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The lifecycle of Brachymeria podagrica, a parasitic wasp with a worldwide distribution, was studied under laboratory conditions using the flesh fly, Sarcophaga dux, as a host. Two hundred parasite-free 3rd instars of S. dux were exposed for 24 h to 20 female B. podagrica. In daily intervals, maggots and later pupae were examined for developmental stages of the parasitoid. The whole pre-imaginal development at a temperature of 26 °C lasted 21 to 26 days. Three morphologically different instars, followed by a prepupal and a pupal stage, were described using light and scanning electron microscopy. In a second experiment with 100 3rd stage Sarcophaga larvae and 10 parasitoids, a total of 70 wasps emerged 20 to 25 days after exposure. Two fly larvae did not pupate and dried out, while 28 pupae contained a dry or caseous content, dead wasp imagos, or their larval stages. No fly imagines emerged from exposed groups, while all 100 unexposed larvae pupated and adults eclosed between day 12 and day 14 after the start of the experiment, while the imagoes of the parasitoids appeared 8 to 12 days later., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Air sac nematodes from birds are known for more than 200 years now and Filaria attenuata was the first described species from falcons, owl and corvid birds. The superficial description and the loss of the original material made F. attenuata a species inquirenda. Seurat (1915) redescribed the species with material from lanner falcon and pallid harrier from Algeria and based on this description Bain and Mawson, Rec S Aust Mus 18:265-28, (1981) created a new species, Serratospiculum seurati, by adding some, slightly divergent, measurements. The current paper is based on light and scanning electron microscopy of five male and 10 female S. seurati specimens from a Peregrine falcon that acquired the infection in Pakistan. The length of the slender male and female nematodes varied between 42-70 and 165-221 mm, respectively, spicules of unequal shape and length measured 292-325 and 638-785 μm. S. seurati was also found in Saker, Barbary and crossbreed falcons.

Domesticated Old World camels (Camelus dromedarius and Camelus bactrianus) are important for the economy of several countries in Asia, Africa, and the Arabian Peninsula, and coccidiosis is an important disease in camels. There is confusion concerning the species of coccidian parasites in camels and their life cycles. Although five species of Eimeria (E. cameli, E. rajasthani, E. dromedarii, E. bactriani, and E. pellerdyi) were named from camels, E. cameli is considered the most pathogenic. Here, development of gametogonic stages and oocysts of E. cameli are described in the lamina propria of the small intestines of naturally infected camels. Only sexual stages have been confirmed.

Oocysts of a coccidian morphologically matching features of Caryospora megafalconis Klüh, 1994 were found in fecal samples and contents of the large intestines in five wild caught Clamydotis macqueenii (Gray) and 19 captive bred C. undulata (Jaquin). Scrapings of the intestinal mucosa of necropsied birds revealed macrogamonts and unsporulated oocysts. Sporulation in a potassium dichromate solution at 26 °C was completed in 48 h. Intestinal contents and sporulated oocysts obtained from feces of infected bustards as well as sporulated oocysts of C. megafalconis and C. neofalconis Böer, 1982 from two Falco rusticolis Linnaeus and one F. peregrinus Tunstall were used for DNA sequencing of the cox1, 18S ribosomal ribonucleic acid (rRNA), and 28S rRNA genes. The phylogenetic trees for all three genes showed that sequences of the material from bustards were identical with C. megafalconis from falcons. C. neofalconis and C. daceloe Yang et al., 2014 were situated in the neighboring clades. Contrary to this, subsequent sequences of C. bigenetica Wacha and Christiansen, 1982 from rattlesakes are at a distinct distance suggesting that despite morphological similarities of the oocysts, there are differences between Caryospora species of birds and reptiles. For this reason, it might be reasonable to transfer avian Caryospora species into a new genus Avispora.

