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At least 19 recordsLinked to original sources
PubMed2001

The "egg-egg" syndrome: occupational respiratory allergy to airborne egg proteins with consecutive ingestive egg allergy in the bakery and confectionery industry.

Allergies to various inhalative allergens are a serious problem in the bakery and confectionery industry. Sensitization to wheat flour and enzymes such as alpha-amylase are a frequent cause of occupational asthma. Airborne egg allergens have been reported as another cause of respiratory allergy. We examined bakery and confectionery workers with respiratory symptoms due to egg aerosols. Skin tests (SPT), scratch tests (ST), nasal provocation tests (NPT) and serological examinations (IgE) were performed. Lung function was assessed by spirometry, and continuous registration of aerosols and particulates as well as gravimetric sampling was done at the workplace. Four bakery and two confectionery workers intensively exposed to airborne egg proteins suffered from conjunctivitis and rhinitis, four also from asthma. Subsequently, three of these four workers reported symptoms after ingestion of food that contained egg. SPT with commercial egg white and egg yolk extracts were negative in four cases. Only two employees had clearly positive SPT to commercial egg allergens and reacted also to wheat flour extracts. Scratch tests with native egg proteins were positive in four employees. Specific IgE to egg white and egg yolk were positive (CAP > or = 2) in three and in four cases, respectively, whereas they were negative in two cases. Elevated levels of specific IgE to lysozyme were detected in four employees. Two workers were sensitized to lysozyme but not to other egg proteins. The clinical relevance of egg sensitization was confirmed by continuous air sampling and by correlating the onset of the respiratory symptoms which were reflected by a significant decline (> or = 30%) of the forced one second capacity (FEV1) in two workers. Sieving of egg white powder and an inadequate spray station for liquid eggs were identified as sources of excessive allergen exposure. Bakery and confectionery workers exposed to airborne egg proteins are at risk of developing occupational asthma and subsequent nutritive egg allergy. To our knowledge, these are the first cases of inhalative egg allergy and subsequent nutritive egg allergy reported in the literature, which we refer to as the "egg-egg syndrome" in analogy to the already known "bird-egg" and "egg-bird" syndromes.

Adult↗
PubMed1983

A clinical and immunological study of allergy to hen's egg white. VI. Occurrence of proteins cross-reacting with allergens in hen's egg white as studied in egg white from turkey, duck, goose, seagull, and in hen egg yolk, and hen and chicken sera and flesh.

The occurrence of proteins cross-reacting with allergens in hen's egg white was studied in turkey, duck, goose and seagull egg whites, in hen egg yolk, and in hen and chicken sera and flesh. The study was based upon quantitative immunoelectrophoretic techniques. The different egg whites were all found to contain proteins cross-reacting with most of the allergens in hen's egg white, but the degree of cross-reactivity varied considerably among the various egg whites. All egg whites contained proteins able to bind human IgE-antibody in the sera of patients with allergy to hen's egg white. Several proteins cross-reacting with allergens in hen's egg white were also detected in egg yolk and in hen and chicken sera and flesh. Clinical implications of the results are discussed.

Allergens↗
PubMed1985

Effects of early maturation of brown egg-type pullets, flock uniformity, layer protein level, and cage design on egg production, egg size, and egg quality.

Eight-week-old Harco Sex-Link pullets were assigned to four growing regimens. Feed was restricted to Group 1. The birds reached an average weight of 1.52 kg at 20 weeks of age and were then light stimulated. Group 2 received the same ration ad lib and reached an average weight of 1.64 kg at 16 weeks. At this age they were light stimulated. Birds in Groups 3 and 4 were separated into two weight classes at 8 weeks of age. Those below the median weight received an 18% protein grower ration and those above the median weight a 16% ration. Group 3 birds were grown similarly to Group 1; Group 4 birds were grown similarly to Group 2. At housing, each group was equally divided and given either a 17 or 19% protein layer ration. Two cage designs (standard and reverse) were used and each treatment combination was equally represented. Ad lib-fed, early-housed pullets reached 1.64 kg at 16 weeks of age, but they did not come into production until 19.4 weeks of age. Hen-day percent production (HDP) was significantly less than for the late-housed pullets. Feed per dozen eggs was not affected by the early housing, but early-housed pullets laid significantly smaller eggs and feed per gram egg was significantly increased. Hens in reverse cages on a 19% protein layer ration laid the largest eggs in weight and size. Although early housing had a detrimental effect on average egg weight, it appeared possible to manipulate egg weight and size distribution through a combination of cage design and layer protein. Birds grouped by body weight at 8 weeks had higher uniformity, but this trait was not correlated with egg numbers or size. Moreover, housing body weights were not significantly correlated with egg size, suggesting factors other than body weight were responsible for the smaller eggs from early-housed pullets.

