Identifying 3rd larval stages of common strongylid and non-strongylid nematodes (class: Nematoda) infecting Egyptian equines based on morphometric analysis.

Strongylid and non-strongylid nematodes are one of the most important parasites infecting equines. The traditional method to identify these nematodes is through coproscopy and fecal culture. Because of the scarcity of data published in Egypt discussing the morphometric features of infective 3rd larvae of these nematodes, this study aims to provide a morphometric key for L3 of common strongylid and non-strongylid nematodes infecting Egyptian equines. For this reason, we cultured fecal samples containing GINs eggs and 3rd larval stages were identified based on their morphology (i.e., shape and number of intestinal cells (IC), shape of the esophagus, and shape of the tail sheath) in addition to computing their dimensions (i.e., length of larvae with sheath, length of the esophagus, length of intestinal cells, and body breadth). We identified 3rd larval stages of four strongylid nematodes (Cyathostomum sensu lato, Strongylus vulgaris, Strongylus equinus, and Strongylus edentatus) as well as two non-strongylid nematodes (Strongyloides westeri, and Trichostrongylus axei). Statistically, our results revealed significant differences in terms of total length, body width, esophagus length, and gut length among 3rd larvae identified in the current study. The combination of both morphological and metric keys will allow the better identification of common strongylid and non-strongylid nematodes infecting equines.

A trial of doramectin injection and ivermectin spot-on for treatment of rabbits artificially infested with the ear mite "Psoroptes cuniculi".

The ear mite "Psoroptes cuniculi" is the main cause of ear mange, a highly contagious parasitic skin disease in rabbits all over the world. In the current work, a preliminary therapeutic trial to study the effect of the broad use acaricides doramectin and ivermectin on P. cuniculi was performed on artificially infested rabbits. Twenty five adult New Zealand white rabbits were used in this study. The rabbits were assigned randomly into five groups/ 5 rabbits in each group. Each rabbit was experimentally infested with 100 mites/ ear. The first group was designated the positive control group and was not treated. The second and third groups were treated with doramectin 200 and 400 µg/kg bw, respectively. Groups 4 and 5 were treated by dressing with ivermectin in one dose and 2 doses with a 1 week interval. After the therapy, all rabbits were examined microscopically on the 7th, 14th, and 28th day post treatment and the number of live mites (larvae, nymphs, and adults) on each rabbit was counted at the end of the experiment (28th day). The results showed that the rabbits treated subcutaneously with doramectin at a single dose of 200 µg /kg bw showed a very low effect, although there was significant improvement when the dose was doubled to 400 µg /kg bw, with the number of mites counted decreasing significantly. Rabbits treated topically with ivermectin spot-on, a single dose or 2 doses, showed great improvement of the lesion: the number of mites was reduced to zero. In conclusion, this work showed that ivermectin spot-on applied locally on infested ears proves to be more effective against P. cuniculi than doramectin injected subcutaneously. Further trials on ear mange therapeutics in rabbits are to be encouraged.

Observations of the rabbit pinworm Passalurus ambiguus (Rudolphi, 1819) in domestic rabbits (Oryctolagus cuniculus) in Egypt using a scanning electron microscope.

Passalurus ambiguus (Rudolphi, 1819) is one of the most common oxyurid nematodes to be found in domestic and wild rabbits worldwide. In order to identify and determine the morphological characteristics of this pinworm, the current research was conducted as a microscopic study, using a scanning electron microscope (SEM). Adult P. ambiguus were collected from naturally infected domestic rabbits in Egypt. Identification was made primarily by ordinary microscope, and subsequently, the morphological features were evaluated by SEM. Results indicate that SEM is a powerful tool to identify in detail the morphological characteristics such as the head, male cloacal area, female tail and the female copulatory plugs. All these features confirm the species is P. ambiguus and show the effectiveness of the SEM to differentiate P. ambiguus from related oxyurid species.