To determine whether non-fibrous carbohydrate (NFC) supplementation improves fiber digestibility and microbial protein synthesis, 18 Corriedale ewes with a fixed intake level (40 g dry matter (DM)/kg BW0.75) were assigned to three (n = 6) diets: F = 100% fresh temperate forage, FG = 70% forage + 30% barley grain and FGM = 70% forage + 15% barley grain + 15% molasses-based product (MBP, Kalori 3000). Two experimental periods were carried out, with late (P1) and early (P2) vegetative stage forage.
View Article and Find Full Text PDFTo test the effect of insulin on renal perfusion and the participation of NO and PG as mediators of this response, renal blood flow (RBF) was measured in sheep (n = 8) implanted with ultrasonic flow probes around renal arteries and with a systemic arterial pressure (SAP, n = 4) telemetry device. Three protocols were performed: 1) RBF and SAP were recorded (0800 to 1800 h) in fed and fasted sheep, with the latter receiving intravenous (i.v.
View Article and Find Full Text PDFTo assess the roles of feeding behavior (eating and rumination) and systemic arterial pressure (SAP) on determination of the circadian rhythm of renal blood flow (RBF), 20 sheep fitted with ultrasonic flow-metering probes around both renal arteries and a submandibular balloon to monitor jaw movements (6 of them with a telemetry measurement system into the carotid artery for SAP recording), were successively assigned to 6 feeding patterns: once daily in the morning (0900 to 1100 h), afternoon (1700 to 1900 h), or evening (1900 to 2100 h); twice daily at 0900 to 1100 h and 1700 to 1900 h; ad libitum (food renewed each 2 h); and fasting (40 h). All protocols were carried out in autumn-winter, and the fasting pattern was repeated in spring-summer to evaluate the effect of the daylight length on RBF. In the once-daily feeding patterns, a rapid increase in RBF (P < 0.
View Article and Find Full Text PDFThe effect of glucagon on renal haemodynamics in sheep is controversial. In this study we have examined the effects of perfused glucagon on renal blood flow (RBF) in six conscious sheep bilaterally implanted with transit-time ultrasonic flow metering probes around the renal arteries. Glucagon was perfused intravenously over 90 min at doses of 3.
View Article and Find Full Text PDFThe aim of the present study was to compare the amount of microbial N entering the duodenum and the efficiency of N utilisation for microbial protein synthesis in normal (NP, 17.4 g N/d) and low protein (LP, 7.5 g N/d) fed Corriedale sheep.
View Article and Find Full Text PDFMicropuncture studies of late proximal, early and late distal cortical tubules were carried out on kidneys of normal (NP) and low (LP) protein fed sheep in order to investigate the participation of these segments in the urea sparing induced by protein restriction in the diet. A low protein diet induced significant reductions in the fractional (-54%) and total (-84%) urea excretion, revealing an enhanced capacity for urea conservation. Micropuncture data did not show any difference in the proximal tubule functions between both groups of sheep.
View Article and Find Full Text PDFThe effect of eating on glomerular filtration and urine flow was studied in the sheep. Glomerular filtration rate was reduced during eating but the effect disappeared when food was removed. Urine flow showed the same evolution but, after ingestion was stopped, it returned later than glomerular filtration to control values.
View Article and Find Full Text PDF