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1.
We examine the muscle fiber population of skeletal muscles from whole body in the cheetah (Acinonyx jubatus). In the present experiments, we showed the characteristics of fiber composition in the cheetah by comparative studies among the cheetah, domestic cat, and the beagle dog. Fiber population was determined on muscle fibers stained with monoclonal antibody to each myosin heavy chain isoform. Histochemical analysis demonstrated that many muscles in the cheetah and domestic cat had a low percentage of Type I fibers and a high percentage of Type IIx fibers, while those in the beagle dog showed a high percentage of Type IIa. The hindlimb muscles in the cheetah had a higher percentage of Type II (Type IIa + IIx) fiber than the forelimb muscles. This fact suggests that the propulsive role of the hindlimb is greater than the forelimb in the cheetah. The longissimus in the cheetah had a high percentage of Type IIx fibers over a wide range from the thoracic to lumbar parts, while the population of muscle fibers in this muscle was different depending on the parts in the domestic cat and beagle dog. This indicates that the cheetah can produce a strong and quick extension of the spinal column and increase its stiffness during locomotion. Furthermore, we found the notable difference of muscle fiber type population between flexors and extensors of digits in the cheetah. The present experiments show the characteristics of muscle fibers in the cheetah, corresponded to its ability to perform high-speed running.  相似文献   

2.
The African cheetah (Acinonyx jubatus) is an unusual species because of its extremely low amount of biochemical genetic variation. A comparative analysis of morphological variation of 16 cranial characters from four species of Felidae (ocelot, Leopardus pardalus; margay, L. wiedii; leopard, Panthera pardus; and cheetah) was undertaken to evaluate the consequence of biochemical monomorphism on morphological variation. The species were selected because the cheetah has been shown previously to possess extremely low amounts of biochemical genetic variation as opposed to the other three species which retain comparatively high levels of allozyme heterozygosity. The cheetah sample showed dramatically greater fluctuating asymmetry but was not outstanding in morphological variability. Elevated levels of fluctuating asymmetry have been interpreted as a reflection of developmental instability, which is a common consequence of inbreeding. The inverse correlation of genetic variation and developmental stability (homeostasis) observed here fulfills prior expectations and further emphasizes the genetic invariability of the cheetah species.  相似文献   

3.
Assessing trends in abundance and density of species of conservation concern is vital to inform conservation and management strategies. The remaining population of the cheetah (Acinonyx jubatus) largely exists outside of protected areas, where they are often in conflict with humans. Despite this, the population status and dynamics of cheetah outside of protected areas have received relatively limited attention across its range. We analyzed remote camera trapping data of nine surveys conducted from 2005 to 2014 in the Waterberg Conservancy, north-central Namibia, which included detections of 74 individuals (52 adult males, 7 adult females and 15 dependents). Using spatial capture–recapture methods, we assessed annual and seasonal trends in cheetah density. We found evidence of a stable trend in cheetah density over the study period, with an average density of 1.94/100 km2 (95% confidence interval 1.33–2.84). This apparent stability of cheetah density is likely the result of stable and abundant prey availability, a high tolerance to carnivores by farmers and low turnover rates in home range tenure. This study highlights the importance of promoting long-term surveys that capture a broad range of environmental variation that may influence species density and the importance of nonprotected areas for cheetah conservation.  相似文献   

4.
The cheetah (Acinonyx jubatus) is listed as a vulnerable species by the International union for the conservation of nature (IUCN), including two critically endangered subspecies, the Saharan cheetah, and the Iranian cheetah, so it is imperative that we understand variation in cheetah morphology to make good decisions regarding the conservation of this species. Here, we aim to determine whether northeastern African cheetahs have smaller body sizes than southern African cheetahs. This study also adds to our knowledge of cheetah morphology from two cheetah populations that do not yet have comprehensive published data: Kenya, and northeastern Africa, including captive individuals. We calculated means and standard deviations on cranial and body measurements of live or in few cases, freshly dead, cheetahs from the aforementioned populations, plus previously published data on Namibian and Botswanan cheetahs and compared them to one another using multivariate analysis of variance. Results show that northeastern African cheetahs have smaller body sizes than southern and eastern African populations. We also found that captive cheetahs retain the morphological characteristics of their ancestral population- captive cheetahs from southern Africa have similar body sizes to wild southern African cheetahs and larger body sizes than captives from northeastern Africa. Other analyses regarding cheetah growth agree with previous studies on Namibian and Botswanan cheetah populations rates. As such, this study can serve as a baseline for the care of captive cheetah populations to maintain healthy weights and body proportions.  相似文献   

