Christensen B M, Barnes H J, Rowley W A
J Wildl Dis. 1983 Jul;19(3):204-13. doi: 10.7589/0090-3558-19.3.204.
Vertebrate host specificity, experimental laboratory vectors, and a description of Plasmodium (Novyella) kempi sp. n. from eastern wild turkeys (Meleagris gallopavo silvestris Vieillot) in Iowa are presented. Plasmodium kempi is infective for domestic turkeys, bobwhites (Colinus virginianus), chukars (Alectoris graeca), guinea fowl (Numida meleagris), peacocks (Pavo cristatus), and canaries (Serinus canaria), produces a transient infection in mallards (Anas platyrhynchos) and domestic geese (Anser anser), but will not infect ring-necked pheasants (Phasianus colchicus), pigeons (Columba livia), Japanese quail (Coturnix coturnix), leghorn white chickens (Gallus gallus), or starlings (Sturnus vulgaris). Oocysts and (or) sporozoites were recovered from 68% (84/124) and 98% (60/61) of the Culex pipiens pipiens and C. tarsalis examined, respectively. Oocysts developed faster and sporozoites invaded the salivary glands sooner in C. tarsalis (6 days) than in C. p. pipiens (7 days). Culex tarsalis transmitted P. kempi more effectively than C. p. pipiens, although both species were capable of transmitting the parasite by natural feeding. Oocysts developed and sporozoites also were produced in C. restuans, but its ability to transmit the parasite was not determined. Aedes aegypti (Rockefeller strain) and A. triseriatus were refractive to P. kempi. Plasmodium kempi produces trophozoites with large refractile globules and fine cytoplasmic extensions, mature schizonts in the form of a condensed fan containing four to eight nuclei (usually 5), and elongate gametocytes with irregular borders. All stages are confined almost exclusively to mature erythrocytes, with no effect on host cell size or position of host cell nucleus. Plasmodium kempi is most similar morphologically to P. (Novyella) hexamerium and P. (Novyella) vaughani. It differs from P. hexamerium in having large refractile globules in trophozoites and immature schizonts, an inability to infect starlings, an absence of phanerozoites in capillary endothelium of the brain, and the ability to develop in C. pipiens mosquitoes. Plasmodium kempi is more like P. vaughani morphologically, but differs by infecting turkeys and ducks (transient), by its inability to infect starlings, its lack of morphological variation even when in different hosts, and its ability to develop in C. pipiens and C. tarsalis.
本文介绍了疟原虫（新疟原虫属）肯氏疟原虫的脊椎动物宿主特异性、实验室内的传播媒介，以及来自爱荷华州东部野生火鸡（Meleagris gallopavo silvestris Vieillot）的该疟原虫新种。肯氏疟原虫可感染家火鸡、北美鹑（Colinus virginianus）、石鸡（Alectoris graeca）、珍珠鸡（Numida meleagris）、孔雀（Pavo cristatus）和金丝雀（Serinus canaria），能在绿头鸭（Anas platyrhynchos）和家鹅（Anser anser）中引起短暂感染，但不会感染环颈雉（Phasianus colchicus）、鸽子（Columba livia）、日本鹌鹑（Coturnix coturnix）、来航白鸡（Gallus gallus）或椋鸟（Sturnus vulgaris）。分别从68%（84/124）的致倦库蚊和98%（60/61）的骚扰库蚊中检出了卵囊和（或）子孢子。骚扰库蚊中卵囊发育更快，子孢子侵入唾液腺的时间更早（6天），而致倦库蚊中则为7天。尽管两种库蚊都能通过自然取食传播该寄生虫，但骚扰库蚊传播肯氏疟原虫的效率比致倦库蚊更高。雷氏库蚊中也能发育出卵囊并产生子孢子，但其传播该寄生虫的能力尚未确定。埃及伊蚊（洛克菲勒品系）和三带喙库蚊对肯氏疟原虫具有抗性。肯氏疟原虫产生的滋养体带有大的折光性球体和细小的细胞质延伸，成熟裂殖体呈浓缩扇形，含4至8个核（通常为5个），配子体细长，边界不规则。所有阶段几乎都仅局限于成熟红细胞内，对宿主细胞大小和宿主细胞核位置均无影响。肯氏疟原虫在形态上与六核疟原虫（新疟原虫属）和沃氏疟原虫（新疟原虫属）最为相似。它与六核疟原虫的不同之处在于，滋养体和未成熟裂殖体中有大的折光性球体，不能感染椋鸟，脑毛细血管内皮中没有显型子孢子，且能在致倦库蚊中发育。肯氏疟原虫在形态上更像沃氏疟原虫，但不同之处在于它能感染火鸡和鸭子（短暂感染），不能感染椋鸟，即使在不同宿主中也缺乏形态变异，且能在致倦库蚊和骚扰库蚊中发育。
