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The Nubian ibex (Capra nubiana) occurs in information‐rich visual habitats including the edges of cliffs and escarpments. In addition to needing enhanced spatial resolution to find food and detect predators, enhanced visual sampling of the lower visual field would be advantageous for the control of locomotion in such precarious terrains. Using retinal wholemounts and stereology, we sought to measure how the ganglion cell density varies across the retina of the Nubian ibex to reveal which portions of its surroundings are sampled with high resolution. We estimated a total of ~1 million ganglion cells in the Nubian ibex retinal ganglion cell layer. Topographic variations of ganglion cell density reveal a temporal area, a horizontal streak, and a dorsotemporal extension, which are topographic retinal features also found in other artiodactyls. In contrast to savannah‐dwelling artiodactyls, the horizontal streak of the Nubian ibex appears loosely organized possibly reflecting a reduced predation risk in mountainous habitats. Estimates of spatial resolving power (~17 cycles/degree) for the temporal area would be reasonable to facilitate foraging in the frontal visual field. Embedded in the dorsotemporal extension, we also found an unusual dorsotemporal area not yet reported in any other mammal. Given its location and spatial resolving power (~6 cycles/degree), this specialization enhances visual sampling toward the lower visual field, which would be advantageous for visually guided locomotion. This study expands our understanding of the retinal organization in artiodactyls and offers insights on the importance of vision for the Nubian ibex ecology. [ABSTRACT FROM AUTHOR]

We set out to test whether the Ethiopian hedgehog, Paraechinus aethiopicus is a seasonal or aseasonal breeder and assess which environmental cues bring about both reproductive recrudescence and its subsequent regression. In this study, the body mass, morphometry of the reproductive tract the histology of the reproductive organs and the hormone concentrations of males and females were studied over 12 consecutive months in a wild population of the Ethiopian hedgehog from central Saudi Arabia. Using these data we investigated the potential proximate environmental cues that may trigger the onset of reproduction. Temperature is important for the initial activation of the males by bringing about an increase in testosterone concentration. In female hedgehogs the first rains trigger the onset of reproductive activation with ovulation. In turn increased temperature brings about the final activation of the males with increased testes size and seminiferous tubule diameter. Pregnancies were first recorded in early spring and summer coinciding with a rise in plasma progesterone concentration that peaked in spring. The Ethiopian hedgehog was found to exhibit marked seasonal reproduction. This study strengthens the findings that changes in rainfall and temperature in the Middle East are crucial cues for the onset of reproduction in small mammals. [ABSTRACT FROM AUTHOR]

The Arabian oryx, a moderately large mammal that inhabits a harsh desert environment, has been shown to exhibit seasonal variations in activity and inactivity patterns. Here we analyzed the continuous year-round activity patterns of twelve free-roaming Arabian oryx under natural conditions from two varying desert environments in Saudi Arabia using abdominally implanted activity meters. We simultaneously recorded weather parameters at both sites to determine whether environmental factors are responsible for temporal niche switching as well as the seasonal structuring and timing of this behavioural plasticity. Our results demonstrate that Arabian oryx undergo temporal niche switching of 24 h activity patterns at a seasonal level and exhibit distinct nocturnal/crepuscular activity during summer, diurnal activity during winter and intermittent patterns of behaviour during the transitional seasons of autumn and spring. In addition, the oryx exhibited inter- and intra-seasonal variations in the temporal budgeting of 24 h activity patterns. Strong relationships with both photoperiod and ambient temperatures were found and in some instances suggested that increasing ambient temperatures are a primary driving force behind seasonal shifts in activity patterns. These adaptive patterns may be dictated by the availability of food and water, which in turn are strongly influenced by seasonal climate variations. Overall, the adaptive responses of free-roaming Arabian oryx in such harsh and non-laboratorial conditions provide a framework for comparing wild populations as well as aiding conservation efforts. [ABSTRACT FROM AUTHOR]

The Arabian oryx, Oryx leucoryx , is a member of the superorder Cetartiodactyla and is native to the Arabian Desert. The desert environment can be considered extreme in which to sleep, as the ranges of temperatures experienced are beyond what most mammals encounter. The current study describes the nuclear organization and neuronal morphology of the systems that have been implicated in sleep control in other mammals for the Arabian oryx. The nuclei delineated include those revealed immunohistochemically as belonging to the cholinergic, catecholaminergic, serotonergic and orexinergic systems within the basal forebrain, hypothalamus, midbrain and pons. In addition, we examined the GABAergic neurons and their terminal networks surrounding or within these nuclei. The majority of the neuronal systems examined followed the typical mammalian organizational plan, but some differences were observed: (1) the neuronal morphology of the cholinergic laterodorsal tegmental (LDT) and pedunculopontine tegmental (PPT) nuclei, as well as the parvocellular subdivision of the orexinergic main cluster, exhibited Cetartiodactyl-specific features; (2) the dorsal division of the catecholaminergic anterior hypothalamic group (A15d), which has not been reported in any member of the Artiodactyla studied to date, was present in the brain of the Arabian oryx; and (3) the catecholaminergic tuberal cell group (A12) was notably more expansive than previously seen in any other mammal. The A12 nucleus has been associated functionally to osmoregulation in other mammals, and thus its expansion could potentially be a species specific feature of the Arabian oryx given their native desert environment and the need for extreme water conservation. [ABSTRACT FROM AUTHOR]

Most desert small mammals use mechanisms to avoid overheating or dehydration during summer (e.g. nocturnality or torpor), but some are apparently able to cope with higher body temperatures (T b ) than normally recorded for mammals (i.e. hyperthermia). In winter, some small desert mammals use torpor to conserve energy during cool periods. Still, surprisingly few studies have reported field body temperature patterns in small terrestrial mammals inhabiting deserts, so it is unclear how common hyperthermia and torpor are in desert mammals. We measured T b of a murid rodent, the Libyan jird ( Meriones libycus ), during both summer and winter in Saudi Arabia. Modal, minimum, and maximum T b s were higher in summer than in winter, with maximum T b s near 42 °C during summer, among the highest T b s ever recorded in wild mammals. Variation in T b was significantly higher during summer than winter, which was mostly related to passive warming throughout the day as ambient temperatures regularly exceeded 45 °C during summer. Conversely, during winter, T b s were highest during the nocturnal active period. While the summer T b s we recorded are among the highest ever for either murids or small desert mammals, we suspect this represents a lack of data on free-ranging small mammals more than unique adaptations by this species. [ABSTRACT FROM AUTHOR]

Media and World Health Organization (WHO) attention on Zika virus transmission at the 2016 Rio Olympic Games and the 2015 Ebola virus outbreak in West Africa diverted the attention of global public health authorities from other lethal infectious diseases with epidemic potential. Mass gatherings such as the annual Hajj pilgrimage hosted by Kingdom of Saudi Arabia attract huge crowds from all continents, creating high-risk conditions for the rapid global spread of infectious diseases. The highly lethal Middle Eastern respiratory syndrome coronavirus (MERS-CoV) remains in the WHO list of top emerging diseases likely to cause major epidemics. The 2015 MERS-CoV outbreak in South Korea, in which 184 MERS cases including 33 deaths occurred in 2 months, that was imported from the Middle East by a South Korean businessman was a wake-up call for the global community to refocus attention on MERS-CoV and other emerging and re-emerging infectious diseases with epidemic potential. The international donor community and Middle Eastern countries should make available resources for, and make a serious commitment to, taking forward a "One Health" global network for proactive surveillance, rapid detection, and prevention of MERS-CoV and other epidemic infectious diseases threats. [ABSTRACT FROM AUTHOR]

The Arabian oryx inhabits an environment where summer ambient temperatures can exceed 40 °C for extended periods of time. While the oryx uses a suite of adaptations that aid survival, the effects of this extreme environment on inactivity are unknown. To determine how the oryx manages inactivity seasonally, we measured the daily rhythm of body temperature and used fine-grain actigraphy, in 10 animals, to reveal when the animals were inactive in relation to ambient temperature and photoperiod. We demonstrate that during the cooler winter months, the oryx was inactive during the cooler parts of the 24-h day (predawn hours), showing a nighttime (nocturnal) inactivity pattern. In contrast, in the warmer summer months, the oryx displayed a bimodal inactivity pattern, with major inactivity bouts (those greater than 1 h) occurring equally during both the coolest part of the night (predawn hours) and the warmest part of the day (afternoon hours). Of note, the timing of the daily rhythm of body temperature did not vary seasonally, although the amplitude did change, leading to a seasonal alteration in the phase relationship between inactivity and the body temperature rhythm. Because during periods of inactivity the oryx were presumably asleep for much of the time, we speculate that the daytime shift in inactivity may allow the oryx to take advantage of the thermoregulatory physiology of sleep, which likely occurs when the animal is inactive for more than 1 h, to mitigate environmentally induced increases in body temperature. [ABSTRACT FROM AUTHOR]

