Resorcylic acid lactones in urine samples of slaughtered animals resulting from potential feed contamination with zearalenone.

Resorcylic Acid Lactones, including zeranol, anabolics listed in the group A4 of Directive 96/23/EC, are banned in Europe for use in animals since 1985. Zeranol, after administration to animals, is metabolized to taleranol and zearalanone. It can also naturally occur in the urine due to conversion of zearalenone that may be present in animal feed. In 2010-2017, in Poland, 7746 animal samples were tested for zeranol residues within the official monitoring program. In 13, zeranol was detected after screening. Re-examinations confirmed resorcylic acid lactones in six samples. The recommendations state that only the presence of zeranol and/or taleranol gives the basis for non-compliance. Confirmation should cover the entire profile of six resorcylic acid lactones. In case of detection, the relationship ratio should be verified. Following the proposed criteria, it could be concluded that zeranol detected in urine samples in Poland originated from contamination of feed with mycotoxin, not from illegal use.

Comparison of xenobiotic metabolism in phase I oxidation and phase II conjugation between rats and bird species.

There have been many reports regarding toxic chemicals in birds. Chemicals are mainly metabolized in the liver through phase I oxidation by cytochrome P450 (CYP) and phase II conjugation by conjugated enzymes, such as UDP-glucuronosyltransferase (UGT), sulfotransferase (SULT), glutathione-S-transferase (GST), etc. Xenobiotic metabolism differs among bird species, but little detailed information is available. In the present study, the four-ring polycyclic aromatic hydrocarbon (PAH), pyrene, was used as a model xenobiotic to clarify the characteristics of xenobiotic metabolism in birds compared with laboratory animals by in vivo and in vitro studies. Plasma, bile, and excreta (urine and feces) were collected after oral administration of pyrene and analyzed to clarify xenobiotic metabolism ability in chickens and quails. Interestingly, pyrenediol-glucuronide sulfate (PYDOGS) and pyrenediol-diglucuronide (PYDOGG) were present in chickens and quails but not in rats. In addition, the area under the curve (AUC), maximum plasma concentration (Cmax), and time to maximum plasma concentration (Tmax) of pyrene-1-sulfate (PYOS) were higher than those of the parent molecule, pyrene, while the elimination half-life (t1/2) and mean residence time (MRT) were faster than those of the parent pyrene. With regard to sulfation of 1-hydroxypyrene (PYOH), the maximum velocity (Vmax) and Michaelis constant (Km) of rat liver cytosol were greater than those of chicken and quail liver cytosol. Furthermore, Vmax/Km of UGT activity in rat liver microsomes was also greater than those of chicken and quail liver microsomes. Characterization of xenobiotic metabolism revealed species differences between birds and mammals, raising concerns about exposure to various xenobiotics in the environment.

Calcium particle size effects on plasma, excreta, and urinary Ca and P changes in broiler breeder hens.

An experiment was conducted using non-colostomized and colostomized broiler breeder hens to determine the effects of feeding limestone of 2 different mean particle sizes (185 microns and 3490 microns) on P excretion, total P and Ca retention, and urinary P and Ca excretion during a 6-week feeding study. Additionally, changes in plasma inorganic P (iP) and ionic Ca (Ca++) and urinary excretion of P and Ca were determined in one egg laying cycle of 24 hours. One-hundred-fifty non-colostomized and 6 colostomized broiler breeder hens, 30 wk of age, were divided into 2 groups and fed broiler breeder diets supplemented with either small particle or large particle limestone. Two % acid insoluble ash (Celite) was added to the feed as a marker. Diets, excreta, and urine samples were analyzed for total P and Ca by ionic coupling plasma (ICP) analysis. The non-colostomized breeders fed large particle limestone compared to small limestone particles produced a significant increase in percent tibia ash (P < 0.0001) and egg specific gravity (P = 0.0382), but P excretion approached a tendency of being reduced (P = 0.1585). The urinary total P and Ca (∼18 and 9%, respectively) of total P and Ca excretion for breeders fed both sizes of limestone was not significantly different in the colostomized breeders. In plasma, both iP and Ca++ reached a peak during 18 to 20 h and 20 to 24 h post oviposition for smaller and larger particle sized limestone fed groups, respectively. The maximal excretion of urinary P was found during 11 to 20 h post oviposition, whereas urinary Ca peaked during 0 to 11 h post oviposition for both smaller and larger particle sized limestone supplemented groups. In summary, the findings indicate that the particle size (smaller and larger) of calcium source did not significantly influence the quantitative total urinary excretion of Ca and P but did influence the timing of Ca and P excretion.

