Analysis of milking indicators of different cow breeds
Cow milking is considered as a laborious and time-consuming job at livestock farms [1]. The milking process represents one of the most important tasks on a dairy farm. On farms with conventional milking systems, it accounts for roughly a third of farm’s total labor demand [2]. Increasing the milk flow rate at which milking is terminated can shorten milking time and increase milking efficiency [3]. It is important that milking speed-related traits present high heritability estimates for higher selection responses in breeding programs aiming to breed for more efficient and adapted animals for milking systems [4]. The aim of the study was to analyze the milking indicators of different cow breeds. Materials and methods. In the study farm, cows are kept loose all year round, in a modern cold-type barn. During summer, the animals are not grazed, and they are fed a complete diet that meets their physiological needs. Cows are milked 2x20 side-by-side in a milking parlour. The milking data of 420 cows were collected, 140 of which were of the Lithuanian Red breed, 62 of the Swedish Red and White and 218 of the White and Red Holstein breeds. For the analysis of the data, statistical indicators were calculated for each evaluated trait (milk yield at milking, milking duration, average milk flow, maximum milk flow, milk yield in the first 2 minutes, milk flow in time intervals: 0–15 s, 15–30 s, 30–60 s, 60–120 s): arithmetic mean, mean error and statistical reliability of the data (P). The obtained results were considered statistically significant when P < 0.05. Results and conclusion. We found that Lithuanian Red cows produced 0.51 kg more milk than White and Red Holsteins and 0.29 kg more milk than Swedish Red and White. The milk yield in the first two minutes of milking was 0.31 kg higher in the Lithuanian Red cows than in the Swedish Red and White cows and 0.38 kg higher than in the White and Red Holstein cows. The average milking time was 6.19 minutes. The milking time of the White and Red Holstein cows was 0.11 min longer than that of the Lithuanian Red cows (P < 0.01) and 0.17 min longer than that of the Swedish Red and White Holstein cows (P < 0.01). The average milk flow of Lithuanian Red cows was only 0.03 kg/min higher than that of Swedish Red and White and 0.11 kg/ min higher than that of White and Red Holstein cows. The highest milk flow rate of the Lithuanian Red and Swedish Red and White breeds was 0.22 kg/min higher than that of the White and Red Holstein breed. The milk flow rates of the Lithuanian Red cows at the time intervals 0–15 s, 15–30 s, 30–60 s and 60–120 s were found to be 0.05, 0.23, 0.11 and 0.17 kg/min higher than that of the Swedish Red and White cows, and 0.04, 0.21, 0.21 and 0.2 kg/min higher than that of the White and Red Holstein cows. In conclusion, the Lithuanian Red cows on the farm produced more milk, milked faster and had higher milk flows.