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1.
The objective of this study was to use pedigree analysis to evaluate the population structure and genetic variability of the Mazandaran native fowls in Iran by quantifying the pedigree completeness index, effective population size, genetic diversity, inbreeding level, and individual increase in inbreeding. The pedigree completeness analysis showed 3.31 full, 10.19 maximum, and 6.30 equivalent generations. The effective number of founders (f e) was 131, representing 5% of the potential number of founders. The effective number of ancestors (f a) was 81, and the genetic contribution of the 37 most influent ancestors explained 50% of the genetic variability in the population. The ratio f e/f a (effective number of founders/effective number of ancestors), which expresses the effect of population bottlenecks, was 1.62. The inbreeding coefficient increased over generations and the average was 1.93%. The average relatedness coefficient between individuals of the population was estimated to be 2.59%. The effective population size, based on the number of full generations, was 56. Family size analysis showed that fewer males than females were used, resulting in the observed levels of inbreeding. Average inbreeding coefficient in the Mazandaran native fowls can be regarded to be below critical levels. However, considering the relationship coefficients of individuals is recommended to aid maintaining genetic diversity of Mazandaran native fowls.  相似文献   

2.
The genetic structure of 4 Colombian Creole cattle breeds, namely, Coste?o con Cuernos, Blanco Orejinegro (BON), Romosinuano (ROMO), and Sanmartinero (SM), was studied with an analysis of the available pedigree data. The comparison between the effective number of founders (f(e)) and the effective number of ancestors (f(a)) revealed a decrease in the genetic variation that was rather important for the ROMO and San Martinero breeds, which had the lowest f(a)/f(e) ratios (0.34 and 0.53, respectively). All breeds showed similar values for the number of equivalent generations traced, ranging from 3.1 in BON to 4.8 in ROMO. These 2 populations also had the lowest and the highest population sizes, respectively. The lowest average inbreeding coefficient considering the whole pedigree was obtained by BON (0.18%), whereas the highest was attained by ROMO (1.22%). Finally, the percentage of individuals with an inbreeding level greater than 6.25% in the reference population was high, indicating that the existing conservation management strategies could be improved to successfully maintain the genetic variability of these populations.  相似文献   

3.
This study aimed to describe the population genetic structure and evaluate the state of conservation of the genetic variability of Santa Inês sheep in Brazil. We used pedigree data of the Santa Inês breed available in electronic processing of the Brazilian Association of Sheep Breeders. A file with 20,206 records, which enabled the calculation of the genetic conservation index (GCI), individual inbreeding coefficient (F), change in inbreeding (ΔF), effective population size (Ne), effective number of founders (?e), effective number of ancestors (?ɑ), generation interval (L), average relatedness coefficient of each individual (AR), and Wright’s F-statistics (F IT, F IS, and F ST). For pedigree analysis and calculation of population parameters, the program ENDOG was used. The average inbreeding coefficient (\( \overline{F} \)) was 0.97% and the mean average relatedness (\( \overline{\mathrm{AR}} \)) 0.49%. The effective numbers of founders and ancestors were, respectively, 199 and 161. The average values of F and AR increased significantly over the years. The effective population size fluctuated over the years concurrently to oscillations in inbreeding rates, wherein N e reached just 68 in the year 2012. The mean average generation interval was 5.3 years. The Santa Inês breed in Brazil is under genetic drift process, with loss of genetic variation. It requires the implementation of a genetic management plan in the herd, for conservation and improvement of the breed.  相似文献   

4.
The Catalonian donkey is one of the most endangered donkey breeds in the world. At present, five main subpopulations exist: AFRAC, which consists of many genetically connected Catalonian localities; Berga, which consists of a single herd located also in Catalunya but under private management; and three minor non‐Catalonian subpopulations (Huesca, Sevilla and Toledo). In this study, we analysed the pedigree information of the Catalonian donkey herdbook to assess the genetic diversity and population structure of the breed. We found that the Catalonian donkey has suffered an important loss of genetic diversity and moderate to high increases of inbreeding because of the abuse of a few individuals in matings. This scenario is mainly characterized by the fact that both the effective number of founders and ancestors for the whole population was 70.6 and 27, respectively, while the equivalent number of founders was 146.5 and the number of ancestors explaining overall genetic variability was 93. In addition, only 14% of animals born between the 1960s and 1970s were significantly represented in the pedigree. Our results also show that subpopulations where breeders exchanged reproductive individuals had low levels of inbreeding and average relatedness. One subpopulation, Berga, was reproductively isolated and showed high levels of inbreeding (F = 7.22%), with average relatedness (AR = 6.61%) playing an important role in increasing the values of these coefficients in the whole pedigree. Using genealogical F‐statistics we have found little evidence of population structuring (FST = 0.0083) with major genetic differences among non‐Catalonian subpopulations.  相似文献   

