Serologic surveillance for selected viral agents in captive and free-ranging populations of Arabian oryx (Oryx leucoryx) from Saudi Arabia and the United Arab Emirates

A total of 294 sera collected between 1999 and 2001 from eight captive and one free-ranging herds of Arabian oryx (Oryx leucoryx) distributed in Saudi Arabia (SA) and the United Arab Emirates (UAE) were assayed for antibodies against 13 selected viral agents. Arabian oryx have been exposed to bluetongue virus (BTV), epizootic hemorrhagic disease virus (EHDV), rinderpest virus (RPV), bovine respiratory syncytial virus (BRSV), bovine adenovirus 3 (BAV-3), cervid herpesvirus-1, foot-and-mouth disease virus, equine herpesvirus 9, and bovine viral diarrhea virus. The high seroprevalence to BTV and EHDV in the UAE and SA indicates that Arabian oryx are likely to be susceptible to infection by these viruses and therefore could act as a source of virus to vectors during the infective stage of infection. Moreover, antibodies were detected against RPV and BRSV in sera from SA and against BAV-3 in sera from the UAE. No antibodies were found against bovine herpesvirus-1, caprine herpesvirus-1, enzootic bovine leucosis virus, and peste des petits ruminants virus. On the basis of these results, caution should be applied when considering translocation of Arabian oryx, and only those proven to be free of infectious agents that might present a risk to other species should be moved.     

Melengestrol acetate implant contraception in addax (Addax Nasomaculatus) and Arabian oryx (Oryx Leucoryx)

Melengestrol acetate (MGA) implants were used for contraception in three addax and three Arabian oryx females housed at the Saint Louis Zoo. Serum estradiol and progesterone or fecal estrogen and progestin analysis and ultrasonography of reproductive tracts were used for monitoring changes before, during, and after MGA treatment. Follicular development and irregular uterine fluid accumulation were detected in all females during MGA treatment. Although housed with an intact male for all or most of the contraceptive period, no pregnancies occurred. One female addax may have ovulated, based on sustained elevated progesterone levels, and another showed continued follicle development, as seen by fluctuating estradiol concentrations. Reversibility was documented in two of the three addax that resumed reproductive cycles post‐MGA‐implant removal, whereas the third, a peripubertal female, did not cycle before, during, or after treatment. Addax females were lost to further follow‐up after transfer to another institution, so the possibility of subsequent pregnancies is not known. All three Arabian oryx ovulated during the initial MGA treatment, but two of the three females had implants past the typical 2‐year efficacy period. They had regular ovulatory cycles after implant removal, with mean cycle length of 27.5±1.5 days and mean luteal phase duration of 15.2±0.7 days. Reversibility was further shown in all three oryx by pregnancies after placement with a male approximately 2 years after MGA implant removal. Two produced healthy calves, but the third died owing to an unrelated terminal illness in the mother. Zoo Biol 26:299–310, 2007. © 2007 Wiley‐Liss, Inc.     

Application of mitochondrial genes sequences for measuring the genetic diversity of Arabian oryx

Arabian oryx (Oryx leucoryx) had faced extinction in the wild more than three decades ago and was saved by the prudent efforts of captive breeding programs. A clear understanding of the molecular diversity of contemporary Arabian oryx population is important for the long term success of captive breeding and reintroduction of this potentially endangered species. We have sequenced the segments of mitochondrial DNA including12S rRNA, 16S rRNA, cytochrome b (Cyt-b) and control region (CR) genes of 24 captive-bred and reintroduced animals. Although the sequences of 12S rRNA, 16S rRNA and Cyt-b were found to be identical for all the samples, typical sequence variations in the CR gene were observed in the form of 7 haplotypes. One of these haplotypes has been reported earlier while the remaining 6 haplotypes are novel and represent different lineages from the founders. The haplotype and nucleotide diversities were found to be 0.789 and 0.009 respectively. The genetic distances among the 7 mtDNA haplotypes varied from 0.001 to 0.017. These findings are of potential relevance to the management of captive breeding programs for the conservation of Arabian oryx.     

