Smidt W J, Zuidberg C
Gezondheidsdienst voor Dieren in Overijssel en Flevoland, Zwolle.
Tijdschr Diergeneeskd. 1988 Jun 15;113(12):673-6.
Four groups of cows, each group comprising from 5,000 to 5,500 animals, were inseminated with 7.5, 10, 15 and 20 millions of living and dead spermatozoa respectively. This was deep frozen semen in 0.25 ml straws. The fertilisation rates of the groups did not differ significantly, even when the fertility levels of the twenty-eight bulls involved were taken into account.
四组奶牛，每组有5000到5500头，分别用750万、1000万、1500万和2000万个活精子和死精子进行授精。这是装在0.25毫升细管中的冷冻精液。即使考虑到所涉及的28头公牛的生育水平，各实验组的受精率也没有显著差异。
