제주 흑돼지 가계특성 별 돈육질 및 근육조직학적 특성 분석

Abstract

Jeju black pig is well known for the good preference from consumers and its excellent meat quality and property. But, the quality is not equalized for each raising farm, nor standardized either and the variation is huge for each farm comparing with its famous brand image. The reason for that is that the breed of Jeju black pig has not been established clearly yet. So, Jeju needs to reduce the variations for each farm through breed definition of Jeju black pig and it is the right time for Jeju black pig raising business to be constant and developmental through the standardization of quality and carcass. For that, this study was carried out to arrange most optimal cross combination for breed establishment of Jeju black pig and basic data for formation of breed targeting the raising farms of Jeju black pig through the analysis of reproductive characteristics, carcass characteristics, characteristics of meat quality and histochemical characteristics of Jeju black pig by the produced piglets from each breed & cross combination.

For this study, the evaluation of semen for diseases (turned out to be negative for all as the results of PRRSV & PCV-2 tests) were completed against 18 candidate boars for performance test of boars of Jeju black pig and 9 were selected. Total 4 experimental farms were selected for progeny test and artificial insemination was completed against total 134 sows. The produced piglets based on that were total 1,000 and, as the results of analyzing black piglets, 96.7% appeared black color and another color appeared from 33 piglets (3.3%) only. The produced number for each candidate gilt was recognized as 9.8 for average, 8.7 for number of born alive and 7.3kg for weaning weight.

As the results of analyzing growth performance for each experimental farm, it could be recognized that the change of carcass weight along raising term was influenced more by environmental factors such as performance control and raising environment. As the results of analyzing meat quality for each experimental farm, it could be recognized that it was influenced more by environmental factors such as performance control, raising environment and etc. than that of raising term and carcass percentage. As the results of analyzing the characteristics of growth performance of candidate boars, they showed the similar results as growth performance for experimental farm and it could be recognized that it was influenced more by environmental & genetic factors such as breed, cross combination, gender and performance control than raising term and weight gain. It showed the identical result with the research result of Choi et al.(2009). It was recognized that characteristics of meat quality for each boar candidate was influenced more by environmental factor as well. It could be recognized that environmental & genetic factors such as breed, cross combination, gender and performance control influence more than raising term and carcass weight regarding growth characteristics and carcass characteristics.

Histochemical analysis was performed to analyze the qualitative characteristics among candidate boars. High performance group 20% (MK001 & MK003) and low performance group 20% (MS001 & MK002) which are excellent in histochemical respect were selected and comparative analysis was performed for histochemical analysis.

As the result of performing comparative measurement against muscle fiber area for histochemical analysis, it showed significant difference slightly, but the measured value of muscle fiber area of Type Ⅰ and Type Ⅱb turned out to be large in the Low performance group. But, regarding muscle fiber number percentage & muscle area number percentage, the measured value turned out to be higher at the high performance group than the low performance group. It was measured that the low performance group 20% (MS001 & MK002) showed the higher values regarding whole size of muscle fiber, size & density of Type Ⅱb, but the high performance group 20% (MK001 & MK003) showed the higher values regarding size & density of Type Ⅰ. It showed the identical tendency with the research results of Lee (2003) that says that the number of muscle fibers was in inverse proportion with size of muscle fiber and the density of muscle fiber was in direct correlation with the number of muscle fibers.

As the analysis results, it showed the similar values regarding carcass weight, backfat thickness, temperature and etc., but there existed the differences between pH, brightness, drip loss, cooking loss and hardness. The high performance group 20% (MK001, MK003) was higher than the low performance group 20% (MS001 & MK002) by pH45min & 24hour and it showed the darker color regarding brightness as well ( P < 0.05). The high performance group 20% (MK001, MK003) was superior to the low performance group 20% (MS001 & MK002) regarding drip loss and cooking loss and received the better evaluation regarding meat color ( P < 0.05) as well. The high performance group 20% (MK001, MK003) showed the higher result than the low performance group 20% (MS001 & MK002) regarding the comparative analysis of hardness and chewiness that express the feeling when eating the meat as well ( P < 0.05). The high performance group 20% (MK001, MK003) which had more number of muscle fibers than the low performance group 20% (MS001 & MK002) had the higher in pH, good meat color and excellent drip loss. And, it was excellent regarding cooking loss and hardness as well ( P < 0.05). It showed the similar result with the result announced by Lee (2003) analyzing the number & growth of muscle fibers and meat quality of carcass that the group with more number of muscle fibers was superior regarding growing performance and producing performance of lean-meat.

The correlation analysis was performed to analyze the correlation among the measured items. The various correlations between items of histochemical characteristics and meat quality characteristics could be wholly observed. As the result of measuring post-pH items, Type Ⅰ area(%) showed the direct correlation and Type Ⅱb area(%) showed the negative correlation. Regarding the measured value of brightness(L*) that indicates the meat color of meat, it showed the negative correlation in case of Type Ⅰ area(%) and Type Ⅱb area(%) showed the direct correlation. As the result of measuring drip loss(%) that measures the drip loss of meat, Type Ⅰ area(%) showed the negative correlation and Type Ⅱb(%) showed the direct correlation. As the result of measuring hardness that is related with the feeling of meat, Type Ⅰ area(%) showed the direct correlation and Type Ⅱb area(%) showed the negative correlation. To analyze that, it showed the direct correlation in the meat quality-related items except for brightness and drip loss in case of Type Ⅰ area(%) and Type Ⅱb(%) showed the opposite measured results. The high performance group that has the excellent histochemical characteristics and meat quality was higher regarding muscle fiber area percentage and the low performance group was low performance regarding muscle fiber area percentage comparing with that. pH that loads huge influences on post-characteristics of carcass was kept higher in the high performance group that has the higher muscle fiber area percentage comparing with the low performance group, meat color was darker and drip loss & hardness were measured as excellent. It could be recognized that the density of muscle fiber has the close correlation with meat quality of carcass through that.

As the results of this study, there were huge differences regarding growth characteristics and growth performance of the progeny black piglets produced from cross combination of candidate boars depending on performance control and raising environment of the farms. It is judged that more uniform and standardized carcass can be commercialized than now if establishes performance management, control of raising environment or unified cultivation system. On the contrary, as the results of analyzing the characteristics of meat quality and histochemical characteristics that decide the quality of good, it was analyzed that the characteristics of meat quality and histochemical characteristics of candidate black piglets produced from the candidate boars were influenced much by heritability of the candidate boars. As much as it is candidate boar with excellent meat quality, it was analyzed that the size of muscle fiber was small and distribution density of muscle fiber Type 1 was higher. It was analyzed that such distribution density of muscle fiber influences on pH, drip loss & meat color of carcass and final meat quality much. It is judged that the profits of farms can be produced by selecting the excellent breeding pig whose capability of producing good meat quality and the excellent breed and cross combination can be selected continuously by registering, preserving and improving the excellent breeding pig through that.