Advisory Council. Statistics Editor Wilhelm Grzesiak. Lingual Editor Krystyna Kaźmierowska. Cover design Daniel Morzyński

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1 12 (4) 2013

2 Advisory Council Józef Bieniek (Kraków, Poland), Wiesław Nagórko (Warszawa, Poland), Janusz Prusiński (Bydgoszcz, Poland), Ewa Sobecka (Szczecin, Poland), Jerzy Sobota (Wrocław, Poland) Chairman, Stanisław Socha (Siedlce, Poland), Krzysztof Szkucik (Lublin, Poland), Waldemar Uchman (Poznań, Poland) Ryszard Źróbek (Olsztyn, Poland), Zootechnica (Animal Husbandry) Scientific Board Barbara Biesiada-Drzazga (Siedlce, Poland), Daniel Biro (Nitra, Slovakia), Maria Čechowa (Brno, The Czech Republic), Vincent Y-H Cheng (Tajwan), Janusz Falkowski (Olsztyn, Poland), Henryk Grodzki (Warszawa, Poland), Grażyna Jeżewska (Lublin, Poland), Valentin Katsarov (Stara Zagora, Bulgaria), Gabriel Kováč (Košice, Slovakia), Wojciech Kruszyński (Wrocław, Poland), André Mazur (Theix, France), Jan Mikołajczak (Bydgoszcz, Poland), Jerzy Niedziółka (Kraków, Poland), Stefan Pierzynowski (Lund, Sweden), Piotr Sablik (Szczecin, Poland) Chairman, Zbigniew Sobek (Poznań, Poland), Anke Romer (Dummerstorf, Germany), Stach Vovk (Lviv, Ukraine), Arda Yildirim (Tokat, Turkey) Statistics Editor Wilhelm Grzesiak Lingual Editor Krystyna Kaźmierowska Cover design Daniel Morzyński ISSN e-issn Copyright by Publishing House of West Pomeranian University of Technology, Szczecin 2013 Editor-in-Chief Piotr Sablik Doktora Judyma 10, Szczecin, tel Stock 60 copies, Print volume 5.10 Polish Standard Quires

3 Prof. dr hab. Aleksandra Balicka-Ramisz (Szczecin) Prof. dr hab. Wiesław Barabasz (Kraków) Prof. dr hab. Hanna Bis-Wencel (Lublin) Prof. dr hab. Danuta Borkowska (Zamość) Prof. dr hab. Teresa Bombik (Siedlce) Prof. dr hab. Marian Brzozowski (Warszawa) Prof. dr. hab. Janusz Falkowski (Olsztyn) Prof. dr hab. Andrzej Gugołek (Olsztyn) Prof. dr hab. Grażyna Jeżewska-Witkowska (Lublin) Prof. dr hab. Valentin Katsarov (Bułgaria) Prof. dr hab. Barbara Klocek (Siedlce) Prof. dr hab. Helena Kontecka (Poznań) Prof. dr hab. Maria Kulisa (Kraków) Prof. dr hab. Stanisław Kubacki (Bydgoszcz) Prof. dr hab. Jan Mikołajczak (Bydgoszcz) Prof. dr hab. Janina Pogorzelska (Olsztyn) Prof. dr hab. Piotr Przysiecki (Leszno) Prof. dr hab. Anna Rekiel (Warszawa) Prof. dr hab. Anna Sawa (Bydgoszcz) Prof. dr. hab. Stanisław Socha (Siedlce) Prof. dr hab. Anna Stachurska (Lubiln) Prof. dr hab. Zofia Tarasewicz (Szczecin) Prof. dr hab. Jerzy Wójcik (Szczecin) Dr hab. Marek Babicz, prof. nadzw. (Lublin) Dr hab. Maria Bogdzińska, prof. nadzw. (Bydgoszcz) Dr hab. Ewa Dzika, prof. nadzw. (Olsztyn) Dr hab. Dariusz Kokoszyński, prof. nadzw. (Bydgoszcz) Dr hab. Zenon Nogalski, prof. nadzw. (Olsztyn) Dr hab. Bożena Szejniuk, prof. nadzw. (Bydgoszcz) Dr hab. Brygida Ślaska, prof. nadzw. (Lublin) Dr hab. Bartłomiej Bartyzel (Warszawa) Dr hab. Angelika Cieśla (Szczecin) Dr hab. Wojciech Kruszyński (Wrocław) Dr hab. Danuta Majewska (Szczecin) Dr hab. Wanda Milewska (Olsztyn) Dr hab. Paweł Nawrotek (Szczecin) Dr hab. Arkadiusz Pietruszka (Szczecin) Dr hab. Bogumiła Pilarczyk (Szczecin) Dr hab. Piotr Sablik (Szczecin) Dr n. wet. Michał Skibniewski (Warszawa) Składam serdeczne podziękowania za wykonanie recenzji publikacji zgłoszonych w 2013 roku do Acta Scientiarum Polonorum Zootechnica Redaktor Acta Scientiarum Polonorum Zootechnica