Metabolism and Disposition of Aditoprim in Swine, Broilers, Carp and Rats.

Aditoprim (ADP) is a newly developed antibacterial agent in veterinary medicine. The metabolism and disposition of ADP in swine, broilers, carp and rats were investigated by using a radio tracer method combined with a radioactivity detector and a liquid chromatography/ion trap/time-of-flight mass spectrometry. After a single oral administration, more than 94% of the dose was recovered within 14 d in the four species. The urine excretion was dominant in swine and rats, making up 78% of the dose. N-monodesmethyl-ADP, N-didesmethyl-ADP, and 10 new metabolites were characterized. These metabolites were biotransformed from the process of demethylation, α-hydroxylation, N-oxidation, and NH2-glucuronidation. After an oral dose for 7 d, ADP-derived radioactivity was widely distributed in tissues, and high concentrations were especially observed in bile, liver, kidney, lung, and spleen. The radioactivity in the liver was eliminated much more slowly than in other tissues, with a half-life of 4.26, 3.38, 6.69, and 5.21 d in swine, broilers, carp, and rats, respectively. ADP, N-monodesmethyl-ADP, and N-didesmethyl-ADP were the major metabolites in edible tissues. Notably, ADP was detected with the highest concentration and the longest duration in these tissues. These findings indicated that ADP is the marker residue and the liver is the residue target tissue.

The use of near-infrared reflectance spectroscopy to predict the moisture, nitrogen, calcium, total phosphorus, gross energy, and phytate phosphorus contents of broiler excreta.

One hundred forty-three broiler chick excreta samples were obtained from previous experiments dealing with phytate phosphorus utilization. The air-dried samples were ground in a Cyclotech 1093 sample mill and analyzed for the following: moisture, N, Ca, energy, total P, and phytate P. By chemical assay, the sample compositions were moisture: mean = 9.62, SD = 1.27% (range = 7.37-13.59); N: mean = 5.31, SD = 0.37% (range = 4.28 to 6.48); Ca: mean = 1.66, SD = 0.32% (range = 0.85 to 2.6); total P: mean = 1.13, SD = 0.28% (range = 0.66 to 1.75); gross energy: mean = 3,560, SD = 120 kcal/kg (range = 3,309 to 3,882); phytate P: mean = 0.63, SD = 0.17% (range = 0.32 to 0.97). The samples were scanned in a Feed & Forage Analyzer Model 5000 with near-infrared reflectance spectroscopy (NIRS)-2 Software. One hundred twenty-three samples were used to create the calibration curves (20 randomly selected samples were set aside for validating the calibration). The combination of math treatments and scatter corrections that provided the best standard error of cross validation (and its correlation coefficient) was chosen for the standard curves. The coefficients of determination (R2) were moisture, 0.96; N, 0.88; Ca, 0.84; total P, 0.91; gross energy, 0.86; and phytate P, 0.86. The standard errors of prediction were moisture, 0.342%; N, 0.193%; Ca, 0.143%; total P, 0.134%; gross energy, 74.66 kcal; and phytate P, 0.91%. We concluded that it is possible to predict the moisture, N, Ca, gross energy, total P, and phytate P in broiler excreta by using NIRS.

Reduced dietary phosphorus levels for layers.

