Hunger and thirst have distinct goals but control similar ingestive behaviors, and little is known about neural processes that are shared between these behavioral states. We identify glutamatergic neurons in the peri-locus coeruleus (periLCⱽᴳᴸᵁᵀ² neurons) as a polysynaptic convergence node from separate energy-sensitive and hydration-sensitive cell populations. We develop methods for stable hindbrain calcium imaging in free-moving mice, which show that periLCⱽᴳᴸᵁᵀ² neurons are tuned to ingestive behaviors and respond similarly to food or water consumption. PeriLCⱽᴳᴸᵁᵀ² neurons are scalably inhibited by palatability and homeostatic need during consumption. Inhibition of periLCⱽᴳᴸᵁᵀ² neurons is rewarding and increases consumption by enhancing palatability and prolonging ingestion duration. These properties comprise a double-negative feedback relationship that sustains food or water consumption without affecting food- or water-seeking. PeriLCⱽᴳᴸᵁᵀ² neurons are a hub between hunger and thirst that specifically controls motivation for food and water ingestion, which is a factor that contributes to hedonic overeating and obesity.

1. The effects on food intake and weight gain of offering broiler chickens (2 to 7 weeks of age) dry food, wet food, wet food containing whey, whey as drinking liquid and combinations of two of these were studied in 5 experiments. 2. Wet feed generally improved both weight gain and feed efficiencies significantly. Feeding whey also improved weight gain and feed conversion efficiency, but whey offered as a drinking fluid had an adverse effect on broiler performance. 3. When whey was offered both as drinking liquid and added to the food it had a deleterious effect. 4. When whey was offered from 4 or 6 weeks of age, it had a better effect than when offered from 2 weeks of age. 5. There was better performance when whey in the drinking water was diluted and/or offered on alternate days or half-days. 6. Broilers allowed to choose between wet and dry feed when water was freely available chose mostly dry feed; in the absence of drinking water they chose mostly wet food. Birds offered water and liquid whey avoided whey completely. 7. It is concluded that whey can be used in diets for broiler chickens by incorporating it in the food as long as drinking water is offered ad libitum. Whey may be offered as a drink if the food is mixed with 1.8 times its weight of water but it is better to dilute the whey with an equal volume of water whether it is added to food or given as drink. Good results can also be obtained when undiluted whey is offered alternately with water, either in half-day or full-day periods.