Institute of Nutritional Physiology Oskar Kellner

Dummerstorf, Germany

Institute of Nutritional Physiology Oskar Kellner

Dummerstorf, Germany

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Casanas M.A.A.,Institute of Nutritional Physiology Oskar Kellner | Schaff C.T.,Institute of Nutritional Physiology Oskar Kellner | Albrecht E.,Institute of Muscle Biology and Growth | Hammon H.M.,Institute of Nutritional Physiology Oskar Kellner | And 4 more authors.
Journal of Dairy Science | Year: 2017

Free fatty acid receptors (FFAR) play significant roles in various physiological processes, including energy metabolism, through interaction with their ligands, fatty acids. To determine whether the receptors FFAR1 and FFAR2 are involved in the regulation of liver metabolism during the peripartal period, we selected 13 German Holstein multiparous dairy cows and grouped them as high β-hydroxybutyrate (H-BHB; n = 8) or low β-hydroxybutyrate (L-BHB; n = 5) according to their individual maximum plasma BHB concentration observed within wk 2 or 3 postpartum (H-BHB: >1 mmol/L and L-BHB: <0.77 mmol/L). The selected cows had a milk yield of more than 10,000 kg/305 d during a previous lactation. The cows were fed a total mixed ration according to their requirements during the far-off dry period [5.9 MJ of net energy for lactation (NEL)/kg of dry matter (DM), crude protein (CP) 126 g/kg of DM], close-up dry period (6.5 MJ of NEL/kg of DM, CP 137 g/kg of DM), and lactation (7 MJ of NEL/kg of DM, CP 163 g/kg of DM). Blood samples were taken weekly, from d -34 to d 40 relative to parturition. Liver biopsies were taken on d -34, -17, 3, 18, and 30 relative to parturition and at slaughter (d 40). The protein abundance of FFAR1 was lower during the whole peripartal period in the H-BHB group. The abundance of FFAR2 increased over time and tended to be higher in H-BHB cows. The abundance of FFAR1 might be associated with imbalances of liver metabolism in peripartal dairy cows. © 2017 American Dairy Science Association.


PubMed | Institute of Nutritional Physiology Oskar Kellner, Institute of Muscle Biology and Growth and Leibniz Institute for Farm Animal Biology
Type: | Journal: Journal of dairy science | Year: 2017

Free fatty acid receptors (FFAR) play significant roles in various physiological processes, including energy metabolism, through interaction with their ligands, fatty acids. To determine whether the receptors FFAR1 and FFAR2 are involved in the regulation of liver metabolism during the peripartal period, we selected 13 German Holstein multiparous dairy cows and grouped them as high -hydroxybutyrate (H-BHB; n = 8) or low -hydroxybutyrate (L-BHB; n = 5) according to their individual maximum plasma BHB concentration observed within wk 2 or 3 postpartum (H-BHB: >1 mmol/L and L-BHB: <0.77 mmol/L). The selected cows had a milk yield of more than 10,000 kg/305 d during a previous lactation. The cows were fed a total mixed ration according to their requirements during the far-off dry period [5.9 MJ of net energy for lactation (NE


Hamada M.,Leibniz Institute for Farm Animal Biology | Hamada M.,Sadat City University | Albrecht E.,Leibniz Institute for Farm Animal Biology | El Bagory A.-R.,Sadat City University | And 4 more authors.
Livestock Science | Year: 2015

The presented study investigated changes of fat cell and muscle fibre size, and muscle fibre type composition around first parturition in cows with a combined beef and dairy genetic background. In contrast to high-merit dairy cows, these cows can serve as a model for beef cows because of the very low milk production level. Fifty heifers used in this experiment were F2 offspring originating from mating Charolais bulls to German Holstein cows and a following intercross of F1 individuals. They were assigned to 3 groups according to their lactation performance, namely high lactating (HL), low lactating long (LLL; duration of first lactation at least 100 days), and low lactation short (LLS; duration of first lactation shorter than 100 days). Biopsy samples were taken from semitendinosus muscle (MST) and subcutaneous fat (SCF) at three time points, 10 days before first parturition, 30 and 100 days after calving. These samples were investigated by histology and computer image analysis for muscle fibre profile, as well as intramuscular and subcutaneous fat cell size to estimate the impact of lactation on body reserves. Most cows continued growth and gained weight during lactation. Continuous tissue accretion was indicated on the cellular level by an increase in intramuscular fat cell size. Subcutaneous fat cells were larger in low lactating cows with a short lactation period. There were no morphological signs of fat mobilization from fat cells. There was also no protein mobilization indicated by changes in muscle fibre size. However, the increase in percentage of fast, glycolytic muscle fibres indicated alterations in muscle metabolism during transition from late pregnancy to early lactation. Cows remained obviously in a positive energy balance in this study and continued tissue accretion during lactation. This was reflected on the cellular level in skeletal muscle and subcutaneous fat. © 2015 Elsevier B.V.