5.
The aim of the study was to analyse the pedigree information of Thoroughbred horses which were participating in gallop races between 1998 and 2010 in Hungary. Among the 3043 individuals of the reference population there were imported animals from foreign countries (e.g. Germany, England or Ireland) and horses that were born in Hungary. The number of complete generations was 15.64 (varied between 0 for the founders and 25.20), the mean number of full generations was 6.69, and the mean maximum generations were 28.96. The number of founders was 1062, and the effective number of founders was 42. Two hundred and thirty-two founders were born before 1793 (when the stud book of the Thoroughbred breed was closed), therefore these founders are considered as true founders of the breed. These 232 founders were responsible for 88.58% of the gene pool in the reference genome. The significant difference between the number of founders and effective number of founders indicate that the genetic diversity decreased greatly from the founders to the reference population. The number of ancestors was 908 and only 6 of them were responsible for 50% of the genetic diversity in the examined population. The effective number of ancestors was 15.32. From the ratio of the effective number of founders and effective number of ancestors we concluded to a bottleneck effect that characterizes the pedigree under study. Generation interval was more than a year longer for stallions (12.17) than it was for mares (10.64). More than 94% of the individuals in the pedigree were inbred, and the average inbreeding of the population was 9.58%. Considering the changes of the inbreeding status of the examined population 4 large time periods were appointed. The first lasted until 1780, the second period was from 1780 until 1952, the third period was between 1946 and 1998 and the last one was from 1998 until 2008. Rate of inbreeding in the last generation was 0.3%, which forecasts further increase in inbreeding. The effective population size was above 100 in the last 30 generations, proving the genetic diversity did not decrease by a level that would make long-term selection impossible.  相似文献   

6.
The accumulation of inbreeding and the loss of genetic diversity is a potential problem in Holstein dairy cattle. The goal of this study was to estimate inbreeding levels and other measures of genetic diversity, using pedigree information from Iranian Holstein cattle. Edited pedigree included 1 048 572 animals. The average number of discrete generation equivalents and pedigree completeness index reached 13.4 and 90%, respectively. The rate of inbreeding was 0.3% per year. Effective number of founders, founder genomes, non‐founders and ancestors of animals born between 2003 and 2011 were 503, 15.6, 16.1 and 25.7, respectively. It was proven that the unequal founder contributions as well as bottlenecks and genetic drift were important reasons for the loss of genetic diversity in the population. The top 10 ancestors with the highest marginal genetic contributions to animals born between 2003 and 2011 and with the highest contributions to inbreeding were 48.20% and 63.94%, respectively. Analyses revealed that the most important cause of genetic diversity loss was genetic drift accumulated over non‐founder generations, which occurred due to small effective population size. Therefore, it seems that managing selection and mating decisions are controlling future co‐ancestry and inbreeding, which would lead to better handling of the effective population size.  相似文献   

