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1. One growth experiment and one balance test were conducted to study the response to increasing levels of dietary lysine supplementation in male Pekin ducks with special reference to the growth periods from 1 to 3 weeks and 4 to 7 weeks of age. 2. Two different low-lysine diets were used as basal diets in both periods. The basal lysine levels were 7.6 g/kg (d 1 to 21) and 6.2 g/kg (d 22 to 49) and the ranges in lysine concentration were 7.6 to 12.6 g/kg (d 1 to 21) and 6.2 to 11.2 g/kg (d 22 to 49). 3. Growth performance, feed conversion efficiency and meat yield increased (P < 0.05) with increasing lysine concentration (requirement defined as 95% of the asymptote). 4. It is concluded that the dietary lysine concentration should be 0.93 g/MJ nitrogen corrected apparent metabolisable energy (AMEN) (11.7 g/kg) for the starter period (until d 21) and 0.75 g/MJ AMEN (10.0 g/kg) for the grower period (from d 22 onwards).

Effects of a supplementation of 80 mg L-carnitine per kg diet were studied in broiler chicken at two dietary levels of fat (4 and 8%) and different feeding levels (ad libitum in a growth trial, 95 and 85% of ad libitum in a balance trial). A low-carnitine basal diet adequate in amino acid concentration was used. In the growth trial, each diet was fed to 9 groups of 10 birds each for 16 days from day 5 of live onwards. Growth and feed intake were determined. At the end of the trial, birds were killed and homogenised for subsequent empty body analysis. Accretion of protein and energy was determined using a representative blank group killed at the beginning of the trial. In the balance trial, 8 individual birds were used per treatment. Birds were offered the feed at approximately 85 and 95% of ad libitum intake, which was determined with separate birds for both fat levels. Excreta were quantitatively collected three times daily for 8 consecutive days beginning on day 17 individually for each bird. Supplemented L-carnitine did not significantly affect any response criterion. However, growth and feed conversion tended to be improved by about 5% in the carnitine supplemented diets when fed ad libitum. An interaction between carnitine and fat level occurred with regard to feed conversion, indicating that carnitine had a positive effect at the high fat level, but not at the low fat level. L-carnitine did not positively affect the metabolisability of energy (ME/GE) and the efficiency of energy utilisation (RE/GE or RE/ME). Similarly, no significant carnitine effect was determined with regard to N accretion and the efficiency of utilisation of dietary protein in both trials. It is concluded that endogenous carnitine synthesis is not the limiting factor for energy utilisation in broiler chicken, even at high dietary fat concentration. Occasionally reported positive effects of supplemental carnitine were likewise caused by reasons other than improved energy or protein utilisation. Further studies on amino acid utilisation and catabolism should consider marginal amino acid supply.

Four experiments were conducted with a total of 2288 pekin ducks. Day-old ducklings were group-penned on straw bedding and were fed complete, pelleted diets ad libitum for up to 49 days depending on experiment. In each experiment, starter diets (until day 21) and grower diets (from day 22) were used adequate in ME content and nutrient content. The sum of wheat, rye, and triticale amounted to at least 57% (starter diet) and 63% (grower diet), respectively. The inclusion level of wheat, rye, and triticale was different between experiments, with a maximum rye inclusion of 45%. Five different enzyme preparations all having, 1,4-beta-xylanase as the main activity were considered in this study with either one (2 preparations) or three (3 preparations) levels of supplementation. The effect of enzyme supplementation on ileal digesta viscosity was studied at the end of two experiments comprising 4 enzyme preparations. A significant reduction in digesta viscosity was determined for all preparations. The viscosity of digesta was higher in birds that were fed 45% rye in their diet as compared to those fed a diet based on triticale and wheat, even with enzyme supplementation. Differences in digesta viscosity were not reflected in growth or feed conversion data. In one experiment, the body weight of ducks on day 21 was significantly improved by enzyme supplementation. This effect disappeared with progress in experiment. In another experiment, feed intake was significantly improved with enzyme supplementation. Apart from this, no statistically significant improvement in performance could be detected. On overall average, the final BW of ducks fed an enzyme was (as compared to the unsupplemented control = 100), 100, and the feed conversion ratio was 101. There is no indication from the growth and feed conversion data that an enzyme effect becomes more pronounced with increasing inclusion rate of soluble NSP by rye. It is concluded that supplementary xylanases are efficient in reducing digesta viscosity in ducks fed diets with high inclusion of wheat, rye and triticale. No consistent effect of enzyme supplementation, however, can be expected on growth and feed conversion.

