Trichuris Species Research Articles

Trichuris Eggs in Animal Coprolites Dated from 30,000 Years Ago

Trichuris eggs were found in Kerodon rupestris (Rodentia, Caviidae) coprolites collected in archaeological layers dated from 30,000 yr BP (before present) to 8,450 yr BP. Adult worms and eggs of this genus were not found in a search of living mammals of the region. Results indicate that K. rupestris was a host for an unknown Trichuris species not found in this rodent presently. Climate changes that occurred by 10,000 yr ago in the region could be the cause of its disappearance. The finding of parasites in archaeological material can show the antiquity of host-parasite relationships and parasite losses through time.

Redescription of Trichuris tenuis Chandler, 1930, from Llamas (Lama glama) in Oregon with a Key to the Species of Trichuris Present in North American Ruminants

Whipworms collected from llamas (Lama glama) in Oregon were identified as Trichuris tenuis Chandler, 1930. A redescription, based on the specimens collected from llamas and examination of the paratypes, is presented. The unique form of the cloaca in T. tenuis separates males of this species from all other species of Trichuris known to occur in ruminants. Among species of Trichuris for which adequate descriptions of the female exist, T. tenuis can be distinguished using an array of characters including an uneverted, aspinous vulva and a highly convoluted vagina with papillalike spines in the proximal one-fourth and a small egg chamber located approximately midway along its length. This constitutes only the second report of T. tenuis in North America and brings to 7 the number of species of Trichuris known to occur in sylvatic and domestic ruminants in North America.

A new species of whipworm from a south american hystricomorph rodent

A new species of whipworm, Trichuris robusti, is described from the cecum and large intestine of rodent, Ctnomys robusti, collected in northern Chile. The nematode shows close affinityto T. bradleyi and T. chilensis, both having been described from Chile but because of the possession of ceertain specific morphological chareacters, particularly the disposition of the proximal cloacal tube, could not be assigned to either of them. A key is presented to some of the Trichuris species reported from hystricomorph rodents in Chile and the biographical significance of speciation of chilean trichurids is discussed.

Endoparasites of birds of paradise in Papua New Guinea

General endoparasitiasis in 16 species of captive birds of paradise (BOP) in Papua New Guinea ranged from 60.0 to 79.6% during 1977, 1978, 1981, 1983 and 1984. Percent prevalence of the three major groups of parasites during thefive survey years was as follows: haematozoa, 36.7–53.0%; coccidia, 42.2–63.3% and helminths, 35.6–67.3%. Percent prevalence of blood parasites in the years 1977 and 1984 was: Haemoproteus 14.3, 20.0; Plasmodium 10.2, 4.5; Haemoproteus or Plasmodium 18.4, 8.9; Leucocytozoon 6.1, 6.7; Trypanosoma 8.2, 6.7; microfilaria 10.2, 4.5. Oocysts of Eimeria paradisaeai, Isospora raggianai and I. volki were common, as were oocysts morphologically distinct from these three species. The most frequently observed cestode eggs belonged to Raillietina and Biuterina species. Eggs of Strongyloides, Capillaria, Syngamus and Trichuris species of nematodes were also recovered. The Magnifident Bird of Paradise ( Diphyllodes magnificus) had the highest mean eggs per gram (EPG) during the five survey years, except in 1978 when the highest mean was recorded from the Lesser Bird of Paradise ( Paradisaea minor). Highest mean oocysts per gram (OPG) for the first 3 years were also recorded from D. magnificus, but Paradisaea raggiana had the highest mean OPG in 1983 and 1984. Possible causes for the greatest prevalence of endoparasites in the birds during 1977 and 1984, despite their having been regularly treated prophylactically, are considered.

Whipworms and Intestinal Threadworms

Whipworms (genus Trichuris) parasitize the lower bowel of humans, domestic animals, and wild animals. The species of Trichuris that are important in small animal practice are T. vulpis in the dog and T. campanula and T. serrata in the cat. Intestinal threadworms (Strongyloides stercoralis in the dog and S. tumefaciens in the cat) parasitize the small intestine. The identification of whipworms and threadworms, their life cycles, and the diagnosis, treatment, and control of infection are discussed in this article.

