Diversity of wild and domestic pig populations estimated by a set of serum allotypes

Variation of serum protein allotypes serving as genetic markers of the blood has been analyzed in 29 populations of the domestic pig and subspecies of the wild boar. The population biodiversity and genetic structure have been estimated by two methods: by the frequencies of allotype combinations and with the use of a map constructed in the space of two principal components. The results obtained are the basis for determining the characteristics of the microevolution of wild boars and formation of the breeds of domestic pigs.     

Electrophoretic variants of serum transferrin in wild pig populations of Japan

Variants of serum transferrin in Japanese wild pig, Sus scrofa leucomystax, and Ryukyu wild pig, S.s. riukiuanus, of Japan were investigated by using starch gel electrophoresis. Five phenotypes, TfB, BC, C, CX and X, were observed, of which two, TfCX and X, are new variants. Comparison of gene frequency estimates which were calculated for each population showed remarkable geographic differences among several populations of these two subspecies.     

Frequency of chromosomes carrying endogenous retroviruses in the populations of domestic pig and wild boar

Statistical analysis of the frequency of chromosomes carrying three types (A, B, and C) of porcine endogenous retroviruses (PERV) was based on molecular-genetic testing of populations of domestic pigs and wild boars. Domestic pigs were shown to have higher frequency of PERV and haplotypes containing two and three types of PERV than wild boars.     

Mitochondrial DNA sequence variation and phylogenetic relationships among Iberian pigs and other domestic and wild pig populations

Nucleotide sequences of mitochondrial DNA (mtDNA) cytochrome B gene (1140 bp) and control region (707 bp) were used to determine the phylogenetic relationships among 51 pig samples representing ancient and current varieties of Iberian pigs (26), Spanish wild boars (seven) and other domestic pigs (18) of cosmopolitan (Duroc, Large White, Landrace, Pietrain and Meishan) and local (Spotted Black Jabugo, Basque and Mangalitza) breeds. A neighbour-joining tree constructed from pairwise distances provide evidence of the European origin of both Iberian pigs and Spanish wild boars. The introgression of Asian mtDNA haplotypes in the genetic pool of the Iberian breed seems unlikely. Four estimates of sequence divergence between European and Asian clades were calculated from the two main domains of the D-loop region and the synonymous and nonsynonymous nucleotide substitutions in the cytochrome B gene. The time since the divergence of pig ancestors was estimated at about 600,000 years before present.     

Homology between the Lpm system of allotypes in the American mink and the Gp system of allotypes in the domestic pig]

The 5 alpha-macroglobulin allotypes alpha M1, alpha M2, alpha M3, alpha M4 and alpha M5 were identified in pig. The alpha M1 allotype was reported as a marker of pig alpha-macroglobulin, the latter being homologous to alpha 2-macroglobulins in human and in mink. The allotypes alpha M2-alpha M5 were specified as markers of the second isotypical variant of pig alpha-macroglobulins, which was homologous to mink Lpm macroglobulin (alpha 1M). As seen from data obtained by International Comparative Test ISABR 87-88, alpha M1 is a new allotype, while allotypes alpha M2--alpha M5 correspond to four allotypes in the Gp system (Janik et al.). Based on these data, a conclusion was made on the homology between the Lpm system in american mink and the Gp system in pig. Since the allotypes studied are the part of alpha-macroglobulins, a locus controlling them was designated the AM locus. We also find it more advantageous to apply the same name to the homologous locus in mink, instead of the Lpm used earlier. Genetic control of 5 allotypes was studied and the structure of the AM locus in pig analysed in detail. Comparative study of organization of the above locus and the homologous locus in mink was carried out.     

PGD variants in several wild pig populations of East Asia

PGD (6-phosphogluconate dehydrogenase) gene frequencies were reported in wild pigs, Sus scrofa, of three subspecies, i.e. Japanese wild pig, S.s. leucomystax, Ryukyu wild pig, S.s. riukiuanus, and Formosan wild pig, S.s. taivanus. Five phenotypes (A, AB, B, AC' and C') were observed. The C' variant was found only in the S.s. leucomystax, and may be identical to PGD-C reported by Archibald & McTeir (1988). PGD-A was a common variant in all the species in the genus Sus including wild pig, Sus scrofa, Javan pig, Sus verrucosus, and Bearded pig, Sus barbatus, and predominated in the whole populations examined except some of those of the S.s. riukiuanus. This suggested that the PGDA appeared before the other two alleles (B and C') during the evolution of the genus Sus.     