5.
Camera trapping studies have become increasingly popular to produce population estimates of individually recognisable mammals. Yet, monitoring techniques for rare species which occur at extremely low densities are lacking. Additionally, species which have unpredictable movements may make obtaining reliable population estimates challenging due to low detectability. Our study explores the effectiveness of intensive camera trapping for estimating cheetah (Acinonyx jubatus) numbers. Using both a more traditional, systematic grid approach and pre-determined, targeted sites for camera placement, the cheetah population of the Northern Tuli Game Reserve, Botswana was sampled between December 2012 and October 2013. Placement of cameras in a regular grid pattern yielded very few (n = 9) cheetah images and these were insufficient to estimate cheetah density. However, pre-selected cheetah scent-marking posts provided 53 images of seven adult cheetahs (0.61 ± 0.18 cheetahs/100km²). While increasing the length of the camera trapping survey from 90 to 130 days increased the total number of cheetah images obtained (from 53 to 200), no new individuals were recorded and the estimated population density remained stable. Thus, our study demonstrates that targeted camera placement (irrespective of survey duration) is necessary for reliably assessing cheetah densities where populations are naturally very low or dominated by transient individuals. Significantly our approach can easily be applied to other rare predator species.  相似文献   

6.
Large terrestrial carnivores especially have experienced substantial declines in range and numbers. Changes in land use are a main driver of such declines, yet various developing countries have accelerated land use change through state-led land reform programmes. One of the most renowned land reform programmes is Zimbabwe’s fast track land reform programme (FTLRP), which resulted in fast and compulsory subdivision of large commercial farms into indigenized small scale commercial and subsistence farms. Several case studies have shown an impact of the FTLRP on wildlife, however, its effect on wildlife populations at a nationwide scale remains largely unknown. Due to its wide-ranging nature, the cheetah (Acinonyx jubatus) is particularly vulnerable to changes in land use. In this study I used questionnaire survey and citizen science data to determine the population status and distribution of the cheetah 15 years after introduction of the FTLRP. I also assessed the level of human-cheetah conflict, and attitudes of commercial and subsistence farmers towards cheetah. I found dramatic range contractions and population declines, particularly in the landscape outside protected areas. Despite minimal conflict, subsistence farmers were less tolerant to cheetah than commercial farmers. Consequently, land reform is likely to have increased the hostility of the cheetah landscape outside protected areas. This study is one of the most comprehensive species assessments to date. It provides valuable empirical data on the implications of land use change and emphasizes how a lack of knowledge impedes our ability to recognize a species vulnerability to (local) extinction risk.  相似文献   

7.
Eighty-nine per cent, of 136 cheetah kills in the Serengeti National Park consisted of Thomson's gazelles, the most abundant and readily available species in the size category (60 kg or less) preferred by the cheetah. Fifty-four per cent, of the Thomson's gazelle kills were subadult; among the adults all age classes were represented. One female cheetah captured 24 Thomson's gazelles in 26 days, a killing rate of 10 kg/day. The actual food intake of this female was about 4 kg/day. The hunting success of cheetah pursuing large subadult and adult Thomson's gazelles was about 50 per cent. The hunting methods–including the various means of approaching prey–are described as are the typical ways of killing and feeding. Twelve per cent, of the cheetah kills were appropriated by lions and hyaenas.  相似文献   

