372 C. L. OAKLEY A N D G . HARRIET WARRACK

Prophylactic action against T . congolense is slight, as animals are susceptible to inoculation within 4 days after injection of a large dose of the drug, parasites appearing in the blood after the same interval as in untreated controls. After a large dose necrosis of the subcutaneous tissues does not tend to occur.

A striking observation was made in the case of a heavily infected mouse which was convulsed before it received a curative dose. Next day, although convulsions had ceased, the animal seemed to be blind, since unlike a healthy mouse it would if unhindered have walked over the edge of a table ; but in the following two days sight was obviously restored, as this abnormal behaviour ceased.

As regards toxicity, in rabbits a dose of 0.005 g . per kilo. of body weight injected intravenously as a 1 : 400 solution has caused no illness ; 0,013 g. may be fatal at once, but this dose or 0.01 g. may cause immediate illness, with or without convulsions, which is rapidly recovered from, there being apparently no later ill effects.

REFERENCES

BROWNINC, C. H., MORGAN, G. T., ROBB, J. V. M., AND

WALLS, L. P. BROWNING, P. . . . . . CURSON, H. H. . . . . . FOURNEAU, E., TREFOUEL, J.,

Mme. TREFOUEL, BOVET, D., AND KOETSCHET, P.

HORNBY, H. E. . . . . . . IENSCH, H. . . . . . . KING, H., LOURIE, E. M., AND

MORGAN, G. T., AND WALLS,

PARKIN, B. S. . . . . .

YORKE, W.

L. P.

VAN RENSBURG, S. W. J. . . SCHWETZ, J., AND STORGK, N. .

This Journal, 1938, xlvi, 203.

This JournaE, 1938, xlvi, 323. S. African J . Sci., 1926, xxiii, 603. C. R. Acad. Sci., 1933, cxcvi, 1173.

Bet. J., 1919, lxxv, 89. Angew. Ghem., 1937,1, 891. Ann. Trop. Ned. Parasitol., 1938, xxxii,

J . Chern. SOC., 1938, p. 389.

Sixteenth Report of the Director of Veterinary Services and Animal Industry, Union S. Africa, 1930, p. 21.

177.

Onderstepoort J . Vet. Sci., 1938, x, 13. Ann. SOC. Belgemdd. trop., 1930, x, 143.

612.116: 5 9 9 . 3 2 (Mus)

THE BLOOD VOLUME OF THE MOUSE

C. L. OAKLEY and G. HARRIET WARRACK

Wellcome Physiological Research Laboratories, Beckenham, Kent

When mice are used for the titration of toxins or for toxicity tests on biological substances, it is not unusual for 0.5-1 C.C. of protein-containing fluids to be injected intravenously or intraperitoneally. It has frequently been objected that such amounts are large as compared with the blood volume of the animal ; information on the blood volume and its variability in the mouse appears therefore to be of some value.

BLOOD VOLUME OF MOUSE

Dreyer and Ray

von Behring, E. A.*

(1910-11)

373

___-___

19 11.9-29.35 g. 57.7 Mincingandextraction

1 10 g. 61 Injection of antitoxin

(45-7-70) of hemoglobin

Results obtained by other observers are as follows.

Blood

0.0. per kilo. Author 1 z&:fs 1 Weight 1 volumein 1 Method

* We have not seeu this paper and have quoted the tlgures from Erlanger (1921). We are unable to determine whether the value is in g. or C.C. per kilo. The figure which is required for most physiological purposes is the volume rather than the mass of the blood.

Methods

Onc hundred mice (46 males, 54 females) weighing from 5 to 38 g. were washed out by Welcker's method. The animal was anaesthctiscd with a mixture of chloroform and ether and pinned out on a wax plate. The chcst was opened and flooded with 1.6 per cent. oxalate and a 0.04 C.C. heart-blood sample removed with a micrometer syringe and diluted to 4 or 8 C.C. as convenient with 1 : 500 ammonia solution. Larger heart-blood samples should be avoided, as dilution of blood may occw during their removal. The animal was then washed out with 1 per cent. sodium citrate in 0.9 per cent. saline a t 37" C., first through the pulmonary artery and then through the aorta, with massage of the organs and limbs until the organs were free from blood and the washings colourless. The washings were collected, hsmolysed with saponin, made up to a convenient volume, centrifuged and compared with the standard made from the heart-blood sample by means of a calibrated photo-electric colorimeter with a logarithmic scale. Due allowance was made for the opalescence of the washings by taking two colori- metric readings, one with a green (Wratten 58) and one with a red (Wratten 29) filter. The " red " reading, which is almost entirely due to opalescence, was subtracted from the '' green " reading, and the result used for reading from the calibration graph. From the relation between the colour of washings and standard the total blood volume and the blood volume per kilo. were determined.

