News from XYOM

Last changes in XYOM

  • June 2020 Version II of XYOM is coming soon, more friendly and complete, less demanding to the user, etc.
  • March 2020 Plotly not allowing the easy access it provided before. Next XYOM version will provide some editing tools.
  • 24/02//2019 CLASSIFICATION, input variables = distances, analysis = HC: it is now open again to enter the names of the OTUs to build a tree.
  • 24/02//2019 MISCELLANEOUS, WORKING WITH FILES, CONCATENATION: the output format has been improved (the first row – the comment – is now fixed to be just one row).

Contribution of geometric morphometry in the control of Rhipicephalus (Boophilus) microplus (Canestrini, 1888) on the transhumance corridor between Côte d’Ivoire and Burkina Faso

Int. J. Biol. Chem. Sci. 11(6): 2630-2648, 2017

 

Amenan Claude Aimée DIAHA-KOUAME 1* , Tah Yves Nathan TIAN-BI 2 ,
Kouassi Patrick YAO 3 , Yaba Louise ACHI 4 , Marlène DUPRAZ 5 , Koffi KOUAKOU 1 et Jean-Pierre DUJARDIN 6
1
Laboratoire de Biologie de la Reproduction et d’Endocrinologie,
Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire.
2
Laboratoire de Génétique, Unité de Formation et de Recherche Biosciences,
Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire.
3
Laboratoire de Zoologie et Biologie Animale URF de Parasitologie et Ecologie Parasitaire,
Université Félix Houphouët-Boigny, Côte d’Ivoire.
4
Institut National de la Formation Professionnelle Agricole (INFPA), Ecole de Spécialisation en Elevage et de
Métiers de la Viande de Bingerville (ESEMVB), Côte d’Ivoire.
5
MIVEGEC UMR 5290 CNRS-IRD-UM, Centre IRD, 911 Avenue Agropolis,
BP 64501, 34394 Montpellier, France.
6
IRD, UMR IRD-CIRAD INTERTRYP, Campus International de Baillarguet, Montpellier, France.

 

ABSTRACT

Rhipicephalus (Boophilus) microplus is a tick characterized by its resistance to most acaricides currently used. Selection tools for control or eradication strategies to achieve sustainable results are still poorly accessible. In entomology, as well as in many other research fields involving arthropod studies, the study of shape variation has proven useful for species identification and population characterization. Thus, in our study,
we studied the morphological diversity of R. (B.) microplus using two methods of morphometry: classical morphometry (MC) and geometric morphometry (MG) on ticks collected in ten farms from two axes of the Ivoiro-Burkinabé transhumance corridor. The analysis of the results showed a morphological heterogeneity according to the  geographical position of the populations studied on the two axes. Both methods showed
similar results but the geometric morphometry presented itself as an interesting approach because it allows to visualize the differences of form between groups or between individuals. We have thus shown to what extent these two approaches can help to understand the epidemiology, the structure and the mobility of tick populations at a lower cost and consequently, to contribute to the improvement and the sustainability of the regional control activities.

 

The modern morphometric approach to identify eggs of Triatominae

Soledad Santillán-Guayasamín 1 , Anita G. Villacís 1 , Mario J. Grijalva 1,2* and Jean-Pierre Dujardin 1,3

1

Center for Research on Health in Latin America (CISeAL), School of
Biological Sciences, Pontifical Catholic University of Ecuador, Av. 12 de
Octubre 1076 y Roca, Quito, Ecuador

2

Infectious and Tropical Disease Institute, Department of Biomedical
Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens,
OH 45701, USA

3

IRD, UMR 177 IRD-CIRAD INTERTRYP, Campus international de Baillarguet, Montpellier, France.

 

Parasites & Vectors (2017) 10:55
DOI 10.1186/s13071-017-1982-2

 

Abstract
Background: Egg morphometrics in the Triatominae has proved to be informative for distinguishing tribes or genera, and has been based generally on traditional morphometrics. However, more resolution is required, allowing species or even population recognition, because the presence of eggs in the domicile could be related to the species ability to colonize human dwellings, suggesting its importance as a vector.
Results: We explored the resolution of modern morphometric methods to distinguish not only tribes and genera, but also species or geographic populations in some important Triatominae. Four species were considered, representing two tribes and three genera: Panstrongylus chinai and P. howardi, Triatoma carrioni and Rhodnius ecuadoriensis. Within R. ecuadoriensis, two geographical populations of Ecuador were compared. For these comparisons, we selected the most suitable day of egg development, as well as the possible best position of the egg for data capture. The shape of the eggs in the Triatominae does not offer true anatomical landmarks as the ones used in landmark-based morphometrics, except for the egg cap, especially in eggs with an evident “neck”, such as those of the Rhodniini. To capture the operculum shape variation, we used the landmark- and semilandmark-based method. The results obtained from the metric properties of the operculum were compared with the ones provided by the simple contour of the whole egg, as analyzed by the Elliptic Fourier Analysis. Clear differences could be disclosed between the genera, between the species – among which two very close species (P. chinai and P. howardi), as well as between two allopatric, conspecific
populations. The whole egg contour (including the operculum) produced reclassification scores much more satisfactory than the ones obtained using the operculum only.
Conclusions: We propose the outline-based approach as the most convenient  characterization tool to identify unknown eggs at the species or population levels.

The wing venation patterns to identify single tsetse flies

D. Kaba a , D. Berté a , B.T.D. Ta a , J. Tellería b , P. Solano b , J.-P. Dujardin b, *
a
b
INSP/IPR Bouaké, Côte d’Ivoire
UMR 177, INTERTRYP, CIRAD-IRD, Baillarguet, France

Infection, Genetics and Evolution 47 (2017) 132–139

A B S T R A C T
This is the first study to explore the potential of various geometric morphometrics methods to help the morphological diagnostic of tsetse species, vectors of human and animal trypanosomiases in sub-Saharan Africa. We compared landmarks, semilandmarks and outlines techniques on male and female samples of species, and suggested adapted strategies according to the countries and their own Glossina fauna. We could compare up to 7 taxa belonging to the three main subgenera of the Glossina genus: Nemorhina (5 species), Glossina (1 species) and Austenina (1 species). Our sample included the major vectors of sleeping sickness:
G. palpalis palpalis, G. p. gambiensis, G. fuscipes fuscipes and G. f. quanzensis, as well as two important vectors of African animal trypanosomoses: G. tachinoides and Glossina morsitans submorsitans. The average level of correct species recognition by the wing shape was satisfactory, and slightly higher for females than for
males. The best scores of correct assignment, in both sexes, were obtained by the contour technique (96% of correct attribution in females, 92% in males), slightly higher than for semilandmarks (95% and 91%) or landmarks (94% and 89%) techniques. We made our images of wings freely available to be used as reference images (http://mome-clic.com), and we describe the conditions and the analytical steps to be followed to identify unknown specimens using external reference images. Under adequate conditions, such use of reference images obtained from a free access server could help species identification of new samples anywhere in Africa.