Estimation of longevity of sows in connection with breeding

Abstract

During selection of breeding sows the usefiul life period as well as lifetime production among a number of important value-measuring features do not play a proper role in proportion with their importance. The above value-measuring feature marks not only the reproduction, milk productivity’, piglet growing ability of breeding animals, but contains information in connection with reproduction. Furthermore, longevity refers to the constitution of sows, that is, enables us to identify the genotypes being able to reach high maternal production without health problem. Moreover, sow’s can get acclimatised to the microclimatic environment, feeding, keeping, caring etc. We have collected data in our nucleus herd, which is directed by our department. We investigated data of 531 sows involved in breeding from 1991 to 1998. We did not group sews in the usual form but sows, which were sorted out after the subsequent farrowings were put into the appropriate groups. Besides, the currently used reproduction parameters the two longevity-indicating parameters worked out by our department were also applied in the present investigation. The number of life-days of sows per one piglet was the most unfavourable among sows culled after the first farrowing, then this parameter showed an improving trend till the sixth farrowing. The other parameter is the piglet gain per one sow-life-day, which rises till the seventh farrowing and after this, it remains on approximately the same level till the eleventh farrowing. The used reproduction index "SzFTV" is improving till the eighth farrowing, however, this index does not mark longevity. You can see the lessening variability of the three investigated parameters in the case of sows culled after the successive farrowings.