The present study describes the organization of the nuclei of the cholinergic, catecholaminergic, serotonergic and orexinergic systems in the brains of two members of Euarchontoglires, Lepus capensis and Tupaia belangeri . The aim of the present study was to investigate the nuclear complement of these neural systems in comparison to previous studies on Euarchontoglires and generally with other mammalian species. Brains were coronally sectioned and immunohistochemically stained with antibodies against choline acetyltransferase, tyrosine hydroxylase, serotonin and orexin-A. The majority of nuclei revealed in the current study were similar between the species investigated and to mammals generally, but certain differences in the nuclear complement highlight potential phylogenetic interrelationships within the Euarchontoglires and across mammals. In the northern tree shrew the nucleus of the trapezoid body contained neurons immunoreactive to the choline acetyltransferase antibody with some of these neurons extending into the lamellae within the superior olivary nuclear complex (SON). The cholinergic nature of the neurons of this nucleus, and the extension of cholinergic neurons into the SON, has not been noted in any mammal studied to date. In addition, cholinergic neurons forming the medullary tegmental field were also present in the northern tree shrew. Regarding the catecholaminergic system, the cape hare presented with the rodent specific rostral dorsal midline medullary nucleus (C3), and the northern tree shrew lacked both the ventral and dorsal divisions of the anterior hypothalamic group (A15v and A15d). Both species were lacking the primate/megachiropteran specific compact portion of the locus coeruleus complex (A6c). The nuclei of the serotonergic and orexinergic systems of both species were similar to those seen across most Eutherian mammals. Our results lend support to the monophyly of the Glires, and more broadly suggest that the megachiropterans are more closely related to the primates than are any other members of Euarchontoglires studied to date. [ABSTRACT FROM AUTHOR]

A previous study investigating potential adult hippocampal neurogenesis in microchiropteran bats failed to reveal a strong presence of this neural trait. As microchiropterans have a high field metabolic rate and a small body mass, it is possible that capture/handling stress may lead to a decrease in the detectable presence of adult hippocampal neurogenesis. Here we looked for evidence of adult hippocampal neurogenesis using immunohistochemical techniques for the endogenous marker doublecortin (DCX) in 10 species of microchiropterans euthanized and perfusion fixed at specific time points following capture. Our results reveal that when euthanized and perfused within 15 min of capture, abundant putative adult hippocampal neurogenesis could be detected using DCX immunohistochemistry. Between 15 and 30 min post-capture, the detectable levels of DCX dropped dramatically and after 30 min post-capture, immunohistochemistry for DCX could not reveal any significant evidence of putative adult hippocampal neurogenesis. Thus, as with all other mammals studied to date apart from cetaceans, bats, including both microchiropterans and megachiropterans, appear to exhibit substantial levels of adult hippocampal neurogenesis. The present study underscores the concept that, as with laboratory experiments, studies conducted on wild-caught animals need to be cognizant of the fact that acute stress (capture/handling) may induce major changes in the appearance of specific neural traits. [ABSTRACT FROM AUTHOR]

The locomotory activity rhythms of Asian garden dormice, Eliomys melanurus from Saudi Arabia were investigated under controlled laboratory conditions. Animals were maintained under different lighting conditions for a period of two weeks each. Dormice exhibited predominantly nocturnal activity during the light/dark (LD) (mean % nocturnal activity: 95.5±0.9%) and dark/light (DL) (mean % nocturnal activity: 96.8±0.7%) light cycles. All animals expressed free-running rhythms of locomotor activity when subjected to constant darkness (mean τ: 24h06±0h09). Upon inversion of the LD cycle to DL, activity re-entrained to the new light cycle within 3 days. When the dark component of the day was lengthened to 8L:16D the active time increased significantly from 11h43±0h05 to 13h43±0h22. In contrast, when the dark component was shortened from 12L:12D to16L: 8D, the active time decreased significantly to 7h58±0h04. No difference was apparent in the locomotor activity at 20 and 30°C however, dormice became very inactive at 10°C. Overall, locomotor activity patterns of the Asian garden dormouse largely resemble those of other species of dormice. However, Asian garden dormice spent long periods of time inactive both during light and darkness, when exposed to an ambient temperature of 10°C, which may be related to the dramatic and sudden change in temperature. This period of inactivity may reflect a bout of torpor or the entering into a state of hibernation. [ABSTRACT FROM AUTHOR]

The circadian rhythm of locomotory activity in the Arabian spiny mouse, a desert living species, was investigated under controlled laboratory conditions. Ten individuals were subjected to successive light cycles. When subjected to a 12L:12D light cycle, locomotor activity was confined mainly to the dark phase (mean 94.2% ± 1.6%). During a period of constant darkness (DD), all animals expressed free running rhythms of locomotor activity (mean 23h49 ± 0h04). Following a second LD cycle, the light and dark phases were inversed (12D:12L). Activity shifted with the lights and was masked during the light phase, re-entrainment was rather slow (up to 10 days). The effect of varying ambient temperature (20–35 °C) on the locomotor activity under a 12L:12D cycle revealed that temperature had no distinct effect on the level of locomotor activity. When the dark component of the day was lengthened to 8L:16D, the mean percentage of activity during the dark increased to 96.0 ± 0.8%, while a significant decrease in night time activity was observed when the dark phase length was decreased to 16L:8D (78.29 ± 2.52%). The Arabian spiny mouse therefore behaves as other desert dwelling rodents and can be described as truly nocturnal. [ABSTRACT FROM AUTHOR]

Abstract: The animal–environment interaction is complex, and the ability to temporally organise locomotor activity provides adaptive and survival advantages. We investigated daily and circadian locomotor activity patterns of two jird species from Arabia occurring in dramatically different environments to determine the environmental effect on activity. The King jird occurs in mountainous regions of Azir where climatic conditions are cool and wet, while the Libyan jird inhabits low-lying hot sandy deserts where temperatures exceed 45 °C during summer. Six King jirds and nine Libyan jirds were subjected to a 12L:12D light cycle, a period of constant darkness (DD) and an inversed 12D:12L light cycle. Five of six King jirds and all Libyan jirds showed entrainment of their activity to the light cycles, most animals exhibited nocturnal activity. All entraining jirds showed circadian rhythmicity, with the periods of the rhythms very close to 24 h. Entraining jirds inversed their activity patterns when the light cycle was inversed. The two jird species displayed comparable amounts of nocturnal activity in all light cycles presented. The King jird showed larger intraspecific variability than the Libyan jird, which may reflect more plasticity in its circadian clock, allowing it to adapt quicker to environmental changes. [Copyright &y& Elsevier]

We investigated the circadian activity rhythm in the little-studied Wagner's gerbil (Gerbillus dasyurus) from the Raydah Protected Area, southwestern Saudi Arabia. In order to assess whether these animals possess an endogenous rhythm of locomotor activity that entrains to the light:dark cycle, they were subjected to three distinct light cycles: an LD cycle (12 h light/12 h dark), a DD cycle (constant darkness) and a DL light cycle (an inverse of the LD light cycle). All eight individuals studied exhibited entrainment of their activity to the light cycles. Under LD, the total percentage of activity during the dark phase was 93.7 ± 1.8%. Activity was distributed throughout the night (mean peak activity 22:46 ± 0:14). All eight animals expressed distinct endogenous free-running rhythms of locomotor activity (mean r = 23:55 ± 0:36). During constant darkness, animals still displayed more activity during the subjective night (75.6 ± 0.4%). Under the DL light cycle, the total percentage of activity was 92.7 ± 1.8% during the dark phase. In conclusion, the daily locomotor activity rhythm of Wagner's gerbil is strongly entrained by the light:dark cycle with the most activity concentrated during the night and consequently this desert-dwelling mammal may thus be considered truly nocturnal. [ABSTRACT FROM AUTHOR]