Animals↗
PubMed1998

[Appearance of ovomucoid in coagulated egg yolk passing through from soluble fraction of coagulated egg white in boiled egg].

Ovomucoid is a egg white protein which has a strong allergenicity with a unique characteristic in heat-noncoagulable one contrast to heat-coagulable other major egg white proteins. By ELISA and immunoblots analysis, ovomucoid was detected in heat-coagulated egg yolk after immediate boiling of hen's egg for 15 min (boiled egg) at the concentration of 4.8 +/- 0.8 micrograms/g egg yolk, but not detected in raw egg yolk collected by insertion of a needle into the egg yolk cavity. Ovomucoid in heat-coagulated egg yolk was increased by standing the boiled eggs at room temperature for 10, 30, 60 and 120 min at the concentration of 7.5 +/- 3.4, 17.2 +/- 15.1, 28.1 +/- 5.9 and 78.8 +/- 31.3 micrograms/g egg yolk, respectively. The soluble fraction prepared from heat-coagulated egg white of boiled egg contained 37.7 +/- 3.2 mg/ml of proteins including 14.2 +/- 11.9 mg/ml of ovomucoid as a major and miners of detectable ovalbumin and ovotransfferin. These results suggested that the appearance of ovomucoid in coagulated egg yolk of boiled egg was due to passing the soluble fraction rich in ovomucoid in heat-coagulated egg white through into the coagulated egg yolk, which may have notable consequences for the present of ovomucoid as a major egg white allergen in yolk egg of boiled egg.

Allergens↗
PubMed1997

Egg sharing and egg donation: attitudes of British egg donors and recipients.

The question of payment to egg donors has recently focused the attention of both the Human Fertilisation and Embryology Authority (HFEA) and licensed clinics. An acute shortage of egg donors and the rising costs of assisted conception treatment are matters of grave concern to many patients. To understand the emotional and social effects of egg sharing and egg donation, we conducted a survey of attitudes in a group of women who had some knowledge or experience of egg donation. A total of 750 questionnaires were sent out of which 217 were returned within the specified time limit. From these, 107 respondents had experience of egg donation and 110 had made enquiries about donation. The data from these questionnaires were collated and tabulated by the National Opinion Polls (NOP) Research Group. An analysis of the data produced the following key findings: (i) donating or sharing eggs is a social issue, 94% discuss it with partners/family/friends; (ii) altruistic motives are not the prerogative of non-patient volunteers-egg share donors felt that helping the childless was as important as having a chance of in-vitro fertilization (IVF) for themselves; (iii) the treatment procedure causes the most anxiety for egg donors. The recipients were most concerned about delays, donor characteristics and how the eggs were allocated; (iv) most respondents (65%) with prior experience of egg sharing would do it again - 63% of egg share donors, 72% of egg share recipients; (v) cash rewards to egg donors and outright advertising for donors were rejected by 64 and 62% of the sample respectively; and (vi) counselling was highly valued and there were no instances of 'shattered lives' after treatment. The findings do not support the recently announced intentions of the HFEA to disallow payment to gamete donors on the grounds of devalued consent. There is no precedent in modern medicine for egg sharing. The patients surveyed drew a clear distinction between egg sharing and financial rewards. As long as egg donation is not covered by the National Health Service, it is fairer to offer egg sharing than to refuse treatment to those unable to pay.

Adult↗
PubMed2000

Egg maturation, egg resorption and the costliness of transient egg limitation in insects.

