Scanning Electron Microscopy of the Sheathed Infective Larva and Parasitic Third-Stage Larva of Haemonchus contortus (Nematoda: Trichostrongyloidea)

1990 ◽  
Vol 76 (2) ◽  
pp. 248 ◽  
Author(s):  
J. R. Lichtenfels ◽  
H. R. Gamble ◽  
J. P. Purcell
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Haemonchus Contortus ◽  
Infective Larva ◽  
Stage Larva ◽  
Third Stage ◽  
Scanning Electron

Scanning electron microscopy of different vulval structures in a Mexican Haemonchus contortus isolate

2021 ◽  
pp. 100640
Author(s):  
Cintli Martínez-Ortiz-de-Montellano ◽  
Juan Felipe de Jesús Torres-Acosta ◽  
Carlos Alfredo Sandoval-Castro ◽  
Isabelle Fourquaux ◽  
Hervé Hoste
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Haemonchus Contortus ◽  
Scanning Electron

scholarly journals Nematicidal Effect and Histological Modifications Induced by Hydrolysable Tannin Extract on the Third-Stage Infective Larvae of Haemonchus contortus

Biology ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 442
Author(s):  
Perla María del Carmen Acevedo-Ramírez ◽  
Claudia Hallal-Calleros ◽  
Iván Flores-Pérez ◽  
Fernando Alba-Hurtado ◽  
María Berenit Mendoza-Garfias ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Haemonchus Contortus ◽  
Effective Control ◽  
Tannin Extract ◽  
Physical Damage ◽  
Hydrolysable Tannin ◽  
Green Production ◽  
Scanning Electron

Haemonchus contortus is the most frequent and most important nematode parasite in the ruminants production of tropical and subtropical regions. There are strains resistant to all families of available anthelmintics. Consequently, the conduction of research to find other resources that allow effective control of this parasitic disease, preferably focusing on green production, is necessary. The aim of this study was to evaluate the effect of hydrolysable tannin extract (HTE) on larvae 3 (L3) of H. contortus in vitro. L3 were exposed to different HTE concentrations and times. In addition, both light and scanning electron microscopy were used to explore physical damage on L3 subjected to HTE activity. After 72 h of incubation, the mean lethal concentration of HTE was 2 mg/mL; this concentration has been previously referred to as safe for consumption in cattle. Scanning electron microscopy revealed H. contortus L3 destruction, damage was evident by separation of the sheath mainly in the cervical and caudal regions of the larva and by rupture of the cuticle with larval evisceration. Our results suggest that hydrolysable tannin extract from chestnut could be considered as a green alternative for parasitic control in ruminants.

Nematodirus battus: scanning electron microscope studies of the duodenal mucosa of infected lambs

Parasitology ◽  
1980 ◽  
Vol 81 (3) ◽  
pp. 573-578 ◽  
Author(s):  
Jean Martin ◽  
D. L. Lee
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Goblet Cells ◽  
Duodenal Mucosa ◽  
Intestinal Damage ◽  
Third Stage ◽  
Scanning Electron

SUMMARYLambs given 60000 third-stage larvae of Nematodirus battus were killed on days 16, 20, 22, 24 and 32 of the infection and the duodenal mucosa was examined by scanning electron microscopy (SEM). On day 16 of the infection the villi were long and finger-like and, although goblet cells were visible, the surface of the villi was not extensively folded, as is the surface of villi of uninfected control animals. By day 20 of the infection the villi had been reduced to flattened, plate-like structures or had formed low, irregular-shaped ridges. On this day of the infection the nematodes appeared to be enclosed by mucus-like material. As the infection progressed the intestinal damage was repaired, so that, by day 24 of the infection, the surface of the intestine was covered by short, smooth, finger-like projections and, by day 32 of the infection, the morphology of the intestine was somewhat similar to that of the control lamb. The possible role of villus atrophy and of mucus in the rejection of N. battus from the intestine is discussed.