8.
Sperm-oocyte interaction in vitro was studied in the cheetah, a species known to produce poor quality ejaculates and to experience low rates of fertility. Twelve female cheetahs were injected (i.m.) with eCG followed by hCG 84 h later. Twenty-four to 26 h post hCG, each was subjected to laparoscopic oocyte aspiration. A sperm motility index (SMI) was calculated for each of 9 cheetah sperm donors that produced ejaculates averaging 41.3 +/- 22.9 x 10(6) motile sperm and 28.4 +/- 4.9% structurally normal sperm. Each ejaculate was used to inseminate cheetah oocytes from 1 or 2 females and salt-stored, domestic cat oocytes. The presence of ovarian follicles (greater than or equal to 1.5 mm in diameter) showed that all females responded to exogenous gonadotropins (range, 11-35 follicles/female). A total of 277 cheetah oocytes was collected from 292 follicles (94.9% recovery; 23.1 +/- 2.2 oocytes/female). Of these, 250 (90.3%) qualified as mature and 27 (9.7%) as degenerate. Of the 214 mature oocytes inseminated, 56 (26.2%) were fertilized, and 37 (17.3%) cleaved to the 2-cell stage in vitro; but the incidence of in vitro fertilization (IVF) varied from 0 to 73.3% (p less than 0.001) among individual males. When oocytes from individual cheetahs (n = 5) were separated into two groups and inseminated with sperm from a male with an SMI greater than 0 after 6 h coincubation versus an SMI = 0 at this time, the mean fertilization rates were 28/44 (63.6%) and 0/37 (0%), respectively (p less than 0.05). Of the 117 domestic cat oocytes coincubated with cheetah sperm, 96.6% contained 1 or more cheetah sperm in the outer half of the zona pellucida (ZP). Although the mean number of cheetah sperm penetrating the outer ZP of the cat oocyte was similar (p greater than 0.05) among all males, there was a positive correlation between the number of sperm reaching the inner half of the ZP and fertilization rate in vitro (r = 0.82; p less than 0.05). Compared to IVF efficiency in the domestic cat and tiger as reported in earlier studies, IVF efficiency in the cheetah is low. Because oocytes from 11 of 12 cheetahs were fertilized in vitro, there is no evidence that the female gamete is incompetent. Although sperm pleiomorphisms may contribute to poor reproductive performance, examination of the data on the basis of individual sperm donors reveals that effective gamete interaction in the cheetah is dictated, in part, by sperm motility.  相似文献   

9.
This case report describes a multicentric lymphoma in a 4 yr old female wildborn captive cheetah (Acinonyx jubatus) in Namibia after being housed in an enclosure adjacent to a feline leukemia virus (FeLV) infected cheetah that had previously been in contact with domestic cats. The year prior to the onset of clinical signs, the wild-born cheetah was FeLV antigen negative. The cheetah subsequently developed lymphoma, was found to be infected with FeLV, and then rapidly deteriorated and died. At necropsy, the liver, spleen, lymph nodes, and multiple other organs were extensively infiltrated with neoplastic T-lymphocytes. Feline leukemia virus DNA was identified in neoplastic lymphocytes from multiple organs by polymerase chain reaction and Southern blot analysis. Although the outcome of infection in this cheetah resembles that of FeLV infections in domestic cats, the transmission across an enclosure fence was unusual and may indicate a heightened susceptibility to infection in cheetahs. Caution should be exercised in holding and translocating cheetahs where contact could be made with FeLV-infected domestic, feral, or wild felids.  相似文献   

