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1.
Feline immunodeficiency virus (FIV) infects numerous wild and domestic feline species and is closely related to human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV). Species-specific strains of FIV have been described for domestic cat (Felis catus), puma (Puma concolor), lion (Panthera leo), leopard (Panthera pardus), and Pallas' cat (Otocolobus manul). Here, we employ a three-antigen Western blot screening (domestic cat, puma, and lion FIV antigens) and PCR analysis to survey worldwide prevalence, distribution, and genomic differentiation of FIV based on 3,055 specimens from 35 Felidae and 3 Hyaenidae species. Although FIV infects a wide variety of host species, it is confirmed to be endemic in free-ranging populations of nine Felidae and one Hyaenidae species. These include the large African carnivores (lion, leopard, cheetah, and spotted hyena), where FIV is widely distributed in multiple populations; most of the South American felids (puma, jaguar, ocelot, margay, Geoffroy's cat, and tigrina), which maintain a lower FIV-positive level throughout their range; and two Asian species, the Pallas' cat, which has a species-specific strain of FIV, and the leopard cat, which has a domestic cat FIV strain in one population. Phylogenetic analysis of FIV proviral sequence demonstrates that most species for which FIV is endemic harbor monophyletic, genetically distinct species-specific FIV strains, suggesting that FIV transfer between cat species has occurred in the past but is quite infrequent today.  相似文献   

2.
Human population growth around protected areas increases the contact between wild and domestic animals, promoting disease transmission between them. This study investigates the exposure of free-ranging wild carnivores and domestic dogs to canine distemper virus (CDV) and parvovirus in Emas National Park (ENP) in the Cerrado savanna of central Brazil. Serum samples were collected from 169 wild carnivores, including the maned wolf (Chrysocyon brachyurus), crab-eating fox (Cerdocyon thous), hoary fox (Pseudalopex vetulus), puma (Puma concolor), ocelot (Leopardus pardalis), pampas cat (Leopardus colocolo), jaguarundi (Herpailurus yagouaroundi), striped hog-nosed skunk (Conepatus semistriatus) and coati (Nasua nasua), and from 35 domestic dogs living on rural properties bordering ENP. Serological tests showed that 10.6% of wild carnivores (maned wolves, crab-eating foxes and ocelots) and 71.4% of domestic dogs were exposed to CDV, and 56.8% of wild carnivores, including all species sampled except coatis, and 57.1% of domestic dogs were exposed to parvovirus. This report is the first to indicate that the free-ranging pampas cat, jaguarundi and striped hog-nosed skunk are exposed to parvovirus. CDV and parvovirus deserve attention in ENP, and it is extremely important to monitor the health of carnivore populations and perform molecular diagnosis of the viruses to determine the possible involvement of the domestic dog in their transmission.  相似文献   

3.
Wild felids and canids are usually the main predators in the food chains where they dwell and are almost invisible to behavior and ecology researchers. Due to their grooming behavior, they tend to swallow shed hair, which shows up in the feces. DNA found in hair shafts can be used in molecular studies that can unravel, for instance, genetic variability, reproductive mode and family structure, and in some species, it is even possible to estimate migration and dispersion rates in given populations. First, however, DNA must be extracted from hair. We extracted successfully and dependably hair shaft DNA from eight wild Brazilian felids, ocelot, margay, oncilla, Geoffroy's cat, pampas cat, jaguarundi, puma, and jaguar, as well as the domestic cat and from three wild Brazilian canids, maned wolf, crab-eating fox, and hoary fox, as well as the domestic dog. Hair samples came mostly from feces collected at the S?o Paulo Zoo and were also gathered from non-sedated pet or from recently dead wild animals and were also collected from museum specimens. Fractions of hair samples were stained before DNA extraction, while most samples were not. Our extraction protocol is based on a feather DNA extraction technique, based in the phenol:chloroform:isoamyl alcohol general method, with proteinase K as digestive enzyme.  相似文献   