During treatment of four type-1 diabetics (aged 20-46 years) by continuous subcutaneous insulin infusion (CSII) a leak developed in the system which caused severe ketoacidosis. The gastrointestinal symptoms (nausea, vomiting and abdominal pain) were misdiagnosed by both the patients and their doctors because there was only mild hyperglycaemia. These observations highlight the importance of carefully instructing and supervising patients at the beginning of CSII and point to the need of frequent urine testing by the patients, also for urinary keto bodies.

Male chickens of a broiler (B) and a layer (L) genotype were grown in floor pens from d 8 to 21 posthatch in groups of 10. Three pens per genotype were allocated to each of 10 experimental diets. The diets were offered ad libitum and they differed in lysine concentration from 3.8 to 16.8 g/kg. The source of supplemental lysine was L-lysine x HCl. All birds were killed at the end of the experiment, and representative birds (3 groups of 10 per genotype) were killed at the start for baseline measurements. Accretions of protein, fat, energy, and amino acids were determined by comparative body analysis. Responses were described with sigmoidal and exponential functions. Additionally, the net disappearance rate (NDR) of amino acids from the small intestine was studied with the basal diet (3.8 g of lysine/kg) using 6 replicated pens of 15 birds per genotype. Titanium dioxide was the indigestible marker. Net disappearance rates were not significantly different between genotypes for CP or any amino acid. Responses to incremental lysine concentration were nonlinear for both genotypes but distinctly different in magnitude between genotypes. Estimated y(max) values for 14-d BW, protein gain, and gain/ feed ratio were 534 (B) and 153 (L) g, 87.1 (B) and 28.7 (L) g, and 0.82 (B) and 0.71 (L) g/g. Protein accretion approached 95% of the estimated y(max) with dietary lysine concentrations of 12.5 (B) and 10.4 (L) g/kg. The amino acid profile of accreted whole body protein was different between genotypes, and was affected by supplementary lysine. Lysine content in accreted whole body protein approached upper values of 7.4 (B) and 5.6 (L) g/16 g of N with increasing dietary lysine concentration. Marginal efficiency of lysine utilization, determined as delta lysine accretion/delta lysine intake, showed maxima of 99% (B) and 74% (L). These maxima were achieved at intakes which were much lower than those needed for high protein accretion. It was concluded that the efficiency of amino acid utilization may depend on genotype, perhaps due to differences in the relative proportion of different protein fractions to whole body protein and due to differences in the ratio of synthesis and degradation of body proteins. Nonlinear relationships and different amino acid pattern of accreted body protein should be implemented in future models of requirements.

