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1.
The protozoan Blepharisma japonicum showed negative phototaxis caused by transient reversal of the direction of ciliary beat and changes of swimming velocity induced with varying intensities of light. The ciliary reversal occurred at 1–2 sec after a sudden increase in light intensity. When light intensity was decreased, no response was observed. Moreover, the ciliates swam fast in light areas but slowly in dark areas; the mean velocity of swimming was 80 μ m/sec at 5 × 102 lux but reached about 400 μMm/sec at 5 × 103 lux. In addition, the cell body elongated in response to light application; the mean length of the body was 308 μm at 5 × 102 lux, which increased to 397 μ m at 104 lux. Such body elongation seems to contribute to rapid swimming. Negative phototaxis may be an important behavior in B. japonicum because the organisms are killed by exposure to strong light.  相似文献   

2.
SYNOPSIS. Haemogregarina faiyumensis n. sp., a parasite of toads, Bufo regularis, in Faiyuni Province, Egypt, U.A.R., is described. In a survey of 689 toads from various localities in Cairo, Giza and Faiyurn provinces, only 3 out of 13 toads from Kom O Shim near Faiyum were infected. This species, known only by blood forms (most probably gametocytes) of two different staining reactions, is 13-17 μ long and 4-5 μ wide, with an average of 15.5 × 4.5 μ. The nucleus is typically subcircular and 3-5 × 3–5 μ, with an average of 4.5 × 3.9 μ.  相似文献   

3.
Ortholinea alata n. sp. is described from the northern butterfly fish, Chaetodon rainfordi collected at Heron Island, Great Barrier Reef, Australia. Spherical, disporous trophozoites (10–15 μ) and spores were observed in the lumina of kidney tubules and collecting ducts. Spores are broadly triangular with two short, broad processes that extend dorsoventrad from the posterior end of each of the two spore valves. Valves are bisected by a suture in the plane of the polar capsules. Spores are 12.6 μ (length) × 9.6 μ (width) × 9.9 μ (length), and at the anterior end contain two spherical, divergent polar capsules measuring 4.6 ( 4.1 –5.1) μ. Sporogenesis is similar to that of renal Sphaerospora spp.: the intraluminal trophozoites of O. alata n. sp. correspond to pseudoplasmodia described for Sphaerospora spp. and no large, multinucleate plasmodia are formed. No significant histopathological changes were observed in the kidneys of infected fish.  相似文献   

4.
SYNOPSIS. Haemogregarina boueti França, 1910, was found to be the commonest blood parasite in the common toad, Bufo regularis Reuss, in Egypt. The rate of infection was about 30% (of 689 toads examined). In properly fixed blood films, the parasites were almost exclusively intraerythrocytic. Most characteristic was the encapsulated “elongate” form averaging 22.3 by 6 μ with a more-or-less central nucleus and a pointed, slightly bent, posterior end. Infected red cells were conspicuously hypertrophied and their nuclei were markedly displaced and frequently broken into 2-4 parts. Young and growing blood forms as well as two types of hepatic schizonts are described for the first time. Schizonts of the first type develop in hepatic cells, are 28–30 μ in diameter and produce numerous elongate oval merozoites about 8 × 2.2 μ radially arranged around a residual body about 10 μ in diameter. Schizonts of the second type start their growth in erythrocytes but later complete their development as free bodies in the liver sinusoids. When mature, they are 32–35 μ in diameter and produce a larger number of thin merozoites about 8 × 1.5 μ, surrounding a larger residual body about 19 μ in diameter.  相似文献   

5.
Fifteen fecal samples from peacocks (Pavo cristatus) in Saudi Arabia contained oocysts of Eimeria riyadhae n. sp. in two peacocks and oocysts of E. arabica n. sp. in one peacock. Sporulated oocysts of Eimeria riyadhae are ellipsoidal, 27–30.5 times 20.5–25 (28.8 ± 1.3 × 22.4 ± 1.6) μm, with a two-layered wall and bilobed polar body, but without a micropyle or residuum. The sporocysts are ovoid, 11–14.5 × 6.5–8 (13.2 ± 1.2 × 7.2 ± 0.6) μm with a thick, knob-like Stieda body and a residuum. Sporulated oocysts of Eimena arabica are spheroidal, 17.5–21.5 × 17.5–21.5 (19.2 ± 1.6 × 19.2 ± 1.6) μm, with a two-layered wall and two refractile polar bodies, but without a micropyle or residuum. The sporocysts are elongate ovoid, 9.5–12 × 4–6.5 (11.2 ± 0.9 × 5.5 ± 0.88), with a small crescent-shaped Stieda body. The host bird belongs to the order Galliformis.  相似文献   

