JPH04215033A - Metabolic cage for experimented animal - Google Patents

Abstract

PURPOSE:To accommodate an animal in a cage regardless of its size for a pharmacokinetic test and collect its urine, feces and exhalation fractionally with efficiency. CONSTITUTION:In an animal accommodating chamber A provided at the upper part of a metabolic cage, the feces and urine of an animal fall passing a bottom floor part 5. Then in a feces collecting chamber B below, the feces is received at a bottom floor part 6, and the urine falls passing the bottom floor part 6 and stays in an urine collecting container 10 in an urine collecting chamber C. The inside of the matabolic cage is sucked by a suction pump, and exhalation passes an exhalation collecting induction tube 8 from the feces collecting chamber B and the urine collecting chamber C and is dissolved into trap liquid in a trap.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to metabolic cages for experimental animals, and more particularly to cages for housing animals administered with test drugs and for separately collecting urine, feces, and exhaled air in pharmacokinetic studies. .

0002

[Prior Art] In pharmacokinetic studies, which are a part of drug safety testing, a test drug labeled with a radioactive isotope such as 14C or 3H is usually administered to experimental animals, and its absorption, distribution, metabolism, etc. Examine excretion, etc.

Regarding excretion, it is necessary to separately collect urine, feces, and exhaled air, measure the radioactivity of each, and clarify the excretion route and excretion rate of the administered test drug. It is also necessary to analyze excreta to reveal its chemical structure and estimate metabolic pathways. To achieve this goal, a metabolic cage is required that can clearly separate urine, feces, and exhaled air and collect them without loss.

[0004] Such metabolic cages for separately collecting urine, feces, and exhaled air include those for small rodents such as rats and mice. The feces of these rodents are hard, rugby ball-shaped, and are rolled into a feces container at the bottom of the cage to be separated from urine.

[0005] However, this cage cannot accommodate large animals such as dogs and monkeys. Even if such cages are enlarged to accommodate larger animals, the feces of such animals are soft and difficult to roll, so they stick to the cages and cannot be collected efficiently.
Furthermore, since exhaled gas (usually carbon dioxide) is heavier than air, exhaled gas accumulates in large feces and urine containers, making it impossible to accurately collect exhaled breath. Therefore, there has been a demand for the development of metabolic cages that can efficiently collect urine, feces, and exhaled air from mammals, birds, and other animals, regardless of whether they are small or large.

[0006]

[Means for Solving the Problems] Under these circumstances, the present inventors have conducted extensive research to develop a metabolic cage that satisfies the above requirements, and as a result, have completed the present invention.

That is, the present invention provides an animal housing chamber (A) having an air intake 3 at the upper part and a bottom floor part 5 on which excrement and urine fall, and an animal housing chamber (A) formed at the lower part of the animal housing chamber (A) to allow the excrement to fall. A feces collection chamber (B) having a bottom floor 6 through which urine can pass and fall, and a urine collection chamber (C) disposed at the lower part of the feces collection chamber (B) to receive urine. At the same time as in the urine collection chamber (C), an upper exhaled breath collection guide tube 8 for connecting to a trap equipped with a suction pump is placed in the above-mentioned feces collection chamber (B) or in a position facing the feces collection chamber (B). A metabolic cage for laboratory animals is provided, which is equipped with a lower exhaled breath collection guide tube 11 and is a closed system except for the air intake port 3 and exhaled breath collection guide tubes 8 and 11.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be further explained below with reference to drawings showing embodiments. The animal housing chamber (A) and the fecal collection chamber (B) formed below are integrated and covered with a wall made of a transparent material, such as acrylic resin, that can be sealed and observed from the outside. The wall has an animal door 1 in the front part of the animal accommodation room (A), and a bottom drawer door 2 in the front part of the feces collection room (B), which are closed when closed. It has a sealable structure to prevent the air inside the cage from leaking outside.

The animal housing room (A) has an air intake 3 at the top and a feeding/watering section 4 equipped with a feeder and a waterer at the front. This feeding/watering section 4 can be opened and closed so that animals can be taken in and taken out. Feeding in this example
The water supply section 4 is an example for dogs, and can have an appropriate shape depending on the type of animal. Moreover, the animal accommodation chamber (A) has a bottom floor part 5 through which excrement and urine are allowed to fall. The bottom floor 5 is preferably made of, for example, round metal rods arranged in a drainboard shape at relatively large intervals so that soft feces of dogs, monkeys, etc. can easily pass through.

[0010] Feces collection room (B) below this animal housing room (A)
has a bottom floor part 6 that receives feces that has fallen from the animal accommodation room (A) and allows only urine to pass therethrough. The bottom floor 6 is preferably made of a net that is fine enough to allow urine to easily pass through, for example, on which excrement that has fallen from above is deposited. Feces collection room (B)
The front part has a urine scattering prevention door 7, and if necessary, this door and the bottom drawer door 2 can be opened, and the bottom bed 6 can be pulled out to collect feces. This urine scattering prevention door 7 is provided as necessary to prevent urine and feces from being sucked together with exhaled air from the upper exhaled breath collection guide tube 8, which will be described later. It does not have a sealed structure that cuts off the flow of air to the guide tube 8.

