U Hennig

Leibniz Institute for Farm Animal Biology, Dummerstorf, Mecklenburg-Vorpommern, Germany

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Publications (88)107.53 Total impact

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    ABSTRACT: Inadequate maternal nutrition during gestation may cause an adverse environment for the fetus leading to alterations of the hypothalamic-pituitary-adrenal (HPA) and sympatho-adrenomedullary (SAM) systems later in life. In the present study, we investigated the effects of diets with low and high protein:carbohydrate ratios on cortisol levels of pregnant gilts as well as the long-term effects on the function of the HPA and SAM axes in their offspring. Throughout gestation, 33 German Landrace gilts were fed high (HP, 30 %), low (LP, 6.5 %) or adequate (AP, 12.1 %) protein diets, which were made isocaloric by adjusting the carbohydrate content. The salivary cortisol levels of the sows were measured in the course of the gestation period. The offspring were cross-fostered, and the plasma cortisol and catecholamine levels of the offspring were determined on postnatal days (PND) 1 and 27 and under specific challenging conditions: after weaning (PND 29) and after ACTH and insulin challenges (PND 68 and 70, respectively). Glucocorticoid receptor (GR) binding and neurotransmitter concentrations were measured in stress-related brain regions, and histological analyses of the adrenal were performed. Maternal salivary cortisol levels increased throughout gestation (P < 0.001) and the LP gilts had higher salivary cortisol compared to the AP and HP gilts (P < 0.05). No differences between diets were found for cortisol, corticosteroid-binding globulin, and catecholamine concentrations in plasma and for GR binding in hippocampus and hypothalamus in piglets at PND 1 and 27. However, the cortisol response to weaning was increased in LP piglets (P < 0.05), and in HP offspring the basal plasma noradrenaline levels were increased (P < 0.05). The cortisol response to the ACTH and the insulin challenge did not differ between diets. On PND 81, an increased adrenal medulla area was observed in LP offspring compared to the AP offspring (P < 0.05). Our results show that maternal diets with aberrant protein:carbohydrate ratios during gestation have moderate long-term effects on the function of the HPA and SAM system in the offspring, which indicates that pigs show a considerable plasticity to cope with maternal malnutrition.
    Journal of Animal Science 03/2013; · 1.92 Impact Factor
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    ABSTRACT: A high protein-low-carbohydrate diet during pregnancy can cause intra-uterine growth restriction. However, its impact during pregnancy on maternal, umbilical and fetal plasma amino acid (AA) profiles is unknown. A maternal high-protein (30 %)-low-carbohydrate (HP-LC) diet was compared with isoenergetic standard (12·1 % crude protein; ST) and low-protein (6·5 %)-high-carbohydrate (LP-HC) diets fed to nulliparous pregnant sows to examine changes in AA concentrations in maternal, venous and arterial umbilical and fetal plasma in mid and late pregnancy. At 64 and 94 days of pregnancy (dp), sows underwent Caesarean section, and maternal, umbilical and fetal plasma samples were collected. The HP-LC diet mainly affected maternal plasma AA concentrations. Plasma concentrations of Ile and Val were increased and those of Ala, Glu and Gly were decreased (P ≤ 0·05) in HP-LC compared with ST sows at 64 and 94 dp. The LP-HC diet decreased fetal plasma Glu concentration compared with the ST diet at 94 dp. Substantial AA catabolism was reflected by increased (P ≤ 0·05) maternal and fetal plasma urea concentrations with the HP-LC compared with the ST and LP-HC diets at 94 dp. Fractional placental extraction of Val was higher whereas those of Ala, Gln and Glu were lower in the HP-LC compared with the ST sows at 64 and 94 dp (P ≤ 0·05). Reduced fetal mass at 94 dp was accompanied by reduced fetal extraction of Lys and Pro in the HP-LC group (P ≤ 0·05). In conclusion, a maternal HP-LC diet during pregnancy altered maternal plasma composition of many AA and modified placental AA extraction to compensate for imbalanced maternal nutrient intake.