Chromosome R-banding patterns and NOR homologies in the European wild pig and four breeds of domestic pig

Four European wild pigs and 27 domestic pigs were studied; three Landrace, 12 village pigs from Papua New Guinea, two Chinese pigs Meishan and 10 Creole pigs from the French Antilles. The R-banding patterns were identical for all domestic breeds despite their different history and geographical divergence. The European wild pigs showed a similar R-banding pattern and a centric fusion between pairs 15 and 17 (2n = 36). The nucleolar organizers (NORs) in the European wild pig and the four domestic breeds were localized on the secondary constriction of chromosomes 8 and 10. All animals exhibited in the majority of metaphases two NORs on both chromosomes 10. In some animals. the NORs were expressed only in one of the homologs of chromosome 8. The Chinese pigs had a high amount of silver precipitates on two homologs of chromosome 8. This study confirms several previous reports on the polymorphism of NOR patterns in different domestic pig breeds.     

Maintaining genetic integrity of coexisting wild and domestic populations: Genetic differentiation between wild and domestic Rangifer with long traditions of intentional interbreeding

This study investigates the genetic effect of an indigenous tradition of deliberate and controlled interbreeding between wild and domestic Rangifer . The results are interpreted in the context of conservation concerns and debates on the origin of domestic animals. The study is located in Northeastern Zaba?kal'e, Russia at approximately 57 degrees North latitude. Blood and skin samples, collected from wild and domestic Rangifer , are analyzed for their mtDNA and microsatellite signatures. Local husbandry traditions are documented ethnographically. The genetic data are analyzed with special reference to indigenous understandings of the distinctions between local domestic types and wild Rangifer . The genetic results demonstrate a strong differentiation between wild and domestic populations. Notably low levels of mtDNA haplotype sharing between wild and domestic reindeer, suggest mainly male‐mediated gene flow between the two gene pools. The nuclear microsatellite results also point to distinct differences between regional domestic clusters. Our results indicate that the Evenki herders have an effective breeding technique which, while mixing pedigrees in the short term, guards against wholesale introgression between wild and domestic populations over the long term. They support a model of domestication where wild males and domestic females are selectively interbred, without hybridizing the two populations. Our conclusions inform a debate on the origins of domestication by documenting a situation where both wild and domestic types are in constant interaction. The study further informs a debate in conservation biology by demonstrating that certain types of controlled introgression between wild and domestic types need not reduce genetic diversity.     

Novel Y‐chromosome short tandem repeats in Sus scrofa and their variation in European wild boar and domestic pig populations

Y‐chromosome markers are important tools for studying male‐specific gene flow within and between populations, hybridization patterns and kinship. However, their use in non‐human mammals is often hampered by the lack of Y‐specific polymorphic markers. We identified new male‐specific short tandem repeats (STRs) in Sus scrofa using the available genome sequence. We selected four polymorphic loci (5–10 alleles per locus), falling in one duplicated and two single‐copy regions. A total of 32 haplotypes were found by screening 211 individuals from eight wild boar populations across Europe and five domestic pig populations. European wild boar were characterized by significantly higher levels of haplotype diversity compared to European domestic pigs (H_D = 0.904 ± 0.011 and H_D = 0.491 ± 0.077 respectively). Relationships among STR haplotypes were investigated by combining them with single nucleotide polymorphisms at two linked genes (AMELY and UTY) in a network analysis. A differentiation between wild and domestic populations was observed (F_ST = 0.229), with commercial breeds sharing no Y haplotype with the sampled wild boar. Similarly, a certain degree of geographic differentiation was observed across Europe, with a number of local private haplotypes and high diversity in northern populations. The described Y‐chromosome markers can be useful to track male inheritance and gene flow in wild and domestic populations, promising to provide insights into evolutionary and population genetics in Sus scrofa.     