Comparisons among selected neonatal biomedical parameters of four species of semi-free ranging Hippotragini: Addax (Addax nasomaculatus), scimitar-horned oryx (Oryx dammah), Arabian oryx (Oryx leucoryx), and sable antelope (Hippotragus niger)

Basic biomedical data from 164 neonates of four species of the tribe Hippotragini, addax (Addax nasomaculatus), scimitar-horned oryx (Oryx dammah), Arabian oryx (Oryx leucoryx), and sable antelope (Hippotragus niger), were compared at one zoological institution over a 9-year period. Measured biomedical parameters included body weight, temperature, pulse and respiratory rates, packed cell volume (PCV), total plasma protein, glucose, IgG assessment via zinc sulfate turbidity, and white blood cell count with differential. All species were maintained in a semi-free ranging setting with the same diet, available shelter, and opportunity for social interaction. Based on clinical and field observations, all neonates used in the study were believed to be at least 24 hr old, to have bonded with the dam, and to have no obvious physical abnormalities. Median body weights were similar only in the addax and Arabian oryx with sable antelope having the largest median body weight. No significant differences in rectal temperatures or pulse rates were found among species. Median respiratory rates were similar between certain groups. Arabian oryx and scimitar-horned oryx shared the highest packed cell volumes while the sable antelope had the lowest. Sable antelope had the highest median total plasma protein with no significant differences among the other species. Sable were also significantly lower in median blood glucose than the three other Hippotraginae. Zinc sulfate turbidities in all species were similar. Addax had higher median total white blood cell counts than sable. No significant differences in the median numbers of segmented neutrophils, band neutrophils, and eosinophils were detected among species. Basophils were only found in the scimitar-horned oryx in one animal. Addax had higher median lymphocyte counts than sable and Arabian oryx as well as higher median monocyte counts than sable. All four species exhibited higher median counts of neutrophils compared with lymphocytes. The biomedical differences observed highlight the importance of having an accurate database of clinical normal values against which to evaluate neonatal health. Zoo Biol 20:47-54, 2001. Copyright 2001 Wiley-Liss, Inc.     

Characterization of male reproductive anatomy of the endangered Arabian oryx (Oryx leucoryx)

Reproductive tracts of four male Arabian oryx (Oryx leucoryx) from Shaumari Nature Reserve in Jordan were examined to characterize their reproductive anatomy. Animals were allocated into two groups based on their age: Group 1 (n = 2, males were 12 and 14 mo old) and Group 2 (n = 2, males were 7 and 9 yrs old). Observations regarding the morphology, position and orientation of different reproductive organs were made. The external and internal genital organs of male oryx were similar to other domestic ruminant species with minor differences.     

Genetic variability in the Arabian oryx (Oryx leucoryx)

An electrophoretic survey of blood markers of the Arabian oryx (Oryx leucoryx) was undertaken in order to ascertain the genetic variability in a sample of 85 individuals, mainly from Saudi Arabian (Taíf) and Jordanian herds. Three out of 18 loci were found to be polymorphic (P = 16.7%) and the mean heterozygosity (H = 0.052) appears to be relatively high with respect to the severe demographic bottlenecks expressed by the species since the 1960s. No genetic differentiation was found between Arabian and Jordanian samples considered. Consequences of these findings for the management of the Taíf herd and for such procedures as pedigree determination are discussed, and an example of this latter application is given for a case of doubtful parentage.     

Tear production in three captive wild herbivores in Israel

The Schirmer tear test (STT) I was performed to evaluate tear production in 12 captive Nubian ibex (Capra ibex nubiana), 10 captive Burchell's zebras (Equus burchelli) and five Arabian oryx (Oryx leucoryx) at the Tel-Aviv Ramat-Gan Zoological Center (Israel). Mean (+/- standard deviation) STT values were 13.2 +/- 5.1 mm/min in the ibex, 23.4 +/- 3.4 mm/min in the zebra and 12.7 +/- 4.8 mm/min in the oryx. There were no significant effects of gender, age, weight, or side of the eye. There were no significant differences in STT values between ibex and oryx, but tear production in both species was significantly lower than in zebras. Knowledge of normal tear production values is important for the differential diagnosis of conjunctivitis and keratitis in these species.     

The G- and C-banding karyotype of the Arabian oryx (Oryx leucoryx)

The chromosomes of the Arabian oryx (Oryx leucoryx) were investigated using GTG and CBG banding technique. Their banding patterns were compared to those of goat and cattle.     

Did the Arabian Oryx live in Egypt during pharaonic times?

Thanks to a colour reproduction faithfully completed by French explorer Frédéric Cailliaud in the early XIX^th century, we are able to view a missing Theban painting dating from the reign of Amenophis II (under the New Empire). It depicts a hunting scene in the desert and an oryx whose morphology and, above all, whose coat colouration obviously match those of the Arabian Oryx. Consequently, we put forward the hypothesis of the possible presence of the Arabian Oryx in the Eastern Desert in Egypt during pharaonic times.     