    The British journal of nutrition 03/2012; · 3.45 Impact Factor
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    ABSTRACT: High and low protein diets fed to pregnant adolescent sows led to intrauterine growth retardation (IUGR). To explore underlying mechanisms, sow plasma metabolite and hormone concentrations were analyzed during different pregnancy stages and correlated with litter weight (LW) at birth, sow body weight and back fat thickness. Sows were fed diets with low (6.5%, LP), adequate (12.1%, AP), and high (30%, HP) protein levels, made isoenergetic by adjusted carbohydrate content. At -5, 24, 66, and 108 days post coitum (dpc) fasted blood was collected. At 92 dpc, diurnal metabolic profiles were determined. Fasted serum urea and plasma glucagon were higher due to the HP diet. High density lipoprotein cholesterol (HDLC), %HDLC and cortisol were reduced in HP compared with AP sows. Lowest concentrations were observed for serum urea and protein, plasma insulin-like growth factor-I, low density lipoprotein cholesterol, and progesterone in LP compared with AP and HP sows. Fasted plasma glucose, insulin and leptin concentrations were unchanged. Diurnal metabolic profiles showed lower glucose in HP sows whereas non-esterified fatty acids (NEFA) concentrations were higher in HP compared with AP and LP sows. In HP and LP sows, urea concentrations were 300% and 60% of AP sows, respectively. Plasma total cholesterol was higher in LP than in AP and HP sows. In AP sows, LW correlated positively with insulin and insulin/glucose and negatively with glucagon/insulin at 66 dpc, whereas in HP sows LW associated positively with NEFA. In conclusion, IUGR in sows fed high protein:low carbohydrate diet was probably due to glucose and energy deficit whereas in sows with low protein:high carbohydrate diet it was possibly a response to a deficit of indispensable amino acids which impaired lipoprotein metabolism and favored maternal lipid disposal.
    PLoS ONE 02/2012; 7(2):e31390. · 3.53 Impact Factor
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    ABSTRACT: The aim of this study was to investigate whether dietary protein intake during gestation less than or greater than recommendations affects gilts growth and body composition, gestation outcome, and colostrum composition. German Landrace gilts were fed gestation diets (13.7 MJ of ME/kg) containing a low (n = 18; LP, 6.5% CP), an adequate (n = 20; AP, 12.1%), or a high (n = 16; HP, 30%) protein content corresponding to a protein:carbohydrate ratio of 1:10.4, 1:5, and 1:1.3, respectively, from mating until farrowing. Gilts were inseminated by semen of pure German Landrace boars and induced to farrow at 114 d postcoitum (dpc; Exp. 1). Energy and protein intake during gestation were 33.3, 34.4, and 35.8 MJ of ME/d (P < 0.001) and 160, 328, and 768 g/d, respectively, in LP, AP, and HP gilts (P < 0.001). From insemination to 109 dpc, BW gain was least in LP (42.1 kg), intermediate in HP (63.1 kg), and greatest in AP gilts (68.3 kg), whereas increase of backfat thickness was least in gilts fed the HP diet compared with LP and AP diets (3.8, 5.1, 5.0 mm; P = 0.01). Litter size, % stillborn piglets, and mummies were unaffected (P > 0.28) by the gestation diet. Total litter weight tended to be less in the offspring of LP and HP gilts (14.67, 13.77 vs. 15.96 kg; P = 0.07), and the percentage of male piglets was greater in litters of HP gilts (59.4%; P < 0.01). In piglets originating from LP and HP gilts, individual birth weight was less (1.20, 1.21 vs. 1.40 kg; P = 0.001) and birth weight/crown-rump length ratio was reduced (45.3, 46.4 vs. 50.7 g/cm; P = 0.003). Colostrum fat (7.8, 7.4 vs. 8.1%) and lactose concentrations (2.2, 2.1 vs. 2.6%) tended to be reduced in LP and HP gilts (P = 0.10). In Exp. 2, 28 gilts (LP, 10; AP, 9; HP, 9) were treated as in Exp. 1 but slaughtered at 64 dpc. At 64 dpc, LP gilts were 7% lighter than AP gilts (P = 0.03), whereas HP gilts were similar to AP gilts. Body composition was markedly altered in response to LP and HP feeding with less lean (P < 0.01) and greater fat content (P = 0.02 to 0.04) in LP and less fat content (P = 0.02 to 0.04) in HP gilts. Fetal litter weight and number, and embryonic survival at 64 dpc were not affected by the diets. These results indicated that gestation diets containing protein at 50 and 250% of recommendations and differing in protein:carbohydrate ratio led to marked changes in protein and fat metabolism in gilts resulting in fetal growth retardation of 15%, which mainly occurred during the second half of gestation.