4.
Erythrocytic polycythemia in rats was produced by chronic injections of cobalt chloride. At the peak of polycythemia, i.e. after eleven weeks of cobalt injections, the P50 decreased from the original, normal values 36.3 torr to 33.0 torr. Four weeks after the cessation of cobalt injection the hemoglobin concentration remained still relatively high and an additional decrease of P50 to 31.0 torr was observed. Further development was characterized by a gradual return of both P50 and hemoglabin levle toward the normal values.  相似文献   

5.
Neuroglobin (Ngb) is a hexacoordinate globin expressed in the nervous system of vertebrates, involved in neuroprotection. O2 equilibrium measurements on mouse Ngb yielded significantly different P50 values, ranging from ∼2 torr to ∼10 torr. By a kinetic approach minimizing the effects of protein autoxidation, we measured P50 = 2.2 torr at 20 °C. As predicted from the structure, O2 binds to the Y44D Ngb mutant more quickly (k = 2.2 s−1 vs 0.15 s−1) and with slightly higher affinity (P50 = 1.3 torr) than wild-type. In addition, we introduced a novel reduction protocol for metNgb based on NADH:flavorubredoxin oxidoreductase (FlRd-red) from Escherichia coli, a candidate for the Ngb reducing activity recently identified in E. coli extracts. Interestingly, E. coli FlRd-red shares sequence similarity with the FAD-binding domain of the human apoptosis-inducing factor, a finding which may have unexpected significance with reference to the mechanism of neuroprotection by Ngb.  相似文献   

6.
Feline immunodeficiency virus (FIV) is a lentivirus which causes an AIDS-like disease in domestic cats (Felis catus). A number of other felid species, including the puma (Puma concolor), carry a virus closely related to domestic cat FIV. Serological testing revealed the presence of antibodies to FIV in 22% of 434 samples from throughout the geographic range of the puma. FIV-Pco pol gene sequences isolated from pumas revealed extensive sequence diversity, greater than has been documented in the domestic cat. The puma sequences formed two highly divergent groups, analogous to the clades which have been defined for domestic cat and lion (Panthera leo) FIV. The puma clade A was made up of samples from Florida and California, whereas clade B consisted of samples from other parts of North America, Central America, and Brazil. The difference between these two groups was as great as that reported among three lion FIV clades. Within puma clades, sequence variation is large, comparable to between-clade differences seen for domestic cat clades, allowing recognition of 15 phylogenetic lineages (subclades) among puma FIV-Pco. Large sequence divergence among isolates, nearly complete species monophyly, and widespread geographic distribution suggest that FIV-Pco has evolved within the puma species for a long period. The sequence data provided evidence for vertical transmission of FIV-Pco from mothers to their kittens, for coinfection of individuals by two different viral strains, and for cross-species transmission of FIV from a domestic cat to a puma. These factors may all be important for understanding the epidemiology and natural history of FIV in the puma.  相似文献   

7.
8.
The natural occurrence of lentiviruses closely related to feline immunodeficiency virus (FIV) in nondomestic felid species is shown here to be worldwide. Cross-reactive antibodies to FIV were common in several free-ranging populations of large cats, including East African lions and cheetahs of the Serengeti ecosystem and in puma (also called cougar or mountain lion) populations throughout North America. Infectious puma lentivirus (PLV) was isolated from several Florida panthers, a severely endangered relict puma subspecies inhabiting the Big Cypress Swamp and Everglades ecosystems in southern Florida. Phylogenetic analysis of PLV genomic sequences from disparate geographic isolates revealed appreciable divergence from domestic cat FIV sequences as well as between PLV sequences found in different North American locales. The level of sequence divergence between PLV and FIV was greater than the level of divergence between human and certain simian immunodeficiency viruses, suggesting that the transmission of FIV between feline species is infrequent and parallels in time the emergence of HIV from simian ancestors.  相似文献   