Abstract: The gastrointestinal parasites and prevalence of infestation in the Arabian red fox Vulpes vulpes arabica Thomas, were investigated at the King Khalid Wildlife Research Centre (KKWRC) in Thumamah, Riyadh Province, Saudi Arabia. Faecal samples were collected from 58 wild caught foxes while under anaesthesia and examined for gastrointestinal parasites stages. Male and female foxes were infected with three major groups of parasites; cestodes, nematodes, protozoa as well as an acanthocephalan. Faecal analyses revealed that 22 foxes (37.9%) were infected with two different Isospora spp. and three (5.2%) with an undescribed Eimeria sp., 12 (20.7%). Nine individuals (15.5%) harboured hookworms, (Trichosomoides sp.), two (3.5%) were infected with Trichuris sp. (probably Trichuris vulpes) and one individual (1.7%) with Taenia sp. (probably Taenia hydatigena). Carcasses of five male and three female foxes were necropsied. Four of the necropsied carcasses yielded Ancylostoma caninum, two each harboured Pterygodermatitis affinis, T. vulpes and Macracanthorhynchus catalinus, in six foxes Joyeuxiella echinorynchoides was found. Five and four foxes were infected with T. hydatigena and Diplopylidium nölleri, respectively. The possible role of the Arabian red fox as an intercalary host essential for the life cycle of Trichosomoides sp., common to the Libyan jird, Meriones libycus, in particular and the importance of this species as a vector for zoonotic infections and in the spread of other parasites to wild and domestic animals in general is discussed. [Copyright &y& Elsevier]

The animal-environment interaction is complex, and the ability to temporally organise locomotor activity provides adaptive and survival advantages. The daily and circadian rhythms of locomotor activity in the Desert hedgehog, Paraechinus aethiopicus, from the central deserts of Saudi Arabia were investigated under controlled laboratory conditions. Twelve individuals were subjected to different light cycles of approximately 3 weeks each: light/dark (12:12LD) cycle; a period of constant darkness (DD); an inverse of the LD (12:12 DL) cycle; a short day cycle (8:16LD); and a long day cycle (16:8LD). All the animals exhibited entrainment of their activity to the LD and DL lighting regimes. Locomotor activity of the Desert hedgehog occurred mostly during the dark phases of the LD, DL, long day and short day cycles. All entraining hedgehogs showed daily rhythmicity, with the periods of the rhythms very close to 24 h. Entrained hedgehogs, additionally, inversed their activity patterns when the light cycle was inversed. The Desert hedgehog, therefore, can be described as genuinely nocturnal with an endogenous rhythm of locomotor activity. • Desert hedgehogs from Saudi Arabia entrain their locomotor activity to light cycles • They can be described as genuinely nocturnal with an endogenous rhythm. • They have free-running rhythms around 24 h • Harsh environmental condition decrease behavioural plasticity • Global warming may decrease behavioural plasticity in hedgehogs [ABSTRACT FROM AUTHOR]

Simple Summary: This research represents the first analysis of the population genetics of the diplectanid monogenean Lamellodiscus echeneis, sampled from wild and cage-reared gilthead seabream Sparus aurata across fifteen locations in the Southern (Tunisia) and Northern (Italy and Spain) regions of the Mediterranean Sea. The comparison of the newly obtained dataset to previously published sequences of L. echeneis, and the phylogenetic trees based on the analysis of ITS rDNA, confirmed the presence of only one species in the Mediterranean Sea. The star-like haplotype network inferred by COI sequences suggested a recent population expansion of L. echeneis. This study provides insights into the genetic variation among L. echeneis populations and did not reveal a clear genetic structure throughout Tunisian, Italian, and Spanish localities, possibly due to significant gene flow between the populations facilitated by the dispersion potential of hosts. The diplectanid monogenean Lamellodiscus echeneis (Wagener, 1857) is a specific and common gill parasite of the gilthead seabream Sparus aurata Linnaeus, 1758, in the Mediterranean Sea. Few isolated molecular studies of this monogenean have been conducted, and its population structure and genetic diversity are poorly understood. This study represents the first analysis of the population genetics of L. echeneis, isolated from wild and cage-reared gilthead seabream from fifteen localities in both the Southern (Tunisia) and Northern (Italy and Spain) regions of the Mediterranean Sea, using nuclear ITS rDNA markers and a partial fragment of the mitochondrial gene cytochrome oxidase subunit I (COI). The phylogenetic trees based on the newly obtained dataset and the previously published sequences of L. echeneis corroborated the spread of only a single species throughout the Mediterranean Sea. The star-like haplotypes network, inferred by COI sequences, suggested a recent population expansion of L. echeneis. This is supported by the observed high haplotype diversity (Hd = 0.918) and low nucleotide diversity (Pi = 0.01595). Population structure-based AMOVA for two groups (the Adriatic Sea and the rest of the Mediterranean Sea) attributed 35.39% of the total variation to differences within populations, 16.63% to differences among populations within groups, and 47.99% to differences among groups. Fixation indices were significant, with a high FST value (0.64612), likely related to the divergence of the parasite populations from the Adriatic Sea and other Mediterranean regions. Phylogenetic analyses grouped all samples into the main clade corresponding to L. echeneis from several localities. This study provides insight into the genetic variation between L. echeneis populations, and did not show a clear genetic structure between populations of L. echeneis throughout Tunisian, Italian, and Spanish localities, which can be attributed to the considerable gene flow between the populations favoured by the potential for host dispersion within the Mediterranean Sea. Finally, haplotypes shared between wild and cage-reared hosts provided evidence for the potential for cross-infection between wild and farmed hosts in the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

Although the mammalian cerebral cortex is most often described as a hexalaminar structure, there are cortical areas (primary motor cortex) and species (elephants, cetaceans, and hippopotami), where a cytoarchitecturally indistinct, or absent, layer 4 is noted. Thalamocortical projections from the core, or first order, thalamic system terminate primarily in layers 4/inner 3. We explored the termination sites of core thalamocortical projections in cortical areas and in species where there is no cytoarchitecturally distinct layer 4 using the immunolocalization of vesicular glutamate transporter 2, a known marker of core thalamocortical axon terminals, in 31 mammal species spanning the eutherian radiation. Several variations from the canonical cortical column outline of layer 4 and core thalamocortical inputs were noted. In shrews/microchiropterans, layer 4 was present, but many core thalamocortical projections terminated in layer 1 in addition to layers 4 and inner 3. In primate primary visual cortex, the sublaminated layer 4 was associated with a specialized core thalamocortical projection pattern. In primate primary motor cortex, no cytoarchitecturally distinct layer 4 was evident and the core thalamocortical projections terminated throughout layer 3. In the African elephant, cetaceans, and river hippopotamus, no cytoarchitecturally distinct layer 4 was observed and core thalamocortical projections terminated primarily in inner layer 3 and less densely in outer layer 3. These findings are contextualized in terms of cortical processing, perception, and the evolutionary trajectory leading to an indistinct or absent cortical layer 4. [ABSTRACT FROM AUTHOR]

Background: Trombiculid mites are globally distributed, highly diverse arachnids that largely lack molecular resources such as whole mitogenomes for the elucidation of taxonomic relationships. Trombiculid larvae (chiggers) parasitise vertebrates and can transmit bacteria (Orientia spp.) responsible for scrub typhus, a zoonotic febrile illness. Orientia tsutsugamushi causes most cases of scrub typhus and is endemic to the Asia-Pacific Region, where it is transmitted by Leptotrombidium spp. chiggers. However, in Dubai, Candidatus Orientia chuto was isolated from a case of scrub typhus and is also known to circulate among rodents in Saudi Arabia and Kenya, although its vectors remain poorly defined. In addition to Orientia, chiggers are often infected with other potential pathogens or arthropod-specific endosymbionts, but their significance for trombiculid biology and public health is unclear. Results: Ten chigger species were collected from rodents in southwestern Saudi Arabia. Chiggers were pooled according to species and screened for Orientia DNA by PCR. Two species (Microtrombicula muhaylensis and Pentidionis agamae) produced positive results for the htrA gene, although Ca. Orientia chuto DNA was confirmed by Sanger sequencing only in P. agamae. Metagenomic sequencing of three pools of P. agamae provided evidence for two other bacterial associates: a spirochaete and a Wolbachia symbiont. Phylogenetic analysis of 16S rRNA and multi-locus sequence typing genes placed the spirochaete in a clade of micromammal-associated Borrelia spp. that are widely-distributed globally with no known vector. For the Wolbachia symbiont, a genome assembly was obtained that allowed phylogenetic localisation in a novel, divergent clade. Cytochrome c oxidase I (COI) barcodes for Saudi Arabian chiggers enabled comparisons with global chigger diversity, revealing several cases of discordance with classical taxonomy. Complete mitogenome assemblies were obtained for the three P. agamae pools and almost 50 SNPs were identified, despite a common geographic origin. Conclusions: P. agamae was identified as a potential vector of Ca. Orientia chuto on the Arabian Peninsula. The detection of an unusual Borrelia sp. and a divergent Wolbachia symbiont in P. agamae indicated links with chigger microbiomes in other parts of the world, while COI barcoding and mitogenomic analyses greatly extended our understanding of inter- and intraspecific relationships in trombiculid mites. [ABSTRACT FROM AUTHOR]