    Journal of Animal Science 10/2010; 89(2):329-41. · 1.92 Impact Factor
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    ABSTRACT: An experiment was carried out using pigs weighing approximately 30 kg. The animals were fitted with two re-entrant cannulas in duodenum and ileum. During a 5 day period the passage of digesta through duodenum and ileum as well as the excretion by urine and faeces was estimated, taking an aliquot of 5% for N analysis. Transit of digesta amounted to 12.4 ... 13.2. kg/d in the duodenum and 2.7 ... 3.6 kg/d in the ileum. The appertaining N passage rates were 36.8 ... 42.4 resp. 8.7 ... 11.2 g N/d, corresponding to 108 ... 120% and 27 ... 32% of the N intake. The transit rate of duodenal digesta was highest immediately after feeding (1.4 ... 1.5 kg/h), decreased thereafter strongly, reaching a second lower maximum of 0.85 ... 1.0 kg/h 2 ... 3 h after feeding and then going down to 0.3 ... 0.4 kg/h just before the next feeding. The daily mean value was about 500 g/h. Endogenous N content of duodenal digesta varied between 10% after feeding and 50% 6 ... 12 h after feeding, with an average of 18.1%. In contrast the endogenous N content of ileal digesta was relatively constant amounting about 42% during the whole day. These findings correspond with those found by other authors using other rations and other live weights of the pigs. They refer to a clear diurnal rhythm of digesta transit and to the enormous dynamics of absorption and secretion processes in the intestinal tract of pigs during digestion.(ABSTRACT TRUNCATED AT 250 WORDS)
    Archives of Animal Nutrition 09/2009; 40(1-2):17-23. · 0.89 Impact Factor
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    ABSTRACT: In an experiment with 3 pigs (initial live weight 30 kg, each fitted with 2 re-entrant fistulas in duodenum and ileum, one labelled with 15N), the duodenal and ileum digesta was exchanged. The N and 15N contents were estimated in faeces, urine, duodenal and ileum digesta of all experimental animals as well as in special organs and in the contents of different tract sections. The 15N excess (15N') of N compounds secreted into the gut lumen was determined using the 15N' in pancreas, gut mucosa and TCA-soluble blood serum. From measuring the digesta passage through the 3 sections of the digestive tract: 1. mouth ... duodenum, 2. duodenum ... ileum, 3. ileum ... after (Krawielitzki et al., 1989) the absorption and secretion rates of nitrogen were calculated. Secretion into the 1st section amounted to 5.3 g N/d (= 15% of intake) and the absorption to approximately 1% of intake. In the 2nd section the corresponding dates were 8.9 resp. 38.6 g N/d (= 25 resp. 110% of N intake), and in the 3rd one 1.9 resp. 8.4 g N/d (= 5.6 resp. 24% of N intake). Total absorption amounted to 134% of N intake and the over all re-absorption of endogenous N compounds secreted into the gut lumen to about 90%. During the passage the amount of endogenous N (g/d) decreased from 5.3 at the duodenum to 3.8 at the ileum to 1.6 in the faeces, but the relative portion increased (13 resp. 35 resp. 39%). An incorporation into body proteins occurred only from N compounds absorbed in the 1st and in the 2nd section. N (or 15N) absorbed in the large intestine was almost quantitatively excreted by urine. The method of digesta exchange between cannulated labelled and unlabelled pigs seems to be a suitable method to estimate absorption and secretion of exogenous and endogenous N portions in various sections of the digestive tract.
