雉鸡(Phasianus colchicus)营巢生境的模拟分析研究

将多元统计学方法与地理信息系统结合对动物的栖息地进行适宜性分析,是近年动物栖息地研究者和管理者都十分感兴趣的方面。本研究采用马氏距离法,利用地理信息系统模拟甘肃雉鸡的营巢生境。模拟结果表明,与已知营巢生境相似水平为0.95的区域面积,仅占整个研究区的0.68%,而与已知营巢生境迥然不同（P＜0.05）的区域面积占79.08%。营巢生境与非营巢生境在生境类型组成和地形因素上存在多方差异,营巢生境中农田和草坡占有极大比例,用于营巢的区域总是更接近生境的边缘。特别是接近于农田、草坡和白桦阔叶林等生境,表明倾向于在这几种生境的边缘附近营巢。营巢生境的平均海拔比非营巢生境低,坡度也较缓,坡向则更偏于东南方。在同一生境类型内部,用于营巢的区域和不利用的区域之间也存在很大差别,营巢区域总是更接近生境的边缘。某一生境周围的其它生境类型也会影响雉鸡的营巢选择。     

MHC genotype predicts mate choice in the ring-necked pheasant Phasianus colchicus

Females of several vertebrate species selectively mate with males on the basis of the major histocompatibility complex (MHC) genes. As androgen-mediated maternal effects have long-lasting consequences for the adult phenotype, both mating and reproductive success may depend on the combined effect of MHC genotype and exposure to androgens during early ontogeny. We studied how MHC-based mate choice in ring-necked pheasants (Phasianus colchicus) was influenced by an experimental in ovo testosterone (T) increase. There was no conclusive evidence of in ovo T treatment differentially affecting mate choice in relation to MHC genotype. However, females avoided mating with males with a wholly different MHC genotype compared with males sharing at least one MHC allele. Females also tended to avoid mating with MHC-identical males, though not significantly so. These findings suggest that female pheasants preferred males with intermediate MHC dissimilarity. Male MHC heterozygosity or diversity did not predict the expression of ornaments or male dominance rank. Thus, MHC-based mating preferences in the ring-necked pheasant do not seem to be mediated by ornaments' expression and may have evolved mainly to reduce the costs of high heterozygosity at MHC loci for the progeny, such as increased risk of autoimmune diseases or disruption of coadapted gene pools.     

Responses of ring-necked pheasant chicks (Phasianus colchicus) to conspecific calls

The locomotor responses of pheasant chicks to conspecific calls and the vocalizations of the chicks relating to their locomotor responses were measured in a test apparatus permitting approach or retreat movements. The brood-gathering call and the content call elicited strong approach from chicks. The alarm call and the squeak call inhibited locomotion in chicks. The hiss call, brood-caution call, fright call and flock call do not greatly affect the locomotion of subjects. The flock call appears to be primarily a care-soliciting call. Conspecific calls appear to be important to the survival of young pheasant chicks in the wild.     

Molecular heterosis at the conalbumin locus in the ring-necked pheasant (Phasianus colchicus)

Summary Egg whites of Phasianus colchicus containing conalbumin of the heterozygous type show a stronger inhibitory effect on the growth of Saccharomyces cerevisiae than egg whites with conalbumin of the common homozygous type. This fact is interpreted as an example of heterosis at the molecular level.     

Winter foraging habitat selection of brown-eared pheasant (Crossoptilon mantchuricum) and the common pheasant (Phasianus colchicus) in Huanglong Mountains, Shaanxi Province

The foraging habitat selections of brown-eared pheasant (Crossoptilon mantchuricum) and the common pheasant (Phasianus colchicus) were studied in Huanglongshan Nature Reserve Shaanxi, China. Foraging habitat characteristics were measured on the basis of expected differences between species at 183 sites from November to December 2006 and January 2007. The results showed that both species selected foraging habitats with altitude (<1200 m), conifer forest, half sunny and half shady slope, sunny slope, density of trees (<5 individuals/100 m²), cover of shrub (>50%), visibility class (<10%) and distance to water source (<300 m). However, the brown-eared pheasant selected habitats with cover of trees (30–50%), middle or lower slope location, distance to edge of woods (<300 m) and human disturbance (<500 m), and the selection on density of shrub was not observed, compared to the selections on cover of trees (<30%), lower slope location, distance to edge of woods (<500 m) and human disturbance (<300 m), and density of shrub (>500 individuals/100 m²) for common pheasant. We also found that the common pheasant avoid predators by concealment whereas brown-eared pheasant evade predations by running away strategy.     