Two experiments were undertaken to study the response of White Leghorn hens to low dietary phosphorus levels from 18 to 64 wk of age. A corn-soybean meal diet containing .2% available phosphorus gave similar performance, up to 32 wk of age, as a similar control diet containing .4% available phosphorus. Beyond 32 wk, although shell quality and average egg weight were similar, egg production was significantly reduced with the lower phosphorus diet. Phosphorus excretion (grams per bird per day) averaged .47 g for .4% vs .28 g for .2% available phosphorus when measured at 28 wk of age. In a second experiment identical procedures and bird number as used in Experiment 1 were employed with the exception that the test diet contained .3% rather than .2% available phosphorus. No differences were noted for any of the production variables measured between the .4 and .3% available phosphorus diets. Phosphorus excretion data collected at 25, 32, 44, and 60 wk of age showed a decrease of approximately 20% for hens receiving the lower phosphorus diet. Indeed the overall average for phosphorus excretion for the lower phosphorus diet was calculated to be identical to the 20% lower total phosphorus content of this diet (.59 vs .47%).

Hypercalciuric response to dietary supplementation with DL-methionine and ammonium sulfate.

Renal Ca and inorganic P (Pi) excretion were evaluated in Single Comb White Leghorn pullets reared on diets containing 1 or 3.5% Ca alone or supplemented with .6% DL-methionine or .53% ammonium sulfate. Plasma and urine samples were collected during a CONTROL period, and while 200 mM Ca was infused intravenously (Ca-LOADING). Excess Ca, whether supplied chronically in the feed or infused acutely into birds fed 1% Ca diets, significantly reduced glomerular filtration rates, effective renal plasma flow rates, and Pi excretion rates and significantly increased Ca excretion rates and urine pH. Birds fed diets supplemented with DL-methionine and ammonium sulfate maintained significantly lower plasma Ca concentrations during the CONTROL and Ca-LOADING periods than birds fed the respective 1 or 3.5% Ca basal diets. When compared with birds fed the respective 1 or 3.5% Ca basal diets, birds fed the 1% Ca diet supplemented with ammonium sulfate or the 3.5% Ca diet supplemented with DL-methionine had significantly higher absolute urinary Ca excretion rates during Ca-LOADING. Fractional Ca excretion during Ca-LOADING was significantly higher in birds fed 3.5% Ca supplemented with DL-methionine or ammonium sulfate than in birds fed the 3.5% Ca basal diet. These results indicate that DL-methionine and ammonium sulfate accelerated urinary Ca excretion and reduced Ca retention in the extracellular fluid. The hypercalciuric efficacies of DL-methionine and ammonium sulfate were revealed only when the filtered load of Ca was increased through intravenous Ca infusions.

A detailed colostomy procedure and its application to quantify water and nitrogen balance and urine contribution to thermobalance in broilers exposed to thermoneutral and heat-distressed environments.

A surgical procedure for the separation of avian urinary and fecal excrement, in birds as young as 3.5 wk of age, was developed and used to quantify ambient temperature effects on urine production and composition. The colostomized broilers were used in two experiments to estimate urine production, osmolality, and contribution to water, nitrogen, and thermobalance of birds exposed to thermoneutral (24 C, TN) and heat-distressed (35 C, HD) environments. Urine production averaged over three 12-h periods was greater (P < .05), at 101 versus 51 mL/12 h per kilogram of BW and osmolality lower (P < .05) at 142 versus 220 mOsm/kg urine during HD and TN, respectively, in Experiment 1; and averaged over one 12-h period 82 versus 32 mL/12 h per kilogram of BW and 136 versus 208 mOsm/kg in Experiment 2 for HD and TN, respectively. In Experiment 1, urine production per milliliter of water consumed was increased (P < .05) by HD during Periods 2 and 3 even though in both experiments the values were similar during the first 12 h. Both urinary nitrogen and osmolar losses were increased (P < .05) by 50 and 89.2%, respectively, during HD, but without effect on fecal nitrogen. Evaporative cooling of broilers was increased (P < .05) by 154% during HD. These studies provide a well-defined colostomy procedure and suggest that broiler urine production and composition as well as overall thermobalance, water, and nitrogen balance are strongly impacted by acute HD.