4 Acta Sci. Pol., Zootechnica 12 (4) 2013, 5 16 CORRELATION OF THE TRAITS OF FUR FROM DIFFERENT PARTS OF THE BODY IN ARCTIC FOXES (ALOPEX LAGOPUS L.) Ryszard Cholewa 1, Jerzy Gedymin 1, Stanisław Socha 2 1 Poznań University of Life Sciences, Poland 2 Siedlce University of Natural Sciences and Humanities, Poland Abstract. The aim of the study was to investigate into the possibility of evaluating arctic fox fur basing on the correlation of laboratory measurements of hairs collected from various parts of the coat. The material involved samples of prime fur hairs of 20 two-year-old females of the blue arctic fox, collected at the end of January. The samples were cut by the skin at six places of the body, namely: the head (between the ears), back (in the middle between the tail base and the neck base), the side (below the place of sampling located on the back), belly (mid between the base of the front limbs and the vulva), the tail (in the middle of the dorsal side), as well as the shank. The samples were subjected to macro- and microscopic measurements. The results indicate that fur coat of arctic foxes is more dense, longer, and usually more intensely colored on the back, as compared to the belly. The hairs on the head and the limbs are much shorter and contain more awn hairs. The results reveal a very weak correlation of the morphological fur characteristics between different parts of the body. It has been found that it is impossible to objectively evaluate the basic structural characteristics and the dark tops of hairs in the arctic fox on the basis of a sample of hair from a single part of the body. Key words: arctic fox, hair coat, structural and morphological characteristics of hairs, variability INTRODUCTION Evaluation of a fur-bearer pelt is based on sensory rating of the characteristics, i.e. by sight and touch. Despite a high selectivity of human senses, it is merely Corresponding author Adres do korespondencji: prof. dr hab. Ryszard Cholewa, Poznań University of Life Sciences, Department of Small Mammals Breeding and Animal Origin Materials, Słoneczna 1, Suchy Las, Złotniki, Poland, cholewa@jay.up.poznan.pl

5 6 R. Cholewa et al. a subjective method. Measurements have so far involved only the size (length) of the pelt and the color of the fur. A more objective assessment of the individual characteristics of the structure and color of the coat, through measurements, is also possible [Gedymin et al. 1973, Cholewa, Gedymin 1974], which however is combined with taking samples of hair and can lead to a damage of the fur. Not all areas of the pelt are of equal value in terms of furriery; for example, the fur of the arctic fox on the head, legs, and belly is far less valuable than that on the sides, back, neck, thighs, or even on the tail. A minor damage resulting from hair sample collections from the peripheral parts of the body should not exert a major impact on the overall value of the pelt. In the case of a strong association (correlation) between the characteristics of the fur located on the peripheral regions and of that located on the most valuable parts of the pelt, the sensory evaluation could be supplemented by measuring the samples, thus carried out in an objective way. Applying such a method of assessment would primarily have a cognitive importance, showing the harmony of fur structure as a basis of the coat of an animal; it should also provide information for selection-purposes assessment a live fox, when the evaluation is much more difficult than in the case of a raw pelt. The aim of the study was to get an insight into the feasibility of arctic fox coat evaluation based on the correlation between laboratory measurements of hair samples collected from various parts of the body. MATERIAL AND METHODS The material was represented by samples of prime hair coat collected at the end of January from 20 two-year-old females of blue arctic foxes. The samples, cut by the skin with scissors, were collected from the following six places of the body: 1. Head (between ears), 2. Back (mid between tail base and neck base), 3. Side (below the place of the back sample collection), 4. Belly (mid between the base of frontal legs and the vulva), 5. Tail (middle of the dorsal side), 6. Shank (middle of the external side). The samples were subjected to macro- and microscopic measurements, which led to specifying the following characteristics: 1. Length of the hair (after straightening), 2. Height of the hair (distance between the apex and the base, measured in hair s natural state), 3. Length of the apical dark band, Acta Sci. Pol.

6 Correlation of the traits of fur in arctic foxes Thickness of the hair in its middle, 5. Thickness of the hair core in its middle, 6. Percentage composition of four hair types (guard, awn, transitional, and down hairs). The length of the hairs and color bands were measured using a ruler with precision to 1 mm, whereas the thickness of the hair and its core was measured under a microscope (VEB Carl Zeiss) with precision to 1.8 µm. The above-listed measurements allowed calculating the following indices: 1. Height-to-length ratio of the hair (%), describing hair undulation and corrugation, 2. The ratio of dark band length to the length of the hair (%), a characteristic of the so called voile, 3. The ratio of the core thickness to the hair thickness (%), 4. The ratio of the thickness in microns of the hair to its length in mm (coefficient of hair softness). All above-listed properties were measured and calculated for each of the four hair types, which had been distinguished in relation to structure and shape according to Toldt [1935]. These four types of hairs are: down, transitional, awn, and guard hairs. The arithmetic means were used to estimate correlations between individual places using the graphical methods with correlation grids. The dependences visible on the grid were ranked from 0 to 3 points, which has the following meaning: 0 no correlation (r) 1 r r r A minus sign ( ) was added to negative values. The correlation was estimated for 552 juxtapositions of paired parts of the body. RESULTS Arithmetic means of the characteristics listed in the previous section are presented in Table 1. Length. The longest coat hairs, i.e. guard and awn hairs, were found on the side, whereas the hairs of the underfur, transitional and down hairs, were roughly equal on the side and tail, although longer than those found on the other parts of the body. The shortest hairs of all four types were found on the peripheral parts, i.e. on the head and the shank; only down hairs were of similar length on the belly. Zootechnica 12 (4) 2013

7 8 R. Cholewa et al. Table 1. Arctic fox coat characteristics ( x, SD) Tabela 1. Cechy okrywy włosowej lisa polarnego ( x, SD) Characteristic Cecha 1. Length, mm Długość, mm 2. Height, mm Wysokość, mm 3. Height-to-length ratio, % Wysokość w % długości 4. Color band length, mm Długość pasa barwnego, mm 5. Color band length to hair length, % Długość pasa barwnego w % długości włosa 6. Hair thickness, μm Grubość włosa, μm 7. Core thickness, μm Grubość rdzenia, μm 8. Core thickness to hair thickness, % Grubość rdzenia w % gruości włosa, μm 9. Softness coefficient Współczynnik miękkości 10. Percentage contribution to sample, % Udział w próbce, % 1. Length, mm Długość, mm 2. Height, mm Wysokość, mm 3. Height-to-length ratio, % Wysokość w % długości 4. Color band length, mm Długość pasa barwnego, mm 5. Color band length to hair length, % Długość pasa barwnego w % długości włosa 6. Hair thickness, μm Grubość włosa, μm 7. Core thickness, μm Grubość rdzenia, μm Place of sample collection Miejsce pobrania próbek Head Ciemię Back Grzbiet Side Bok Belly Brzuch Tail Ogon Shank Podbudzie x SD x SD x SD x SD x SD x SD Guard hairs Włosy przewodnie Awn hairs Włosy ościste Acta Sci. Pol.

