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1.
We examine the effect of body mass on milk composition among Old World fruit bats, including Pteropus pumilus (0.175 kg), Pteropus rodricensus (0.265 kg), Pteropus hypomelanus (0.571 kg), and Pteropus vampyrus (1.133 kg). We describe intra- and interspecific differences in the proximate composition of milk among these four species and the minerals and fatty acids in the milk of the latter two species. There were no differences between species in the concentrations of dry matter, fat, or lactose in milk. However, there were significant, although small, differences in the protein content of milk among species, with protein being significantly greater in P. rodricensus than in P. pumilus and P. hypomelanus and protein being significantly less in P. hypomelanus than in P. rodricensus and P. vampyrus. There were no differences in mineral content between P. hypomelanus and P. vampyrus in milk minerals, but minor differences were evident in fatty acids 12:0, 14:0, 18:0, 18:1n11, and 18:2n6. Our findings suggest that milk composition is relatively constant across lactation for most proximate, mineral, and fatty acid components. We found a significant increase in dry matter and energy across lactation in the concentration of dry matter and energy in P. pumilus and fat in P. hypomelanus. In P. hypomelanus, we found a significant increase in the concentration of fatty acids 10:0 and 20:1n9 and a significant decrease in Iso15 and 20:1n7. No other differences associated with day of lactation were found. These findings suggest that milk composition is generally similar within the genus Pteropus, despite a 6.5-fold difference in body mass between species that we evaluated.  相似文献   

2.
Three species of flying fox (Pteropus hypomelanus, P. vampyrus, and P. lylei) from Malaysia and Vietnam were screened for apicomplexan parasites by thin blood smears and polymerase chain reaction. Only 1 of 16 bats sampled from 3 localities in southeast Asia was found to be infected (P. hypomelanus from Pulau Pangkor, Malaysia). We observed micro- and macrogametocytes, with morphology consistent with Hepatocystis sp. parasites, using light microscopy. Phylogenetic analysis of the cytochrome b gene showed that the parasite from P. hypomelanus groups with 2 published sequences from Hepatocystis spp., including one from Cynopterus brachyotis, another fruit bat in the Pteropodidae.  相似文献   

3.
This study reports observations on the collection and characteristics of semen from free-range populations of flying fox in Brisbane, Australia. Semen was successfully recovered by electroejaculation from 107 of 115 wild flying foxes (Pteropus alecto, Pteropus poliocephalus and Pteropus scapulatus). A proportion of ejaculates collected from all three species contained seminal vesicle secretions, the incidence of which appeared related to breeding season. Ejaculate volume was small (5--160 microL), requiring a specialised collection vessel and immediate extension to avoid desiccation. Sperm morphological abnormalities and characteristics are described for the first time. In two species (P. scapulatus and P. alecto), sperm quality varied with breeding season. Dilution in Tris-citrate-fructose buffer and subsequent incubation (37 degrees C) of Pteropus semen for 2-3h appeared to have a negative impact on sperm motility and the percentage of sperm with intact plasma membranes and acrosomes and represents a concern for the potential development and use of assisted breeding technology in these species. Preliminary attempts to develop a short-term chilled preservation protocol for flying fox semen revealed that sperm viability (percentage motility and percentage live sperm with intact acrosomes) was significantly reduced after 102 h chilled storage at 5 degrees C; nevertheless, approximately 40% of the spermatozoa were still motile and contained intact acrosomes. Glycerol was neither protective nor detrimental to sperm survival during chilled storage. Microbial flora of the prepuce, urethra and semen of all species were isolated and their antibiotic susceptibility tested. Tetracycline, penicillin, ciprofloxacin, and ceftazidime were the most effective antibiotics in preventing growth of all identified bacteria; however, their effects on sperm survival were not investigated.  相似文献   

4.
This study examined behavioral and physiological responses (changes in inter-animal spacing, total glucocorticoids, testosterone, and body mass) to the formation of breeding and same-sex groups in two bat species, the socially gregarious Malayan Flying Fox (Pteropus vampyrus) and the less social Little Golden-mantled Flying Fox (Pteropus pumilus). We hypothesized that social instability, especially in the breeding groups and especially in P. vampyrus, would result in elevated glucocorticoids and that social facilitation of breeding and/or male-male competition would result in persistently higher levels of testosterone in breeding males. Seasonal rhythms in all measures were also predicted, and the glucocorticoid stress response was expected to vary by sex, season, and group type. Nearly all animals responded to group formation with elevated glucocorticoids, but, for breeding animals (especially aggressive male P. vampyrus), these responses persisted over time. In both species, breeding group formation resulted in elevated testosterone in males. Glucocorticoids, testosterone, testes volume, and body mass generally peaked in the breeding season in males (late summer and early autumn), but the seasonal glucocorticoid peak in females occurred in late winter and early spring. All animals responded to restraint stress with elevations in glucocorticoids that largely did not differ by sex, time of year, reproductive condition, group type, or, in lactating females, the presence of her pup. Changes in both behavior and physiology were more evident in P. vampyrus than in P. pumilus, and we believe that their underlying social differences influenced their responses to group formation and to the changing seasonal environment.  相似文献   