A collection of chigger mites from three species of rodents in the 'Asir Region of Saudi Arabia resulted in the finding of 19 species. Four new species are described: Schoutedenichia asirensissp. nov.,Schoutedenichia saudisp. nov.,Microtrombicula microscutasp. nov., and Microtrombicula muhaylensissp. nov. Fifteen species—Gahrliepia lawrenceiJadin and Vercammen-Grandjean, 1952, Schoengastiella wansoni Wolfs and Vercammen-Grandjean, Walchia parvula Schluger, Ascoschoengastia browni Taufflieb, Mouchet and Courtois, Helenicula lukshumiae Nadchatram and Traub, Schoutedenichia thracica Kolebinova, Schoutedenichia zarudnyi Kudryashova, Ericotrombidium caucasicum (Schluger), Ericotrombidium galliardi (Vercammen-Grandjean and Taufflieb), Ericotrombidium kazeruni (Kudryashova), Microtrombicula centropi (Vercammen-Grandjean), Microtrombicula hoogstraali (Radford), Microtrombicula hyracis (Vercammen-Grandjean), Microtrombicula traubi (Muljarskaja and Verdieva), and Pentidionis agamae (André)—are for the first time recorded in Saudi Arabia and on new host species. Six of them are for the first time recorded outside their type localities and five were only known previously from the African continent. [ABSTRACT FROM AUTHOR]

Bats are implicated as natural reservoirs for a wide range of zoonotic viruses including SARS and MERS coronaviruses, Ebola, Marburg, Nipah, Hendra, Rabies and other lyssaviruses. Accordingly, many One Health surveillance and viral discovery programs have focused on bats. In this report we present viral metagenomic data from bats collected in the Kingdom of Saudi Arabia [KSA]. Unbiased high throughput sequencing of fecal samples from 72 bat individuals comprising four species; lesser mouse-tailed bat (Rhinopoma hardwickii), Egyptian tomb bat (Taphozous perforatus), straw-colored fruit bat (Eidolon helvum), and Egyptian fruit bat (Rousettus aegyptiacus) revealed molecular evidence of a diverse set of viral families: Picornaviridae (hepatovirus, teschovirus, parechovirus), Reoviridae (rotavirus), Polyomaviridae (polyomavirus), Papillomaviridae (papillomavirus), Astroviridae (astrovirus), Caliciviridae (sapovirus), Coronaviridae (coronavirus), Adenoviridae (adenovirus), Paramyxoviridae (paramyxovirus), and unassigned mononegavirales (chuvirus). Additionally, we discovered a bastro-like virus (Middle East Hepe-Astrovirus), with a genomic organization similar to Hepeviridae. However, since it shared homology with Hepeviridae and Astroviridae at ORF1 and in ORF2, respectively, the newly discovered Hepe-Astrovirus may represent a phylogenetic bridge between Hepeviridae and Astroviridae. [ABSTRACT FROM AUTHOR]

A high percentage of camel handlers in Saudi Arabia are seropositive for Middle East respiratory syndrome coronavirus. We found that 12/100 camel handlers and their family members in Pakistan, a country with extensive camel MERS-CoV infection, were seropositive, indicating that MERS-CoV infection of these populations extends beyond the Arabian Peninsula. [ABSTRACT FROM AUTHOR]

Scrub typhus is a zoonosis caused by 3 species of Orientia bacteria, including Candidatus Orientia chuto. This species is known only from a human case in Dubai and infections in wildlife in Kenya. We report molecular detection of Candidatus O. chuto in 2 wild rodent species from Saudi Arabia. [ABSTRACT FROM AUTHOR]

In deserts where unpredictable rainfall arises and a large variation in temperature occurs, this poses severe energetic and water related constraints on reproduction in small mammals and makes the use of photoperiod as cue for reproduction unreliable. In the present study, the gonad morphometrics, gonadal histology and endocrine profiles of the Arabian spiny mouse ( Acomys dimidiatus ) were studied over 12 consecutive months in a field population from western Saudi Arabia in an attempt to assess the seasonality of reproduction and gain insights into the environmental cues that may trigger reproduction in this species. Although sperm was present throughout the year, most reproductive parameters exhibited a seasonal pattern with a minimum in winter in both sexes and pregnancies were observed from spring to autumn. Whereas testes volume, the number of corpora lutea and progesterone levels were correlated with temperature, all other reproductive parameters were correlated with rainfall. Thus, it appears that A. dimidiatus ceases to breed during winter and uses rainfall as an environmental cue to initiate reproduction in the study area. However, the species appears to have the ability to reproduce throughout the year, if favourable conditions arise. [ABSTRACT FROM AUTHOR]

The majority of human pathogens are zoonotic and rodents play an important role as reservoirs of many of these infectious agents. In the case of vector-borne pathogens, rodent reservoirs not only act as a source of infection for vectors but also serve as hosts for the vectors themselves, supporting their populations. Current data on rodent-ectoparasite relationships is limited in Saudi Arabia, however, this is needed to assess disease risk and the relative importance of different hosts for the maintenance of vector-borne pathogen cycles. In order to provide baseline data for the region that could be used to assess zoonotic disease risk, we collected and identified 771 ectoparasite specimens (ticks, fleas and mites) from 161 rodents at two wildlife research centres in Saudi Arabia and discuss our results in the context of possible zoonotic disease risk based on the hosts and vectors present. [ABSTRACT FROM AUTHOR]

There is little information pertaining to the reproductive biology of the Baluchistan gerbil ( Gerbillus nanus ) despite a broad distribution throughout the Middle East. In the current study, body mass, reproductive–tract morphometrics plus gonadal histology and endocrine profiles of males and females were studied over 12 consecutive months in a field population of Baluchistan gerbils from the western region of Saudi Arabia in an attempt to gain insights into a) the environmental zeitgeber ( s ) that correlate with reproduction as well as b) to assess if reproduction is seasonal or aseasonal in this species. With the exception of testosterone all male reproductive indicators varied seasonally and were lower during winter than the rest of the year and most increased with rainfall. In contrast, ovarian mass and volume as well as immature follicle counts showed no seasonal patterns and were independent of rainfall or temperature. First pregnancies were observed in late spring coinciding with the increased progesterone concentrations and peaked in summer. This was accompanied by seasonal peaks in the number of Graafian follicles and corpora lutea in females and these parameters were significantly correlated with temperature, but not rainfall In the Arabian Peninsula male, but not female Baluchistan gerbils show seasonal recrudescence and this appears to be correlated largely to rainfall. [ABSTRACT FROM AUTHOR]

Kuhl’s pipistrelle is found from Europe and North Africa all of the way to Asia, yet studies have thus far concentrated on the western limit of its distribution. Here we form a multi-marker picture of the diversity of Kuhl’s pipistrelle at a mid point in the Arabian peninsula in an attempt to redress the western sampling bias and to represent a region from which no genetic data has thus far been presented for this species. The three Arabian Cytochrome b haplotypes showed a clear divergence of 19 substitutions from those found in either Europe or North Africa. Molecular dating suggests the Arabian population split from the remaining Kuhl’s somewhere between 0.7 and 1.7 million years before present around the time of a series of aridification events across northern Africa. Well supported lineages within Arabia are typical of that which may be seen after an expansion from multiple Pleistocene refugia, but may also reflect the loss of intermediate haplotypes during historical population fluctuations. A long-term population contraction coincides with climatic changes towards those conditions more typical of contemporary Arabia. [ABSTRACT FROM AUTHOR]

