290 



Journal of Agriculture, Victoria. [3 May, 1918. 



number of noughts preceding a unit being counted with the unit. In 

 this way the numbers 1.002,1, 6, 00;» shows four generations from founder 

 1, and, reading backward, we get twenty-first son of sixth son of first 

 son of twentieth son of 1. (The commas are introduced to show the 

 meaning clearly.) 



That the tendency to develop unsoundness is hereditary is admitted. 

 It is hoped that the tables following will confirm this in a more direct 

 and unmistakable manner than has previously been attempted. Fur- 

 ther, an effort will be made to show the influence the dam exerts in intro- 

 ducing unsoundness into sound families, and conversely, soundness into 

 unsound ones. The clearest indication of this is seen in families twenty- 

 eight and sixteen. 



Twenty-eight was not examined; four of his sons were, and found 

 sound at five years of age. Fourteen of his grandsons were also sound 

 — at mature age, in most cases — one of them, 28.033, though certificated 

 at five years, was known to be sound at ten years of age, yet one of his 

 sons, 28.0332, the only unsound member of this family, was affected 

 with sidebone as a three-year old. The dam of this horse was by 16, 

 a horse that was not examined, but which left five badly side-boned 

 horses, and one sound one; the dam of 28.0332 Avas known to be unsound. 

 The sound member of 16 family was from a mare by a son, not recorded, 

 of 9.11 — only two of this horse's sons were examined — one at six years, 

 one at four years of age — and both were sound. As will be seen at a 

 later date this is a sound branch of the family 9. In this case it appears 

 that 9.11 has introduced soundness into family 16, and 16 has intro- 

 duced unsoundness into 28 through the respective dams. 



Whilst this is quite a clear case, the families concerned are of very 

 short line, but similar facts will appear in other families, in which a 

 greater number of progeny is recorded. It is not always possible to trace 

 the dam's breeding for the same reason as that given in the case of 

 sires. One aspect of the question which must not be lost sight of is, that 

 while the presence of sidebone must be accepted as direct evidence of 

 unsoundness, the absence cannot be accepted as evidence of pure sound- 

 ness, unless the animal is of mature age, or unless a sufficient number of 

 his progeny has been examined and found sound to warrant a conclusion 

 being drawn. Further, it is possible that the tendency to develop 

 unsoundness may not be evident in a stallion, yet may be transmitted by 

 him to show in a later generation. 



The tables of families 28 and 16, above referred to, are as follows: — 



FAMILY 28. 



-28.1, not examined- 



28 •2, not examined^ 



23 '3, not examined 



28 •4, not examined 



28 'a, sound, 5 



28 '6, not examined 



28 •? sound, 5 



28 -8, sound, 5 — 



28 "9, not examined — ■ 



28 -01, not examined 



28 '02, not examined- 



28 '03, not examined . — 



28 -04, sound, 5 



28 •05, not examined- 



-28-11, sound, 5 

 28-12, sound, 5 

 -28 -21, sound, 4 

 -28-31, sound, 5 

 -28 -41, sound, 4 



-28 -61, sound, 4 



-28-81, sound, 3 

 -28-91, sound, 4 

 -28-011, sound, ;! 

 -28-021, sound, 4 

 -28 -031, sound. 5- 



28 -032, sound, 5 

 28 033, sound, 5- 



-28-051, sound, 4 



-28-0312, sound, 2 

 28-0311, sound, 2 



-28 -0331, sound, 3 

 28 -0332, SIDEBONE, 3 