8 Correlation of the traits of fur in arctic foxes... 9 Table 1. Arctic fox coat characteristics ( x, SD) continued Tabela 1. Cechy okrywy włosowej lisa polarnego ( x, SD) ciąg dalszy Characteristic Cecha 8. Core thickness to hair thickness, % Grubość rdzenia w % grubości włosa, μm 9. Softness coefficient Współczynnik miękkości 10. Percentage contribution to sample, % Udział w próbce, % Place of sample collection Miejsce pobrania próbek Head Ciemię Back Grzbiet Side Bok Belly Brzuch Tail Ogon Shank Podbudzie x SD x SD x SD x SD x SD x SD Transitional hairs Włosy przejściowe 1. Length, mm Długość, mm Height, mm Wysokość, mm Height-to-length ratio, % Wysokość w % długości Color band length, mm Długość pasa barwnego, mm Color band length to hair length, % Długość pasa barwnego w % długości włosa 6. Hair thickness, μm Grubość włosa, μm Core thickness, μm Grubość rdzenia, μm Core thickness to hair thickness, % Grubość rdzenia w % grubości włosa, μm 9. Softness coefficient Współczynnik miękkości Percentage contribution to sample, % Udział w próbce, % Down hairs Włosy puchowe 1. Length, mm Długość, mm Height, mm Wysokość, mm Height-to-length ratio, % Wysokość w % długości Color band length, mm Długość pasa barwnego, mm Zootechnica 12 (4) 2013

9 10 R. Cholewa et al. Table 1. Arctic fox coat characteristics ( x, SD) continued Tabela 1. Cechy okrywy włosowej lisa polarnego ( x, SD) ciąg dalszy Characteristic Cecha 5. Color band length to hair length, % Długość pasa barwnego w % długości włosa 6. Hair thickness, μm Grubość włosa, μm 7. Core thickness, μm Grubość rdzenia, μm 8. Core thickness to hair thickness, % Grubość rdzenia w % grubości włosa, μm 9. Softness coefficient Współczynnik miękkości 10. Percentage contribution to sample, % Udział w próbce, % Place of sample collection Miejsce pobrania próbek Head Ciemię Back Grzbiet Side Bok Belly Brzuch Tail Ogon Shank Podbudzie x SD x SD x SD x SD x SD x SD Height. The highest coat hairs were found on the side, tail, and back, whereas highest underfur hais were found on the tail. The lowest and the shortest coat hairs were found on the head and the shank, while down hairs on the belly. Height-to-length ratio. The least wavy or corrugated hairs, i.e. showing the highest indices, were found on the tail and the peripheral regions of the body. The lowest value of this characteristic in all hair types was observed on the side. Dark band length. Dark topical bands were present on guard and awn hairs, less frequent on transitional hairs, and completely absent from the hairs of the head and the back. The down hairs lacked this characteristic altogether. The longest dark bands on hairs were found on the back and the shank, the shortest on the other hand on the tail. Dark band length to hair length ratio. The longest dark band in relation to hair length (%) was found in the samples collected on the shank, followed by the head. The shortest, on the other hand, was found on the side and the back. Hair thickness. The thickest hairs within all the studied types were found on the tail, being much thicker as compared to the other parts of the fox s body, which in terms of this characteristic differed only slightly from one another. The thinnest hairs were found on the head and in the case of transitional and awn hairs also on the back. Acta Sci. Pol.

10 Correlation of the traits of fur in arctic foxes Table 2. Analysis of correlation in the characteristics between the body parts Tabela 2. Analiza zależności cech między okolicami ciała No. Characteristics Hair type G B V O P B V O P V O P O P P Lp. Cechy Typ włosa C C C C C G G G G B B B V V O 1. α β Hair length, mm 3. γ Długość włosa, mm 4. δ Σ α β Hair height, mm 7. γ Wysokość włosa, mm 8. δ Σ α β Hair height to length, % 11. γ Wysokość w % długości 12. δ Σ α Length of color band, mm β Długość pasa barwnego, mm γ Σ Length of color band to hair α length, % β Długość pasa barwnego w % γ długości włosa Σ α β Hair thickness, μm 21. γ Grubość włosa, μm 22. δ Σ α β Core thickness, μm 25. γ Grubość rdzenia, μm 26. δ Σ α Core thickness to hair 28. β thickness, % 29. γ Grubość rdzenia w % 30. δ grubości włosa Σ α β Softness index 33. γ Współczynnik miękkości 34. δ Σ α Morphological percentage 36. β composition 37. γ Morfologiczny skład 38. δ procentowy Σ G Back; B Side; V Belly; O Tail; C Head; P Shank; α Guard hairs; β Awn hairs; γ Transitional hairs; δ Down hairs. G grzbiet; B bok; V brzuch; O ogon; C ciemię; P podudzie; α włosy przewodnie; β włosy ościste; γ włosy przejściowe; δ włosy puchowe. Zootechnica 12 (4) 2013