Occurrence of intraportally-infused urea-15N in the urine of domestic fowl.

1. Measurements were made in situ to determine the occurrence of intraportally infused urea-15N in ureteral urine of the fowl. 2. Of the total amount of infused urea-15N, 15% was excreted intact into the urine (90% of urinary total 15N) whereas 9% remained unchanged in the blood (78% of blood non-protein-15N). 3. The proportions of non-protein-15N in the blood, liver and kidney were 12, 3 and 1%, respectively of the infused 15N. Protein-15N was 3% of that infused in blood and much less in liver and kidney. 4. About 1% of the infused 15N was observed in the urinary uric acid, and 3% of the infused 15N in non-protein N, other than urea, ammonia and glutamine amide N, of blood and liver. 5. No appreciable amounts of 15N were present in ammonia and glutamine amide N of blood, liver or kidney and in uric acid of liver or kidney. 6. The caecal contents contained about 1% of the infused 15N with 15% of this as ammonia-15N. 7. It is concluded that intraportal urea is mostly excreted unchanged into ureteral urine of the fowl.

Influence of dietary cholecalciferol, calcium, and phosphorus on urinary calcium in commercial Leghorn hens.

An experiment was conducted to determine the influence of various dietary levels of cholecalciferol, Ca, and P on urinary Ca and pH, and on plasma concentrations of inorganic P (Pi) and total Ca (TCa) in commercial Leghorn hens. All hens were fed a layer diet containing 500 ICU of cholecalciferol/kg for 30 days and then allocated equally to treatment diets. Twelve treatment diets were in a 3 x 2 x 2 factorial arrangement that comprised three levels of cholecalciferol (0, 2,200, and 4,400 ICU/kg), two Ca levels (3.75 and 5.75%) and two P levels (.3% and .7%). After 9 days of feeding, blood (12 hens per time per treatment) and urine (6 hens per time per treatment) were sampled at 8 and 16 h after oviposition. Urinary Ca and plasma TCa concentrations increased (P less than .05) when dietary cholecalciferol level was increased from 0 to 2,200 ICU/kg, but did not change when cholecalciferol was increased from 2,200 to 4,400 ICU/kg. High levels of dietary Ca elevated (P less than or equal to .05) the urinary Ca concentration of hens fed the low-P treatments. Low levels of dietary P reduced plasma P and increased urinary Ca and pH at all levels of cholecalciferol and Ca; however, the magnitude of increases in urinary Ca were not uniform across all levels of cholecalciferol and Ca. Increases in urinary Ca resulting from low dietary P were relatively small when the diet lacked cholecalciferol, but was increased three- to fourfold when the diet contained adequate or excess levels of Ca and excess but not toxic levels of cholecalciferol.

Ileal digestibility and urinary excretion of D-xylose and L-arabinose in ileostomized adult roosters.

An experiment with ileostomized adult roosters was conducted to determine the ileal digestibility and urinary excretion of D-xylose and L-arabinose. As a reference, D-glucose was included in the experiment. The sugars were tested at graded dietary levels of 2.5, 5.0, 7.5, and 10.0%. Mean ileal digestibility of D-glucose and D-xylose was nearly 100%. Ileal digestibility of L-arabinose decreased linearly (P less than .05) with increasing dose level. The corresponding ileal digestibilities for L-arabinose at dietary levels of 2.5, 5.0, 7.5, and 10.0% were 95.5, 93.6, 80.3, and 74.6%. Both pentose sugars were partly excreted in the urine. The extent of this urinary excretion in percentage of intake increased linearly (P less than .05) as the dietary level increased. In roosters fed the 2.5% D-xylose diet, 7.2% of the D-xylose consumed appeared in the urine. This level increased to 20.2% when roosters were fed a diet containing 10.0% D-xylose. Corresponding values for L-arabinose at these dietary inclusion levels were 8.7 and 16.6%.

Influence of dietary calcium and phosphorus on urinary calcium in commercial leghorn hens.

