Agonistic interactions and social behaviors in the Saharan Dorcas gazelle (Gazella dorcas neglecta): Using social network analysis to evaluate relationships and social structure in captive male groups.

Social interactions, including agonistic behavior, are very important for the management and welfare of individuals forming groups in captivity. One of the main concerns for the stability and durability of adult male groups is a noticeable level of intraspecific aggression. This study comprises a Social Network Analysis to illustrate social structure in different groups of captive Saharan Dorcas gazelles (Gazella dorcas neglecta). Our main objectives were to examine the relationship between agonistic, affiliative, and association networks and their reciprocity, assessing also whether the agonistic networks can conform to a linear dominance hierarchy. For these purposes, we recorded the behavior of 23 adult males organized in five herds, three composed only of Saharan Dorcas gazelle males and two mixed herds in which there were also Mhorr gazelle males (Nanger dama mohor). Observations were carried out during 295 h through scan sampling. We found no correlation between the affiliative and association networks in any group, although there was a significant correlation between the agonistic and association networks in mixed-species groups which was not present in single-species groups. Overall, there was no consistent reciprocity in either affiliative nor agonistic networks and none of the agonistic networks showed a linear structure. These results indicate that affiliative behavior in Saharan Dorcas gazelles offers distinctive and valuable information about the bonds between individuals, however, their dominance structure is far more complex than previously thought. As information provided by affiliative and proximity behaviors is different in this species, we suggest considering affiliative interactions to stablish affinity between individuals. Evaluating different social behaviors and not only agonistic interactions in later studies, is also recommended to develop a more accurately daily management in zoos that guarantee group stability and individuals' welfare, which will improve the conservation of captive populations.

Feeding Ecology of the Cuvier's Gazelle (Gazella cuvieri, Ogilby, 1841) in the Sahara Desert.

Knowledge of the feeding ecology of ungulates in arid biomes offers an interesting model for understanding the drought resistance of large desert-adapted herbivores, a crucial issue in the face of increasing desertification due to climate change. To assess the feeding ecology of the endangered Cuvier's gazelle (Gazella cuvieri) in the Sahara desert, we used a multi-method approach combining faecal samples, direct observations, and the recording of indirect signs of feeding. We hypothesised that browser behaviour is the best foraging strategy for species living in hyper-arid environments, mainly due to long periods without grazing opportunities. Complementarily, we explored the effects of the main environmental descriptors (rainfalls and NDVI) on feeding patterns and diet quality. We found that Cuvier's diets are based mainly on acacias (Vachellia tortilis, V. flava) and occasionally on the annual forb Anastatica hierochuntica. In total, eighteen species (five trees, nine shrubs, three herbs, and one grass) belonging to fifteen families were recorded. Our result confirmed the browsers' characteristic of this species, reaffirming its ability to settle in a hostile environment. Acacias stand out as key species consumed at the southernmost limit of their range; hence, future conservation plans and strategies should take this into account for the survival of Cuvier's gazelle in desert environments.

Publisher Correction: Identifying priority conservation areas in a Saharan environment by highlighting the endangered Cuvier's Gazelle as a flagship species.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Identifying priority conservation areas in a Saharan environment by highlighting the endangered Cuvier's Gazelle as a flagship species.

Monitoring populations and designing effective conservation actions for endangered species present significant challenges. An accurate understanding of current distribution, ecological traits and habitat requirements is imperative in formulating conservation strategies. Recent surveys on the southernmost Cuvier's Gazelle (Gazella cuvieri) population, an ungulate endemic to North Africa, showcase its importance in terms of numbers and genetic diversity. This population inhabits a remote region in the extreme north-western portion of the Sahara Desert and has not been well studied. Here, we examine the potential distribution of Cuvier's Gazelle and the environmental factors limiting the species in a Saharan environment, by combining broad-scale field survey data and species distribution models. Our objective was to identify high priority conservation areas in the southernmost known portion of the species' distribution by modelling habitat selection at the landscape scale using a predictive distribution map. Our results show that the distribution of Cuvier's Gazelle is strongly related to mountainous areas with heterogeneous terrain and remoteness from large human settlements over other ecological factors that had less impact on the species' presence and distribution. We also provide a quantitative estimate of the potential distribution range of Cuvier's Gazelle in southern Morocco, identifying two well-demarcated key areas. The two core areas currently contain enough rugged terrain isolated from human encroachment to support the endangered species in this harsh desert environment. We encourage the implementation of conservation planning for Cuvier's Gazelle as an "umbrella species", which will confer effective protection to higher-quality habitat zones and co-occurring species, leading to sustainable and ecologically responsible development in the region.

