The quantitative genetic analysis of linear type traits in dairy cattle farms in that members of Çanakkale cattle breeder's association

ABSTRACTThis research was carried out to examine the traits of linear type points whichmay have indirect affects on yield. Status of the morphological defects with systematicenvironmental factors may affect grading in Çanakkale. Furthermore, genotype xenvironment interactions were studied in the concept of linear type traits using the bullswhose sperms were used for artificial insemination in Çanakkale.Records of 973 Holstein dairy cattle registered to Cattle Breeder?s Associationof Çanakkale located at 226 different farms were graded for linear type traits by 24different graders.The systematic environmental factors, district, parity, farm level and days inmilk were significant statistically (P≤0.05) in most of the type traits.The morphological defects affected the traits of linear type points at differentdirections.All the traits except total score (h2= 0.47 ± 0.25), udder score (h2 = 0.62 ± 0.26)and teat placement (h2 = 0.45 ± 0.24) had low to medium heritabilities (h2 = 0.06 -0.30). Correlations between catalogue value and breeding values were low forÇanakkale. These two indicates that there is a genotype x enviroment interaction forthese traits.Key Words: Genotype x environment interaction, linear type traits, systematicenvironmental factors, morphological defects, genetic parameters.II