6.
ABSTRACT. Four isosporan species are described from the small tree finch, Camarhynchus parvulus from Isabela Island on the Galapagos Archipelago. Isospora exigua n. sp. oocysts subspheroidal, one-layered, smooth, yellow-brown color, 20.4 × 20.1 (20-23 × 18-23) μm, with no micropyle, residuum, or polar body. Sporocysts ovoidal, 14 × 9.5 (13-15 × 8-10) μm, with small Stieda and substieda bodies and irregular-shaped residuum. Isospora rotunda n. sp. oocysts subspheroidal, single-layered, smooth, yellow-brown wall with large polar body and no micropyle or residuum, 20.9 × 20.8 (20-24 × 19-23) μm. Sporocysts ovoidal, 15 × 9.7 (13-16 × 9-10) μm with knob-like Stieda bodies, prominent substieda bodies and round residuum. Isospora fragmenta n. sp. oocysts subspheroidal with no micropyle or residuum but with many splinter-like polar granules and a smooth, colorless, single-layered wall, 25.3 × 24.2 (24-27 × 23-25) μm. Sporocysts piriform 15.4 × 11.5 (14-17 × 11-12) μm with knob-like Stieda bodies, prominent substieda bodies, and irregular-shaped residuum. Isospora temeraria n. sp. oocysts ellipsoidal with one polar body, no micropyle or residuum, and wall of a single layer, smooth, yellow-brown color, 25.4 × 21.1 (21-30 × 17-23) μm. Sporocysts piriform, 15 × 10 (14-15 × 9-11) μm with knob-like Stieda bodies, prominent substieda bodies, and a round residuum. One woodpecker finch, Cactospiza pallida, was found to be infected with I. exigua, and a warbler finch, Certhidea olivacea was infected with I. fragmenta.  相似文献   

7.
Feces from a specimen of Tamandua tetradactyla (Linn.) from Portel, Para State, north Brazil, contained two different coccidial oocysts; one identified as Eimeria tamanduae Lainson 1968, and the other as a new species, described here as Eimeria corticulata n. sp. Oocysts of E. corticulata are ellipsoidal, 37.4 × 30.4 (31.2–43.7 × 23.7–35.0) μm, shape index (length/width) 1.2 (1.0–1.5). Oocyst wall 2.5–3.7 μm thick and composed of two layers; an outer thick, brown-yellow one with radial striations, and a thin inner smooth one: no visible micropyle. Oocyst residuum a large globule of about 10.7 × 10.3 μm, usually accompanied by a number of smaller attached globules. Sporocysts ellipsoidal, 21.0 × 11.0 (20.0–22.5 × 10.0–12.5) μm, with a conspicuous Stieda body: shape index 1.9 (1.6–2.2). Sporocyst residuum a small number of scattered granules: sporozoites 18.7 × 5.0 μm, with a large posterior refractile body. Eimeria zygodontomyis n. sp. is described in feces from Zygodontomys lasiurus (Lund) from the Serra dos Carajas, Para. Oocysts ellipsoidal to cylindrical, 16.5 × 12.0 (13.7–18.7 × 11.2–12.3) μm, shape index 1.4 (1.2–1.5). Wall colorless, smooth, single-layered and about 0.6 μm thick: no micropyle. No oocyst residuum, but a polar granule of about 1.8 × 1.0 μm is sometimes present. Sporocysts ellipsoidal, 8.4 × 5.5(7.5–8.7 × 5.0–6.2) μm, shape index 1.5 (1.4–1.7), with a thin colorless wall and a delicate Stieda body. Sporozoites enclose a compact residuum of about 2.5 × 3.7 μm.  相似文献   

8.
Eimeria tahamensis n. sp. is described from the harlequin quail (Coturnix delegorguei arabica) from Tahama, Saudi Arabia. The sporulated oocysts of E. tahamensis n. sp. are ellipsoid, 36.5–42 × 25.5–29 (41.2 ± 1.34 × 28.4 ± 0.81) μm, with a thick two-layered wall and one polar granule but without a micropyle or an oocyst residuum. The sporocysts are ovoid, 14–16 × 9–11.5 (15.3 ± 0.7 × 10.8 ± 0.64) μm, with a knob-like Stieda body and sporocyst residuum, but without a substiedal body. The sporozoites are often located transversely at the two ends of the sporocysts. The host bird belongs to the order Galliformes.  相似文献   