Using Farm Animal Welfare Protocols as a Base to Assess the Welfare of Wild Animals in Captivity-Case Study: Dorcas Gazelles (Gazella dorcas).

There is a lack of protocols specifically developed for the assessment of welfare of wild animals in captivity, even when it is known that providing good standards of welfare is important. The aim of this study was the development and the application of a protocol for the assessment of welfare in captive dorcas gazelles. The protocol was mainly developed taking into account the protocol for the assessment of welfare in cattle from the Welfare Quality® project, the available literature of the biology of this species and the Husbandry Guidelines developed for captive breeding and management of this species. The protocol was specifically developed for dorcas gazelles and included four principles, 10 criteria and 23 animal and environmental-based indicators. To test its utility, this protocol was applied to five different groups of gazelles from three different zoos. Its application made possible to detect areas for improvement in all groups assessed.

Aggressive behavior and hair cortisol levels in captive Dorcas gazelles (Gazella dorcas) as animal-based welfare indicators.

Ensuring welfare in captive wild animal populations is important not only for ethical and legal reasons, but also to maintain healthy individuals and populations. An increased level of social behaviors such as aggression can reduce welfare by causing physical damage and chronic stress to animals. Recently, cortisol in hair has been advanced as a non-invasive indicator to quantify long-lasting stress in many species. The sensitivity of social behavior and hair cortisol concentration was evaluated in several groups of dorcas gazelles (Gazella dorcas). Four different groups of gazelles from three different zoos were observed and the expression of intra-specific affiliative and negative social behaviors was assessed across the different groups. Hair samples were taken from sub-groups of animals and analyzed for cortisol concentrations. Significant differences between groups of dorcas gazelles were found in frequency of negative social behavior and hair cortisol concentration. Despite the low sample size, these two parameters had a positive Spearman correlation coefficient (rs = +0.80, P = 0.20). These results suggest that hair cortisol levels are sensitive to differences in the social structure of dorcas gazelles. Zoo Biol. 35:467-473, 2016. © 2016 Wiley Periodicals, Inc.

Genetic identification of endangered North African ungulates using noninvasive sampling.

North African ungulates include several threatened and emblematic species, yet are poorly studied mainly due to their remoteness and elusiveness. Noninvasive sampling provides a useful approach to obtain ecological and genetic information essential to guide conservation actions. The very first and most important step in conservation planning is to accurately identify species, and molecular genetics has been proved to be a useful tool. Several molecular genetics protocols are available for species identification, even for samples with poor quality DNA, such as faeces, hairs or bones. Most of these protocols use mitochondrial DNA for barcoding despite this marker being especially prone to problems, including mtDNA introgression, nuclear insert copies, high intraspecific diversity or heteroplasmy. In this work, we developed a molecular method based on polymorphisms in small fragments of the mitochondrial cytochrome b (cytb, mtDNA) and the nuclear kappa casein genes (KCAS, nDNA) for identifying endangered North African ungulates. These fragments revealed polymorphisms, including species-specific variation, which allowed species identification of nine ungulate species that co-occur in North Africa. The method was validated across more than 400 samples, including different types of noninvasive samples collected in the field. The simplicity, high reliability and relative low cost of the described method make it a promising tool to improve ecological studies of the North African ungulates and consequently, the implementation of more efficient management and conservation plans for these endangered ungulates.

Splitting or lumping? A conservation dilemma exemplified by the critically endangered dama gazelle (Nanger dama).

Managers of threatened species often face the dilemma of whether to keep populations separate to conserve local adaptations and minimize the risk of outbreeding, or whether to manage populations jointly to reduce loss of genetic diversity and minimise inbreeding. In this study we examine genetic relatedness and diversity in three of the five last remaining wild populations of dama gazelle and a number of captive populations, using mtDNA control region and cytochrome b data. Despite the sampled populations belonging to the three putative subspecies, which are delineated according to phenotypes and geographical location, we find limited evidence for phylogeographical structure within the data and no genetic support for the putative subspecies. In the light of these data we discuss the relevance of inbreeding depression, outbreeding depression, adaptive variation, genetic drift, and phenotypic variation to the conservation of the dama gazelle and make some recommendations for its future conservation management. The genetic data suggest that the best conservation approach is to view the dama gazelle as a single species without subspecific divisions.

