Short communication Relation of porcine myogenin gene PCR/RFLP MspI and reproduction traits of the Czech Large White sows P. Humpolíček a , T. Urban a, ⁎ , Z. Tvrdoň b a Department of Animal Morphology, Physiology and Genetics, Mendel University of Agriculture and Forestry, Zemědělská 1, 61300 Brno, Czech Republic b Genoservis, Co. Olomouc, Jožky Jabůrkové 1, 779 74 Olomouc, Czech Republic Received 3 August 2006; received in revised form 12 February 2007; accepted 22 February 2007 Abstract Reproduction traits are highly important for pigs producers because of effect on economic efficiency. Hence, breeders as well as geneticists try to find the way to improve the reproduction traits. Because the protein coded by the myogenin gene (MYOG) is necessary for regulation of skeletal muscles development during embryogenesis, many authors have studied its influence on the meat traits of pigs. The aim of our study was to determine the effect of myogenin gene on the sows' reproduction traits. There were included 529 litters of 107 Czech Large White sows. Effects on the age of the first conception, service period, insemination index, average birth weight of piglets, average weights of litter at the age of 21 days, total number of born piglets, number of piglets born alive and number of weaned piglets were studied. For studying the influence of myogenin gene on chosen traits we used the mixed linear model procedure REML and in one case general linear model. Significant effects of myogenin gene on the age of first conception, the insemination index and on the litter size were proved. © 2007 Elsevier B.V. All rights reserved. Keywords: Porcine myogenin gene; MYOG; Reproduction traits; Czech Large White; Pig 1. Introduction Efficiency of production of livestock is highly influenced by reproductive success, especially in litterbearing species. The gene of myogenin (MYOG) is a member of a family of transcription factors that are specific to skeletal muscle (Wright et al., 1989). In the pig, primary muscle fibre formation takes place in the period around day 35, and secondary muscle fibre formation is taking place in the period at approximately day 65 of gestation (Wigmore and Tickland, 1983). The myogenin and the MYF3 gene induce the terminal transformation of myoblasts into myofibers (Te Pas and Visscher, 1994). Because of that, the myogenin gene is considered as a candidate gene for meat traits. The significant effect of the myogenin gene on birth weight, growth rate and lean weight has been detected by Te Pas et al. (1999). By contrast, they did not find any differences for backfat thickness. An impact of the MYOG gene on reproductive traits was noticed only by Horák et al. (2004). They watched the influence of this gene in Přeštice Black-Pied sows which have been declared as the genetic resource in the Czech Republic. The aim of our study was to determine the impact of the myogenin gene Livestock Science 110 (2007) 288 – 291 www.elsevier.com/locate/livsci ⁎ Corresponding author. Tel.: +420 5 4513 3182; fax: +420 5 4513 3176. E-mail address: urban@mendelu.cz (T. Urban). 1871-1413/$ - see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.livsci.2007.02.015