Z namenom proučevanja možnosti vključitve klavnih lastnosti v napoved plemenske vrednosti pri prašičih smo ocenili komponente variance za lastnosti, ki se za ocenitev odstotka mesa v prašičjem trupu ...merijo na klavni liniji ter za lastnosti šunke. V analizo smo zajeli 2167 pitancev (1046 kastratov in 1121 svinjk) z znanim poreklom. Pitanci so bili skupinsko vhlevljeni s krmljenjem po volji v proizvodnih razmerah na farmi Nemščak. Zaklani so bili med aprilom 1999 in decembrom 2000. Komponente variance smo ocenili z enolastnostnimi modeli po metodi omejene največje zanesljivosti (REML). V sistematski del modelov smo vključili vpliv spola, genotipa in sezone (leto-mesec) kot vplive z nivoji ter maso toplih polovic ali starost ob zakolu kot linearni regresiji, v naključni del pa vpliv živali. Ocene heritabilitet so bile srednje do visoke; za maso toplih polovic (0,32), za meritev M (0,41), ki je najkrajša razdalja med prednjim koncem m. gluteus medius in zgornjim robom hrbteničnega kanala, za meritev S (0,45), ki je najtanjša debelina podkožnega maščobnega tkiva s kožo nad m. gluteus medius, za odstotek mesa (0,46), za maso mesa (0,38), za maso šunke (0,32), za maso kože s podkožno maščobo šunke (0,47), za maso mesa in kosti šunke (0,41), ter dnevni prirast mase toplih polovic (0,32) in dnevni prirast mase mesa (0,38). Poleg heritabilitet so bile velike tudi aditivne genetske variance. Za vključitev v selekcijski program bi na podlagi ocen predlagali odstotek mesa in maso kože s podkožno maščobo šunke.
The influence of the immunocastration (immunisation against GnRH) on pig performance (growth, carcass and meat quality traits) was investigated in two parallel experiments (on two farms) with two ...crossbreeds – G1 (50% Duroc) and G2 (50% Pietrain). Within the crossbreed, the pigs were assigned to three experimental groups; entire males (EM, n=49), immunocastrates (IC, n=45) and surgical castrates (SC, n=45). Those assigned to IC group were vaccinated at the age of 12 and 19 weeks. Pigs were individually housed, their feed intake (ad libitum) and weight (at 12, 19 and 24 weeks) were recorded. At the age of 24 weeks, the pigs were slaughtered and their carcass and meat quality traits were assessed. We hypothesized that treatment response could have been different in two crossbreeds. However the interaction was insignificant, thus the treatment effect is presented on pooled results for both crossbreeds. Until the revaccination, IC were similar to EM pigs, thereafter they exhibited an increase in feed intake and growth rate. Overall, they presented an advantage in growth rate and feed efficiency as compared to SC. They also exhibited better carcass properties as SC without any major effect on meat quality. The present study provides the initial information on the immunocastration effect in Slovenian herds that should further be supported by testing it in usual rearing conditions and group housing.
Cilj rada bio je odrediti djelovanje dvaju različitih acidifikanata na rast praščića u razdoblju od odbica do postizanja tjelesne mase od 30 kg. U istraživanje je bilo uključeno 336 svinja ...podijeljenih u dvije jednake skupine (Fra Acid, n = 168, Acidad Dry K n = 163). Na temelju tjelesne mase pri odbiću praščići su podijeljeni u "laku" (L = 6 kg) i "tešku" (H = 8 kg) skupinu. U obrocima praščića upotrijebljena su dva acidifikanta različitog sadržaja organske kiseline. U hranu je dodavan Fra Acid u koncentraciji od 0,65, 0,60 i 0,40%. Drugi dodatak, Acidad Dry K, dodavan je u koncentracijama od 0,35, 0,30 i 0,20%. Praščići su pojedinačno vagani pri odbiću, zatim 23. dana starosti i opet svaki puta kad je promijenjena hrana (35., 49. i 82. dan starosti). Pokusne skupine nisu se značajno razlikovale u tjelesnoj masi za vrijeme pokusa. Praščići s Acidad Dry K postigli su veće dnevne priraste od praščića hranjenih s Fra Acidom, ali povezanost nije bila statistički značajna. "Teški" praščići u tretmanu s Acidad Dry K imali su značajno više dnevne priraste u razdoblju od 49. do 82. dana starosti u odnosu na one u Fra Acid tretmanu (567± 80 g, 507± 140 g, p = 0.04).
