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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]

The hippocampus is essential for the formation and retrieval of memories and is a crucial neural structure sub-serving complex cognition. Adult hippocampal neurogenesis, the birth, migration and integration of new neurons, is thought to contribute to hippocampal circuit plasticity to augment function. We evaluated hippocampal volume in relation to brain volume in 375 mammal species and examined 71 mammal species for the presence of adult hippocampal neurogenesis using immunohistochemistry for doublecortin, an endogenous marker of immature neurons that can be used as a proxy marker for the presence of adult neurogenesis. We identified that the hippocampus in cetaceans (whales, dolphins and porpoises) is both absolutely and relatively small for their overall brain size, and found that the mammalian hippocampus scaled as an exponential function in relation to brain volume. In contrast, the amygdala was found to scale as a linear function of brain volume, but again, the relative size of the amygdala in cetaceans was small. The cetacean hippocampus lacks staining for doublecortin in the dentate gyrus and thus shows no clear signs of adult hippocampal neurogenesis. This lack of evidence of adult hippocampal neurogenesis, along with the small hippocampus, questions current assumptions regarding cognitive abilities associated with hippocampal function in the cetaceans. These anatomical features of the cetacean hippocampus may be related to the lack of postnatal sleep, causing a postnatal cessation of hippocampal neurogenesis. [ABSTRACT FROM AUTHOR]

Objective To detect Coxiella burnetii ( C. burnetii ) DNA in clinical specimens from camel, goats, cattle and sheep in the Kingdom of Saudi Arabia. Methods A total of 367 clinical samples including blood, milk, faeces and urine were collected from different livestock and subjected to PCR amplification using primers which amplify transposon-like region and transposase gene. Results Positive amplification from both regions was obtained from camel, goats and cattle but not from sheep. A percentage of 10.8% samples yielded positive PCR amplification from both blood and milk, where 15 of 139 blood and 16 of 148 milk samples were positive. Faeces and urine showed higher percentages of positive samples reaching 40.8% and 23.8% respectively. Conclusions The preferred route of shedding in camel appeared to be the faeces followed by urine, while that of goats appeared to be the faeces and that of the cattle appeared to be the milk. [ABSTRACT FROM AUTHOR]

The article discusses the problem concerning the increasing diversity of the Meriones libycus or also known as the Libyan jird. Topics covered include the prevalence of the subspecies of the Libyan jird in the Mongolian plateau and in Morocco as well as the examination of the genetic diversity of the jird which could be found in Tunisia and China. Also mentioned is the genetic differences between the samples of Meriones libycus from China and those from Saudi Arabia.

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 baseline haematological and biochemical data for adult individuals of the Libyan jird (Meriones libycus) collected during March/April 2012 from Janadriya area near Riyadh in central Saudi Arabia were determined during this study. Blood samples were collected from 46 animals (21 males and 25 females) using sterile capillary tubes from the orbital sinus and evaluated for haematological and biochemical parameters using HM5 haematology analyser and VS2 Vetscan biochemistry analyser. Haematological parameters investigated did not reveal any sex-associated clinically significant differences with the exception of the platelet counts and the plateletcrit which was found to be significantly higher in males compared to the females (p <0.05). There was no significant intersex differences in the biochemical parameters investigated with the exception of the Blood Urea Nitrogen (BUN) and the BUN/Ctreatinine ratio values being significantly higher in males compared to females (p <0.05). Haematological and serum biochemical parameters presented in this study are considered representative for healthy adult wild-caught M. libycus. Such data may provide valuable information for veterinarians and scientists using adult Libyan jirds in research on diseases or other experimental studies. [Copyright &y& Elsevier]

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]

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]

The article presents a study on the timing and patterns of molt of Kuhl's bat, Pipistrellus kuhlii from Unizah Province, Saudi Arabia. It discusses findings on the molting sequence among adult and young bats which usually occur following the breeding season, comparing the process between males and females. It explores the significance of having clear knowledge of the timing and patterns of molt when collecting hair samples for stable isotope analysis to determine places of origin of migrating bats.