Animal-attached devices have transformed our understanding of vertebrate ecology. To minimize any associated harm, researchers have long advocated that tag masses should not exceed 3% of carrier body mass. However, this ignores tag forces resulting from animal movement. Using data from collar-attached accelerometers on 10 diverse free-ranging terrestrial species from koalas to cheetahs, we detail a tag-based acceleration method to clarify acceptable tag mass limits. We quantify animal athleticism in terms of fractions of animal movement time devoted to different collar-recorded accelerations and convert those accelerations to forces (acceleration × tag mass) to allow derivation of any defined force limits for specified fractions of any animal's active time. Specifying that tags should exert forces that are less than 3% of the gravitational force exerted on the animal's body for 95% of the time led to corrected tag masses that should constitute between 1.6% and 2.98% of carrier mass, depending on athleticism. Strikingly, in four carnivore species encompassing two orders of magnitude in mass (ca 2–200 kg), forces exerted by '3%' tags were equivalent to 4–19% of carrier body mass during moving, with a maximum of 54% in a hunting cheetah. This fundamentally changes how acceptable tag mass limits should be determined by ethics bodies, irrespective of the force and time limits specified. [ABSTRACT FROM AUTHOR]

Background: The ixodid tick genera Rhipicephalus and Haemaphysalis contain several species of medical and/or veterinary importance, but their diversity in some regions of the world remains under-explored. For instance, very few modern studies have been performed on the taxonomy of these genera on the Arabian Peninsula. Methods: In this study, we trapped small mammals in the 'Asir Mountains of south-western Saudi Arabia and collected tick specimens for morphological examination and molecular barcoding, targeting three mitochondrial loci: cox1, 16S rRNA and 12S rRNA. Results: We obtained a total of 733 ticks (608 Haemaphysalis spp. and 125 Rhipicephalus spp.) from 75 small mammal hosts belonging to six species. All tick specimens were immature except for nine adults recovered from a hedgehog (Paraechinus aethiopicus). Morphologically, the Rhipicephalus ticks resembled R. camicasi, but the Haemaphysalis ticks showed differences in palp morphology compared with species previously described from Saudi Arabia. Phylogenetic analysis and automatic barcode gap discovery identified a novel clade of Rhipicephalus sp. representing most of the nymphs. This was most closely related to R. leporis, R. guilhoni and R. linnaei. The adult ticks and a small proportion of nymphs clustered with R. camicasi sequences from a previous study. Finally, the Haemaphysalis nymphs formed two distinct clades that were clearly separated from all reference sequences but closest to some African species. Conclusions: This apparent high level of tick diversity observed in a single study site of only ~ 170 km2, on a relatively small number of hosts, highlights the potential for the discovery of new tick species on the Arabian Peninsula. [ABSTRACT FROM AUTHOR]

Introgressive hybridization between domestic animals and their wild relatives is an indirect form of human‐induced evolution, altering gene pools and phenotypic traits of wild and domestic populations. Although this process is well documented in many taxa, its evolutionary consequences are poorly understood. In this study, we assess introgression patterns in admixed populations of Eurasian wolves and free‐ranging domestic dogs (FRDs), identifying chromosomal regions with significantly overrepresented hybrid ancestry and assessing whether genes located within these regions show signatures of selection. Although the dog admixture proportion in West Eurasian wolves (2.7%) was greater than the wolf admixture proportion in FRDs (0.75%), the number and average length of chromosomal blocks showing significant overrepresentation of hybrid ancestry were smaller in wolves than FRDs. In wolves, 6% of genes located within these blocks showed signatures of positive selection compared to 23% in FRDs. We found that introgression from wolves may provide a considerable adaptive advantage to FRDs, counterbalancing some of the negative effects of domestication, which can include reduced genetic diversity and excessive tameness. In wolves, introgression from FRDs is mostly driven by drift, with a small number of positively selected genes associated with brain function and behaviour. The predominance of drift may be the consequence of small effective size of wolf populations, which reduces efficiency of selection for weakly advantageous or against weakly disadvantageous introgressed variants. Small wolf population sizes result largely from human‐induced habitat loss and hunting, thus linking introgression rates to anthropogenic processes. Our results imply that maintenance of large population sizes should be an important element of wolf management strategies aimed at reducing introgression rates of dog‐derived variants. [ABSTRACT FROM AUTHOR]

In this study, we conducted molecular detection and characterization of piroplasms that infect the Ethiopian or desert hedgehogs (Paraechinus aethiopicus) in Saudi Arabia. Blood samples from 112 (68 males and 44 females) desert hedgehogs from Unaizah, Central Saudi Arabia were screened for Theileria/Babesia DNA using the polymerase chain reaction (PCR) employing specific primers amplifying the partial 18S small subunit rRNA gene. Theileria DNA was detected in 51 samples (45·5%), giving a prevalence of 45·5%. Theileria DNA was found in 33 (48·5%) males and 18 (40·9%) females, and there was no significant difference (P > 0·05) in the prevalence between males and females. Similarly, there was no significant difference (P > 0·05) in the prevalence between juveniles (40%) and adults (46·7%). There was a significant difference in the prevalence of Theileria in hedgehogs collected from May to September and the period from October to April (P = 0·003). Four haplotypes of Theileria sp. in hedgehogs were detected and designated as H1–H4. H1 was the predominant haplotype and found in 80·8% of the positive individuals. Partial sequences of the 18S rRNA of Theileria sp. from hedgehogs grouped with Theileria spp. that are benign. This study is the first report of the occurrence of Theileria spp. in Saudi Arabian desert hedgehogs. [ABSTRACT FROM AUTHOR]

To elucidate factors underlying the evolution of large brains in cetaceans, we examined 16 brains from 14 cetartiodactyl species, with immunohistochemical techniques, for evidence of non-shivering thermogenesis. We show that, in comparison to the 11 artiodactyl brains studied (from 11 species), the 5 cetacean brains (from 3 species), exhibit an expanded expression of uncoupling protein 1 (UCP1, UCPs being mitochondrial inner membrane proteins that dissipate the proton gradient to generate heat) in cortical neurons, immunolocalization of UCP4 within a substantial proportion of glia throughout the brain, and an increased density of noradrenergic axonal boutons (noradrenaline functioning to control concentrations of and activate UCPs). Thus, cetacean brains studied possess multiple characteristics indicative of intensified thermogenetic functionality that can be related to their current and historical obligatory aquatic niche. These findings necessitate reassessment of our concepts regarding the reasons for large brain evolution and associated functional capacities in cetaceans. [ABSTRACT FROM AUTHOR]

A novel species of coccidia, resembling a member of the genus Eimeria, was found in bats, Scotophilus leucogaster, collected in southern Saudi Arabia has been described on the basis of unsporulated oocysts and DNA sequencing of the Internal Transcribed Spacer 1 (ITS1) and partial 18S rDNA regions. Unsporulated oocysts of this form are ovoidal to spheroidal and had a 2-layered wall, 1.5–2.0 (1.9 ± 0.2); the outer layer was light blue with striations, and thicker than the inner, darker layer. No micropyle was present. Unsporulated oocysts (N = 150) measured 27.2 × 22.1 (25–30 × 20–25), length width ratio, 1.2 (1.1–1.4). There was no evidence of an oocyst residuum and/or polar granule. This parasite was detected in 2/7 (29%) S. leucogaster collected from southern Saudi Arabia. Oocysts incubated at 25 °C in 2.5% K2Cr2O7 did not sporulate after > 1 month. Unsporulated oocyst measurements were compared with other coccidian parasites of bats that discharge oocysts in their feces. Sequences of the ITS1 and the 18S rDNA regions obtained from the unsporulated oocysts grouped this coccidium from S. leucogaster with eimerian species from various rodent and squirrel species. It is critical that future investigators obtain fully sporulated oocysts of this coccidium for full description of the parasite recovered in our study so it can be correctly assigned to genus and given an accurate binomial. [ABSTRACT FROM AUTHOR]