5.
栖息地丧失和捕猎导致许多大型狐蝠濒危。尽管在东半球热带地区已经禁止捕猎和采伐,狐蝠的数量仍然在下降。既能维护当地居民利益又能保护狐蝠的折衷对策是生态旅游。然而,人类活动对狐蝠的影响还是未知的。菲律宾Boracay和Mambukal都是旅游区,前者游人少而稳定,后者游人密集且变异较大。我们用非损伤取样法研究了这两个旅游区三种狐蝠的生理紧张情况。在Mambukal,当狐蝠外出采食时,采集狐蝠的粪样,实验室分析粪样肾上腺皮质激素代谢物(GCM)浓度。我们观察记录了紧张反应等一些行为,同时记录了环境因素和人类活动情况。结果表明狐蝠已经习惯了游人的活动,表现在:(1)我们发现两个旅游区游人数量和活动强度差异显著,但是两地狐蝠的行为没有明显的差异;并且在有干扰和无干扰的日期之间,狐蝠的行为也无显著差异;两个旅游区的狐蝠行为表达一致;(2)各种行为与测定的粪样GCM浓度都不相关;(3)尽管在不同研究地点人类活动变异很大,我们发现人类活动并未影响粪样GCM浓度;不过,栖息在狐蝠群中心位置个体的粪样GCM浓度低于在群外围个体的GCM浓度;(4)一些环境因素(如干扰以及与栖息群的距离)影响狐蝠一些行为(如不安、身体护理和哈欠)的表达。如果干扰没有造成狐蝠紧张反应,那么生态旅游将不失为一种保护濒危狐蝠栖息地的理想方案。不过,我们还应认识到,人类干扰对狐蝠行为的影响可能比本研究观察到的更加复杂。因此,对于保护濒危狐蝠,时刻保持干扰最小是最好的选择。  相似文献   

6.
Recent serologic studies have identified flying foxes (Pteropus spp.) as carriers of leptospirosis; however, little is known about the role of flying foxes as carriers of pathogenic Leptospira spp. To determine if Australian Pteropus spp. are carriers of pathogenic Leptospira spp., TaqMan real-time polymerase chain reaction (PCR) was used to detect leptospiral DNA in kidney and urine specimens from four species of flying fox, including the spectacled flying fox (Pteropus conspicillatus), black flying fox (Pteropus alecto), grey-headed flying fox (Pteropus poliocephalus), and little red flying fox (Pteropus scapulatus). Of the 173 kidney samples tested, 19 (11%) were positive for leptospiral DNA. Positive individuals were detected in all four species; significant differences in prevalence were not detected between species, between species within the same geographic area, or between geographically separated samples from the same species. Of the 46 urine samples tested, 18 (39%) tested positive by PCR, confirming that flying foxes shed leptospires into the environment. The detection of leptospiral DNA in the kidneys and urine of flying foxes suggests that flying foxes are carriers of pathogenic Leptospira spp. No evidence collected in the present study, however, suggests that flying foxes pose a significant risk of leptospirosis to the wider community or that humans who are in regular, close contact with flying foxes are at risk for leptospirosis.  相似文献   

7.
Although much is known about the behaviour of the Indian Flying fox (Pteropus giganteus Brunnich) whilst at the roost (e.g. Neuweiler, 1969), very little is known of its foraging behaviour. The purpose of this paper is to describe the techniques and results of a preliminary radio-tracking study of P. giganteus. In view of the fact that some species of Pteropus are commercial pests (Ratcliffe, 1932) and others are declining rapidly in numbers so as to cause alarm to conservation bodies (Nicoll & Racey, 1981), it is likely that this genus will receive considerable attention in the future. P. giganteus is the largest species of frugivorous bat in Ceylon and is most widely distributed throughout the wet zone (Eisenberg & McKay, 1970).  相似文献   