10.
11.
The conversion of natural ecosystems due to anthropogenic activities has led to the destruction of natural habitats and to the deterioration of habitat quality. Top predators particularly respond sensitively to changes in habitat structures, including the availability of prey. The cheetah Acinonyx jubatus prefers small‐medium‐sized, wild ungulate prey due to the cheetah''s morphological adaptations. However, the majority of the species’ population is found beyond protected areas, where habitat structures, species abundances, and community composition are highly influenced by human activities. Only few studies have analyzed the diet preference of cheetahs in relation to prey availability and abundance for rangelands beyond protected areas in Eastern Africa. The study aimed to determine cheetah prey preference in the rangelands of south‐eastern Kenya based on scat analyses. We compared dietary preference of cheetah with prey availability. For this purpose, we conducted standardized game counts. We analyzed 27 cheetah scat samples collected across the same study area where we also conducted game counts. We found that Grant''s gazelle Gazella granti contributed the highest portion of cheetah''s diet, although Thomson''s gazelle Gazella thomsonii was the most abundant medium‐sized ungulate prey in the study areas. We also recorded two primate species, yellow baboon Papio cynocephalus and vervet monkey Chlorocebus pygerythrus, as well as the rock hyrax Procavia capensis in the cheetah diet. These species have never been documented as cheetah prey before. Furthermore, our results document livestock as potential prey for cheetahs. These observations underline that cheetah use diverse prey in rangelands outside protected areas, and that the abundance of specific prey does not influence cheetah prey preference.  相似文献   

12.
As a charismatic carnivore that is vulnerable to extinction, many studies have been conducted on predation by the cheetah Acinonyx jubatus . Cheetah are generally considered to capture medium-sized prey; however, which species are actually preferred and why has yet to be addressed. We used data from 21 published and two unpublished studies from six countries throughout the distribution of the cheetah to determine which prey species were preferred and which were avoided using Jacobs' index. The mean Jacobs' index value for each prey species was used as the dependent variable in multiple regression, with prey abundance and prey body mass as predictive variables. Cheetah prefer to kill and actually kill the most available prey present at a site within a body mass range of 23–56 kg with a peak (mode) at 36 kg. Blesbok, impala, Thomson's and Grant's gazelles, and springbok are significantly preferred, whereas prey outside this range are generally avoided. The morphological adaptations of the cheetah appear to have evolved to capture medium-sized prey that can be subdued with minimal risk of injury. Coincidentally, these species can be consumed rapidly before kleptoparasites arrive. These results are discussed through the premise of optimality theory whereby decisions made by the predator maximize the net energetic benefits of foraging. Information is also presented that allows conservation managers to determine which prey species should be in adequate numbers at cheetah reintroduction sites to support a cheetah population. Conversely, these results will illustrate which potential prey species of local conservation concern should be monitored for impact from cheetahs as several species are likely to be preyed upon more frequently than others.  相似文献   

13.
《Geobios》2014,47(1-2):39-44
It is generally believed that the skull CCEC-161821 of Acinonyx pardinensis from Saint-Vallier, an Early Pleistocene French locality, is similar to that of the modern cheetah, in contrast to several other Late Pliocene and Early Pleistocene Old World felids with cheetah-like teeth, assigned either to Acinonyx Brookes, 1828, or to Sivapanthera Kretzoi, 1929. Morphological comparisons and morphometric analysis of the fossil and recent material show that the Acinonyx pardinensis from Saint-Vallier, although dentally similar to the modern cheetah, is not cheetah-like in its skull shape. All those Late Pliocene and Early Pleistocene forms can also be included in Acinonyx, implying that the characteristic skull shape of the modern form is probably a recent acquisition.  相似文献   

14.
This paper presents the growth rate of 21 clinically normal, mother-raised. captive cheetah cubs from birth through 45 days of age. The development of a growth curve for healthy, mother-raised cheetah cubs provides a diagnostic tool for individuals involved in cheetah propagation. Use of the curve may alert caretakers to problems early and thus help reduce the high neonatal mortality rate seen in captive-born cheetah cubs. The growth curve was constructed using 21 (11 males and 10 females) captiveborn cheetah cubs from six litters (offspring of three unrelated adult males and three unrelated adult females) born at the Columbus Zoo from September 1985 through December 1989. Each cub was weighed to the nearest gram the morning after birth and approximately the same time every consecutive morning for 45 days. The mean weight the morning after birth was 463 g (range 385–542 g). The average litter size was 3.5 (range 2–4, n = 6). The daily weight gain was 40–50 g/cub/day.  相似文献   

