Exterior of cows of the Ukrainian black-spotted dairy breed, obtained under various selection options

Abstract

Analysis of the effectiveness of evaluating inline and inter-line variants of combinations by type and finding their best variants in practical selective breeding is a relevant task that allows obtaining offspring of the desired quality. The purpose of this study is to figure out the specific features of the body structure of the firstborn cows of the Ukrainian blackspotted dairy breed of the western inbred type, depending on their origin, as well as to establish the type of inheritance of these indicators in line crosses based on the results of the evaluation by type. The study found the types of selection through genealogical analysis of pedigrees, linear evaluation of cows by type according to two evaluation systems – linear description of individual articles of the exterior on a 9-point scale and evaluation of complexes of exterior features of the animal type on a 100-point scale, obtained results were evaluated according to Student’s t-test. Using the scheme, it was found that the firstborn cows obtained as a result of the inline selection are characterized by optimal scores by type. However, animals from the Valianta 1650414 line received the highest ratings for linear traits of height at the withers, width of chest and rear, body depth. The study analysed the evaluation of firstborn cows by type, obtained in the interline selection, and it was found that the indicators of linear evaluation by type of cross lines correspond to and prevail over the average values for the breed. Cross cows ♂Valianta 1650414 x ♀Eleveishna 1491007 received the highest score for milk type on a 100-point scale. It was proved that most of the evaluated traits in line crosses were inherited according to the intermediate type. However, in the cross ♂Chifa 1427381 x ♀Eleveishna 1491007, the evaluation of individual traits (height, chest width, angle of withers, rear attachment, and depth of udder) statistically probably exceeded the values of the corresponding evaluations of the firstborns of the paternal and maternal lines, and the dominance of the maternal line was observed in the cross-breed cows ♂Chifa 1427381 x ♀Valianta 1650414 according to the value of the assessment of individual udder traits. The obtained results will allow performing optimal selection of parent pairs from animals evaluated by type for selection and breeding work with cattle herds to consolidate them by type

Keywords

• cows
• firstborn cows
• exterior assessment
• breeding selection
• cross lines
• inheritance