The blood volume of mammals as determined by experiments upon rabbits, guinea-pigs, and mice : and its relationship to the body weight and to the surface area expressed in a formula / by Georges Dreyer and William Ray.

  • Dreyer, G. (Georges), 1873-1934.
Date:
[1910]
Catalogue details

Licence: In copyright

Credit: The blood volume of mammals as determined by experiments upon rabbits, guinea-pigs, and mice : and its relationship to the body weight and to the surface area expressed in a formula / by Georges Dreyer and William Ray. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    7/30 (page 137)
    In employing this method it is absolutely essential to use animals that have not been bled before. Guinea-pigs and Mice.—The Welcker method was employed. The sample of original blood was taken from the heart after the animal had been anaesthetised, and diluted in the usual way. In the mice, the original sample contained, however, only 0-01 c.c. of blood. The animal was then bled to death into distilled water which contained some “ Hirudin.” The alimentary canal and skin were then carefully removed, and the muscles, heart, liver, spleen, etc., were finely clipped and soaked in distilled water for about a quarter of an hour. The first and second washings thus obtained were decanted off and were quite clear. Fresh distilled water was then added and the remains of the animal were cut into fine pieces and gently squeezed in a porcelain mortar with porcelain pestle. The tissues were not ground. The fluid was then decanted off through fine linen. This third washing was always quite turbid, and was always kept distinct from the clear washings. As it was found impossible to render this turbid washing clear without losing a considerable amount of haemoglobin, and as it is impossible accurately to compare clear and turbid solutions as regards colour strength, the standard used for estimating the amount of haemoglobin in these turbid washings was always brought to the same degree of turbidity by the addition of a small quantity of pure olive oil and shaking. We made preliminary control experiments to prove that this method would give reliable results. In all of these various methods, the accurate determination of the haemoglobin is essential, and for this purpose we have invariably used a Meisling haemoglobinometer. The extreme delicacy and accuracy of this instrument, described by a number of observers, we have amply confirmed. We will first deal with the experiments upon rabbits made by ourselves and other observers, and finally give our results upon guinea-pigs and mice. In all tables the body weight of the animals is “ Rohgewicht ” in grammes, that is to say that the weight of the contents of the alimentary canal is not deducted. The blood volume is given in cubic centimetres. The haemoglobin is always expressed as percentages of the amount normal in man (man = 100 per cent.). In Table I are given the blood volumes found in 22 rabbits, varying in weight from 670 to 3250 grammes. In the experiments marked by an asterisk the blood volumes were estimated by following the fall in haemoglobin after bleeding, in the others by washing out. From this table it is evident that the ratio of blood volume to body weight decreases as the body weight of the animal increases. If we attempt to find the best mathematical expression for these experiments, it will be seen that the body weight to the nth power, divided by the blood volume, gives a constant, and it will be further seen that the power n is approximately two-thirds. As Meeh has found that the surface area of an animal is equal to a constant multiplied by the body weight to the VOL. CCI.—B. T