Phenotypic variability of fertility traits of pure breed sows in first three farrowings

Abstract

Investigation of the phenotypic variability of fertility traits was performed on Swedish Landrace sows (926 sows) deriving from single herd in Serbia. Data was processed by method of least squares (Harvey, 1990), and following fixed factors were included into the model: sire, season, litter genotype and order of farrowing, as well as regression effect of age at first farrowing, duration of lactation and number of reared (raised) piglets per litter. Traits of litter size varied (P (lt) 0.01) under the influence of sire and order of parities (first two parities). Number of still born as well as reared piglets per litter depended on the litter genotype (P (lt) 0.01). Year and season had no effect on variation of litter size traits except LWW (first two and three parities). Age of sows at first farrowing demonstrated linear effect (P (lt) 0.01) on size of their litter at farrowing (first three parities). Litter size and weight at weaning were under regression effect of lactation duration as well as corrected litter size (CLS) or number of weaned piglets (NW).

Ispitivanje fenotipske varijabilnosti osobina plodnosti krmača rase švedski landras sprovedeno je u jednom zapatu svinja u Srbiji. Podaci su analizirani primenom različitih modela metoda najmanjih kvadrata (Harvey, 1990), u koje su bili uključeni sledeći fiksni uticaji: otac, godina, sezona, genotip legla i redosled prašenja, kao i regresijski uticaji uzrasta pri prvom prašenju, trajanja laktacije i broja gajene prasadi u leglu. Istraživanjem je bilo obuhvaćeno 926 krmača i njihova 926 prva, 1598 prva dva i 2115 prva tri prašenja. Prosečna ispoljenost trajanja perioda od zalučenja do estrusa i oplodnje (W-E i W-C), broja živorođene (NBA), ukupnorođene (TNB), mrtvoroĐene (NSB) i odgajene prasadi (NW) kao i mase legla pri zalučenju (LWW) u prvom, prva dva i prva tri prašenja je bila: 9.77, 8.51, 7.80; 23.77, 20.98, 19.49; 8.31, 8.91, 9.19; 8.87, 9.46, 9.78; 0.56, 0.54, 0.51; 7.57, 8.04, 8.24 i 52.43, 58.18, 61.10, respektivno. Osobine veličine legla su varirale (P (lt) 0.01) pod uticajem oca i redosleda prašenja (prva dva prašenja). Broj mrtvorođene kao i odgajene prasadi u leglu zavisili su od genotipa legla (P (lt) 0.01). Godina i sezona nisu uticale na variranje osobina veličine legla osim na LWW (prva dva i tri prašenja). Uzrast krmača pri prvom prašenju ispoljio je linearan uticaj (P (lt) 0.01) na veličinu njihovih legala pri prašenju (prva tri prašenja). Veličina i masa legla pri zaluženju su bili pod regresijskim uticajem trajanja laktacije, korigovane veličine legla (CLS) ili broja odgajene prasadi (NW).