N.P. Kjos
Norwegian University of Life Sciences
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Featured researches published by N.P. Kjos.
Animal | 2012
S. G. Vhile; N.P. Kjos; H. Sørum; Margareth Øverland
Different levels of dried Jerusalem artichoke were fed to entire male pigs 1 week before slaughter. The objective was to investigate the effect on skatole level in the hindgut and in adipose tissue, as well as the effect on microflora and short-chain fatty acids (SCFA) in the hindgut. Five experimental groups (n = 11) were given different dietary treatments 7 days before slaughtering: negative control (basal diet), positive control (basal diet + 9% chicory-inulin), basal diet + 4.1% Jerusalem artichoke, basal diet + 8.1% Jerusalem artichoke and basal diet + 12.2% Jerusalem artichoke. Samples from colon, rectum, faeces and adipose tissue were collected. Effect of dietary treatment on skatole, indole and androstenone levels in adipose tissue and on skatole, indole, pH, dry matter (DM), microbiota and SCFA in the hindgut was evaluated. Feeding increasing levels of Jerusalem artichoke to entire male pigs reduced skatole in digesta from colon and in faeces (linear, P < 0.01). There was also a tendency towards a decreased level of skatole in adipose tissue (linear, P = 0.06). Feeding Jerusalem artichoke decreased DM content in colon and faeces and pH in colon (linear, P < 0.01). Increasing levels of Jerusalem artichoke resulted in a reduced level of Clostridium perfringens in both colon and rectum (linear, P < 0.05) and a tendency towards decreased levels of enterobacteria in colon (linear, P = 0.05). Further, there was an increase in total amount of SCFA (linear, P < 0.05), acetic acid (linear, P < 0.05) and valerianic acid (linear, P < 0.01) in faeces. In conclusion, adding dried Jerusalem artichoke to diets for entire male pigs 1 week before slaughter resulted in a dose-dependent decrease in skatole levels in the hindgut and adipose tissue. The reduced skatole levels might be related to the decrease in C. perfringens and the increase in SCFA with subsequent reduction in pH.
Italian Journal of Animal Science | 2004
Margareth Øverland; N.P. Kjos; Anders Skrede
Abstract Bacterial protein meal (BPM), a new protein feedstuff produced by bacteria (Methylococcus capsulatus, Alcaligenes acidovorans, Bacillus brevis and Bacillus firmus) grown on natural gas, was evaluated as a protein source for pigs. Two growth trials were conducted, one with growing-finishing pigs and one with pigs from weaning until slaughter. In Exp. 1, 18 pigs fed restrictively (26.0 and 109.4 kg initial and final weight) were used to determine the effect of dietary inclusion of BPM (0, 60, or 120 g kg-1), replacing protein from soybean meal on growth performance and carcass traits. Adding 60 and 120 g kg-1 BPM to diets reduced (P < 0.01) ADG and feed efficiency during the growing period, but had no effect on growth performance during the finishing or overall periods. Both levels of BPM improved amino acid and lysine utilization (P < 0.01) compared with the control. Fat firmness tended to increase with inclusion of BPM. When using orthogonal contrast, both levels of BPM tended to increase carcass meatiness. In Exp. 2, 48 pigs (11.4 and 107.2 kg initial and final weight) were used to evaluate increasing levels of BPM (0, 50, 100, or 150 g kg –1) on growth performance and carcass traits from weaning at 34.5 days of age until slaughter. Bacterial protein meal reduced ADG (linear P < 0.03) during the period from weaning until five weeks post weaning and during the period from weaning until slaughter. Increasing levels of BPM tended to increase overall feed/gain. Also, BPM increased backfat firmness (linear P < 0.01), but reduced percent carcass lean (linear P < 0.05) and carcass meatiness (linear P < 0.01), and increased P2 backfat thickness and fat area in cutlet (linear P < 0.05). All levels of BPM improved amino acid and lysine utilization (linear P < 0.05) compared with the control. In conclusion, up to 120 g kg –1 BPM in diets for pigs from 26 kg live weight until slaughter had no adverse effect on overall growth performance or carcass lean or fat content. Up to 150 g kg –1 BPM to diets for pigs from weaning until slaughter reduced growth rates during the piglet period and increased carcass fat content due to marginal dietary lysine levels. Bacterial protein meal gave a dose dependent improvement in the utilization of total amino acids and lysine and the quality of back fat determined as fat firmness and fat color.
