Pavlásek I
Státní veterinární ústav, Praha.
Vet Med (Praha). 1993;38(10):629-38.
Black-headed full (L. ridibundus L.) represents a new host of C. baileyi Current, Upton and Haynes, 1986. In 1991-1992 during the months of May-July six localities in three regions of the Czech Republic were studied by examining in total 264 not flying gull chicks (4-30 days of age), applying the methods after Pavlásek (1987a, b, 1991). Cryptosporidia were found in gulls in all localities and spontaneous infection during the period under study occurred in 27.5-100% of birds (Tab. II, Fig. 1). The size of oocysts was 6.2-6.4 by 4.8-5.8 microns with means of 6.4 by 4.9 microns. The oocyst index (width/length) was 0.75-0.93 with means of 0.77. C. baileyi infection was demonstrated in 22 out of 24 dead gull chicks submitted to autopsy. From two localities total 15 gulls were killed, the examination of which revealed oocyst occurring in masses in the fluid from cloacal washes. Asexual and sexual endogenous developmental stages, including C. baileyi oocysts, in all birds undergoing autopsy were localized in caudal part of colon (1-2 cm from opening into cloaca) and in the cloaca. Findings of cryptosporidia were very frequent, above all, in the bursa Fabricii. In two dead and six with snoring disease, subsequently killed gull chicks, respiratory form of infection was demonstrated with simultaneous proof of endogenous developmental stages including oocysts in smears of mucous epithelium of sinus infraorbitalis, larynx, trachea and bronchi using the Giemsa stain after fixation with absolute methanol. An experimental transmission of infection by isolates of C. baileyi oocysts from gulls to five 4-day chicks (Gallus gallus f. domestica) using the dosis of 5 x 10(5) oocysts/chick was successful. The prepatent period lasted 4 days. On day 3 and 6 after infection two chicks died. The developmental stages of the protozoon were found in the lower part of colon, in cloaca and in bursa Fabricii. In chicks dead on day 6 after infection asexual stages of cryptosporidia were found in trachea and in bronchi. One chick survived the infection and excretion of oocyst (patent period) lasted 14 days. In this bird cloacal, bursal as well as respiratory form of C. baileyi infection was found. Control chicks were negative during the observation of 30 days. Oocysts from gulls do not lose their viability even after 8-month storage in the 2.5% solution of K2Cr2O7 at the temperature of 4 degrees C.(ABSTRACT TRUNCATED AT 400 WORDS)
黑头鸥（L. ridibundus L.）是贝利隐孢子虫（Current, Upton and Haynes, 1986）的新宿主。1991年至1992年5月至7月期间，对捷克共和国三个地区的六个地点进行了研究，共检查了264只未飞行的鸥雏（4至30日龄），采用了帕夫拉塞克（1987a、b、1991）之后的方法。在所研究期间，所有地点的鸥中均发现了隐孢子虫，27.5%至100%的鸟类发生了自然感染（表二，图1）。卵囊大小为6.2 - 6.4×4.8 - 5.8微米，平均为6.4×4.9微米。卵囊指数（宽度/长度）为0.75 - 0.93，平均为0.77。在提交尸检的24只死亡鸥雏中，有22只证明感染了贝利隐孢子虫。从两个地点共捕杀了15只鸥，检查发现泄殖腔冲洗液中有大量卵囊。在所有接受尸检的鸟类中，无性和有性内源性发育阶段，包括贝利隐孢子虫卵囊，位于结肠尾部（距泄殖腔开口1 - 2厘米）和泄殖腔内。隐孢子虫的发现非常频繁，尤其是在法氏囊中。在两只死亡和六只患有呼噜病（随后被宰杀）的鸥雏中，通过用绝对甲醇固定后使用吉姆萨染色，在眶下窦、喉、气管和支气管的粘液上皮涂片上证明了呼吸道形式的感染以及包括卵囊在内的内源性发育阶段。使用每只雏鸡5×10⁵个卵囊的剂量，将来自鸥的贝利隐孢子虫卵囊分离物成功地实验性传播给了五只4日龄雏鸡（家鸡）。潜伏期为4天。感染后第3天和第6天，两只雏鸡死亡。在结肠下部、泄殖腔和法氏囊中发现了原生动物的发育阶段。在感染后第6天死亡的雏鸡中，在气管和支气管中发现了隐孢子虫的无性阶段。一只雏鸡在感染后存活下来，卵囊排泄（排虫期）持续了14天。在这只鸟中发现了泄殖腔、法氏囊以及呼吸道形式的贝利隐孢子虫感染。对照雏鸡在30天的观察期内为阴性。来自鸥的卵囊即使在4℃下于2.5%的重铬酸钾溶液中储存8个月后仍不失活力。
