Some larval morphological characteristics of Camelostrongylus mentulatus and Nematodirus spathiger

A Saidi,F Hamadi,R Mimouni,W Oubrou

doi:10.32718/ujvas3-2.02

Abstract

Monitoring of gastrointestinal nematode parasites in ruminants (domestic and wild) is often based on fecal examination techniques, looking for excreted eggs and larval forms using morphological keys. These, are more available in domestic ruminants, in which helminths are widely studied, than in wild ruminants. This study tried to provide certain morphological elements that will help to recognize the L3 larvae of Camelostrongylus mentulatus and Nematodirus spathiger that could parasite either domestic or wild ruminants. For that, we resorted first to the culture of L3 larvae from fecal samples taken from African antelopes, and second by the microscopic characterization of each isolated larval morphological pattern previously identified by sequencing of its internal transcribed spacer (ITS-2) regions of the ribosomal DNA. The results of different microscopic captured images showed that Camelostrongylus mentulatus larva is 16 intestinal cells that measuring approximately 820 µm length, ‎≈ 25 µm wide, and ‎≈ 47 µm for its sheath tail extension and by this be closer to Teladorsagia circumcincta characteristics. For Nematodirus spathiger, it possesses 8 gut cells and measuring about 1020 µm long, ‎≈ 25 µm wide, and‎ ≈ 143 µm for its sheath tail extension with specific tail appendages. Have done this, we were able to get some clarifications on the morphology of the studied larvae, and we believe thus that this study will contribute to the establishment of morphological identification keys especially for parasitic nematodes of wild ruminants.

Highlights

Gastrointestinal nematodes are common parasites of a wide range of mammals, especially herbivores
The parasitic phase during which the adult nematode is generally located in the digestive tract lumen of the parasitized host, where the female nematode lays eggs that will be excreted in the environment through the feces
Ruminants are subject to such parasitic infections, especially when they are sequestered in limited space pasture dimensions that are continuously contaminated by L.3 infective larvae (Molento et al, 2016)

Summary

Introduction

Gastrointestinal nematodes are common parasites of a wide range of mammals, especially herbivores. They have a direct cycle with two phases: parasitic phase and free-living phase. The freeliving phase takes place outside the animal, which starts with the hatching of eggs producing first stage larva that will molt to the second the third-stage larva (L.3). This latter is the infective stage that will infect the host by oral route in the pasture when grazing and will molt inside the animal to the fourth the fifth stage larva before becoming adult nematode (Anderson, 2000). The problem presents itself even more pointedly when dealing with threatened species, in which we cannot tolerate such health disorders, and we are forced to adopt an ecologically adequate sustainable health management strategy combining diseases control and biodiversity preservation (Aguirre et al, 2002; Delahay et al, 2009)

Methods

Results

Conclusion