The aim of the study was to compare carcass composition and meat quality of i) Pekin ducks of French origin (P9), ii) crosses of wild mallard and Pekin duck (K2), and iii) crosses of Khaki Campbell drakes and Orpington Fauve ducks (KhO1). Twenty carcasses from 110-week-old ducks of each genetic group were used. Carcass weight of P9 was significantly higher than that of K2 and KhO1. Carcasses of K2 ducks had a significantly lower percentage of neck and leg muscles and giblet weight compared with P9 and KhO1 ducks, while carcasses of KhO1 ducks had a significantly higher percentage of wing meat compared with K2 and P9, and a significantly lower percentage of breast muscles compared with P9 ducks. Breast and leg muscles of P9 contained significantly more water than those of K2 and KhO1, and the breast muscles of P9 ducks had more protein and less fat than those of KhO1 birds. The leg muscles of KhO1 contained significantly more protein, and those of K2 had significantly more fat than the other duck groups. Breast muscles of P9 and KhO1 ducks had significantly more collagen but had less in leg muscles compared with K2. Breast fillets from P9 ducks showed higher L*, a*, and b* colour values and shear force than K2 and KhO1 ducks. Keywords: carcass composition, conservation flocks, meat quality, spent duck

The aim of the paper was to investigate the impact of feeding pigs with different levels of conjugated linoleic acid or sunflower oil on fatty acid profile of Longissimus dorsi muscle. The subjects of research were 60 crossbred gilts divided into 6 groups, fed with different levels of conjugated linoleic acid (CLA) or sunflower oil (SFO) (0.5; 1.0 and 2.0 %, respectively). All fatteners were kept and fed under standardized conditions. Animals were slaughtered at 95 kg of body weight. Fatty acid profile was determined in samples of Longissimus dorsi muscle from each animal. Gas chromatography was used (in the research). The significance of differences between groups was verified by Duncan's test. In the present study the addition of conjugated linoleic acid or sunflower oil did not impact the composition and amounts of saturated or unsaturated fatty acids in Longissimus dorsi muscle. Keywords

Backfat Fatty Acid Profile of Crossbred Pigs Fed a Diet Supplemented with Conjugated Linoleic acid or Sunflower OilThe aim of the study was to investigate the impact of feeding pigs with different levels of conjugated linoleic acid (CLA) or sunflower oil (SFO) on the backfat fatty acid profile. The subjects of research were 60 crossbred gilts divided into 6 groups, which were fed different levels of conjugated linoleic acid or sunflower oil (0.5, 1.0 and 2.0%, respectively). All fatteners were kept and fed under standardized conditions. Animals were slaughtered at 95 kg of body weight. Fatty acid profile was determined in samples of backfat from each animal using gas chromatography. The significance of differences between groups was verified by Duncan's test. In the present study, a beneficial effect of adding CLA was that it reduced saturated fatty acids and increased unsaturated fatty acids in the adipose tissue (backfat) of pigs as compared to fatteners receiving SFO. The amount of monounsaturated fatty acids in the backfat decreased with increasing amounts of CLA or SFO. Modifying the fatty acid profile of pig backfat through addition of CLA or SFO would be beneficial to the health of consumers because relatively large amounts of fat pork, including backfat, are added to the sausages.

The aim of presented paper was analysis of the performance test results of young pure breed boars coming from The Bydgoszcz Breeding Region (located in Poland in Kujawy-Pomorze Province). The research covered the results concerning 4190 young boars of following breeds: Polish Large White, Polish Landrace, Hampshire, Duroc and Pietrain. Young pure breed boars were performance tested in 2009 and 2010 in The Bydgoszcz Breeding Region according to the actual methodology. Among young pure breed boars performance tested in The Bydgoszcz Breeding Region in tested years animals of Hampshire breed had the higher growth rate. The pigs of Pietrain breed had the highest meat content. Regarding to the most important parameter of performance test, i.e. selection index in analyzed years 2009 and 2010 the best results had young boars of Hampshire then Pietrain, Duroc, PLW and PL.Keywords: daily gain of body weight, meat content, performance test, selection index, young pure breed boars Abstrakt Celem prezentowanej pracy była analiza wyników oceny przyŜyciowej knurków czysto rasowych pochodzących z bydgoskiego okręgu hodowlanego (zlokalizowanego w Polsce, w woj. kujawsko-pomorskim). Badaniami objęto wyniki dotyczące 4190 knurków ras: wielkiej białej polskiej, polskiej białej zwisłouchej, hampshire, duroc i pietrain. Knurki zostały poddane ocenie przyŜyciowej w 2009 i 2010 r. w bydgoskim okręgu hodowlanym według aktualnej metodyki. Spośród knurków czysto rasowych ocenionych przyŜyciowo w bydgoskim okręgu hodowlanym w badanych latach zwierzęta rasy hampshire odznaczały się największym tempem wzrostu. Świnie rasy pietrain charakteryzowały się największą mięsnością. Pod względem najwaŜniejszego parametru oceny przyŜyciowej, tj. indeksu selekcyjnego w analizowanych latach 2009 i 2010 najlepsze wyniki uzyskały knurki rasy hampshire, następnie pietrain, duroc, wbp i pbz. 12Journal of Central European Agriculture, 2016, 17(1), p.12-24 DOI: 10.5513/JCEA01/17.1.1662Słowa kluczowe: indeks selekcyjny, knurki czysto rasowe, mięsność, ocena przyŜyciowa, przyrost dobowy masy ciała Streszczenie szczegółowe Znaczący postęp wartości hodowlanej trzody chlewnej w zakresie uŜytkowości tucznej i rzeźnej nastąpił na skutek prac hodowlanych prowadzonych na podstawie oceny przyŜyciowej. Wyniki tej oceny są jednym z podstawowych kryteriów w pracach selekcyjnych nad trzodą chlewną przy wyborze zwierząt do stad hodowlanych i produkcyjnych. Bydgoski okręg hodowlany zlokalizowany jest w woj. kujawsko-pomorskim i w produkcji świń zajmuje czołowe miejsce w Polsce, a produkowane na jego terenie knurki i loszki oddziałują na poziom uŜytkowości tego gatunku zwierząt w kraju.