7.
The study of population structure by pedigree analysis is useful to identify important circumstances that affect the genetic history of populations. The intensive use of a small number of superior individuals may reduce the genetic diversity of populations. This situation is very common for the beef cattle breeds. Therefore, the objectives of the present study were to analyze the pedigree and possible inbreeding depression on traits of economic interest in the Marchigiana and Bonsmara breeds and to test the inclusion of the individual inbreeding coefficient (F(i)) or individual increases in inbreeding coefficient (ΔF(i)) in the genetic evaluation model for the quantification of inbreeding depression. The complete pedigree file of the Marchigiana breed included 29,411 animals born between 1950 and 2003. For the Bonsmara breed, the pedigree file included 18,695 animals born between 1988 and 2006. Only animals with at least 2 equivalent generations of known pedigree were kept in the analyses of inbreeding effect on birth weight, weaning weight measured at about 205 d, and BW at 14 mo in the Marchigiana breed, and on birth weight, weaning weight, and scrotal circumference measured at 12 mo in the Bonsmara breed. The degree of pedigree knowledge was greater for Marchigiana than for Bonsmara animals. The average generation interval was 7.02 and 3.19 for the Marchigiana and Bonsmara breed, respectively. The average inbreeding coefficient was 1.33% for Marchigiana and 0.26% for Bonsmara. The number of ancestors explaining 50% of the gene pool and effective population size computed via individual increase in coancestry were 13 and 97.79 for Marchigiana and 41 and 54.57 for Bonsmara, respectively. These estimates indicate reduction in genetic variability in both breeds. Inbreeding depression was observed for most of the growth traits. The model including ΔF(i) can be considered more adequate to quantify inbreeding depression. The inclusion of F(i) or ΔF(i) in the genetic evaluation model may not result in better fit to the data. A genetic evaluation with simultaneous estimation of inbreeding depression can be performed in Marchigiana and Bonsmara breeds, providing additional information to producers and breeders.  相似文献   

8.
9.
The Martina Franca (MF) donkey, an ancient native breed of Apulia, was mostly famous for mule production. The breed was at serious risk of extinction in the 1980s following the decrease in demand for draft animals because they were increasingly replaced by agricultural machinery. Much has been done in the last few decades to safeguard the existing donkey breeds, but the situation remains critical. Successful implementation of conservation measures includes an evaluation of the present degree of breed endangerment, so the aim of this work was to analyze the demographic and genetic parameters of this breed to suggest effective conservation strategies. With a current breed register counting less than 500 recorded animals, the pedigree data set included 1,658 MF donkeys born between 1929 and 2006. Analyses were carried out on the whole data set as well as on a smaller one consisting of 422 living animals. Demographic and genetic variability parameters were evaluated using the ENDOG (v4.6) software. The pedigree completeness level was evaluated as well as the generation length, which was calculated for each of the 4 gametic pathways. This information was obtained from animal birth date records together with those of their fathers and mothers. The effective number of founders (f(e)), the effective number of ancestors (f(a)), the founder genome (f(g)), individual inbreeding (F), average relatedness (AR), and the rate of inbreeding per generation were analyzed to describe the genetic variability of the population. Because pedigree depth and completeness were appropriate, especially regarding the current population, the parameters defining genetic variability, namely, f(e), f(a), f(g), F, and AR, could be reliably estimated. Analysis of these parameters highlighted the endangerment status of the MF donkey. Our special concern was with the increased percentage of males and females exhibiting increased AR values. Moreover, the effective size of the current population, 48.08, is slightly less than the range of the minimum effective size, and the rates of inbreeding per generation found in the current MF population exceed the maximum recommended level of 1%. Such a scenario heightens concerns over the endangered status of the MF breed and calls for proper conservation measures and breeding strategies, such as selecting individuals for mating when relationships are below 12.5%.  相似文献   

10.
Franches‐Montagnes is the only native horse breed in Switzerland, therefore special efforts should be made for ensuring its survival. The objectives of this study were to characterize the structure of this population as well as genetic variability with pedigree data, conformation traits and molecular markers. Studies were focused to clarify if this population is composed of a heavy‐ and a light‐type subpopulation. Extended pedigree records of 3‐year‐old stallions (n = 68) and mares (n = 108) were available. Evaluations of body conformation traits as well as pedigree data and molecular markers did not support the two‐subpopulation hypothesis. The generation interval ranged from 7.8 to 9.3 years. The complete generation equivalent was high (>12). The number of effective ancestors varied between 18.9 and 20.1, whereof 50% of the genetic variability was attributed to seven of them. Genetic contribution of Warmblood horses ranged from 36% to 42% and that of Coldblood horses from 4% to 6%. The average inbreeding coefficient reached 6%. Inbreeding effective population size was 114.5 when the average increase of the inbreeding coefficient per year since 1910 was taken. Our results suggest that bottleneck situations occurred because of selection of a small number of sire lines. Promotion of planned matings between parents that are less related is recommended in order to avoid a reduction of the genetic diversity.  相似文献   

