Helle O, Hilali M
Acta Vet Scand. 1973;14(1):57-68. doi: 10.1186/BF03547410.
The total and differential oocyst counts of the different Eimeria species in the faeces of Norwegian ewes and lambs were investigated at weekly intervals during the grazing period on permanent and new pastures. The total oocyst counts of lambs on permanent pastures were significantly higher than those on new pastures 3–6 weeks after the beginning of the grazing period. This demonstrates that the oocysts had survived the winter in the pasture. Species differentiation indicated that E. ahsata, E. arlongi, E. crandallis, E. ninakohlyakimovae, E. faurei and E. parva are able to survive the winter in the pasture. E. crandallis occurred in the greatest numbers, and this species might be an important contributor to the clinical symptoms which are frequently observed in Norwegian lambs about 2–3 weeks after the beginning of the grazing period. There were on the other hand, indications that E. pallida has little ability to survive the winter in the pasture. The results were generally similar for most of the species during 2 successive years. The total number of oocysts in the faeces of ewes was low on new as well as on permanent pastures, and the species differentiation showed negligible differences. Consequently, it was concluded that the ewes could not be the source of the high oocyst numbers in lambs on the permanent pastures.
在永久牧场和新牧场上放牧期间，每周对挪威母羊和羔羊粪便中不同艾美耳球虫种类的卵囊总数和分类计数进行调查。在放牧期开始3至6周后，永久牧场上羔羊的卵囊总数显著高于新牧场上的羔羊。这表明卵囊在牧场中度过了冬天。种类区分表明，阿氏艾美耳球虫、长形艾美耳球虫、克兰氏艾美耳球虫、纳氏艾美耳球虫、法氏艾美耳球虫和微小艾美耳球虫能够在牧场中度过冬天。克兰氏艾美耳球虫数量最多，该种类可能是导致挪威羔羊在放牧期开始约2至3周后经常出现的临床症状的重要因素。另一方面，有迹象表明苍白艾美耳球虫在牧场中度过冬天的能力较弱。连续两年中，大多数种类的结果总体相似。新牧场和永久牧场上母羊粪便中的卵囊总数都很低，种类区分显示差异可忽略不计。因此，得出的结论是，母羊不可能是永久牧场上羔羊卵囊数量高的来源。