Reduction of flobufen in pig hepatocytes: effect of pig breed (domestic,wild) and castration

Knowledge of the biotransformation processes of veterinary drugs and food supplements in food-producing animals is increasingly important. Residual levels of parent compounds or their metabolites in food of animal origin may differ with the breed, breeding conditions, and gender of animals. The nonsteroidal antiinflammatory drug flobufen, 4-(2',4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid (racemic or its individual enantiomers) was used as a model to evaluate differences in activity, stereoselectivity, and stereospecificity of reductases in primary cultures of hepatocytes from intact male or castrated male domestic pigs (Sus scrofa domestica) or male wild pig (Sus scrofa scrofa). Time-dependent consumption of flobufen enantiomers and formation of dihydroflobufen (DHF) diastereoisomers as their principal metabolites in hepatocytes were measured using chiral HPLC. Flobufen reduction in hepatocytes from all three experimental groups of animals was stereoselective ((+)-R-flobufen was predominantly metabolized) and stereospecific (2R;4S-DHF and 2S;4S-DHF diastereoisomers were preferentially formed). Flobufen reductases activity in male domestic pigs was 30 times higher compared to castrated pigs. Flobufen reductases activity was similar in domestic and wild pigs. The stereospecificity and stereoselectivity of DHF production did not significantly differ with breed or castration of animal. Chiral inversion of flobufen enantiomers was also studied and differences between castrated and intact male pigs were seen.     

A2G--a new system of alpha-2-globulin allotypes in pig blood serum]

Combinations of four alpha-2-globulin allotypes were studied for their distribution in pigs of nine different breeds and hybrid groups. Based on this analysis, a new, previously unpublished polyallelic genetic system designated A2G was postulated. The complex alleles of this system control alpha-2-globulin allotypes and are suggested to be encoded by genes of two subloci. One of these subloci is virtually monomorphic, whereas the other has at least four allelic variants.     

Structure traits of Longissimus lumborum muscle in wild boar/domestic pig hybrids

The structure of musculus longissimus lumborum (m.l.l.) was evaluated with respect to proportion of three muscle fiber types and their diameters, in gilts and barrows of wild boar/domestic pig hybrids. The experiment was carried out on 29 hybrids (21 barrows and 8 gilts) which originated from crossing Duroc sows with wild boar (Sus scrofa ferus). The diameter of the "red" fibres in barrows was 48.42 microm, significantly greater than in gilts--43.71 microm. The diameters of the remaining two types of fibres in barrows and gilts were similar and amounted to: "intermediate" fibres--39.08 and 40.79 microm, "white" fibres--51.42 and 51.03, respectively. In respect to sex no statistical differences in proportion of any types of fibers were found, which in barrows came to: "red"--12.93%, "intermediate"--30.17% and "white"--57.32%, and in gilts to: 12.50, 27.04 and 60.45%, respectively. In conclusion, in m.l.l. of wild boar/domestic pig hybrids, smaller diameters of all muscle fibers types were identified as well as a higher proportion of intermediate fibers in comparison to m.l.l. of various pig breeds. An increased proportion of the intermediate fibers probably results from the interaction between factors such as age (8-months), physical activity (open-air for running) and the influence of wild boar genes.     

Intra-population comparison of vegetative and floral trait heritabilities estimated from molecular markers in wild Aquilegia populations

Measuring heritable genetic variation is important for understanding patterns of trait evolution in wild populations, and yet studies of quantitative genetic parameters estimated directly in the field are limited by logistic constraints, such as the difficulties of inferring relatedness among individuals in the wild. Marker-based approaches have received attention because they can potentially be applied directly to wild populations. For long-lived, self-compatible plant species where pedigrees are inadequate, the regression-based method proposed by Ritland has the appeal of estimating heritabilities from marker-based estimates of relatedness. The method has been difficult to implement in some plant populations, however, because it requires significant variance in relatedness across the population. Here, we show that the method can be readily applied to compare the ability of different traits to respond to selection, within populations. For several taxa of the perennial herb genus Aquilegia, we estimated heritabilities of floral and vegetative traits and, combined with estimates of natural selection, compared the ability to respond to selection of both types of traits under current conditions. The intra-population comparisons showed that vegetative traits have a higher potential for evolution, because although they are as heritable as floral traits, selection on them is stronger. These patterns of potential evolution are consistent with macroevolutionary trends in the European lineage of the genus.     

