Сельскохозяйственная биология, 2011, № 6, с. 37-40

УДК 636.2:575.174.015.3

THE COMPARATIVE ANALYSIS OF BLOOD GROUPS AND MICROSATELLITES IN CHARACTERISTICS OF NEW CATTLE TYPES OF BROWN SWISS AND SYCHEVSKAJA BREEDS

P.V. Gorelov¹, D.N. Kol’tsov², N.A. Zinovieva¹, E.A. Gladyr’¹

The allele pool of new cattle types of Brown Swiss and Sychevskaja breeds using two types of genetic markers (blood groups and microsatellites) was studied. It was shown that the combined application of both marker types provides with more complete data about population statement and structure.

Keywords: blood group systems, microsatellites, genetic diversity, cattle breeds.

Today, the allele pool of various breeds and populations of farm animals can be characterized using genetic markers of different types. In cattle, there are two most widespread types of markers – erythrocyte antigens of blood groups and microsatellites (1, 2). Genetic markers allow to estimate in animals the degree of heterozygosity, the level of consolidation of hereditary properties of breeds, types, lines and genetic differences between them. However, markers of different types provide detection of significantly different population-genetic parameters (3). Therefore, the data obtained through this technique should be analyzed considering peculiarities of the applied marker systems.
In the Smolensk province, two new types of cattle - Smolensk type of Browin Swiss (2003) and Vazuzsky type of Sychevskaya breed (2008). It has been reported about their allele pool assessed at the use of both erythrocyte antigens (4, 5) and microsatellites (6), but no comparative and comprehensive researches involving these both types of markers has been performed yet.
The purpose of this work was studying the population-genetic parameters of these new cattle types upon the data calculated from results obtained at the use of two marker systems - blood groups and microsatellites.
Technique. The material for a study were samples of blood and tissue (ear notches) obtained from cattle belonging to Smolensky type of Brown Swiss breed (n = 123) and Vazuzsky type of Sychevskaya breed (n = 67).
Blood groups of 8 genetic systems (A, B, F-V, J, L, M, S, Z) were determined in hemolytic tests at common techniques using monospecific reagents produced by Smolensk Research and Development Institute of Agriculture.
DNA extraction was performed using the columns by “Nexttec” (Germany) and the reagent kit DiatomTM DNA Prep100 (“Laboratory Isogene”, Russia). Microsatellites were analyzed on DNA analyzer ABI3130xl (“Applied Biosystems”, USA) according to techniques proposed by the Center of Biotechnology and Molecular Diagnostics of the All-Russia Research and Development Institute of Animal Husbandry. The set of markers for analysis included the following loci: TGLA126, TGLA122, TGLA227, INRA023, ILST005, ILST006, ETH185, ETH10, ETH225, BM1818, BM1824, BM2113, SPS115.
Statistical processing of data was carried out according to standard methods (7) in GenAlEx software (version 6.4). The validation of individual’s belonging to a particular breed according to J.K. Pritchard et al. (8) was performed using the software Structure (ver. 2.3.1). The analysis was conducted at non-specified prior data on individual’s belonging to a breed while considering the most probable number of populations (k = 2) at the level of exclusion (Q criterion) equal to 75%.
Results. The study of the analyzed sample group of cattle revealed the presence of 74 alleles belonging to 8 systems of blood groups and 106 alleles of 13 microsatellite loci, that averaged to,  respectively, 9,25 ± 2,20 and 8,15 ± 0,27 alleles per locus. The great diversity of blood groups can be explained by presence in EAB-locus of alleles specific to each cattle type – this fact was confirmed by presence of private alleles: 28 in Smolensky type of Brown Swiss (including 27 in the locus EAB ) and 23 in Vazuzsky type of Sychevskaya breed (including 22 in EAB locus). Respectively, 15 and 10 private alleles were identified in microsatellite loci of the studied cattle types. Smolensky type of cattle showed higher diversity of both blood groups and microsatellites than Vazuzsky type. However, microsatellite loci were found to contain more effective alleles (providing maximum contribution into the calculated degree of heterozygosity), which indicates a more uniform distribution of microsatellite alleles in the population compared to blood groups (Table 1).