    Archives of Animal Nutrition 09/2009; 40(1-2):25-37. · 0.89 Impact Factor
  • Archives of Animal Nutrition 09/2009; 29(12):771-780. · 0.89 Impact Factor
  • Archives of Animal Nutrition 09/2009; 29(3):151-164. · 0.89 Impact Factor
  • Archives of Animal Nutrition 09/2009; 29(9):541-559. · 0.89 Impact Factor
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    ABSTRACT: The aims of the investigation were to compare calculation methods for ileal apparent digestibility (AD) of amino acids (AA) and to demonstrate the calculation of ileal true digestibility (TD) using the regression approach and additionally, to compare the TD with the standardized digestibility (SD). Eight Goettingen minipigs, average 52 kg initial BW, were fitted with ileo-rectal anastomoses and fed consecutively with assay diets in four experiments according to a Latin rectangle design. To determine AD by using the ‘direct method’, diets contained wheat, lupine, or casein as the sole sources of protein. Furthermore, the ‘difference method’ was used by applying diets with wheat plus casein or wheat plus lupine. To determine AD using the regression (‘Reg2’) method, three graded levels of lupine mixed with wheat were fed. The TD and the basal ileal endogenous losses of AA (ELbAA) were determined using the regression approach (‘Reg1’) by feeding both 5 graded levels of lupine and 5 graded levels of wheat, each added with N-free mixture at 1000 g. In each experiment, one repetition comprised 10 days for adaptation and 4 days for quantitative collection of ileal effluents. Pigs were fed twice a day and the target dietary allowance was 35 g DM kg−0.75 BW d−1 in all experiments. There were no differences in the AD of any AA in lupine or in wheat when those were determined with the direct, difference or Reg2 method. The TD values of the most indispensable AA were higher than the AD (in lupine 8 to 20%-units for lysine and methionine and in wheat 6 to 11%-units for tryptophan and lysine, respectively). These differences reflected the ELbAA derived from the intercept (a) of the Reg1. The ELbAA were higher in lupine than in wheat for arginine, histidine, leucine, methionine, phenylalanine, tryptophan, cysteine, glutamine, and serine (P
    Livestock Science 10/2008; 118(1):61-71. · 1.10 Impact Factor
  • The FASEB Journal 03/2008; 22:869.2.. · 5.48 Impact Factor
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    ABSTRACT: In pigs, the true ileal digestibility (TD), a synonym for standardised ileal digestibility (SID) of crude protein (CP) and amino acids (AA) of lupin and wheat, was determined to characterise their nutritional value as protein feed. Using the regression analysis technique, the basal ileal endogenous losses of AA (EL bAA) induced by feeding lupin and wheat were determined. Furthermore because lupin is used as food, mixtures of both grains and two animal proteins were designed to achieve the AA requirement profile as recommended by (FAO/WHO/UNU, 1985) for preschool-aged children. The TD of CP and AA of lupin and wheat were with few exceptions mostly equal. Lupin induced higher EL b of various AA than wheat. Lupin protein was higher in true digestible Leu, Lys and Thr than wheat but contained less sulfur AA and Trp. A mixture of 17% lupin and 83% wheat resulted in a TD AA pattern close to the recommendation for preschool-aged children (Schaafsma, 2000) except for Lys, Thr, and Trp. A combination of 17% lupin, 75% wheat and 8% milk (dried skim) reduced the discrepancy when compared to the FAO recommendation. Another combination of 17% lupin, 62% wheat and 21% fish protein (dried fishmeal) provided profiles of all indispensable AA including the limited AA Lys, Thr and Trp close to this recommendation.
