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1.
The secondary sex ratio in sable Martes zibellina L. maintained in captivity was estimated for the first time ever. The data obtained at the Pushkin pedigree breeding farm (Moscow oblast) in 1982 through 1987 were analyzed. In total, 1705 litters of 418 females were examined. The total frequency of male births (P^ was 0.527 ± 0.007; the 95% confidence interval of P^ (the probability of birth of a male) was within the limits 0.513 p 0.541, and the deviation from the expected 1 : 1 ratio was statistically significant. No effect of parental age and litter size on the number of male progeny was found. This may indicate a small influence of the parental hormonal and immunological status on sex ratio, which was reported in many other mammal species including those related to sable. Apparently, there is an evolutionary mechanism underlying the stable excess of males in sable litters.  相似文献   

2.
Monakhov VG 《Genetika》2001,37(9):1281-1289
Using standard and mulivariate statistic methods, an epigenetic character--foramina in fossa condyloidei inferior, FFCI--was studied in sable populations. This character was shown to be most frequent in southeastern populations of the species (Primorye and the Baikal region) while its distribution in the remaining part of the range was polyclinal. The expression of FFCI was directly associated with coat color and longitude, and inversely associated with skull size. This trend was broken by some western populations formed in the 1950s by introduction, which exhibited stable morphological differences with adjacent aboriginal sable populations. Most populations of the species exhibit differences in the manifestation of the character. Frequency of the FFCI manifestation can be used as an additional population characteristic, an associative diagnostic character that shows high discriminating capability in detecting phenogenetic relationships of intraspecific groups.  相似文献   

3.
Associations between some characteristics of fitness (the age of the first reproduction, life span, fertility, and the number of missed pregnancies) and heterozygosity for some allozyme loci have been studied in a population of the sable Martes zibellina L. kept in cages at a farm. Of all fitness characteristic studied, a weak correlation has only been found between heterozygosity and the age of the first reproduction (maturation rate). The age of the first reproduction is positively associated with the life span and fertility. The results obtained are discussed in terms of the relationship between the genetic variation of longevity and developmental rate and prospects of their application to breeding practice.  相似文献   

4.
The first comparison of mitochondrial variations in sables from captive and natural populations of the Urals, Central Siberia, Yakutia, Kamchatka, and Japan has been performed. The object of comparative analysis was a 427-bp 5' fragment of the mitochondrial control region, including the D-loop. Two main haplogroups of the sable mitochondrial genome have been found, which provides new data for reconstruction of the spread of the sable over its current range. Asymmetry of the haplotype abundances in the captive populations of sables has been detected. The mitochondrial haplotypes characteristic of sable breeds have been identified. The possible role of the frequent mitochondrial haplotypes of the captive population in the sable adaptation to the conditions of captivity is discussed.  相似文献   

5.
6.
The aim of this study was to investigate whether the actively wintering Palearctic sable Martes zibellina has evolved physiological adaptations to tolerate nutritional scarcity. Sixteen farm-bred male sables were divided into a fed control group and an experimental group fasted for 4 days. The rate of weight loss in the sable was similar to other medium-sized mustelids. Fasting led to hypoglycaemia and to a decreased lymphocyte percentage. The sable derived metabolic energy from both subcutaneous and intraabdominal white adipose tissues and the relative decrease in fat mass was the largest for the retroperitoneal and subcutaneous depots. Metabolic energy derived partly from body proteins indicated by the increased plasma levels of urea, uric acid and total essential amino acids. Triacylglycerols accumulated in the livers of the fasted sables and the increased plasma aminotransferase activities suggested hepatic dysfunction. The decreased plasma insulin concentrations and the elevated cortisol levels probably contributed to stimulated lipolysis and protein catabolism. Moreover, fasting increased the plasma ghrelin concentrations of the sables and down-regulated the thyroid activity.  相似文献   

7.
The high value of sable (Martes zibellina L.) fur and stable demand for it over the centuries have led to suboptimal hunting patterns and, as a result, considerable fluctuations in the sizes of natural populations of this species. To maintain the traditional export of sable fur, efforts towards commercial domestication of sable have been made in Russia. The first farm population of sable consisted of animal from eight natural populations in 1929. After the problems related to breeding in captivity were solved, directional selection began. Eighty years of breeding have resulted in sable herds with homogeneous quantitative characters. Prospects for further breeding depend on the current level of genetic diversity in the captive populations of sables formed during the first stages of domestication. The sable populations of the Pushkinsky and Saltykovsky fur farms located in Moscow oblast, which were the objects of this study, are the progenitors of the existing captive populations. The first estimation of genetic variation of this species by means of a panel of microsatellite markers was developed for this study. Two captive sable populations were analyzed using ten microsatellite loci; a total of 75 alleles were found in both populations. Population-specific alleles were identified (6 and 13 in the Pushkinsky and Saltykovsky populations, respectively). The populations studied were found to be differentiated with respect to four microsatellite loci.  相似文献   

