Optimization of the Performance Test Length for the Sella Italiano Stallion

Figures & data

Figure 1. Length of the testing period in the twelve editions: the mean is 99 days, with a range from 89 days (edition X) to 108 days (edition VII). The edition marked with * refer to a leap year.

Figure 2. Number of scores by day in the twelve editions of the 100-day station test; line is a week moving average; dotted lines show the 33^rd and 78^th day.

Figure 3. Correlation coefficient between EBV of candidate stallions from the complete and the subsets of data: dotted lines show the 33^rd and 78^th day, when the correlation reaches 0.99 for all traits.

Figure 4. Plot of overall indexes calculated from the complete and the validation dataset.

Table 1. The dataset of the candidate stallions that completed the twelve editions of the Sella Italiano performance test.

Edition	Candidate stallions	Training period
	Trainers	Scoring days	Scores
			Character and gaits	Jumping
I (1998/99)	21	9	45	1.084	550
II (1999/2000)	24	8	46	1.059	352
III (2000/01)	32	11	50	1.564	689
IV (2001/02)	23	10	57	1.251	453
V (2002/03)	30	10	57	1.695	565
VI (2003/04)	24	9	57	1.268	439
VII (2004/05)	26	9	60	1.528	516
VIII (2005/06)	27	10	59	1.567	540
IX (2006/07)	28	9	62	1.636	545
X (2007/08)	29	9	60	1.719	577
XI (2008/09)	27	9	57	1.462	562
XII (2009/10)	23	10	68	1.561	503
Total	314	113^*	678^**	17,394	6291

^*Some trainers participated in more than one edition, so that 74 different people were actually involved in training and scoring candidate stallions;

^**character and gaits were scored in every business day; jumping is scored later, and only two days a week, therefore this trait was scored in a total of 243 days.

Table 2. Estimates of variance component and ratios from the complete and reduced dataset.

	Complete dataset				Records from day 33 to day 78
	Phenotypic variance				Phenotypic variance
Character	Gaits	Jumping	Character	Gaits	Jumping
Character	1.126			Character	1.011
Gaits	0.625	1.199		Gaits	0.525	1.108
Jumping	0.646	0.749	1.179	Jumping	0.519	0.521	1.077
	Heritabilities and genetic correlations				Heritabilities and genetic correlations
Character	Gaits	Jumping	Character	Gaits	Jumping
Character	0.39			Character	0.39
Gaits	0.70	0.62		Gaits	0.66	0.62
Jumping	0.76	0.80	0.47	Jumping	0.76	0.77	0.46

^*Some trainers participated in more than one edition, so that 74 different people were actually involved in training and scoring candidate stallions; ^**character and gaits were scored in every business day; jumping is scored later, and only two days a week, therefore this trait was scored in a total of 243 days.