Abstract
1. Male birds of a laying strain had permanent catheters introduced into the hepatic portal vein via the coccygeo‐mesenteric vein. 2. Infusions of 5 ml of 40, 100 or 150 g glucose/1 solution over 2 min caused a non‐significant depression of food intake compared with a 9 g NaCl/1 control solution. 3. Infusions of a range of isotonic glucose solutions (0 to 60 g glucose/1, 300 mosm) at 1.4 ml/min over 3 h caused food intake depression within the 3‐h period (P<0.01) proportional to the logarithm of the dose. 4. This effect was not observed when 60 g glucose/1 was infused at the above rates into the jugular vein. 5. Starvation of the bird for 21 h accentuated the depressive effect of glucose load on food intake, especially when birds were not given food until after the 3‐h infusion. 6. The infusion of solutions of sodium chloride (1.0 to 13.0 g/1, 33 to 433 mosmoles/kg) at. 1.4 ml/min over 3 h stimulated food intake within the range of 3 to 7 g NaCl/1 (100 to 233 mosm) but suppressed intake outside this range. This can be interpreted as a possible interaction with water intake control. 7. Infusion of 20 ml of glucose solution (0, 18 or 54 g/l) over 5 min into the crop and 0, 3.75 or 60 g glucose/1 at 1.4 ml/min over 3 h into the hepatic portal vein, caused an additive, linear depression of food intake.