9.
The formed elements of the blood of L. corrianus are comprised exclusively of amoebocytes, whose total number is approximately 758 per cubic mm of blood. The blood cells are of three types, viz. acidophils, large basophils and small basophils, which are respectively 26.32%, 60.20% and 13.48% of the total blood cell population. The cytoplasm of the acidophils is filled with large acidophilic granules, while that of the basophils contains fine basophilic granules. Acidophils are the largest (7.6 μ × 6.7 μ), large basophils are smaller (6.5 μ × 4.9 μ), and small basophils are the smallest (4.1 μ × 3.8 μ). The nucleus occupies a very small volume of the cell (approx. 1/9th) in acidophils, a larger volume (approx. 1/4th) in large basophils, and a major volume (approx. 3/4th) in small basophils. The blood cells show amoeboid movement, which is brought about by means of broad lamellate pseudopodia. Large basophils move very slowly, acidophils move faster, and small basophils move quite fast. Fine bristle-like filipodia help the blood cells in getting entangled to form clumps. Filipodia are more abundant in large basophils and acidophils which pertake more actively in clumping than small basophils which rarely possess filipodia. Clumping is a reversible process which is promoted by mechanical agitation of blood.  相似文献   

10.
SYNOPSIS. Eimeria vermiformis sp. n. and E. papillata sp. n. are described from the mouse Mus musculus. The sporulated oocysts of E. vermiformis are 18–26 by 15–21 μ (mean 23.1 by 18.4 μ); its sporocysts are 11–14 by 6–10 μ (mean 12.8 by 7.9 p). The sporulated oocysts of E. papillata are 18–26 by 16–24 μ (mean 22.4 by 19.2 μ); its sporocysts are 10–13 by 6–9 μ (mean 11.2 by 8.0 μ). A substiedal body is present in E. papillata sporocysts. Patent infections were produced in white laboratory mice with both species. Fourteen species of Eimeria have now been described from the genus Mus.  相似文献   

11.
Oocysts of Eimeria morainensis n. sp. are described from the golden-mantled ground squirrel, Spermophilus lateralis. in Northern Colorado. The oocysts of E. morainensis are double-walled and subspherical, 20.3 × 19.8 (18.7–26.2 × 17.5–21.2) μm; and the sporocysts are ellipsoid, 12.1 × 6.9 (8.7–13.7 × 6.2–8.7) μm. Oocyst residuum and micropyle are absent, but a polar granule is present. Sporocyst residuum and Stieda body are present. Differences in oocyst characteristics provide the basis for recognition of this new species of Eimeria.  相似文献   

12.
SYNOPSIS. Eimeria eumopos n. sp. (Coccidiida, Eimeriidae) from a Colombian bat Eumops trumbulli (Chiroptera, Molossidae) is described. This is the first recorded coccidium in a bat from the western hemisphere, and the sixth bat coccidium species described to date. The unsporulated oocysts in the bat feces are 30.9–24.0 by 28.9–23.2 μ (near 28.8 × 26.1 μ). Their outstanding feature is the pronounced pitting of the thick brownish oocyst wall.  相似文献   

13.
14.
ABSTRACT. An undescribed species of aseptate gregarine, for which the name Pterospora schizosoma is proposed, occurs in the coelom of the maldanid polychaete Axiothella rubrocincta (Johnson). The body of the mature gamont is divided into two cylindrical trunks, which are joined anteriorly. Posteriorly, each trunk bifurcates twice, thereby producing four terminal branches. The length of the entire organism varies from 230–600 μm. The organism actively pumps endoplasm from one trunk to the other, and the nucleus (average = 56.2 × 25.9 μm) moves with the flowing endoplasm. In all four of the previously described species, the gamont's main trunks arise from a substantial body mass whereas in P. schizosoma the trunks make up most of the body mass. Pterospora schizosoma's oocysts possess a distinct outer and inner capsule, which contains eight tightly appressed sporozoites.  相似文献   