11 12 R. Cholewa et al. Core thickness. The pattern of this characteristic was found similar to that of hair thickness, i.e. the hairs on the tail were characterized by the thickest core, deviating even more than hair thickness on the other parts of the body. The thinnest core was measured in the hairs on the head. Core thickness to hair thickness ratio. This trait was a characteristic of the core volume within the hair. Within the guard hairs, this ratio was the highest in the samples collected from the tail, in the transitional hairs it was equal for the tail and the back, whereas for the down hairs, the core was most bulky on the back followed by the tail. Hair thickness to hair length ratio. The index of softness was highest for the guard hairs on the tail, head, and shank, whereas for the transitional and down hairs on the shank, tail and belly. The softest hairs, i.e. those of the lowest ratio, were the hairs on the back and the side. Morphological composition of the coat. This characteristic was expressed as a percentage composition of the four hair types. The most guard hairs were present on the head, back, and belly, whereas the underfur hairs were most abundant in the samples taken from the tail and the shank. Correlations. The correlation of the individual hair characteristics between the studied parts of the body turned out to be negligible. The degree of dependence resulting from correlational grid diagrams was estimated in points: 0, 1, 2, 3, and in the case of negative correlation with a minus sign. The diagrams rated 2 pts demonstrated correlation coefficients, r, ranging Since for the sample size of 20 specimens the correlation significance threshold is 0.44, further calculations of r for dependences rated 2 pts or less was abandoned. There were only three diagrams rated 3 points. Hence, a correlation of a coefficient r being significant or close to significance was detected in no more than 2% of the diagrams. Estimated correlations are shown in Table 2; this shows that the estimate of 0 prevails, i.e. there is a complete lack of correlation. For a number of 552 diagrams, the following dependences were demonstrated: % % % % % % % Acta Sci. Pol.

12 Correlation of the traits of fur in arctic foxes DISCUSSION Hair coat characteristics presented in this study have been studied by many authors. The research was intended to examine the environmental [Dahlman et al. 2002, 2003] and genetic determinants of these characteristics, or to reveal the sources of their variation [Cholewa 1978, 1983, Piórkowska 2001, Przysiecki et al. 2009]. The sources of variation also generally included the topographic variability, involving the differentiation of fur quality depending on its location on the body [Cholewa 1983, Piórkowska, Natanek 2007]. The most valuable fur is that of the trunk, whereas the fur in the area of the head and the limbs is of much lower quality [Cholewa 2000]. The coat of the arctic fox on the back is thicker, longer, and usually more intensely colored than that on the belly. On the head and the limbs, the fur is much shorter and awn hairs prevail in it. The hair on the tail is longer than on the trunk. The presented results of measurements of the coat characteristics on the back of arctic foxes are similar to those available in the specialist Polish [Cholewa 1978, 1983, 1988], Russian [Syrnikov, Vladimirov 1977], and German literature items [Cholewa 1982]. It is difficult, however, to compare the data coming from other regions of the body, because the worse quality of hairs on them previously discouraged any measurements. The presented analysis of the arctic fox coat characteristics has brought closer the variability of the characteristics on body regions that complement their topographical diversity. The relationships between the same fur characteristics in different parts of the body in the arctic fox were rarely discussed. Only Mejza [1975], using canonical correlation, showed that the relationships between the core thickness of awn, transitional, and down hairs in various regions of the body proved to be statistically non-significant at α = However, this author s finding of a statistically significant correlation between the core thickness of guard hairs located on different body parts proved that it is desireable to search for a method of arctic fox fur evaluation based on physical properties. The data reported in this study revealed of a very weak correlation of a number of morphological hair characteristics between the parts of the body. While it may have partly resulted from the small size of the study group of foxes, it is also very doubtful that examination of a much more numerous population could demonstrate a radical change in the results. In any case, it does not seem possible to base an objective assessment on the measurements of hair from only one part of the body of a polar fox. Zootechnica 12 (4) 2013

13 14 R. Cholewa et al. CONCLUSIONS 1. The mean values of the structural coat characteristics indicates a particular abundance of hair on the tail, and the smallest amount on the head. 2. The most intense coat color was found on the head and the shank, and the poorest on the tail, which also corresponds to the visual evaluation. 3. The correlation in the characteristics between different parts of the body turned out to be negligible statistically non-significant. 4. It is impossible to assess the basic structural characteristics and the dark tops of hairs in the arctic fox fur cover on the basis of a single sample of hair. REFERENCES Cholewa R., Gedymin J., Próba obiektywnej oceny barwy podszycia u lisa polarnego (Alopex lagopus L.) [Attempt of an objective evaluation of underfur color in arctic foxes (Alopex lagopus L.)]. Rocz. AR Pozn., LXXIV, Zootech., [in Polish]. Cholewa R., Badania nad dziedziczeniem niektórych cech morfologicznych okrywy lisa polarnego (Alopex lagopus L.) [Studies on inheritance of selected morphological characteristics of the arctic fox (Alopex lagopus L.) coat]. Rocz. Nauk. Rol., 8, 98, [in Polish]. Cholewa R., Der Pelz der norwegischen und polnischen blauen Polarfüchse im Lichte der Laborforschungen. Dte. Pelztierzücht. 4, Cholewa R., Zmienność z wiekiem cech okrywy włosowej oraz budowy i wielkości niebieskiego lisa polarnego [Age-related variability of hair coat, body structure and size of the blue polar fox]. Rocz. AR Pozn., Rozpr. Nauk., 129, p. 53 [in Polish]. Cholewa R., Chów i hodowla lisów [Farming and Breeding Foxes]. PWRiL, Warszawa [in Polish]. Cholewa R., Chów i hodowla zwierząt futerkowych [Farming and Breeding Fur- Bearing Animals]. Wydaw. AR Pozn., p. 347 [in Polish]. Dahlman T., Valaja J., Niemela P., Jalava T., Influence of protein level and supplementary L-methionine and lysine on growth performance and fur quality of blue Fox (Alopex lagopus). Acta Agric. Scand., A, Animal Sci. 52, Dahlman T., Valaja J., Jalava T., Skrede A., Growth and fur characteristics of blue Fox (Alopex lagopus) fed diets with different protein levels and with or without DL-methionine supplementation in the growing-furring period. Canadian J. Anim. Sci. 83 (2), Gedymin J., Banasiak M., Cholewa R., Próba oceny jakości surowych skór lisów polarnych i norek standard aparatem SGM [Attempt to evaluate the quality of raw pelts of arctic foxes and standard mink using the SGM device]. Mat. Zjazdu Nauk. PTZ, Poznań, 7 8 września 1971 r., Warszawa, [in Polish]. Acta Sci. Pol.