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    ABSTRACT: We explored whether bifidobacteria and lactobacilli numbers and other selected bacteria in the upper intestine and the caecum of growing pigs were affected by diet and intake of inulin. Starting at two weeks after weaning (28 d) 72 pigs were fed two types of diets (wheat/barley (WB) or maize/gluten (MG)), without or with 3% inulin (WB + I, MG + I) for three and six weeks. Intestinal bacteria were quantified by fluorescence-in-situ-hybridization (n = 8/group). Duration of feeding had no effect on the variables tested, so data for both periods were pooled. Gastric total bacteria amounted to log(10) 7.4/g digesta. Bifidobacteria were detected in stomach and duodenum two weeks after weaning and disappeared thereafter. In jejunum and caecum bifidobacteria were present at a level of log(10) 7.0/g digesta. Inulin did not alter numbers of lactobacilli, bifidobacteria, enterococci, enterobacteria and bacteria of the Clostridium coccoides/Eubacterium rectale-group. Inulin disappearance in stomach plus jejunum was higher with the MG diet (73.7 vs. 60.7%, p = 0.013). Caecal acetate was lower in inulin-supplemented diets (p < 0.05) whereas propionate and butyrate were higher in pigs fed the WB diets (p < 0.05). With the WB diet total caecal short chain fatty acids concentration was higher which resulted in a lower pH value (p < 0.05).
    Archives of animal nutrition 09/2007; 61(4):235-46. · 0.89 Impact Factor
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    ABSTRACT: Introduction There is a great need for better understanding of the intestinal bioavailability of B-vitamins and the factors that influence it. In food products, however, nutrient content does not necessarily imply the proportion of nutrient content actually absorbed. Thus a variety of experimental approaches have been used for determining the intestinal bioavailability of food vitamins. They include measuring changes in tissue vitamin levels, urinary vitamin excretion and growth in response to known intakes of vitamin-containing foods (e.g. Southern and Baker 1981; Gregory and Litherland 1986; Abad and Gregory 1987; Clifford et al. 1990; Swatilo et al. 1990; Yu and Kies 1993; Matte and Girard 1994). Potential limitations of those animal bioassays centre mainly on the role of the intestinal microflora and the extent of enhancement or inhibition of their vitamin synthesis by dietary components. The endogenous vitamin synthesis by the intestinal flora, with possible uptake in the distal part of the small and/or large intestine, is a complicating factor for nearly all B-vitamins. The components of test diets that would stimulate the synthesis of B-vitamins by intestinal microorganisms could therefore cause overestimation of dietary vitamin availability in conventional bioassays. Application of in-vitro assays has also been reported for water-soluble vitamins, but these are not recommended because of the limitations in extrapolation of the results to the situation in vivo (Holler et al. 1975; Seyoum and Selhub 1998). In principle, methods using stable isotopes will give the most reliable information concerning intestinal absorption, but their application is still limited, mainly because stable isotopes are not commercially available and specialized facilities and expertise are required. Ileo-rectal anastomosis has been proposed as an alternative method for calculating the intestinal availability of nutrients (Herrmann et al. 1988; Green and Kiener 1989; Laplace et al. 1989; Hennig et al. 1990; Roth-Maier et al. 1998). The most important advantage of ileo-rectal anastomosis for measuring vitamin digestibility is the prevention of vitamin synthesis by the intestinal microflora and coprophagy, because the digesta can be collected quantitatively via the anus. In this respect two different techniques of ileo-rectal anastomosis have been developed for pigs: the end-to-side (ESV) and end-to-end (EEV) ileo-rectal anastomosis with preserved ileo-caeco-colic valve. Both methods have already been compared for their use as digestibility assays for the vitamins including thiamin, riboflavin and vitamin B6 (Roth-Maier et al. 1998). The objective of the present study was to compare both the ESV and EEV techniques with regard to the digestibility values of folate, niacin and pantothenic acid, which has not been tested hitherto. In addition, in order to examine age- or time-related effects on vitamin digestibility two different experimental periods after surgery were chosen for measurement.
