A new Harposporium with triangular conidia attacking bdelloid rotifers

1991 ◽  
Vol 69 (6) ◽  
pp. 1284-1287 ◽  
Author(s):  
G. L. Barron ◽  
E. Szijarto

Harposporium trigonosporum is described as new. After ingestion by rotifers, the traingular conidia lodge any place between the mouth and the anus but most frequently in the lower gut. A filiform germination hypha develops from each corner of the conidium and penetrates through the gut wall into the body cavity of the host. The host frequently responds to this invasion by laying down deposits around the advancing germ tube that sometimes causes the germinating conidium to abort. More frequently a germination hypha breaks through the host deposits at one or more of the three points of attack and proliferates inside the body, resulting in the death of the rotifer. Key words: Harposporium, endoparasite, rotifer.

1983 ◽  
Vol 61 (7) ◽  
pp. 1875-1878
Author(s):  
G. L. Barron

Harposporium botuliforme is described as a new hyphomycete endoparasitic on bdelloid rotifers in soil. The sausage-shaped conidia are ingested by the host, pass through the mastax, and germinate in the lower gut. Filiform germ tubes penetrate the gut wall and produce beaded assimilative hyphae in the body cavity which kill and colonize the host.


Parasitology ◽  
1924 ◽  
Vol 16 (1) ◽  
pp. 111-112
Author(s):  
Edward Hindle

In December, 1922, whilst dissecting a large female example of Bufo regularis, one of my students noticed a cylindrical structure extending along the ventral region of the body-cavity. A careful examination showed that this structure consisted of an elongated sac-like diverticulum of the right lung, containing an almost full-grown specimen of a dipterous larva, which could be seen through the membraneous wall of the diverticulum. The base of the latter, in addition to its point of origin from the lung, was also connected to the dorsal surface of the liver by strands of fibrous tissue, suggesting that the growth had been in existence some considerable time in order to cause such adhesions. Posteriorly, the diverticulum hung freely in the body cavity and extended to the extreme hinder end. Its dimensions were 5·5 cm. in length, by 0·5 cm. in diameter, but tapering towards each extremity.


1962 ◽  
Vol 40 (7) ◽  
pp. 1269-1275 ◽  
Author(s):  
Joan F. Bronskill

In third and fourth instar larvae of Aedes aegypti (L.), juveniles of the rhabditoid, DD136, penetrate the blood sinus and cardial epithelium of the proventriculus to enter the body cavity of the host, where they complete their development. By 5 hours, a thick capsule developed about many of the ensheathed immature adults of DD136 within the body cavity of A. aegypti larvae. This rapid defence reaction of the mosquito to DD136, which has both a melanin and a cellular manifestation, occurs both in the exotic mosquito A. aegypti and in the two endemic species tested, Aedes stimulans (Walker) and Aedes trichurus (Dyar). The resistance of A. stimulans to an endemic rhabditoid, possibly of the Diplogasteridae, is also similar. The histological structure of the capsule is not affected during metamorphosis in A. aegypti; however, during histogenesis of adult tissue displacement and (or) distortion of some tissues and organs may be caused by the presence of the capsule within the host's body cavity. The activity of the adult A. aegypti is normal when this distortion or displacement is minor. Though usually encapsulated DD136 are retained within the body cavity of A. aegypti during metamorphosis, sometimes they are partially or completely expelled from the host's body cavity at the time of molting.


