Biomedical subjects

J Zentek

Publications and source records attributed to J Zentek.

At least 19 recordsLinked to original sources

PubMed2007

Dietary inulin affects the morphology but not the sodium-dependent glucose and glutamine transport in the jejunum of broilers.

Inulin, a prebiotic, is a fermentable oligosaccharide that may affect the intestinal mucosal architecture and the electrophysiological parameters. The effects of a diet with added inulin were tested on the jejunal morphology and electrogenic transport of Glc and Gln from the jejunal mucosa in broilers. Short-circuit current and transmucosal tissue resistance of jejunal flaps were measured in Ussing chambers. The feeding experiment was carried out in broilers (n = 40) using 1% inulin with an application period of 5 wk. The inulin-containing diet resulted in longer jejunal villi (P < 0.05) and deeper crypts (P < 0.01) than in control birds without affecting villus:crypt depth. Basal short-circuit current value remained unaffected by dietary treatment. Inulin supplementation did not modify the electrogenic transport of Glc and Gln in the jejunal mucosa. The basal value of transmucosal tissue resistance was significantly lower (P < 0.001) in the inulin-fed group compared with the control group. In conclusion, inulin supplementation affected the jejunal mucosal architecture but did not modify the electrogenic transport of Glc and amino acid under present experimental condition.

Animal Feed↗

PubMed2007

In vitro effects of deoxynivalenol on small intestinal D-glucose uptake and absorption of deoxynivalenol across the isolated jejunal epithelium of laying hens.

Deoxynivalenol (DON) is a common mycotoxin contaminant in feedstuffs. It has been shown to cause diverse toxic effects in animals. The aim of the present study was to evaluate the effects of DON on the glucose transport capacity in chickens' jejunum and to investigate the permeation of DON itself by the Ussing chamber technique. Glucose uptake into chicken jejunal epithelia was measured after the addition of 200 mumol/L of (14)C-labeled glucose to the mucosal solution. Glucose uptake under control condition was 3.28 +/- 0.53 nmol/cm(2) x min. The contribution of sodium glucose-linked transporter 1 (SGLT-1) to total glucose uptake was estimated by inhibiting SGLT-1 with phlorizin (100 micromol/L). In the presence of phlorizin, glucose uptake was reduced (P < 0.05) to 1.21 +/- 0.19 nmol/cm(2) x min. Deoxynivalenol decreased (P < 0.05) the glucose uptake in the absence of phlorizin to 1.81 +/- 0.24 nmol/cm(2) x min but had no additional effect on the glucose uptake in the presence of phlorizin (0.97 +/- 0.17 nmol/cm(2) x min). Mucosal-to-serosal permeation of DON was proportional to the initial DON concentration over a concentration range from 1 to 10 mug/mL on the mucosal side. Apparent permeability at 10 microg/mL of DON measured 60 to 90 min after DON application was 1.7 x 10(-05) cm/s. It can be concluded that DON (10 mg/L) decreases glucose uptake almost as efficiently as phlorizin. The similarity between the effects of phlorizin and DON on glucose uptake evidences their common ability to inhibit Na(+)-D-glucose cotransport. In addition to local effects, DON can be absorbed from the jejunum. A predominant part of DON passes across the chicken intestinal epithelium by passive diffusion, which is likely on the paracellular pathway. The results imply that the exposure to DON-contaminated feeds may negatively affect animal health and performance by local (i.e., inhibition of intestinal SGLT-1) and systemic effects.

Absorption↗

PubMed2007

Blood vitamin concentrations in privately owned dogs fed non-standardized commercial diets and after intake of diets with specified vitamin concentrations.

The objective was to investigate in a survey study the blood vitamin concentrations in healthy dogs fed non-specified commercial complete diets and in an intervention study to determine the effects of defined dietary vitamin intakes on blood vitamin levels and hair and skin condition. Sixty-four privately owned dogs, aged from 1 to 8 years, without history of skin or coat problems were included. All animals were fed commercial complete diets with uncertain vitamin concentrations before enrolment. The animals were assigned, according to weight and gender, to four groups with graded vitamin intakes. The blood vitamin levels and skin and coat quality of the dogs were investigated at days 0 and day 122. Coat and hair condition was not influenced by the experimental diets. The retinol concentrations were reduced at the end of the experiment compared with the baseline levels, retinyl esters were not influenced. 25-Hydroxycholecalciferol decreased in all groups, alpha-tocopherol was constant or tended to decrease. Ascorbic acid, thiamine pyrophosphate and riboflavin concentrations were not affected by treatment, flavin adenine dinucleotide and pyridoxal-5'-phosphate were partially reduced on day 122. Cobalamin, pantothenate and biotin concentrations increased with higher dietary intakes, folate levels in tendency. In conclusion, this study gives a survey of blood vitamin concentrations in healthy dogs and provides a data base for the evaluation of the vitamin status in health and disease.