    J Anim Physiol a Anim Nutr 08/2007; 82(2‐3):80 - 87. · 1.25 Impact Factor
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    ABSTRACT: Juvenile growing pigs were studied to explore whether a soy-based diet can induce persistent physiological alterations, especially in protein and energy metabolism, nutrient oxidation and redox homeostasis. In former studies we have shown that in juvenile pigs chronically fed protein diets based on either casein (CAS) or soy protein isolate (SPI), the SPI diet significantly decreases growth rate and increases oxidative stress responsiveness as compared to CAS. In addition, here we show that chronic feeding of SPI vs. CAS diet decreases whole body protein synthesis (WBPS) (p = 0.007) and hepatic gene expression associated with protein synthesis. To study persistent SPI effects, a three-period feeding experiment was designed: In the test group 18 pigs received the CAS diet for 24 days (period 1), followed by 31 days on the SPI diet (period 2) and further 31 days on the CAS diet (period 3). In the control group 18 pigs were fed the CAS diet throughout the three periods (86 days). Temporary consumption of SPI diet results in persistent changes of protein metabolism and oxidative stress responsiveness. After switching back from SPI to CAS diet the decrease of WBPS of the test group vs. control group was of borderline significance (p = 0.061), transcript levels of hepatic gene expressions of leucine aminopeptidase, endopeptidase 24.16, glutathione-S-transferase and peptide methionine sulfoxide reductase were increased. In liver tissue, total glutathione was increased and thiobarbituric acid reactive substances were decreased in the test vs. control group. In conclusion, results suggest that SPI-induced changes in protein and amino acid metabolism as well as in redox homeostasis and antioxidative potential in growing pigs persist 4 weeks after the cessation of SPI feeding.
    Archives of animal nutrition 05/2007; 61(2):75-89. · 0.89 Impact Factor
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    ABSTRACT: Five barrows (58 kg initial BW, 80 kg final BW) fitted with an ileo-rectal anastomosis were used to determine the effect of partial dehulling of two- and six-row barley varieties on the concentrations of ileal digestible amino acids (AA). The following diets were provided according to a standardized diet formulation and tested in five consecutive periods (repeated group-period design): two-row barley (TRB)+casein (C), dehulled TRB (TRB-H)+C, six-row barley (SRB)+C, dehulled SRB (SRB-H)+C, and wheat starch+C. Daily rates of approximately 80 g DM×kg BW−0.75 in barley diets and 49 g DM×kg BW−0.75 in the casein diet were supplied. The digestibility of AA in barley was determined by the difference method (casein as basal diet) using quantitative ileal effluent collection.In TRB and SRB the ID of CP and AA did not differ. As demonstrated on selected key AA there were increases of both concentrations of gross AA and of ileal AA digestibility duo to dehulling. Consequently, the contents of ileal digestible AA were raised by up to 39% for lysine and 38% for methionine in TRB-H and SRB-H, respectively.
