Department of Animal Sciences, 1675 Observatory Drive, University of Wisconsin, Madison, WI 53706, USA.
Animal. 2010 Aug;4(8):1283-96. doi: 10.1017/S1751731110000856.
The five Northern European short-tailed sheep breeds present in North America are the Finnsheep, Romanov, Icelandic, Shetland and Gotland. The Finnsheep and Romanov were first imported in 1966 and 1986, respectively, for their high reproductive performance. The Shetland, Icelandic and Gotland breeds were first imported in 1980, 1985 and 2005, respectively, for the uniqueness of their physical appearance and their unique fleeces desired by fiber craftspeople. There have been no scientific studies conducted on the performance of the Shetland, Icelandic or Gotland breeds relative to other breeds of sheep in North America. However, the Shetland and Icelandic breeds have become very popular in the United States and ranked 9th and 18th, respectively, among 35 breeds of sheep for number of purebred animals registered in 2008. The performance of the Finnsheep breed in North America relative to domestic breeds has been thoroughly investigated. Compared to several domestic purebreds and crosses, sheep with Finnsheep breeding had a younger age at puberty, greater fertility to autumn mating, greater litter size, greater survival to weaning, similar growth rate, similar subcutaneous fat thickness, smaller loin muscle area and greater percentage of kidney and pelvic fat. Each 1% increase in Finnsheep breeding in ewes was associated with approximately 0.01 more lambs born per ewe lambing. In North American studies, Romanov ewes were superior to Finnsheep ewes for reproductive rate and lamb production per ewe under both autumn and spring mating. Lambs of the two breeds were similar for survival, growth and carcass traits. Romanov and Romanov-cross ewes produced fleeces that were heavily contaminated with medulated and colored fibers and were of very low commercial value. Three composite breeds containing 25% to 49% Finnsheep breeding (Polypay, Rideau Arcott and Outaouais Arcott) were developed in North America and are now more popular than the Finnsheep breed.
北美地区现有的 5 个北欧短尾绵羊品种分别为芬兰绵羊、罗曼诺夫羊、冰岛羊、设得兰群岛羊和哥得兰羊。1966 年和 1986 年，分别首次引进芬兰绵羊和罗曼诺夫羊，因其具有较高的繁殖性能。1980 年、1985 年和 2005 年，首次引进设得兰群岛羊、冰岛羊和哥得兰羊，因其外貌独特，且羊毛具有独特的纤维特性，深受纤维工艺品工匠的喜爱。目前尚未对设得兰群岛羊、冰岛羊或哥得兰羊品种与北美其他绵羊品种的性能进行科学研究。然而，设得兰群岛羊和冰岛羊在美国非常受欢迎，在 2008 年登记的 35 个绵羊品种中，其纯种动物数量分别排名第 9 位和第 18 位。芬兰绵羊品种在北美的表现已得到充分研究。与几种国内纯种绵羊和杂交品种相比，具有芬兰绵羊血统的绵羊初情期更年轻、秋季配种的繁殖力更强、产仔数更多、断奶成活率更高、生长速度相似、皮下脂肪厚度相似、腰角肌肉面积更小、肾周和骨盆脂肪比例更高。母羊中每增加 1%的芬兰绵羊血统，平均每只母羊产羔数就会增加约 0.01 只。在北美研究中，罗曼诺夫羊在秋季和春季配种时，繁殖率和每只母羊的产羔数均优于芬兰绵羊。这两个品种的羔羊在成活率、生长和胴体性状方面相似。罗曼诺夫羊和罗曼诺夫杂交羊所产的羊毛严重污染有卷曲纤维和有色纤维，商业价值非常低。在北美开发了三个含有 25%至 49%芬兰绵羊血统的复合品种（波旁羊毛羊、里多弧形羊和奥塔瓦弧形羊），它们比芬兰绵羊品种更受欢迎。