Although there is widespread agreement that the cost of oviposition underlies selective oviposition in insects, there is no consensus regarding which factors mediate the cost of oviposition. Models have suggested that egg costs are often paramount in those insects that do not continue to mature eggs during the adult stage (pro-ovigenic insects). Here we address the hypothesis that egg costs are generally less significant in synovigenic insects, which can replenish oocyte supplies through continuous egg maturation. A dynamic optimization model based on the biology of a highly synovigenic parasitoid, Aphytis aonidiae, suggests that the maximum rate of egg maturation is insufficient to balance the depletion of eggs when opportunities to oviposit are abundant. Transient egg limitation therefore occurs, which imposes opportunity costs on reproducing females. Thus, whereas the most fundamental constraint acting on the lifetime reproductive success of pro-ovigenic species is the fixed total number of eggs that they carry at eclosion, the most fundamental constraint acting on a synovigenic species is the maximum rate of oocyte maturation. Furthermore, the ability of synovigenic species to reverse the flow of nutrients from the soma to oocytes (i.e. egg resorption) has a dramatic influence on the cost of oviposition. Whereas females in hostrich environments may experience oviposition-mediated egg limitation, females in host-poor environments may experience oosorption-mediated egg limitation. Both forms of egg limitation are costly. Contrary to initial expectations, the flexibility of resource allocation that typifies synovigenic reproduction actually appears to broaden the range of conditions under which costly egg limitation occurs. Egg costs appear to be fundamental in mediating the trade-off between current and future reproduction, and therefore are an important factor favouring selective insect oviposition.

Animals↗
PubMedDate not supplied

[Dynamics of amino acid and protein metabolism of laying hens after the administration of 15N-labeled wheat protein. 3. Incorporation of 15N into egg shell, egg white and egg yolk].

12 colostomized laying hybrids received a ration meeting their requirement of 15N labelled wheat with a 15N excess (15N') of 14.37 atom-% over 4 days. The 15N' of the total ration amounted to 4.47 atom-%. Each hen consumed 135 mg 15N' per day. On another 4 days the same rations with non labelled wheat were fed. The 12 hens laid 56 eggs during the 8 days of the experiment. They were divided into egg shell, white and yolk of egg. In addition, the protein of the white and yolk of egg was precipitated with trichloric acetic acid (TCA) and the nitrogen in these fractions was determined. On average of the 56 eggs, the N quota in the egg shell was 5.3%, in the white of egg 49.1% and in the yolk 45.6%. The atom-% 15N' in the shells of the eggs laid on the first day of the experiment was on average 0.21, whereas only 0.03 and 0.02 atom-% 15N' resp. could be detected in the white and yolks of the eggs. On the first day after the last 15N application the atom-% 15N' in the egg shell and the white of egg was highest and amounted to 2.33 and 2.43 atom-% resp. The highest value of 1.83 atom-% 15N' in the yolk was ascertained 3 days after the last 15N intake. The mean quota of TCA-precipitable N in the white of egg is 97.6% and in the yolk 94.4% of the respective total N. The atom-% 15N' in the non-protein N-compounds was higher than in the protein fractions.

Amino Acids↗
PubMed1999

The effect of dietary wheat middlings and enzyme supplementation. 1. Late egg production efficiency, egg yields, and egg composition in two strains of Leghorn hens.

A study was conducted to test the effects of wheat middlings (WM) with and without enzyme (xylanase and protease) supplementation on late egg production (EP), egg yields, and egg composition in two strains of Leghorn hens (DeKalb Delta and Hisex White). Six diets were randomly assigned to 300 birds (150 birds per strain) from 42 to 60 wk of age. Diet 1 was a corn-soybean meal control, Diets 2 and 3 had 8 and 16% WM, respectively, Diet 4 had 8% WM with 0.1% enzyme, and Diets 5 and 6 had 16% WM with 0.1 and 0.2% enzyme, respectively. Each dietary treatment was replicated five times per strain. Egg production, feed consumption (FC), feed efficiency (FE), percentage dirty eggs, specific gravity (SP), egg weight (EW), and egg mass (EM) were measured on a weekly basis. Egg components (EC) were measured biweekly and birds were weighed every 4 wk. Egg production was not significantly affected by diet, with averages of 83.7, 85.7, 84.1, 84.2, 82.3, and 84.0% for Diets, 1, 2, 3, 4, 5, and 6, respectively. Strain had a marked effect on FC, with Hisex having higher FC than DeKalb hens. Feed consumption also showed a significant diet by strain effect, being lower for Hisex hens fed diets with enzyme compared to diets without enzyme. DeKalb hens had better FE than Hisex hens, and addition of enzyme to 16% WM improved it further. Strain and diet had a significant effect on EC with higher percentages of albumen and yolk for diets with enzyme and for DeKalb hens. Percentage shell was lower for DeKalb hens than for Hisex hens but was not affected by diet. There was also a significant increase in EW for Diets 4 (63.1 g), 5 (63.8 g), and 6 (63.2 g) compared to Diets 1 (62.1 g), 2 (62.4 g), and 3 (63.0 g), with DeKalb hens showing an increase with Diet 5 compared to Hisex hens. Egg mass improved with the higher rate of enzyme in 16% WM diet compared to the lower enzyme level. Specific gravity declined with enzyme supplementation in WM diets. Eggs from DeKalb hens had lower SP than those from Hisex hens for all diets. Percentage dirty eggs did not differ significantly among treatments but was higher for the Hisex strain than for the DeKalb strain. There were no differences in BW between the two strains of hens or among diets. Adding protease and xylanase to diets rich in fiber can improve the egg output without affecting production parameters.