Meat Science | 2010
E. Hallenstvedt; N.P. Kjos; A.C. Rehnberg; M. Øverland; M. Thomassen
A total of 72 crossbred [(Norwegian Landrace x Yorkshire) x Duroc] male and female growing-finishing pigs were restrictedly fed diets containing fish oil to study the fatty acid composition of Musculus longissimusdorsi and sensory quality of belly and neck. Six diets were used: two low-fat diets with or without 0.5% fish oil added, and four medium-fat diets with palm kernel oil to fish oil in ratios given as % inclusion: 4.1:0.0, 3.9:0.3, 3.6:0.5 and 3.4:0.7. Feeding fish oil gave a dose-dependent response between fatty acids in the diets and in the M.longissimusdorsi and increased the level of very long chain n-3 fatty acids, especially the C22:5n-3 (DPA). A more efficient n-3 fatty acids deposition was obtained when given as a medium-fat diet rather than the low-fat diet. Female pigs had a significant higher percentage of monounsaturated fatty acids and C18:1 than males suggesting a gender related difference in the delta-9-desaturase activity. No significant differences were found in sensory attributes for short-term stored neck and belly. For pigs fed the highest level of fish oil (0.7%) long-term stored (12 months at -80 degrees C, 6 months at -20 degrees C) belly showed a slight increase in fish oil flavour. After warmed-over treatment, fish oil odour and flavour as well as rancid flavour were increased in this group. The results suggest levels of dietary fish oil up to 0.5% produce a healthier meat fatty acid composition, without negative effects on sensory attributes, even in long-termed stored belly.
Meat Science | 2005
M. Øverland; N.P. Kjos; E. Olsen; Anders Skrede
A total of 48 pigs (11.4 and 107.2 kg initial and final weight) were used to evaluate increasing dietary levels of bacterial protein meal (BPM) produced on natural gas (0, 50, 100, or 150 g kg(-1)) on fatty acid composition, sensory properties, and susceptibility of pork to lipid oxidation. Increasing levels of BPM to diets increased the content of C16:1 fatty acids in backfat and muscle and total monounsaturated fatty acids in muscle, but decreased the content of polyunsaturated fatty acids and iodine value in backfat and muscle. Pigs fed diets containing BPM had reduced thiobarbituric acid reactive substances (TBARS) value in backfat and muscle, reduced intensity of odor and rancid odor and taste in pork after short-time storage, and reduced off-odor and off-taste after intermediate-time storage. To conclude, adding BPM to diets for pigs changed the fatty acid profile, improved the oxidative stability, and sensory quality of pork.
Meat Science | 2012
E. Hallenstvedt; N.P. Kjos; M. Øverland; M. Thomassen
Two experiments with 72 slaughter pigs in each were conducted. Entire males and females were individually fed restricted. Palm kernel-, soybean- and fish-oil were used in varying combinations, giving different dietary fat levels (29-80g/kg) and iodine values ranging from 50 to 131. Shoulder fat was analysed for fatty acid composition (inner and outer layer), firmness and colour. A clear dose-response relationship was seen between fatty acids in diets and in shoulder fat. Interestingly, the very long chain n-3 fatty acids seemed to be deposited more efficiently when additional fat was included in the diet. Both high and low dietary iodine values changed towards less extreme iodine values in fat. Low-fat diets enhanced de novo synthesis of fatty acids. Males revealed a higher percentage of PUFA and a lower percentage of C18:1 and MUFA. Fat firmness, but not colour, was influenced by sex and dietary fat source.
