TY - GEN A1 - Paßlack, Nadine A1 - Schmiedchen, Bettina A1 - Raila, Jens A1 - Schweigert, Florian J. A1 - Stumpff, Friederike A1 - Kohn, Barbara A1 - Neumann, Konrad A1 - Zentek, Jürgen T1 - Impact of increasing dietary calcium levels on calcium excretion and vitamin D metabolites in the blood of healthy adult cats T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Background Dietary calcium (Ca) concentrations might affect regulatory pathways within the Ca and vitamin D metabolism and consequently excretory mechanisms. Considering large variations in Ca concentrations of feline diets, the physiological impact on Ca homeostasis has not been evaluated to date. In the present study, diets with increasing concentrations of dicalcium phosphate were offered to ten healthy adult cats (Ca/phosphorus (P): 6.23/6.02, 7.77/7.56, 15.0/12.7, 19.0/17.3, 22.2/19.9, 24.3/21.6 g/kg dry matter). Each feeding period was divided into a 10-day adaptation and an 8-day sampling period in order to collect urine and faeces. On the last day of each feeding period, blood samples were taken. Results Urinary Ca concentrations remained unaffected, but faecal Ca concentrations increased (P < 0.001) with increasing dietary Ca levels. No effect on whole and intact parathyroid hormone levels, fibroblast growth factor 23 and calcitriol concentrations in the blood of the cats were observed. However, the calcitriol precursors 25(OH)D-2 and 25(OH)D-3, which are considered the most useful indicators for the vitamin D status, decreased with higher dietary Ca levels (P = 0.013 and P = 0.033). Increasing dietary levels of dicalcium phosphate revealed an acidifying effect on urinary fasting pH (6.02) and postprandial pH (6.01) (P < 0.001), possibly mediated by an increase of urinary phosphorus (P) concentrations (P < 0.001). Conclusions In conclusion, calcitriol precursors were linearly affected by increasing dietary Ca concentrations. The increase in faecal Ca excretion indicates that Ca homeostasis of cats is mainly regulated in the intestine and not by the kidneys. Long-term studies should investigate the physiological relevance of the acidifying effect observed when feeding diets high in Ca and P. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 542 KW - chronic kidney-disease KW - growth-factor 23 KW - parathyroid-hormone KW - urinary ph KW - phosphorus KW - FGF23 KW - deficiency KW - dogs KW - hypercalciuria KW - secretion Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-411302 SN - 1866-8372 IS - 542 ER - TY - GEN A1 - Brenten, Thomas A1 - Morris, Penelope J. A1 - Salt, Carina A1 - Raila, Jens A1 - Kohn, Barbara A1 - Brunnberg, Leo A1 - Schweigert, Florian J. A1 - Zentek, Jürgen T1 - Energy intake, growth rate and body composition of young Labrador Retrievers and Miniature Schnauzers fed different dietary levels of vitamin A T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Research in rodents has shown that dietary vitamin A reduces body fat by enhancing fat mobilisation and energy utilisation; however, their effects in growing dogs remain unclear. In the present study, we evaluated the development of body weight and body composition and compared observed energy intake with predicted energy intake in forty-nine puppies from two breeds (twenty-four Labrador Retriever (LAB) and twenty-five Miniature Schnauzer (MS)). A total of four different diets with increasing vitamin A content between 5.24 and 104.80 mu mol retinol (5000-100 000 IU vitamin A)/4184 kJ (1000 kcal) metabolisable energy were fed from the age of 8 weeks up to 52 (MS) and 78 weeks (LAB). The daily energy intake was recorded throughout the experimental period. The body condition score was evaluated weekly using a seven-category system, and food allowances were adjusted to maintain optimal body condition. Body composition was assessed at the age of 26 and 52 weeks for both breeds and at the age of 78 weeks for the LAB breed only using dual-energy X-ray absorptiometry. The growth curves of the dogs followed a breed-specific pattern. However, data on energy intake showed considerable variability between the two breeds as well as when compared with predicted energy intake. In conclusion, the data show that energy intakes of puppies particularly during early growth are highly variable; however, the growth pattern and body composition of the LAB and MS breeds are not affected by the intake of vitamin A at levels up to 104.80 mu mol retinol (100 000 IU vitamin A)/4184 kJ (1000 kcal). T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 603 KW - dog growth KW - vitamin A KW - body composition KW - energy intake Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-415681 SN - 1866-8372 IS - 603 ER - TY - GEN A1 - Morris, Penelope J. A1 - Salt, Carina A1 - Raila, Jens A1 - Brenten, Thomas A1 - Kohn, Barbara A1 - Schweigert, Florian J. A1 - Zentek, Jürgen T1 - Safety evaluation of vitamin A in growing dogs T2 - Potsprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The safe upper limit for inclusion of vitamin A in complete diets for growing dogs is uncertain, with the result that current recommendations range from 5.24 to 104.80 mu mol retinol (5000 to 100 000 IU vitamin A)/4184 kJ (1000 kcal) metabolisable energy (ME). The aim of the present study was to determine the effect of feeding four concentrations of vitamin A to puppies from weaning until 1 year of age. A total of forty-nine puppies, of two breeds, Labrador Retriever and Miniature Schnauzer, were randomly assigned to