Association between subcutaneous and intramuscular fat content in porcine ham and loin depending on age, breed and FABP3 and LEPR genes transcript abundance

M Tyra,K Ropka-Molik,K Piórkowska,A Bereta,A Terman,M Oczkowicz

doi:10.1007/s11033-012-2311-7

Abstract

The objective of the present study was to analyze the level of intramuscular fat (IMF) in loin (musculus longissimus dorsi) and ham (musculus semimembranosus) and the level of subcutaneous fat in these cuts depending on breed, age and the expression level of FABP3 and LEPR genes. The results obtained showed that only the breed influenced on the level of both intramuscular and subcutaneous fat to the same extent (P ≤ 0.001). The age of animals had an effect on fat content of the cuts (P ≤ 0.001) and to a lower extent on the level of IMF in both muscles (P ≤ 0.05). We confirmed highly significant effect of breed and age on the LEPR mRNA abundance—the expression of the this gene increased significantly (P ≤ 0.01) with age and the highest expression was found for the Puławska breed in m. longissimus dorsi and for the Polish Landrace breed in m. semimembranosus. We observed the high correlations between the transcript level of the LEPR gene and the fat content of individual cuts (P ≤ 0.01). The expression level of FABP3 gene influenced the level of IMF (P ≤ 0.01), but not the level of subcutaneous fat in loin and ham.

Highlights

It is well known that intramuscular fat (IMF) plays an important role both in the sensory evaluation of meat and meat products and in the suitability of meat for technological processing
In present study we analyzed the significance of factors that may influence on the level of loin and ham fatness traits (Tables 1, 2)
The analysis that accounted for the effect of breed and age (Fig. 1; Table 3) showed that the level of IMF was significantly lower in m. semimembranosus compared to m. longissimus dorsi

Summary

Introduction

It is well known that intramuscular fat (IMF) plays an important role both in the sensory evaluation of meat and meat products and in the suitability of meat for technological processing. The direction of selection, which has been observed in recent years, results from efforts to eliminate the consequences of long-term marginalization of fatness traits due to selection pressure for increased carcass meatiness. This caused a considerable increase in the growth rate of pigs while having a negative effect in the form of lower IMF levels. In the Polish population of pigs, the level of IMF began to decrease at an alarming rate for the most numerous breeds (Polish Landrace and Polish Large White) [1, 2]. Even among highproducing pigs there are breeds characterized by rewarding IMF levels, as exemplified by the Duroc breed. In Polish breeding, there is one local breed (Puławska) characterized by a high ([2 %) level of intramuscular [2]

Objectives

Methods

Results

Conclusion