ijOQ Rickets, Bone Softening, and Paralysis 
quality and apportioned according to the breeding state they 
are in ; remember that the foetus as well as the cow is to be 
kept in a growing healthy condition. Avoid the practice of 
giving inferior and refuse food to in-calf cows. Be very par- 
ticular respecting the purity of the water supply ; neglect of 
this is a fruitful cause of abortion. See to general sanitary 
arrangements, ventilation, pure air, and good drainage ; use 
disinfectants freely. In the fields, keep a sharp look out for 
decomposing putrid matter, which effectually destroy. Exercise 
is most important ; even in winter, cows should be let out for 
a short time each day. Before service, be sure that the generative 
organs of both animals are healthy. Where possible, split up 
the herd into small lots, cows with bull calves, cows with heifer 
calves, cows and heifers to serve, cows and heifers settled in-calf, 
and doubtful breeders by themselves, which do not serve with 
a valuable bull, or unless they are regular. 
Attention to these details will do much to prevent and modify 
outbreaks of abortion ; but in connection with this subject there 
is another important deep-seated and common enemy to fight, 
and to which I have already directed attention, namely, the 
insidious pest — tuberculosis. This disease, known in some 
districts as consumption, wasting, clyre, &c., is pre-eminently 
hereditary, and is sure, sooner or later, to develop itself in some 
form. Animals and families in which it is known to exist 
should therefore be avoided. More attention should be paid 
to nature's law, " the survival of the fittest," and only sound 
vigorous animals bred from. Constitution and breeding records 
should be as carefully enquired into as pedigree, for they, like 
other peculiarities, are transmittable, and may be as surely 
cultivated as any other characteristic of a family. 
XXI. — Richets, Bone Softening, and Paralysis in Lamls and 
Young Sheep. By VV. Robertson, Principal of the Royal 
Veterinary College. 
Amongst lambs and young sheep, during the first year of their 
life, there is in certain districts of Great Britain, and on 
particular soils under ascertained conditions of cultivation, 
a very serious form of disturbed nutrition of bone, which, 
although well enough known, has not yet received the attention 
it seems to deserve. Under what I am disposed to regard 
as imperfect or mal-development and nutrition of bone-tissue 
in these animals, 1 would now desire to speak of what have 
hitherto been regarded as at least two distinct diseases : 