8.
The spectacled flying fox, Pteropus conspicillatus, is listed as vulnerable in Australia and is under threat from numerous impacts. Primers to amplify eight co-dominant microsatellite loci were designed for Pteropus conspicillatus, based on an enriched genomic library. Four loci were monomorphic in this species while the remaining four loci were highly polymorphic with 16–23 alleles. Two of the four monomorphic loci were found to be polymorphic in Pteropus alecto, a closely related congener. All but one of the six polymorphic loci were in Hardy Weinberg equilibrium. Additionally, six microsatellite loci isolated for Pteropus rodricensis were tested against individuals of P. conspicillatus with all loci amplifying reliably. These loci will be used to investigate population genetic structure in the vulnerable spectacled flying fox.  相似文献   

9.
Hendra virus (HeV) is a lethal paramyxovirus which emerged in humans in 1994. Poor understanding of HeV dynamics in Pteropus spp. (flying fox or fruit bat) reservoir hosts has limited our ability to determine factors driving its emergence. We initiated a longitudinal field study of HeV in little red flying foxes (LRFF; Pteropus scapulatus) and examined individual and population risk factors for infection, to determine probable modes of intraspecific transmission. We also investigated whether seasonal changes in host behaviour, physiology and demography affect host-pathogen dynamics. Data showed that pregnant and lactating females had significantly higher risk of infection, which may explain previously observed temporal associations between HeV outbreaks and flying fox birthing periods. Age-specific seroprevalence curves generated from field data imply that HeV is transmitted horizontally via faeces, urine or saliva. Rapidly declining seroprevalence between two field seasons suggests that immunity wanes faster in LRFF than in other flying fox species, and highlights the potentially critical role of this species in interspecific viral persistence. The highest seroprevalence was observed when animals showed evidence of nutritional stress, suggesting that environmental processes that alter flying fox food sources, such as habitat loss and climate change, may increase HeV infection and transmission. These insights into the ecology of HeV in flying fox populations suggest causal links between anthropogenic environmental change and HeV emergence.  相似文献   

10.
R Mathur  R B Gupta  A Mathur 《Acta anatomica》1979,103(3):313-318
Histochemical study of the innervation of the heart of the Indian flying fox Pteropus giganteus has been made using Coupland and Holmes' technique for cholinesterase. Distribution of nerve plexuses in the heart wall has been described. Nerve cells, nerve endings and various types of synapses have been reported. Specialized muscle fibres are found to contain less nerve fibres and conduction of the impulse of contraction is reported to take place through muscle fibres.  相似文献   

11.
Although chemoreception plays an important role in social organization of many lizards, only a few studies have examined the chemicals found in secretions used for intraspecific communication. We report the composition of the secretion of the femoral glands of males of the spiny-footed lizard (Acanthodactylus erythrurus). On the basis of mass spectra, obtained by GC/MS, we identified 45 lipophilic compounds, including several alcohols ranging from 10 to 29 carbon atoms (mainly hexacosanol and tetracosanol), steroids (mainly cholesterol and dehydrocholesterol), n-C9 to n-C20 carboxylic acids, esters of carboxylic acids, and minor components such as lactones, ketones, squalene and a-tocopherol. Some of these compounds are reported for the first time in lizards. Adult and subadult males differed in the composition of secretions, with C9 to C15 carboxylic acids being more abundant in younger than in older lizards, whereas C16 to C20 carboxylic acids were more abundant in older lizards. Also, older lizards had significant lower proportions of cholesterol and campesterol but higher proportions of dehydrocholesterol.  相似文献   

12.
Isolation of Nipah virus from Malaysian Island flying-foxes   总被引:17,自引:0,他引:17  
In late 1998, Nipah virus emerged in peninsular Malaysia and caused fatal disease in domestic pigs and humans and substantial economic loss to the local pig industry. Surveillance of wildlife species during the outbreak showed neutralizing antibodies to Nipah virus mainly in Island flying-foxes (Pteropus hypomelanus) and Malayan flying-foxes (Pteropus vampyrus) but no virus reactive with anti-Nipah virus antibodies was isolated. We adopted a novel approach of collecting urine from these Island flying-foxes and swabs of their partially eaten fruits. Three viral isolates (two from urine and one from a partially eaten fruit swab) that caused Nipah virus-like syncytial cytopathic effect in Vero cells and stained strongly with Nipah- and Hendra-specific antibodies were isolated. Molecular sequencing and analysis of the 11,200-nucleotide fragment representing the beginning of the nucleocapsid gene to the end of the glycoprotein gene of one isolate confirmed the isolate to be Nipah virus with a sequence deviation of five to six nucleotides from Nipah virus isolated from humans. The isolation of Nipah virus from the Island flying-fox corroborates the serological evidence that it is one of the natural hosts of the virus.  相似文献   

