10 May, 1910.] Hereditary Viisoiiudness tn Horses. 333 



B. — Concerning Hereditary Unsoundnesses. — 



1. As regards Sidehonc that — 



(a) Ponies do not develop sidebone as a form of hereditary 

 unsoundness ; 



{h) In light horses sidelx)ne is so rare that it may be con- 

 sidered negligible ; 



(c) This form of unsoundness is i)racticallv confined to 

 draught horses, and is the most common of all forms 

 of hereditary unsoundness in draught horses, and 

 further tha,t its incidence in draught horses is practi- 

 cally six and a half times greater than that of any 

 other hereditary unsoundness, either in draught horses 

 or in any other breeH 



2. As regards Ringbone that — 



{a) In ponies and light horses the occurrence of ringbon 



is rare ; 

 {b) In draught horses ringbone is, next to sidebone, the 



most common form of hereditary unsoundness. 



3. As regards Bone Spavin — that this form of unsoundness — 



{a) Is practically confined to light horses. 



{b) Is the most common form of hereditary unsoundness in 



light horses. 

 {c) Is so rare in ponifs and in draught horses as to te 



regarded as practicall}' negligible. 



4. As regards C7(rb that — 



{a) Curb may be regarded as being an hereditary unsoundness 



in light horses and ponies only ; 

 {b) Curb is the most common form of hereditary unsoundness 



in ponies ; 

 {c) Curb is rare in draught horses and negligible as a form 



of hereditary unsoundness. 



5. As regards Bog Spavin, Thoroughpin, Cataract, and Roaring, 



the figures are insufficient for any reliable conclusions to te 

 drawn. 



Age-period of Development of Unsoundness. 

 No horses under two years old have been examined. Next to aged 

 horses ( six years and over) the age at which the greatest number has been 

 submitted is three years. The excess of three-year-olds over four- and 

 live-vear-olds, is accounted for bv the fact that during the second and 

 third years there was the influx of an additional crop of colts of this 

 age entering on a stallion career. The figures in some cases {e.g. ponies), 

 and as regards the more uncommon unsoundnesses, are scarcely sufficient 

 from which to generalize as to the age-period of development of unsound- 

 ness. As regards the more common unsoundnesses, however, it will -be 

 seen from the tables given below, that the percentage proportion of unsound- 

 ness is least in two- and three-year-olds and increases each year until the 

 age of maturity, at which age-period (six years and over) the greatest 

 percentage of unsoundness is found in all breeds. Indeed, it is quite 

 likely that the proportion of unsoundness in aged liorses is even greater 

 than is shown in the tables, for the reason that a large number of horses 

 past a showing age, and which were known bv their owners to be unsound, 

 have not been submitted for examination. 