This study aimed to assess the seasonal reproductive strategy occurring in the male Lesser Egyptian jerboa (Jaculus jaculus) and determine which environmental cues are responsible for initiating reproductive recrudescence. Body mass, morphometry of the reproductive tract, the histology of the testes and the circulating testosterone concentrations in wild male J. jaculus, from central Saudi Arabia, were studied over 12 consecutive months. Furthermore, sixteen additional males were collected and subsequently placed on either a short‐day (SD) or a long‐day (LD) light schedule under controlled laboratory conditions. Using these male reproductive parameters, we investigated the potential proximate environmental cues that may trigger the onset of reproduction. Unexpectedly, males were reproductively active during three out of the four seasons, namely autumn, winter and spring possibly due to the rainfall that fell at an unprecedented frequency and quantity during this time. However, we revealed the importance of other environmental triggers, namely photoperiod and ambient temperature, on the control of male reproduction in J. jaculus. Decreasing photoperiod (SD) and ambient temperature were observed to activate the reproductive system by increasing plasma testosterone concentration. The male Lesser Egyptian jerboa was found to exhibit a marked seasonal reproduction controlled by the environmental cues of ambient temperature and photoperiod. [ABSTRACT FROM AUTHOR]

The Middle East Respiratory Syndrome-Coronavirus (MERS-CoV) is an endemic virus in dromedaries. Annually, Saudi Arabia imports thousands of camels from the Horn of Africa, yet the epidemiology of MERS-CoV in these animals is largely unknown. Here, MERS-CoV prevalence was compared in imported African camels and their local counterparts. A total of 1399 paired sera and nasal swabs were collected from camels between 2016 and 2018. Imported animals from Sudan (n = 829) and Djibouti (n = 328) were sampled on incoming ships at Jeddah Islamic seaport before unloading, and local camels were sampled from Jeddah (n = 242). Samples were screened for neutralizing antibodies (nAbs) and MERS-CoV viral RNA. The overall seroprevalence was 92.7% and RNA detection rate was 17.2%. Imported camels had higher seroprevalence compared to resident herds (93.8% vs 87.6%, p <0.01) in contrast to RNA detection (13.3% vs 35.5%, p <0.0001). Seroprevalence significantly increased with age (p<0.0001) and viral RNA detection rate was ~2-folds higher in camels <2-year-old compared to older animals. RNA detection was higher in males verses females (24.3% vs 12.6%, p<0.0001) but seroprevalence was similar. Concurrent positivity for viral RNA and nAbs was found in >87% of the RNA positive animals, increased with age and was sex-dependent. Importantly, reduced viral RNA load was positively correlated with nAb titers. Our data confirm the widespread of MERS-CoV in imported and domestic camels in Saudi Arabia and highlight the need for continuous active surveillance and better prevention measures. Further studies are also warranted to understand camels correlates of protection for proper vaccine development. [ABSTRACT FROM AUTHOR]

Animal behavior is elicited, in part, in response to external conditions, but understanding how animals perceive the environment and make the decisions that bring about these behavioral responses is challenging. Animal heads often move during specific behaviors and, additionally, typically have sensory systems (notably vision, smell, and hearing) sampling in defined arcs (normally to the front of their heads). As such, head‐mounted electronic sensors consisting of accelerometers and magnetometers, which can be used to determine the movement and directionality of animal heads (where head "movement" is defined here as changes in heading [azimuth] and/or pitch [elevation angle]), can potentially provide information both on behaviors in general and also clarify which parts of the environment the animals might be prioritizing ("environmental framing"). We propose a new approach to visualize the data of such head‐mounted tags that combines the instantaneous outputs of head heading and pitch in a single intuitive spherical plot. This sphere has magnetic heading denoted by "longitude" position and head pitch by "latitude" on this "orientation sphere" (O‐sphere). We construct the O‐sphere for the head rotations of a number of vertebrates with contrasting body shape and ecology (oryx, sheep, tortoises, and turtles), illustrating various behaviors, including foraging, walking, and environmental scanning. We also propose correcting head orientations for body orientations to highlight specific heading‐independent head rotation, and propose the derivation of O‐sphere‐metrics, such as angular speed across the sphere. This should help identify the functions of various head behaviors. Visualizations of the O‐sphere provide an intuitive representation of animal behavior manifest via head orientation and rotation. This has ramifications for quantifying and understanding behaviors ranging from navigation through vigilance to feeding and, when used in tandem with body movement, should provide an important link between perception of the environment and response to it in free‐ranging animals. [ABSTRACT FROM AUTHOR]

Animal behavior is elicited, in part, in response to external conditions, but understanding how animals perceive the environment and make the decisions that bring about these behavioral responses is challenging.Animal heads often move during specific behaviors and, additionally, typically have sensory systems (notably vision, smell, and hearing) sampling in defined arcs (normally to the front of their heads). As such, head‐mounted electronic sensors consisting of accelerometers and magnetometers, which can be used to determine the movement and directionality of animal heads (where head "movement" is defined here as changes in heading [azimuth] and/or pitch [elevation angle]), can potentially provide information both on behaviors in general and also clarify which parts of the environment the animals might be prioritizing ("environmental framing").We propose a new approach to visualize the data of such head‐mounted tags that combines the instantaneous outputs of head heading and pitch in a single intuitive spherical plot. This sphere has magnetic heading denoted by "longitude" position and head pitch by "latitude" on this "orientation sphere" (O‐sphere).We construct the O‐sphere for the head rotations of a number of vertebrates with contrasting body shape and ecology (oryx, sheep, tortoises, and turtles), illustrating various behaviors, including foraging, walking, and environmental scanning. We also propose correcting head orientations for body orientations to highlight specific heading‐independent head rotation, and propose the derivation of O‐sphere‐metrics, such as angular speed across the sphere. This should help identify the functions of various head behaviors.Visualizations of the O‐sphere provide an intuitive representation of animal behavior manifest via head orientation and rotation. This has ramifications for quantifying and understanding behaviors ranging from navigation through vigilance to feeding and, when used in tandem with body movement, should provide an important link between perception of the environment and response to it in free‐ranging animals. [ABSTRACT FROM AUTHOR]

The present study was undertaken to confirm the genetic identity of Clostridium perfringens isolates from domestic livestock in Saudi Arabia and to characterize the genes encoding to alpha, beta, epsilon, and iota (α-, β-, ε-, and ι-) toxins. C. perfringens were confirmed in 104 out of 136 isolates on multiplex polymerase chain reaction using specific primers amplifying genes related to toxins produced by C. perfringens. Genes encoding α-toxins were detected in 104 samples. Of the isolates, 80.8% were diagnosed as type A, 15.4% as type D, 2.9% as type C, and 0.96% as type B. None of the isolates has genes encoding iota (ι-) toxin. All isolates investigated yielded enterotoxin (cpe) products and none yielded β2 (cpb2-toxin) or NetB products. PLC gene sequences encoding α-toxin showed >96.7% similarity. Isolates which had α-toxins as well as enterotoxin (cpe) are regarded as type F. Phylogenetic analysis using maximum likelihood analysis yielded two clades, and the majority of the isolates were in one group while only two isolates clustered on the second clade. Within the Kingdom of Saudi Arabia strains, 54 variable positions and 23 polymorphic amino acids were noticed. Isolates with ε- and β-toxins were variable and were found to be close to those published for C. perfringens. ETX gene sequences encoding ε-toxins were found to be related to CPE sequences. [ABSTRACT FROM AUTHOR]

Arid-dwelling mammals are exposed to extreme daily temperatures, which puts these mammals at risk of overheating and dehydration, particularly while active, these risks are increased as the body size is reduced. Consequently, these small mammals often show strict nocturnality, confining their locomotor activity to the dark period of the day. One such animal is the Lesser Egyptian Jerboa (Jaculus jaculus), which occurs in the hyper-arid central regions of the Arabian Peninsula. In this study, twelve male J. jaculus were subjected to different light regimes. All the animals exhibited entrainment of their activity to the dark phase of each respective light regime. However, unlike other small arid dwelling mammals, J. jaculus confined most of its activity during the last few hours of the night rather than the initial hours of the night, a pattern which is consistent even under constant DD conditions. The last few hours of the night correlate to the coolest experienced temperatures in summer in the wild and, therefore, the ideal time for a very small mammal to be active. Larger small mammals, which may be less at risk of overheating, can afford to be active during the warmer periods of the night, namely the initial hours. • Lesser Egyptian Jerboa (Jaculus jaculus) showed strict nocturnal locomotor activity under laboratory conditions. • In contrast to other small mammals, J. jaculus confined most of its activity during the last few hours of the night. • Evolutionary pressures driving nocturnal activity in small mammals that inhabit hyper-arid regions are tremendous. • Body mass likely affects small mammal nocturnal behaviour and chronobiology. [ABSTRACT FROM AUTHOR]