15.
SYNOPSIS. Oocysts and endogenous stages of new species of Eimeria and Isospora from the house lizard, Gehyra mutilata, are described. The ellipsoid to subspherical 2-layered oocysts of E. cicaki averaged 24.0 × 21.0 μm. Polar granules are present. Micropyle and oocyst residuum are absent. Ellipsoid sporocysts average 12.2 × 9.0 μm. A sporocyst residuum is present, but the Stieda body is absent. Endogenous stages are in epithelial cells of the small intestine. The subspherical single-layered oocysts of I. thavari average 23.8 × 22.8 μm. The polar granule is present; micropyle and oocyst residuum are absent. Ellipsoid sporocysts average 12.8 × 9.4 μm. Stieda body and sporocyst residuum are present. There are endogenous stages in epithelial cells of the small intestine.  相似文献   

16.
SYNOPSIS. In a survey of parasites of wild mammals of Malaysia 3 new species of Eimeria were found. Eimeria tupaiae sp. n. is described from the common tree shrew, Tupaia glis. Its ellipsoidal to spherical, 3-layered oocysts average 20 × 19 μm. A micropyle is absent; an oocyst residuum and polar granule are present. Ellipsoidal sporocysts average 11 × 7 μm. A sporocyst residuum and Stieda body are present. Eimeria ptilocerci sp. n. is described from the pen-tail tree shrew, Ptilocercus lowii. The ellipsoidal to spherical, 2-layered oocysts average 23 × 20 μm. A micropyle and oocyst residuum are absent; polar granules are present. The ellipsoidal sporocysts average 13 × 7 μm. A sporocyst residuum and Stieda body are present. Eimeria muuli sp. n. is described from the pencil-tailed tree mouse, Chiropodomys gliroides. The ellipsoidal single-layered oocysts average 25 × 19 μm. A micropyle and oocyst residuum are absent; a polar granule is present. The ellipsoidal sporocysts average 13 × 8 μm. A sporocyst residuum and Stieda body are present. In addition, new host records are reported as follows: E. miyairii Ohira from Whitehead's rat Rattus whiteheadi and the Malaysian wood rat, R. tiomanicus; E. separata Becker & Hall from Mueller's rat, R. muelleri, the chestnut rat, R. fulvescens, and the Malaysian wood rat, R. tiomanicus; E. nieschulzi Dieben from the red spiny rat, R. surifer and the chestnut rat, R. fulvescens; and E. callosciuri Colley from the grey-bellied squirrel, Callosciurus caniceps and the black-banded squirrel, C. nigrovittatus.  相似文献   

17.
SYNOPSIS. Three new species of coccidia are described from the alpaca Lama pacos from Peru. These are the first species of coccidia to be named from this host. The oocysts of Eimeria lamae n. sp. are ellipsoidal, occasionally ovoid, 30–40 by 21–30 μ (mean 35.6 by 24.5 μ) with elongate ovoid sporocysts 13–16 by 8–10 μ (mean 15.3 by 8.5 μ). The oocysts of Eimeria alpacae n. sp. are ellipsoidal, rarely ovoid, 22–26 by 18–21 μ (mean 24.1 by 19.6 μ), with ovoid sporocysts 10–13 by 7–8 μ (mean 11.0 by 6.8 μ). The oocysts of Eimeria punoensis n. sp. are ellipsoidal, occasionally ovoid, 17–22 by 14–18 μ (mean 19.9 by 16.4 μ), with ovoid sporocysts 8–11 by 5–7 μ (mean 9.2 by 6.1 μ).  相似文献   

18.
Morphology and recordings of electrical activity of Kuruma shrimp (Penaeus japonicus) giant medullated nerve fibers were carried out. A pair of giant fibers with external diameter of about 120 μ and 10 μ in myelin thickness were found in the ventral nerve cord. The diameter of the axon is about 10 μ. Thus there is a wide gap between the axon and the external myelin sheath. Each axon is doubly coated directly by Schwann cells and indirectly by the myelin sheath layer which is produced by those Schwann cells. Impulse conduction velocities of these giant fibers showed a range between 90–210 m/sec at about 22°C. Large action potentials (up to 113 mV, rise time of 0.16–0.3 msec, maximum rate of rise of 650–1250 V/sec, half decay time of 0.2–0.3 msec, maximum rate of fall of 250–450 V/sec and total duration of less than 1.5 msec) could be obtained by inserting microelectrodes or by longitudinal insertion of 25 μ diameter capillary electrodes into the gap but no DC-potential difference was observed across the myelin sheath. Transmyelin electrical parameters were very favorable for fast impulse conduction: myelin resistance of 3 × 104 Ω cm2; time constant of 0.38 msec; myelin capacitance of 1.35 × 10?8 F/cm2; gap fluid resistivity of 23 Ω cm. The existence of nodes of Ranvier could not be demonstrated morphologically, but electrophysiological evidence suggests that a type of saltatory conduction occurs in these giant fibers.  相似文献   