Animal Feed↗

PubMed2006

Determination of zearalenone and its metabolites in urine, plasma and faeces of horses by HPLC-APCI-MS.

The paper describes a method for the sensitive and selective determination of zearalenone and its metabolites in urine, plasma and faeces of horses by high performance liquid chromatography and atmospheric pressure chemical ionisation (APCI) mass spectrometry (MS). While only one step sample clean-up by an immunoaffinity column (IAC) was sufficient for plasma samples, urine and faeces samples had to be prepared by a combination of a solid-phase extraction (SPE) and an immunoaffinity column. The method allows the simultaneous determination of zearalenone and all of its metabolites; alpha-zearalenol, beta-zearalenol, alpha-zearalanol, beta-zearalanol and zearalanone. Dideuterated zearalanone was used as internal standard for quantification and the study of the matrix effect. Recovery rates between 56 and slightly above 100% were achieved in urine samples, and more than 80% in plasma and faeces samples. The limits of detection ranged from 0.1-0.5 microg/l or microg/kg, the limits of quantification from 0.5-1.0 microg/l or microg/kg. The practical use of the method is demonstrated by the analysis of spiked and naturally contaminated urine, plasma and faeces of horses.

Analytic Sample Preparation Methods↗

PubMed2006

Transient erythropoietic protoporphyria associated with chronic hepatitis and cirrhosis in a cohort of German shepherd dogs.

Over the course of one year, slight jaundice and ascites suggestive of chronic liver disease occurred in 17 German shepherd dogs from one breeding colony. Blood analyses, performed twice with a six-month interval, revealed elevated serum activities of liver enzymes in 13 dogs. In addition, four young adult German shepherd dogs that showed severe ascites, slight jaundice and increased serum liver enzyme activities were referred for further evaluation. Because of their poor prognosis these four dogs were euthanased. There were no signs of photosensitivity. Postmortem examinations revealed macronodular darkened livers, which were characterised histopathologically by cirrhosis associated with aggregates of brown pigments showing a striking orange birefringence in polarised light. Ultrastructurally, the crystalline pigments were typical of protoporphyrins. High-performance liquid chromatographic analysis of liver samples revealed very high levels of protoporphyrins (mean 9550 nmol/g wet liver, reference value 0.41 nmol/g wet liver) and low activities of ferrochelatase (mean 0.274 mmol/mg protein/hour, reference value 0.684 nmol/mg protein/hour). Twenty-six months after the onset of the hepatopathies, the clinical condition of the 13 surviving dogs had improved and their serum liver enzyme activities were normal. The clinical histories and pedigree analyses were not in concordance with an inherited form of protoporphyria. There was no known history of exposure to toxic substances or drugs. The findings are in accordance with a transient erythropoietic protoporphyria associated with hepatic complications, presumably caused by exposure to a porphyrinogenic, ferrochelatase-inhibitory substance of unknown origin.

Animals↗

PubMed2006

Effect of addition of a probiotic microorganism to broiler diets contaminated with deoxynivalenol on performance and histological alterations of intestinal villi of broiler chickens.

