PERFORMANCE TEST OF YOUNG CROSSBRED BOARS FROM THE BYDGOSZCZ BREEDING REGION IN POLAND

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1 1255 Bulgarian Journal of Agricultural Science, 20 (No 5) 2014, Agricultural Academy PERFORMANCE TEST OF YOUNG CROSSBRED BOARS FROM THE BYDGOSZCZ BREEDING REGION IN POLAND G. Michalka, J. Nowachowicz, T. Bucek, P. D. Wailewki* and M. Kmiecik Univerity of Technology and Life Science in Bydgozcz, Faculty of Animal Breeding and Biology, Department of Poultry Breeding and Animal Product Evaluation, Bydgozcz, Poland Abtract Michalka, G., J. Nowachowicz, T. Bucek, P. D. Wailewki and M. Kmiecik, Performance tet of young crobred boar from the Bydgozcz breeding region in Poland. Bulg. J. Agric. Sci., 20: The aim of preented reearch wa performance tet analyi of young crobred boar came from 6 croing variant conducted in year 2009 and 2010 in Poland, in The Bydgozcz Breeding Region. The reearch covered the performance tet reult of 1911 young crobred boar conducted with accordance to obligatory modified methodology. The animal came from the following croing variant (ow breed given in the firt poition): Hamphire Duroc (H D), Hamphire Pietrain (H P), Duroc Hamphire (D H), Duroc Pietrain (D P), Pietrain Hamphire (P H) and Pietrain Duroc (P D). Duroc Hamphire young crobred boar had the highet growth rate, the thinnet backfat, the highet height of loin eye and the highet election inde value. The highet meat content in 2009 had animal of Pietrain Duroc and Hamphire Pietrain, and in 2010 Duroc Hamphire pig. Analying the reult from year 2009 and 2010 it wa obered that the increae of performance tet election inde value occurred in crobred of Hamphire Duroc, Hamphire Pietrain and Pietrain Duroc (by 4, 4 and 2 point, repectively). In cae of the remaining group of pig deterioration (by 1-2 point) of performance tet election inde ha been oberved or there wa no change. Key word: young crobred boar, performance tet, growth rate, meat content Introduction Crobred boar are becoming increaingly important in modern pig croing program, both in Poland and in other countrie. Reult of many tudie (Czarnecki et al., 1999a, b; Michalka et al., 2004; Milewka 2007; Milewka and Falkowki, 2001; Nowachowicz et al., 2009; Różycki, 1995) indicate their uitability for commercial croing. Crobred boar compared with pure breed animal are characterized by earlier puberty, heavier teticle weight, higher volume of better quality emen, greater uitability for breeding becaue of the increaed libido and better efficacy of mating and the poibility of their prolonged ue (Czarnecki et al., 1999a; Fent et al., 1980; Kapelańki, 1995; Knap, 1987; Koczanowki et al., 2001; Michalka, 1996; Michalka et al., 2004, 2010; Michalki and Polańka, 1983; Milewka, 2007; Milewka and Falkowki, 2001; Neely and Robion, 1983; Nowachowicz, 2004; Nowachowicz et al., 2009; Rak et al., 1993; Różycki, 1995). Performance tet reult are one of the main criteria in the election work over the pig in the election of animal for breeding and production herd (Różycki, 2003). Performance tet play a pecial role in the conducted election, epecially male individual, becaue of their breeding value depend largely on the productivity of breeding and ma herd. Therefore, it would be adviable, to know not only the propertie of boar of particular pig breed and line, but alo variant of their croing (Czarnecki, 1999a, b; Eckert and Szyndler-Nędza, 2010, 2011; Michalka, 1996; Michalka and Nowachowicz, 2000, 2002; Michalka et al., 1998, 2000; Różycki, 1995, 1997; Różycki et al., 1980, 1986). Among the paternal component of pig performance teted in our country, including Bydgozcz Breeding Region in recent year net to the boar of following breed uch a: Hamphire, Duroc, Pietrain and Synthetic Line 990 there are alo two-breed crobred young boar came from their reciprocal croing (Eckert and Szyndler-Nędza, 2010, 2011). In the national literature there i a lack of the reult regard- *Correponding author: przemek@utp.edu.pl