The liver fluke Fasciola hepatica is the main cause of fasciolosis in North Africa leading to significant economic losses and public health problems. In this study, the ribosomal internal transcribed spacer (ITS), cytochrome c oxidase I (COI), the mitochondrial region spanning the COI-trnT-rrnL, and the NADH dehydrogenase subunit I (NADI) markers were used to characterize Fasciola flukes from Algeria. Fasciola appeared widespread from the east to the west of Algeria. Among 1701 sampled cattle from 8 Algerian provinces, 5% were infected. Using morphological and morphometric analysis, one morphotype of Fasciola was observed. Nuclear ITS marker indicated that all collected flukes belong to F. hepatica. Multiple alignments of ITS dataset revealed two haplotypes, one described here for the first time. Analysis of molecular variance (AMOVA) of mitochondrial markers revealed weak population structure in Algeria. Mismatch distributions, neutrality tests, and median-joining network analysis all were compatible with a recent expansion of Algerian F. hepatica population. Fasciolosis appeared common in Algerian cattle, it seems that the absence of control strategy coupled to the favorable Mediterranean climate may lead to a reconstruction and dispersion of its populations. This study provides important results concerning the genetic characterization and variability of F. hepatica in Algeria as well as the significant role of cattle importation in shaping its dispersal route worldwide. [ABSTRACT FROM AUTHOR]

The reproductive pattern of the Libyan jird (Meriones libycus Lichtenstein, 1823) from central Saudi Arabia was investigated in the absence of rainfall. In this study, body mass, morphometry of the reproductive tract, the histology of the reproductive organs, and the hormone concentrations of males and females were studied over 12 consecutive months in a wild population of the Libyan jird from central Saudi Arabia. Previous studies have found the breeding season of the Libyan jird from the Sahara desert of Algeria to occur during the wet months of spring. In the absence of rainfall, temperature and photoperiod were found to be important activators of reproductive activity. The cooler temperatures and shorter days of winter triggered the onset of ovulation in females and increased testes size and seminiferous tubule diameter in males. Only two pregnancies were found during the sampling period, which occurred during the cooler winter and early spring and coincided with a rise in plasma progesterone concentration in females. The Libyan jird was found to shift its breeding to the cooler months of winter in the absence of rainfall. This study strengthens the findings that changes in rainfall and temperature in dry deserts are critical cues for the onset of reproduction in small mammals. [ABSTRACT FROM AUTHOR]

Abstract Since 2012, MERS-CoV has caused up to 2220 cases and 790 deaths in 27 countries with Saudi Arabia being the most affected country with ~83.1% of the cases and ~38.8% local death rate. Current serological assays such as microneutralization (MN), plaque reduction neutralization, immunofluorescence, protein microarray or pseudoparticle neutralization assays rely on handling of live MERS-CoV in high containment laboratories or need for expensive and special equipment and reagents and highly trained personnel which represent a technical hurdle for most laboratories in resource-limited MERS-CoV endemic countries. Here, we developed, compared and evaluated three different indirect ELISAs based on MERS-CoV nucleocapsid protein (N), spike (S) ectodomain (amino acids 1–1297) and S1 subunit (amino acids 1–725) and compared them with MN assay. The developed ELISAs were evaluated using large number of confirmed seropositive (79 samples) and seronegative (274 samples) MERS-CoV human serum samples. Both rS1- and rS-ELISAs maintained high sensitivity and specificity (≥90%) across a wider range of OD values compared to rN-ELISA. Moreover, rS1- and rS-based ELISAs showed better agreement and correlation with MN assay in contrast to rN-ELISA. Collectively, our data demonstrate that rS1-ELISA and rS-ELISA are more reliable than rN-ELISA and represent a suitable choice for seroepidemiological testing and surveillance in MERS-CoV endemic regions. [ABSTRACT FROM AUTHOR]

Abstract Bartonellae bacteria are associated with several re-emerging human diseases. These vector-borne pathogens have a global distribution, yet data on Bartonella prevalence and diversity in the Arabian Peninsula are limited. In this study we assessed the Bartonella infection status of the Baluchistan gerbil (Gerbillus nanus), a species associated with pastoral communities throughout the Middle East region, using a multi-gene PCR screening approach. The results demonstrated that 94 (68.1%) of the 138 gerbils trapped on a monthly basis, over a period of one year, were PCR-positive. Sequencing of the gltA gene region confirmed the presence of four discrete Bartonella lineages (I–IV) and high levels of co-infection (33.0%). Each of the four lineages, varied in overall abundance (7.5%–47.9%) and had discernible seasonal peaks. Bartonella status was significantly correlated with ectoparasite presence, but not with sex, nor with season. Statistical analyses further revealed that co-infected individuals had a significantly higher relative body condition. Multi-locus sequence analysis (MLSA) performed with a concatenated dataset of three genetic loci (gltA , nuoG , and rpoB), 1452 nucleotides (nt) in length confirmed that lineage IV, which occurred in 24 PCR-positive animals (25.5%), is most closely related to zoonotic B. elizabethae. The remaining three lineages (I-III) formed a monophyletic clade which, on the basis of gltA was shown to contain bartonellae from diverse Gerbillinae species from the Middle East, suggestive of a gerbil-associated species complex in this region. Lineage I was identical to a Candidatus B. sanaae strain identified previously in Bushy-tailed jirds (Sekeetamys calurus) from Egypt, wherease MLSA indicate that lineages II and III are novel. The high levels of infection and co-infection, together with the presence of multiple Bartonella lineages indicate that Gerbillus nanus is likely a natural reservoir of Bartonella in the Arabian Peninsula. Highlights • 68% of Gerbillus nanus from Saudi Arabia infected with Bartonella. • Four Bartonella lineages recovered; one closely related to zoonotic B. elizabethae. • Lineages vary seasonally and in overall abundance, ranging from 7% to 48%. • High level of co-infected individuals (33%) [ABSTRACT FROM AUTHOR]

Heterakis gallinarum is one of the most recurrently diagnosed nematodes within the gastrointestinal tract of galliform birds. In the present study, we investigated the genetic diversity of 96 H. gallinarum collected from free-range chickens from different localities in Tunisia. We assessed phylogeny and genetic variability using the internal transcribed spacers (ITS) of the nuclear ribosomal DNA and the mitochondrial cytochrome c oxidase subunit I gene. Haplotype and nucleotide diversities indicate that H. gallinarum is a species with extremely low genetic diversity. Based on the networks and phylogenetic trees, there was strong support for the absence of significant geographical structuring among the H. gallinarum populations in different localities in Tunisia. Mismatch distributions and neutrality tests of both genetic markers suggest that at least one expansion event occurred in the population demographic history of H. gallinarum. Our data showed a lack of population structure using the pairwise fixation index (FST) and an extensive gene flow. It indicated that the most likely major contributor to the low genetic diversity and gene flow is the movement of the parasitized birds; in other words, the frequency of the poultry trade considerably affects patterns of worm gene flow. [ABSTRACT FROM AUTHOR]

The present study used two mitochondrial markers (16S rRNA and COI) to assess the genetic diversity of a newly founded Lessepsian migrant mussel, Brachidontes pharaonis, in Tunisian waters. The species appears to be restricted to only one population in Rades Harbour, in the northern part of the country. Phylogenetic analyses revealed the monophyly of B. pharaonis in Tunisia. Both molecular markers revealed high genetic variability of the B. pharaonis population. Haplotype networks and demographic analyses confirmed the recent expansion events within this population. Multiple human-mediated introduction events involving several founder populations and intensive population growth rates are probably the main causes of the high polymorphism observed within this invasive mollusc. [ABSTRACT FROM AUTHOR]

Heterothermy, the ability to allow body temperature (Tb) to fluctuate, has been proposed as an adaptive mechanism that enables large ungulates to cope with the high environmental temperatures and lack of free water experienced in arid environments. By storing heat during the daytime and dissipating it during the night, arid-adapted ungulates may reduce evaporative water loss and conserve water. Adaptive heterothermy in large ungulates should be particularly pronounced in hot environments with severely limited access to free water. In the current study we investigated the effects of environmental temperature (ambient, Ta and soil, Ts) and water stress on the Tb of wild, free-ranging Arabian oryx (Oryx leucoryx) in two different sites in Saudi Arabia, Mahazat as-Sayd (MS) and Uruq Bani Ma’arid (UBM). Using implanted data loggers wet took continuous Tb readings every 10 minutes for an entire calendar year and determined the Tb amplitude as well as the heterothermy index (HI). Both differed significantly between sites but contrary to our expectations they were greater in MS despite its lower environmental temperatures and higher rainfall. This may be partially attributable to a higher activity in an unfamiliar environment for translocated animals in UBM. As expected Tb amplitude and HI were greatest during summer. Only minor sex differences were apparent that may be attributable to sex-specific investment into reproduction (e.g. male-male competition) during rut. Our results suggest that the degree of heterothermy is not only driven by extrinsic factors (e.g. environmental temperatures and water availability), but may also be affected by intrinsic factors (e.g. sex and/or behaviour). [ABSTRACT FROM AUTHOR]