Development of a dual recombinant vaccine to protect small ruminants against peste-des-petits-ruminants virus and capripoxvirus infections

A recombinant capripoxvirus vaccine containing a cDNA of the peste-des-petits-ruminants virus (PPRV) fusion protein gene was constructed. A quick and efficient method was used to select a highly purified recombinant virus clone. A trial showed that a dose of this recombinant as low as 0.1 PFU protected goats against challenge with a virulent PPRV strain.     

Robertsonian chromosome polymorphism in the Arabian oryx (Oryx leucoryx)

A Robertsonian translocation was found in a herd of Arabian oryx (Oryx leucoryx). The translocated chromosome, when analyzed by G-banding, seemed to involve the fusion of chromosomes 17 and 19. The results of C-banding suggested that the fused chromosome is dicentric. The translocation was traced back through two generations and occurred in a total of 8 of 62 animals in the herd.     

Reproductive studies of the Oryx

The genus Oryx comprises one species already extinct in the wild and others that are rapidly disappearing. It is important to understand the reproductive physiology of these species in order to ensure their successful captive propagation. It was determined behaviorally and hormonally that the scimitar-horned oryx's 21–22 d estrous cycle very closely resembled that of the domestic cow. Four females of three species (Arabian, scimitar-horned, and fringe-eared oryx) were treated with prostaglandin (PG) and pregnant mares serum gonadotropin (PMSG) or follicle-stimulating hormone (FSH). All animals responded to prostaglandin treatment with shortened cycles and behavioral estrus. Ovulation occurred in all females but only one responded to gonadotrophin treatment with a mild superovulation. An embryo recovered from an Arabian oryx was frozen in liquid nitrogen for 6 months. Upon thawing, the normal-appearing morula was surgically transferred to a scimitar-horned oryx. The recipient failed to carry the embryo and returned to estrus within three weeks of the transfer. It was demonstrated that induction of ovulation and synchronization of estrus can be achieved in the three Oryx species with PMSG or FSH combined with prostaglandin treatment.     

Hematological and serum chemistry values for Arabian oryx (Oryx leucoryx)

Blood samples obtained from 73 captive Arabian oryx (Oryx leucoryx) were analyzed for hematology and serum chemistry values. Compared with other data from this animal RBC, WBC, bilirubin and ASAT values are lower, but glucose, urea and uric acid values are higher.     

Activity re-assignment and microclimate selection of free-living Arabian oryx: responses that could minimise the effects of climate change on homeostasis?

Predicting whether behaviour could buffer the effects of climate change on long-lived mammals requires a better understanding of the long-term behavioural responses of mammals to environmental stress. Using biologging, we measured locomotor activity and microclimate selection, over eight months, in five Arabian oryx (Oryx leucoryx) living free in a Saudi Arabian desert. The oryx displayed seasonal flexibility in activity patterns, shifting from a continuous 24-h activity pattern with crepuscular peaks in cooler months to a predominantly nocturnal activity pattern during the hottest months, without reducing the total 24-h activity level. The proportion of total 24-h activity that occurred during daylight hours was just 29 ± 8% during the hottest months, versus 53 ± 8% (mean ± SD, n = 5 oryx) in the other months. The attenuation in diurnal activity levels during the hot months was accompanied by the selection of cooler microclimates, presumably via shade seeking, during the heat of the day. Analysis of miniature black globe (miniglobe) temperature from a remote sensor on the collar of two female animals revealed that oryx selected microclimates cooler than the microclimates in direct sun at higher environmental heat loads across all periods, but with enhanced efficiency during the dry periods. We have quantified activity re-assignment and microclimate selection as responses to hot arid conditions in a free-living artiodactyl. Such flexible behavioural processes may act to buffer the adverse effects of the progressively hotter and drier conditions predicted to occur with climate change.     

Variation in the daily rhythm of body temperature of free-living Arabian oryx (Oryx leucoryx): does water limitation drive heterothermy?

