Factors Affecting Age at Onset of Breaking, Training, Qualifying and First Start in Finnish Trotters

Abstract

An inquiry study was carried out to evaluate the effect of some environmental factors on ages at breaking, at the beginning of training, at qualifying and at first start. Also the heritability estimates for, as well as the phenotypic correlations among the ages were calculated. Furthermore, the main reasons for late beginning and non-starting were queried. The numbers of acceptable responses were 796 for Standardbred trotters and 857 for Finnhorses. The coefficient of variation in ages was quite large ranging approximately between 20 and 37%. Males tended to be younger than females when starting breaking, training and competition. Horses broken and trained by professional trainers came to breaking and training and started racing earlier than other horses. For Standardbred trotters, started horses were younger at breaking and at the beginning of training and at qualifying than those never started. Heritability (h ²) estimates for ages ranged from 0.06±0.09 to 0.20±0.13 in Standardbred trotters, and from 0.00±0.11 to 0.25±0.12 in Finnhorses. The highest h ²-estimates were observed for age at first start in both breeds, and for the age at breaking in Finnhorses. The ages were positively correlated with each other.

Key Words:

• trotting
• racehorse
• environmental factors
• heritability