Variation of lipogenesis in pig adipocytes and adipose tissues

Abstract

In the past, the pig was considered as a fat supplier. In the 1950s, consumers examined this fatness critically. Genetic selection and rearing conditions have greatly improved body composition towards a higher lean meat content and a lower fat deposition. Lipogenesis has been studied in order to explain the growth and the development of adipose tissues. Most of these studies which were carried out a long time ago and which concerned the external adipose tissues, need to be actualised. Now, pig adiposity is below twenty percent, but in 1960, it was over forty percent.

Recent experiments have investigated the development of intramuscular adipose tissue in relation with organoleptic meat qualities. Adipocytes from intramuscular adipose tissue are located along muscle fibres. Lipid synthesis of adipocytes from intramuscular adipose tissue is higher than that of adipocytes from external adipose tissue. The stimulation of lipogenesis can be envisaged in order to increase intramuscular lipid content, but the limiting factor will probably be the number of adipocytes. It will therefore be necessary to stimulate adipocyte proliferation and to gain a better knowledge of the mechanisms that control their proliferation. These investigations will also concern other animals whose meat presents a low lipid content, such as poultry and rabbits.