    Livestock Science 05/2007; 109(1):129-131. · 1.10 Impact Factor
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    ABSTRACT: Our results in a previous study indicated that the portal absorption of intragastrically fed α-ketoglutarate (AKG) was limited in young pigs. Our aim was to quantify the net portal absorption, first-pass metabolism, and whole-body flux of enterally infused AKG. In study 1, we quantified the net portal nutrient absorption in young pigs (n = 9) given an intraduodenal infusion of milk replacer [10 mL/(kg · h)] and either saline (control) or 930 μmol/(kg · h) AKG for 4 h. In study 2, we quantified the luminal disappearance of a duodenal AKG bolus in young pigs (n = 7). In study 3, we quantified the whole-body kinetics of ¹³C-AKG metabolism when infused either enterally (n = 9) or intravenously (n = 9) in young pigs. In study 1, when compared with the control group, enteral AKG infusion increased (P < 0.01) the arterial (13.8 ± 1.7 vs. 27.4 ± 3.6 μmol/L) and portal (22.0 ± 1.4 vs. 64.6 ± 5.9 μmol/L) AKG concentrations and the net portal absorption of AKG [19.7 ± 2.8 vs. 95.2 ± 12.0 μmol/(kg · h)]. The mean fractional portal appearance of enterally infused AKG was 10.23 ± 1.3%. In study 2, the luminal disappearance of AKG was 663 μmol/(kg · h), representing 63% of the intraduodenal dose. In study 3, the whole-body ¹³C-AKG flux [4685 ± 666 vs. 801 ± 67 μmol/(kg · h)] was higher (P < 0.05) when given enterally than intravenously, but ¹³CO₂ recovery was not different (37.3 ± 1.0 vs. 36.2 ± 0.7%dose). The first-pass splanchnic ¹³C-AKG utilization was ~80%, of which 30% was oxidized to ¹³CO₂. We conclude that the intestinal absorption of AKG is limited in young pigs largely due to substantial first-pass gastrointestinal metabolism.
    Journal of Nutrition 11/2006; 136(11):2779-2784. · 4.23 Impact Factor
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    ABSTRACT: Our results in a previous study indicated that the portal absorption of intragastrically fed alpha-ketoglutarate (AKG) was limited in young pigs. Our aim was to quantify the net portal absorption, first-pass metabolism, and whole-body flux of enterally infused AKG. In study 1, we quantified the net portal nutrient absorption in young pigs (n = 9) given an intraduodenal infusion of milk replacer [10 mL/(kg . h)] and either saline (control) or 930 micromol/(kg . h) AKG for 4 h. In study 2, we quantified the luminal disappearance of a duodenal AKG bolus in young pigs (n = 7). In study 3, we quantified the whole-body kinetics of (13)C-AKG metabolism when infused either enterally (n = 9) or intravenously (n = 9) in young pigs. In study 1, when compared with the control group, enteral AKG infusion increased (P < 0.01) the arterial (13.8 +/- 1.7 vs. 27.4 +/- 3.6 micromol/L) and portal (22.0 +/- 1.4 vs. 64.6 +/- 5.9 micromol/L) AKG concentrations and the net portal absorption of AKG [19.7 +/- 2.8 vs. 95.2 +/- 12.0 micromol/(kg . h)]. The mean fractional portal appearance of enterally infused AKG was 10.23 +/- 1.3%. In study 2, the luminal disappearance of AKG was 663 micromol/(kg . h), representing 63% of the intraduodenal dose. In study 3, the whole-body (13)C-AKG flux [4685 +/- 666 vs. 801 +/- 67 micromol/(kg . h)] was higher (P < 0.05) when given enterally than intravenously, but (13)CO(2) recovery was not different (37.3 +/- 1.0 vs. 36.2 +/- 0.7%dose). The first-pass splanchnic (13)C-AKG utilization was approximately 80%, of which 30% was oxidized to (13)CO(2). We conclude that the intestinal absorption of AKG is limited in young pigs largely due to substantial first-pass gastrointestinal metabolism.
