Gipson T A, Vogt D W, Massey J W, Ellersieck M R
J Am Vet Med Assoc. 1985 Mar 15;186(6):580-2.
Scrotal circumference measurements were analyzed to develop appropriate adjustment factors for age and body weight differences in beef bulls. Age, body weight, and scrotal circumference measurements were collected on 863 Angus, 753 Polled Hereford, and 302 Simmental bulls from the Missouri tested bull sale, 1169 Polled Hereford bulls from the American Polled Hereford Association, and 465 Polled Hereford and 264 Simmental bulls from Nichols Farms in Bridgewater, Iowa. Within sources, data were subdivided into appropriate subsets and then each subset was statistically analyzed. Adjustment factors to remove differences in scrotal circumference due to age and body weight were developed for bulls of each of the 3 breeds studied.
分析阴囊周长测量数据，以制定针对肉用公牛年龄和体重差异的适当调整因子。从密苏里州种公牛拍卖会的863头安格斯公牛、753头无角海福特公牛和302头西门塔尔公牛，美国无角海福特协会的1169头无角海福特公牛，以及爱荷华州布里奇沃特市尼科尔斯农场的465头无角海福特公牛和264头西门塔尔公牛中收集年龄、体重和阴囊周长测量数据。在各个来源中，数据被细分为适当的子集，然后对每个子集进行统计分析。针对所研究的3个品种的每一种公牛，都制定了消除因年龄和体重导致的阴囊周长差异的调整因子。