This method will bc the subject of a further notc by Dr J. W. Trevan.

Results

100 mixed mice (fig. 1).

46 male mice.

The mean blood volume per kilo. is 63.2 C.C.

with a variability of 12.9 per cent. The mean blood volume per kilo. is 63.5 C.C. with a

variability of 11.9 per cent. There is a small but significant negative correlation of -0.38 (P (0.01, Fisher, 1936, table V, A) between the blood volume per kilo. and the body weight.t Following Dreyer and Ray (1910-11) and Chisolm (1911) we have determined a logarithmic relation between the blood volume and the body weight and find the best fit to be given by B.V. = 0.09 B.W.o*ss (fig. 2), which agrees very well with the value obtained by Chisolm for 129 rats, but not with that of Dreyer and Ray for a much

t The weight is the crude weight, without deduction for food in the alimentary canal.

374 C. L. OAKLEY AND G . H . WARRAGK

smaller number of mice.* The correlation coefficient between the logarithm of the blood volume and the logarithm of the body weight is +0-95.

The mean blood volume per kilo. is 62.9 C.C. with a variability of 13.3 per cent. There is no correlation between the blood volume per kilo. and the weight (T = 0.03, P>O.I). In view of the finding in the males this seemed to need some explanation.

Though no mome washed out was pregnant we had taken no trouble to make sure that our females were virgins. We thought it possible that the increase in blood volume per kilo. which is generally believed to occur in pregnancy might persist into the puerperium, in which case the larger

54 female mice.

A- Am+ r d m /?- * 46616 -0.JP 0.120 f

$ 54 99 +o.os 0 IJC - ?

8 ?

5 l 0 15 20 25 30 35 IK)

+--V+-~------,

FIG. 1.-Relation between blood volume per kilo. and body weight in 100 normal mice.

fcmales which were more likely to have had litters would show a dispropor- tionate number with a high relative blood volume. Thus the drop in blood volume per kilo. with increasing weight which, on the analogy with males, might be expected in females would be obscured.

We therefore washed out 20 mice in various stages of pregnancy, and 10 at various times post partum. Great care was taken to wash out the

* Dreyer and Ray’s results are on the average lower than ours; this may be due to the use of the mincing method, which we consider does not extract all the haemoglobin from the vessels. The best fit for their figures is given by B.V. = 0.146 B.W.O.‘l.

BLOOD VOLUME OF MOUSE 375

d.1 07 09 09 1 0 I J 12 I 5 C4 I5 I 6

---+.By @+A

FIG. 2.-Relation between log. blood volume and log. body weight in 46 male mice. The best fit is given by B.V. = 0.09 B.W. O.**.

TABLE I.-Blood volume per kilo. in pregnant mice

[other’s weight including fcetuses

8. 31.62 31.65 31.67 31.70 31.74 31.83 32.05 32.99 34.81 35.00 35.86 35.96 36.3 36-6 37.16 37.3 37.96 39.11 39-11 47.6

Weight of fetuses

e. 0.5 1.66 0.32

< 0.05 2.57 0.55 2.59 1.93 1.25 4-9 5.3 8.95 0.51 4.79 2.92 9.1 5.62 2.3 6.91

13.23

Blood volume iu C.C. per kilo. mother’s weight including

fetuses

71.7 59.7 65.0 69.1 68.3 64.1 77.1 67.3 72.1 66.0 60.0 61.5 78.0 68.3 74.8 61.4 64.8 68.6 61.9 56-0

Mean = 67.8 c.c., not sig- nificantly greater than the mean of the 54 norma. females

