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Broiler breeder pullets were divided into two groups at 21 wk of age. One group was given free access to feed (ad libitum) and the other fed a limited amount of feed (restricted). At 22 wk, all birds were photostimulated and maintained throughout an egg-laying cycle ending at 36 wk. Samples of liver and abdominal fat pad were collected just before photostimulation (prelight), after photostimulation at first egg and at peak egg production (plateau). Hepatic expression of sterol regulatory element binding protein-1, ATP-citrate lyase, fatty acid synthase, malic enzyme, acetyl-CoA carboxylase and stearoyl-CoA ([DELTA]9) desaturase 1 genes in ad libitum birds declined from their highest levels just before photostimulation as the birds came into and maintained egg production. In contrast, the restricted birds had significant (P < 0.05) increases in the expression of these genes after photostimulation at first egg with a subsequent decline as they reached peak egg production. Hepatic expression of fatty acid binding protein, VLDL apolipoprotein (apoVLDL-II) and apoB genes increased significantly (P < 0.05) in both ad libitum and restricted breeders after photostimulation, whereas apoA1 gene expression declined during this time. Abdominal fat pad weights were significantly (P < 0.05) higher in the ad libitum compared with restricted birds after photostimulation. Lipoprotein lipase in this tissue showed a pattern of expression similar to that observed for the hepatic lipogenic enzyme genes. In conclusion, feed restriction during the pullet-to-breeder transition period significantly (P < 0.05) altered hepatic lipogenic gene expression in broiler breeders. KEY WORDS: * gene expression * lipid metabolism * lipogenesis * mRNA * chickens

The presence of a leptin homolog in liver and adipose tissues of broiler chickens was determined. Leptin expression was also found in chicken embryonic liver and yolk sac. The influences of hormone treatment on leptin expression in chickens were also studied. Leptin expression in the liver was enhanced by insulin and dexamethasone and reduced by glucagon and estrogen. There was no induction of leptin expression in adipose tissue by any treatment, while only estrogen reduced adipose expression.

Insulin-like growth factor-I and -II are important multifunctional polypeptides that interact with membrane-bound receptors as well as soluble binding proteins. The biological actions of these hormones are multifaceted and dependent to a large extent on binding protein interactions. Some unique differences in insulin-like growth factor physiology and biochemistry are evident between mammalian and avian species. These include amino acid compositional and significant receptor differences as well as binding protein status. The biological response to both growth factors is different in birds. A greater proportion of the insulin-like growth factors exists in plasma as free peptide compared with the situation in mammals. This review is a brief summary of our knowledge of insulin-like growth factor physiology in domestic fowl. KEY WORDS: chickens; turkeys; metabolism; hormone

Explores the conflict between education and market goals. Observes that free enterprise differs in goals, motivation, methods, and standards of excellence. Argues that the conflict between the two sets of values is a crisis that is going unnoticed. Suggests that education can lift the market system and serve its needs for literate and numerate workers. (DK)

This study examined the effects of dietary fat on the fatty acid composition of liver and bone, and on the concentration of insulin-like growth factor-I (IGF-I) in liver and bone, as well as the relationship of these factors to bone metabolism. Day-old male broiler chicks were given a semipurified diet containing one of four lipid sources: soybean oil (SBO), butter + corn oil (BC), margarine + corn oil (MAC), or menhaden oil + corn oil (MEC) at 70 g/kg of the diet. At 21 and 42 d of age, chicks fed MEC had the highest concentration of (n-3) fatty acids [20:5(n-3), 22:5(n-3) and 22:6(n-3)] in polar and neutral lipids of cortical bone but the lowest amount of 20:4(n-6) in polar lipids. Diets containing t-18:1 fatty acids (MAC and BC) resulted in t18:1 accumulation in bone and liver. Bone IGF-I concentration increased from 21 to 42 d in chicks given the SBO and BC diets. Tibial periosteal bone formation rate (BFR) was higher in chicks given BC compared with those consuming SBO and MEC at 21 d. The higher BFR and concentrations of hexosamine in serum and IGF-I in cartilage, but lower 20:4(n-6) content in bone polar lipids in chicks given BC compared with those given SBO suggest that BC optimized bone formation by altering the production of bone growth factors. A second study confirmed that dietary butter fat lowered ex vivo prostaglandin [E.sub.2] production and increased trabecular BFR in chick tibia. These studies showed that dietary fat altered BFR perhaps by controlling the production of local regulatory factors in bone. KEY WORDS: * lipids * bone * prostaglandin [E.sub.2] * insulin-like growth factor-I * chicks

The article begins with an overview of the historic moment of 'the end of the Cold War', and of the paradoxically deepening moral, social, and environmental problems posed by the military system. It demonstrates that historical and contemporary analyses of defence and war have dogmatically presupposed the military paradigm, and have therefore failed to recognize the self-reproducing structure of covert premisses and inferences upon which it rests. In laying bare this underlying system of unreason, the analysis demonstrates that the military paradigm's ultimately self-contradictory concepts of 'security' and 'defence' repose on unstated interests of social and political rule. Proposing new distinctions between pathological and life-enabling forms of war, and between guilty and innocent combatants, the argument develops alternative, non-military principles of war to guide rational and moral agency