Productive Longevity and Reproductive Quality of Holstein Cows of Foreign Breeding

Abstract

The aim of this work is to determine the productive longevity of Holstein cows of different breedings. The results of the research showed that Finnish animals were superior in life expectancy and productive longevity, exceeding German breeding cows by 74 days (P<0.05) and Hungarian cows by 24 days, and by 0.06 and 0.12 lactations in the productive period respectively. At the same time, according to the level of average productivity per lactation and lifelong milk yield, the highest rates were established for the group of Hungarian cows. So, their average milk yield per lactation was higher: compared to other groups by 529.2 kg and 561.8 kg or 7.6 % and 8.1%; lifelong milk yield by 1305.5 kg and 996 kg (5.6 % and 4.2%); per one day of calving interval - by 0.64 kg and 0.8 kg (3.6 % and 4.6%) and per one day of life - by 0.56 kg and 0.60 kg or by 3.2 % and 5.6%. In the context of the group of cows of the German and Finnish breeding, no significant differences were noted by these indicators. The duration of pregnancy in experimental cows ranged from 285-289 days. The analysis of the obtained data indicates that the cellular protection indicators of Holstein cows are within the physiological norm. So, phagocytic activity, which expresses the percentage of active leukocytes participating in phagocytosis to the total number of counted neutrophilic leukocytes, is higher in animals of the German breeding compared with Hungarian animals - by 13.2% and with Finnish ones - by 13.4%. The phagocytic index is defined by the average number of phagocytosed microorganisms per active leukocyte and characterizes the intensity of phago-cytosis. In our experiment, the intensity of phagocytosis was higher in the German cows and amounted to 8.42, which exceeds this indicator by 11.4% compared with animals of the Hungarian breeding and by 3.3% compared to the Finnish animals.

Productive Traits and Reproductive Capacity of First-Calf Cows at Different Selection Options

“…Holstein cows as a whole were characterized by a relatively strong constitution, a proportionally developed and slightly elongated body with average live weight, deep chests with well-defined milk veins, glandular and properly attached bath-like, and cup-shaped udder, with an average intensity of milk yield (2.12-2.4 kg/min). The yield was for 1 st lactation 6465.9-6951.2 kg, the 2 nd lactation 7463.5-7706.2 kg, according the 3 rd lactation 8254.2-8297.7 kg of milk (Semenov et al, 2021).…”

“…The category of first-calf heifers is an effective method of increasing dairy productivity, adjusting their intensity can fully realize the genetic potential and preserve the health of the animal, thereby extending the duration of the productive life (Kalimoldinova et al, 2019;Semenov et al, 2021;Yelemesov and Baimukanov, 2020).…”