The aim of this study was to analyse the litter size traits in two genotypes of pig population with black coat: Black Slavonian (BS) and “Nero di Parma” (NP). Data analysis included records from the 1st to 4th parity separately, and all parities (from 1st to 11th) for the following traits: Total Number of Born (TNB), Number of Born Alive (NBA), and Number of Weaned (NW) piglets, collected from 296 BS and 421 NP sows. Litter size traits from 1st to 4th paritywas analysed separately for each breed and ANOVA Repetead Measure test was used to calculate the difference between parities. The analysis of seasonality in all parities was performed using the General Linear Model.Significant differences (P<0.05) between-parity in BS were observed in the 1st and 3rd as well in the 1st and 4th parities for TNB and NW. Only for the NBA difference (P<0.05) was found between 1st and 3rd parities.Differences (P<0.05) in NP pigs were reported between the 1st and 3rd as between 1st and 4th parity for TNB and NBA. First-parity sows for NW shows significant differences (P<0.05) in relation to 2nd, 3rd and 4th parity. In all parities analysed according to the seasons significant differences was recorded between summer and autumn period for TNB (P<0.05) in BS. Difference (P<0.05) was also obtained for NBA between spring and autumn, as well as for summer and autumn season. In all parity analysis in BS pig, the NW (P<0.05) showed differences only between spring and summer period. Season in all parity analysis had a significant impact on litter size traits in NP pig. Differences (P<0.05) was obtained for TNB, NBA and NW among spring-winter, summerwinter and autumn-winter period.Cilj ovog istraživanja bio je analizirati pokazatelje veličine legla u dvije populacije svinja: crne slavonske pasmine svinja (CS) i crne pasmine svinja “Nero di Parma” (NP). Analizirani su pokazatelji veličine legla: ukupan broj oprasenih (UOO), živooprasenih (ŽO) i broj odbijenih odojaka (BOO) od prvog do četvrtog prasenjaza svaku pasminu. Skupnom analizom od prvog do jedanaestog legala prikazani su rezultati UOO, ŽO i BOO po sezoni prasenja. Istraživanjem je bilo obuhvaćeno 296 krmača CS i 421 krmača NP.
Testiranje razlika navedenih pokazatelja od prvog do četvrtog prasenja provedena je analizom varijance s ponovljenim mjerenjima. Podaci skupne analize po sezoni prasenja prikazani su pomoću općeg linearnog modela izračuna. Statističkom obradom podataka utvrđena je značajna razlika (p<0,05) između prvog i trećeg prasenja te prvog i četvrtog prasenja za svojstva UOO i BOO u CS, dok je značajna razlika (p<0,05) u broju ŽO usta-novoljena samo između prvog i trećeg prasenja. Razlika u broju UOO i ŽO bila je značajna (p<0,05) između prvopraskinja u odnosu na treće-i četvrtopraskinje NP. Najmanji BOO u NP zabilježen je u prvopraskinja te su razlike bile značajne (p<0,05) u usporedbi s drugim, trećim i četvrtim prasenjem. Skupnom analizom prasenja utvrđene su značajne razlike (p<0,05) za UOO između ljetne i jesenske sezone te za ŽO između jesenske i proljetne sezone te jesenske i ljetne sezone prasenja (p<0,05). Nadalje, značajna razlika (p<0,05) u BOO zabilježena je između proljetne i ljetne sezone prasenja. Broj UOO, ŽO i BOO u NP tijekom zimske sezone bio je značajno manji (p<0,05) u odnosu na zabilježene vrijednosti tijekom proljetne, ljetne i jesenke sezone prasenja