June, 1950]
F.
C.
MINETT
75
dying from such ailments as 'diarrhoea', 'enteritis', 'anaemia', and 'debility',
are included, even if worm parasites were not reported as occurring in them, if there
is evidence of the widespread existence of parasitism on the farm. Where there
is no such evidence, animals dying below six months of age are included in group 1.
Admittedly, in making such allocations mistakes are inevitable owing to defects
in diagnosis, but they may not be important on the whole and some arbitrary divi-
sion has to be made. It appears from the Tables II and V that in sheep, excluding
20 per cent in adults, the age of which is not known, parasitic attack is most fatal
in sheep below the age of two years and is especially heavy between the ages of
6 to 12 months. There is no great variation in this respect on the individual farms,
but at Bhamburda rather more than half the deaths under this category occurred
in four to five year old animals. This is exceptional and from the reports of this
station it seems more likely that malnutrition resulting from climatic stress is the
cause rather than parasitism. This, of course, may also be true of some other farms.
With goats also, at Etah, most of the deaths from parasitic attack occur before
the age of two years.
Group 3. It contains all cases of six months and over in which lung affections
were considered responsible for death. The total for sheep, excluding Banihal,
is only 153. Banihal is excluded since there almost all the lung affections occurred
in lambs from 3 to 12 months of age, suggesting that lung disease was not a primary
cause of death. The reason for the general age limitation to over six months is
because conditions labelled pneumonia in very young animals are quite likely not
pneumonia in the true sense, but merely pulmonary congestion or oedema arising
from weakness or other cause. Since, however, pneumonia may be the immediate
cause of death in old animals, ones over six years of age are included in this group.
If then Banihal is excluded, the heaviest incidence of pneumonia in sheep falls in
the six months to two years age groups, though the figures are too small for men-
tioning particular farms. Much the same is true of goats.
Group 4. It contains animals dying at six years and over from no easily apparent
cause. This includes cases labelled 'debility'. In one-third of the cases in sheep,
the age of the 'old' animals is not stated, while there are very few cases attaining
nine or ten years.
Group 5. (Sheep only). It contains miscellaneous diseases or other factors con-
tributing to death, which deserve mention owing to their effect on the mortality
rate of individual farms. Included are sheep-pox at four farms, a disease at Quetta
designated 'obscure' and about the most serious complaint at this station, tympany,
rinderpest, 'encephalo-myelitis', deaths from wild animal attack, at Banihal 'rains'
which were on one occasion responsible for severe loss, and finally deaths which
are frankly described as of unknown origin.
With sheep-pox, the heaviest mortality falls in two age groups, birth to six
months and two to three years. The disease is usually said to be most fatal in lambs,
but this apparently is not the case at Garudapalya. At Banihal, the effect of the
heavy rains was greatest in lambs, as might be expected. The 'obscure disease'
at Quetta chiefly affected adults from one year upwards. Wild animal attack
caused more severe losses in lambs than in adults, whereas losses from rinderpest