An experiment was conducted to study the effects of deoxynivalenol (DON) on the performance of broilers, organ weights, and intestinal histology and to evaluate the efficacy of a probiotic feed additive (PB, Eubacterium sp.) with the ability to deepoxidize DON. Two hundred seventy-seven 1-d-old broiler chicks were randomly assigned to 1 of the 3 dietary treatments for 6 wk. The dietary treatments were 1) control; 2) artificially contaminated diets with 10 mg of DON/kg of diet; 3) DON-contaminated diets plus probiotic feed additive (DON-PB). The BW and the efficiency of feed utilization were not adversely affected (P > 0.05) by the inclusion of DON in the diets. A slight improvement in feed intake and BW gain over the course of the experiment was observed in broilers fed DON-PB with no change in feed efficiency. The absolute or relative organ weights were not altered (P > 0.05) in broilers fed the diet containing DON compared with controls and the DON-PB group. The absolute liver weights were numerically increased (P < 0.1) for broilers receiving the diet containing DON-PB. There were no significant differences in the absolute and relative weights of the gizzard, duodenum, pancreas, heart, and spleen. However, the absolute and relative weights of the jejunum and cecum were increased for DON-PB-fed broilers compared with the controls and DON group. No pathological lesions were found in the gut of birds fed DON-contaminated diets during the feeding trial, but mild intestinal changes were observed. The DON altered small intestinal morphology, especially in the duodenum and jejunum, where villi were shorter and thinner (P < 0.05). The addition of the eubacteria to the DON-contaminated feed of the broilers effectively alleviated the histological alterations caused by DON and led to comparable villus length as in the control group. In conclusion, diets with DON contamination below levels that induce a negative impact on health and performance could affect small intestinal morphology in broilers. The histological alterations caused by DON were reduced by supplementing the DON-containing diets with PB. This indicates that in case of DON contamination of feedstuffs, the addition of PB would be a proper way to counteract the possible effects caused by this mycotoxin.

Animals↗

PubMed2006

Clostridium perfringens alpha toxin affects electrophysiological properties of isolated jejunal mucosa of laying hens.

Bacteria that colonize the intestinal tract can invade epithelial cells or produce toxins that cause diarrhoeal diseases. Proliferation of Clostridium perfringens and production of alpha-toxin, a phospholipase C, is the major factor for necrotic enteritis in poultry. However, little is known about the functional importance of luminal alpha-toxin during intestinal infection. The purpose of this study was to investigate the effects of purified alpha toxin of Clostridium perfringens on the electrophysiology of the laying hen's stripped jejunum in Ussing chambers. The effects were investigated in Experiment 1 after toxin addition to the mucosal and serosal side of the tissue, and a second experiment was performed to study the effect of the toxin on sodium-dependent glucose transport. Mucosal exposure of jejunal tissue sheets to 100 units of alpha toxin/L did not elicit electrophysiologic changes. The addition of purified alpha toxin to the serosal side induced a biphasic increase in short-circuit current (ISC) after 15 and 100 min. The magnitude of the increase of ISC of both peaks was similar, but the second phase response lasted longer. The tissue conductivity tended (P = 0.07) to be lower after 2 h of toxin addition compared with basal value when no toxin was added. In the second experiment, adding D-glucose on the mucosal side of the jejunum increased (P < 0.05) the ISC from a baseline value of 42 +/- 28 microA/cm2 to a maximal value of 103 +/- 27 microA/cm2. Preincubation with alpha-toxin almost fully inhibited this stimulation of ISC by D-glucose. The conductance of the tissues was not affected by the toxin addition. These findings indicate that alpha toxin not only causes electrogenic secretion of anions, probably due to the stimulation of chloride secretion, but also diminishes electrogenic Na+/glucose cotransport from the mucosal to serosal side in the small intestine of poultry.

Animals↗

PubMed2006

Effects of feeding deoxynivalenol contaminated wheat on growth performance, organ weights and histological parameters of the intestine of broiler chickens.

A feeding trial was conducted to evaluate the effects of moderate dietary concentrations of deoxynivalenol (DON) during a 21-day feeding experiment on the performance of broilers. Fifteen 1-day-old broiler chicks were randomly divided into two groups. The control group was fed non-contaminated diet. Another group of broilers was fed a diet naturally contaminated with 5 mg DON/kg diet. Deoxynivalenol had no effect (p > 0.05) on feed consumption, feed conversion, body-weight gain, live body weight or mortality. The absolute and relative weight of the organs (gizzard, pancreas, heart, spleen, colon and caecum) were not altered by the dietary inclusion of DON contaminated grain. However, both the absolute and relative weight of small intestine was decreased (p < 0.01) in DON fed broilers compared to the controls. No gross lesions were detected in any of the organs of birds fed contaminated wheat during the feeding trial. The microscopic examination revealed that, the height and the width of villi in duodenum decreased (p < 0.05) in birds fed DON contaminated wheat compared to controls. On the other hand the height and the width of jejunum villi were not affected (p > 0.05). This study indicates that feeding DON for 21 days to broiler chickens at a concentration of up to 5 mg/kg of diet influenced the weight of the small intestine as well as intestinal histology, especially the duodenum, as evidenced by shorter and thinner villi. In conclusion, diets with DON contamination below levels that induce negative impact on health and performance could affect small intestinal morphology in broilers.

