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ORIGINAL PAPER THE RESULTS OF REPRODUCTION UTILITY OF THE POLISH PRIMITIVE HORSE IN THE CHOSEN STUD FARM IN POLAND IN THE PERIOD WYNIKI UŻYTKOWANIA ROZPŁODOWEGO KONIKA POLSKIEGO Z WYBRANEJ Z STADNINY KONI W POLSCE STANISŁAW KUBACKI, FELICJAN PIKULIK*, EWA MROZIK-GLISZCZYŃSKA, NATASZA ŚWIĘCICKA University of Technology and Life Science, Faculty of Animal Breeding and Biology, Departament of Horse Breeding and Fur Animals Mazowiecka 28, 85-084 Bydgoszcz, Poland Phone (+) 48 52 374 9704, fax (+) 48523228158, e-mail futerka@utp.edu.pl *The Horse Stud Farm Dobrzyniewo ABSTRACT The analysis of Polish Primitive Horse reproduction, in the stable breeding in Dobrzyniewo, was carried out in the period 1993/1994 2003/2004. On the basis of the carried out analysis it is evident systematic increase (positive trend) of basic coefficients of reproduction (foaling, fertility, fecundity, birth) and a decrease of coefficients of infertility and abortions. On the other hand leading sires were stallions: Mikrus and Jehol, which were utilised in reproduction for the period of 11 years while mares covered by these stallions had relatively high coefficients of reproduction. KEY WORDS: Polish Primitive Horse, coefficients of reproduction, tendencies STRESZCZENIE Analizę rozrodu konika polskiego z hodowli stajennej w Dobrzyniewie przeprowadzono za okres 1993/1994 2003/2004. Z przeprowadzonej analizy wynika systematyczny wzrost (trend dodatni) podstawowych wskaźników rozrodu (źrebności, płodności, plenności i wyźrebień), a spadek wskaźnika jałowienia i poronień. Z kolei czołowymi reproduktorami okazały się ogiery: Mikrus i Jehol, które były użytkowane rozpłodowo przez okres 11 lat, natomiast klacze kryte tymi ogierami charakteryzowały się stosunkowo wysokimi wskaźnikami rozrodu. SŁOWA KLUCZOWE: konik polski, wskaźniki rozrodu, tendencje. Volume 11 (2010) No. 2 (159-164) 159

STANISŁAW KUBACKI, FELICJAN PIKULIK*, EWA MROZIK-GLISZCZYŃSKA, NATASZA ŚWIĘCICKA DETAILED ABSTRACT Badaniami objęto 60 klaczy, 8 ogierów rasy konik polski użytkowanych rozpłodowo w stadninie Koni Dobrzyniewo w latach 1993/1994-2003/2004. Obliczono podstawowe wskaźniki rozrodu tj. wskaźnik źrebności, jałowienia, poronień, płodności, plenności (produkcyjności), odchowu i wyźrebień. Ponadto dokonano charakterystyki oceny użytkowości rozpłodowej 8 ogierów na podstawie wyliczonych wskaźników rozrodu klaczy. W badanym okresie zaobserwowano wyraźny postęp hodowli konika polskiego w SK Dobrzyniewo o czym świadczy systematyczny wzrost (trend dodatni) podstawowych wskaźników rozrodu (źrebności, płodności, plenności i wyźrebień), a spadek wskaźnika jałowienia i poronień. Czołowymi reproduktorami okazały się ogiery: Mikrus i Jehol, które były użytkowane przez okres 11 lat, a klacze kryte tymi ogierami charakteryzowały się stosunkowo wysokimi wskaźnikami rozrodu INTRODUCTION Polish Primitive Horses and Hucul Horses are counted to the Primitive breeds. Breeding of these races is carried on both in the studs [5] and reservation breeding [4,8,7]. The breeding of these races of horses is aiming at the preservation of genetic bio-diversity counteracting, at the same time, the increase of inbreeding coefficient which might come out because of the small number of population. It is visible particularly in the reservation breeding [3]. The purpose of stud breeding is also the preservation of the utility traits and at the same time carrying out the utility trials of these horse breeds [2]. The aim of work was the analysis of reproduction utility of Polish Primitive Horse from the stable breeding utilized in the Horse Stud Farm Dobrzyniewo in years 1993/1994-2003/2004. MATERIAL AND METHODS The research comprised 60 mares, 8 stallions of the Polish Primitive Horse utilized reproductively in the Horse Stud Farm Dobrzyniewo in years 1993/1994 2003/2004. The numerical data, concerning the reproduction traits, were taken from the files of Stud Farm Dobrzyniewo. The presented coefficients of reproduction of mares were calculated according to the following formulae: 1. the coefficient of pregnancy = the number of pregnant mares / the number of covered mares x 100% 2. the coefficient of sterility = the number of sterility mares / the number of covered mares x 100% 3. the coefficient of abortion = the number of abortion mares / the number of pregnant mares x 100% 4. the coefficient of fertility = the number of foals born alive / the number of covered mares x 100% 5. the coefficient of fecundity = the number