Water deprivation is associated with regional increases in sympathetic tone, but whether this is mediated by changes in brain stem regulation of sympathetic activity is unknown. Therefore, this study tested the hypothesis that water deprivation increases excitatory amino acid (EAA) drive of the rostral ventrolateral medulla (RVLM), by determining whether bilateral microinjection of kynurenate (...

Radioactive water injected into 10-day-old rats were recovered the following day from their mothers' blood. This transfer of water was nearly eliminated by ligating the injected pups' urethras, a result indicating that mother rats consume their offspring's urine. Preventing urine consumption by ligating urethras of all pups in a litter doubled the plasma volume deficit in dams produced by 24 hr...

Corticosterone (CORT) secretion is influenced by endogenous factors (e.g., physiological status) and environmental stressors (e.g., ambient temperature). Heretofore, the impact of water deprivation on CORT plasma levels has not been thoroughly investigated. However, both baseline CORT and stress-induced CORT are expected to respond to water deprivation not only because of hydric stress per se, ...

Background: The present study examined the possible role of endogenous opioidergic system in effect of food deprivation on formalin-induced nociceptive behaviors in male and female rats. Also, we investigated the effect of food deprivation on the plasma level of beta-endorphin and sex hormones. Methods: Food was withdrawn 48 h prior to performing the formalin test, but water continued to be ava...

Freedom of (prolonged) thirst is considered to be of paramount importance for animal welfare. This emotion normally results from dehydration, which can be measured using physiological indicators. Because no reliable physiological indicator for thirst was available for broilers, we aimed to identify such a measure in this study. This indicator would ideally be integrated into quality control sys...

Three aquaporins (AQP) are present in the membrane of the principal collecting duct cells. On the apical side, the levels of AQP2 protein are increased in response to both arginine vasopressin and water deprivation. However, whether this change parallels changes in the abundance of AQP3 and AQP4 in the basolateral membrane is less well known. This study evaluates the effect of either dehydratio...

Water deprivation-induced thirst is explained by the double-depletion hypothesis, which predicts that dehydration of the two major body fluid compartments, the extracellular and intracellular compartments, activates signals that combine centrally to induce water intake. However, sodium appetite is also elicited by water deprivation. In this brief review, we stress the importance of the water-de...

In this study, two genotypes from the white clover breeding line ‘Syrian selection’, which demonstrates improved survival in summer drought, and two from the white clover cultivar ‘Grasslands Kopu’, a more drought-sensitive cultivar, are compared in terms of their responses to a water deficit. Plants of each genotype were grown in a temperature-controlled glasshouse and a water deficit imposed ...

Two trials were conducted with a total of 12 beef heifers and steers to determine the effect of 48-hr deprivation of feed or water or both on rectal temperature, respiratory and heart rates, electrocardiograph (EKG) patterns, packed cell volume (PCV) and the concentrations of serum sodium, potassium, calcium and magnesium. The same measurements plus the serum concentration of total acid-soluble...