Morse D, DeLorenzo M A, Wilcox C J, Natzke R P, Bray D R
Dairy Science Department, University of Florida, Gainesville 32611.
J Dairy Sci. 1987 Oct;70(10):2168-75. doi: 10.3168/jds.S0022-0302(87)80270-9.
Clinical mastitis records for 6.5 yr (July 1977 through November 1983) from a large north Florida dairy were analyzed. Observed frequencies of clinical mastitis were calculated in 7240 Holstein and Jersey lactations. Least squares analyses used Holstein and Jersey lactations greater than 200 d and limited maximum parity to 5 (6732 lactations, 5738 episodes). Solutions for number of occurrences of clinical mastitis adjusted for month of parturition and breed effects were .47, .59, .94, 1.27, and 1.50 for parities 1 through 5. Solutions for number of occurrences across lactation in Holsteins was greater than for Jerseys (1.28 vs. .63). Solutions for occurrence of first episode in Holsteins increased from .35 in parity 1 to .71 in parity 5. Occurrence of episodes two through five increased as parity increased. Similar trends were found in Jerseys with the exception of parity 2. Correlation of residuals between specific episodes increased as episode increased. From episode 2 through 5 probability of another occurrence of clinical mastitis was greater than .75. Solutions for proportion of occurrences of clinical mastitis occurring during the first 35 d postcalving were .60, .36, .31, .30, and .28 for parities 1 through 5. Clinical mastitis in first parity cows occurred primarily during the first 35 d postcalving.
对佛罗里达州北部一家大型奶牛场6.5年（1977年7月至1983年11月）的临床乳腺炎记录进行了分析。计算了7240头荷斯坦奶牛和泽西奶牛泌乳期临床乳腺炎的观察频率。最小二乘法分析使用了泌乳期超过200天且最大胎次限制为5的荷斯坦奶牛和泽西奶牛泌乳期（6732个泌乳期，5738次发病）。根据产犊月份和品种效应调整后的临床乳腺炎发病次数的解，第1至5胎分别为0.47、0.59、0.94、1.27和1.50。荷斯坦奶牛整个泌乳期发病次数的解大于泽西奶牛（1.28对0.63）。荷斯坦奶牛第一胎首次发病的解从0.35增加到第5胎的0.71。第二至五胎的发病次数随着胎次增加而增加。泽西奶牛也发现了类似趋势，但第二胎除外。特定发病之间残差的相关性随着发病次数增加而增加。从第2次发病到第5次发病，再次发生临床乳腺炎的概率大于0.75。第1至5胎产后前35天内临床乳腺炎发病比例的解分别为0.60、0.36、0.31、0.30和0.28。第一胎奶牛的临床乳腺炎主要发生在产后前35天。