of weaned foals / the number of covered mares x 100% 6. the coefficient of rearing = the number of reared foals / the number of foals born alive x 100% 7. the coefficient of foaling = the number of born foals / the number of mares in the herd x 100% The presented values of coefficients, describing the reproduction of mares were shown as a function of the first degree that is the straight trend line [9,11]. For the particular trend line the correlation coefficient was calculated r xy [10] assuming: x- the following years as an operand (an independent variable) y- the trend line as a dependent variable Moreover the characterization of reproduction utility of 8 stallions has been carried out on the basis of the calculated reproduction coefficients of mares utilized in the period 1993/1994 2003/2004. RESULTS AND DISCUSIONS The results concerning the tendencies of the calculated coefficients, describing the reproduction utility of Polish Primitive Horse mares, were presented in the table 1. In the investigated period of time an increase (positive trend) of foaling, fertility, fecundity and births coefficients was visible. Because of this the tendency line equation for the coefficient of foaling of mares utilized reproductively in these years had a value y = 81,02 + 1,39x and it proves constant increase of the coefficient on the average 1,39 individuals per year. A relative increase per year was 1,72%. The highest relative increase appeared in the coefficient of births of mares (3,68%) for which unanimously the mean increase per year was 2,37 individuals and the coefficient was statistically very significant (r xy = 0,67**). A positive phenomenon was noticed also in the decreasing tendency of infertility and miscarriage coefficients. The coefficient of infertility didn t appear at the end of the investigated period, and the coefficient of miscarriage, which at the beginning of the 90-ies was on the level of 13% in 2003/2004 was around 4-5% and it was higher than breeding of this race in other centers [1] and it was on the similar level in the stable breeding of Hucul breed utilized in the Horse Stud Farm Gładyszów in years 1993-2003 [6]. Only 160 Journal of Central European Agriculture Vol 11 (2010) No 2

THE RESULTS OF REPRODUCTION UTILITY OF THE POLISH PRIMITIVE HORSE IN THE CHOSEN STUD FARM IN POLAND IN THE PERIOD 1 Tabela1. Linia tendencji (trend) dotycz ca wska ników rozrodu klaczy konika polskiego w Stadninie Koni Dobrzyniewo w latach 1993/1994-2003/2004 Table 1. The tendency line (trend) concerning the coefficients of reproduction of mares of the Polish Primitive Horse Stud Farm Dobrzyniewo in years 1993/1994 2003/2004. Wska nik Rate of rebno ci pregnancy ja owienia 1 sterility poronienia abortion p odno ci fertility plenno ci fecundity odchowu rearing wy rebie foaling 1993/1994 2003/2004 Lata 1993/1994 2003/2004 Years 1993/1994 2003/2004 trend tendency n = 11 R 2 rxy Wzgl dny wzrost lub spadek The relative increase or decrease (%) 88,5 96,0 y = 81,02+1,39x 0,338 0,58 1,72 11,5 - y = 19,57-1,54x 0,220-0,47 8,05 13,0 4,2 - - - - 78,3 87,5 y = 83,06+0,98x 0,111 0,33 1,18 69,2 80,0 y = 67,28+1,83x 0,326 0,57 2,72 100,0 95,2 y = 101,32-0,45x 0,399-0,63** 0,44 69,2 84,0 y = 64,45+2,37x 0,449 0,67** 3,68 Trend obliczony za lata 1993/1994-1999/2000 The tendency line of 1993/1994-1999/2000 years J. Cent. Eur. Agric. (2010) 11:2, 159-164 161

STANISŁAW KUBACKI, FELICJAN PIKULIK*, EWA MROZIK-GLISZCZYŃSKA, NATASZA ŚWIĘCICKA Tabela 2. Charakterystyka u ytkowo ci rozp odowej ogierów na podstawie wska ników rozrodu klaczy w Stadnie Koni Dobrzyniewo w latach 1993/1994 2003/2004 Table 2. The characterization of reproduction utility of stallions on the basis of reproduction coefficients of mares in the Horse Stud Farm Dobrzyniewo in years 1993/1994 2003/2004. LU * / Wska niki rozrodu klaczy The mares birth vate odchowu rearing plenno ci fecundity p odno ci fertility poronie abortion ja owienia sterility rebno ci pregnancy Liczba pokrytych klaczy The number of covered mares Liczba lat u ytkowania ogiera The number of stallion Nazwa ogiera The name of a stallion Tr bacz 2 14 64,3 35,7 0 100,0 64,3 100,0 1,25 Mikrus 11 72 82,9 15,8 6,0 87,6 70,5 100,0 1,08 Jehol 11 74 89,0 11,0 4,1 87,6 76,7 98,5 0,78 Narcyz 1 6 100,0 0 0 100,0 100,0 100,0 0,50 Jaszczyk 3 19 89,7 10,3 0 88,9 78,6 100,0 0,67 Nobis 4 32 100,0 0 2,5 97,5 94,4 96,9 1,00 Komes 2 8 87,5 12,5 0 100,0 75,0 87,5 0,50 Noktus 1 6 100,0 0 0 100,0 100,0 100,0 1,00 * LU - stosunek liczby urodzonych rebi t (klaczy/ogierów)- the ratio of