C.A. (Kees) Kan

C.A. (Kees) Kan
None

PhD
Retired.

About

143
Publications
151,653
Reads
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1,627
Citations
Additional affiliations
April 1996 - April 2007
Wageningen University and Research Center
Position
  • Senior Researcher
Description
  • Studies in poultry, pigs and cows regarding residue formation of unwanted substances, feed additives and veterinary drugs in eggs, milk, muscle and organs. Efficacy testing of veterinary drugs. Testing of GMO containing feedstuffs in broilers
April 1971 - April 1996
Spelderholt Institute for Poultry Research
Position
  • Senior Researcher
Description
  • Studies in poultry nutrition, residues and effects of feed contaminants such as organochlorine compounds, heavy metals and mycotoxins, effects and residue formation of feed additives and veterinary drugs in poultry and eggs
Education
January 2001 - April 2003
Bergische Universität Wuppertal
Field of study
  • Food Chemistry
September 1965 - March 1971
Utrecht University, Utrecht, Netherlands
Field of study
  • Biochemistry, Food Chemistry

Publications

Publications (143)
Conference Paper
Full-text available
Residues in eggs arise from accidental or intended exposure to chemicals. The exposure routes are by oral ingestion (feed, water, soil and preening), by inhalation, by dermal absorption or by injection. Chemical contaminants are not a major issue in quality control (HACCP) systems. Risk management of chemicals has not been widely addressed and if s...
Chapter
Full-text available
Generally, the lowest concentrations of any chemical residue are found in muscle tissue (of poultry). On the other hand, the excretory organs, liver and kidney, contain the highest concentrations of chemical contaminants. The exceptions are the fat soluble organohalogen contaminants which often reach the highest concentrations in fatty tissues, inc...
Article
Full-text available
ABSTRACT - The title may raise questions about definitions of the terms used. The more obvious ones are: 1) What is transfer? 2) How to define toxic; and 3) How to define feed or food. A more underlying question is how to measure the substances we are interested in. The (often) chemical methods used, are not always sensitive or specific enough. Som...
Article
Full-text available
The welfare of farm animals is strongly influenced by the man-made environment. Welfare problems also arise from reduced homeostatic capacities in animals. Feed additives, used to promote growth or to prevent diseases can alter the animals' self-regulating capacities thus affecting their welfare. The EU regulates the use of these additives within s...
Article
Full-text available
Toxic substances such as dioxins, mycotoxins, heavy metals, pesticides, veterinary drugs and polycyclic aromatic hydrocarbons are almost ubiquitous in the environment. Thus, they are also present in ingredients for animal feed. Adequate risk management depends on knowledge of absorption, metabolism, carry-over and toxicological profile of these sub...
Preprint
Full-text available
This is the abstract of chapter 17, pages 415 - 441 in: Chemical hazards in foods of animal origin Frans J.M. Smulders, Ivonne M.C.M. Rietjens, Martin Rose (eds) Food safety assurance and veterinary public health no. 7 DOI 10.3920/978-90-8686-877-3_17 ©Wageningen Academic Publishers 2019
Article
Full-text available
Growing male pigs were exposed to cadmium (Cd) at levels around 1 and 10 mg kg(-1) feed for up to 12 weeks, administered as CdCl2 or Cd-cysteine (CdCys). Pigs exposed to 10 mg kg(-1) showed decreased growth during the last 3 weeks. Liver and kidney concentrations of Cd continuously increased over the entire 12-week exposure, exceeding the European...
Article
Full-text available
At the end of 2004, during a routine monitoring project, high levels of PCDDs in milk from two farms were found. Using a bioassay and the congener patterns obtained by HRGC/HRMS, the source was traced back to the use of kaolinic clay for sorting potatoes in a production process of French fries. Rest products, especially peelings after scrubbing, we...
Article
Full-text available
At the end of 2004, during a routine monitoring project, high levels of PCDDs in milk from two farms were found. Using a bioassay and the congener patterns obtained by HRGC/HRMS, the source was traced back to the use of kaolinic clay for sorting potatoes in a production process of French fries. Rest products, especially peelings after scrubbing, we...
Article
Full-text available
Soil intake may be the most prominent source of environmental contaminants for free range and organic hens, but there are no quantitative data concerning soil intake by domestic hens. Consumption of soil of 14-32 g a day can be estimated from literature, but such a dilution of nutrient intake seems incompatible with high productivity. In this study...
Technical Report
Full-text available
De dierlijke produtieketen bestaat uit diverse schakels, waarbij een grote reeks plantaardige producten de basis voor de dierlijke producten vormen. Er zijn een aantal typen basisgegevens noodzakelijk om de relatie te kunnen onderzoeken tussen de kwaliteit van de plantaardige voedermiddelen en de kwaliteit van de dierlijke producten,. Deze gegevens...