Schaff C.T.,Institute of Nutritional Physiology Oskar Kellner | Rohrbeck D.,Institute of Nutritional Physiology Oskar Kellner | Steinhoff-Wagner J.,Institute of Nutritional Physiology Oskar Kellner | Kanitz E.,Leibniz Institute for Farm Animal Biology | And 3 more authors.
Journal of Dairy Science | Year: 2015

Catecholamines and glucocorticoids are involved in fetal maturation of organ systems to prepare the fetus for extrauterine life. Calves, especially when born preterm, depend on function of the adrenergic system and the glucocorticoid axis to adapt energy metabolism for the neonatal period. We tested the hypothesis that hepatic glucocorticoid and α1- and β2-adrenergic receptors in neonatal calves are involved in adaptation of energy metabolism around birth and that respective binding capacities depend on stage of maturation during the neonatal period. Calves (n=7 per group) were delivered by section preterm (PT, 9d before term) or were born at term (full-term, FT; spontaneous vaginal delivery), or spontaneously born and fed colostrum for 4d (FTC). Blood samples were taken immediately after birth and before and 2h after feeding at 24h after birth (PT, FT) or on d 4 of life (FTC) to determine metabolic and endocrine changes. After slaughter at 26h after birth (PT, FT) or on d 4 of life (FTC), liver tissue was obtained to measure hepatic binding capacity of glucocorticoid and α1- and β2-adrenergic receptors. Maximal binding capacity and binding affinity were calculated by saturation binding assays using [3H]-prazosin and [3H]-CGP-12177 for determination of α1- and β2-adrenergic receptors, respectively, and [3H]-dexamethasone for determination of glucocorticoid receptor in liver. Additional liver samples were taken to measure mRNA abundance of glucocorticoid and α1- and β2-adrenergic receptors, of key enzymes and factors related to hepatic lipid metabolism, and of insulin-like growth factor 1 (IGF1). Plasma concentrations of β-hydroxybutyrate and leptin changed with time, and leptin concentrations were affected by stage of maturation. The binding capacities for hepatic glucocorticoid and β2-adrenergic receptors as well as gene expression of IGF1 were greater in FTC than in FT and PT, and binding affinity for β2-adrenergic receptor was lowest in PT. The binding capacity of hepatic α1-adrenergic receptor was greatest in FTC and greater in FT than in PT. The binding capacities of glucocorticoid and α1-adrenergic receptors were mainly related to variables of glucose and lipid metabolism. In conclusion, our results indicate dependence of hepatic glucocorticoid and adrenergic receptors on stage of maturation in neonatal calves and emphasize the association of α1-adrenergic receptor and glucocorticoid receptor with neonatal glucose and lipid metabolism. © 2015 American Dairy Science Association.


PubMed | Institute of Nutritional Physiology Oskar Kellner, University of Bonn, University of Bern and Leibniz Institute for Farm Animal Biology
Type: Journal Article | Journal: Journal of dairy science | Year: 2015

Catecholamines and glucocorticoids are involved in fetal maturation of organ systems to prepare the fetus for extrauterine life. Calves, especially when born preterm, depend on function of the adrenergic system and the glucocorticoid axis to adapt energy metabolism for the neonatal period. We tested the hypothesis that hepatic glucocorticoid and 1- and 2-adrenergic receptors in neonatal calves are involved in adaptation of energy metabolism around birth and that respective binding capacities depend on stage of maturation during the neonatal period. Calves (n=7 per group) were delivered by section preterm (PT, 9d before term) or were born at term (full-term, FT; spontaneous vaginal delivery), or spontaneously born and fed colostrum for 4d (FTC). Blood samples were taken immediately after birth and before and 2h after feeding at 24h after birth (PT, FT) or on d 4 of life (FTC) to determine metabolic and endocrine changes. After slaughter at 26h after birth (PT, FT) or on d 4 of life (FTC), liver tissue was obtained to measure hepatic binding capacity of glucocorticoid and 1- and 2-adrenergic receptors. Maximal binding capacity and binding affinity were calculated by saturation binding assays using [(3)H]-prazosin and [(3)H]-CGP-12177 for determination of 1- and 2-adrenergic receptors, respectively, and [(3)H]-dexamethasone for determination of glucocorticoid receptor in liver. Additional liver samples were taken to measure mRNA abundance of glucocorticoid and 1- and 2-adrenergic receptors, of key enzymes and factors related to hepatic lipid metabolism, and of insulin-like growth factor 1 (IGF1). Plasma concentrations of -hydroxybutyrate and leptin changed with time, and leptin concentrations were affected by stage of maturation. The binding capacities for hepatic glucocorticoid and 2-adrenergic receptors as well as gene expression of IGF1 were greater in FTC than in FT and PT, and binding affinity for 2-adrenergic receptor was lowest in PT. The binding capacity of hepatic 1-adrenergic receptor was greatest in FTC and greater in FT than in PT. The binding capacities of glucocorticoid and 1-adrenergic receptors were mainly related to variables of glucose and lipid metabolism. In conclusion, our results indicate dependence of hepatic glucocorticoid and adrenergic receptors on stage of maturation in neonatal calves and emphasize the association of 1-adrenergic receptor and glucocorticoid receptor with neonatal glucose and lipid metabolism.