2 1256 G. Michalka, J. Nowachowicz, T. Bucek, P. D. Wailewki and M. Kmiecik ing the young crobred boar performance tet. In annually publihed by the Intitute of Animal Production in Balice PIB regiter Statu of breeding and evaluation reult of pig i given only the total reult of performance tet of all crobred. However, the reult of young crobred boar came from pecified pig croing variant are not given. The aim of preented tudy wa the analyi of young crobred boar performance tet came from 6 croing variant, carried out in year 2009 and 2010 in Poland in The Bydgozcz Breeding Region. Material and Method The tatitical analyi covered the reult of performance tet of 1911 young crobred boar produced in Poland, in The Bydgozcz Breeding Region in year 2009 and 2010 according to obligatory modified methodology, which in calculation of the election inde take into account daily gain of body weight tandardized on 180 th day and percentage body meat content (Eckert and Szyndler-Nędza, 2011). Young boar came from the following croing variant (ow breed in firt poition): Hamphire Duroc (H D), Hamphire Pietrain (H P), Duroc Hamphire (D H), Duroc Pietrain (D P), Pietrain Hamphire (P H) and Pietrain Duroc (P D). The performance tet election inde formula wa a follow (Eckert and Szyndler-Nędza, 2011): for paternal line: I O = 0.64 X X , where: X 1 daily gain tandardized on 180 day of life, X 2 percentage meat content etimated on the bae of tandardized backfat thickne and loin mucle meaurement on 110 kg, then tandardized on 180 th day of life. The reult were tatitically elaborated uing one-way ANOVA variance analyi. Calculation were made uing computer program Statitica 8.0 PL (2008). Reult The number of young crobred boar in 6 teted group, performance tet reult, including growth and laughter trait and the election inde value were preented in Table 1 and 2. Among animal performance teted in The Bydgozcz Breeding Region the mot numerou were Duroc Pietrain crobred (in pc., in pc.), then Pietrain Duroc crobred (in pc., in pc.). Among the remaining crobred group the net in term of the number were animal of Pietrain Hamphire (in pc., in pc.), Hamphire Pietrain (in pc., in pc.) and Hamphire Duroc (in pc.). The mallet group in 2009 were Duroc Hamphire (17 pc.) in 2010 young boar of Duroc Hamphire ( pc.) and Hamphire Duroc ( pc.). The younget on performance tet day in analyzed year (2009 and 2010) were young crobred boar Duroc Hamp- Table 1 Performance tet reult of young crobred boar in year 2009 Trait H D 1 H P 2 D H 3 Group D P 4 Number, pc Age on the tet day, day Body weight on the tet day, kg Daily gain of body weight tandardized on 180 th day, g Average backfat thickne, mm Standardized height of loin eye, mm Standardized body meat content, % Performance tet election inde, point Significance of difference P H P D 5 6 Total P 0.01 P ,2,4,5,6 6-4,5 1-,3,5; 3-4,5,6 5-2,4,6 4-5,6 2-3,4, , ,2 1-3,4, ,3,4,6 1-5,6 5-4,6 -

3 Performance Tet of Young Crobred Boar 1257 hire, 160 and 167 day, repectively. The oldet were pig of Pietrain Duroc, both in 2009 and 2010 (181 and 180 day, repectively) and the difference between them and the remaining group were generally tatitically ignificant (Table 1 and 2). The heaviet body weight on the tet day in eamined year (2009 and 2010) had Duroc Hamphire crobred, 129 and 127 kg, repectively. The difference between them and the remaining group of animal were verified in the mot cae a tatitically high ignificant (Table 1 and 2). Net regarding to the analyzed trait in 2009 were young boar of Hamphire Pietrain (124 kg), Hamphire Duroc (122 kg), Duroc Pietrain, Pietrain Duroc (120 kg) and Pietrain Hamphire (102 kg). In 2010 the young boar order in range of thi trait wa imilar and haped a follow: Hamphire Duroc (123 kg), Hamphire Pietrain (120 kg), Duroc Pietrain, Pietrain Duroc (119 kg) and Pietrain Hamphire (106 kg). Both in 2009 and 2010 Pietrain Hamphire young crobred boar had tatitically ignificant (P 0.01) lower body weight on the performance tet day compared to the remaining teted group of pig. Daily gain of body weight tandardized on 180 th day of life of young crobred boar coming from all analyzed group wa in g and in g, averagely. The highet growth rate in both teted year (2009 and 2010) had Duroc Hamphire pig (864 and 795 g, repectively) - Table 1 and 2. Difference in daily gain of body weight in 2009 between above mentioned the bet group (Duroc Hamphire) and the remaining crobred were (in gram): 128 (D P), 140 (H D), 148 (H P), 198 (P D) and 239 (P H), repectively. However, in 2010 between the ame crobred (Duroc Hamphire) and other group of animal were lower and haped a follow: 64 (H P), 78 (D P), 86 (H D), 123 (P D) and 196 (P H) and were tatitically high ignificant. Backfat thickne of performance teted young crobred boar in 2009 amounted averagely 9.0 mm, and in mm. The thinnet backfat in 2009 had individual of Duroc Hamphire, Duroc Pietrain, Pietrain Hamphire, Pietrain Duroc (8.7; 8.8; 8.8; 9.0 mm repectively) and in 2010 Duroc Hamphire, Pietrain Duroc, Duroc Pietrain and Pietrain Hamphire (8.5; 8.6; 8.7 and 8.7 mm, repectively). The