Experimental manipulation of yolk testosterone affects digit length ratios in the ring-necked pheasant (Phasianus colchicus)

In humans, most of the mammals and one bird species studied so far, the relative length of individual digits is sexually dimorphic. Most studies of humans have been concerned with the ratio between second (2D) and fourth digits (4D), whereas some studies of humans and other mammals have also investigated other digit ratios. Inter- and intra-sexual variation in 2D:4D may depend on differential exposure to androgens during embryonic life, and the genetic mechanisms linking 2D:4D to androgens may be mediated by Hox genes. Because Hox genes are conserved in vertebrates, similar patterns of variation in digit ratios might be expected across vertebrate classes. The observation of correlations between digit ratios and physiological, psychological and performance traits in humans has generated interest in exploring the possibility that digit ratios are a marker of embryonic exposure to androgens, which have diverse consequences on several phenotypic traits. However, the hypothesis that digit ratios depend on androgen effects during development has never been tested experimentally. In this study, we increased testosterone concentration in ring-necked pheasant eggs and measured length ratios between the second, third and fourth digits of both feet in fully grown offspring. Females from testosterone-injected eggs had larger 2D:3D in the left foot, whereas this was not the case in males. The other digit ratios were unaffected by hormone treatment in both sexes. However, digit ratios showed no sexual dimorphism among controls. Thus, present results are consistent with the hypothesis that variation in testosterone levels during development affects digit ratios.     

Mercury accumulation in the muscles and feathers of pheasants, Phasianus colchicus (L. 1758)

Mercury concentrations were determined in muscles and feathers of 58 cock pheasants. Birds were collected from seven different polluted sites in southern Poland in 1987. The mercury concentrations in the muscle ranged from 0.010 to 0.026 mug g dry mass. The significantly highest values were found in muscle samples from Przylasek and Przemysl. The levels found in the flight feathers were higher than in breast feathers. Average concentrations in flight feathers ranged from 0.050 mug g (Przemysl) to 0.240 mug g dry mass (Przylasek). © Rapid Science 1998     

Sexual segregation in winter, spring dispersal and habitat use in the pheasant (Phasianus colchicus)

Sexual segregation, spring dispersal and late winter to spring habitat selection were studied in the pheasant Phasianus colchicus L. on two areas for which the proportions of different habitats were similar. On one of the sites (Damerham) hand-reared pheasants were released for shooting. On the other (Fulwell) no releasing or shooting took place.
The sex ratio of birds feeding in fields in autumn favoured males because females fed in groups within woods. Groups of birds were significantly segregated by sex during early to late winter periods, but by late March they were not. Male groups and solitary males in winter were more evenly dispersed than female groups.
At Fulwell, female winter groups consisted of regular group members (mainly adults) and transitory individuals called 'drifters' (mainly immatures).
Females in their first breeding attempt dispersed further from their winter range to their breeding range than did adult females and females dispersed further than males. Males gaining a territory for the first time moved significantly further than old territory owners. Territorial males moved less than non-territorial males between successive spring ranges.
During March June, habitat use by 33 radio-tagged females changed markedly from mixed and deciduous woodland to fields sown with winter and spring corn. The implications for management are outlined.     

Mapping of a candidate region for susceptibility to inclusion body myositis in the human major histocompatibility complex

 Inclusion body myositis (IBM) is a form of idiopathic inflammatory myopathy of unknown aetiology. A strong association with HLA class II (HLA-DR3) suggested a role for genes in the human major histocompatibility complex (MHC) in the predisposition to this disease. In this study, we have taken advantage of the ancestral haplotype (AH) concept and historical recombinations to map for a possible susceptibility gene(s) in the MHC. We performed detailed typing of three MHC-related HSP70 genes and defined allelic combinations in the context of MHC AH. We also modified existing methods to give a simple and accurate method for typing two TNF microsatellites. Using the HSP70 and TNF markers and HLA-DR, –B, and C4 typing of our patients with IBM, we defined a potential site for the MHC-associated susceptibility gene(s) in the region between HLA-DR and C4. Received: 16 July 1998 / Revised: 14 January 1999     

Detection and characterization of primordial germ cells in pheasant (Phasianus colchicus) embryos

