Daily variation in blood enzymes and metabolites in ewes under three levels of feed intake

Abstract

. 1999. Daily variation in blood enzymes and metabolites in ewes under three levels of feed intake. Can. J. Anim. Sci. 79: 157-164. Daily variations in the concentration of albumin, creatinine, non-esterified fatty acids, globulins, glucose, total lipids, total protein, triglycerides, urea, β-hydroxybutyrate, and in the activity of alkaline phosphatases, aspartate aminotransferase, glucose-6-phosphate dehydrogenase, glutamate dehydrogenase, isocitrate dehydrogenase and pyruvate kinase were evaluated in the serum or plasma of ewes fed 30, 100 and 200% of theoretical maintenance energy requirements. A daily profile was observed in almost all variables, which may be of importance when interpreting data for these blood indicators. Daily variations were found even for albumin and total protein serum concentrations, showing a significant decrease of their levels after the meal. In order to maximize the diagnostic value of these indicators, the most suitable times for blood collection seem to be 16 h after the meal and (or) just before the meal. Collection 16 h after the meal apparently allows the characterisation of a relatively steady metabolic state, intermediate between the effects of food intake and the final phase of the intensification of body reserve mobilization. Collection just before the meal will give a good indication of the level of activity of those mobilization mechanisms. La variation quotidienne d'albumine, créatinine, acides gras non estérifiés, globulines, glucose, lipides totaux, protéines totales, triglycérides, urée, β-hydroxybutyrate, phosphatases alcalines, aspartate aminotransférase, glucose-6-phosphate déshydrogénase, glutamate déshydrogénase, isocitrate déshydrogénase, pyruvate kinase fut évaluée dans le sérum ou le plasma des brebis ayant reçu dans l'alimentation 30 %, 100 % et 200 % des besoins énergétiques d'entretien théoriques. Nous avons observé, dans presque toutes les variables, un type de profile quotidien susceptible d'influencer l'interprétation de ces indicateurs sanguins. Des variations quotidiennes ont été trouvées même pour des concentrations d'albumine et de protéine totale dans le sérum, montrant une diminution significative de leurs niveaux après le repas. Pour maximiser la valeur diagnostique de ces indicateurs, les moments les plus appropriés pour faire la prise de sang semblent être 16 heures après le repas et (ou) juste avant le repas. La prise de sang 16 heures après le repas permet de caractériser un état métabolique relativement constant, intermédiaire entre les effets proches de l'ingestion et la phase finale d'intensification de la mobilisation des réserves corporelles. La prise de sang juste avant le repas donne une bonne image du niveau d'activité de ces mécanismes de mobilisation.

Pre-analytical factors affecting the results of laboratory blood analyses in farm animal veterinary diagnostics

“…Moreover, plasma urea varies throughout the day in relation to the time of feeding (Gustafsson and Palmquist, 1993;Rodriguez et al, 1997;Piccione et al, 2006). In sheep, Caldeira et al (1999) published variation of most routine analytes depending on feeding time and level of feed intake; however, in this study, ewes had access to food just once a day, which may not be comparable with ordinary conditions, for example, at pasture.…”

Haematological and biochemical parameters in Churra-da-Terra-Quente ewes from the northeast of Portugal

“…If the filtering process of the kidney is deficient, blood levels rise. Thus it constitutes a fundamental parameter in the evaluation of the kidney function since it is associated with creatinine metabolism and it is also involved in the storage and stabilization of elevated energy phosphate groups related with muscle energetic metabolism (Finco, 1997), and its serum level is not significantly affected by the ruminant diet (Finco, 1997;Caldeira et al, 1999;Sakkinen et al, 2001) or by alterations in the hepatic function or by the urea cycle (Finco, 1997). Considering the ruminant, it is important to notice that uremia might present itself diminished in a protein deficit situation, since it is highly influenced by the type of diet and also by the timing of the blood sample collection regarding the last meal (Caldeira et al, 1999(Caldeira et al, , 2007.…”

Metabolismo energético, proteico e mineral de ovelhas Santa Inês hígidas e com mastite subclínica

“…Estes resultados ratificam o não comprometimento desta variável pela dieta, conforme relatado por Caldeira et al (1999). Diferentemente deste estudo em ovelhas, Bertoni (1996) e Chiofalo et al (2009) observaram em vacas e cabras leiteiras, respectivamente, elevação nos valores da creatinina nos momentos próximo ao parto, atribuindo este achado à mobilização de proteína muscular com o propósito de produzir energia no início da lactação.…”