An experiment was conducted to determine the influence of dietary Ca (2, 4, and 6%) and P (.3 and .6% total) on urinary Ca and pH and on plasma Ca++ and inorganic P (Pi) in commercial Leghorn hens. Urine (six hens per treatment) or blood (eight hens per treatment) was collected from hens at 0, 7, 14, and 21 h postoviposition on Days 3 and 10 after its introduction to treatment diets. Low dietary P reduced (P less than or equal to .05) plasma Pi concentrations. The lowest concentration of dietary Ca reduced (P less than or equal to .05) plasma Ca++. Urinary pH and Ca were lowest at 14 h after oviposition. Increasing dietary Ca from 4 to 6% had no influence on urinary Ca excretion when the diet contained .6% P. However, when the diet contained 4% Ca, lowering dietary P (from .6% to .3%) increased urinary Ca significantly. Increasing dietary Ca to 6% in the presence of low dietary P further elevated urinary Ca. Urine was acidic with all diets except with that containing 6% Ca and .3% P at 14 h after oviposition. Results indicate that low dietary P has a greater influence on elevating urinary Ca in laying hens than excess dietary Ca.

The effects of dietary phosphorus and parathyroid hormone (PTH) infusion rates on the avian phosphaturic response to PTH.

Experiments were performed to evaluate the effects of dietary available phosphorus (aP) and PTH infusion rates on avian urinary inorganic phosphate (Pi) excretion. In experiment I, female domestic fowl were fed diets containing low (0.45%) or high (0.83%) aP for 2-4 weeks prior to renal function studies. Pi excretion was significantly higher for birds fed the high-aP diet than for birds fed the low-aP diet. PTH was infused (60-240 units kg body mass-1 h-1) unilaterally into the renal portal system. Para-aminohippuric acid (PAH), included in the unilateral infusate as a marker for effective renal portal perfusion, indicated that PTH must have been delivered to the peritubular surfaces of the infused kidney. However, bilateral but not unilateral phosphaturia occurred, and there were no significant differences in the phosphaturic responses to PTH when low- and high-aP diet treatment groups were compared. In experiment II, PTH was infused at rates of 1-5 units h-1. Infusing PTH at 5 units h-1 caused a unilateral increase in urine flow but the phosphaturic response was still bilateral. It appears unlikely that unilateral renal portal PTH infusions can be used to trigger unilateral phosphaturia in domestic fowl.

[The determination of the rate of protein synthesis of the whole body of growing broilers]. / Zur Bestimmung von Proteinsyntheseraten des Gesamtkörpers wachsender Broiler.

The purpose of the investigations was to prove a method, developed for monogastric mammalians, based on a 3-compartment-model and assuming a proportional growth of the pools of total N, whether it is applicable to growing poultry. The tracer, 15N-L-lysine, was given quasi-continuously for four days. In this time and in the following period of five days without tracer intake, the 15N-excretion in the urine was measured. The average of the live weight of the broiler cockerels was 1724 g. The animals were obliged to be colostomized to sample the urine. Using the fluxes of lysine, the calculation of the whole body protein synthesis rate yields 64.1 g/d. The protein degradation rate yields 54.4 g/d. The adequate values of the fractional rates of protein synthesis and -degradation for the whole body (without feathers) were 23.3% respectively 19.8%. By this it is clearly shown, that the applied method gives real dates of the parameters of the N-metabolism for growing broilers, which are in the range of values for muscle proteins and proteins of the whole body of growing poultry, published by other authors.

Avian diuretic response to renal portal infusions of the mycotoxin citrinin.