15.
There is now considerable evidence to suggest the cheetah (Acinonyx jubatus) has limited genetic diversity. However, the extent of this and its significance to the fitness of the cheetah population, both in the wild and captivity, is the subject of some debate. This reflects the difficulty associated with establishing a direct link between low variability at biologically significant loci and deleterious aspects of phenotype in this, and other, species. Attempts to study one such region, the feline leucocyte antigen (FLA), are hampered by a general reliance on cloning and sequencing which is expensive, labour-intensive, subject to PCR artefact and always likely to underestimate true variability. In this study we have applied reference strand-mediated conformational analysis (RSCA) to determine the FLA-DRB phenotypes of 25 cheetahs. This technique was rapid, repeatable and less prone to polymerase chain reaction (PCR)-induced sequence artefacts associated with cloning. Individual cheetahs were shown to have up to three FLA-DRB genes. A total of five alleles were identified (DRB*ha14-17 and DRB*gd01) distributed among four genotypes. Fifteen cheetahs were DRB*ha14/ha15/ha16/ha17, three were DRB*ha15/ha16/ha17, six were DRB*ha14/ha16/ha17 and one was DRB*ha14/ha15/ha16/ha17/gd01. Sequence analysis of DRB*gd01 suggested it was a recombinant of DRB*ha16 and DRB*ha17. Generation of new alleles is difficult to document, and the clear demonstration of such an event is unusual. This study confirms further the limited genetic variability of the cheetah at a biologically significant region. RSCA will facilitate large-scale studies that will be needed to correlate genetic diversity at such loci with population fitness in the cheetah and other species.  相似文献   

16.
Deserts are particularly vulnerable to human impacts and have already suffered a substantial loss of biodiversity. In harsh and variable desert environments, large herbivores typically occur at low densities, and their large carnivore predators occur at even lower densities. The continued survival of large carnivores is key to healthy functioning desert ecosystems, and the ability to gather reliable information on these rare low density species, including presence, abundance and density, is critical to their monitoring and management. Here we test camera trap methodologies as a monitoring tool for an extremely rare wide-ranging large felid, the critically endangered Saharan cheetah (Acinonyx jubatus hecki). Two camera trapping surveys were carried out over 2–3 months across a 2,551km2 grid in the Ti-n-hağğen region in the Ahaggar Cultural Park, south central Algeria. A total of 32 records of Saharan cheetah were obtained. We show the behaviour and ecology of the Saharan cheetah is severely constrained by the harsh desert environment, leading them to be more nocturnal, be more wide-ranging, and occur at lower densities relative to cheetah in savannah environments. Density estimates ranged from 0.21–0.55/1,000km2, some of the lowest large carnivore densities ever recorded in Africa, and average home range size over 2–3 months was estimated at 1,583km2. We use our results to predict that, in order to detect presence of cheetah with p>0.95 a survey effort of at least 1,000 camera trap days is required. Our study identifies the Ahaggar Cultural Park as a key area for the conservation of the Saharan cheetah. The Saharan cheetah meets the requirements for a charismatic flagship species that can be used to “market” the Saharan landscape at a sufficiently large scale to help reverse the historical neglect of threatened Saharan ecosystems.  相似文献   