11.
A data set constituting a total of 310,109 Hanoverian warmblood horses was analyzed to ascertain the genetic variability, coefficients of inbreeding, and gene contributions of foreign populations. The reference population contained all Hanoverian horses born from 1980 to 2000. In addition, Hanoverian stallions born from 1980 to 1995 and Hanoverian breeding mares from the birth years 1980 to 1995 with registered foals were analyzed for the same genetic parameters. The average complete generation equivalent was approximately 8.43 for the reference population. The mean coefficient of inbreeding was 1.33, 1.19, and 1.29% for the reference population, stallions, and breeding mares, respectively. The effective number of founders was largest in stallions (364.3) and smallest in the reference population (244.9). The ratio between the effective number of founders and the effective number of ancestors was 3.15 for the reference population, 3.25 for the stallions, and 3.06 for the breeding mares. The effective population size in the Hanoverian warmblood reference population was 372.34. English Thoroughbreds contributed nearly 35% of the genes to the Hanoverian reference population and even slightly greater contributions (39%) to the stallions. Trakehner and Arab horses contributed approximately 8 and 2.7%, respectively, to the Hanoverian gene pool. The most important male ancestors were Aldermann I from the A/E line, Fling from the F/W line, and Absatz from the Trakehner line, whereas the breeding mare Costane had the greatest contribution to the reference population, stallions, and breeding mares. From 1996 onward, the stallions Weltmeyer and Donnerhall had the largest genetic impact on the Hanoverian horse population.  相似文献   

12.
The pedigree of the current Austrian Noriker draught horse population comprising 2808 horses was traced back to the animals considered as founders of this breed. In total, the number of founders was 1991, the maximum pedigree length was 31 generations, with an average of 12.3 complete generations. Population structure in this autochthonous Austrian draught horse breed is defined by seven breeding regions (Carinthia, Lower Austria, Salzburg, Styria, Tyrol, Upper Austria and Vorarlberg) or through six coat colour groups (Bay, Black, Chestnut, Roan, Leopard, Tobiano). Average inbreeding coefficients within the breeding regions ranged from 4.5% to 5.5%; for the colour groups, the coefficients varied from 3.5% to 5.9%. Other measures of genetic variability like the effective number of founders, ancestors and founder genomes revealed a slightly different genetic background of the subpopulations. Average coancestries between and within breeding areas showed that the Salzburg population may be considered as the nucleus or original stock whereas all other subpopulations showed high relationship to horses from Salzburg. The target of draught horse breeding in the 21st century does not meet the breeding concept of maximizing genetic gains any more. Stabilizing selection takes place. In this study, we show that demographic factors as well as structure given by different coat colours helped to maintain genetic diversity in this endangered horse breed.  相似文献   

13.
Abstract

To examine the genetic variation in two endangered Norwegian horse breeds, the pedigree structures were investigated, and key parameters such as inbreeding coefficients, effective population size, effective number of founders, effective number of ancestors and effective number of founder genomes were calculated. The data consisted of 31,142 individuals of the D?le horse and 1973 individuals of the Nordland/Lyngen horse, for which the complete generation equivalent was 10.5 and 7.2, respectively. In both breeds, the pedigree data were more than 98.5% complete in the fourth generation, allowing the rate of inbreeding and the effective population size to be precisely estimated, actually measuring the fractional loss of heterozygosity, comparable across generations (not so for the other measures). The level of inbreeding was about 12% in both breeds, with a rather wavy pattern during the past 50 years in the D?le. Considering the last generations only, the effective population size was found to be 152 in the D?le and 42 in the Nordland/Lyngen. For both populations selection in the future should be based on optimal contribution.  相似文献   

14.
Zebu breeds play an important role in cattle production systems in Brazil. To assess the genetic variability from animals in the Herd Books of Nelore, Gir and Guzerat breeds, generation intervals, inbreeding, effective population size and parameters of gene origin (effective number of founders, ancestors and founder genomes) were calculated using pedigree records from 1938 to 1998. Breed subdivision was quantified by Wright's F -statistics. Calculations were separately carried out for consecutive 4-year intervals in the period 1979–98. Generation interval was around 8 years for the three breeds. Total inbreeding increased in all the breeds reaching values of 2.13%, 2.28% and 1.75%. Effective population size decreased from 85 to 68 in Nelore, from 70 to 45 in Gir and remained nearly constant around 104 in Guzerat. The quantities assessing the number of contributing ancestors decreased with time in all the breeds, and in the last analysed period the most important ancestor accounted for 14%, 3.1% and 4.1% in Nelore, Gir and Guzerat, respectively. Results indicate that the studied breeds are suffering from a loss of genetic variability which can result in negative effects on breeding and conservation purposes.  相似文献   

