO(2) administration is a common euthanasia method for research mice, yet questions remain regarding whether CO(2) euthanasia is associated with pain and stress. Here we assessed whether premedication with acepromazine, midazolam, or anesthetic induction with isoflurane altered behavioral and physiologic parameters that may reflect pain or stress during CO(2) euthanasia. Mice were assigned to 1 of 6 euthanasia groups: CO(2) only at a flow rate of 1.2 L/min which displaces 20% of the cage volume per minute (V/min; control group); premedication with acepromazine (5 mg/kg), midazolam (5 mg/kg), or saline followed by 20% V/min CO(2); induction with 5% isoflurane followed by greater than 100% V/min CO(2) (>6L/min); and 100% V/min CO(2) only (6 L/min). ⋯ Compared with 20% V/min CO(2) alone, premedication with acepromazine or midazolam did not significantly alter behavior but did induce significantly higher c-fos expression in the brain. Furthermore, the use of isoflurane induction prior to CO(2) euthanasia significantly increased both behavioral and neuromolecular signs of stress. The data indicate that compared with other modalities, 20% V/min CO(2) alone resulted in the least evidence of stress in mice and therefore was the most humane euthanasia method identified in the current study.
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J Am Assoc Lab Anim · Jan 2012
Validity of the modified richmond agitation-sedation scale for use in sedated, mechanically ventilated Swine.
A valid and reliable scale for assessing level of sedation would facilitate appropriate sedation management in a porcine intensive care unit (ICU) model. The Richmond Agitation-Sedation Scale (RASS) is used often for human ICU patients. The purpose of this study was to estimate the content validity of the modified RASS for use in sedated, mechanically ventilated swine. ⋯ The item CVI varied from 0.50 to 0.88; scale CVI was 0.66. Because these values did not meet the a priori criterion, we concluded that the modified RASS does not have sufficient evidence of content validity for use with swine. The reliability of the modified RASS will be tested in the porcine ICU model, and experience with its use in swine will inform refinement of the scale descriptors for repeat assessment of content validity.
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J Am Assoc Lab Anim · Nov 2011
Comparative StudyDetermination of plasma fibrinogen concentrations in beagle dogs, cynomolgus monkeys, New Zealand white rabbits, and Sprague-Dawley rats by using Clauss and prothrombin-time-derived assays.
The most widely used technique for determination of fibrinogen concentration is the Clauss fibrinogen (FIB(Clauss)) assay, which measures the clotting time of plasma after addition of excess thrombin. More recently, the PT-derived fibrinogen (FIB(PT)) assay has been developed, based on the relationship between fibrinogen concentration and the kinetics of clot formation during the prothrombin time. The objective of this study was to compare the fibrinogen concentration determined by the FIB(Clauss) and FIB(PT) assays in citrated plasma samples from healthy dogs (n = 40), monkeys (n = 40), rabbits (n = 26), and rats (n = 58) by using an automated coagulation analyzer. ⋯ In conclusion, the FIB(PT) assay is a rapid and economical method for estimating fibrinogen concentration in plasma samples from dogs, monkeys, rabbits, and rats. However, it should not be used without restriction. Further studies are required to investigate the performance of this assay in animals with various pathologic states, including coagulopathy, dysfibrinogenemia, and hypo- or hyperfibrinogenemia.
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J Am Assoc Lab Anim · Jul 2011
Randomized Controlled TrialEffects of multimodal analgesia on the success of mouse embryo transfer surgery.
Multimodal analgesia is promoted as the best practice pain management for invasive animal research procedures. Universal acceptance and incorporation of multimodal analgesia requires assessing potential effects on study outcome. The focus of this study was to assess effects on embryo survival after multimodal analgesia comprising an opioid and nonsteroidal antiinflammatory drug (NSAID) compared with opioid-only analgesia during embryo transfer procedures in transgenic mouse production. ⋯ A total of 99 surgical sets were analyzed, comprising 199 Crl:CD1 female mice and their 996 offspring. Neither yield (pups weaned per embryo implanted in the surgical set) nor birth rate (average number of pups weaned per dam in the set) differed significantly between the CB and VB conditions. Multimodal opioid-NSAID analgesia appears to have no significant positive or negative effect on the success of producing novel lines of transgenic mice by blastocyst transfer.
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J Am Assoc Lab Anim · May 2011
Performance and longevity of a novel intraosseous device in a goat (Capra hircus) model.
We performed 2 studies to assess the function and longevity of a novel intraosseous catheter device. For study 1, 9 goats were assigned to 3 groups (intraosseous catheter in the proximal humerus, intraosseous catheter in the proximal tibia, or standard jugular catheter). Devices in the tibia remained in place for less time than did those in the humerus, and no goats exhibited radiographic evidence of resulting damage or structural change in surrounding bone. ⋯ Bloodwork indicated mild elevations of WBC counts from baseline in some cases. Bacterial growth was found in samples from 4 of 18 goats at various time points. Our study indicated that intraosseous catheters may remain safely in place for more than 24 h, but animals should be monitored closely for negative side effects for several days after removal.