Gm allotypes and racial admixture in two Brazilian populations

Summary The Gm types of 515 inhabitants of Belém and 395 inhabitants of Porto Alegre, Brazil were studied in an attempt to quantitatively estimate ethnic parental contributions. The people from Belém can be characterized as 24% black, 22% Indian, and 54% Caucasian. The Porto Alegre blacks seem to have inherited as much as 53% of their genes from Caucasian ancestors, while the whites living there have inherited 8% of their genes from African ancestors. The admixture values obtained for Belém are very similar if just the Gm system is considered or it plus seven other loci are considered, emphasizing the high efficiency of the Gm markers in such analyses.     

Serologic evidence of Venezuelan equine encephalitis in some wild and domestic populations of southern Texas.

More than 2,500 sera from approximately 30 wild and domestic species in southern Texas were tested for neutralizing antibodies to Venezuelan equine encephalitis (VEE). Virus isolations were also attempted from blood and tissue samples of many of the wild specimens. VEE neutralizing substances were present in a variety of species collected prior to the 1971 epizootic, suggesting that VEE was present and perhaps enzootic in this area before the recent epizootic. Serologic results of this study suggest that deer (Odocoileus virginianus) and feral swine (Sus scrofa) may serve as good indicators or sentinels of VEE transmission. The reservoir of VEE was not established, but results of the study suggest that a number of species or a combination of animal host populations including deer, feral swine, and peccaries (Pecari angulatus) may be involved in the eizootiologyof VEE in southern Texas.     

Determination of human IgI allotypes by using a set of stable erythrocyte antigenic diagnostica of varying specificity]

Technology of preparing a set of stable antigenic diagnostic agents of commercial type for determination of genetic determinants of human IgG and antibodies to them in the human blood sera and in the animal hyperimmune sera was worked out. Antisera against some human IgG allotypes were prepared. The frequency of detection of individual IgG allotypes and antibodies to them in human sera was studied.     

Distribution of Gm and Km allotypes among five populations in China

Serum samples from five populations in China [173 from Huhehote (Naimengu Zhizhiqu), 195 from the Beijing area, 131 from Hefei (Anhui Province), 155 from Hangzhou (Zhejiang Province), and 152 from Guangzhou (Guangdong Province)] were tested for G1m(1, 2, 3, and 17), G2m(23), G3m(5, 10, 11, 13, 14, 15, 16, 21, and 26), and Km(1). The Gm pattern of the Chinese populations are characterized by the presence of four haplotypes, Gm1, 17;..;21, 26, Gm1, 2, 17;..;21, 26, Gm1, 17;..;10, 11, 13, 15, 16, and Gm1, 3;23;5, 10, 11, 13, 14, 26, which are characteristic of Mongoloid populations. Agreement was obtained in all Chinese samples between the observed and expected frequencies on the basis of the Hardy-Weinberg equilibrium of phenotypes. Heterogeneity tests of the haplotypic distributions among the five populations showed no significant differences in the distributions of Gm phenotypes between Huhehote and Beijing nor between Hefei and Hangzhou, whereas highly significant differences were observed among the three districts: northern part (Huhehote and Beijing), central part (Hefei and Hangzhou), and southern part (Guangzhou). The data indicate a south to north genocline, ranging from Huhehote to Guangzhou in which Gm1, 17;..;21, 26 changes from 0.471 to 0.183, Gm1, 17;..;10, 11, 13, 15, 16 from 0.097 to 0.033, and Gm1, 3;23;5, 10, 11, 13, 14, 26 from 0.229 to 0.730. In contrast to the Gm system, no significant regional differences in the frequencies of the Km1 allele were observed among the five populations.