thicket layer of ubcutaneou fat in 2009 had crobred of Hamphire Pietrain (9.6 mm) and Hamphire Duroc (9.4 mm) - P 0.01 and P 0.05 (Table 1 and 2), however in 2010 pig of Hamphire Duroc and Hamphire Pietrain (9.3 mm). Standardized height of loin eye of young crobred boar meaured in P 4 point regarding to the reult from analyzed year (2009 and 2010) haped at the average level of 57.6 and 58.1 mm, repectively. The highet height of loin eye in 2009 had young boar of Duroc Hamphire (58.8 mm), and in 2010 animal of Hamphire Pietrain and Duroc Hamphire (61.4 mm). The lowet height of loin eye in 2009 had pig of Pietrain Duroc (57.3 mm), and in 2010 crobred of Pietrain Hamphire (57.3 mm) - Table 1 and 2. Body meat content i an important parameter affecting a production and economic reult of pig. Therefore, it i Table 2 Performance tet reult of young crobred boar in year 2010 Trait H D 1 H P 2 D H 3 Group D P 4 P H 5 P D 6 Total Number, pc Age on the tet day, day Body weight on the tet day, kg Daily gain of body weight tandardized on 180 th day, g Average backfat thickne, mm Standardized height of loin eye, mm Standardized body meat content, % Performance tet election inde, point Significance of difference P ,5,6 P , ,2,3,4,6 3-4,6 5-4,6 6-2, ,3-4,5,6 1-2,3 5-1,2,3,6-5-4,6 -

4 1258 G. Michalka, J. Nowachowicz, T. Bucek, P. D. Wailewki and M. Kmiecik one of the mot important indicator taken into account during the election of the animal. The average tandardized body meat content of all teted young crobred boar performance teted in The Bydgozcz Breeding Region in 2009 amounted 60.6% and in 2010 wa higher by 0.5% and haped at the level 61.1%. The highet body meat content in 2009 had crobred of Pietrain Duroc 61.2 %, however in 2010 young boar of Duroc Hamphire (62.2%). The net in the tet conducted in 2009 were young boar of Hamphire Pietrain (61.1%), Duroc Hamphire (60.6%), Duroc Pietrain (60.5%), Hamphire Duroc (60.4%) and in 2010 pig of Pietrain Duroc (61.7%), Hamphire Duroc (61.6%), Hamphire Pietrain (61.5%), Duroc Pietrain (61.0%). However, young crobred boar of Pietrain Hamphire performance teted in year 2009 and 2010 had the lowet meat content amounted 59.5 and 60.2%, repectively and the difference in thi range between them and pig from remaining croing variant (ecept young boar of Duroc Pietrain performance teted in 2010) were tatitically high ignificant (Table 1 and 2). The mot important performance tet parameter of pig i the election inde, which determine the own uability of animal. The average election inde value of all teted young boar in 2009 haped at the level 112 point, however in 2010 amounted 111 point, thu decreaed inignificantly (by 1.0 point). On the bae of the reult given in Table 1 and 2 it hould be tated that in year 2009 and 2010 among 6 group of young crobred boar coming from The Bydgozcz Breeding Region the highet performance tet election inde value had the le numerou Duroc Hamphire crobred (2 and 0 point), and the difference between thi group of animal and the remaining were confirmed at the P 0.01 ignificance level. The net in term of thi trait in 2009 were young boar of: Duroc Pietrain (1 pt), Hamphire Pietrain (114 pt), Hamphire Duroc (112 pt), Pietrain Duroc (109 pt) and Pietrain Hamphire (94 pt), however in 2010 were crobred of: Hamphire Pietrain (118 pt), Hamphire Duroc (116 pt), Duroc Pietrain (114 pt) Pietrain Duroc (111 pt) and Pietrain Hamphire (94 pt). The difference of analyzed trait epreed in point in 2009 between the bet 3 rd group (Duroc Hamphire) and the remaining crobred of pig amounted from 17 (D P, group 4) up to 38 (P H, group 5). Alo, in year 2010 imilar trend were oberved, becaue the difference between Duroc Hamphire young boar and the remaining group of animal amounted from 12 (H P, group 2) up to 36 (P H, group 5). Comparing the reult from 2009 and 2010 it hould be noted that the performance tet election inde of pig Duroc Hamphire and Duroc Pietrain decreaed by 2 and 1 point, repectively. A regard young crobred boar of Hamphire Duroc, Hamphire Pietrain and Pietrain Duroc increaed by 4, 4 and 2 point. In Pietrain Hamphire crobred, which obtained the wort performance tet election inde value there were no change in it value in the tudied year (Table 1 and 2). Dicuion The reult of Grudniewka and Milewka (2000), Michalka et al. (1998), Milewka and Falkowki (2001) and Milewka and Grudniewka (1999) indicate that the animal of Duroc breed had higher daily gain of body weight compared to Hamphire and Pietrain pig. In another tudie (Bucek, 2009; Chojnacki, 2004; Michalka, 