14 Correlation of the traits of fur in arctic foxes Mejza S., Korelacje kanoniczne i ich zastosowanie w badaniach rolniczych [Canonical correlations and their application in agricultural research]. Piąte Colloq. Metodolog., PAN, [in Polish]. Piórkowska M., An attempt at objective evaluation of hair coat value in the blue Fox (Alopex lagopus). Ann. Anim. Sci. 1 (2), Piórkowska M., Natanek A., Ocena jakości okrywy włosowej populacji lisa polarnego z uwzględnieniem obrazu histologicznego skóry [Evaluation of hair coat quality in a population of the arctic fox with respect to the histological image of the skin]. Rocz. Nauk. PTZ 3 (4), [in Polish]. Przysiecki P., Filistowicz A., Gorajewska E., Filistowicz A., Nawrocki Z., Nowicki S., Rehout V., The effect of genotype on coat traits in Arctic Fox during summer and winter season. J. Agrobiol. 26 (1), Syrnikov N.J., Vladimirov A.V., Charakteristika pescovolisich gibridov. Biologija i Patologija Kletočnych Pušnych Zverej, Kirov, Toldt K., Aufbau und natürliche Färbung des Haarkleides der Wildsäugetiere. Deutsche Gesselschaft für Kleintier- und Pelztierzucht. G.m.b.H & Co., Leipzig. WSPÓŁZALEŻNOŚĆ CECH OKRYWY WŁOSOWEJ Z RÓŻNYCH PARTII CIAŁA U LISÓW POLARNYCH (ALOPEX LAGOPUS L.) Streszczenie. Celem pracy było zbadanie możliwości oceny okrywy włosowej lisów polarnych na podstawie zgodności pomiarów laboratoryjnych wykonanych na próbkach włosów z różnych okolic ich futra. Materiał badawczy stanowiły próbki dojrzałej okrywy włosowej 20 dwuletnich samic lisa polarnego niebieskiego, które pobrano w końcu stycznia. Wycięto je przy skórze z 6 miejsc na powierzchni ciała zwierzęcia, które stanowiły: ciemię (między uszami), grzbiet (środek między nasadą ogona a nasadą szyi), bok (poniżej miejsca pobrania próbki grzbietu), brzuch (w połowie odległości między nasadą przednich łap a sromem), ogon (środek strony grzbietowej) oraz podudzie. Próbki poddano pomiarom makro- i mikro-skopowym. Uzyskane wyniki wskazują, że okrywa włosowa lisów polarnych na grzbiecie jest gęściejsza, dłuższa oraz z reguły intensywniej umaszczona niż na brzuchu. Na głowie oraz na kończynach owłosienie jest znacznie krótsze i większy w nim udział mają włosy ościste. Wyniki niniejszej pracy świadczą o bardzo słabej zależności szeregu cech morfologicznych owłosienia między poszczególnymi okolicami ciała. Stwierdzono, że niemożliwa jest ocena obiektywna podstawowych cech strukturalnych i ciemnych wierzchołków włosów w okrywie lisa polarnego na podstawie pomiarów włosów tylko z jednej partii ciała zwierząt. Słowa kluczowe: cechy strukturalne i morfologiczne włosów, lis polarny, okrywa włosowa, zróżnicowanie Accepted for print Zaakceptowano do druku: Zootechnica 12 (4) 2013

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16 Acta Sci. Pol., Zootechnica 12 (4) 2013, ANALYSIS OF CONFORMATION TRAITS OF NEW ZEALAND WHITE RABBITS ON A BREEDING FARM Dorota Kołodziejczyk, Aldona Gontarz, Stanisław Socha Siedlce University of Natural Sciences and Humanities, Poland Abstract. The aim of the study was to analyze the conformation traits of rabbits in relation to the year of evaluation and sex of the animals. The analyzes involved a rabbit production farm located in south-eastern Poland. The farm is specialized in the following breeds: New Zealand White, Blanc de Termonde, Alaska, Californian White, Giant Chinchilla, and Popielno White. The study covered 858 New Zealand White rabbits (741 does and 117 bucks). The ANOVA results indicated statistically significant effect of sex on the quality of the coat, body frame and breed type. The year of evaluation statistically significantly influenced the body size, weight, hair coat quality, specific breed traits, body frame, breed type, and the total score attained by the rabbits. The interaction sex year of evaluation significantly influenced body weight only, whereas no significant effect can be found if we look at the remaining traits. The variation of the traits, as measured with the coefficient of variability, ranged from 1.05 to 9.19%. The correlations were quite varied, ranging from (between the breed type and the year of evaluation) up to (between the body frame and the total score). The analyzed animals were characterized by very good body type and conformation parameters, which is demonstrated by a high score achieved for each trait. Key words: breeding farm, conformation traits, phenotypic correlations, rabbits, statistical analysis, variability INTRODUCTION Domestic rabbit originates from the wild Mediterranean rabbit, whose domestication occurred probably between the years 150 and 100 BC. The domestication resulted in a number of changes observable in both the anatomy and the Corresponding author Adres do korespondencji: dr inż. Dorota Kołodziejczyk, Siedlce University of Natural Sciences and Humanities, Department of Breeding Methods and Poultry and Small Ruminant Breeding, ul. Bolesława Prusa 14, Siedlce, Poland, dormark1@wp.pl