15.
Because native breeds can serve as genetic resources for adapting to environment changes, their conservation is important for future agroecosystems. Using pedigree analysis, we investigated genetic diversity and inbreeding in Japanese Hokkaido native horses, which have adapted to a cold climate and roughage diet. Genetic diversity was measured as the number of founders and the effective number of founders, ancestors and genomes. All metrics imply a decrease in genetic diversity. A comparison of these metrics suggested that pedigree bottlenecks contributed more than did random gene losses to the reduction of genetic diversity. Estimates of marginal contributions of ancestors suggest that the bottlenecks arose mainly because related stallions had been used for breeding. A tendency for an increase in inbreeding coefficients was observed. F‐statistics revealed that a small effective population size majorly contributed to this increase, although non‐random mating in particular regions also contributed. Because the bottlenecks are thought to have reduced the effective population size, our results imply that mitigation of bottlenecks is important for conservation. To this end, breeding should involve genetically diverse stallions. In addition, to prevent non‐random mating observed in particular regions, efforts should be made to plan mating with consideration of kinships.  相似文献   

16.
A study was conducted to characterize genetic diversity in the Alentejana breed of cattle based on its demographic trends and to investigate the major factors affecting genetic erosion in this breed. Herdbook information collected between 1940 and 2004, including pedigree records on 100,562 animals in 155 herds, was used to estimate demographic parameters. The mean generation intervals were 6.0 +/- 2.4 yr and 6.8 +/- 3.2 yr for sires and dams of calves, respectively. Average inbreeding increased steadily over the period analyzed, with an annual rate of inbreeding of 0.33 +/- 0.004% (P < 0.01) and an effective population size of 23.3. In the reference population (28,531 calves born between 2000 and 2003) the average inbreeding was 8.35 +/- 9.02% and nearly 80% of the calves were inbred, whereas the average relationship among all animals was 0.026 +/- 0.040. Nevertheless, the mean relationship was 0.328 +/- 0.264 and 0.022 +/- 0.026 for animals born in the same and in different herds, respectively. The computed genetic contributions to the reference population resulted in estimates for the effective number of founders, ancestors, founding herds, and herds supplying sires of 121.6, 55.0, 17.1, and 26.9, respectively, the 2 most influential herds and ancestors contributing 24.2 and 15.1%, respectively, of the current genetic pool. Of the 671 founding sires, only 24 Y-chromosomes are currently represented, but 1 sire alone contributes nearly 60% of this representation, such that the effective number of Y-chromosomes is only 2.73. The observed inbreeding per herd was, on average, 0.053 +/- 0.071 lower than expected from the relationship among the generation of parents of calves in the reference population, indicating that producers have followed breeding strategies that have kept inbreeding at lower levels than anticipated with random selection and mating. When compared with other cattle breeds, Alentejana has some of the highest levels of mean inbreeding and annual rate of inbreeding, and an effective population size that is nearly half of the minimum recommended for maintenance of genetic variability. These critical indicators demonstrate the need to adopt strategies aimed at minimizing inbreeding to avoid further losses of genetic diversity.  相似文献   

17.
The objective of this study was to determine the inbreeding levels and to analyze the pedigree of Irish purebred populations of Charolais, Limousin, Hereford, Angus, and Simmental beef cattle, as well as the Holstein-Friesian dairy breed. Pedigree analyses included quantifying the depth of known pedigree, average generation intervals, effective population size, the effective number of founders, ancestors, and founder genomes, as well as identifying the most influential animals within the current population of each breed. The annual rate of increase in inbreeding over the past decade was 0.13% (P < 0.001) in the Hereford, 0.06% (P < 0.001) in the Simmental, and 0.10% (P < 0.001) in the Holstein-Friesian breeds. Inbreeding in the other breeds remained relatively constant over the past decade. Herefords had the greatest mean inbreeding in 2004, at 2.19%, whereas Charolais had the lowest, at 0.54%. Over half of each purebred population in 2004 was inbred to some degree; the population with the greatest proportion of animals inbred was the Hereford breed (85%). All 6 breeds displayed a generation interval of approximately 6 yr in recent years. In the pure-bred females born in 2004, the 3 most influential animals contributed between 11% (Limousin) and 24% (Hereford) of the genes. Effective population size was estimated for the Hereford, Simmental, and Holstein-Friesian only, and was 64, 127, and 75, respectively. The effective number of founders varied from 55 (Simmental) to 357 (Charolais), whereas the effective number of ancestors varied from 35 (Simmental and Hereford) to 82 (Limousin). Thus, despite the majority of animals being inbred, the inbreeding level across breeds is low but rising at a slow rate in the Hereford, Simmental, and Holstein-Friesian.  相似文献   