The Helminth Fauna of Chile. X. A New Species of Whipworm from a Chilean Rodent

Trichuris fulvi n. sp. is described from a Chilean rodent Ctenomys fulvus phillipiensis. The new species differs primarily from T. bradleyi and T. chilensis, two other species described from rodents in Chile, primarily in the presence of a distinct spicular sac. The nematode genus Trichuris was proposed by Roederer in 1791 for whipworms occurring in humans; i.e., Trichuris trichiura (Linnaeus, 1771). Subsequently, most terrestrial host groups have been shown to harbor one or more species of the genus. The diversity of species in cricetid and heteromyid rodents was pointed out by Chandler (1945, 1946), and Tiner (1950) presented a key to eight trichurid species occurring in rodents and lagomorphs of North America. In Chile, some of the whipworms occurring in rodents of this geographic region appear not only to be new species, but may represent a new subgenus of Trichuris (see Babero et al., 1975, 1976). MATERIALS AND METHODS Through the courtesy of Mr. Milton Gallardo, Austral University of Chile, who was working on the systematics of the host group, the writers were provided with four living specimens of Ctenomys fulvus phillipiensis, obtained from San Pedro de Atacama (Province of Tarapaca) in northern Chile. From these host specimens, a total of two male and six female trichurids were collected from the caecum. The worms were fixed in 70% ethyl alcohol and later cleared for study in lactophenol. Comparative anatomical studies of the Chilean worms with descriptions and available specimens of other species of Trichuris from rodents showed our material to represent a new species. In the description that follows, measurements, based upon all specimens collected, are in millimeters (mm) and averages are given in parentheses.

Trichuris odocoileus sp. n. (Nematoda: Trichuridae) from White-Tailed Deer, Odocoileus virginianus, in Southeastern U.S., and a Key to Trichurids in North American Ruminants

A new species of Trichuris from the cecum of white-tailed deer, Odocoileus virginianus, from the southeastern United States, is characterized herein. Males had spicules 2.20 to 3.05 mm long with bluntly rounded tips, an ejaculatory duct equal to or slightly longer than the vas deferens, and a spinous spicular sheath with an expansion near its center. Females had a spinous vulva, usually not everted, a loop in the oviduct just before it opened into the uterus, and a slightly curved posterior portion. Trichuris odocoileus was differentiated from T. lani , a species described in Russia which is most like T. odocoileus, by 1) possessing a spicular sheath with a central expansion, 2) greater size with longer ejaculatory duct and vas deferens, 3) slightly larger eggs, and 4) the unique loop in the oviduct. Trichuris odocoileus constitutes the 6th species of Trichuris recovered from North American ruminants. A key is provided to facilitate differentiation of the six species.

