Minimally invasive technique for intrathecal administration of morphine in rats: practicality and antinociceptive properties.

The intrathecal (IT) route of administration represents a means to reduce the dose of morphine administered for analgesia, potentially minimizing interactions between opioid effects and experimental outcomes. Perceived technical difficulty, and previously described invasive methods, may limit its use. This report describes a minimally invasive technique for IT administration of morphine by direct transcutaneous lumbosacral puncture in rats; and assesses antinociceptive properties of morphine in anaesthetized rats.

A surgical approach in the treatment of preputial gland abscesses in mice.

Background: Preputial gland infection is a common occurrence in non-breeder male mice and can lead to abscesses. This report describes a surgical approach to treating and preventing this condition.

Results: Surgical removal of the glands was undertaken in 258 male C3H/HeNHsd mice.

Rapid and equivalent systemic bioavailability of the antidotes HI-6 and dicobalt edetate via the intraosseous and intravenous routes.

Background: Rapid and effective administration of antidotes by emergency medical responders is needed to improve the survival of patients severely poisoned after deliberate release of chemical weapons, but intravenous access is difficult to obtain while wearing personal protective equipment and in casualties with circulatory collapse. To test the hypothesis that rapid and substantial bioavailability of the antidotes HI-6 oxime and dicobalt edetate can be achieved via the intraosseous (IO) route, plasma concentration-time profiles of these antidotes were compared after administration by the intravenous and IO routes in a minipig animal model.

Methods: 12 male Göttingen minipigs were randomly allocated to receive 7.

A comparison of medetomidine and its active enantiomer dexmedetomidine when administered with ketamine in mice.

Background: Medetomidine-ketamine (MK) and dexmedetomidine-ketamine (DK) are widely used to provide general anaesthesia in laboratory animals, but have not been compared directly in many of these species, including rodents. This study aimed to compare the onset and depth of anaesthesia, and changes in vital signs, after intraperitoneal (IP) or subcutaneous (SC) administration of ketamine (75 mg kg(-1)) combined with medetomidine (1 mg kg(-1)) or dexmedetomidine (0.5 mg kg(-1)) using a randomised semi-crossover design with ≥ 48 hours between treatments in 10 male and 10 female mice.

Evaluation of EMLA cream for preventing pain during tattooing of rabbits: changes in physiological, behavioural and facial expression responses.

Background: Ear tattooing is a routine procedure performed on laboratory, commercial and companion rabbits for the purpose of identification. Although this procedure is potentially painful, it is usually performed without the provision of analgesia, so compromising animal welfare. Furthermore, current means to assess pain in rabbits are poor and more reliable methods are required.

Combining nitrous oxide with carbon dioxide decreases the time to loss of consciousness during euthanasia in mice--refinement of animal welfare?

Carbon dioxide (CO(2)) is the most commonly used euthanasia agent for rodents despite potentially causing pain and distress. Nitrous oxide is used in man to speed induction of anaesthesia with volatile anaesthetics, via a mechanism referred to as the "second gas" effect. We therefore evaluated the addition of Nitrous Oxide (N(2)O) to a rising CO(2) concentration could be used as a welfare refinement of the euthanasia process in mice, by shortening the duration of conscious exposure to CO2.