The developmental similarity between the chicken and pheasant (Phasianus colchicus) allows the novel biotechnologies developed in the chicken to be applied to the production of transgenic pheasants and interspecies germline chimeras. To detect pheasant primordial germ cells (PGCs) efficiently, which is important for inducing germline transmission, the ultrastructure of PGCs and their reactivity to several antibodies (2C9, QB2, anti-SSEA-1, and QCR1) and periodic acid-Schiff's solution (PAS) were examined. To obtain PGCs, blood was taken from embryos incubated for 62-72 h or from gonads from embryos incubated for 156-216 h. The PGCs collected from both sources had the typical ultrastructure of pluripotent cells: a large nucleus with a distinct nucleolus, a high ratio of nuclear to cytoplasmic volume, and a distinct cytoplasmic membrane. In comparing the morphology of PGCs collected from different sites, more mitochondria and better-developed membrane microvilli were found in gonadal PGCs than in circulating PGCs. The nucleus of gonadal PGCs was flattened and had a large eccentrically positioned nucleolus. Of the antibodies tested, only QCR1 antibody reacted with an epitope in pheasant PGCs, and no specific signal was detected to other antibodies. The temporal change in the PGC populations in the blood and gonads of embryos was examined. In blood, the population was greater (P < 0.0001) in embryos incubated for 64 h than in embryos incubated for 62 or 66-72 h (31.4 versus 5.6-16.2 microL(-1)). In embryonic gonads, the number of PGCs increased continuously from 156 to 216 h of incubation (193-2,718 cells/embryo), although the ratio of PGCs to total gonadal cells did not change significantly (0.50-0.61%). In conclusion, pheasant PGCs have typical germ cell morphology and possess the QCR1 epitope. Circulating blood and the gonads of embryos incubated for 64 and 216 h, respectively, are good sources of PGCs.     

Hotspots of meiotic recombination in the mouse major histocompatibility complex

Meiotic recombination is not random in the proximal region of the mouse major histocompatibility complex (MHC). It is clustered at four restricted positions, so-called hotspots. Some of the MHC haplotypes derived from Asian wild mice enhance recombination at the hotspots in genetic crosses with standard MHC haplotypes of laboratory mouse strains. In particular, the wm7 haplotype derived from Japanese wild mouse indicated an approximately 2% recombination frequency within a 1.2 kb fragment of DNA in the interval between the Pb and Ob genes. Interestingly, this enhancement of recombination was observed only in female meiosis but not in male meiosis. Mating experiments demonstrated that the wm7 haplotype carries a genetic factor in the region proximal to the hotspot, which instigates recombination. In addition, the wm7 haplotype has a genetic factor located in the region distal to the hotspot, which suppresses recombination. From the molecular characterization of the two hotspots located in the Eb gene and the Pb-Ob interval, it appeared that there are several common molecular elements, the consensus of the middle repetitive MT-family, TCTG or CCTG tetramer repeats, and the solitary long terminal repeat (LTR) of mouse retrovirus.     

Olfactory cues associated with the major histocompatibility complex

Besides its immunological function of self/non‐self discrimination the major histocompatibility complex (MHC) has been recognized as a possible source of individual specific body odors. Dating back to speculations on the role of the extraordinary polymorphism of the MHC as background of an individual chemosensory identity and to early observations of MHC‐dependent mate choice in inbred strains of mice, systematic experimental studies revealed a first evidence for H‐2 related body odors in this species. Meanwhile a large number of animal studies with rodents and a series of field studies and experiments with humans have extended our knowledge of MHC‐related odor signals and substantiated the hypothesis of immunogenetic associated odortypes. These results suggest that the most prominent feature of the MHC, its extraordinary genetic diversity, seems in part to be selectively maintained by behavioral mechanisms which operate in contemporary natural populations. The high degree of heterozygosity found in natural populations of most species seems to be promoted by non‐disease‐based selection such as mating preferences and selective block of pregnancy. This revised version was published online in July 2006 with corrections to the Cover Date.     

Subspecies boundaries and recent evolution history of the common pheasant (Phasianus colchicus) across China

The mitochondrial DNA (mtDNA) control region of two hundreds and thirty-six common pheasants (belonging to fourteen subspecies collected at twenty-eight localities) was used to investigate the subspecies status of Phasianus colchicus. Eighty-nine variable sites defined one hundred and thirty-nine haplotypes. Phylogenetic analysis of haplotypes revealed that P. c. shawii, P. c. mongolicus and P. c. suehschanensis were monophyletic. P. c. shawii and P. c. mongolicus were isolated by the Taklimakan, the Bardain, the Jaran and the Gurbantonggut Deserts where the two subspecies evolved independently. P. c. suehschanensis was isolated by the forest and mountains in the Sichuan Basin where it evolved independently. Further eleven subspecies were identified and split into the western and eastern groups. The divergence occurred in the late Pleistocene when the arid, semi-arid and monsoon regions formed, and it was induced by the isolation from the Qinling and Taihang Mountains. Fst-values decreased from 0.543 (for twenty-eight populations) to 0.541 (for fourteen subspecies). In light of these results, we suggest that the currently recognized subspecies do not reflect the evolutionary history of the common pheasant.     