17 18 D. Kołodziejczyk et al. appearance of the body, color and length of hair, or in the behavior of rabbits. First crossing attempts, which can be dated back to the Middle Ages, were carried out in French monasteries. The monks were the first rabbit breeders to artificially cross individuals, which over time led to the emergence of various breeds and utility types [Barabasz, Bieniek 2003]. Currently, rabbits are farmed for pelts, angora wool, and primarily for the nutritious and dietetic meat. The list of top rabbit producing countries includes France, Spain, Italy, China, Egypt, Brazil, and Argentina [Bielański 2004, Bielański, Kowalska 2008]. Important traits to be taken into account in the production of rabbit meat include the structure and the size of the body [Yakubu, Ayoade 2009, Egena et al. 2012]. As a result of the human impact and genetic improvement, the average body weight of rabbits increased dramatically. Currently, the domestic rabbit ranges between 1 and 9 kg in weight, whereas wild rabbits never reach more than kg. Body weight is closely related to its length, in which the domestic rabbit can attain up to 75 cm, as compared to up to 40 cm attainable by the wild form [Niedźwiadek 1984]. Another trait is the color of the coat; the Agouti type of the wild rabbit has transformed into a wide range of color types seen in the today s domestic rabbit. The aim of the study was to analyze the conformation traits of New Zealand White rabbits farmed at a breeding facility located in south-eastern Poland. MATERIAL AND METHODS Data for the study were obtained from a rabbit breeding farm located in southeastern Poland. The farm specializes in various breeds of rabbits, mostly New Zealand White and Blanc de Termonde. To a lesser extent, other breeds, such as Alaska, Californian White, Chinchilla Giant, and Popielno White, are managed on the farm, too. Animals are kept in a cage system and fed pelleted feed in accordance with the relevant rabbit nutrition standards [Barabasz et al. 1994]. The female-to-male ratio on the farm is 8:1, and 6 litters on average are obtained from one female per year. The analysis covered a period of ten years (1994 to 2003), and involved a total of 858 New Zealand White rabbits, including 117 males and 741 females. Evaluation covered animals aged minimum 6 months. Traits under consideration were: body weight, frame, size, breed type, quality of fur, and specific breed traits. The specific breed traits include the color of down hairs, which must be snow-white, eye color (red), and claws (white or fleshcolored). This trait could score a maximum of 20 points. The same point scale was used for evaluation of body frame, breed type and quality of fur. For each of the remaining analyzed traits (size, coat color) the animals could attain a maximum of 10 points [Wzorzec 2000]. For each of the studied traits, the following statistical parameters were calculated: arithmetic means, standard deviations, and Acta Sci. Pol.

18 Analysis of conformation traits of New Zealand White rabbits coefficients of variation. Based on the mathematical model, two-way analysis of variance was performed, which included the year of assessment and the sex of animals. RESULTS AND DISCUSSION The factors that highly significantly affected the body weight of rabbits were: sex and year of the evaluation. Figure 1 shows the mean body weight in relation to sex and year of evaluation. The means shown in Figure 1 reveal that the highest body weight was achieved by females in the eighth year of the study ( g), while the lowest by males in the fifth year of assessment ( g) Males Samce Females Samice Arythmetic mean Średnia arytmetyczna Year of evaluation Rok oceny Fig. 1. Mean body weight of rabbits in grams in relation to sex and the year of evaluation Rys. 1. Średnia masa ciała królików wyrażona w gramach w zależności od płci i roku oceny Bearing in mind how the level of this trait developed over a number of years, it can be seen that in the second year of the study there was a significant decrease in the body weight of females compared to the other years. This could have been a result of some adverse environmental factors, such as, for example, difficult personnel situation at the farm and poor nutrition. For males, these means initially Zootechnica 12 (4) 2013

19 20 D. Kołodziejczyk et al. decreased from the first to the fifth year of the study, both inclusive, then rose and declined alternately (Fig. 1). The body weight is strictly related to the body size, which was expressed in points. Figure 2 presents the arithmetic means of body size of rabbits by gender and the year evaluation. Figure 2 shows that the highest scores were achieved by females in the sixth and eighth year of the study, whereas males attained the highest number of points (10) at the sixth, seventh, eighth, and tenth year of evaluation. 10,2 Males Samce Females Samice 10 Arythmetic mean Średnia arytmetyczna 9,8 9,6 9,4 9,2 9 8,8 8,6 8, Year of evaluation Rok oceny Fig. 2. Descriptive statistics of body size score of rabbits in relation to sex and the year of evaluation Rys. 2. Charakterystyka statystyczna wielkości królików wyrażonej w punktach, w zależności od płci i roku licencji Research on the influence of sex on the growth rate of rabbits have benn carried out for a long time. Ristić [1988] and Staliński et al. [1989] demonstrated that the rate of growth of pure-bred animals is dependent on sex. Parigi-Bini et al. [1992], however, present the opinion that sex is important only in the final stage of fattening. Bieniek [1997] dealt with a related issue, however, and the author noticed differences between the sexes and daily gains in the period from 14 to 42 days of age. A similar view was represented by Zając [2002]. Castellini and Panella [1988], on the other hand, stated that a difference in body weight are seen when the rabbits reach full sexual maturity, i.e. at the age of 4 5 months. Acta Sci. Pol.