1. An experiment was conducted to investigate whether a linear regression approach is a suitable tool for determining the amino acid (AA) digestibility up to the terminal ileum of broiler chickens. Solvent-extracted rapeseed meal (RSM) was used as the model ingredient. 2. Ten diets with 5 different inclusion rates of RSM (60, 120, 180, 240 and 300 g/kg, corresponding to crude protein concentrations from 170 to 250 g/kg in the diet), each without or with a supplementation of phytase (500 U/kg), were fed ad libitum to broiler chickens between 14 and 21 d of age. Seven pens of 12 chickens were allocated to each treatment. Digesta were sampled on a pen basis from the section of the gastrointestinal tract between Meckel's diverticulum and 2 cm anterior to the ileo-caeco-colonic junction. Titanium dioxide was included as an indigestible marker. 3. The amounts of crude protein and AAs digested up to the terminal ileum constantly increased with increasing AA intake over the entire range of intakes. When the amount of an AA digested at the terminal ileum is linearly regressed against its intake, the deviation of the slope from 1 is caused by both the unabsorbed AA from RSM and from specific endogenous losses related to RSM. These slopes varied between 0.68 and 0.88 for individual AAs, and the slopes were unaffected by phytase supplementation. 4. It is suggested that a linear regression approach be adopted to study the AA digestibility of raw materials in chickens. Digestibility determined this way does not need any correction for basal endogenous loss.

The response of White Pekin ducks to supplements of L-valine was studied during 3 wk posthatching. The basal valine concentration was 6.8 g/kg in a diet containing 18% CP and 2,990 kcal ME/kg (12.5 MJ ME/ kg). L-valine was supplemented in eight graded levels up to 12.7 g/kg at the expense of L-glutamic acid. Three pens of 14 ducks were allocated to each valine level. Diets were offered ad libitum. Body weight gain and feed/gain ratio were studied. At the end of wk 3, ducks were killed, processed to a homogenous mass, and analyzed for total body CP and amino acid content. Accretion of protein and amino acids was calculated. Additionally, a 5-d N balance study was conducted with separate ducks of the same hatch beginning on d 11 (6 ducks per treatment). The response of ducks to increasing valine concentration was described by exponential functions. Ducks significantly responded to the increasing valine concentration in growth, feed/gain ratio, and protein accretion. Ninety-five percent of y(max) in BW gain and protein accretion were achieved with 8.0 and 7.9 g valine/kg, respectively. The content of protein in gained BW was, on average, 149 g/kg without a significant valine effect. The valine content in accreted body protein was also unaffected by dietary valine (4.1 g/16 g N on average), which suggested that a major shift in body protein fractions did not occur. The overall efficiency of valine utilization was affected by dietary valine concentration and showed a maximum of 49%. Data from the balance study showed basically the same response of ducks, but the estimated optimum in dietary valine concentration was lower (7.0 g/kg). A comparison with published broiler data indicated that ducks and broilers in this age period were similar with regard to the valine content in gained protein and the efficiency of utilization of supplemented valine.

A 3 x 2-factorial balance trial was conducted with dietary concentrations of P below the requirement (3.6, 4.3 and 5.0 g/kg DM) and Ca below or at the requirement (28 and 37 g/kg DM) adjusted by monobasic calcium phosphate (MCP, Ca(H2PO4)2) and calcium carbonate (CaCO3). The diets were mainly based on maize and soybean meal. Six 18-week old laying hens were allocated to each of the diets, and excreta were quantitatively collected for 21 days from week 22 of age onwards. Feed allowance was 95 g/d according to pre-treatment ad libitum intake of the hens receiving the lowest P concentration. After the balance trial was terminated, ileal digesta was obtained from each hen, and the flow at the terminal ileum was calculated using TiO2 as indigestible marker. Linear regression analysis was applied to determine the effect of supplementary P. Hens were in a negative energy balance, indicated by a loss in BW across all treatments. Intake and excretion of both N and energy were not significantly affected by the P or Ca content of the diet. P from supplemented MCP was almost completely recovered in excreta, irrespective of dietary Ca concentration. At the terminal ileum, however, the P flow was not significantly affected by the MCP supplementation. Net absorption of P from MCP was almost complete until the terminal ileum, but P was re-directed into the excreta, likewise via the urine. The supplementation of Ca reduced praecaecal net absorption and utilisation of P from the basal diet, likewise due to a reduced phytate hydrolysis. It is suggested by the data, that comparative measurements of P availability for laying hens should be conducted on the basis of praecaecal net absorption rather than on total excretion measurements.

