Cytogenetic investigation in two endangered pig breeds raised in Southern-Italy: clinical and environmental aspects

Representative groups of animals of two endangered local pig breeds (Casertana and Nero Siciliano,both with black skin and raised in Southern-Italy) were cytogenetically investigated and comparedto check for the presence of chromosomal abnormalities and to test their chromosome stability by Sister Chromatid Exchange (SCE) test, in their normal breeding conditions. Forty-two Casertana pigs (22 males and 20 females, raised in 3 farms) and 39 Nero Siciliano pigs (19 males and 20 female, raised in 3 farms) were investigated. All animals showed normal CBA- and RBA-banded karyotypes (2n=38), except for two Nero Siciliano boars (both from the same farm) which showed US 2n=37 being heterozygous carrier of rob(15;17). The translocation was confirmed by FISH-mapping with specific BAC-clones. Both animals were probably hybrids from crosses with the wild pig (2n=36) present in the Nebrodi mountains where Nero Siciliano is reared with extensive or semi-extensive systems. SCE-test applied on all studied animals revealed no statistical differences between the SCE-mean number of Casertana (7.13±3.20) and Nero Siciliano (6.87±3.12) breeds. Statistical differences were found between SCEs mean values of males (7.26±3.38) and females (6.59±2.90) of Nero Siciliano breed, as well as between females of Casertana (7.24±3.26) and Nero Siciliano (6.59±2.90) breeds, while no statistical differences were found between SCE mean values of males of Casertana (6.98±3.10) and Nero Siciliano (6.45±2.97) breeds, as well as between males and females of Casertana breed.