1985 ◽  
Vol 65 (2) ◽  
pp. 351-361 ◽  
Author(s):  
D. L. PATTERSON ◽  
M. A. PRICE ◽  
R. T. BERG

The effect of three types of diet on the carcass composition of 71 feedlot bulls of three biological types (Dairy Cross (DX), Hereford Cross (HX), and Beef Cross (BX)) was studied over a 2-yr period. Diets consisted of pelleted alfalfa with 0, 35 or 85% grain. Serial slaughter and carcass dissection into eight wholesale cuts and component tissues were carried out over an age range of 392–636 days. Interactions of biological type with diet-year were generally not significant for actual weight of muscle, bone and fat, or for weight of these tissues at a constant side subcutaneous fat weight of 16 kg. There were few significant effects of biological type or diet-year on the ratio of actual weight of subcutaneous to intermusclar plus body cavity fat. HX bulls had significantly less muscle and less bone than BX or DX, based on actual weights, but the rate of tissue accretion relative to side subcutaneous fat was the same for the three biological types. Animals on the lowest level of dietary energy had less weight of fat than did those on an 85% grain diet, but diet-year growth coefficients of tissue weights relative to side subcutaneous fat weight were generally homogeneous. It was concluded that effects of dietary energy were consistent over the biological types studied and for most of the wholesale cuts. Key words: Feedlot bulls, diet, biological types, tissue growth


PARADIGMI ◽  
2009 ◽  
pp. 71-83
Author(s):  
Jean-Jacques Wunenburger

- Linguistic Sedimentation, and Bodily Inscription At present, we are exposed to an excessive offer of images, which raises a problem of assimilation. Subjects are increasingly passive, in ways that can border on pathological conditions. Yet, it is not so much a question of condemning this situation as of finding a way of re-symbolizing images, saving them from mere contemplation and inserting them in a process of contextualisation. Such a process requires an understanding of the role of the body and of the incorporation of images along the lines of Bachelard's intuition of the "resisting" nature of images. This raises the possibility of an education to images suited to the present age.Key words: Alienation, Education, Embodiment, Image, Informatics, Symbolisation.Parole chiave: Alienazione, Educazione, Immagine, Incorporazione, Informatica, Simbolizzazione.


1949 ◽  
Vol 26 (1) ◽  
pp. 1-15
Author(s):  
J. D. SMYTH

1. Plerocercoid larvae of the pseudophyllidean cestode Ligula intestinalis from the body cavity of roach, were cultured in vitro at 40°C. in a variety of saline and nutrient media. About 65% of such cultures were aseptic. 2. During cultivation, larvae produced acid by-products (unidentified) and the pH fell rapidly. 3. The presence of these acid by-products slowed down development, or, if present in sufficient quantity, caused death. 4. In order to obtain development in nutrient media in a period (3 days) comparable to that required in a bird (the normal host) it was necessary to renew the medium 24-hourly. 5. 6% of the eggs produced from a worm cultured in horse serum were fertile. Fertile eggs were never obtained from larvae cultured in any other media. 6. Certain bacterial infections had no apparent detrimental effect on development, but others were toxic. 7. Some larvae underwent development in non-nutrient medium (¾ strength Locke's solution). The exact conditions under which this occurred was not determined. 8. Fragments (3 cm. long), of larvae or larvae with either scolex or posterior half removed, underwent development to the stage of oviposition in nutrient media. 9. Histochemical examination revealed that the plerocercoid larvae were almost fat-free. During cultivation, very large quantities of cytoplasmic fat were produced the quantity being proportional to the duration of cultivation. Fat was produced even under starvation conditions (i.e. during cultivation in saline) and can be considered a metabolic by-product. 10. The fresh plerocercoid contained great quantities of glycogen in the parenchyma and muscle regions. After cultivation in nutrient or saline media, considerable quantities were still present.


Author(s):  
M. Barson

Clarias gariepinus were collected from Lake Chivero, Zimbabwe, and examined for nematode parasites from November 2000 to May 2002. Of the 202 specimens collected, 42.6 % were infected with third-stage larvae of Contracaecum sp. in the body cavity. The intensity of the infection was 1-7 worms per fish (mean intensity = 2.2). Seasonal variation in the prevalence of the parasite was not obvious and there was no significant difference in the prevalence of infection between males and females (c2 = 2.228; P > 0.05). No significant relationship between host size and prevalence was established. There was also no significant relationship between intensity and the body condition factor (r = 0.11; P > 0.05). The low parasite prevalence may have been caused by the disruption of the infection cycle since piscivorous birds, which are the final hosts of the parasite, do not feed on C. gariepinus in Lake Chivero.