Scanning electron microscopy of Haemonchus contortus exposed to tannin-rich plants under in vivo and in vitro conditions

2013 ◽  
Vol 133 (3) ◽  
pp. 281-286 ◽  
Author(s):  
C. Martínez-Ortíz-de-Montellano ◽  
C. Arroyo-López ◽  
I. Fourquaux ◽  
J.F.J. Torres-Acosta ◽  
C.A. Sandoval-Castro ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Haemonchus Contortus ◽  
Scanning Electron

Preparasitic Moults in Nippostrongylus Muris, with Remarks on the Structure of the Cuticula of Trichostrongyles

Parasitology ◽  
1936 ◽  
Vol 28 (2) ◽  
pp. 161-171 ◽  
Author(s):  
John T. Lucker
Keyword(s):  
Comparative Study ◽  
Haemonchus Contortus ◽  
Infective Larva ◽  
The Body ◽  
Body Tissue ◽  
Stage Larva ◽  
Tail Region ◽  
Early Separation ◽  
Second Stage ◽  
Third Stage

Rhabditiform first-stage larvae of Nippostrongylus muris are about 270–550μ long. The development of these larvae culminates in a moult, which occurred 36–48 hours after cultures were prepared. The first moult is preceded by an unusually early separation of the first cuticle, which is fine and unstriated, from the body tissue in the tail region and, later, by the formation of an underlying new cuticle, which is thicker and prominently striated.Early second-stage rhabditiform larvae differ in certain morphological respects from first-stage larvae. Second-stage larvae are about 470–750μ long.A second preparasitic ecdysis occurs and the infective larva is a true third-stage larva. This moult was the only one previously known to occur during the preparasitic development of N. muris.The post-cervical cuticular inflation in N. muris is regarded, on the basis of a comparative study of the cuticle of this species and of Haemonchus contortus and other trichostrongyles, as resulting from the separation of the second and third layers of the cuticle. Yokogawa's view that Nippostrongylus muris has two cuticulae is rejected. N. muris has a single cuticula, apparently made up of four layers.N. muris undergoes four complete moults and the development of this species does not differ in any essential respect from that reported for other strongyles.

Embryogenesis and the first-stage larva of Thelazia lacrymalis

2003 ◽  
Vol 77 (3) ◽  
pp. 227-233 ◽  
Author(s):  
H. Dongus ◽  
P. Beelitz ◽  
H. Schöl
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Reproductive System ◽  
Distal Part ◽  
Developmental Stages ◽  
Nematode Species ◽  
Stage Larva ◽  
Female Reproductive System ◽  
Egg Membrane ◽  
Scanning Electron

AbstractThe female reproductive system of Thelazia lacrymalis (Nematoda: Thelaziidae) was investigated by light and scanning electron microscopy (SEM) with regard to the developmental stages and the stage deposited by the gravid nematode. Female T. lacrymalis have a didelphic and opisthodelphic type of reproductive system with paired ovaries, oviducts and uteri and a single vagina and vulva. Round and spindle-shaped primary oocytes are documented within the ovaries and oviducts, respectively. The distal part of each uterus provides a fertilization chamber filled with spermatozoa, followed by a sphincter-like part. Further anterior, the uteri broaden gradually containing dividing zygotes, small and large morulae, tadpole-stage embryos and horseshoe-shaped embryos which increase in length and become slimmer forming pretzel-stage embryos and larvae rolled up. The larvae stretch gradually and finally lie straight but still covered with their egg membrane in the vagina. The egg membrane encloses the whole larva and is enlarged at the pointed tail of the larva forming a bulb. At the SEM level, the first-stage larva is shown to have a terminal mouth and three hooks directed posteriorly and a striated cuticle. As morphologically identical larvae were also found in lavages of the conjunctival sac of horses infected with T. lacrymalis, this nematode species can be described as ovoviviparous.

Scanning electron microscopy of biopsy specimens removed by a colonoscope from the abomasum of sheep infected with Haemonchus contortus

Parasitology ◽  
1985 ◽  
Vol 90 (2) ◽  
pp. 357-363 ◽  
Author(s):  
C. D. Nicholls ◽  
D. L. Lee ◽  
M. J. Sharpe
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Haemonchus Contortus ◽  
Parasitic Nematodes ◽  
Fibre Optic ◽  
Biopsy Specimens ◽  
Optic Endoscopy ◽  
Surrounding Areas ◽  
Scanning Electron

The abomasum of living sheep infected with 50000 larvae of Haemonchus contortus was examined before and during infection, by means of fibre optic endoscopy. Biopsy specimens were removed from the abomasum of the living sheep and were examined by means of scanning electron microscopy. Changes were noted in the surface structure of the abomasum 2 days after infection and larvae were seen on, and burrowing into, the mucosa. These changes became more pronounced as the infection proceeded, especially after day 10 of the infection when the adult worms had appeared. The behaviour of adult nematodes was observed within the abomasum and on occasions they were seen to move from surrounding areas into an area of haemorrhage, caused by removal of a biopsy specimen. Individual nematodes were removed from the abomasum by means of the biopsy forceps. Fibre optic endoscopy was shown to be a useful tool in the study of parasitic nematodes in vivo.

Sign in / Sign up

Export Citation Format

Share Document