Animal Feed↗

PubMed2006

Individual differences and repeatability of post-prandial changes of plasma-free amino acids in young horses.

Few data are available on post-prandial changes of plasma amino acids (AAs) in horses and on the repeatability and the individual variance on different sampling days. The objective of the present study was to measure pre- and post-prandial concentrations of plasma AA in 10 yearling horses. Blood samples were taken on days 1 and 40 of the study before feeding of hay, oats and soya meal and over an 8 h post-prandial period in 2-h intervals. The plasma AAs were measured by high-pressure liquid chromatography after ortho-phthalaldehyde derivatization. Mean fasting concentrations of the AAs were not significantly influenced by the individuum and sampling day. Repeatability of the fasting AA levels in the individual horses on two different sampling days was only found for histidine, 3-methylhistidine, methionine, tryptophan and taurine. While the absolute post-prandial AA concentrations differed between sampling days, the relative changes were comparable. All AA concentrations except 3-methylhistidine increased after feeding by 13% to more than 200% of their fasting values if the combined data of both days were analysed. Four hours after feeding the concentrations of arginine, asparagine, lysine, leucine, isoleucine and threonine, decreased more than 20%. Histidine, methionine, phenylalanine, valine, tryptophan, glutamine, glycine, tyrosine and taurine concentrations decreased by less than 20%. Concentrations of aspartic acid, glutamic acid, ornithine, serine and citrulline remained elevated. Most AA approached the fasting concentrations at 8 h, only glycine increased between 6 and 8 h after meal and 3-methyl-histidine concentrations were constant throughout the entire period. In conclusion, the pre-prandial plasma AA in horses appeared less influenced by individuum or sampling day than post-prandial plasma AA concentrations. Therefore, plasma AA concentrations should be interpreted only under well-defined conditions, especially regarding the feeding regimen.

Amino Acids↗

PubMed2005

In vitro effects of deoxynivalenol on electrical properties of intestinal mucosa of laying hens.

Deoxynivalenol (DON) is common in European cereal grains, and of all the trichothecenes, poses the greatest problems to animal health. The present study investigated the effects of DON on electrophysiological parameters in laying hens' jejunum mounted in Ussing chambers. In vitro studies were performed to measure the effects of different luminal concentrations of DON (0.5, 1, 5, and 10 microg/mL) on the transmural potential difference, electrical tissue resistance, and electrogenic ion flux rates (short-circuit current, Isc) across the isolated gut mucosa. Deoxynivalenol did not alter (P > 0.05) the transmural potential difference. Resistance was higher (P < 0.05) in the tissues exposed to DON compared with basal values. Deoxynivalenol caused a dose-dependent decrease in Isc (P < 0.05). To investigate the mechanism of action of DON, amiloride (a specific inhibitor for Na+ transport) was added after incubation of the tissue with DON. Amiloride did not decrease (P > 0.05) Isc under these conditions. This may indicate that DON inhibited the Na+ transport before addition of amiloride, which did not then show further inhibitory effects. The addition of D-glucose (5 mmol/L) on the luminal side of the isolated mucosa increased (P < 0.05) Isc, and this effect was reversed by phlorizin (a specific inhibitor of sodium/glucose transporter 1), indicating that the glucose-induced Isc increase may be due to Na+-D-glucose cotransport. In our study, DON decreased (P < 0.05) the glucose-induced Isc in a similar way to phlorizin. The remarkable similarity between the effects of phlorizin and DON on electrical properties seemed to be consistent with their common ability to inhibit Na+-D-glucose cotransport. In conclusion, DON decreased the Isc via inhibition of Na+ transport. The effect on intestinal electrical properties was similar to that of phlorizin after addition of glucose, suggesting that DON may inhibit Na+-D-glucose cotransport. The inhibition of Na+ transport and Na+-D-glucose cotransport are important mechanisms of DON toxicity in the intestine of laying hens.

Amiloride↗

PubMed2005

Effects of luminal deoxynivalenol and L-proline on electrophysiological parameters in the jejunums of laying hens.

