The aim of the present study was to evaluate the changes in selected production and functional traits of Polish Holstein-Friesian cows after switching from a conventional (CMS) to an automatic milking system (AMS). The study consisted of 3398 Polish Holstein- Friesian dairy cows, from 16 herds in which CMS was changed to AMS. Cows were in their 1^st (L1) or 2^nd lactation (L2). The data consisted of milk yield [MY, kg], fat content [FC, %], protein content [PC, %], dry matter [DM, %], lactose content [LC, %], urea content [MU, mg/l], somatic cell count [SCC, thous./ml] and score [SCS, log]. The milking system had a significant impact on milk yield, fat, lactose, dry matter and urea contents. Regardless of lactation number, milk derived from CMS was characterised by higher values for FC, PC, DM SCC and SCS, while milk from AMS had higher MY, LC and MU. Multifactor analysis of variance also confirmed significant effect of herd, season, herd × milking system interaction on SCS in milk of cows in L1. In the studied herds change from CMS to AMS was evaluated separately for cows in L1 and L2. The transitioning from CMS to AMS resulted in the decrease of fat content in 6 L1 and 7 L2 herds, dry matter in 8 L1 and 5 L2 herds. SCS in milk also decreased in 4 L1 and 5 L2 herds. The change caused the increase of MY in 11 L1 and 9 L2 herds, lactose content in 6 L1 and 4 L2 herds and urea content in 9 L1 and 10 L2 herds. AMS may positively affect milk yield and health status, however, the change of milking system should be also accompanied by the change in herd management.

中文翻译：

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传统和自动挤奶系统中波兰荷斯坦奶牛的产奶量，成分和质量的比较

本研究的目的是评估从传统（CMS）切换到自动挤奶系统（AMS）后，波兰荷斯坦-弗里斯兰奶牛的选定生产和功能性状的变化。该研究由3398头波兰荷斯坦-弗里斯兰奶牛组成，从16个牧群中将CMS改为AMS。牛在其1^日（L1）或2^次哺乳期（L2）。数据包括牛奶产量[MY，kg]，脂肪含量[FC，％]，蛋白质含量[PC，％]，干物质[DM，％]，乳糖含量[LC，％]，尿素含量[MU，mg / l]，体细胞计数[SCC，千/ ml]和得分[SCS，log]。挤奶系统对牛奶产量，脂肪，乳糖，干物质和尿素含量有重大影响。无论泌乳数如何，来自CMS的牛奶都具有较高的FC，PC，DM SCC和SCS值，而来自AMS的牛奶具有较高的MY，LC和MU。多因素方差分析还证实了L1奶牛的牛群中，牛群，季节，牛群×挤奶系统的相互作用对SCS有显着影响。在研究中，分别评估了L1和L2奶牛从CMS到AMS的变化。从CMS向AMS的过渡导致6个L1和7个L2牛群的脂肪含量降低，8 L1和5 L2牛群中的干物质。4 L1和5 L2牛群中牛奶中的SCS也降低了。这种变化导致11 L1和9 L2畜群的MY增加，6 L1和4 L2畜群的乳糖含量以及9 L1和10 L2畜群的尿素含量增加。AMS可能对产奶量和健康状况产生积极影响，但是，挤奶系统的改变也应伴随着牛群管理的改变。