Technical Report
Full-text available
Het is belangrijk om onderzoek uit te voeren ter onderbouwing van de handhaving van normen in diervoeders en diervoedergrondstoffen, omdat een substantieel deel van het voedsel van dierlijke oorsprong is. In dit kader beoogt het project Normvergelijking modellen inclusief de bijbehorende data aan te leveren voor een onderbouwing van de normstelling...
Article
Full-text available
Chlorinated pesticides and halogenated environmental contaminants can enter the animals in a variety of ways. The most important way is via the feed (including soil intake). However, direct application on the animal and contact with the skin as well as inhalation via the airways should not be ruled out. Most components of animal feed are digested...
Article
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Technical Report
Full-text available
De opname van cadmium door runderen en ander grazend vee in de Kempen leidt mogelijk tot overschrijding van warenwetnormen in orgaanvlees en gezondheidschade. Om na te gaan hoe groot het gebied is waar de inname via grond, voer en water kan leiden tot normoverschrijding is een model opgesteld voor runderen en schapen. Dit model berekent voor de hel...
Article
Achtereenvolgens zal worden ingegaan op de definities van claims, begrippen in diervoeding, de regelgeving en implementatie van diervoeding en humane voeding. Tevens wordt het gebruik van claims in de praktijk inclusief het scoren van de gevonden claims beschreven evenals de schriftelijke enquête die gehouden is bij een aantal petfoodbedrijven. Tot...
Article
Full-text available
Organic pollutants in feed, food and environment may be due to both “natural” processes as well as industrial activities. The formation of acrylamide during potato frying as well as polycyclic aromatic hydrocarbons during a barbecue are examples of the first category. Mineral hydrocarbons and chlorinated paraffin’s are spread in the environment and...
Article
Full-text available
Laying hens were fed with feed from the Belgian dioxin incident diluted ten-fold with non-contaminated feed, resulting in concentrations of 61 ngTEQkg(-1) PCDD/Fs, 23 ngTEQkg(-1) non-ortho PCBs, 116 ngTEQkg(-1) mono-ortho PCBs and 3.2 mgkg(-1) of the seven indicator PCBs. Following exposure for seven days, feed was replaced by non-contaminated feed...
Article
Full-text available
A mathematical model for the kinetics of carry-over of dioxins and dioxin-like PCBs from feed mixed with contaminated oil to eggs has been developed. This model incorporates uptake of the compounds over the gut wall and their subsequent transport by blood, distribution over the body, hepatic metabolism and excretion through egg yolk fat. The model...
Article
Full-text available
Laying hens were fed with compound feed containing six different levels of dioxins, dioxin-like PCBs and indicator PCBs for a period of 56 days. This was followed by a period of 56 days on clean feed. Dioxin levels in feed varied from background levels to three times the current EU tolerance limit of 0.75 ng TEQ/kg. At all dose levels a rapid incre...
Article
Full-text available
Het doel van dit rapport is het geven van een overzicht in het effect van mycotoxinen in varkens, de risico's van het verstrekken van ruwvoer en stro, inzicht in mogelijke factoren die dieren gevoeliger (lijken te) maken voor de effecten van mycotoxinen en methodieken voor het vaststellen van mycotoxicose
Technical Report
Full-text available
Uit onderzoek van de AID blijkt nicotine gebruikt te worden voor de bestrijding van bloedluis bij kippen. Dit levert mogelijk gezondheidsrisico's op voor de consument van het kippenvlees of de eieren. Omdat niet duidelijk is of het nicotine na de bestrijding van bloedluis in het vlees of eieren achterblijft is, in opdracht van LNV/VD, een verkennen...
Conference Paper
Full-text available
Residues in poultry arise from accidental or intended exposure to chemicals. The exposure routes are by oral ingestion (feed, water, soil and preening), by inhalation, by dermal absorption or by injection. Chemical contaminants are not a major issue in the principles of organic or free-range systems. Risk management of chemicals has not been addres...
Article
Full-text available
We evaluated the nutritional value of broiler diets containing approximately 35% soybean meal from insect-protected soybean containing CrylAc protein, or from a similar nontransgenic control, or from 7 reference commercial soybean varieties. The feeding trial lasted 41 d, and each treatment consisted of 10 replicates of 1-d-old Ross 508 broilers (5...
Article
Full-text available
To investigate the kinetics of PCBs and dioxins, 3 week old broilers and 3 month old pigs were fed with a 10-fold diluted feed from the Belgium crisis for one week, followed by a period on clean feed. In the case of broilers this resulted in levels for dioxins, non-ortho and mono-ortho PCBs in fat of 102, 84 and 216 ng TEQ/kg, summarized to 402 ng...
Article
Full-text available
We evaluated the nutritional value of broiler diets containing approximately 40% wheat grain from Roundup Ready wheat (MON 71800), its similar nontransgenic control (MON 71900), or reference commercial wheat varieties. The feeding trial lasted 40 d, and each treatment consisted of 10 replicates of 1-d-old Ross 308 broilers (5 pens of males and 5 pe...