17.
Compared with the normospermic domestic cat, sperm metabolic function is compromised in the teratospermic cat and cheetah, but the pathway(s) involved in this deficiency are unknown. Glycolysis is essential for sperm motility, yet it appears to function normally in spermatozoa of either species regardless of structural morphology. We conducted a comparative study to further understand the mechanisms of energy production in felid spermatozoa, with the hypothesis that oxidative phosphorylation is required for normal sperm function and is impaired in teratospermic ejaculates. Electroejaculates from both species were stained with MitoTracker to quantify mitochondrial membrane potential (MMP) or were incubated to assess changes in sperm function (motility, acrosomal integrity, and lactate production) after mitochondrial inhibition with myxothiazol. Sperm midpiece dimensions also were quantified. Sperm mitochondrial fluorescence (directly proportional to MMP) was ~95% lower in the cheetah compared with the normospermic and teratospermic cat, despite the cheetah having a 10% longer midpiece. In both species, MMP was increased 5-fold in spermatozoa with retained cytoplasm compared with structurally normal cells. Inhibition of oxidative phosphorylation impaired sperm function in both species, but a 100-fold higher inhibitor concentration was required in the cat compared with the cheetah. Collectively, findings revealed that oxidative phosphorylation was required for sperm function in the domestic cat and cheetah. This pathway of energy production appeared markedly less active in the cheetah, indicating a species-specific vulnerability to mitochondrial dysfunction. The unexpected, cross-species linkage between retained cytoplasmic droplets and elevated MMP may reflect increased concentrations of metabolic enzymes or substrates in these structures.  相似文献   

18.
Knowledge of the abundance of animal populations is essential for their management and conservation. Determining reliable measures of abundance is, however, difficult, especially with wide-ranging species such as cheetah Acinonyx jubatus . This study generated a correction factor to calculate true cheetah density from spoor survey data and subsequently tested its accuracy using the following season's data. Data were collected from October 2005 to December 2006 on a known population of wild, free-ranging cheetah in the Jwana Game Reserve, Botswana. The cheetahs in the area were captured, tagged and photographed. The reserve was divided into twelve 9 km transects covering all vegetation types and prey densities. The total sampling distance was 8226 km, with a spoor density of 2.32 individual cheetah spoor per 100 km2. To determine a precise and accurate spoor density, it was necessary to sample for a longer period during the dry season (April–September) than during the wet season (October–March). This difference may be due to cheetah behavioural changes with seasonal variations in habitat and prey. The true density was 5.23 cheetahs  per 100 km2 ranging from 3.33 to 7.78 at the low and high points of the population, respectively. A positive linear correlation between spoor and true density was observed. This relationship differed in the wet and dry season and required refinement with the following season's data. Correction factors may be viable, but require further testing taking the behavioural responses to seasonal, habitat and prey variations into consideration.  相似文献   

19.
Reintroductions of large carnivores into enclosed reserves that confine movements may fail due to intensive intra-guild interspecific conflict. To assess conflict potential, in winter 2006 we used direct observations aided by radio-tracking to focally monitor continuously one female cheetah with cub (Acinonyx jubatus), a female leopard (Panthera pardus), and a lion pride (Panthera leo) at Shamwari Private Game Reserve, South Africa. Home ranges of all individuals/social groups overlapped, whereas core areas had little overlap. The cheetah core area had no overlap with the lion core area, with lion avoidance also recorded for a radio-tracked single female cheetah and a male leopard. The female cheetah with cub selected thicket habitat which was avoided by lions, the latter preferring naturally revegetated areas that were also selected by the female leopard. Lions also selected low elevations, which were avoided by the smaller felids. Habitat preference differences occurred at study area and home range levels, suggesting a broad-scale feline avoidance strategy to minimize intra-guild conflict. In addition, the focally monitored cheetah and leopard were often stationary when the lions were active, especially during nocturnal lion hunts. These intra-guild mechanisms of reintroduced carnivore coexistence should be tested with longer-term studies across enclosed systems of different sizes, and hosting varying carnivore guilds.  相似文献   

20.
对上海野生动物园内的6头驯养猎豹采取人工刺激的方法让它们逐步恢复短距离急速奔跑,并将这6头猎豹的行为、生理生化指标和精液与园内圈养和半散养的6头猎豹加以比较,结果表明训练后猎豹正在逐步恢复捕食、交配等野外行为特性,而且训练后猎豹的血红蛋白含量等生理生化指标和精液质量与圈养和半散养的猎豹发生了较为显著的变化.本研究结果对于保护及展示猎豹这一特有物种起到一定的积极作用.  相似文献   

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