20 Analysis of conformation traits of New Zealand White rabbits The year of evaluation and sex highly significantly influenced the quality of fur, which is depicted in Figure 3. Figure 3 indicates that, for both males and females, fur quality was at the highest level in the first year of evaluation. Later on the animals were characterized by a slightly lower quality of hair coat, with the lowest mean values found in males in the third, seventh and tenth year of the study (Fig. 3). 20,5 Males Samce Females Samice 20 Arythmetic mean Średnia arytmetyczna 19, , , Year of evaluation Rok oceny Fig. 3. The average quality of fur of rabbits in relation to sex and the year of evaluation Rys. 3. Średnia jakość okrywy włosowej królików w zależności od płci i roku oceny Analyzing the breed type of the rabbits, it can be seen (Fig. 4) that the maximum number of points (20) received both males and females in the second year, and only males in the third year of the study. The lowest mean was found in males in the last year evaluation. The specific traits of breed, i.e. color of down hair, eyes, and claws, like the breed type, were point-evaluated in the range of 0 20 points. Figure 5 shows the mean number of points achieved by male and female New Zealand White rabbits for specific breed traits over the years of evaluation. Analysis of the results showed that the means remained at a similar level over nearly the entire period studied, reaching usually 20 points, or slightly fewer only in a few cases. The lowest score, points, was attained by males in the last year of evaluation. Zootechnica 12 (4) 2013

21 22 D. Kołodziejczyk et al. 20,5 Males Samce Females Samice 20 Arythmetic mean Średnia arytmetyczna 19, , , , Year of evaluation Rok oceny Fig. 4. Statistical characteristics of the breed type of rabbits in relation to sex and the year of evaluation Rys. 4. Charakterystyka statystyczna typu rasowego królików w zależności od roku oceny i płci zwierząt 20,2 Males Samce Females Samice 20 Arythmetic mean Średnia arytmetyczna 19,8 19,6 19,4 19, , Year of evaluation Rok oceny Fig. 5. Statistical characteristics of specific breed traits of rabbits in relation to sex and the year of evaluation Rys. 5. Charakterystyka statystyczna specyficznych cech rasowych królików w zależności od roku oceny i płci zwierząt Acta Sci. Pol.

22 Analysis of conformation traits of New Zealand White rabbits Another trait significantly affected by sex was the body frame of the rabbits. It is evaluated in 10-point scale, and the evaluator takes into account the harmony in the body shape of the animal. Analyzing the body frame of New Zealand White rabbits, it can be seen that the value of this trait ranged in the subsequent years of study from to The exception is the first year of assessment in which both males and females attained the lowest means for the frame of the body, respectively and 16.6 (Fig. 6). 20 Males Samce Females Samice 19,5 Arythmetic mean Średnia arytmetyczna 19 18, , , , Year of evaluation Rok oceny Fig. 6. Descriptive statistics of body frame of rabbits in relation to sex and the year of evaluation Rys. 6. Charakterystyka statystyczna budowy ciała królików w zależności od płci i roku oceny The results do not differ much from those presented Otulakowski [2011]. The author assessed the body frame of various breeds of rabbits, including the New Zealand White, and found that the average value of body frame assessment in all analyzed breeds was low over the years and never except for one year exceeded 19 points. The author also stated that there were very few rabbits which ware given the model number of points, and the proportion of rabbits with normal body frame was satisfactory only in the case of the New Zealand White breed. By adding up the points achiever for all the evaluated traits, we arrived at arithmetic means of the total score, as shown in Figure 7. Mean values of the general Zootechnica 12 (4) 2013

23 24 D. Kołodziejczyk et al. evaluation of conformation fluctuated in the range to points, so were relatively high. This may prove a good performance and breeding value of the animals. In addition, it can be stated that this breed is one of the best breeds of rabbits reared on Polish farms. The results confirm the studies by Otulakowski [2011], in which the New Zealand White rabbits achieved the highest total conformation score in the group of medium-size breeds of broiler rabbits. 98 Males Samce Females Samice 97 Arythmetic mean Średnia arytmetyczna Year of evaluation Rok oceny Fig. 7. Descriptive statistics of the total score in relation to sex and year of evaluation Rys. 7. Charakterystyka statystyczna łącznej sumy punktów królików w zależności od płci i roku oceny The variability of the studied traits, as measured with the coefficient of variation (Table 1), ranged from 1.05 to 9.19%, depending on the trait. The lowest coefficient of variation was observed for specific breed traits, while the highest for body weight (in kg). The total score was characterized by relatively low variability. This may mean that the animals which were very good in some traits were also slightly inferior in terms of the others, which resulted in equalization of the total score value. Table 2 shows the correlations between the phenotypic characteristics of the examined rabbits. The data reveals that the estimated correlation were quite varied, and ranged from to The lowest correlations were observed between the type of breed and the year of evaluation, the highest ones between Acta Sci. Pol.