Structure of the Bacillary Band of Trichuris myocastoris

The presence of two cell types, hypodermal gland cells and non-glandular hypodermal cells, in the bacillary band of Trichuris myocastoris is established. The non-glandular cell component of the band is greatly reduced when compared to the structure of the bacillary band of Capillaria hepatica described previously. Beta cytomembranes occur on the pseudocoelomic side of apparently both gland and non-glandular cells. The structure of the bacillary band of trichuroid nematodes was the subject of several interpretations until electron microscope studies of this region in Capillaria hepatica by Wright (1963) and in Trichuris muris and T. vulpis by Sheffield (1963) indicated that the region is a modified hypodermal chord containing hypodermal gland cells which appear to open through a complex cuticular pore. In C. hepatica it was evident that two cell types, designated hypodermal gland cells and nonglandular hypodermal cells, occur in this region. However, in the Trichuris species studied, two cell types were not described. This note presents electron micrographs of the bacillary band of Trichuris myocastoris which clearly indicate the presence of non-glandular cells, although they are not as obvious as those in C. hepatica. MATERIALS AND METHODS Specimens of T. myocastoris were removed from the cecum of freshly killed nutria (Myocastor coypu) and fixed whole in 1.2% KMnO4 in 0.9% NaCl at ~4 C for 10 hr. The specimens were dehydrated through cold ethanol, transferred to propylene oxide, and embedded in Araldite 502. Sections stained with lead citrate (Venable and Coggshall, 1965) were examined from several levels through the esophageal region of the worms. Received for publication 23 April 1968. RESULTS AND DISCUSSION The non-glandular cells of the bacillary band of T. myocastoris are greatly reduced in number and extent when compared to those of C. hepatica, and hence are not as easily demonstrated. In this regard, permanganate fixation has been a valuable aid as it selectively stains lipoprotein membranes, thereby clearly delineating cellular limits. The marginal non-glandular cells of the lateral hypodermal chord which gave rise to the interchordal hypodermis are most clearly seen (Fig. 1). Within the bacillary band, the non-glandular cytoplasm is frequently seen only as fine processes between hypodermal gland cells. Occasionally these processes can be traced to a nuclear region within the chord (Fig. 2). The cells resemble the non-glandular cells of the bacillary band of C. hepatica in their compliment of organelles, although their glycogen content is much lower. The non-glandular cells enclose the apical ends of the gland cells so that except for a very small area of some gland cells just at the margin of the pore, the gland cell does not come into contact with cuticle. The most striking feature of non-glandular cells differing from those of C. hepatica is the presence of numerous infoldings of the basal cell membrane (p3 cytomembranes, Sj6strand, 1956)

The species of Trichuris in the domestic cat.

A species of Trichuris is described from domestic cats in the Bahama Islands, and identified as T. campanula. Previous descriptions of the two species of Trichuris in the domestic cat are summarised, and it is concluded that both are valid species.

An investigation on the life cycle of Trichuris muris.

Data concerning the life cycle of the various species of the genus Trichuris are somewhat controversial. The present paper is devoted to the study of T. muris, a common parasite of the caecum of wild house-mice and rats. The possibility of transfer of T. muris in the laboratory mice would enable the author to solve various contradictory points.

On some characters of the genus Trichuris and a description of T. parvispicularis n.sp. from a Cane rat.

The identification of the species of the genus Trichuris has been much simplified since the appearance of a paper by Chandler in 1930 in which he pointed out that the prepuce-like expansion surrounding the extruded spicule has very little diagnostic value because of its extreme variability. The length and appearance of the spicule is useful only when used in conjunction with other characters for this is a variable structure. However, the six species with which he was concerned could readily be distinguished by certain internal structures which seem to exhibit great constancy and reliability. These structures are the length of the cloacal tube and its diverticulum for the head of the spicule, the length and shape of the ejaculatory duct and the nature of the folding of the vas dcferens and of the testis. Using these characters and other minor ones, he was able to give useful descriptions of the males of Trichuris trichiura, T. vulpis, T. ovis, T. minuta and T. leporis and to describe a new species T. tenuis.

Trichuris Species from California Rodents

Specimens from Thoimomys bottae bottae are larger than those described by Hall, 1916, from Thomomys fossor in Colorado, the males measuring 28 to 30 mm in length, and the females 28 to 33 mm. In Hall's specimens, which were probably immature, the anterior portion of the body exceeded the posterior portion in length, but in my mature specimens the posterior portion equals or exceeds the anterior portion in length. The specimens agree in the bilobed end of the male body, the bell-shaped, spiny, spicular sheath, and the length of the spicule (about 1.5 mm long in my specimens). The spicule flares slightly a short distance behind the tip. The cloacal tube is about 2.5 mm long, and is joined by the spicular tube near the middle of its length. The ejaculatory duct joins the vas deferens at about the middle of the length of the posterior portion of the body. In the female the vulva is not situated on a prominence, and the ovejector is from 1.1 to 2 mm long, gradually widening into the uterus. The anus is subterminal. The eggs, not seen by Hall, are relatively broad, measuring 64 to 68 microns by 35 to 38 microns.

IV.—A new species of the Nematode genus Trichuris from Queensland

IV.—<i>A new species of the Nematode genus</i> Trichuris <i>from Queensland</i>