Reproductive indicators and development of lambs until weaning in Svrljig Pramenka sheep

Abstract

As regards a race structure of sheep in Serbia a domestic tuft sheep, Pramenka, is still a dominant one (about 80%). There is a great number of Pramenka breed types, its crossbreds with different breeds, as well as the crossbreds of Pramenka with improved breeds. Improving of domestic tuft sheep, in the last two decades, was directed mostly towards improving the production of lamb meat, where württemberg and Ile de France were most often improving breeds used. The improvement of sheep in 50-ties and 60-ties of the last century was carried out with the aim of improving all three productions (meat, milk, wool), while one of the more important and organised projects was "merinozation", ie., improving by Merino sheep. In spite of all controlled and random breeding activities realized in the process of improving the sheep stock in Serbia, Pramenka is still the most important sheep in a breed structure. A Svrljig type (second in importance, after Sjenica type) is a particularly distin gushed one. Svrljig breed is significant both for the size of its population and areas of its raising, as well as traditionaly recognizable products made from the sheep of this breed (svrljiski cheese, homoljsko lamb). A format, body weight of adult animals of Svrljig sheep, together with their well-known milk yield, are good prerequisites for the production of lamb meat. Sheep fertility is a major factor on which the yield of meat per sheep depends, being restricted by both genetic predispositions (a breed trait), and paragenetic factors (rearing conditions, season, age, etc.). It is well-known that lambs body weight gain is the most intensive in the first three months after birth so exactly in this period the optimal conditions must be provided in order that genetic potential in meat production should be completely expressed. In a population of 393 lambed sheep of Svrljig Pramenka sheep, raised on 11 private farms, a fertility of sheep and body weight gain of lambs from birth till weaning was analyzed. A body weight of lambs at birth ranged from 2,3 to 5,5 kg, body weight on 30. day was 7,5 kg to 15 kg, and body weight at weaning from 26 to 36 kg. Lambs breed and sex had a significant effect on studied indicators of lamb development.

U radu su prikazani rezultati koji se odnose na plodnost ovaca i razvoj jagnjadi svrljiške pramenke, a koji su utvrđeni u populaciji od 393 ojagnjene ovce, gajene na ukupno 11 privatnih gazdinstava. Plodnost ovaca prosečno je iznosila 111,45%, sa variranjem po gazdinstvima od 106,06 do 119,35%. Praćen je razoj jagnjadi od rođenja do odbijanja. Masa jagnjadi na rođenju kretala se od 2,3 do 5,5 kg, masa sa 30 dana 7,5 kg do 15 kg, a masa pri odbijanju 26 do 36 kg. Tip jagnjenja i različiti odgajivački uslovi na gazdinstvima visokoznačajno (p lt 0,01) su uticali na masu jagnjadi pri rođenju, sa 30 dana i pri odbijanju. Pol jagnjadi kod jedinaca visoko-značajno (p lt 0,01) je uticao na telesnu masu u sva tri kontrolna merenja, dok kod blizanaca po polovima razlike u telesnoj masi sa 30 dana i pri odbijanju nisu bile statistički značajne (p>0,01).