Anderson B C, Bulgin M S, Adams S, Duelke B
J Am Vet Med Assoc. 1985 Feb 15;186(4):391-3.
A condition of firm udders in periparturient ewes, with little or no milk available at the teat, was associated with negative bacterial cultures of mammary tissue, isolation of ovine progressive pneumonia virus from mammary tissue, lymphocytic accumulations in mammary tissue, especially around ducts, and antibody to ovine progressive pneumonia virus in sera. Milk was present in the glands, but was not adequately transported through the duct system. The cull rate of ewes with this condition was reported by producers and veterinarians to be less than 5% in flocks where the condition was recognized, but approximately 10% of ewes were apparently affected in at least 1 flock.
围产期母羊乳房坚实，乳头处几乎没有或没有乳汁，这与乳腺组织细菌培养阴性、从乳腺组织中分离出绵羊进行性肺炎病毒、乳腺组织尤其是导管周围有淋巴细胞聚集以及血清中存在绵羊进行性肺炎病毒抗体有关。乳腺中有乳汁，但未能充分通过导管系统运输。据生产者和兽医报告，在识别出这种情况的羊群中，患有这种疾病的母羊淘汰率低于5%，但在至少一个羊群中，约10%的母羊显然受到了影响。