Documenting variation in thermoregulatory patterns across phylogenetically and geographically diverse taxa is key to understanding the evolution of endothermy and heterothermy in birds and mammals. We recorded body temperature (Tb) in free-ranging desert hedgehogs (Paraechinus aethiopicus) across three seasons in the deserts of Saudi Arabia. Modal Tb’s (35°–36.5°C) were slightly below normal for mammals but still warmer than those of other hedgehogs. The single maximum Tb recorded was 39.2°C, which is cooler than maximum Tb’s recorded in most desert mammals. Desert hedgehogs commonly used torpor during winter and spring but never during summer. Torpor bouts occurred frequently but irregularly, and most lasted less than 24 h. Unlike daily heterotherms, desert hedgehogs did occasionally remain torpid for more than 24 h, including one bout of 101 h. Body temperatures during torpor were often within 2°–3°C of ambient temperature; however, we never recorded repeated bouts of long, predictable torpor punctuated by brief arousal periods similar to those common among seasonal hibernators. Thus, desert hedgehogs can be included on the ever-growing list of species that display torpor patterns intermediate to traditionally defined hibernators and daily heterotherms. Extant hedgehogs are a recent radiation within an ancient family, and the intermediate thermoregulatory pattern displayed by desert hedgehogs is unlike the deeper and more regular torpor seen in other hedgehogs, suggesting that this may be a derived—as opposed to ancestral—trait in this subfamily. We suggest that this family (Erinaceidae) and order (Eulipotyphla) may be important for understanding the evolution of thermoregulatory patterns among Laurasiatheria and mammals in general. [ABSTRACT FROM AUTHOR]

Objective To study the effect of heterothermia on anaesthetic drug requirements in semi-free ranging Arabian oryx and to assess the temperature quotient (Q10) of oxygen consumption. Study design Prospective observational study and controlled metabolic experiment. Animals Sixty-eight anaesthetic events in 59 Arabian oryx fromMahazat As-Sayd protected area, Saudi Arabia. Methods Anaesthesia was induced by remote injection of 25 mg ketamine, 10 mg midazolam and 0.5 mg medetomidine with a variable amount of etorphine based on a target dosage of 20 µg kg-1 and subjective assessment of body mass. Animals not recumbent within 15minutes or insufficiently anaesthetized were physically restrained and administered supplementary etorphine intravenously depending on the anaesthetic depth. Body temperature (Tb) was measured rectally immediately upon handling of each animal. Fromsix anaesthetized oryx, expiratory gasses for oxygen analysis and metabolic rate calculation were collected at twoTbs; before and after submersion in icewater for approximately 30 minutes. Results: Forty-two animals (62%) became recumbent with the initial dose, with a mean induction time (± standard deviation) of 9 ± 2 minutes. The remaining animals could be handled but needed 0.3 ± 0.1 mg etorphine intravenously to reach the desired level of anaesthesia. There was a significant positive correlation between Tb and effective etorphine dosage (R² = 0.48, p < 0.0001). Average Tb of the six animals in which metabolic rate was measured decreased from 40.0 ± 0.5°C immediately after induction to 35.5 ± 0.5°C after cooling. This reduction was associated with a reduction in oxygen uptake from 3.11 ± 0.33 to 2.22 ± 0.29 mL O2 minute-1 kg-1, reflected in Q10 of 2.17 ± 0.14. Conclusions and clinical relevance: Tb significantly affects anaesthetic requirements in Arabian oryx and should be considered when selecting dosages for anaesthetic induction for species showing diurnal heterothermy. [ABSTRACT FROM AUTHOR]

Domesticated species are often composed of distinct populations differing in the character and strength of artificial and natural selection pressures, providing a valuable model to study adaptation. In contrast to pure-breed dogs that constitute artificially maintained inbred lines, free-ranging dogs are typically free-breeding, i.e., unrestrained in mate choice. Many traits in free-breeding dogs (FBDs) may be under similar natural and sexual selection conditions to wild canids, while relaxation of sexual selection is expected in pure-breed dogs. We used a Bayesian approach with strict false-positive control criteria to identify FST-outlier SNPs between FBDs and either European or East Asian breeds, based on 167,989 autosomal SNPs. By identifying outlier SNPs located within coding genes, we found four candidate genes under diversifying selection shared by these two comparisons. Three of them are associated with the Hedgehog (HH) signaling pathway regulating vertebrate morphogenesis. A comparison between FBDs and East Asian breeds also revealed diversifying selection on the BBS6 gene, which was earlier shown to cause snout shortening and dental crowding via disrupted HH signaling. Our results suggest that relaxation of natural and sexual selection in pure-breed dogs as opposed to FBDs could have led to mild changes in regulation of the HH signaling pathway. HH inhibits adhesion and the migration of neural crest cells from the neural tube, and minor deficits of these cells during embryonic development have been proposed as the underlying cause of “domestication syndrome.” This suggests that the process of breed formation involved the same genetic and developmental pathways as the process of domestication. [ABSTRACT FROM AUTHOR]

Summary The appearance of novel pathogens of humans with epidemic potential and high mortality rates have threatened global health security for centuries. Over the past few decades new zoonotic infectious diseases of humans caused by pathogens arising from animal reservoirs have included West Nile virus, Yellow fever virus, Ebola virus, Nipah virus, Lassa Fever virus, Hanta virus, Dengue fever virus, Rift Valley fever virus, Crimean-Congo haemorrhagic fever virus, severe acute respiratory syndrome coronavirus, highly pathogenic avian influenza viruses, Middle East Respiratory Syndrome Coronavirus, and Zika virus. The recent Ebola Virus Disease epidemic in West Africa and the ongoing Zika Virus outbreak in South America highlight the urgent need for local, regional and international public health systems to be be more coordinated and better prepared. The One Health concept focuses on the relationship and interconnectedness between Humans, Animals and the Environment, and recognizes that the health and wellbeing of humans is intimately connected to the health of animals and their environment (and vice versa). Critical to the establishment of a One Health platform is the creation of a multidisciplinary team with a range of expertise including public health officers, physicians, veterinarians, animal husbandry specialists, agriculturalists, ecologists, vector biologists, viral phylogeneticists, and researchers to co-operate, collaborate to learn more about zoonotic spread between animals, humans and the environment and to monitor, respond to and prevent major outbreaks. We discuss the unique opportunities for Middle Eastern and African stakeholders to take leadership in building equitable and effective partnerships with all stakeholders involved in human and health systems to take forward a ‘One Health’ approach to control such zoonotic pathogens with epidemic potential. [ABSTRACT FROM AUTHOR]

The organization of the cholinergic, catecholaminergic, and serotonergic neurons in the brains of five species of insectivores and the orexinergic (hypocretinergic) system in four insectivore species is presented. We aimed to investigate the nuclear complement of these neural systems in comparison to those of other mammalian species. Brains of insectivores were coronally sectioned and immunohistochemically stained with antibodies against choline acetyltransferase, tyrosine hydroxylase, serotonin and orexin-A. The majority of nuclei were similar among the species investigated and to mammals in general, but certain differences in the nuclear complement highlighted potential phylogenetic interrelationships. In the cholinergic system, the three shrew species lacked parabigeminal and Edinger–Westphal nuclei. In addition, the appearance of the laterodorsal tegmental nucleus in all insectivores revealed a mediodorsal arch. All three of these features are the same as those present in microchiropterans. The catecholaminergic system of the three shrew species lacked the A4 and A15d nuclei, as well as having an incipient A9v nucleus, again features found in microchiropteran brains. The serotonergic and orexinergic systems of the insectivores are similar to those seen across most eutherian mammals. The analysis of similarities and differences across mammalian species indicates a potential phylogenetic relationship between the Soricidae (shrews) and the microchiropterans. [ABSTRACT FROM AUTHOR]