9.
The effects of autologous erythrocyte infusion on improving exercise performance at high altitude have not previously been studied. The effects of erythrocyte infusion on 3.2-km (2-mile) run performance were evaluated during 3 days (HA3) and 14 days (HA14) exposure to high altitude (4300 m) in erythrocyte-infused (ER) and control (CON) subjects that were initially matched (P>0.05; n = 8 in each group) for age, body size and aerobic fitness. After sea-level runs (SL; 50 m), unacclimated-male subjects received either 700 ml of saline and autologous erythrocytes (42% hematocrit; ER) or saline alone (CON). The 3.2-km run times (min:s) did not differ (P>0.05) between groups at SL [mean (SEM) ER, 13:14 (00:19); CON, 13:39 (00:32)] or during HA3 [ER, 19:02 (00:18); CON, 19:44 (00:43)] and HA14 [ER, 17:44 (00:27); CON, 18:45 (00:55)] but times were slower (P<0.05) when comparing HA3 or HA14 to SL. Heart rates (HR) did not differ between groups at SL [ER, 188 (3) beats x min(-1); CON, 191 (3) beats x min(-1)], or during HA3 [ER, 170 (4) beats x min(-1); CON, 178 (4) beats x min(-1)] and HA14 [ER, 162 (6) beats x min(-1); CON, 169 (5) beats x min(-1)], but HR were lower (P<0.05) when comparing HA3 or HA14 to SL. Ratings of perceived exertion (local, central, and overall ratings) did not differ between groups at SL, HA3 or HA14, but local ratings were higher (P<0.05) at HA3 and HA14 compared to SL, and overall ratings were higher for HA3 than SL. Analysis of covariance (adjusted for SL group run times) revealed (min:s) 00:14 (HA3) and 00:28 (HA14) mean improvement tendencies (P>0.05) for ER compared to CON. Thus, no significant improvements in 3.2-km run performance were associated with erythrocyte infusion, although the ER group showed a tendency to run slightly faster at high altitude.  相似文献   

10.
California is home to both the native state-threatened Sierra Nevada red fox (Vulpes vulpes necator), which historically inhabited high elevations of the Sierra Nevada and Cascade mountains, and to multiple low-elevation red fox populations thought to be of exotic origin. During the past few decades the lowland populations have dramatically expanded their distribution, and possibly moved into the historic range of the native high-elevation fox. To determine whether the native red fox persists in its historic range in California, we compared mitochondrial cytochrome-b haplotypes of the only currently-known high-elevation population (n = 9 individuals) to samples from 3 modern lowland populations (n = 35) and historic (1911–1941) high-elevation (n = 22) and lowland (n = 7) populations. We found no significant population differentiation among the modern and historic high-elevation populations (average pairwise F ST = 0.06), but these populations differed substantially from all modern and historic lowland populations (average pairwise F ST = 0.52). Among lowland populations, the historic and modern Sacramento Valley populations were not significantly differentiated from one another (F ST = −0.06), but differed significantly from recently founded populations in the San Francisco Bay region and in southern California (average pairwise F ST = 0.42). Analysis of molecular variance indicated that 3 population groupings (mountain, Sacramento Valley, and other lowland regions) explained 45% of molecular variance (F CT = 0.45) whereas only 4.5% of the variance was partitioned among populations within these groupings (F SC = 0.08). These findings provide strong evidence that the native Sierra Nevada red fox has persisted in northern California. However, all nine samples from this population had the same haplotype, suggesting that several historic haplotypes may have become lost. Unidentified barriers have apparently prevented gene flow from the Sacramento Valley population to other eastern or southern populations in California. Future studies involving nuclear markers are needed to assess the origin of the Sierra Nevada red fox and to quantify levels of nuclear gene flow.  相似文献   

11.
Women at altitude: carbohydrate utilization during exercise at 4,300 m.   总被引:4,自引:0,他引:4  
To evaluate the hypothesis that exposure to high altitude would reduce blood glucose and total carbohydrate utilization relative to sea level (SL), 16 young women were studied over four 12-day periods: at 50% of peak O(2) consumption in different menstrual cycle phases (SL-50), at 65% of peak O(2) consumption at SL (SL-65), and at 4,300 m (HA). After 10 days in each condition, blood glucose rate of disappearance (R(d)) and respiratory exchange ratio were measured at rest and during 45 min of exercise. Glucose R(d) during exercise at HA (4.71 +/- 0.30 mg. kg(-1). min(-1)) was not different from SL exercise at the same absolute intensity (SL-50 = 5.03 mg. kg(-1). min(-1)) but was lower at the same relative intensity (SL-65 = 6.22 mg. kg(-1). min(-1), P < 0.01). There were no differences, however, when glucose R(d) was corrected for energy expended (kcal/min) during exercise. Respiratory exchange ratios followed the same pattern, except carbohydrate oxidation remained lower (-23.2%, P < 0.01) at HA than at SL when corrected for energy expended. In women, unlike in men, carbohydrate utilization decreased at HA. Relative abundance of estrogen and progesterone in women may partially explain the sex differences in fuel utilization at HA, but subtle differences between menstrual cycle phases at SL had no physiologically relevant effects.  相似文献   