Comparative evaluation of heterozygosity level in these populations calculated using two marker systems revealed significantly lower observed and expected absolute values for blood groups than for microsatellites. At the same time, the studied cattle types showed the excess of heterozygotes for blood groups (fixation index Fis equal to, respectively, -0,042 and -0,297) and, on the contrary, the lack of heterozygotes for microsatellites (Fis, respectively 0,037 and 0,029) (Table 2). Apparently, these findings can be explained by the fact that some alleles of blood groups are associated with productivity characteristics, while microsatellites are generally neutral in terms of selection.
The calculated fixation index Fst showed that 97,5% of all diversity for blood groups was provided by interbreed differences and 2,5% were interbreed differences; for microsatellite markers, the corresponding values equaled to 97,8 and 2,2%.
Average value of Q criterion indicates the degree of individual’s membership in the population; in Smolensky type of Brown Swiss cattle, this parameter for blood groups was 0,879 ± 0,014, for microsatellite markers - 0,849 ± 0,017 and for both types of markers - 0,948 ± 0,012. In Vazuzsky type of Sychevskaya breed, these parameters were, respectively, 0,900 ± 0,021; 0,897 ± 0,017 and 0,967 ± 0,014. The analysis of animals’ polymorphism for blood groups have shown that 90,2% of Smolensky cattle and 88,1% of Vazuzsky type were genetically identical to their breeds (Q> 75%); for microsatellites, these values amounted to, respectively, 80,5 and 89,6%, while the evaluation considering both types of markers provided higher results -  94,3 and 98,5% resp. Therefore, the combined use of two systems of allelic profiles increases the accuracy of evaluating breed identity of animals. The comparison of Q criterion values calculated for blood groups and microsatellites revealed relatively low positive correlation coefficient: r = +0,22 and r = +0,25, respectively, in Smolensky and Vazuzsky cattle. Apparently, these cattle types had been bred considering genotypes for blood groups, but microsatellites had been out of breeder’s attention.
Thus, the obtained results on polymorphism of blood groups and microsatellites in two new types of Brown Swiss and Sychevskaya cattle breeds suggest the joint use of both types of genetic markers for obtaining more complete data on animals’ population status and structure.

REFERENCES

1. Bukharov N.G., Khrunova A.I., Novikov A.A., Mishina N.S. and Politkin D.Yu., Evaluation of Bulls-Sires for Genetic Markers of Blood Groups, Zootekhniya, 2010, no. 11, pp. 2-3.
2. Zinovyeva N.A., Strekozov N.I. and Molofeeva L.A., Assessment of Role of DNA-Microsatellites in Genetic Characterization of Black-and-White Cattle Population, Zootekhniya, 2009, no. 1, pp. 2-4.
3. Proskurina N.V., Tikhomirova T.I., Gladyr’ E.A., Larionova P.V. and Zinovyeva N.A., Comparative Analysis of Informativeness of Erythrocytes Antigens and DNA-Microsatellites as Genetic Markers in Breeding-Pedigree Work with Pigs of Canadian Selection, S.-kh. biol., no. 6, pp. 41-47.
4. Gontov M.E., Kol’tsov D.N., Chernushenko V.K. and Dmitrieva V.I., Immunogenetic Monitoring in the Selection and Improving of “Smolensky” Type of Brown Swiss Cattle in Smolenskaya Oblast’, Dostizheniya nauki i tekhniki APK, 2011, no. 3, pp. 54-55.
5. Kol’tsov D.N., Chernushenko V.K., Romanov Yu.D. and Gontov M.E., Monitoring of Allelic Pool for Blood Groups in the Selection and Creation of New Type of Sychevskaya Cattle,  Dostizheniya nauki i tekhniki APK, no. 3, pp. 56-58.
6. Strekozov N.I., Zinovyeva N.A., Gorelov P.V., Listratenkova V.I., Konovalova E.N., Chernushenko V.K. and Ernst L.K., Genetic Characterization of New Cattle Types of Brown Swiss and Sychevskaya Breeds Using Polymorphism of Microsatellites, S.-kh. biol., 2009, no. 2, pp. 10-15.
7. Weir B., Analiz geneticheskikh dannykh (Genetic Data Analysis), Moscow, 1995.
8. Pritchard J.K., Stephens M. and Donnelly P., Inference of Population Structure Using Multilocus Genotype Data, Genetics, 2000, vol. 155, pp. 945-959.