8.
Beketov SV  Kashtanov SN 《Genetika》2002,38(2):243-250
The secondary sex ratio in sable Martes zibellina L. maintained in captivity was estimated for the first time ever. The data obtained at the Pushkin pedigree breeding farm (Moscow oblast) in 1982 through 1987 were analyzed. In total, 1705 litters of 414 females were examined. The total frequency of male births (P) was 0.527 +/- 0.007; the 95%-confidence interval of p (the probability of birth of a male) was within the limits 0.513 < p < 0.541, and the deviation from the expected 1:1 ratio was statistically significant. No effect of parental age and litter size on the number of male progeny was found. This may indicate a small influence of the parental hormonal and immunological status on sex ratio, which was reported in many other mammal species including those related to sable. Apparently, there is an evolutionary mechanism underlying the stable excess of males in sable litters.  相似文献   

9.
The relationship between the response to artificial selection for darker coat color and fitness in a farm population of the sable (Martes zibellina L.) from the Pushkinskoe Fur Farm (Moscow oblast) was studied. The selection was performed during 41 years. By the moment of the study, a response to the selection for this character had been obtained: the coat color in the selected population had become darker, and the proportion of black animals in it increased. In addition, sables with black heads, which were absent in the original population, had appeared. Artificial selection was accompanied by a decrease in the fitness of the selected population, which was expressed in decreased female reproductive capacity parameters (the fertility, maturation rate, and duration of the reproductive period). A selection technique consisting in the use of only highly fertile animals in the selection originally made it possible to restore the fitness parameters to the initial level almost without a decrease in the dark shade of the fur. However, further selection led to a drastic decrease in fitness that could not be precluded by any selection method used. The possible ways to overcome this unfavorable effect of artificial selection are discussed.  相似文献   

10.
In the course of a study of the evolution of a genus of African flycatchers, Batis, numerical techniques were employed to analyse the characters of the populations of the forest-dwelling Batis and to throw some light on their relationships. The techniques reported upon in this paper are non-metric multidimensional scaling (MDS) and the Unweighted Pair-group Method using Arithmetic Averages (UPGMA). The results obtained from these numeric analyses closely parallel those using non-quantitative methods.  相似文献   

11.
伞形科囊瓣芹属的表型分析   总被引:1,自引:0,他引:1  
选取伞形科(Apiaceae)囊瓣芹属(Pternopetalum Franchet)32个分类群的60个形态学性状,利用DELTA系统的UPGMA算法进行了聚类分析。结果表明属下形成以五匹青(P.vulgare(Dunn)Hand.-Mazz.)和东亚囊瓣(P.tanakae(Franchet&Sav.)Hand.-Mazz.)为代表的两个主要表征群。两个主要表征群的分类结构和各自所包含的类群基本相应于前人研究中本属两个组的属下处理。根据全面相似性分析的结果和部分形态学特征的评估,确认了属下6个种的复合群:即五匹青、囊瓣芹(P.davidii Franchet)、散血芹(P.botrychioides(Dunn)Hand.-Mazz.)、洱源囊瓣芹(P.molle(Franchet)Hand.-Mazz.)、澜沧囊瓣芹(P.de-lavayi(Franchet)Hand.-Mazz.)和东亚囊瓣芹复合群。根据形态学特征在表型树上的分布分析表明:伞形花序的着生位置、花柱的形态、花柱基的形状和萼齿的大小等生殖特征可能是属下早期分化的关键性性状。属下主要变异类型(种的复合群和典型狭域特有种)对不同海拔区域和小生境的依赖,以及不显著的形态学分化表明:对横断山区较高的异质性生境的生态适应是囊瓣芹属类群多样化过程后期的一个重要特征。  相似文献   

12.
Phylogenetic analysis of different regions of the mitochondrial genome of the sable showed the presence of several topologies of phylogenetic trees, but the most statistically significant topology is A-BC, which was obtained as a result of the analysis of the mitochondrial genome as a whole, as well as of the individual CO1, ND4, and ND5 genes. Analysis of the intergroup divergence of the mtDNA haplotypes (D xy) indicated that the maximum D xy values between A and BC groups were accompanied by minimum differences between B and C groups only for six genes showing the A-BC topology (12S rRNA, CO1, CO2, ND4, ND5, and CYTB). It is assumed that the topological conflicts observed in the analysis of individual sable mtDNA genes are associated with the uneven distribution of mutations along the mitochondrial genome and the mitochondrial tree. This may be due to random causes, as well as the nonuniform effect of selection.  相似文献   

13.
To develop a reliable approach to pregnancy diagnosis in sables based on noninvasive methods of hormonal status assessment, the concentrations of immunoreactive compounds (IRC) binding with antibodies to progesterone have been measured in the feces of females at different stages of the reproductive cycle. The results show that this concentration is higher in truly pregnant than in mated but nonreproducing females. An increase in the IRC concentration relative to its individual baseline level may be regarded as a reliable indication of true pregnancy.  相似文献   