one of four treatment groups. Following weaning at 8 weeks of age, puppies were fed a complete food supplemented with retinyl acetate diluted in vegetable oil and fed at 1ml oil/100 g diet to achieve an intake of 5.24, 13.10, 78.60 and 104.80 mu mol retinol (5000, 12 500, 75 000 and 100 000 IU vitamin A)/4184 kJ (1000 kcal) ME. Fasted blood and urine samples were collected at 8, 10, 12, 14, 16, 20, 26, 36 and 52 weeks of age and analysed for markers of vitamin A metabolism and markers of safety including haematological and biochemical variables, bone-specific alkaline phosphatase, cross-linked carboxyterminal telopeptides of type I collagen and dual-energy X-ray absorptiometry. Clinical examinations were conducted every 4 weeks. Data were analysed by means of a mixed model analysis with Bonferroni corrections for multiple endpoints. There was no effect of vitamin A concentration on any of the parameters, with the exception of total serum retinyl esters, and no effect of dose on the number, type and duration of adverse events. We therefore propose that 104.80 mu mol retinol (100 000 IU vitamin A)/4184 kJ (1000 kcal) is a suitable safe upper limit for use in the formulation of diets designed for puppy growth. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 686 KW - puppies KW - dogs KW - Retinol KW - Retinyl esters KW - vitamin A Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-414929 IS - 686 ER - TY - GEN A1 - Raila, Jens A1 - Rohn, Sascha A1 - Schweigert, Florian J. A1 - Abraham, Getu T1 - Increased antioxidant capacity in the plasma of dogs after a single oral dosage of tocotrienols T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The intestinal absorption of tocotrienols (TCT) in dogs is, to our knowledge, so far unknown. Adult Beagle dogs (n 8) were administered a single oral dosage of a TCT-rich fraction (TRF; 40 mg/kg body weight) containing 32 % a-TCT, 2 % b-TCT, 27 % g-TCT, 14 % d-TCT and 25 % a-tocopherol (a-TCP). Blood was sampled at baseline (fasted), 1, 2, 3, 4, 5, 6, 8 and 12 h after supplementation. Plasma and chylomicron concentrations of TCT and a-TCP were measured at each time point. Plasma TAG were measured enzymatically, and plasma antioxidant capacity was assessed by the Trolox equivalent antioxidant capacity assay. In fasted dogs, levels of TCT were 0·07 ( SD 0·03) mmol/l. Following the administration of the TRF, total plasma TCT peaked at 2 h (7·16 ( SD 3·88) mmol/l; P, 0·01) and remained above baseline levels (0·67 ( SD 0·44) mmol/l; P, 0·01) at 12 h. The TCT response in chylomicrons paralleled the increase in TCT in plasma with a maximum peak (3·49 ( SD 2·06) mmol/l; P, 0·01) at 2 h post-dosage. a-TCP was the major vitamin E detected in plasma and unaffected by TRF supplementation. The Trolox equivalent values increased from 2 h (776 ( SD 51·2) mmol/l) to a maximum at 12 h (1130 ( SD 7·72) mmol/l; P,0·01). The results show that TCT are detected in postprandial plasma of dogs. The increase in antioxidant capacity suggests a potential beneficial role of TCT supplementation in the prevention or treatment of several diseases in dogs. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 571 KW - dogs KW - tocotrienols KW - intestinal absorption KW - antioxidant capacity Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-413085 SN - 1866-8372 IS - 571 ER - TY - GEN A1 - Henze, Andrea A1 - Aumer, Franziska A1 - Grabner, Arthur A1 - Raila, Jens A1 - Schweigert, Florian J. T1 - Genetic differences in the serum proteome of horses, donkeys and mules are detectable by protein profiling T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Although horses and donkeys belong to the same genus, their genetic characteristics probably result in specific proteomes and post-translational modifications (PTM) of proteins. Since PTM can alter protein properties, specific PTM may contribute to species-specific characteristics. Therefore, the aim of the present study was to analyse differences in serum protein profiles of horses and donkeys as well as mules, which combine the genetic backgrounds of both species. Additionally, changes in PTM of the protein transthyretin (TTR) were analysed. Serum protein profiles of each species (five animals per species) were determined using strong anion exchanger ProteinChips (R) (Bio-Rad, Munich, Germany) in combination with surface-enhanced laser desorption ionisation-time of flight MS. The PTM of TTR were analysed subsequently by immunoprecipitation in combination with matrix-assisted laser desorption ionisation-time of flight MS. Protein profiling revealed species-specific differences in the proteome, with some protein peaks present in all three species as well as protein peaks that were unique for donkeys and mules, horses and mules or for horses alone. The molecular weight of TTR of horses and donkeys differed by 30Da, and both species revealed several modified forms of TTR besides the native form. The mass spectra of mules represented a merging of TTR spectra of horses and donkeys. In summary, the present study indicated that there are substantial differences in the proteome of horses and donkeys. Additionally, the results probably indicate that the proteome of mules reveal a higher similarity to donkeys than to horses. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 567 KW - mass spectrometry KW - post-translational modifications KW - proteome KW - species differences Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-412886 SN - 1866-8372 IS - 567 ER -