Meat Science | 2010
H. Sterten; Niels Oksbjerg; T. Frøystein; A.S. Ekker; N.P. Kjos
The aim of this study was to investigate the effect of pre-slaughter fasting time, sex and feeding regime on the development of energy metabolism and pH in M. longissimusdorsi (LD) post-mortem in pigs. Two hundred and seventy pigs of the commercial Norwegian crossbreed Noroc (LYLD) were used involving two sexes (gilts and castrates), two feeding regimes (restricted and ad libitum) and four different fasting treatments: (F4) 4h fasting, (F175) 17.5h fasting on the farm, (FO175) 17.5h fasting overnight at the abattoir, and (FO265) 26.5h fasting overnight at the abattoir. Additionally the pigs experienced two different abattoir lairage times as fasting treatment F4 and F175 had a lairage time of 1.5h, while fasting treatment FO175 and FO265 had a lairage time of 23.0 h. A short fasting time of 4 h led to a delayed degradation of glycogen, slow decline in pH and a lower ultimate pH(45 h) post-mortem (pHu) in the LD compared with a fasting time of 26.5 h which resulted in a rapid breakdown of glycogen and pH decline early post-mortem and a high pHu. Proglycogen was degraded in favour of macroglycogen under anaerobic conditions post-mortem. Feeding the animals in the morning before delivery if slaughtered the same day, results in low pH reduction rate and a low pHu compared with pigs fasted overnight either on farm or at the abattoir. Aiming a higher pHu in LD it should be recommended not to feed the pigs in the morning at the day of slaughter.
Meat Science | 2009
H. Sterten; T. Frøystein; Niels Oksbjerg; A.C. Rehnberg; A.S. Ekker; N.P. Kjos
The aim of this study was to investigate the effect of pre-slaughter fasting time, sex and feeding regime on water-holding capacity (WHC), colour and sensory properties and their relationship with pH in M. longissimusdorsi (LD) in pigs. 270 pigs of the commercial Norwegian crossbreed Noroc (Norwegian Landrace×Yorkshire sow and Norwegian Landrace×Duroc boar) were used involving two sexes (gilts and castrates), two feeding regimes (restricted and ad libitum) and four fasting treatments: (F4) 4h fasting (control), (F175) 17.5h fasting on the farm, (FO175) 17.5h fasting overnight at the abattoir, and (FO265) 26.5h fasting overnight at the abattoir. Additionally, the pigs experienced two abattoir lairage times as fasting treatments F4 and F175had a lairage time of 1.5 h, while fasting treatments FO175 and FO265 had a lairage time of 23.0h. A short fasting time of 4h led to a delayed decline in pH post-mortem and a lower ultimate pH (pHu) in the LD compared with a fasting time of 26.5h which resulted in a rapid pH decline early post-mortem and a high pHu. Prolonged fasting reduced drip loss, resulted in a darker colour and tended to improve tenderness of the LD. Castrates showed lower drip loss, higher lightness and improved tenderness and juiciness compared with gilts, while ad libitum feeding improved tenderness compared to restricted feeding. There are obvious negative relationships between pHu and drip loss, lightness and tenderness of LD.
Lipids in Health and Disease | 2008
Anna Haug; Per Sjögren; Hanne Müller; N.P. Kjos; O. Taugbøl; Nina Fjerdingby; Anne S. Biong; Eirik Selmer-Olsen; Odd Magne Harstad
BackgroundCow milk is a natural source of the cis 9, trans 11 isomer of conjugated linoleic acid (c9,t11-CLA) and trans vaccenic acid (VA). These fatty acids may be considered as functional foods, and the concentration in milk can be increased by e.g. sunflower oil supplementation to the dairy cow feed.The objective of this study was to compare the effects of regular butter with a special butter naturally enriched in c9,t11-CLA and VA on plasma lipids in female growing pigs. The experimental period lasted for three weeks and the two diets provided daily either 5.0 g c9,t11-CLA plus 15.1 g VA or 1.3 g c9,t11-CLA plus 3.6 g VA.ResultsThe serum concentrations of c9,t11-CLA, VA and alpha-linolenic acid were increased and myristic (14:0) and palmitic acid (16:0) were reduced in the pigs fed the CLA+VA-rich butter-diet compared to regular butter, but no differences in plasma concentrations of triacylglycerol, cholesterol, HDL-cholesterol, LDL-cholesterol, LDL particle size distribution or total cholesterol/HDL cholesterol were observed among the two dietary treatment groups.ConclusionGrowing pigs fed diets containing butter naturally enriched in about 20 g c9,t11-CLA plus VA daily for three weeks, had increased serum concentrations of alpha-linolenic acid and decreased myristic and palmitic acid compared to pigs fed regular butter, implying a potential benefit of the CLA+VA butter on serum fatty acid composition. Butter enriched in CLA+VA does not appear to have significant effect on the plasma lipoprotein profile in pigs.