Cats are host to dipylidiid cestodes of the genera Diplopylidium, Dipylidium and Joyeuxiella. Broadline(®), a topical broad-spectrum combination parasiticide containing fipronil (8.3 % w/v), (S)-methoprene (10 % w/v), eprinomectin (0.4 % w/v) and the cestocide praziquantel (8.3 % w/v), has previously been shown to be efficacious against Dipylidium caninum and Diplopylidium spp. in cats. To evaluate its efficacy against Joyeuxiella species, a blinded clinical efficacy study was conducted according to GCP. All cats had evidence for naturally acquired dipylidiid cestode infection as confirmed by pre-treatment examination. Cats were allocated randomly to two groups of 13 cats each based on bodyweight: Control (untreated) and Broadline(®) at 0.12 mL/kg bodyweight administered once topically. Based on the comparison of helminth counts in the treated and untreated cats seven days post treatment, Broadline(®) demonstrated >99 % efficacy (p < 0.01) against mature J. fuhrmanni and J. pasqualei, with 11 and 13 of the untreated cats harbouring 1 to 102 or 2 to 95 cestodes, respectively. In addition, parasite counts indicated 95.9 % efficacy (p = 0.006) against the rictularoid nematode Pterygodermatites cahirensis.

In UAE, camel Physocephalus dromedarii was diagnosed for the first time in 2011 in dromedaries from a farm that previously had imported animals from foreign countries. The large scarab beetle, Scarabaeus cristatus, was found to be the major intermediate host for this parasite in Dubai. A total of 638 specimens of S. cristatus were collected and examined for the presence of third-stage larvae of nematode larvae at two sites in the Dubai Emirate (Emirates Industry for Camel Milk and Products and horse endurance training track) within a distance of 15 km. Third-stage larvae of P. dromedarii were detected in 94 and 97 % of beetles collected from the territory of the camel milk farm and the endurance training track, respectively. In addition to third-stage larvae, 264 beetles contained second-stage larvae. Only four beetles were infected with other than P. dromedarii larvae. The average larval burden in beetles from camel milk farm was significantly higher compared to those in beetles collected from the other site (1538 vs. 697). Comparison of larval burdens in juvenile and adult beetles collected at the camel milk farm showed a significantly higher intensity in adult specimens (501 vs. 1734) while in beetles found on the horse endurance track, larval burdens were comparable (548 vs. 858). The results suggest that S. cristatus become infected at the camel milk farm, and in search for other sources of food, they fly to places where they were found feeding on feces of other animals.

The life cycle of Physocephalus dromedarii was studied under experimental conditions. Larvae obtained from naturally infected Scarabaeus cristatus and Aphodius sp. (Coleoptera: Scarabaeidae) were measured and examined in light and scanning electron microscopy and used to infect a dromedary as final host as well as chicken, mice and a toad as possible paratenic hosts. Larvae with the same morphology and similar measurements were found in naturally infected reptiles (Trapelus flavimaculatus, Eryx jayakari, Cerastes gasperettii). Body length of examined larvae varied between 1450 and 1700 μm. Dorsal, ventral and lateral lips, peg-like papillae and amphideal pits are located on the cephalic cone. There are two asymmetrical cervical deirids, long simple lateral wings and a knob-like posterior end covered with minute spines. In the camel, patency is reached within 12 weeks after infection while larvae in paratenic hosts migrate into the wall of the alimentary tract and become dormant.

Delicate filamentous schistosomatids detected in the intestinal veins of experimentally infected chickens are here described as a new parasite species, Gigantobilharzia melanoidis, and details of its life cycle are given. It is the first complete description of a schistosome species that uses Melanoides tuberculata as an intermediate host. Apharyngeate ocellate brevifurcate cercariae found in 65 out of 950 M. tuberculata collected in a pond in Al Aweer, United Arab Emirates were used as infection material. The new species can be distinguished from the other species of the genus by the following combination of characters: caecal reunion in males situated anterior to seminal vesicle, a very short gynecophoric canal (gynecophoric canal length/body length ratio lower than 0.05) supported by 12-14 thickened bands. Cercariae of G. melanoidis can be distinguished from other Gigantobilharzia cercariae described in the literature based on the combination of these characters: flame cell formula 2[3 + 3 + (1)] = 14 and relatively longer tail stem in relation to body (tail stem length/body length ratio = 2). Under laboratory conditions at a temperature between 24 and 26 °C, M. tuberculata started to shed cercariae 7 weeks after exposure to miracidia. The prepatent period of G. melanoidis in experimentally infected chicken lasted between 43 and 49 days. The parasite inhabits the blood vessels mainly of the small intestine. Sections of adult worms and eggs were also found in histocuts of parenchymatous organs. Results of phylogenetic analysis corroborated that G. melanoidis is a distinct species; however, they also confirmed that the genus Gigantobilharzia is in need of revision and in future might be split into several genera.