Light and electron microscopy observations in the thyroid gland of the pheasant (Phasianus colchicus L.)

In the summer, the pheasant thyroid presents as a relatively quiescent organ with reduced secretory activity; the follicular epithelium is very low and mostly of the pavement type, while the follicles are unwontedly large and contain an increased amount of colloid. The follicular cell cytoplasm contains numerous characteristic spherical vacuolar structures. In the winter, however, the thyroid displays remarkable reconstruction and raised activity of the follicular cells, which are much higher and columnar; the small follicles contain less colloid. Peculiar rod-like or fusiform structures, some measuring up to 6,5 microgram, were observed in the cytoplasm of the follicular cells of both hen and cock pheasants in November and March. At the beginning of the winter (November), specific dark cells with pycnotic nuclei, evidently in process of degeneration, appeared in the follicular epithelium. In March, specific granulated cells (probably parafollicular cells) were found sporadically in the immediate vicinity of the wall of subcapsular follicles in cock pheasant.     

Presentation of antigenic peptides by products of the major histocompatibility complex

Molecules encoded by the major histocompatibility complex (MHC) are polymorphic integral membrane proteins adapted to the presentation of peptide fragments of foreign antigens to antigen-specific T-cells. The diversity of infectious agents to which an immune response must be mounted poses a unique problem for receptor–ligand interactions; how can proteins whose polymorphism is necessarily limited bind an array of peptides almost infinite in its complexity? Both MHC class I and class II determinants have achieved this goal by harnessing a limited number of peptide side chains to anchor the epitope in place while exploiting conserved features of peptide structure, independent of their primary sequence. While class I molecules interact predominantly with the N- and C-termini of peptides, class II determinants form an extensive hydrogen bonding network along the length of the peptide backbone. Such a strategy ensures high-affinity binding, while selectively exposing the unique features of each ligand for recognition by the T-cell receptor. © 1998 European Peptide Society and John Wiley & Sons, Ltd.     

Body weight and some biometrical traits of ring-necked pheasants (Phasianus colchicus) at different ages

Although the growth of pheasants is an important issue, there are few publications providing information on body weight and morphometrics of pheasants at different ages. The aim of this study was to investigate body weight, tarsus length, wing length and wingspan in farmed pheasants aged 3-16 weeks. The study was carried out on 50 pheasants (31 females and 19 males). All one-day old birds were marked and kept until the 16th week of life. In the 3rd 8 h 12th and 16th weeks of life all pheasants were weighted and tarsus length, wing length and wingspan were measured. Male chicks appeared to be significantly heavier than females (P< or = 0.01) already in the third week of life. Also their wings were longer and their wingspan attained higher values (P < or = 0.05). Absolute gains of the majority of traits also differed between sexes (being larger in males) in all studied periods. Values of body weight, tarsus length and wingspan noted in the third week of life were significantly correlated with all later measurements. Thus body weight and some biometrical traits of pheasant chicks measured already at the 3rd week of life could be applied as predictors of future body weight and size.     

Plumage microbiota covaries with the major histocompatibility complex in blue petrels

To increase fitness, a wide range of vertebrates preferentially mate with partners that are dissimilar at the major histocompatibility complex (MHC) or that have high MHC diversity. Although MHC often can be assessed through olfactory cues, the mechanism by which MHC genes influence odour remains largely unclear. MHC class IIB molecules, which enable recognition and elimination of extracellular bacteria, have been suggested to influence odour indirectly by shaping odour‐producing microbiota, i.e. bacterial communities. However, there is little evidence of the predicted covariation between an animal's MHC genotype and its bacterial communities in scent‐producing body surfaces. Here, using high‐throughput sequencing, we tested the covariation between MHC class IIB genotypes and feather microbiota in the blue petrel (Halobaena caerulea), a seabird with highly developed olfaction that has been suggested to rely on oduor cues during an MHC‐based mate choice. First, we show that individuals with similar MHC class IIB profiles also have similar bacterial assemblages in their feathers. Then, we show that individuals with high MHC diversity have less diverse feather microbiota and also a reduced abundance of a bacterium of the genus Arsenophonus, a genus in which some species are symbionts of avian ectoparasites. Our results, showing that feather microbiota covary with MHC, are consistent with the hypothesis that individual MHC genotype may shape the semiochemical‐producing microbiota in birds.