Journal of Agricultural and Food Chemistry | 2013
Anastasia S. Hole; N.P. Kjos; Stine Grimmer; Achim Kohler; Per Lea; Bård Rasmussen; Lene R. Lima; Judith Narvhus; Stefan Sahlstrøm
To evaluate the bioaccessibility of phenolic acids in extruded and nonextruded cereal grains, an in vivo experiment was carried out using growing pigs as a model system. Four diets were prepared containing either whole grain barley (BU), dehulled oat (OU), or their respective extruded samples (BE, OE) according to the requirements for crude protein, mineral, and vitamin contents in pig diets. The total contents of free phenolic acids in the OE and BE diets were 22 and 10%, respectively, higher compared with the OU and BU diets, whereas the level of bound phenolic acids was 9% higher in OE than in OU and 11% lower in BE compared with BU. The total tract bioaccessibilities of bound phenolic acids were 29 and 14% higher for the extruded BE and OE diets, respectively, compared with the nonextruded diets. The results of this study indicate an improved bioaccessibility of phenolic acids in extruded cereal grains.
Archives of Animal Nutrition | 2007
Anne Louise Frydendahl Hellwing; Anne-Helene Tauson; Anders Skrede; N.P. Kjos; Øystein Ahlstrøm
Abstract The effect of increasing the dietary content of bacterial protein meal (BPM) on protein turnover rate, and on nucleic acid and creatinine metabolism in growing minks and pigs was investigated in two experiments. In each experiment, 16 animals were allocated to four experimental diets. The diets containing no BPM served as controls, i.e. for minks diet M1, for pigs P1; the experimental diets contained increasing levels of BPM to replace fish meal (minks) or soybean meal (pigs), so that up to 17% (P2), 20% (M2), 35% (P3), 40% (M3), 52% (P4), and 60% (M4) of digestible N was BPM derived. Protein turnover rate was measured by means of the end-product method using [15N]glycine as tracer and urinary nitrogen as end-product. In minks, protein flux, synthesis, and breakdown increased significantly with increasing dietary BPM. In pigs, diet had no observed effect on protein turnover rate. The intake of nucleic acid nitrogen (NAN) increased from 0.15 g/kg W0.75 on M1 to 0.26 g/kg W0.75 on M3 and M4 in the mink experiment, and from 0.08 g/kg W0.75 on P1 to 0.33 g/kg W0.75 on P4 in the pig experiment. Increased NAN intake led, in both experiments, to increased allantoin excretion. Analysis of species effects showed that minks excreted 1.72 mmol/kg W0.75 of allantoin, significantly more than the 0.95 mmol/kg W0.75 excreted by pigs. In minks, approximately 96% of the excreted purine base derivatives consisted of allantoin, whereas in pigs approximately 93% did. Thus, increasing the dietary content of BPM increased protein turnover rate in minks but not in pigs, and allantoin excretion increased with increasing dietary BPM although it seemed that mink decomposed purine bases to their end-product more completely than pigs did. Collectively these data show that BPM is a suitable protein source for pigs and mink, and recorded differences between species were to a large extent due to differences in protein retention capacity and muscle mass.