born foals (mares/stallions) the coefficient of rearing was decreased (95,2%) which for a few years was on the level of maximum (100%). However it is comparable to the Hucul breed of horses [6]. On the other hand the coefficient of fecundity, that is the ratio of weaned foals to the number of covered mares, as an indicator of the breeding success showed increasing tendency from year to year (y = 67,28 + 1,83 x). The coefficient is significant because it is the outcome between genetic and phenotype values of foals, the traits which were given by the parents and on the other hand the environmental conditions created by the breeder (buildings, fodder, supervision etc.). Other factors have an impact on the decrease of the number of weaned foals (fecundity). In the reservation there are often drownings, dwarfism, inborn traits [3]. On the other hand in the stable breeding there are deaths and putting to sleep because of the fate accidents. Quoting Balińska and Nowicka-Posłuszna [1] the coefficient of fertility for the Polish Primitive Horse in Kobylniki and Sieraków Stud Farm mean for the years 1984/1985 2002/2003 was respectively 72,7%; 79,3%. Table 2 presents the analysis of reproduction of 8 stallions on the basis of the reproduction of mares. The leading stallions, which were utilized reproductively for the longest period of time (11 years) were Mikrus and Jehol. Mares covered by these stallions in the number of 72, 74 were characterized by the relatively high coefficients of reproduction. We can say that the coefficients of reproduction of mares, which were obtained as a result of covering by Mikrus and Jehol, were similar to the coefficients obtained for the mares of Hucul breed which were covered by outstanding sires of this breed (eg. Jaśmin, Prislop IX 81, or Piaf) [6]. The ratio of gender ( / ) of progeny ranged from 0,5 to 1,25. CONCLUSIONS 1. During the investigated period (1993/1994 2003/2004) a significant progress was visible for breeding of Polish Primitive Horse in the Horse Stud Farm Dobrzyniewo. The progress is visible by the systematic increase of basic coefficients of reproduction that is foaling, fertility, fecundity, births coefficients and the decline of coefficients of infertility and miscarriage. 2. The leading sires were stallions: Mikrus and Jehol, which were utilized for 11 years. Mares covered by these sires had high coefficients of reproduction. REFERENCES [1]. Balińska K., Nowicka-Posłuszna A., Estimation of reproduction indices of mares of Konik Polski breed used in preservative breeding center in Wielkopolska. 162 Journal of Central European Agriculture Vol 11 (2010) No 2

THE RESULTS OF REPRODUCTION UTILITY OF THE POLISH PRIMITIVE HORSE IN THE CHOSEN STUD FARM IN POLAND IN THE PERIOD Science Journals PTZ. Breeding Journal (2004) 72 (5): 219-225 [in Polish]. [2]. Górecka A., Jaworski Z., Jezierski T., Golonko M., Preliminary analysis of the results of performance test in Konik Polski horses maintained as the genetic reserve. Science Journals PTZ. Breeding Journal (2003) 68 (5): 21-27 [in Polish]. [3]. Jaworski Z., The Polish Primitive Horse in a nature reserve evaluation of the ethologic and breeding conditions. Thesis for the degree of associate professor. University of Warmia and Mazury in Olsztyn (2003) [in Polish]. [4]. Jaworski Z., Golonko M., Territorialism of Konik Polski horses kept in the system of reservation. Science Journals PTZ. Breeding Journal (2003) 68 (5): 11-19 [in Polish]. [5]. Jezierski T., Jaworski Z., Polish Primitive Horses from Popielno. The institute of genetics and breeding of animals. Polish Academy of Sciences in Jastrzębiec. (1995) [in Polish]. [6]. Kubacki S., Kario W, Kubacki P., Grygiel A., The analysis of breeding performance of Hucul breed of horses in SK Gładyszów in years 1993-2003. Science Journals PTZ. Breeding Journal (2004) 72 (5): 211-217 [in Polish]. [7]. Łojek J., Górska B., Comparison of behavior of Konik Polski horses in two housing systems. LXXI Congress of PTZ in Bydgoszcz Academic articles (2006) 3, 18 [in Polish]. [8]. Małecka M., The behavior activity of Hucul breed horses kept in natural environment in the Horse Stud Farm Seredno. MS thesis (manuscript) the Academy of Technology and Agriculture. Bydgoszcz (2005) [in Polih]. [9]. Schmidt S. The implementation of statistical methods in animal Husbandry PWRiL, Warsaw (1964). [10]. Szulc S. Statistical methods, PWE, Warsaw (1968). [11]. Zając J. The outline of statistical methods. PWE, Warsaw (1971). J. Cent. Eur. Agric. (2010) 11:2, 159-164 163