2001; Michalka and Nowachowicz, 2000, 2002; Michalka et al., 2000) regarding pig performance teted in The Bydgozcz Breeding Region in year and Duroc young boar and crobred with thi breed alo had the highet growth rate. Milewka and Falkowki (2001) oberved unlike in the preent tudy, that among performance teted young crobred boar coming from OSHZ in Olztyn the highet daily gain of body weight had P D group. Similarly, Eckert and Żak (1999) proved higher growth rate of young crobred boar P D compared to P H animal amounting 646 and 626 g, repectively. In another tudie Eckert and Żak (2002) report that regarding to the daily gain of body weight the heteroi effect wa higher in pig coming from Duroc Pietrain croing variant than Pietrain Duroc and haped in young boar and gilt at a level of 3.37 and 2.18%, repectively. In the reearch of Bucek (2009), regarding young boar performance tet reult in The Bydgozcz Breeding Region in year , among 9 two-breed crobred the bet reult in range of analyzed trait had the animal coming from three croing variant: BL D (644 g), P H (648 g) and P D (639 g). Average daily gain of body weight of teted crobred coming from The Bydgozcz Breeding Region in 2009 (714 g) and 2010 (689 g) wa comparable to the average value of all young crobred boar performance teted in whole country amounted in g and in g, repectively (Eckert and Szyndler-Nędza, 2010, 2011). In the tudy of Michalka et al. (2010) among 6 teted croing variant group, young crobred boar Hamphire Pietrain (H P) had the mot favourable reult regarding to daily gain of body weight tandardized on 180 th day of life, conequently, the reult in thi regard haped differently than in the preented publication. On the other hand, Nowachowicz et al. (2009) howed that the highet growth rate among F 1 young crobred boar performance teted in The Bydgozcz Breeding Region had Pietrain Hamphire (637 g) animal.

5 Performance Tet of Young Crobred Boar 1259 In the previou own reearch (Michalka et al., 2010) among 6 two-breed croing variant the highet meat content had Hamphire Pietrain group, however in other reearch (Michalka et al., 1997) regarding to the performance tet of 11 young crobred boar the highet meat content had Pietrain Hamphire individual. Animal of Pietrain breed, due to it outtanding meat content, are ued in crobreeding program applied in many European countrie (Arent et al., 1988; Czarnecki et al., 1999a, b; Michalka et al., 1998, 2010; Milewka and Falkowki, 2001; Rak et al., 1993). Milewka and Falkowki (2001) oberved that among teted young crobred boar the highet election inde value had Pietrain Duroc and Pietrain Hamphire animal, what i conitent with the reult in preented paper. In the reearch of Eckert and Żak (1999) tatitically high ignificant difference in election inde were proved between F 1 crobred Pietrain ow Duroc boar (126 point) comparing to crobred Pietrain ow Duroc boar (123 point), what indicate that Pietrain ow croed with Duroc boar produce more valuable young crobred boar comparing to the animal coming from Pietrain ow and Hamphire boar. Chojnacki (2004) howed otherwie a in the preent work, that among young crobred boar produced in The Bydgozcz Breeding Region in year and eamined under the old methodology of performance tet, the bet reult of election inde had pig came from Pietrain Hamphire croing variant (127 point). In the reearch of Michalka et al. (2010) otherwie than in the preent reearch it wa proved that the mot favourable reult of performance tet election inde among eamined 6 croing variant had Hamphire Pietrain young crobred boar. Concluion Summarizing obtained reult of reearch it hould be noted that among young crobred boar performance teted in The Bydgozcz Breeding Region in year 2009 and 2010 Duroc Pietrain pig had the highet growth rate, the thinnet backfat, the highet height of loin eye and the highet election inde value. The highet meat content in 2009 had young boar of Pietrain Duroc and Hamphire Pietrain, and in 2010 Duroc Hamphire pig. Analyzing the reult from year 2009 and 2010 it wa oberved that the increae of performance tet election inde value occurred in crobred of Hamphire Duroc, Hamphire Pietrain and Pietrain Duroc (by 4, 4 and 2 point, repectively). In cae of the remaining group of pig deterioration (by 1-2 point) of performance tet election inde ha been oberved or there wa no change. Reference Arent, E., j. Pavlik and J. Pulkrábek, Aement of variability production trait of paternal breed of pig. Živočišna Výroba, 33 (8): (Cz). 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