13.
Structure and innervation of the trachea of the large flying fox (Pteropus vampyrus) were examined by mean hematoxylin-eosin staining and immunohistochemical methods. The tracheal rings were predominantly comprised of bone with a small amount of hyaline cartilage. Bone contained bone marrow and hyaline cartilage attached at the ends of the tracheal rings. The tracheal rings in the anterior third of the trachea were connected at each end with connective tissue to almost form a ring. A narrow membranous wall comprising a single layer of smooth muscle was present in the middle third, while inner and outer layers of smooth muscle were present in the posterior third. Protein gene product 9.5 (PGP 9.5)-, nitric oxide synthase (NOS)-, galanin- and vasoactive intestinal peptide (VIP)-immunoreactive nerve fibers were present in the epithelium, lamina propria, smooth muscle layer and tunica adventitia. In the tunica adventitia, many PGP 9.5- and NOS-immunoreactive neurons were found singly or in small ganglia, while some VIP- and galanin-immunoreactive neurons were observed. A few PGP 9.5- and NOS-immunoreactive neurons were found in the submucosal layer. These results suggest that the trachea of the large flying fox has a rigid structure of tracheal rings and that the posterior two-thirds of the trachea probably contract via the actions of smooth muscles innervated with peptidergic or nitrenergic neurons that are located in tracheal ganglia, whereas the anterior third is non-mobile.  相似文献   

14.
This study documents the population status and behaviour of the Indian Flying Fox (Pteropus giganteus) at two locations in the temperate environment of the Kathmandu Valley, Nepal. During the five-month study, from 14th July, 2014 to 2nd January, 2015, peak populations were observed in October, 2014 at Sallaghari (1550 individuals) and Keshar Mahal (949 individuals). The behavioural study resulted in 1130 observed events of 10 different behavioural activities at Sallaghari and 1158 events of the same activities at Keshar Mahal. Sleeping, grooming, wing spreading and wing flapping were frequently observed at both study sites. The behaviour of P. giganteus is influenced by the weather and air temperature irrespective of hours of the day and date of observation. Habitat destruction, lack of food, pollution and misconception were the major threats to P. giganteus perceived by local people in course of interviews. Knowledge regarding the population size and behaviours of wildlife species is essential to understand the conservation needs for the survival and management of wild animals and their habitat. This study provides baseline information for two populations of Indian flying fox (P. giganteus) in Kathmandu Valley Nepal.  相似文献   

15.
The karyotypes of 4 species of bats, Artibeus lituratus (Phyllostomatidae), Pipistrellus pipistrellus (Vespertilionidae), Pteropus alecto and P. giganteus (Pteropodidae), were studied after several banding techniques. For A. lituratus, in which an X-autosome translocation was observed, an analyse of the replication pattern in the rearranged chromosome was also made after BrdU incorporation.  相似文献   

16.
Many lizards use femoral gland secretions in intraspecific communication. Although there is a consistent interspecific variation in chemical composition of secretions, considerable variation is also often found between populations, which may affect conspecifc recognition and lead to speciation processes. Balearic lizards (Podarcis lilfordi) are currently distributed only in several isolated islets offshore of the main islands with different environmental conditions (vegetation, diet, density of population, etc). Also, there is a high genetic variability between populations. We examined whether there was a similar variation in the composition of the femoral secretions of male lizards, and which could be the causes of such variation. By using GC–MS analyses, we found 75 lipophilic compounds in femoral gland secretions of male P. lilfordi from three representative island populations. Main compounds were steroids (94.4%), mainly cholesterol, but we also found alkanes, ketones, waxy esters, squalene, carboxylic acids and their ethyl esters, alcohols and other minor compounds. However, there were clear differences between populations with respect to the number and relative proportions of compounds. Using the patterns of presence and abundance of compounds in secretions it is possible to predict the population of origin of a lizard. We discuss how these differences could be explained considering genetic and environmental differences between populations.  相似文献   

17.
Although flying foxes (fruit bats in the genus Pteropus ) in continental forests often fly between scattered resources, little is known about their ranging behavior among islands. The inhospitable water matrix that surrounds the food patches (islands) in archipelagos may prevent flying foxes from tracking resources as efficiently as their counterparts on larger landmasses do. Our aim in this study was to determine whether the abundance of foraging flying foxes ( Pteropus tonganus ) reflected food availability on islands in the Vava'u archipelago of Tonga, regardless of island size and isolation. Overall, food availability was the strongest determinant of flying fox abundance, and spatial aspects of the islands (land area within 10 km) had only a small influence. Food availability appears to regulate flying fox abundance only when food resources are low, but when food sources are plentiful, flying fox abundance may be high or low. These results provide indirect evidence that flying foxes are able to track food resources efficiently in an archipelago, and the water matrix that surrounds the food patches (islands) is not a strong deterrent for foraging animals.  相似文献   