Philophthalmus aweerensis, a new eye fluke species, was discovered in the conjunctival cavities of a rhea in the UAE. This fluke was described and differentiated from other eye flukes that had been found in birds in the Middle East such as Philophthalmus palpebrarum, Philophthalmus nocturnus, Philophthalmus gralli, Philophthalmus lucipetus, Philophthalmus distomatosa, and Philophthalmus hegeneri. The new species lacks spination and is characterized by a long cirrus pouch extending behind the caudal margin of the acetabulum, long vitellaria of tubular type reaching the midbody, and a genital opening situated anteriorly to the bifurcation of the caeca.

Three hundred carcasses of young goats aged between 3 and 6 months were found to be infested with cysts at routine meat inspection at an abattoir in Dubai in 2008. Two types of cestode larvae were situated in the liver, abdominal cavities, under the skin and between the fasciae of the skeletal muscles. Sixty-two typical coenuri loaded with multiple scolices (between 46 and 474) and situated in clusters (between 6 and 17) at the inner membrane of the bladder were recorded in numbers between one and 12 in 30 animals. The volume of coenuri cysts varied between one and 40 ml. The rostellum of 300-400 microm in diameter carried 26 to 32 hooks arranged in two circles. The average length of larger and smaller hooks was 160 and 114 microm, respectively. All other metacestodes were determined as Cysticercus tenuicollis. Although the structure of coenuri and the measurements of scolices were identical with Coenurus cerebralis, the location of these metacestodes outside the central nervous system, suggests that these larvae might belong to a different strain of Multiceps multiceps or even to a closely related species.

A total of 105 serum samples from endurance horses from different stables in Dubai were examined for the presence of antibodies against Theileria equi and Babesia caballi using immunofluorescence antibody test (IFAT) and competitive enzyme-linked immunosorbent assay (cELISA). A TaqMan real-time polymerase chain reaction (PCR) was used to detect DNA of piroplasms in specimens of clotted blood or EDTA blood samples of the same animals. Out of the 105 serum samples, the IFAT detected antibodies against T. equi in 35 (33.3%) cases while the cELISA gave 34 (32.4%) positive results. Eleven (10.5%) of the 105 sera were positive in the B. caballi IFAT while an additional five (4.8%) other specimens were diagnosed positive using the cELISA. The serological results showed that 13 (12.4%) horses had antibodies against both T. equi and B. caballi. The TaqMan real-time PCR detected DNA of piroplams in 33 (31.4%) samples while serological methods found antibodies in 38 (36.2%) horses.

Two hundred forty feral domestic cats trapped between 2004 and 2008 in the city centre and the suburb districts of Dubai, as well as in desert biotopes, were subjected to a complete parasitological dissection. The established parasite fauna consisted of Cystoisospora felis (12.9%), Cystoisospora rivolta (9.2%), Toxoplasma/Hammondia (0.8%), Heterophyes heterophyes (2.5%), Heterophyopsis continua (0.4%), Joyeuxiella spp. (65.8%), Diplopylidium noelleri (37.1%), Hydatigera taeniaeformis (16.7%), Taenia hydatigena (0.4%), Ancylostoma ceylanicum (8.8%), Ollulanus tricuspis (0.8%), Toxocara mystax (2.9%), Toxascaris leonina (0.8%), Pterygodermatites affinis (35.0%), Centrorhynchus aluconis (4.6%), Rhipicephalus sanguineus (4.2%), Xenopsylla astia (3.8%) and Synosternus pallidus (4.2%).