12.
The potential for rescuing immature oocytes from the ovaries of females of rare felid species which die or undergo medical ovariohysterectomy was evaluated. Ovaries were recovered from 13 species representing 35 individuals in good-to-poor health. Although the majority of females were 10 yr of age or older and in fair-to-poor health, a total of 846 oocytes were recovered of which 608 (71.9%) were classified as fair-to-excellent quality. One hundred of these oocytes were used for initial maturation classification and as parthogenetic controls. Overall, of the 508 fair-to-excellent quality oocytes placed in culture, 164 (32.3%) matured to metaphase II in vitro. For species in which 3 or more individuals yielded oocytes, mean oocyte maturation rates were as follows: 36.2%, tiger; 27.9% leopard; and 8.3%, cheetah. In vitro insemination of oocytes resulted in fertilization (2 polar bodies, 2 pronuclei, or cleavage) rates of 9.1% to 28.6% (leopard) using homologous fresh spermatozoa and 4.0% (lion) to 40.0% (puma) using homologous frozen-thawed spermatozoa. Inseminations using heterologous (domestic cat) spermatozoa also resulted in fertilized oocytes in the tiger, leopard, snow leopard, puma, serval, and Geoffroy's cat (range in fertilization rate, 5.0% for leopard to 46.2% for puma). Cleaved embryos resulted from the insemination of leopard oocytes with homologous sperm (n = 1 embryo) and puma oocytes with domestic cat sperm (n = 3 embryos). These results demonstrate that immature ovarian oocytes from rare felid species can be stimulated to mature in vitro despite an excision-to-culture interval as long as 36 h.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

13.
Capillarity and fiber composition were studied by the ATPase technique in frozen samples of sternothyroid muscle of dogs from sea level (SL) and high altitude (3,300–4,300 m) (HA). Capillary density (CD), capillary to fiber ratio (C:F) and fiber cross sectional area (FCSA) were measured. The mean CD was 791/mm2 at SL and 743/mm2 at HA. CD was linearly related to FCSA in the SL animals (CD=1112.8–0.10 FCSA; r=–0.63). In both SL and HA animals, C:F was linearly and positively correlated with FCSA. There was no significant difference between the two regression lines; therefore, only one line represents all the data (C:F=0.78+(5.19×10–4) FCSA; r=0.77). Thus, at a given FCSA the C:F was the same for SL and HA dogs. Two types of fibers were identified: type I (slow twitch) (42%) and type II (fast twitch) (58%). No differences in fiber composition or FCSA were observed between the SL and HA dogs. These results indicate that moderate levels of hypoxia do not affect the capillarity of dog skeletal muscle.  相似文献   

14.
High-altitude (HA) natives have blunted ventilatory responses to hypoxia (HVR), but studies differ as to whether this blunting is lost when HA natives migrate to live at sea level (SL), possibly because HVR has been assessed with different durations of hypoxic exposure (acute vs. sustained). To investigate this, 50 HA natives (>3,500 m, for >20 yr) now resident at SL were compared with 50 SL natives as controls. Isocapnic HVR was assessed by using two protocols: protocol 1, progressive stepwise induction of hypoxia over 5-6 min; and protocol 2, sustained (20-min) hypoxia (end-tidal Po(2) = 50 Torr). Acute HVR was assessed from both protocols, and sustained HVR from protocol 2. For HA natives, acute HVR was 79% [95% confidence interval (CI): 52-106%, P = not significant] of SL controls for protocol 1 and 74% (95% CI: 52-96%, P < 0.05) for protocol 2. By contrast, sustained HVR after 20-min hypoxia was only 30% (95% CI: -7-67%, P < 0.001) of SL control values. The persistent blunting of HVR of HA natives resident at SL is substantially less to acute than to sustained hypoxia, when hypoxic ventilatory depression can develop.  相似文献   

