SOME OBSERVATIONS ON RICKETS IN PUPS
By K. RAGHAVACHARI, G.M.V.C., Imperial Veterinary Research Institute, Mukteswar
(Received for publication on 4 May 1942)
BEFORE Mellanby [1921] had conclusively estab-
lished that the antirachitic vitamin was intimately
connected with the aetiology of rickets in dogs,
several hypotheses were postulated to explain the
cause of rickets in man and animals. The earlier
hypotheses which were classifiable as (a) dietetic
imbalance, such as deficiency of fat or excess of
carbohydrate in the food, (b) environment—lack
of exercise and bad hygiene, and (c) specific
infection, were later proved to be of secondary or
no importance in the final development of the
malady.
It is now realized that the true cause of uncom-
plicated rickets is faulty metabolism of calcium
and phosphorus, especially the latter.
The
optimal requirements and correct proportion of
calcium and phosphorus in the diet, the antirachi-
tic vitamin supplied in the food, the action of
sunlight and ultra-violet radiation on the skin,
all these and other minor factors help to improve
the absorption of Ca and P, maintain their normal
level in the blood stream and thus cure or amelio-
rate the symptoms of rickets.
Some interesting cases of rickets among puppies
at this Institute were seen, which did not appa-
rently fit in with the established conception of
the aetiology of the disease, and an account of
these is given with a view to throwing further light
on the subject of causation.
EXPERIMENTAL
Since April 1935 a small kennel of indigenous
dogs has been maintained at this Institute for
experimental purposes. The animals are housed
in blocks of rooms, 8½ × 8 × 10 feet, which open out
on to an enclosure of 14 × 10 × 6½ feet. In each
of these units are accommodated one dog or one
bitch, with pups if any. The locality is isolated
and is exposed to sunlight and fresh air. The
kennels and surroundings are kept very clean,
and the dogs and pups are let out into the en-
closure, weather permitting, from 7-30 A.M.
to 4 P.M. for exercise ; and, when possible, they
are taken out in batches for an hour's walk.
At night, they are locked in the rooms. All the
dogs are fed at 2 P.M. ; the adults on a ration of
½ lb. of cooked meat and 3/4 lb. of wheat flour
cakes. The pups get 4 oz. of cooked meat and
½ lb. wheat flour cakes. In the morning all the
pups get regularly ½ lb. of whole milk, while adults,
especially pregnant and suckling bitches, get a
similar quantity depending upon the available
milk supply. With the above feeding, exercise
and housing arrangements, all the dogs and bitches
are usually quite healthy and in good condition.
Sickness rarely occurs. Normally, all the pups
are quite robust and grow rapidly.
On 17 August 1935, a new bitch—bitch
No. 60—was admitted into the kennel. Unfor-
tunately, nothing is known of her ancestry, as she
was supplied by a dealer in the usual way, but
during the time (upwards of 7 years) she was in
the kennel, she produced 6 litters of pups, some of
which were rickety and some apparently normal.
The breeding and other data concerning this bitch
are given in Table I; similar information for other
animals in the kennel is summarized in Table II.
First litter. The four pups born in February 1936
were apparently normal at birth. After a fort-
night, when they started moving about, a slight
deformity was noticed in the hind limbs, which
gradually increased. So the limbs failed to sup-
port weight, and the pups, when about two months
old, could only drag themselves about. Simul-
taneously, the fore limbs were also affected to a
lesser extent. The long bones were enlarged at the
epiphyses, and the shafts bent outwardly giving a
bow-legged appearance. Later, the limbs turned
or curved outwardly at the elbow. This batch
of pups was issued for experimental purposes, as
there was then a great demand for young pups,
but they succumbed while under experiment.
Second litter. At her second heat, while at the
Institute, she was mated with a different dog,
No. 38, the most ferocious and sturdy dog in the
kennel, as dog No. 74 was found to have a slight
deformity in the right metacarpal region, a defect
of long standing which under the circumstances
was presumed to be a lesion of rickets from which
he might have suffered as a pup. In the other
limbs and in general bodily condition, however,
he was still one of the best dogs in the kennel.
The pups born of this mating developed similar
lesions to those of the previous lot, but observa-
tions could not be continued, as they left the
kennels for experimentation and ultimately
perished.
The blood sera of dogs 38, 74, 1 and bitches
60, 9, 90 were analyzed on 13 June 1938 and the
results are shown in Table III.
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