PubMed | Institute of Nutritional Physiology Oskar Kellner, University of Bonn, University of Bern and Leibniz Institute for Farm Animal Biology
Type: Journal Article | Journal: Journal of dairy science | Year: 2016

Dairy cows undergo significant metabolic and endocrine changes during the transition from pregnancy to lactation, and impaired insulin action influences nutrient partitioning toward the fetus and the mammary gland. Because impaired insulin action during transition is thought to be related to elevated body condition and body fat mobilization, we hypothesized that over-conditioned cows with excessive body fat mobilization around calving may have impaired insulin metabolism compared with cows with low fat mobilization. Nineteen dairy cows were grouped according to their average concentration of total liver fat (LFC) after calving in low [LLFC; LFC <24% total fat/dry matter (DM); n=9] and high (HLFC; LFC >24.4% total fat/DM; n=10) fat-mobilizing cows. Blood samples were taken from wk 7 antepartum (ap) to wk 5 postpartum (pp) to determine plasma concentrations of glucose, insulin, glucagon, and adiponectin. We applied euglycemic-hyperinsulinemic (EGHIC) and hyperglycemic clamps (HGC) in wk 5 ap and wk 3 pp to measure insulin responsiveness in peripheral tissue and pancreatic insulin secretion during the transition period. Before and during the pp EGHIC, [(13)C6] glucose was infused to determine the rate of glucose appearance (GlucRa) and glucose oxidation (GOx). Body condition, back fat thickness, and energy-corrected milk were greater, but energy balance was lower in HLFC than in LLFC. Plasma concentrations of glucose, insulin, glucagon, and adiponectin decreased at calving, and this was followed by an immediate increase of glucagon and adiponectin after calving. Insulin concentrations ap were higher in HLFC than in LLFC cows, but the EGHIC indicated no differences in peripheral insulin responsiveness among cows ap and pp. However, GlucRa and GOx:GlucRa during the pp EGHIC were greater in HLFC than in LLFC cows. During HGC, pancreatic insulin secretion was lower, but the glucose infusion rate was higher pp than ap in both groups. Plasma concentrations of nonesterified fatty acids decreased during HGC and EGHIC, but in both clamps, pp nonesterified fatty acid concentrations did not reach the ap levels. The study demonstrated a minor influence of different degrees of body fat mobilization on insulin metabolism in cows during the transition period. The distinct decrease in the glucose-dependent release of insulin pp is the most striking finding that explains the impaired insulin action after calving, but does not explain differences in body fat mobilization between HLFC and LLFC cows.


PubMed | Institute of Nutritional Physiology Oskar Kellner
Type: Journal Article | Journal: Journal of dairy science | Year: 2013

Quercetin has been shown to be a potent antioxidant, acts hepatoprotectively, and affects glucose and lipid metabolism in monogastrics. If this is also true in ruminants, quercetin could be beneficial in periparturient high-yielding dairy cows by ameliorating the negative effects of free radical formation and reducing the severity of liver lipidosis and ketosis. In a first attempt to evaluate effects of a long-term quercetin treatment, we intraduodenally administered twice daily 18 mg of quercetin (Q)/kg of body weight to 5 late-lactation (215d in milk) dairy cows over a period of 28 d. Frequent blood samples were taken before and during administration to determine plasma concentrations of flavonols and metabolites. Before and after 1 and 4 wk of Q administration, glycogen and fat content as well as mRNA expression of selected genes were measured in liver biopsies. Furthermore, euglycemic, hyperinsulinemic, and hyperglycemic clamp studies were conducted before and after 2 wk of Q administration. During the experiment, dry matter intake and most other zootechnical data remained unchanged. Milk protein content was increased in wk 2 and 4 of Q administration compared with basal values, whereas fat and lactose contents of milk remained unchanged. Plasma nonesterified fatty acids, -glutamyl transferase, cholesterol, glutamate dehydrogenase, triglyceride, and albumin concentrations, as well as liver fat and glycogen concentrations, were not affected by Q supplementation. Plasma glucose and -hydroxybutyrate concentrations in plasma decreased and increased, respectively, under the influence of quercetin. During hyperglycemic clamp conditions, the relative increase of plasma insulin was higher after 2 wk of Q administration, and a tendency for an increased rQUICKI (revised quantitative insulin sensitivity check index) was observed. The relative mRNA expression levels of selected genes related to glucose metabolism, fat metabolism, and antioxidative status were not altered after 1 or 4 wk of Q supplementation. In conclusion, the effects on insulin release and sensitivity support the assumption that administration of Q could have positive effects on the metabolic adaption of high-yielding cows to early lactation. The increase of milk protein content in response to Q supplementation needs to be verified.

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