A rat restraining cage for IV infusion in epigastric flap studies

A rat restraining cage is described for use in epigastric flap studies requiring IV infusions of 24 hours or more. The device is simple, effective, and reliable; it appears to be less stressful for the rat than other methods of restraint.     

A method of restraining rats for intravenous injection using a flexible plastic bag

Intravenous injections via the tail vein of the rat were made easier by using cone-shaped plastic bags. The technique is simple and less traumatic for the rat.     

A plastic restraining device for rodents

A simple device was fabricated from a single piece of plastic to restrain several different species of rodents. The device served as a useful adjunct for numerous research, medical and teaching applications.     

A custom restraining device for small animals

A full-body restraining device was constructed that permits the short-term recording of physiologic data (respiration, electrocardiogram, arterial blood pressure, and electroencephalogram) in unanesthetized rats. A plaster cast of a freshly killed 160 g rat was made and cut to yield a base and two side pieces. Using the assembled cast as a custom tray, an alginate impression of the rat was taken. Replicas of the cast pieces were then made of plastic. Animals to be tested were anesthetized briefly, placed in the restraining device, and allowed to waken. Results with 400 animals demonstrate the feasibility of recording physiologic data during acute studies in conscious rats.     

A novel design for an instrumented stairway

Kinetics during stair ambulation is currently studied via either the use of sensing elements embedded in the steps of the stairway or simple rigid blocks of different height positioned on top of existing force platforms, typically embedded in a walkway for gait analysis. Neither of these approaches is truly satisfactory for gait analysis laboratories. The first one is expensive and requires setting up a dedicated space. The second approach is limited by the number of platforms utilized in the laboratory for evaluating level walking. This communication proposes a novel design, referred to as "interlaced stairway", that allows one to measure ground reaction force and position of the center of pressure (CoP) for four foot contacts during stair ambulation using only two force platforms embedded in a walkway. Accuracy and precision of the CoP estimates and natural frequency of the stairway structure were derived from experimental data. Test results indicate that the interlaced stairway structure does not appreciably reduce the quality of the measures gathered by the existing force platforms. Specifically, the estimated CoP coordinates show good agreement with the horizontal coordinates of the geometric center of the calibration object utilized to assess accuracy and precision of the CoP estimates (max difference < 6 mm). The natural frequency of the stairway structure is lower than the one for the unloaded force platform but higher than the frequency components of interest in stair ambulation analysis.     

Design of a metabolic cage for infant rats.

A glass metabolic cage was designed for studies involving newborn rats and small animals up to about 15 g. The metabolic chamber is a jacketed tube, open on both ends and closed with 0-ring clamps. Water is circulated around the cage to maintain a constant and physiologic chamber temperature. Information about the metabolic pathway of nutrients and drugs can thus be studied, and the effects of drugs on metabolism of substrates to CO2 can also be assessed in the newborn animal.     

The cage preferences of laboratory rats

Preference tests were used to assess a range of enrichment options for rats kept under standard New Zealand (and similar) caging conditions. The rats did not show significant preferences for most of the options, over an empty cage. The exceptions were shredded paper, a nesting box and a semi-enriched condition incorporating a range of modifications. These cage modifications are recommended for the enrichment of laboratory rats.     

A fluorocarbon-coated diuresis cage for rodents

A simple and inexpensive rat diuresis cage is described. It may be constructed from thin aluminium sheeting in combination with a standard laboratory holding cage. Application of a low resistance PTFE coating reduces urine losses to a level better than a leading commercial design. Some physiological strain comparison data obtained using the cage are given.     

A restraining system for rhesus monkeys used in space research

A new chronic restraining system has been designed specifically for male rhesus monkeys (8–13 kg) housed in weightlessness for scientific purposes. The restraining system consists of a coat (jacket and skirt) and a chair. The system separates the thorax from the lower part of the body, and allows large movements of the upper part of the body. The macaque can feed and groom itself, and can also sleep in close-to-normal position.     

Physiological profile of juvenile rats: effects of cage size and cage density

Although there is a general consensus that housing conditions affect the well-being of laboratory animals, the ideal cage size and density for housing laboratory rodents has not been established. The authors investigated the effects of cage size and cage density on growth, organ development, metabolic profile, and hemogram in juvenile Sprague-Dawley rats. Larger cages and increased cage density were associated with depressions in body weight and in the weights of several organs. In general, increasing group size and density correlated more strongly with detrimental effects on the growth of females than males, although hemogram values indicated that males are more prone to emotional stress and immune suppression than females in response to increasing group size and crowding.