18.
The diet of the Pemba flying fox Pteropus voeltzkowi , a species endemic to the island of Pemba off Tanzania, was investigated. Faecal pellets, ejecta and dropped fruits were collected from under roosts to facilitate dietary analysis. This was supplemented by data from local villagers and school students. The main component of the diet was mango ( Mangifera indica ), but bats also ate breadfruit ( Artocarpus altilis ), figs ( Ficus spp.), flowers, leaves, and other fruit. Pollen from at least five plant species was also found in faecal pellets. Pteropus voeltzkowi may be one of the only species on the island that disperses larger seeds. The germination rate of bat‐ingested seeds was higher than that for seeds from ripe fruit, and this appeared to be linked to selective ingestion of viable seeds by bats.  相似文献   

19.
To test flying fox adaptations to a habitat mosaic with extreme deforestation, the abundance, habitat choice and feeding behavior of the Pacific flying fox, Pteropus tonganus, were investigated across 16 islands of the Yasawa archipelago, Fiji. The habitat mosaic is formed by 4.3 percent tropical dry forest and 3.3 percent farmland, leaving exotic grasslands and stands of Leucaena leucocephala to overrun the vast majority of land. Pteropus tonganus abundance was high (5757 bats) despite deforestation and hunting. Roosting sites were restricted to native forest fragments. Grasslands and stands of L. leucocephala were completely void of bats at all times. The mean foraging density in farmland was four times higher than in forests and foraging competition was routinely observed in farmland but was extremely rare in forests. The author suggests that during the study, extensive foraging in farmland was supporting the high P. tonganus population. Additionally, the preferential foraging in farmland was responsible for the low foraging densities within forests and dramatically less intraspecies competition for forest resources. Further research is needed on seed dispersal within forests and to test for seasonal variations in bat abundance and feeding.  相似文献   

20.
The taxonomy, biology, and population status of flying foxes (Pteropus spp.) remain little investigated in the Caroline Islands, Micronesia, where multiple endemic taxa occur. Our study evaluated the taxonomic relationships between the flying foxes of the Mortlock Islands (a subgroup of the Carolines) and two closely related taxa from elsewhere in the region, and involved the first ever field study of the Mortlock population. Through a review of historical literature, the name Pteropus pelagicus Kittlitz, 1836 is resurrected to replace the prevailing but younger name Pteropus phaeocephalus Thomas, 1882 for the flying fox of the Mortlocks. On the basis of cranial and external morphological comparisons, Pteropus pelagicus is united taxonomically with Pteropus insularis “Hombron and Jacquinot, 1842” (with authority herein emended to Jacquinot and Pucheran 1853), and the two formerly monotypic species are now treated as subspecies — Pteropus pelagicus pelagicus in the Mortlocks, and Pteropus phaeocephalus insularis on the islands of Chuuk Lagoon and Namonuito Atoll. The closest relative of Pteropus pelagicus is Pteropus tokudae Tate, 1934, of Guam, which is best regarded as a distinct species. Pteropus pelagicus pelagicus is the only known resident bat in the Mortlock Islands, a chain of more than 100 atoll islands with a total land area of <12 km2. Based on field observations in 2004, we estimated a population size of 925–1,200 bats, most of which occurred on Satawan and Lukunor Atolls, the two largest and southernmost atolls in the chain. Bats were absent on Nama Island and possibly extirpated from Losap Atoll in the northern Mortlocks. Resident Mortlockese indicated bats were more common in the past, but that the population generally has remained stable in recent years. Most Pteropus phaeocephalus pelagicus roosted alone or in groups of 5–10 bats; a roost of 27 was the largest noted. Diet is comprised of at least eight plant species, with breadfruit (Artocarpus spp.) being a preferred food. Records of females with young (April, July) and pregnant females (July) suggest an extended breeding season. Pteropus pelagicus pelagicus appears most threatened by the prospect of sea level rise associated with global climate change, which has the potential to submerge or reduce the size of atolls in the Mortlocks. Occasional severe typhoons probably temporarily reduce populations on heavily damaged atolls, but hunting and ongoing habitat loss are not current problems for the subspecies.  相似文献   

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