Obstruction of infusion sets is a major cause of metabolic deterioration or even ketoacidosis during continuous subcutaneous insulin infusion (CSII). 21 type I, CSII-treated patients were studied in a prospective, randomized cross over design during two periods of three months to assess the effects of Genapol stabilized human insulin (HOE 21 PH H-TRONIN) on obstruction frequency of PVC catheters in comparison with a neutral preparation of biosynthetic human insulin (BHI). In a total observation time of 9.5 patient-years 79 catheter obstructions by precipitated insulin occurred with an incidence of 0.67 episodes per patient-month for BHI and 0.026 for HOE 21 PH. Improvement of metabolic control paralleled the reduction of obstruction frequency by HOE 21 PH. Thus, a stabilized insulin preparation is recommended for use in CSII to reduce the therapeutic risk.

Biliary concentrations of a new cephalosporin, ceftizoxime, were measured in bile collected in 8 cholecystectomized patients provided with T-tube drainage and in 14 patients where bile was obtained by puncture of the gall bladder and choledochus during cholecystectomy. In patients with external biliary drainage, a mean biliary peak of 150.3 +/- SEM 49.8 micrograms/ml has been observed 2 h after intravenous injection of 2 g of ceftizoxime; the antibiotic activity amounted still to 17.3 +/- 6.0 micrograms/ml after 6 h. Assays performed during operation showed the following simultaneous concentrations 1 h after 2 g of ceftizoxime given intravenously: serum: 85.3 +/- 8.1 micrograms/ml; main duct bile: 279.8 +/- 40.0 micrograms/ml; gallbladder bile: 119.9 +/- 19.4 micrograms/ml. These findings were compared with the biliary excretion of 8 other cephalosporins studied previously under the same conditions. The results of the present study suggest that administration of ceftizoxime may be effective in the treatment of biliary tract infections.

Basic expressions are derived for the relationships between excitation current, speed, and torque of an eddy-current coupling with a solid iron eddy-current member. This paper is concerned only with eddy-current couplings of the inductor or unidirectional flux type; however, the method has been applied also to other types of eddy-current machinery. Necessary approximations are made for the theoretical analysis, and a 5-step procedure is used to develop the resulting relationships.

Serum concentrations and urinary recovery of ceftizoxime were investigated in 18 healthy volunteers. The substance was given as a bolus (2 min) i.v. injection. In volunteers the injection was preceded by orally administered probenecid, 500 mg, 7 and 1 h before (Group II); the remaining 12 volunteers received medication. 5 min after the injection, the serum concentration in Group I was 107 +/- 22 micrograms/ml and in II 93 +/- 18 micrograms/ml in the mean; 30 min after the injection in I 45 +/- 8 micrograms/ml and 44 +/- 10 micrograms/ml in II. The further of the serum concentration was slower in II than in I: serum concentration 6 h after the injection was 2.6 +/- 0.9 micrograms/ml in I and 4.4 +/- 2 micrograms/ml in II. During the first 8-h period 81% of the administered cephalosporin was recovered in the urine of I and 58% in the urine of II. t/2 beta was calculated for I with 1.76 h and 2.13 h for II. The distribution volume was equal, so that the differences in serum concentrations could be explained by the reduced renal clearance: from 2.1 to 1.4 ml/s. Because the comparison was done with two independent groups and furthermore only 6 volunteers participated in the probenecid group, only the difference in the urine in the first 2 h was statistically significant.

During treatment of four type-1 diabetics (aged 20-46 years) by continuous subcutaneous insulin infusion (CSII) a leak developed in the system which caused severe ketoacidosis. The gastrointestinal symptoms (nausea, vomiting and abdominal pain) were misdiagnosed by both the patients and their doctors because there was only mild hyperglycaemia. These observations highlight the importance of carefully instructing and supervising patients at the beginning of CSII and point to the need of frequent urine testing by the patients, also for urinary keto bodies.

