Екстер’єрно-конституційні особливості корів-первісток молочних порід

Abstract

Goal. To study the exterior features of cows of different genotypes obtained by purebred breeding and crossbreeding. Methods. Analysis of experimental research on the application of effective breeding methods, theoretical analysis, formulation of hypotheses, genealogical, biometric and statistical methods, and assessment of productive qualities of animals. Results. It was established that the breeders of Holstein, Montbeliard, and Norwegian red breeds were sufficiently consolidated in terms of exterior features and influenced the formation of the desired characteristics in their offspring. High rates of single milk yield of experimental cows indicated good development of the parenchyma and capacitive system of the udder. The bath-shaped form of the udder had mostly (73.7–76.7%) first-born cows obtained from Holstein breeders. This udder was quite close to the abdomen of the animals, forming only a small corner of the line of the abdomen and the front of the udder. Among the local firstborns of the genus 1/2UCheR1/2M, 63.4% of cows had a bath-shaped udder, and 33.4% — were cup-shaped. The conditional udder volume of first-born cows was almost the same and averaged from 2561.3±93.66 to 2985.4±94.48 cm3, respectively. This made it possible to obtain average daily milk yields of 26.6±1.54-31.0±1.94 kg from first-borns during 2 times milking. With the average degree of reliability (P>0.99) milk yield of cows correlated with measurements of the girth of the chest behind the shoulders (r=+0.210+0.254), oblique length of the torso (r=+0.212+0.241), and width in the macula (r=+0.137+0.185). A high degree of correlation was found between the amount of milk and udder measurements: width (r=+0.514+0.587; P>0.999), girth (r=+0.506+0.587; P>0.999), and volume (r=+0.504+0.650); P>0.999). Conclusions. The use of genetic material from the Norwegian Red and Holstein breeds contributed to the formation of an array of animals with a well-defined milk type. The possibility of first-borns with a rough, massive skeleton and polymastia in the herd should be taken into account when selecting breeders of Montbeliard breeds. There is a close relationship between milk productivity and udder measurements, which indicates the possibility of indirect selection of cows for milking at the beginning (1–2 months) of the first lactation.