Influence of birth month on age at first start and racing performance in young trotters

Saastamoinen, M.T.; Ojala, M.J.

Acta Agriculturae Scandinavica 41(4): 437-446


Race records for 2 through 5-year-old Finnish Standardbred trotters (n = 3140) and for 3 through 6-year-old Finnhorse trotter (n = 2634) were used to estimate the influence of birth-month on age at first state and racing performance. Standardbred trotters born from January to March were about half a year younger at first start than their contemporaries born from August to October. The effect of birth-month on racing performance of horses was more pronounced in Standardbred trotters than in Finnhorse trotters. The influence of birth-month was expressed most clearly in three-year-old Standardbred trotters; horses born from January to March were faster (p < 0.001), had greater earnings (p < 0.01) and a larger number of both first placings (p < 0.05) and first-to-third placings (p < 0.001) than their racemates born later. In regard to the performance over the whole career in Standardbred trotters, the most advantageous months of birth were from January to May. In Finnhorses the most advantageous birth-months seemed to be March, April, May and June (non-significant). The poorest performance in both breeds was observed for horses born in late summer or in the fall.