Most amino acids are cotransported with sodium. Deoxynivalenol (DON) decreases glucose absorption in the chicken small intestine in vivo and in vitro, and this effect is apparently mediated by the inhibition of the sodium D-glucose cotransporter. DON could selectively modulate the activities of other intestinal transporters. In order to assess this hypothesis, a study was conducted to characterize the in vitro effects of DON in the presence of mucosal amino acids, using L-proline as a model, on the electrophysiological parameters in the jejunums of laying hens. L-Proline (mucosal concentration of 1 mmol/L) was added to a stripped proximal part of jejunum sheets mounted in Ussing chambers in Ringer buffer, and the electrical properties were measured. The transmural potential difference (PD) was nearly constant between the treatments. The tissue resistance (Rt) was higher (P < 0.05) in the tissues exposed to DON compared with basal values and the values after addition of L-proline. Addition of L-proline on the luminal side of the isolated mucosa increased (P < 0.05) the short circuit-current (Isc), and it decreased (P < 0.05) after addition of DON, indicating that the proline-induced Isc was altered by DON. The addition of proline after incubation of the tissues with DON had no effect (P > 0.05) on PD or Rt. Proline did not increase the Isc under these conditions. DON decreased (P < 0.1) the Isc after addition of proline, indicating that DON inhibited the Na+-amino acid co-transport. We concluded from the present study that the amino acid cotransporter activity appears to be highly sensitive to DON suppression.

Animals↗

PubMed2005

Early enteral nutrition in young dogs suffering from haemorrhagic gastroenteritis.

The purpose of this study was to investigate clinical and metabolic effects of combined parenteral and oral nutrition compared with parenteral nutrition in young dogs with haemorrhagic gastroenteritis in a prospective clinical study. Dogs with acute gastroenteritis received either parenteral nutrition (group PN, n = 9) or combined parenteral and early enteral nutrition (group EN, n = 10). Infusions were compounded from amino acids, lipids, glucose and electrolyte/glucose solutions [149 g/l glucose, 20 g/l triglycerides, 40 g/l amino acids and 4009 kJ metabolizable energy/l (957 kcal ME/l)], and supplemented with potassium, phosphate and trace elements. Group EN received additionally a hydrolysed diet (74 kJ/kg BW(0.75) on day 2 and 148 kJ/kg BW(0.75) on days 3 and 4). Glucose, triglycerides, protein, albumin, fibrinogen, urea, creatinine, alkaline phosphatase, glutamate dehydrogenase and glutamate pyruvate transaminase were measured before and during the infusions, haematological traits only before the infusions. Statistics included two-factorial anova and subsequent t-test or Wilcoxon test (P < 0.05). All dogs of group EN survived compared with seven of nine patients in group PN. Most dogs in the EN group vomited within half an hour after introduction of oral feeding on day 2 but tolerance for food increased on days 3 and 4. The general health status and faecal and blood parameters of the surviving dogs were similar (P > 0.05) between the groups. In all dogs leucocytes increased during the treatment period, haematocrit and haemoglobin levels declined. Infusions increased blood glucose and triglycerides (P < 0.05); however, no adverse signs were observed. Early enteral nutrition was possible after a short period of adaptation, however, vomiting can be a severe problem. The evaluation of clinical benefits of early enteral nutrition in young dogs with haemorrhagic gastroenteritis requires further investigations.

Animals↗

PubMed2004

Effects of deoxynivalenol on general performance and electrophysiological properties of intestinal mucosa of broiler chickens.

A feeding trial was conducted to evaluate the effects of diets contaminated with deoxynivalenol (DON on the performance of broilers and on the electro-physiological parameters of the gut. The control group was fed the starter and finisher diets without addition of DON. Another group of broilers was fed the starter and finisher diets with 10 mg/kg DON, whereas another group was fed the DON-contaminated diets supplemented with a microbial feed additive (Eubacterium sp.). The diets were provided ad libitum for 6 wk. DON had no effect (P > 0.05) on feed consumption, feed conversion, or body weight. The effect of DON on the electrophysiological parameters of the jejunum was studied in vitro using isolated gut mucosa in Ussing chambers. At the end of the feeding period, 7 birds from each group were killed, and the basal and glucose stimulated transmural potential difference (PD), short-circuit current (Isc), and electrical resistance (R) were measured in the isolated gut mucosa to characterize the electrical properties of the gut. The transmural PD did not differ (P > 0.05) among groups. The tissue resistance was greater (P < 0.05) in birds receiving DON and the microbial feed additive than in the controls and DON group. Addition of D-glucose on the luminal side of the isolated mucosa increased (P < 0.05) Isc in the control and DON-probiotic (Eubacterium sp.; PB) groups, whereas it decreased (P < 0.05) in the DON group indicating that the glucose-induced Isc was altered by DON. Addition of the eubacteria to the DON contaminated feed of the broilers led to electrophysiological properties in the gut that were comparable with those of the control group. It could be concluded that 10 mg/kg DON in the diet impaired the Na(+)-D-glucose cotransport in the jejunum of broilers. In the absence of clinical signs, and without impaired performance, DON appeared to alter the gut function of broilers. The addition of Eubacterium sp. may be useful in counteracting the toxic effects of DON on intestinal glucose transport.

