138
Some Observations on Rickets in Pups
These results may be compared with normal
values for serum Ca and P given by Dukes [1937]
and by Meysenbug and M'Cann [1921]. The
former gives 9.0—11.0 mg. Ca and 2.2—4.0 mg.
inorganic P per 100 c.c. serum, while the latter
authors in four normal dogs found serum Ca to be
10.2, 10.3, 10.6 and 10.7 mg. respectively per
100 c.c. serum.
Third litter. At the third heat, she was again
mated with No. 38, the best dog available. Of
the five pups produced, one died within a week
without apparent cause. Of the other four, one
was found to be quite normal and of good size.
The other three developed symptoms of rickets
within three weeks of birth. Close observation
was maintained and the symptoms developed
rapidly. These symptoms were similar to those
already described and, in addition, the costochon-
dral junctions were enlarged as in the well-known
condition of 'rickety rosary', while below the
metacarpal joints the limbs were curved outwardly.
The pups, while moving, dragged their hinder
parts, so that the parts were denuded of hair and
roughened, while the forelimbs rested on the
metacarpal joints. The foreheads appeared to
be wider than normal and the bone more convex, as
compared with the other pups. The cheeks,
though not covered with good muscle, seemed
quite rounded and full. The teeth were apparent-
ly normal in colour and texture. With a fort-
nightly dose of castor oil, these pups developed
no further symptoms. Their appetite through-
out remained good.
Further medicinal treatment was undertaken
when the pups were 2½ months old, by which time
the disease was well established. One of the
three pups was kept as a control and the other two
were given a dessert-spoonful of cod liver oil daily
in their milk. The control pup (a), which was get-
ting the routine ration only, died on 15 April 1938,
and there were extensive signs of rickets at autop-
sy. The femur and ribs of this pup and of a normal
pup were analyzed, and the results, along with
those obtained by Mellanby [1921] of rachitic
pups, are given in Table IV.
These figures seem to be low enough to indicate
advanced rickets. Mellanby [1921] considered
his cases as having 'bad rickets '. Steenbock and
coworkers [1923, 1924, 1925] also considered the
results of bone analyses to be reliable criteria for
judging the severity of rachitic conditions. In an
claborate study carried out by Adams and
McCollum [1928], it was found that the percent-
age of ash decreases as the severity of rickets
increases. Similar observations have been made
by McCrudden [1910], Loll [1923] and Hawk and
Bergeim [1931] in human rickets and osteo-
malacia.
Of the three now surviving pups, one was normal
in every respect from the beginning and the other
two were rickety. One of the two pups under
treatment (pup b) improved rapidly both in
general condition and in its skeleton. The bones
straightened, the limbs could support the body,
and the epiphyseal swellings decreased to very
nearly normal. The other pup (c), in spite of the
treatment with cod liver oil, did not show any
change. The joints became very large. The
hinder parts were always dragged, the forelimbs
bent, the thorax sunk irregularly, the right
humerus was bent on itself forming a hook, the
general condition gradually became worse, the
appetite was capricious and the animal developed
intermittent diarrhoea and passed stools mixed
with undigested cod liver oil. From 17 May 1938,
the usual ration plus cod liver oil was supplemented
with a little calcium carbonate and the limbs
were massaged with cod liver oil. With this
additional treatment, good results were obtained.
The symptoms of indigestion disappeared first,
the animal picked up condition, the long bones
lost their curved appearance and the enlargement
of the joints decreased. Within a month of this
enhanced treatment, the pup began to walk with a
firm gait on all its limbs, except the right fore.
The humerus of this limb was still bent at the
middle, but with massage and the dietetic sup-
plement this bone was also straightening.
Litter 4. During this pregnancy and the suck-
ling period, i.e. from 23-9-39 to 24-1-40, the bitch
was given iv drachms cod liver oil daily, and this
apparently was responsible for the enduring well-
being of the three pups born. Of these three pups,
two were used for other experiments and one
remains. This one (bitch No. 179) when 19
months old gave birth
to three pups
of which two survived and remained healthy.
These two survivors have produced one litter
each, 7 pups in all and these—now two months
old—are growing normally.
Litter 5. Of the two young, one remained
normal and one developed mild rickets. During
this pregnancy, as in the earlier ones, the bitch
was not given cod liver oil.
Litter 6. Of the four young, one died imme-
diately after birth, one remained apparently
normal, while the other two developed severe
rickets of the fore limbs. Of these two, one died
later and the second is surviving, with greatly
deformed limbs. It is proposed, if possible, to
use this animal for further matings with healthy
bitches.
DISCUSSION
In considering the aetiology of rickets in these
litters of puppies from bitch No. 60, the following
factors may be taken into account.