18.
The most common goal of animal conservation programmes is to maintain genetic diversity. Various measures for genetic variability based on pedigree information can be used, but most of them are very sensitive to completeness of pedigree information. Different criteria based on probability of identity-by-descent (effective population size via increase in inbreeding Ne) or probability of gene origin (effective number of founders fe, ancestors fa and founder genomes Ng) were used to describe the genetic variability of three Austrian cattle breeds [Original Pinzgau (PI), Tux-Zillertal (TZ), Carinthian Blond (CB)]. Reference populations for PI were defined by animals born between 1993 and 1997 and for TZ and CB by all living animals, irrespective of birth year. The numbers of animals in the reference populations were 9706, 471 and 230 for PI, TZ and CB, respectively. The average complete generation equivalent showed the different quality of pedigree information: 5.33 for PI, 2.52 for TZ and 1.73 for CB. The following Nes were calculated: 76 for PI and CB and 43 for TZ. For PI, TZ and CB a fe-value of 65.4, 21.0 and 29.9, a fa-value of 32.1, 14.2 and 29.0 and a Ng-value of 19.5, 9.7 and 22.6, respectively, were calculated. In particular, the results for TZ demonstrate the urgent need for a well-planned conservation programme.  相似文献   

19.
Polish Arabian horses are a good example of a small population derived from a finite number of founders. Pedigree analysis showed significant reduction in the genetic diversity of the population. However, taking into account some circumstances suggesting the presence of balancing selection favouring heterozygotes in Polish breeding, it seems that this referred to pedigree uniformity rather than to a real decrease in genetic variability. The aim of the current study was to verify the hypothesis that balancing selection affects the population. The mare selection process was examined in detail regarding the polymorphism of 10 protein markers. The findings confirmed the tendency to favour the more heterozygous mares with regard to average heterozygosity in total and in relation to particular loci, studs, fathers and inbreeding ranges. The results were discussed in consideration of selection criteria, inbreeding level of Polish Arabs and heterozygosity in other populations.  相似文献   

20.
The aim of this analysis is to assess the genetic diversity in the black-coated Asturcón pony population using genealogical and molecular methods in order to ascertain the possible impact of the inclusion of the bay Asturcón individuals on the breed's recovery programme. Pedigree information registered in the studbook of the black-coated Asturcón (including a total of 1080 individuals) was analysed. Additionally, 261 blood samples from the black-coated Asturcón individuals were obtained and genotyped for 15 microsatellites. Furthermore, 58 blood samples were obtained and genotyped from bay Asturcón individuals in order to place the results within the context of an unselected population with no known genealogies. The results indicated high losses of genetic representation of founders in the present population of black-coated Asturcón ponies. Roughly 60% and 30% of the founder stallion and dam lines, respectively, are lost in the present population. Average inbreeding was 4.7%. The equivalent number of founders and equivalent number of ancestors were 18.1 and 13. The most relevant founders and ancestors identified belonged to the three major studs involved in the recovery of the breed. However, the results highlight the dependence of the breed on the management of the government-run Cayón stud, which has increased its genetic contribution to the breed over time from 35.6% to 50.1%. At a molecular level, genetic variability assessed in the black-coated Asturcón was lower than that observed in the bay Asturcón. Expected heterozygosity, FIS(m) and rarefacted average number of alleles per locus were 0.755 and 0.828, 4.1% and 1.3%, and 9.5 and 9.2, respectively, for the black-coated and bay Asturcón. The expected molecular coancestry in the black-coated Asturcón base population (Ef0) took a value of 0.229, which was near to the molecular coancestry computed in the bay Asturcón (0.231). Implications of the reported results in the recovery programme of the Asturcón pony breed are discussed.  相似文献   

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