TY - JOUR AU - Khmelnychyi, Leontiі Mykhailovych AU - Khmelnychyi, Serhii Leontievych PY - 2021/10/12 Y2 - 2024/03/29 TI - POPULATION AND GENETIC PARAMETERS OF LINEAR CONFORMATION TRAITS COWS FIRSTBORN UKRAINIAN BLACK-AND-WHITE DAIRY BREED JF - Bulletin of Sumy National Agrarian University. The series: Livestock JA - ls VL - IS - 3 (46) SE - Articles DO - 10.32845/bsnau.lvst.2021.3.2 UR - https://snaubulletin.com.ua/index.php/ls/article/view/429 SP - 7-12 AB - Researches on the study of population-genetic parameters of linear type traits of cow’s firstborn of the Ukrainian Black-and-White dairy breed were conducted in the herd of a private enterprise of the Pidlisnivs’ka branch of PE "Buryns’ke" in Sumy district. Conformation type assessment of cows firstborn was performed according to the method by linear classification by the latest ICAR recommendations at the age of 2-4 months after calving according to two systems - 9-score scale, with a linear description of 18 conformation body parts and 100-score classification system taking into account four sets of selection traits that characterize: the severity of dairy type, body development, limbs condition and udder morphological qualities. The highest level of reliable positive relationship with the milk yield per lactation of cows firstborn was found according to the conformation group traits, characterizing the severity of the dairy type of cows (r = 0.451), body development (r = 0.434), qualitative indicators of udder morphological traits (r = 0.468) and by the final type score (r = 0.488). A positive relationship with milk yield was observed by a number of individual descrip-tive conformation traits: height at sacrum (r = 0.358), body depth (r = 0.413), angularity (r = 0.469), rump width (r = 0.431), pelvic limbs posture (r = 0.374), fore (r = 0.466) and rear (r = 0.347) udder attachment, central ligament (r = 0.258) and locomotion (r = 0.334). Body condition score negatively correlated with milk yield (r = 0.338). Sufficient for effective selection the level of heritability coefficients of cows linear traits was found in the vast majority of group traits that characterize the dairy type (0.356), body develop-ment (0.312), udder (0.415) and overall type assessment (0.487), and by descriptive traits : height at sacrum (0.284), chest width (0.144), body depth (0.347), angularity (0.436), rump width (0.274), pelvic limbs posture (0.322), fore (0.357) and rear (0.258) udder attachment and central ligament (0.233). The established significant and reliable correlation variability of group and descriptive con-formation body parts with milk yield during the first lactation confirmed the possibility and expediency of simultaneous selection by productivity and type. ER -