Celozivotni uzitkovost dlouhovekych prasnic ve vztahu k veku pri prvnim zabreznuti.
1990
Pavlik J. | Kolar M.
Investigation was made of 170 sows of the Prestice Black Pied breed where in each sow reproduction characters were checked up in the first to the eighth litter. These sows were classified according to the age of their conception for the first litter. Beside the evaluation of the observed parameters by means of common mathematical and statistical methods, the method of minimum squares of the curve showing the changes in relation to the age of conception of sows for their first litter was combined with the values obtained in particular groups. For example, in the number of surviving piglets this curve is characterized by the following equation: y = 8.2 + 0.0100x - 0.000018x2. Based on the evaluation of all the parameters of reproduction characters and in view of the long-term use of sows in selective breeding, the optimum age for the first conception of sow could be estimated at 8 to 8.5 months. The unsuitable ages are less than 7.5 months and more than 9.5 months.
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