Characterization of the estrous cycle and reproductive traits of the aoudad (Ammotragus lervia) in captivity.

In this study the estrous cycle of the aoudad has been analyzed and characterized for the first time, using non-invasive methods for tracking reproductive cyclicity. The duration of the estrous cycle is 23 days (range 16-32 days), with a luteal phase of 17 days (range 12-27 days) and an interluteal phase of 6 days (range 3-14 days). The estrous cycle did not differ between females, but it was affected by the time of the year. Intraindividual variation of the cycle was observed in one out of the nine individuals. The average hormone concentration values, the estrogen:progestogen ratio, as well as their minimum and maximum values for each interluteal and luteal phases of the estrous cycle, are shown. Interindividual differences found in these values were basically associated with age. Females tended to start their cycle when in the presence of an adult male. Anestrus was observed in study females except for the oldest (14 years old). Age and anestrus onset were correlated, with younger females starting earlier than the older ones. This study reveals that Ammotragus reproductive biology is more similar to that of Capra than Ovis, except for some endocrinological features.

Trajectory variance and autocorrelations within single-sperm tracks as population-level descriptors of sperm track complexity, predictability, and energy-generating ability.

The objectives of the present study were to develop an alternative theoretical approach to the analysis of sperm motility and to develop motility parameters that would complement those more commonly used in current computer-assisted semen analysis procedures. We have defined a set of parameters and have tested them using boar spermatozoa undergoing bicarbonate-induced motility activation. The new parameters were calculated for a series of (x,y) coordinates of sperm head positions recorded at each move along the trajectory. The parameters were: mean velocity (MV), immobility ratio, fractal dimension (FD), the variance of the steplengths (VAR), and 2 autocorrelation function coefficients of the step-length time series for lags 1 and 2 (C(1) and C(2)). MV measures the average speed along the trajectory, and VAR is a measure of displacement variability that can be related to the specific mean (per step) kinetic energy of the spermatozoon. All of the parameters except MV and FD were affected by the sampling frequency (25 vs 50 Hz); inappropriately high sampling frequency in relation to magnification resulted in step-lengths between successive frames that were below the resolution threshold of the imaging system. The autocorrelation functions were especially informative; discrimination between sperm subpopulations was obvious within simple histogram formats, and complex statistical analyses were not needed for their identification.

Applications and interpretation of computer-assisted sperm analyses and sperm sorting methods in assisted breeding and comparative research.

Theoretical and practical knowledge of sperm function is an essential requirement in almost every aspect of modern reproductive technology, if the overarching objective is the eventual production of live offspring. Artificial insemination (AI) techniques depend on the availability of high quality semen, whether fresh, diluted and stored, or frozen. Assessing such semen for quality and the likelihood of fertility is therefore also important, as much time, resources and effort can easily be wasted by using poor samples. Some semen technologies are aimed not at quality assessment, but at attempting to skew the breeding outcomes. Sex preselection by separating the male- and female-bearing spermatozoa using flow cytometry is now practised routinely in the agricultural industry, but speculatively it may eventually be possible to use other genetic markers besides the sex chromosomes. A moment's reflection shows that although sex-biasing flow cytometry technology is well developed and generally fulfils its purpose if presorting of sperm quality is adequate, other technologies aimed specifically at semen assessment are also sophisticated but provide inadequate data that say little about fertility. This is especially true of instrumentation for objective sperm motility assessment. Here we aim to examine this technological paradox and suggest that although the sperm assessment equipment might be sophisticated, the shortcomings probably lie largely with inappropriate objectives and data interpretation. We also aim to review the potential value and use of sperm sexing technology for non-domestic species, arguing in this case that the limitations also lie less with the technology itself than with the applications envisaged. Finally, the potential application of a sorting method directed at motility rather than sperm DNA content is discussed.

Output of gastrointestinal nematode eggs in the feces of captive gazelles (Gazella dama mhorr, Gazella cuvieri and Gazella dorcas neglecta) in a semiarid region of southeastern Spain.

