The productivity and quality increase of the animal products is coming to be of big economic interest. The prolactin (PRL) is an essencial hormone for the reproductive sucess and its receptor (PRLR) has been detected in several tissues (Kelly et al., 1991). The PRLR gene has been recently mapped to pig chromosome 16 (Vincent et al., 1997).This research was aimed at analyzing the PRLR genotypical frequency in three different swine races, Landrace, Large White and Pietrain and correlate the genotypes with characteristics of economic interest. It was analyzed 124 animals. The DNA was extracted from the pig blood and submited to PCR-RFLP technique, to the genotypes determination of the prolactin receptor gene. The statistics analysis showed that the PRLR genotypes had an effect on the daily average weight of the Landrace race (p<0,0135). The averages of EDP (Expected Difference of Progeny) in daily average weight of the Landrace race were also different in relation to the genotypes (p<0.0610), confirming the real data analysis of daily average weight increase. Attended selection methods by markers, together with traditional seletion methods can be used to increase and accelerate the improvement of economic interest characteristics in pigs, while the prolactin receptor gene (PRLR) can be used as a molecular marker for the real daily average weight increase and its EDP.
Prolactin; Receptor; Gene; Pig