Animal Feed↗

PubMed2003

Simultaneous determination of major B-trichothecenes and the de-epoxy-metabolite of deoxynivalenol in pig urine and maize using high-performance liquid chromatography-mass spectrometry.

A selective analytical method based on high-performance liquid chromatography (HPLC), combined with atmospheric pressure chemical ionisation (APCI-) mass spectrometry (MS), has been developed for simultaneous determination of B-trichothecenes and the major metabolites of deoxynivalenol. The method allows simultaneous analysis of nivalenol (NIV), deoxynivalenol (DON), 15-acetyldeoxynivalenol (15-AcDON), 3-acetyldeoxynivalenol (3-AcDON), fusarenon X (Fus-X) and de-epoxydeoxynivalenol (DOM-1). The method is based on one-step sample clean-up using a multifunctional MycoSep column. A linear gradient mobile phase system, consisting of water:acetonitrile:methanol (H2O:ACN:MeOH) at a flow-rate of 1 ml/min, and a Polar-RP C18 column, were utilised to obtain the best resolution of all tested compounds along with column and equilibrating within 30 min. Dexamethasone (Dex) was used as internal standard. The developed method shows good repeatability for inter- and intra-day precisions as well as good linearity of calibration curves (r2 ranged from 0.9936 to 0.9998). Average recoveries for tested compounds in both matrices have been determined ranging from 63.7 to 102.3% and limit of quantification (LOQ) ranged from 25 to 150 ng/g. The utility and practical impact of the method is demonstrated using contaminated pig urine and maize samples.

Animals↗

PubMed2003

Dietary effects on bifidobacteria and Clostridium perfringens in the canine intestinal tract.

Dietary effects on the intestinal microflora have gained increasing interest because of the evidence that a balanced micro ecology in the gut is important for health and well being. The aim of the present study was to evaluate the effect of different diets on faecal counts of bifidobacteria and Clostridium perfringens in dogs. Two extruded, dry diets, one supplemented with 3% chicory (1.5% inulin), a non-digestible oligosaccharide (NDO) and the other with 3% glucose (GLU) were compared with a protein rich diet (PR+) based on low quality animal derived protein sources (NDO 265, GLU 259, PR+ 726 g crude protein/kg dry matter; greaves meal and bovine lung as protein sources in PR+). Nine adult beagles were subjected to a consecutive cross-over trial. All dogs started with diet PR+, after which groups of four dogs (group A) received GLU and the other five dogs (group B) received NDO. After an intermediate wash-out period with diet PR+ for 3 weeks the A dogs were switched to diet NDO and B dogs to GLU. In the final period all dogs were fed with diet PR+. Faecal samples were collected during each period for dry matter and pH measurements. Faecal bifidobacteria and Cl. perfringens were quantified in fresh samples at the end of each feeding period and additionally on the first days after feed change from the dry diets to diet PR+. Diets NDO and GLU increased faecal dry matter and reduced faecal pH from 6.9 to 7.4 with the high protein diet to 5.9-6.5. The dry diets induced a firmer faecal consistency and a lower faecal pH, with no significant difference between NDO or GLU. Clostridium perfringens was found in all faecal specimens after feeding PR+ with counts of log 8.2-8.8 colony forming units (cfu)/g faeces. Both dry diets reduced the counts of Cl. perfringens significantly (log 3.3-4.0 cfu/g faeces). Switching from the dry diets to the high protein diet induced an increase of Cl. perfringens within 1 day, independent of the previous diet. In dogs fed PR+, bifidobacteria were detected in only four faecal samples and exclusively in the initial feeding period. During the remainder of the experiment the counts fell below the detection limit (log 6 cfu/g faeces). The faecal concentrations of bifidobacteria increased with both dry diets. Slightly higher concentrations (log 9.6-9.7 cfu/g faeces) were obtained from dogs fed the dry diet containing NDO compared with the diet containing glucose (log 9.3-9.4 cfu/g faeces). The increase was small which may be related to the level of total fermentable carbohydrates in both diets which alone increase remarkably the total counts of bifidobacteria. In conclusion, distinct dietary effects on the faecal counts of Cl. perfringens and bifidobacteria with a clear antagonistic pattern were observed. The main factor was the protein source and level in the diet. In this case, NDO favoured the concentrations of bifidobacteria to a limited degree. Further studies are needed to evaluate time effects, metabolic consequences and the potential implication for health promotion in pets.