Animal Husbandry↗
PubMed1995

Influence of selection for increased egg production, body weight, and shank width of turkeys on egg composition and the relationship of the egg traits to hatchability.

Egg traits, mature BW, fertility, and hatch of fertile eggs were measured in lines of turkeys selected for increased egg production, increased 16-wk BW, and increased shank width and in corresponding randombred controls to determine the effects of selection. Genetic increases in egg production were associated with decreased mature BW and egg weight with no change in fertility or hatchability. The decrease in egg weight was associated with a proportional decrease in the albumen, shell, and yolk. Genetic increases in BW were associated with increased mature BW and egg weight and decreased fertility and hatch of fertile eggs. The increase in egg weight was primarily due to an increase in albumen. Selection for increased shank width had little influence on egg traits. Fertility and hatch of fertile eggs were correlated. Hatch of fertile eggs was positively correlated (after the effects of line were removed) with absolute and percentage shell and percentage yolk and negatively correlated with percentage albumen. The regression coefficients of egg weight on mature BW differed between lines, with the relationship being larger in smaller lines.

Animals↗
PubMedDate not supplied

The effects of 6/85 live Mycoplasma gallisepticum vaccine in commercial layer hens over a 43-week laying cycle on egg production, selected egg quality parameters, and egg size distribution when challenged before beginning of lay.

In each of two trials, 80 commercial leghorn-type pullets were separated into two treatments with four replicates of 10 chickens in each treatment. Forty pullets were designated as controls and received no inoculation, whereas the remaining 40 pullets received the 6/85 vaccine strain of Mycoplasma gallisepticum (MG) at 10 wk of age. Hen-day egg production, egg weight, eggshell strength, Haugh unit score, pimpling incidence, and blood/meat spot incidence were monitored and recorded weekly in each trial through an entire laying cycle of 43 wk. Further, eggs from all treatments were collected daily, Monday-Thursday, and individually weighed. No significant difference was observed between the treatments for 43-wk means for hen-day egg production, for any of the monitored egg or eggshell quality parameters, or for the number of extra large, large, medium, small, pee wee, or undergrade egg sizes. A significant (P < or = 0.05) difference was observed for the number of jumbo-sized eggs between the two treatments. Results of this study suggest that vaccination of commercial layer chickens at 10 wk of age with 6/85 strain MG does not detrimentally impact egg production, egg size distribution, or ovary/oviduct function as evidenced by selected egg parameters monitored in this study.

Animals↗
PubMed2002

Vitamin E supplementation can alleviate negative effects of heat stress on egg production, egg quality, digestibility of nutrients and egg yolk mineral concentrations of Japanese quails.

