Chromosomal Damage in Pigs from a Farm of Central Argentina

Abstract

Cytogenetic analysis of peripheral blood lymphocytes was carried out in ten hypoprolific pigsfrom a farm located near Rio Cuarto National University, where sows gave birth to no more thanthree piglets in their later farrows.
Blood samples from seven sows and one boar were obtained in a first instance. Animalsshowed a high frequency of chromosomal abnormalities (ranging from 19 to 32 per 100 cells scored). Chromosomal aberrations were mainly chromatid breaks, chromatid exchanges (triradials, quadriradials) and chromosome fragments. In addition, 15% of the metaphases showed chromosomal pulverization. A sow and its piglet were studied in a second sampling detecting only chromosome pulverization aberration type (80% of the cells scored in average). Chromosomal localizationof breaks was done with GTG banded metaphases. At least, eight chromosomes were involved, thehighest frequency of breaks was located in the longest telocentric (chromosome n° 13). “Chromosome pulverization” has been associated to virus infection. All studied adult animals werevaccinated against Swine Fever, Aujeszky disease is endemic for the region. Consequently, chromosomaldamage could be induced by subclinical viral infection. Chromosomal anomalies might be relatedto the reproductive impairment of pigs; however, further studies would be necessary to identifythe clastogenic agent.