    Journal of Nutrition 11/2006; 136(11):2779-84. · 4.23 Impact Factor
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    ABSTRACT: Five barrows (German Landrace; initial BW 58 kg, final BW 80 kg) fitted with an ileo-rectal anastomosis were used to determine the effect of partial dehulling and addition of barley hulls of two- and six-row barley varieties on the precaecal digestibility (pD) of CP and amino acids. The following diets were provided according to a standardized diet formulation and tested in seven consecutive periods (repeated group-period design): two-row barley (TRB) + casein (C), dehulled TRB + C, TRB + C + 10% hulls, six-row barley (SRB) + C, dehulled SRB + C, SRB + C + 1% hulls, and wheat starch + C. The diets were supplied at daily rates of 79-86 g DMI x kg BW(-0.75) in barley containing diets and at 49 g DMI x kg BW(-0.75) in the casein diet. The digestibility of amino acids in barley varieties was determined by the difference method (casein as basal diet) using quantitative digesta collection. In both varieties of barley the pD of CP and amino acids did not differ. The pD of CP was unchanged in regard to the treatments in both barley varieties. Due to dehulling in TRB the pD was improved significantly for most indispensable amino acids and in SRB for Met and Cys. Addition of 10% hulls to TRB led to equivalent pD of Arg, His, Leu, Tyr, and Trp compared to TRB, but the pD of Lys, Phe, Thr and Val was significantly decreased below the levels of TRB. Addition of even 1% hulls to SRB impaired the pD of Lys below the level in SRB. In conclusion, addition of barley hulls to pig diets impairs amino acids absorption in the small intestine. The pD values, measured under standardized experimental conditions (without a correction using basal endogenous amino acids), are similar to the values of true digestibility published by NRC (1998).
    Archives of animal nutrition 07/2006; 60(3):205-17. · 0.89 Impact Factor
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    ABSTRACT: alpha-Ketoglutarate (AKG) has been suggested to play a particular role as an oxidative fuel for the gut, and thus may have a sparing function for fuels such as glutamate and aspartate. Using the pig model we aimed to quantify how the route of administration (intravenous, i.v.; intragastric, i.g.; intraduodenal, i.d.) affects AKG utilization, whole body energy expenditure (EE) and nutrient oxidation. Pigs (15 kg) were supplied with a complete nutrient solution (NS) via catheters. To explore the metabolic effects of AKG, 1.0 g AKG kgBW(-1)d(-1) was infused simultaneously with the NS using either the i.d., i.v. or i.g. route. [1-(13)C]AKG (15 mg kgBW(-1)) was infused i.d., i.v. or i.g., respectively, for 3h. AKG utilization (AKG UTIL) was estimated as AKG UTIL=100-(13)C recovery (% of (13)C dose). (13)C recovery was calculated from the (13)C enrichment in breath CO(2) and the whole-body CO(2) production. AKG infusion and NS via the i.d. route resulted in a reduced AKG UTIL (40.1+/-6.7) as compared to the i.v. route (62.9+/-2.4, P<0.001) and i.g. route (62.3+/-1.6, P<0.001). The total EE was lower with the i.d. route of AKG and NS (745+/-68 kJkgBW(-0.62)d(-1)) as compared to the i.v. route (965+/-54 kJkgBW(-0.62)d(-1), P<0.005) and i.g. route (918+/-43 kJkgBW(-0.62)d(-1), P<0.005). Carbohydrate oxidation was increased with the i.d. route (38.2g+/-3.4 kgBW(-0.62)d(-1)) as compared to the i.v. route (27.8+/-2.9 gkgBW(-0.62)d(-1), P<0.08) and i.g. route (23.9+/-8.5 gkgBW(-0.62)d(-1), P<0.05). Fat oxidation was decreased (2.1+/-1.9 gkgBW(-0.62)d(-1); P<0.001) with the i.d. route as compared to the i.v. route (11.5+/-1.4 gkgBW(-0.62)d(-1), P<0.001) and i.g. route (11.9+/-3.1 gkgBW(-0.62)d(-1), P<0.001). The i.d. infusion of AKG in combination with the NS affected the whole body EE and nutrient oxidation, in comparison to that obtained with the i.v. and i.g. routes. It was concluded that the i.d. administration of AKG markedly controlled the nutrient partitioning in the oxidation processes. Finally, in contrary to the observations with glutamine or glutamate, a considerable percentage of the AKG infusion was retained in the body irrespective of the route of administration.
    Clinical Nutrition 07/2006; 25(3):489-96. · 3.94 Impact Factor