Parasitic Nematode Infective Larvae (L3): “Heads + Tails” - Small Ruminants + Cattle
1
2
J.A. van Wyk and E. Mayhew
1
Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, 0110 Onderstepoort, South Africa. <[email protected]>
2
Department for Education Innovation, University of Pretoria
± 33µm
No filament
X
Trichostrongylus
colubriformis
± 50µm
No filament
± 1.7 X
Trichostrongylus
falculatus/rugatus
± 35µm
± 1.2 X
Teladorsagia
circumcincta
(18 - 22 intestinal cells)
Tip blunter
± 20 - 25%
± 45µm
± 1.5 X
Cooperia
curticei
Oesophagostomum
columbianum
No filament
Tip finer
± 20%
± 75µm
± 2.4 X
Cooperia
oncophora
Tip blunter
± 10-15%
± 75µm
± 2.5 X
Haemonchus
contortus
Chabertia ovina
(28 - 32 intestinal cells)
± 50%
± 130µm
Gaigeria
pachyscelis/
Bunostomum
trigonocephalum
± 4.4 X
± 25%
± 125µm
± 4.1 X
Chabertia
ovina
± 60-70%
± 155µm
Oesophagostomum
columbianum
± 5.1 X
0
50
25
100
75
150
125
Cranial and caudial extremities of third-stage larvae of common nematodes of small ruminants, measured in micrometres (µm)
No sheath tail
Tip unevenly blunt
Strongyloides
papillosus
± 33µm
No filament
X
Trichostrongylus
axei
± 65µm
No filament
± 2.2 X
Ostertagia
ostertagi
Tip blunter
± 20%
± 60µm
± 2.0 X
Cooperia pectinata
& C. punctata
Tip very fine
± 20%
± 95µm
± 3.1 X
Cooperia
oncophora
Tip blunter
± 50%
± 75µm
± 2.4 X
Bunostomum
phlebotomum
± 20%
± 100µm
± 3.4 X
Haemonchus
placei
Tip very fine
± 25%
± 150µm
± 5.1 X
Chabertia
ovina
± 40 - 45%
± 165µm
± 5.4 X
Oesophagostomum
radiatum
0
50
25
75
100
150
125
Cranial and caudial extremities of third-stage larvae of common nematodes of cattle, measured in micrometres (µm)
± 60%
± 265µm
Nematodirus
spathiger
± 9.0 X
± 220µm
± 50%
Nematodirus
battus
± 6.7 X
b
± 50%
± 260µm
Nematodirus
filicollis
± 8.7 X
0
25
50
75
100
125
a
150
175
200
225
250
275
Cranial and caudial extremities of third-stage larvae of Nematodirus spp., measured in micrometres (µm)
c
d
Diagram of a nematode infective larva, depicting:
(a) total length, (b) tip of larva tail, (c) sheath tail
extension and (d) filament.
Acknowledgments:
UNIVERSITEIT VAN PRETORIA
UNIVERSITY OF PRETORIA
Y U N I B E S I T H I YA P R E T O R I A
Faculty of Veterinary Science
The authors are grateful for the following financial support:
(i) RED MEAT RESEARCH & DEVELOPMENT SA; (ii) Cape Wools SA; (iii) THRIP (National Research Foundation, South Africa),
(iv) BBSRC/DFID/Scottish Government [grant number BBH00940/1]
Reference:
Van Wyk, J.A., Mayhew, E., 2013. Onderstepoort J. Vet. Res., 80(1), Art. #539, 14 pages http:// dx.doi.org/10.4102/ojvr. v80i1.539; Van Wyk et al., 2004. Vet. Parasitol., 119, 277-306