Suomalaisen hevosen vetovoiman kehittämisestä

Abstract

The development of the horses’ pulling power by breeding is disturbed by many factors which render it difficult to substantiate. At the time of registration for, the pedigreebook, the pulling test done by the dynamometer does not present a right picture of every stallions pulling power, as all are not sufficiently well trained for the test. Also the experience of pulling is often slight owing to the lack of work, eventhough the war has improved the situation in this respect. Furthermore faults in caring for and feeding the horse may hinder producing the horses’ full pulling propensity. Besides these different circumstances may effect the results of test performed at various times of the year. Especially the average level of the results in the spring show is erronecously high owing to the test car s tyres slipping on account of the wet ground. The affect of all the above-mentioned inaccuracies can be lessened by using the experimental technique, and the great rise in the experimental results after 1940 is foremost to be put to the merit of the stallions being better accustomed to work, showing that the development has quickly led to even more dependable results. But even if all these experimental faults in technique could be removed the pulling ability of the stallion in the pulling test does still not show its tractive ability because it is the combined results of power and character. The dividing of horses into stepgrades shows that the characteristically deficient horses weed out together with the inexperienced already in the exercise- or walking route or in the first steps. This is confirmed by the manner of weeding out, because horses belonging to the lower stepgrades are not able to start their pull at all; when insted strenght fails those which have reached the higher steps while on the traction stretch with their load. In investigating the inherited pulling power one has, therefore, taken into account from each age group only the stallions who have pulled at least 35 % of their liveweight, as in this way one has been able to weed ont the lower stepgrades’ characteristiccally deficient and untrained horses. The correlation obtained from sires and sons by this procedure is +0.29 ±O.lO. Now the mares’ different pulling reliability was not at all taken into account. In order that the mares dissimilar influence on results could be made the lowest possible, the correlation has also been calculated only from material comprising sons whose dams’ pulling reliability has been valued at 6 points. The correlation then obtained is +0.33±0.11. The final result is harmfully effected by the fact that the correlation is nearest dependent on the stallions who have plenty of offspring. Owing to this, the results have been calculated so that the average of each son has been reckoned and that the correlation between the sires’ and sons’ average. Thus one obtains in the whole material of the sires’ and sons’ correlation +0.37 ±0.15, and from the material comprising sons of 6 point dames +0.46 ±0.15. The sons have been at an average 0.32 steps better than their sires, which foremost is due to them being better trained for the pull. In the pulling results of the sons one can however also notice the influence from the dams, because the sons of 6 point dams have at an average been 0.78 steps better than their sires, and the sons of 5 point dams exactly equal with their sires, and the sons of 0-4 point dams 0.15 steps poorer than their sires. The comparison of the average of all the stallions shows that the sons of the best stallions have most obviously exceeded the midlevel and from the point of view of development of pulling power the best results have been gained when more powerful stallions have been used in breeding with dams most reliable in pulling. In order to gain even better results in the development of horses’ pulling power, the excercising for test should be made even more effective than previously. To lessen the technical test faults the spring shows should be given up and even in summer when the ground is wet, the slipping of car tyres should be prevented by snow-chains. The testing of dams’ pulling power should be developed similarly to that of the stallions. The pedigree book demands should follow the rapid progress which has been noticed in recent years in the pulling tests thanks to better training.