14.
Potential factors were analyzed that affected the formation of gene pools of two introduced beaver populations founded in the 1940s–1950s by releasing beavers from Voronezh oblast and Belarus into rivers of the Kirov and Novosibirsk oblasts. The populations from these two regions were shown to differ in four allozyme loci (Ahd-2, Gpi, Es-5, and Dia-2). Within Kirov oblast, the samples from three tributaries of the Vyatka River differed in three other loci (Ck-1, Gp-9, and Trf). It is suggested that these features of the allele distribution at these loci are explained by the history of the introduced populations, hybridization between beavers from Voronezh oblast and Belarus, and founder effect during the subsequent artificial and spontaneous migration. Generally, genetic differences between the populations in all studied loci were very small: D = 0.02 between populations from different regions and D = 0.01 between populations from the tributaries of third-order rivers of the Kirov oblast. At the same time, disequilibrium was detected for ten polymorphic loci in the combined sample from the populations of Kirov oblast, which indicates the existence of interpopulation heterogeneity at the level of local populations of fourth- and fifth-order rivers. The unexpected finding of a genetic similarity between one studied individual of Tuvinian beaver subspecies (Castor fiber tuvinicus) and C. f. orientoeuropeas was recorded.  相似文献   

15.
Behavioral polymorphism estimated by the expression of the defensive reaction towards humans has been studied in farm-bred American minks and sables with different color types. Most animals (both minks and sables) from farm populations displayed passive defensive behavior towards humans in the standard hand catch test. Coat color genes have been found to have pleiotropic effects; they influence both the penetrance and expressivity of domestication behavior: in animals with aberrant color types (both sapphire minks and white-and-black sables), the proportion of animals with domestication behavior and the expressivity of this behavior are significantly higher (p <0.01 and p < 0.001, respectively).  相似文献   

16.
Balmysheva NP  Solovenchuk LL 《Genetika》1999,35(12):1681-1686
RFLP analysis of amplified genes for cytochrome b and NADP dehydrogenase 5/6 of sable mtDNA was carried out. Polymorphism was recorded in the first and the second fragment using six and four enzymes, respectively. This allowed us to identify seven mtDNA haplotypes forming two clusters, A1-A3 and B1-C2. The divergence between the clusters was 0.0112-0.0164. An association between mutations of genes for cytochrome b and NADP dehydrogenase 5/6 was established. This association can be explained by high mutability of the fragments containing the associated mutations.  相似文献   

17.
A farm population of the sable Martes zibellina L. has been selected for darker coat color during 40 years. Correlations between fitness characters and correlations of these characters with the selected character have been monitored. Correlation analysis has shown that the female fertility in the first year of reproduction is a promising predictor of how valuable the female will be for further breeding. Artificial directional selection has been shown to change the correlations that have been formed in natural populations of the sable. The relationship of this phenomenon with a decrease in the overall fitness during selection that has been observed in the sable population is discussed.  相似文献   

18.
Colour polymorphism is a recurrent feature of natural populations, and its maintenance has been studied in a range of taxa in their native ranges. However, less is known about whether (and how) colour polymorphism is maintained when populations are removed from their native environments, as in the case of introduced species. We here address this issue by analyzing variation in colour patterns in recently-discovered introduced populations of the guppy (Poecilia reticulata) in Panama. Specifically, we use classic colour analysis to estimate variation in the number and the relative area of different colour spots across low predation sites in the introduced Panamanian range of the species. We then compare this variation to that found in the native range of the species under low- and high predation regimes. We found aspects of the colour pattern that were both consistent and inconsistent with the classical paradigm of colour evolution in guppies. On one hand, the same colours that dominated in native populations (orange, iridescent and black) were also the most dominant in the introduced populations in Panama. On the other, there were no clear differences between either introduced-low and native low- and high predation populations. Our results are therefore only partially consistent with the traditional role of female preference in the absence of predators, and suggest that additional factors could influence colour patterns when populations are removed from their native environments. Future research on the interaction between female preference and environmental variability (e.g. multifarious selection), could help understand adaptive variation in this widely-introduced species, and the contexts under which variation in adaptive traits parallels (or not) variation in the native range.  相似文献   

19.
20.
The relative abundance of intrapopulation groups with different parameters of skull size, coat color, and expression of an epigenetic cranial trait was compared in autochthonous, reintroduced, and donor populations of sable. Recovery of the species resources and broad variability of the phenotypic trait complex in the newly fomned populations were observed. A large proportion of the animals had the phenotype that included large size, dark coat color, and pronounced expression of a specific phene trait (foramen in the condylar fossa) and was not characteristic of the neighboring autochthonous populations. It is reasonable to attribute the presence of individuals with an unusual morphology in the newly formed populations of animals to a manifestation of the founder principle, because the effect of this principle was promoted by spatial isolation of the primary foci of translocated animals.  相似文献   

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