1998 ◽  
Vol 72 (4) ◽  
pp. 3377-3382 ◽  
Author(s):  
John W. Barrett ◽  
Andy J. Brownwright ◽  
Mark J. Primavera ◽  
Subba Reddy Palli

ABSTRACT A recombinant Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) expressing the green fluorescence protein (GFP) under the control of the AcMNPV polyhedrin promoter was constructed to study the spatial and temporal regulation of baculovirus infection in a permissive host. Larvae that ingested AcMNPV-GFP showed localized expression of GFP in the midgut epithelial cells, as well as hemocytes, at 24 h postinfection. The presence of fluorescence in these tissues indicated not only that the virus was replicating but also that the very late viral proteins were being synthesized. Secondary infection occurred within the tracheal cells throughout the body cavity, confirming earlier reports, and these foci of infection allowed entry of the virus into other tissues, such as the epidermis and the fat body.


1970 ◽  
Vol 60 (1) ◽  
pp. 33-42 ◽  
Author(s):  
D. J. Greathead

The relations of the Strepsipterous parasite Halictophagus pontifex Fox to seven species of its Cercopid (Aphrophorinae) hosts were studied at a grassland site in Uganda. Dissections of weekly samples of the Cercopids collected by sweeping showed that the duration of the life-cycle of H. pontifex is 30–40 days. The parasite is found only in adult hosts which can support as many individuals (up to 7) in Poophilus costalis (Wlk.) as can develop in the space available in the body cavity. Both the maximum number of parasites per host and the rate of parasitism are related to the volume of the host. Parasitism arrests development of the ovaries of female hosts; they may reproduce after emergence of male parasites but not after exhaustion of females because of reinfection by triungulins. Graphical and regression analysis of the population data (no. individuals/1 000 sweeps) show that, for P. costalis, parasitism by H. pontifex is density dependent and the chief regulating factor. Rainfall 58–64 days before sampling also was correlated with P. costalis density, but multiple regression analysis showed it to be insignificant.


2016 ◽  
Vol 8 (3) ◽  
pp. 281-285 ◽  
Author(s):  
Chidozie Nwabuisi OKOYE ◽  
Udensi Maduabuchi IGWEBUIKE ◽  
Anietie Francis UDOUMOH ◽  
Chinadindu Tochukwu OKEREKE

Testicular morphology and sperm motility were evaluated in cultured Clarias gariepinus (n = 25) purposively assigned to five groups according to their age. The results showed that the testes were paired, elongated, dorso-ventrally flattened structures, situated in the caudal aspects of the body cavity. The mean length of both right and left testes increased linearly with age, being significantly (p < 0.05) higher at 6 months than at 4 and 5 months of age, and also significantly (p < 0.05) higher at 8 months than at 6 months of age, while the mean weight and organo-somatic index of the catfish testes increased linearly until 6 months of age, after which no significant (p > 0.05) increase in the testicular weight and organo-somatic index was observed. Unidirectional progressive movement of spermatozoa was detected in the milt of C. gariepinus at 6, 7 and 8 months of age, but sperm cells were non-motile at 4 and 5 months of age. Histological sections showed seminiferous lobules, whose germinal epithelia were characterized by many cysts enclosing clones of sperm cells. Each cyst enclosed a clone of sperm cells at an identical stage of spermatogenesis. Spermatids and spermatozoa were present in the lumen of the seminiferous lobule. The obtained results indicate that the morphology of the testes of C. gariepinus is similar to the testes of members of the order Siluriformes, but sexual maturity and production of motile spermatozoa may be achieved at 6 months of age in the African catfish.


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