110 type I diabetic patients were treated with CSII from 1980 to the end of 1988 on a routine basis over a total of 337 patient years and a mean of 36.7 months per patient. 14 cases of severe diabetic ketoacidosis (DKA) were seen in 14 patients representing an accumulated incidence of one episode of DKA per 209 patients months. DKA occurred on an average of 25 months after start of CSII therapy. The main causes of DKA were undetected leakage of the infusion system in nine, infection in three and mismanagement of the pump in two cases. Technical or electronic failures could be excluded in each case. The lack of checking urine for ketones, the wrong feeling of safety after long-term successful pump treatment, and a concomitant psychological stress situation favoured the misjudgement of the clinical symptoms of ketosis and the delay of hospital admission.

An enzyme preparation capable to reduce dihydrofolic acid to tetrahydrofolic acid, was prepared from liver and brain of rats. Using a spectrophotometric method the reaction rates of these preparations were determined. For rat liver dihydrofolic acid reductase K m was found to 2×10−6 M for NADPH + H+ and 1.8×10−6 M for FH2. Rat brain dihydrofolic acid-reductase has a K m of 8×10−6 M for NADPH + H+. Folic acid was shown to be a competitive inhibitor of the conversion of dihydrofolate to tetrahydrofolate. With 3-APADPH + H+ which is formed in brain of rats after application of 3-acetylpyridine, the enzyme activity of both preparations was found to be significantly decreased. These observations are discussed in relation to the functional impairment of rats treated with 3-acetylpyridine.

The effects of a supplementation of P from monobasic calcium phosphate (MCP; Ca(H2PO4)2) to low-P basal diets were studied in growing Pekin ducks. Body weight gain and feed conversion were studied in two separate periods between Days 1 to 21 (Experiment 1) and between Days 21 to 49 (Experiments 2 and 3). Retention of P was measured by comparative slaughter technique in Experiment 1. Additionally, two balance trials with quantitative determination of intake and excretion of P were conducted between Days 12 to 17 and between Days 30 to 35. MCP was supplemented in 7 or 6 graded levels at the expense of sand. In cases when ANOVA showed a significant effect of MCP supplementation, the response of ducks was described by nonlinear functions. No significant effect of supplemental MCP on growth, feed intake or feed/gain ratio was detected in the period between Days 21 and 49 with a basal P level of 3.0 g/kg. Between Days 1 and 21, ducks needed 5.1 g P/kg diet to achieve 95% of ymax in BW gain. The ymax for P concentration in gained BW, determined from balance trials, was 5.6 and 5.1 g/kg between Days 12 to 17 and Days 30 to 35, respectively. Ninety-five percent of ymax in P retention was achieved with a dietary P concentration of 6.2 and 4.3 g/kg between Days 12 to 17 and Days 30 to 35. The cumulative efficiency of utilization (retention/intake x 100) of dietary P from the basal diet was 49% (Days 12 to 17) and 43% (Days 30 to 35), and approached maximum with increasing supplementation of MCP of 55 and 53%, respectively, before it decreased again with further increase in MCP supplementation. The marginal efficiency of supplemental P (deltay/deltax) showed a maximum of 86% (Days 12 to 17) and 92% (Days 30 to 35), and this maximum was achieved where only 75 and 72% of ymax in P retentions were achieved. It is concluded that ducks require a lower P concentration in the diet with increase in age, but that the efficiency of utilization of P from inorganic salts is not clearly affected by age. Conclusions regarding the P requirement largely depend on the response criterion chosen. Based on P retention data, a dietary level of available P is recommended to be 3.4 (Days 1 to 21) and 2.3 g/kg (Days 21 to 49), although growth was unaffected by P even at lower concentrations of available P. Future comparative studies on the availability of P from ingredients should be conducted at a dietary P concentration that allows for identifying the maximum in utilization.