Blood volume in C.C. per kilo. mother’s weight excluding

fcetuses

72.9 63 .O 65.7 69.1 74.8 65.2 84.1 71.5 74.8 76.7 70.3 81.8 79.1 78.6 81.1 81.2 76.1 73.5 75.1 77.4

Mean 74.6 c.c., significantly greater than the mean of the 54 normal femalee

376 G. L. OAKLEY AND C. H . WARRACK

uteri, after which the fetuses with the placentz and membranes were removed and weighed. Table I shows that the blood volume per kilo. of the pregnant mice was only slightly higher than normal if the weight of the fetuses was included in the mother’s weight, but was uniformly high if the fetal weight was subtracted. Fig. 3 shows that there is a fair correlation ( r = 0.51) between the blood volume per kilo. of mother’s weight less fetuses and the fetal weight ; the two sets of results taken together show that the blood volume of the pregnant female mouse is roughly what would be expected if the fetuses were part of the mother’s tissues.

a

a

a

a #

a a 0

0

a

a

# a

a

& 0 2. 4 L 8 10 12 14

>----*F f + A$--- + FIG. 3.-Relation between blood volume per kilo. mother’s weight less fetuses

and the fatal weight.

TABLE 11.-Blood volume per kilo. in post-partum female mice

I Blood volume in O.C. per kilo. Mother’s weight Time post parturn

30.18 33.14 28.75 27.28 25.35 29.93 28.08 34.48 26.05 23.6

I

I

<1 day < I ,, (1 ,,

1 ,I

1 ,7

2 days 2 9 ,

7 10- 1 i’days 10-14 ,,

67.9 73.3 71.6 60.8 72.6 75.2 70.9 73.3 60.7 70.0

THROMBO-ANGIITIS OBLITERANS I N A HORSE 377

The blood volume of mice post partum shows that the increased blood volume per kilo. of pregnant female mice is retained, at any rate in some animals, for as long as 10-14 days after parturition (table 11). This would clearly be advantageous to the mouse, which normally goes into estrus and becomes pregnant again immediately after parturition.

Summary 1. The average blood volume per kilo. of the mouse is 63.2 c.c., with a

variability of 12.9 per cent. The figures for the sexes are : 46 males, mean 63.5 c.c., with a variability of 11-9 per cent. ; 54 females, mean 62.9 c.c., with a variability of 13.3 per cent. The best fit for the males is given by

2. There is a small negative correlation between the blood volume per kilo. and the weight in male mice. I n non-pregnant female mice there is no such correlation.

3. Pregnant mice have such a blood volume as would be expected if the fetuses were part of the maternal tissues i.e. the mother provides a stroma for the fetuses.

4. The increased blood volume per kilo. of the pregnant females less fetuses persists into the puerperium in some mice for at least 10 days.

B.V. = 0.09 B.W.O'SS.

REFERENCES

CHISOLM, R. A. . . . . . 1911. Quart. J . Exp. Physiol., iv, 207. DREYER, G., AND RAY, W.. . 1910-11. Philos. Trans., B., cci, 133. ERLANGER, J. . . . . . 1921. Physiol. Rev., i, 177. FISHER, R. A. . . . . . 1936. Statistical methods for research

workers, 6th ed., Edinburgh and London.

616. 13-002-00~.6 : 6 3 6 . I

THROMBO-ANGIITIS OBLITERANS IN A HORSE

J. R. M. INNES and J. W. WHITTICK

Institute of Animal Pathology, Cambridge University

(PLATE XLII)

There appears to be no record of the occurrence of arterial disease in animals analogous to that originally described in man by Buerger (1908) as thrombo-angiitis obliterans. Nieberle and Cohrs (1931) state that the disease does not occur in animals, while Holz (1938) uses the term erroneously as a synonym for endarteritis obliterans in describing the vascular changes in equine infectious anEmia. Intermittent claudication is well known to occur in horses and a good description of such cases is given in Hutrya, Marek and Manninger (1938). In enumerating the causes of the clinical entity, these authors do not mention any condition which might be regarded as Buerger's disease. At present the commonest cause of claudication in horses is thought to be thrombosis of the abdominal aorta and its main branches secondary to invasion of the walls by the larvae of Strongylus

JOURN. OF PATH.-VOL. L 2 B