Heterothermy, a variability in body temperature beyond the limits of homeothermy, has been advanced as a key adaptation of Arabian oryx (Oryx leucoryx) to their arid-zone life. We measured body temperature using implanted data loggers, for a 1-year period, in five oryx free-living in the deserts of Saudi Arabia. As predicted for adaptive heterothermy, during hot months compared to cooler months, not only were maximum daily body temperatures higher (41.1 ± 0.3 vs. 39.7 ± 0.1°C, P = 0.0002) but minimum daily body temperatures also were lower (36.1 ± 0.3 vs. 36.8 ± 0.2°C, P = 0.04), resulting in a larger daily amplitude of the body temperature rhythm (5.0 ± 0.5 vs. 2.9 ± 0.2°C, P = 0.0007), while mean daily body temperature rose by only 0.4°C. The maximum daily amplitude of the body temperature rhythm reached 7.7°C for two of our oryx during the hot-dry period, the largest amplitude ever recorded for a large mammal. Body temperature variability was influenced not only by ambient temperature but also water availability, with oryx displaying larger daily amplitudes of the body temperature rhythm during warm-dry months compared to warm-wet months (3.6 ± 0.6 vs. 2.3 ± 0.3°C, P = 0.005), even though ambient temperatures were the same. Free-living Arabian oryx therefore employ heterothermy greater than that recorded in any other large mammal, but water limitation, rather than high ambient temperature, seems to be the primary driver of this heterothermy.     

Does size matter? Comparison of body temperature and activity of free-living Arabian oryx (<Emphasis Type="Italic">Oryx leucoryx</Emphasis>) and the smaller Arabian sand gazelle (<Emphasis Type="Italic">Gazella subgutturosa marica</Emphasis>) in the Saudi desert

Heterothermy, a variability in body temperature beyond the normal limits of homeothermy, is widely viewed as a key adaptation of arid-adapted ungulates. However, desert ungulates with a small body mass, i.e. a relatively large surface area-to-volume ratio and a small thermal inertia, are theoretically less likely to employ adaptive heterothermy than are larger ungulates. We measured body temperature and activity patterns, using implanted data loggers, in free-ranging Arabian oryx (Oryx leucoryx, ±70 kg) and the smaller Arabian sand gazelle (Gazella subgutturosa marica, ±15 kg) inhabiting the same Arabian desert environment, at the same time. Compared to oryx, sand gazelle had higher mean daily body temperatures (F _1,6 = 47.3, P = 0.0005), higher minimum daily body temperatures (F _1,6 = 42.6, P = 0.0006) and higher maximum daily body temperatures (F _1,6 = 11.0, P = 0.02). Despite these differences, both species responded similarly to changes in environmental conditions. As predicted for adaptive heterothermy, maximum daily body temperature increased (F _1,6 = 84.0, P < 0.0001), minimum daily body temperature decreased (F _1,6 = 92.2, P < 0.0001), and daily body temperature amplitude increased (F _1,6 = 97.6, P < 0.0001) as conditions got progressively hotter and drier. There were no species differences in activity levels, however, both gazelle and oryx showed a biphasic or crepuscular rhythm during the warm wet season but shifted to a more nocturnal rhythm during the hot dry season. Activity was attenuated during the heat of the day at times when both species selected cool microclimates. These two species of Arabian ungulates employ heterothermy, cathemerality and shade seeking very similarly to survive the extreme, arid conditions of Arabian deserts, despite their size difference.     

Major histocompatibility complex variation in the Arabian oryx

In the 1960s, the Arabian oryx was one of the most endangered species in the world, extinct in the wild and surviving in only a few captive herds. The present day population of over 2000 descends from a small number of founders and may have restricted genetic variation for important adaptive genes. We have examined the amount of genetic variation for a class II gene in the major histocompatibility complex thought to be the most important genetic basis for pathogen resistance in vertebrates. We found three very divergent alleles, which on average, differed by 24 nucleotides and 15 amino acids in the 236-bp fragment we examined. Using single-strand conformation polymorphism, we found that in a sample of 57 animals, the alleles were in Hardy-Weinberg proportions, although one allele was found only in four heterozygous individuals. The average heterozygosity for the 22 amino acid positions involved in antigen binding was 0.165, three times as high as that for the 56 amino acids not involved with antigen binding. Because the three alleles have such divergent sequences, it is likely that they may recognize peptides from quite different pathogens. As a result, maintenance of these variants should be considered as a goal in the captive breeding program of the Arabian oryx.     