Animal Feed↗

PubMed2003

Response of dogs to short-term infusions of carbohydrate- or lipid-based parenteral nutrition.

Parenteral nutrition (PN) is used to support intensive care patients. The risk for adverse metabolic effects depends on the composition of infused solutions and the duration of application. The present study in dogs compares metabolic and endocrine effects of two infusion solutions, with either triglycerides or glucose being the major energy sources, administered in a comparatively short infusion period (10 h/day). PN was administered for 9 days to two groups of five adult dogs to meet energy maintenance requirements. In group PN-LIP 61% of the total energy was derived from lipids and 22% from carbohydrates, compared with 21 and 62% in group PN-GLUC. Among routine haematology and clinical chemistry the plasma levels of glucose, triglycerides, insulin, insulin-like growth factor-I (IGF-I), glucagon, 3,5,3'-triiodothyronine and thyroxin were measured in non-infused dogs and at 2, 4, 6, and 8 h after the start of infusion at days 2 and 8 of the study. Infusions protocols did not cause gross metabolic aberrations. During the actual infusions glucose, triglyceride and insulin concentrations were elevated, each depending on the infusion solution. Concentrations of IGF-I, glucagon, 3,5,3'-triiodothyronine, thyroxin and cortisol did not change significantly. In conclusion short infusion periods of 10 h per day were tolerated by healthy dogs without adverse signs, which could improve practicability of PN also in clinical cases.

Animals↗

PubMed2002

[Efficacy of probiotic feed additives: guidelines for the evaluation of the efficiency of microorganisms in dogs, cats, and horses].

Probiotic microorganisms are frequently in use as feed additives for farm and pet animals. For admission for the common market products have to be tested according to the feed additive directive 70/524/EC. The dossier for admission has to comprise data of efficiency as laid down in the directive 87/153/EC. During the last years it became obvious after the evaluation of several dossiers, that no definitive criteria for the assessment of efficacy were available for dogs, cats and horses (84/153/EC). Aspects like the promotion of animal production are not relevant in this context. Therefore, the European commission launched the directive for the evaluation of efficacy of microorganisms for dogs, cats and horses, that supports the evaluation of microbial feed additives and which is described in this paper.

Animal Feed↗

PubMed2002

[Animal-derived feedstuffs as possible vectors for bovine encephalopathy (BSE) in Germany. Part 2: Assessment of vector risk for compounded feed].

Specific conditions and practices of cattle feeding in Germany have to be taken into account for assessing the risk of feed born transmission of bovine spongiform encephalopathy, especially regarding the situation before the year 2000 when specific directives were introduced for feed production. The present retrospective epidemiological study includes data on feed production and the estimated amount of animal derived feedstuffs for the production of compounded feed for cattle. Risk assessment was performed based on the 'reproduction rate' (R0), that is defined as the estimated number of infections resulting from the processing of brain and spinal cord of BSE affected cattle that is recycled to bovines via feed. Under the conditions as given in Germany until the year 2000 the reproduction rate of BSE via the inclusion of animal derived feedstuffs in compounded feed production for cattle was estimated to be 1.1. Thus, it can be expected that BSE could be reproduced in the system, but with comparatively low efficiency. The expected incidence of BSE should be considerably lower compared to the situation during the 90th in the UK, due to the markedly lower recycling rate of animal protein in cattle feeding. Animal fat could have been a significant factor for BSE transmission due to contamination by proteinaceous brain and spinal cord material during the production process. The relative significance of fat containing feedstuffs for BSE transmission could have been higher in Germany compared to the situation in the UK where meat and bone meal was produced under different conditions and frequently used in higher proportions as an ingredient for compounded feed for ruminants.

Animal Feed↗