The aim of this study was to determine if the negative effects of high ambient temperature (34 degrees C) on egg production, egg quality, digestibility of nutrients, and mineral content of egg yolk could be alleviated by dietary vitamin E (dl-alpha-tocopheryl acetate) supplementation in laying Japanese quails (Coturnix coturnix japanica). Japanese quails (n=240; 7-week-old) were divided into eight groups, 30 birds per group. The quails were fed either a basal diet or the basal diet supplemented with either 125, 250 or 500 mg of dl-alpha-tocopheryl acetate/kg of diet. Birds were kept at 22 degrees C and 55% relative humidity (RH). At 14 weeks of age, the thermo-neutral (TN) group remained in the same temperature as at the beginning of the experiment, whereas the heat stress (HS) group was kept at an environment-controlled room at 34 degrees C and 44% RH for 3 weeks. Heat exposure decreased performance when basal diet was fed (P=0.001). With 250 and 500 mg/kg of diet, an increase in body weight (P=0.01), feed intake (P=0.01), egg production (P=0.001), and improvement in feed efficiency (P=0.01) was found with vitamin E supplementation in quails reared under heat stress conditions (HS). Similarly, egg weight (P=0.01), egg specific gravity (P=0.01), egg shell thickness (P=0.05) and Haugh unit (P=0.01) were positively influenced by vitamin E supplementation. Heat exposure decreased digestibility of dry matter (DM) (P=0.03), organic matter (OM) (P=0.05), crude protein (CP) (P=0.02), ether extract (EE) (P=0.05) and were elevated by supplemental vitamin E (P<or=0.02). Egg yolk concentrations of Zn, Fe, and Mn decreased under high environmental temperature and were increased to values of the control group (P=0.001) when dietary vitamin E was supplemented. No significant differences in any values were observed in TN groups. Results of the present study conclude that supplementation with 250mg alpha-tocopherol acetate/kg of diet can be considered to be protective management practice in a quail diet, reducing the negative effects of heat stress.

Animal Feed↗
PubMed1983

Gas-liquid chromatographic determination of trace amounts of nitrite in egg, egg white, and egg yolk.

A simple, sensitive, and practical method is described for determination of nitrite in egg, egg white, and egg yolk. Egg is deproteinized by adding a mixture of ammonium thiocyanate, mercuric chloride, and zinc acetate, and centrifuged. Nitrite in the supernate is converted to tetrazolophthalazine by reaction with hydralazine in acidic solution and then determined by gas-liquid chromatography with an electron-capture detector (GLC-ECD) and a column of OV-225 on Chromosorb W(HP). Nitrite concentrations from 5 to 50 ng/mL are calculated from peak height; the detection limit is 3 ng/mL extract. Recoveries from eggs, egg whites, and egg yolks ranged from 91.7 to 98.0%. The mean nitrite concentration in 50 egg samples was 0.04 ppm (0.01-0.11 ppm) with a detection limit of 4 ng nitrite/g.

Animals↗
PubMed1996

On hen egg fractionation: applications of liquid chromatography to the isolation and the purification of hen egg white and egg yolk proteins.

Liquid chromatography has been used as a means of egg protein analysis or as a method for the purification of egg proteins. Several chromatographic methods, including gel permeation, ion-exchange, reversed-phase, hydrophobic interaction, and immobilized-ligand-affinity chromatography, have been carried out for the separation or the purification of egg yolk or egg white proteins. Ion-exchange chromatography appears to be the most frequently used method for protein isolation and it is the easiest to adapt to a process scale. From an analytical point of view reversed-phase chromatography is, at the moment, the recommended method for egg white analysis. Egg white has been fractionated more often by liquid chromatography than has egg yolk. Several chromatographic methods have been developed on a laboratory scale, but the application of these techniques on an industrial scale remains limited.

Animals↗
PubMed1989

Effect of hatching egg sanitizers on embryonic survival and hatchability of turkey eggs from different lines and on egg shell bacterial populations.

Three experiments were conducted to examine the effect of hatching egg sanitizers on embryonic survival, hatchability, and microbiological populations of turkey eggs. Each experiment consisted of two trials. Experiments 1 and 2 were designed to examine embryonic survival and hatchability following sanitization. Experiment 3 examined postsanitization levels of bacteria on the shell surface and inside the egg at Day 7 of incubation. In Experiment 1, formaldehyde fumigation (FF) was compared to quaternary ammonium (QA). In Trial 1, eggs of 359 hens representing 10 lines were randomly assigned to one of the two treatments. In Trial 2, 3,890 eggs produced from a cross of randombred control line (RBC2) females with commercial sire line (C) males were randomly assigned to one of the two treatments. Differences due to sanitizing treatment were nonsignificant in both trials. Line was significant for 7-day embryonic survival and hatch of surviving embryos in Trial 1. In Experiment 2, QA was compared with QA plus U.S.P. Formalin (QAF). In Trial 1, eggs of 288 hens representing 10 lines were randomly assigned to one of the two treatments. In Trial 2, 1,058 eggs produced from the cross of RBC2 females with C males were randomly assigned to one of the two treatments. Differences due to sanitizing treatment were significant only for 7-day embryonic survival in Trial 2; embryonic survival was highest for QA. Line differences in Trial 1 were significant (P less than .01) for 7-day embryonic survival and hatch of surviving embryos.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Embryonation and infectivity of Ascaris suum eggs. A comparison of eggs collected from worm uteri with eggs isolated from pig faeces.