Citrinin is a nephrotoxic mycotoxin produced by common molds. Previous research has shown that citrinin causes increased urine flow, increased free water clearance, and increased sodium, potassium, and inorganic phosphate excretion. The present study was conducted to evaluate the dose-response effects of citrinin and to further evaluate previously reported phosphaturic effects of citrinin. Ureteral urine was collected from anesthetized domestic fowl during a control period (30 min) and during unilateral renal portal infusion (90 min) of citrinin carrier vehicle, 200 ppm citrinin, or 400 ppm citrinin. Comparisons of the portal infused vs. uninfused kidneys were used to evaluate the direct effects of citrinin. Citrinin caused acute (unilateral) dose-related increases in urine flow, free water clearance, and fractional sodium excretion and dose-related decreases in urine osmolality. Citrinin had no direct effect on glomerular filtration rates, fractional potassium excretion, or fractional inorganic phosphate excretion. An additional group of birds received systemic intravenous infusions of parathyroid hormone (PTH) beginning 40 min after the start of unilateral renal portal infusion of citrinin. The citrinin and PTH infusion were continued for 60 min. Fractional inorganic phosphate excretion increased bilaterally during the citrinin-PTH infusion period but citrinin had no direct phosphaturic effect. Previously reported phosphaturic effects of citrinin were not confirmed in the present study.

[The effect of straw meal on the crude protein and amino acid metabolism and digestibility of crude nutrients in broiler hen breeds. 1. Problems, experimental review and N-excretion in the urine]. / Der Einfluss von Strohmehl auf den Rohprotein- und Aminosäurenstoffwechsel und die Verdaulichkeit der Rohnährstoffe bei Broilerzuchthennen. 1. Mitteilung. Problemstellung, Versuchsübersicht, N-Ausscheidung über den Harn.

The metabolization of the straw N and the influence of the straw on N excretion in urine were studied in 2 experiments with colostomized broiler hens and with 15N labelled wheat straw as well as 15N labelled wheat. In experiment 1 the test animals divided up into 4 groups received 0 g, 20 g, 30 g and 40 g straw meal per animal and day in addition to 120 g mixed feed. The daily 15N-excess (15N') intake from the straw was 18.4 mg, 27.5 mg and 36.7 mg. The amount of 15N' daily consumed with the labelled wheat in experiment 2 was 119.7 mg. 40 g straw meal resulted in a significantly increased amount of urine (p less than 0.05). The amounts of urine N and uric acid N were only increased as a tendency. On average the productive N decreased as a consequence of the straw meal supplement from 1070 mg/animal and day (control) to 764 mg/animal and day after 40 g straw meal supplement. The productive 15N' of the labelled wheat was not influenced by the straw meal supplement. The productive 15N' of the straw increased from 3.8 mg/animal and day (20 g straw) to 13.4 mg/animal and day (40 g straw). In contrast to 15N wheat, straw as a 15N source resulted in a lower labelling of uric acid N in comparison with urine N. It can be assumed that the changed metabolization of the straw N is influenced by microbial processes in the intestines.

Urinary hydroxyproline excretion in male and female chickens.

Hydroxyproline was measured in 24-hr urine samples at 60 and 120 days of age in male and female broiler chickens that were prepared by the "anus praeternaturalis" technique. Twenty-four-hour urine output did not differ between females and males (32.82 +/- 1.02 ml and 33.98 +/- .54 ml, average +/- SD, respectively), whereas 24-hr urinary hydroxyproline excretion was greater in females than in males after 60 days of age. Urinary hydroxyproline excretion tended to decrease with age in males and increase with age in females. Because most of the hydroxyproline is probably derived from bone collagen, the results suggest that there are differences between mineral exchange processes in female and male chickens.

Estimation of nitrogen digestibility in poultry: content and distribution of major urinary nitrogen compounds in excreta.

The investigation concerned the digestibility of nitrogen and the content of uric acid, ammonia, and urea in urine and feces in White Leghorn layers. Eight colostomized hens were given a commercial cage-layer diet. Feces and urine were collected under acid conditions. Acidified urine contained more ammonia than untreated urine. For quantitative determination of ammonia, Urine collection ought to be done under acid conditions. Of urinary nitrogen uric acid represented 88%, ammonia 7%, urea 3%, and 2% unidentified. Urinary ammonia constituted 90% of ammonia in total excreta and urinary urea 86% of the urea in excreta. By means of these distribution factors and content of nitrogen compounds in total excreta, good estimates of the nitrogen digestibility were obtained. Our method appears to be applicable to chickens of other ages, sex, breeds, and environmental conditions.