Feces from 62 captive African gazelles, including Mhorr gazelles (Gazella dama mhorr), Cuvier's gazelles (Gazella cuvieri), and Dorcas gazelles (Gazella dorcas neglecta), were examined over the course of a year to quantitate nematode egg excretion patterns. Strongyloides sp. eggs appeared only in G. dama during the rainy season. Trichostrongylidae egg excretion showed a marked seasonal variation, with very low levels during the dry and hot period, a finding that is probably attributable to hypobiosis of the predominant species (Camelostrongylus mentulatus). Eggs of the Nematodirus sp., predominantly Nematodirus spathiger, were excreted throughout the year. No seasonal pattern was observed in Trichuris sp. egg excretion.

Kinematic changes during the cryopreservation of boar spermatozoa.

The present study evaluates the effect that various steps of a conventional cycle of cryopreservation have on the patterns of movement exhibited by boar spermatozoa. Sperm-rich ejaculate fractions collected from 24 mature fertile boars (1 ejaculate per boar) were cryopreserved following a standard freeze-thaw procedure with 0.5-mL plastic straws. Overall sperm motility and the individual kinematic parameters of motile spermatozoa (assessed by the computer-aided sperm analysis system Sperm Class Analyzer [SCA]) were recorded in 5 steps of the cryopreservation procedure. These steps were as follows: 1) at the time that the fresh semen was extended, 2) at 17 degrees C, after sperm concentration by centrifugation and re-extension of the pellet with lactose-egg yolk extender; 3) at 5 degrees C, after added freezing extender; 4) at the time that thawed semen was held in a water bath at 37 degrees C for 30 minutes; and 5) at the time that thawed semen was held in a water bath at 37 degrees C for 150 minutes. Data from individual motile spermatozoa, defined by 7 kinematic parameters (curvilinear velocity [VCL], straight-line velocity [VSL], average path velocity [VAP], linearity [LIN], straightness [STR], mean amplitude of lateral head displacement [ALH], and beat cross frequency [BCF]), were analyzed using a pattern analysis technique (PATN) to identify and quantify populations and subpopulations of motile sperm within the semen samples. After the first cluster analysis, 3 motile sperm populations (P) were identified (P1: progressive and/or vigorous cells [90.4%], P2: poorly progressive cells [8.3%], and P3: nonprogressive cells [1.3%]). These populations remained constant (P > .05) throughout the 5-step cryopreservation procedure. A second PATN was carried out within the P1 sperm population, which identified 3 sperm subpopulations (sP) (eg, sP1: cells with progressive and vigorous movement [58.7%], sP2: progressive cells only [24.6%], and sP3: vigorous cells only, hyperactive-like [16.7%]). Although the relative frequency of these 3 subpopulations varied among ejaculates (boars), there was no interaction with any cryopreservation step we examined. Whereas sP1 remained constant (P > .05), sP2 and sP3 varied significantly (P < .05) through the cryopreservation procedure, with the increase in sP3 after centrifugation at 17 degrees C and during cooling at 5 degrees C considered particularly relevant. In conclusion, the present study confirms the heterogeneity of sperm movement patterns in boar semen, patterns that vary through the cryopreservation procedure, especially after removal of the seminal plasma by centrifugation and subsequent extension at 17 degrees C and after the slow cooling at 5 degrees C, when obvious increases in hyperactivated movement appeared. The vast majority of spermatozoa, those exhibiting progressive and vigorous movement, remained constant during the cryopreservation procedure, although the proportion differed among boars.

Endocrine correlates of sexual behavior in the Mohor gazelle (Gazella dama mhorr).

In this study, we quantitatively examined male sexual behavior in relation to fecal estrogen and progesterone concentrations in female Mohor gazelles. We investigated the hypothesis that, during natural mating, males detect cues relating to the potential for successful conception and pregnancy. Time series analysis revealed that males could detect the approach of estrus 2-3 days before female fecal estrogens and estrogen/progestagen (E/P) ratio reached their peak values. Males also paid closer attention to those females excreting higher fecal estrogen concentrations. Mounting and copulation frequencies were positively correlated with both peri-ovulatory fecal estrogen concentrations, and the frequency of pre-copulatory courtship behaviors. These data suggested that males invest their reproductive effort selectively by mating the most fertile females, assuming that estrogen is a valid index of fertility. This assumption was investigated by examining sequential phases of the reproductive cycle for evidence that oocytes and follicles produced in a more estrogenic environment would lead to the formation of the most competent corpora lutea, thereby maximizing the chance of sustaining pregnancy. Associations between sexual behavior and hormone excretion support the hypothesis that males may use this mechanism to assess female fertility.