The upper breath collection guide tube 8 is connected to a trap equipped with an external suction pump. However, it may be directly attached to the feces collection chamber (B) as long as it is located below the bottom floor 5 of the animal housing chamber (A). Further, the lower part of the upper exhaled breath sampling guide tube 8 may have a funnel-shaped structure for discharging water spilled from the water supply device, as shown in FIG. 1 or 2.

[0012] The urine collection room (C) has a urine receptacle 9 and a urine collection container 10.
Consisting of The urine receiver 9 is funnel-shaped in order to guide the urine that has passed through the feces receiving net 6 to the urine collection container 10. The urine collection container 10 has a lower breath collection guide tube 11 for connecting to a trap equipped with an external suction pump, and can be removed from the urine receiver 9 as appropriate to collect urine. The lower exhaled breath collection guide tube 11 can be attached to any position in the urine collection chamber (C), but in order to further reduce the retention of exhaled air, it is preferably installed above the urine water level of the urine collection container 10. In this case, since the tube 11 is located near the urine water surface, if the tube 11 is made too thick, the flow rate of air in the urine collection container (C) will increase and the urine will evaporate, making it impossible to perform accurate measurements. It is preferable that the tube be thinner than the tube 8.

In this embodiment, the animal housing room (A), the feces collection room (B), and the urine collection room (C) are completely sealed except for the air intake port 3 and the upper and lower breath collection guide tubes 8 and 11. It is organized into a system.

[0014]

[Operation] When using the metabolic cage of the present invention, the two exhaled breath collection guide tubes 8 and 11 coming out of the cage are merged into one by further interposing a connecting tube as necessary, as shown in FIG.
It is connected to a trap with an external suction pump 13 as shown in FIG. Since the inside of the trap is suctioned by the pump 13, the air introduced from the air intake port 3 is sent to the animal accommodation chamber (A), the feces collection chamber (B), the upper breath collection guide pipe 8, or Animal holding room (A), fecal collection room (B)
), the space inside the urine collection chamber (C) and the lower exhaled breath collection guide tube 1
It reaches the trap via 1 and is dissolved and collected in the trap liquid. In the cage of the present invention, the urine collection chamber (C) also has an exhaled breath collection guide tube, so exhaled air does not accumulate in the interior space of the urine collection chamber (C), and carbon dioxide, etc. in exhaled breath can be collected accurately. It is possible.

The trap is not particularly limited and any commonly used trap can be used, but it is preferable to have a trap liquid replenishment pipe 12 as shown in FIG. The trap liquid is not particularly limited, and ordinary ones can be used, but when used for dissolving carbon dioxide, for example, monoethanolamine aqueous solution (20 to 100%), sodium hydroxide aqueous solution (0.5 to 1N), etc. is used. Two or three traps may be arranged in series as shown in Figure 3.
Further, two or more trap rows may be arranged. When two or more trap rows are arranged, by switching the trap row used at regular intervals, efficient continuous measurement can be performed without interrupting exhaled breath collection even when draining and replenishing the trap liquid. I can do it.

[0016]

[Effects of the Invention] Since the cage of the present invention is constructed as described above, it can accommodate large animals such as dogs and monkeys, and also prevents soft feces from adhering to the cage and exhaled breath from entering the urine collection chamber. Since there is no retention, it can be used regardless of the size or type of animal.
Urine, feces, and exhaled breath can be collected efficiently and accurately.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing an example of a metabolic cage for laboratory animals according to the present invention.

FIG. 2 is a partially cutaway front view showing an example of the metabolic cage for laboratory animals of the present invention.

FIG. 3 is a diagram showing an example of a trap equipped with a suction pump for collecting gas contained in exhaled breath collected from a metabolic cage for laboratory animals according to the present invention.

[Explanation of symbols]

1. Animal door 2 Bottom floor drawer door 3 Air intake 4 Feeding/water supply department 5 Bottom floor part 6 Bottom floor part 7 Urine scattering prevention door 8 Upper exhaled breath collection guide tube 9 Urine receiver 10 Urine collection container 11 Lower breath collection guide tube 12 Trap liquid replenishment pipe 13 Pump

Claims (1)

[Claims] Claim 1: An animal holding chamber (
A), and a feces collection chamber (A) having a bottom floor 6 formed at the lower part of the animal housing chamber (A) to receive feces and allow urine to pass through and fall.
B), and a urine collection chamber (C) which is arranged below the feces collection chamber (B) and receives urine, and which faces the feces collection chamber (B) or the feces collection chamber (B). An upper breath collection guide tube 8 for connecting to a trap equipped with a suction pump is attached to the urine collection chamber (C), and a lower breath sample guide tube 11 is attached to the urine collection chamber (C). A metabolic cage for laboratory animals, characterized in that it is a closed system except for tubes 8 and 11.