Lipogenesis and Lipolysis in Normal and Dwarf Chickens from Lines Selected for High and Low Body Weight

Abstract

Lipogenic and lipolytic comparisons were made among normal and dwarf adult males from both high-weight (HW) and low-weight (LW) selected lines. Six nonfasted birds from each of the four populations were sacrificed, and in vitro lipogenesis and lipolysis were measured in liver, adipose, and bone tissue. Also determined were activities of acetyl CoA carboxylase (E.C.6.4.1.2), NADP-malate dehydrogenase (E.C.1.1.1.40), ATP-citrate lyase (E.C.4.1.3.8), and plasma-free fatty acids (FFA). In comparison with the HW chickens, the LW males tended to exhibit higher activities of lipogenic enzymes, a greater capacity to incorporate acetate-1-14C into liver slices, an increased mobilization of FFA from adipose tissue, and high concentrations of FFA in plasma. The results indicated that the maintenance of increased postmaturational body fat associated with selection for high body weight was primarily the result of decreased lipolysis rather than enhanced lipogenesis. Effects of the dwarf allele on lipogenesis and lipolysis were not clear. Acetate incorporation into bone tissue was substantially higher than for adipose tissue, suggesting that bone may be an important site of lipogenesis in the fowl.

Lipogenesis and Lipolysis in Fed and Fasted Chicks from High and Low Body Weight Lines

“…The results of this experiment in which chicks were examined at 28 days of age were consistent with those obtained with adult chickens (Calabotta et al, 1983). At both ages, chicks from the LW line exhibited increased lipogenic and lipolytic capacities when compared to their HW counterparts.…”

“…Calabotta et al (1983) compared lipogenic and lipolytic capacities between adult males from two divergent lines developed through selection for body weight at 8 weeks of age (Siegel and Cherry, 1981). Their results suggested that, at least in mature males, lipid turnover differed between these lines.…”

“…Comparisons were made when chicks were in both fed and fasted states. In addition, because of recent evidence that the skeleton might be an important lipogenic site in the domestic chicken (Nir and Lin, 1982;Calabotta et al, 1983), bone tissue was examined for the presence of lipogenic enzyme activity.…”

Effect of different dietary levels of protein on fat deposition in broilers divergently selected for high or low abdominal adipose tissue1

“…The skeleton is known to be an important lipogenic site in the fowl (Nir and Lin, 1982;Calabotta et al, 1983). The higher fat content in the tibia bone of the LF line has been confirmed in other studies (unpublished observations) and suggests that lipogenesis in the skeleton of LF birds is higher, or that the mobilisation from this site to the adipose tissues is lower compared with the HF birds.…”

Removal of residual yolk at hatch influences food choice and feeding activity in lines of chickens selected for high or low juvenile body weight

“…Nitsan et al (1991 ) GIT would be inefficient in digesting it during the first few days after hatch. In intact chickens, Calabotta et al (1983Calabotta et al ( , 1985 (Nitsan et al, 1991;Nir and Levanon, 1993) and the chick had changed from primarily a lipidbased to a carbohydrate-based metabolism with external food sources (Duke, 1984 …”