Physiological acclimation of a desert antelope, Arabian oryx (Oryx leucoryx), to long-term food and water restriction

Desert mammals often experience scarcity of drinking water and food for prolonged periods. In this study, the first long-term acclimation experiment in a non-domesticated desert-adapted ungulate, we investigated the mechanisms used by the Arabian oryx Oryx leucoryx, to adjust its physiology to progressive food and water restriction over 5 months, an experimental regimen and time course chosen to mimic what it typically experiences between spring and late summer in the desert. At the end of the acclimation period, oryx consumed less than one and half of food and water of animals in the control group and lost 8.2±2.6% of their initial body mass. Experimental animals reduced their mass-specific resting metabolic rate (RMR) and total evaporative water loss (TEWL) by 16.2 and 25.7%, respectively, and maintained a digestive efficiency of about 70%. We found no support for the idea that reduced RMR in oryx correlated with a decreased thyroid hormone concentration in plasma. At the end of the 5 months acclimation, oryx continued to mobilize fatty acids to fuel metabolism, and did not use protein breakdown as a major source of gluconeogenesis. Oryx in the experimental group reduced their water intake by 70% and maintained constant plasma osmolality. They adjusted their water budget by reducing mass-specific TEWL, increasing urine osmolality and reducing urine volume by 40%, and excreting feces with <50% water content. Oryx have an unusually low TEWL compared with other arid-zone ungulates; both hydrated and water-deprived individuals have TEWL values, 51.7 and 39.3%, respectively, of allometric predictions for arid-zone ungulates. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.     

Species-specific sperm-egg interaction affects the utility of a heterologous bovine in vitro fertilization system for evaluating antelope sperm

The purpose of this study was to evaluate cryopreserved fringe-eared (FE) oryx (Oryx gazella callotis) sperm function using a heterologous in vitro fertilization (IVF) system previously developed to study scimitar-horned (SH) oryx (Oryx dammah) spermatozoa. Semen was collected by electroejaculation from FE oryx (n = 2) and SH oryx (n = 2), evaluated immediately postcollection, and cryopreserved. Thawed spermatozoa were evaluated for motility, forward progression, and acrosomal status immediately post-thaw, after Percoll-separation, and 1, 2, 3, and 8 h after culture in IVF medium. In vitro-matured cow oocytes (n = 924) were inseminated with either domestic bull, FE, or SH oryx spermatozoa and after an 8-h coincubation period, half the oocytes were fixed and examined for sperm penetration, polyspermy, and male pronuclear formation. The remaining oocytes were placed into in vitro culture and evaluated for cleavage after 48 h. Overall, there were no between-species differences in sperm motility and acrosome integrity. However, an effect of time (P < 0.05) and a species-by-time interaction (P < 0.05) were detected for both parameters. Penetration, male pronuclear formation, and embryo cleavage were high (>90%, >85%, and >70%, respectively) for oocytes inseminated with domestic bull and SH oryx spermatozoa and did not differ (P > 0.05) between species. In contrast, very few oocytes (2.8%, 4 of 141) inseminated with FE oryx sperm were penetrated. Cleavage was rare (8.0%, 16 of 200) in oocytes inseminated with FE oryx spermatozoa and did not differ (P > 0.05) from that in parthenogenetic controls (4.2%, 3 of 72). Furthermore, FE oryx spermatozoa were incapable of penetrating zona-free cow oocytes. These results indicate that species-specific differences in gamete interaction may exist even between very closely related nondomestic bovids.     

A comparison of the genome organization of capripoxvirus with that of the orthopoxviruses.

Comprehensive comparisons of genome organizations for poxviruses of different genera have not previously been reported. Here we have made such a comparison by cross-hybridizing genome fragments from capripoxvirus KS-1 and vaccinia virus WR (VV). This showed that a 100- to 115-kilobase (kb) centrally placed section is essentially colinear in organization in the two viruses and that a small region has translocated between the ends of one or other of the genomes during their divergence. No cross-hybridization could be detected between VV DNA and the respective left- and right-hand terminal 8 and 25 kb of capripoxvirus DNA or between capripoxvirus DNA and the respective left- and right-hand terminal 38 and 35 kb of VV DNA. By using the cross-hybridization data, a 4-kb fragment of KS-1 DNA was identified, which corresponds to the regions of the cowpox virus and VV genomes containing genes for the orthopoxvirus A-type inclusion body protein ("ATI"). The sequence of the KS-1 DNA fragment contains homologs of genes which are on either side of the orthopoxvirus ATI genes but contains no homolog of the ATI gene itself. Overall, these results show that the pattern of genomic conservation and variation between two poxvirus genera reflects the pattern within the orthopoxvirus genus but that, as observed previously, individual genes may not be present in genomic regions which are otherwise conserved in organization.