15.
Abstract A number of studies on mammalian species that have adapted to urban areas suggest survival may be higher for urban populations than rural populations. We examined differences in fatalities between an urban and rural population of fox squirrels (Sciurus niger). We radiocollared (n = 50 rural, n = 78 urban) fox squirrels during approximately 2 years. We found monthly survival of rural fox squirrels (Ŝ = 0.936) was lower than urban fox squirrels (Ŝ = 0.976) over the same 12-month period. Nonetheless, when comparing a 24-month period of survival data on urban squirrels with an 18-month period on the rural squirrels (periods overlapped for 12 months), survival rates were more similar between urban (Ŝ = 0.938) and rural squirrels (Ŝ = 0.945). Our data suggest that sex and season may influence survival of urban squirrels and not rural squirrels. We also found that cause of fatalities differed between the urban and rural squirrels, with >60% of fatalities on the rural site caused by predation. In contrast, <5% of the fatalities on the urban site were caused by predation and >60% of urban fox squirrel fatalities were caused by motor vehicle collisions. This study illustrates the need to advance our ability to understand, predict, and mitigate effects of urbanization on wildlife resources.  相似文献   

16.
ABSTRACT Information on factors affecting population size of pumas (Puma concolor) can be important because their principal prey over most of the western United States are valued big game species (e.g., mule deer [Odocoileus hemionus], elk [Cervus elaphus], and bighorn sheep [Ovis canadensis]). Based on the hypothesis that puma numbers are limited by their food supply, puma populations should track changes in prey abundance by growing exponentially with increases in prey and by declining with a lag response when prey decreases. Additional predictions proposed by researchers are that body mass of pumas, female productivity, kitten survival, and adult survival should decrease after a prey decline. We used a 15-year database from a hunted population of pumas in southern Idaho and northwestern Utah to test these predictions. During the 15-year time span of the database, a major decline in mule deer abundance occurred. Estimates of puma numbers and demographic characteristics came from intensive capture and radiocollaring efforts. We calculated kitten and adult survival with MICROMORT software. We found that adult puma numbers increased exponentially at r = 0.07 during a period of increasing mule deer numbers. Four years after the mule deer abundance declined, puma numbers decreased at a rate of r = −0.06. Body mass of female pumas was lower after the decline in puma numbers (42.6 ± SE = 1.2 kg, n = 40 vs. 40.1 ± 0.64 kg, n = 34, t = 5.06, P = 0.045). Kitten survival was less after the decline in deer abundance (0.573 ± 0.016, n = 30 vs. 0.856 ± 0.015, n = 25, Z = 2.40, P < 0.01). Survival of resident females was significantly less after the decline in puma numbers (0.783 ± 0.03 vs. 0.929 ± 0.019, U = 55.0, P = 0.009). Female productivity did not differ before or after the decline in deer abundance. Our results supported the majority of the predictions concerning the impact of changing deer abundance, which supported the hypothesis that the abundance of mule deer limited our population of pumas.  相似文献   

17.
Scent marking is critical to intraspecific communication in many mammal species, but little is known regarding its role in communication among different species. We used 4 years of motion-triggered video to document the use of scent marking areas—termed “community scrapes”—by pumas (Puma concolor) (http://www.momo-p.com/showdetail-e.php?movieid=momo160812pc01a) and other carnivore species. We found that gray foxes (Urocyon cinereoargenteus) routinely rubbed their cheeks on puma scrapes (http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc01a), and tested a series of hypotheses to determine its function. We found that gray foxes selected puma scrapes over other objects, and cheek rubbing by foxes was also correlated with how recently a puma had visited the scrape, suggesting that foxes were intent upon accumulating fresh puma scent. Cheek rubbing by foxes was not correlated with their breeding season or with how recently another fox had visited the site. Finally we found a cascading pattern in the occurrence of pumas, coyotes (Canis latrans) and gray foxes at community scrapes, suggesting that gray foxes may use puma scent to deter predation. This is the first published study to find evidence of a subordinate species using the scent of a dominant species to communicate with heterospecifics. The behavioral cascade we found in scent marking patterns also suggests that scent marking could be a mechanism that impacts the distribution and abundance of species. Additional videos pertaining to this article include http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc02a, and http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc03a.  相似文献   