19.
ABSTRACT. Moles from England were examined for coccidian oocysts and all 64 Talpa europaea were infected; of 64 infected hosts, 56 (88%) had multiple infections representing two to six coccidian species when examined. Oocysts in 31 of the 64 samples remained unsporulated. Three eimerians and one isosporan were studied from the 33 fecal samples that had sporulated oocysts and these are described as new species; Cyclospora talpae Pellérdy & Tanyi, 1968, and Isospora sofiae (Golemansky, 1978) Levine & Ivens, 1979, are redescribed; and Cyclospora sp., similar to C. talpae, is discussed. Sporulated oocysts of C. talpae are ellipsoidal, 14.3 × 9.6 (12–19 × 6–13) μm with sporocysts ovoid, 9.4 × 5.7 (6–13 × 4–8) μm; it was found in 21 of the 33 (63.6%) sporulated samples. Sporulated oocysts of Cyclospora sp. are subspheroidal to ellipsoidal, 12.5 × 8.9 (10–14 × 6–12) μm with sporocysts ovoid, 8.6 × 5.3 (6–10 × 4–6) μm; it was found in 21 of the 33 (63.6%) sporulated samples. Sporulated oocysts of Eimeria avonensis n. sp. are elongate-ellipsoidal, 15.0 × 9.6 (13–20 × 7–12) μm with sporocysts ovoid, 6.6 × 3.6 (5–9 × 3–7) μm; it was found in 15 of the 33 (45.5%) sporulated samples. Sporulated oocysts of Eimeria berea n. sp. are subspheroidal, 12.1 × 10.5 (10–15 × 8–14) μm with sporocysts ovoid, 6.3 × 3.9 (5–10 × 2–5) μm; it was found in 8 of the 33 (24.2%) sporulated samples. Sporulated oocysts of Eimeria globula n. sp. are spheroidal, 20.9 × 19.9 (19–24 × 17–21) μm with sporocysts elongate-ovoid, 11.5 × 6.9 (9–16 × 6–9) μm; it was found in 3 of the 33 (9.1%) sporulated samples. Sporulated oocysts of Isospora sporopointaea n. sp. are subellipsoidal to ellipsoidal, 17.1 × 11.4 (13–21 × 8–14) μm with sporocysts ellipsoidal with both ends pointed, 11.9 × 5.9 (9–16 × 4–8) μm; it was found in 27 of the 33 (81.8%) sporulated samples. Sporulated oocysts of I. sofiae are spheroidal to subspheroidal, 12.2 × 11.0 (9–16 × 8–15) μm with sporocysts ovoid, 9.1 × 5.2 (6–13 × 3–8) μm; it was found in 25 of the 33 (75.8%) sporulated samples. To date, the coccidian parasites of talpids include two cyclosporans, 12 eimerians, and six isosporans, exclusive of the four new species described here.  相似文献   

20.
Fusarium moniliforme was grown on a carob aqueous extract in a chemostat for fungal protein production. The substrate was adjusted to provide 0.5% carob sugars supplemented with inorganic salts. The dilution rate varied from 0.086 to 0.227 hr?1 under constant conditions of temperature (30°C), pH (4.5), and oxygen saturation (60–80%). A yield of 0.709 g dry mycelium/g consumed carob sugar and a productivity value of 0.687 g dry mycelium/liter hr?1 were obtained at μ = 0.205 hr?1. The maintenance coefficient was 0.077 g carob sugar/g dry mycelium hr?1. While the carbohydrate and purine content of dry mycelium increased at μ values from 0.114 to 0.205 hr?1 both true (Lowry) and crude (N × 6.25) protein contents decreased at the same μ range. Maximum values of 36.3% true and 47.9% crude protein of dry mycelium were obtained at μ = 0.114 hr?1, whereas a minimum purine content of 99.8 μmol/g corresponding to 6.42% nucleic acids was recorded at μ = 0.086 hr?1. It was concluded that a continuous fermentation of carob aqueous extract using F. moniliforme should be operated at growth rates of approximately 0.205 hr?1 in order to maximize protein production.  相似文献   

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