24 Analysis of conformation traits of New Zealand White rabbits Table 1. Coefficients of variability for the analyzed traits Tabela 1. Współczynniki zmienności analizowanych cech Trait Cecha Sex Płeć Males Samce Females Samice Total Ogółem Size Wielkość Body frame Budowa ciała Breed type Typ rasowy Hair coat quality Jakość okrywy włosowej Specific breed traits Specyficzne cechy rasowe Body weight, kg Masa ciała, kg Total score Suma punktów Table 2. Phenotypic correlations between the analyzed traits in the population of rabbits Tabela 2. Korelacje fenotypowe pomiędzy analizowanymi cechami w populacji królików Trait Cecha Body size Wielkość zwierząt Body frame Budowa ciała Breed type Typ rasowy Hair coat quality Jakość okrywy włosowej Specific breed traits Specyficzne cechy rasowe Total score Suma punktów Year of evaluation Rok licencji Body weight Masa ciała ** * ** * ** Body size Wielkość zwierząt * ** ** ** ** Body frame Budowa ciała ** ** Breed type Typ rasowy Hair coat quality Jakość okrywy włosowej Specific breed traits Specyficzne cechy rasowe Total score Suma punktów * * ** ** * ** ** * ** ** * differences significant for P 0.05; ** differences significant for P * różnice istotne dla P 0,05; ** różnice wysoce istotne dla P 0,01. Zootechnica 12 (4) 2013

25 26 D. Kołodziejczyk et al. body frame and the total score attained. Both correlations proved highly significant. Correlation is an important measure for the breeder, as it indicates the existence of a relationship between various traits in the same subject. The correlation coefficient, ranging from 1 to +1, is a measure of this relationship between traits. As long as the coefficient remains within the range 1 to 0, the correlation is negative, which means that an improvement in one trait will result in deterioration of another. If the coefficient ranges from 0 to +1, the correlation is positive, indicating an improvement in both traits [Barabasz, Bieniek 2003]. Positive correlations between the analyzed traits and the year of evaluation, obtained in this study, indicate an increase in the value of a given trait over the study period, whereas negative correlations indicate a decline in the value of the trait over the 10-year period of observations. CONCLUSIONS 1. Rabbits are animals that are bred and evaluated in a different way than in the case of other fur-bearing animals. One of the main differences is the 100-point model for conformation assessment, which includes the 6 traits. 2. The evaluated rabbits attained a high score for individual traits, which leads to a conclusion that the animals were characterized by very good parameters of shape and conformation. The New Zealand White rabbit is one of the most popular rabbit breeds, farmed also in Poland, and at the same time a breed most suitable for intensive farming. 3. The animals were of good quality both in terms of performance and breeding value. The positive correlations found in this study between the evaluated traits (body weight, size in points and body frame) and the year of evaluation indicate a growth in this trait over the studied period, whereas negative correlations between the remaining traits (breed type, hair coat quality, specific breed traits, and total score attained) and the year of evaluation indicate a slight decline in the value of the traits over the studied decade. REFERENCES Barabasz B., Bielański P., Jarosz S., Sławoń J., Normy żywienia mięsożernych i roślinożernych zwierząt futerkowych [Nutrition standards for carnivorous and herbivorous fur animals]. Instytut Fizjologii i Żywienia Zwierząt PAN [in Polish]. Barabasz B., Bieniek J., Króliki. Towarowa produkcja mięsna [Rabbits. Commodity meat production]. PWRiL Warszawa [in Polish]. Acta Sci. Pol.

26 Analysis of conformation traits of New Zealand White rabbits Bielański P., Wpływ rasy i systemów utrzymania na cechy produkcyjne brojlerów króliczych [Effect of breed and housing systems on production traits of broiler rabbits]. Instytut Zootechniki Kraków, 282. [in Polish]. Bielański P., Kowalska D., Królik nieznany czy znany? Cz. I. Polska [Rabbit known or rather unknown? Part I, Poland] Mag. Weter. [in Polish]. Bieniek J., Wpływ czynników genetycznych i środowiskowych na użytkowość mięsną królików w warunkach chowu tradycyjnego [Effect of genetic and environmental factors on rabbit slaughter value under traditional farming conditions]. Zesz. Nauk. AR, Kraków. [in Polish]. Castellini C., Panella F., Heritability of pre- and post-weaning weights in rabbits. Proc. 4th World Rabbit Congress, Budapest, Hungary, 2, Egena S.S.A., Akpa G.N., Aremu A., Alemede I.C., Predicting body weight of Rabbit from linear body measurements at various ages by genetic group, parity and sex. 10th World Rabbit Congress, September 3 6, Egypt, Niedźwiadek S., Zasady hodowli królików [The Principles of Rabbit Breeding]. PWRiL Warszawa. [in Polish]. Otulakowski G., Analiza genetyczna i fenotypowa cech pokroju i wskaźników rozrodu wybranych ras królików. Rozprawa doktorska [Genetic and phenotypic analysis of conformation traits and reproduction parameters of selected rabbit breeds. PhD Dissertation]. UP Wrocław. [in Polish]. Parigi-Bini R., Xiccato G., Cinetto M., Zotte A.D., Converso R., Effect of age, slaugter weight and sex on carcass and meat quality. Zootech. Nutr. Anim., 18, 3 4, Ristić M., Einfluss von Geschlecht und Mastengewicht auf den Schlachtkörperwert von Jungmastkaninchen. Proc. From the 6th Symposium on Housing and Diseases of Rabbits, Furbearing Animals and Pet Animals, Celle, Germany, Staliński Z., Bieniek J., Drożyńska D., Ptak E., Stobiecka D., Wpływ rasy, płci, oraz systemu żywienia na wzrost i niektóre cechy użytkowości mięsnej królików [Effect of breed, sex, and feeding system on the growth and selected slaughter value traits of rabbits]. Pr. Mat. Zootech. 39, [in Polish]. Wzorzec królików [Rabbit Model]. CSHZ, Warszawa [in Polish]. Yakubu A., Ayoade J.A., Application of Principal Component Factor Analysis in Quantifying Size and Morphological Indices of Domestic Rabbits. Int. J. Morphol., 27 (4), Zootechnica 12 (4) 2013