18.
ABSTRACT

This study describes the reproductive cycle of the common limpet (Patella vulgata) and rough limpet (Patella ulyssiponensis) from the Algarve coast (southern Portugal). Individuals of both species were sampled monthly during two consecutive years, and subjected to gonad histology and calculation of the mean gonadal index (GI). Both species had balanced sex ratios (P. vulgata = 1M: 0.98F; P. ulyssiponensis = 1M: 1.03F), similar size-frequency distribution between sexes, and equivalent mean shell lengths (SL) and total weights (TW) between males and females. In these protandrous hermaphrodites, the estimated size at sex change was slightly smaller in P. vulgata (SL50 ≈ 29 mm) than in P. ulyssiponensis (SL50 ≈ 36 mm). The reproductive cycles of both species were characterised by a main spawning season in early spring to early summer, sometimes including subsidiary spawning events. A comparison of the main spawning season throughout the species distributional ranges revealed that populations of P. vulgata and P. ulyssiponensis from southern Portugal have later spawning periods than other populations from the northeastern Atlantic Ocean. The present information is relevant for conservation purposes and for the proposal of management measures for the harvesting activity targeting P. vulgata and P. ulyssiponensis in southern Portugal.  相似文献   

19.
Synopsis Routine respiratory metabolic rates of mosquitofish (0.2 g live weight) were determined at 10, 15, 20, 25, 30, and 35°C at normoxic, hypoxic (= 40 torr PO2), and extreme hypoxic (= 25 torr PO2) conditions. Rates generally increased with increases in temperature (overall Q10 = 2.11 at normoxia). Significant depressions (P<0.05) in rates were measured at 30 and 35°C at extreme hypoxic conditions. Males exhibited higher mortality at extreme hypoxia than females, especially at 35°C. Metabolic rates were significantly elevated at hyperoxic conditions (= 300 torr PO2) at 25 and 30°C, but not at 35°C. Resting routine rates of less-confined fish were determined at 20, 25, and 30°C at normoxia and were significantly lower than the routine rates at the same temperatures. Behavioral experiments showed that aquatic surface respiration is initiated by mosquitofish at 20–65 torr PO2 and is obligatory below 20 torr at 20° C. Overall, respiratory metabolic rates provide a quantitative metabolic basis from which predation rates of mosquitofish in various environments can be estimated.  相似文献   

20.
Wildlife managers require reliable information on factors that influence animal populations to develop successful management programs, including the puma (Puma concolor), in western North America. As puma populations have recovered in recent decades because of restrictions on human-caused mortality, managers need a clear understanding of the factors that limit or regulate puma populations and how those factors might be manipulated to achieve management objectives, including sustaining puma and other wildlife populations, providing hunting opportunity, and reducing puma interactions with people. I synthesized technical literature on puma populations, behavior, and relationships with prey that have contributed to hypotheses on puma population limitation and regulation. Current hypotheses on puma population limitation include the social limitation hypothesis and the food limitation hypothesis. Associated with each of those are 2 hypotheses on puma population regulation: the social regulation hypothesis and the competition regulation hypothesis. I organize the biological and ecological attributes of pumas reported in the literature under these hypotheses. I discuss the validity of these hypotheses based on the limits of the research associated with the hypotheses and the evolutionary processes theoretically underlying them. I review the management predictions as framed by these hypotheses as they pertain to puma hunting, puma-prey relationships, and human-puma interactions. The food limitation and competition regulation hypotheses explain more phenomena associated with puma and likely would guide more successful management outcomes. © 2019 The Wildlife Society.  相似文献   

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