Ascaris suum eggs were collected from pig faeces or dissected from worms obtained from the same pigs. Eggs from the two sources were allowed to embryonate in 0.1 N H2SO4, in 1% buffered formalin or in tap water. The embryonation of the sulphuric acid and water cultures occurred at the same speed, while the formalin cultures developed slightly more slowly. By experimental inoculation of helminth-free pigs and subsequent counting of white spots in the livers and larvae in the lungs day 7 p.i., the infectivity of eggs dissected from worm uteri and embryonated in sulphuric acid (a normal laboratory procedure) was compared with that of eggs collected from faeces and embryonated in water (i.e. more naturally developed eggs). The results suggest that the two types of eggs were equally infective. For this reason the common practice of using Ascaris eggs dissected from worms for experimental infections might be acceptable.

Animals↗
PubMed1982

Daily egg production of Ascaris lumbricoides: the distribution of eggs in the faeces and the variability of egg counts.

Fifteen children aged from 6 to 12 years who were infected with Ascaris lumbricoides were selected for the study. The number of eggs/g (e.p.g.) of stool was determined using Beaver's direct smear technique, Stoll's dilution egg count technique and Katz's modified thick smear technique. Beaver's direct smear method consistently gave a higher e.p.g. than the other two methods. Results of this study show that Katz's modified thick smear technique was the best of the three methods used. The e.p.g. depends on several factors: the amount of stool passed daily, the concentration of eggs within a stool sample, the daily egg output, the worm load, the age of the worm and the technique used for determining the egg load. The daily average egg output/female A. lumbricoides was estimated to be 238 722 (range 134 462-358 750) with an average e.p.g. of 3540. The estimation of worm load based on egg count is useful in determining the intensity of infection in an individual. The male/female worm ratio was estimated to be 1:1.4.

Animals↗
PubMed1983

A clinical and immunological study of allergy to hen's egg white. IV. Specific IGE-antibodies to individual allergens in hen's egg white related to clinical and immunological parameters in egg-allergic patients.

Different subgroups of egg-allergic patients were established according to differences in allergic symptoms provoked by hen's egg white, total IgE-level, RAST (radioallergosorbent test) results to egg white, and age. In each group the pattern of specific IgE-antibodies to individual allergens in the egg white, determined by means of crossed radioimmunoelectrophoresis (CRIE), was compared with the pattern in a control group. The RAST value to egg white was found to exert the strongest influence on the CRIE results. A few statistically significant differences in CRIE results to certain allergens were also observed in other pairs of subgroups of egg-allergic patients. Possible explanations for this are discussed. It was concluded that CRIE studies of allergens in mixed protein solutions, using a series of sera from allergic patients, will most probably give the same results and the same classification of the allergens independent of the characteristics of the patients from which the sera were collected. However, it should be emphasized that the CRIE series must include a sufficient number of patients with high RAST values to the allergen in question. Otherwise some allergens may be missed and the classification of the allergens may be different.

Adolescent↗
PubMed2000

Automated residue analysis of tetracyclines and their metabolites in whole egg, egg white, egg yolk and hen's plasma utilizing a modified ASTED system.

An automated analytical method is described allowing simultaneous determination of all tetracyclines and metabolites in whole egg, egg yolk, egg white and blood plasma of the hens. Sample pretreatment is restricted to homogenization and a dilution step. Clean-up is by on-line dialysis and on-line solid-phase extraction utilizing an extended ASTED system, followed by liquid chromatography with UV or fluorescence detection with post-column pH adjustment and confirmational analysis by LC-MS-MS. After feeding oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC) to laying hens, not only residual parent compounds could be found in the eggs but also in vivo formed 4-epimers, isochlortetracycline (ICTC) and tentatively identified N-desmethyl metabolites of OTC, TC and ICTC.

Animals↗