Article
Full-text available
Om het verband te bestuderen tussen dioxine- en PCB-gehaltes in voer van kippen en hun eieren, werden 6 groepen legkippen gedurende 56 dagen gevoerd met voeders met verschillende gehaltes aan dioxines, dioxine-achtige PCBs en indicator PCBs. Vervolgens kregen de kippen gedurende 56 dagen schoon voer.Op basis van de data en fysiologische gegevens ov...
Article
Uit berekeningen blijkt dat er voor koeien in de stalperiode soms een tekort dreigt aan vitamine D en E. Voor vitamine A geldt dat alleen in rantsoenen met uitsluitende hooi. Gehalten van vitamine A in voordroogkuilen van gras/klaver op Bioveembedrijven komen redelijk overeen met literatuurgegevens. Die van vitamine E waren de helft van wat verwach...
Technical Report
Full-text available
De problemen met dioxinen en dibenzofuranen in koeien en schapen in de omgeving van de Afvalverwerking Rijnmond (Lickebaert gebied 1985-1990) en de contaminatie van citruspulp (1998-1999) hebben aanleiding gegeven tot een aantal proeven. In deze notitie worden de belangrijkste gegevens van deze proeven samengevat. Doel van dit overzicht is om de hu...
Article
Behoeftenormen voor vitamine A kunnen in de stalperiode, in rantsoenen met hoofdzakelijk voordroogkuil, geheel gedekt worden uit ruwvoer. Voor vitamine D en E is aanvulling van het ruwvoerrantsoen nodig voor dekking bvan de behoefte,. Voor rantsoen berekening zijn betrouwbare en goedkope analysemethoden voor vitaminen gewenst. Onderzoek naar altern...
Article
Full-text available
The reduction in levels of organochlorine pesticide residues in food of animal origin in the past 30 years has been achieved especially by controlling entrance via the feed chain. A further reduction was achieved by registration and use of less persistent pesticides both for direct treatment of animals and of plant material. The remaining problems...
Conference Paper
Full-text available
The nutritional value of soybean meal derived from two insect protected soybean lines, 726 and 781 containing Cry1Ac protein was compared to that of the parental control line and seven commercial varieties in a broiler growth trial over 41 days. Neither growth, feed conversion, carcass or cutup yields or gross chemical composition of breastmeat of...
Article
Full-text available
Veterinary drugs and feed additives (especially some coccidiostats) can be absorbed by the digestive tract of laying hens and transferred to the egg. Physicochemical characteristics of these compounds determine their pharmacokinetic behavior and distribution to and within the egg. Traditionally the quite lipid soluble drugs and additives are expect...
Conference Paper
Full-text available
A sensitive and selective method was developed for the analysis of dexamethasone, flumethasone and triamcinolone acetonide in biological matrices. The method is based on solid phase extraction for extract purification and concentration and LC-MSn for separation and identification. The method can be used for the screening and quantification of dexam...
Conference Paper
Full-text available
Los gobiernos y la industria de todo el mundo se han puesto de acuerdo en la necesidad de una producción higiénica de los productos de origen animal, especialmente los avícolas,los huevos y sus derivados. Las razones que les han llevado a este punto son las reacciones fuertemente negativas de los consumidores y las asociaciones de consumidores ante...
Article
Full-text available
Flubendazole residues in eggs were experimentally induced by providing groups of 8 laying hens feed with approximately 3, 10 and 30 mg kg-1 flubendazole for 21 days. Eggs were sampled during this period and one week after the administration. Samples of both whole egg and egg white/yolk were analysed separately. Flubendazole analysis was performed b...
Article
Full-text available
The exposure of lactating cows to a dioxin contaminated feed ingredient (CPP) leads to a rapid accumulation of dioxins in milk. Already after 2 to 3 weeks of exposure the dioxin levels in milk exceed the Dutch tolerance level (6 pg i-TEQ/g). On the other hand, the excretion of dioxins, after a relatively short period of exposure, is also rapid and...
Article
Full-text available
When laying hens are given veterinary drugs, residues will almost inevitably appear in the eggs. The compartmental separation of residues between yolk and white appears to depend on the structure and lipid solubility of the drug, the dose and extent of exposure
Article
Full-text available
Antibodies against penicillins were induced in eggs of laying hens after immunization with 6-aminopenicillanic acid (6-APA) coupled to key-hole limpet hemocyanin (KLH). Development of the antibody titer was monitored by an indirect enzyme-linked immunosorbent assay (ELISA), with 6-APA coupled to ovalbumin as antigen for coating microtiter plates. D...
Conference Paper
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Article
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Technical Report
Full-text available
Lage gehaltes van veevoedertoevoegings-of diergeneesmiddelen in pluimveevoeder kunnen residuen in vlees of eieren veroorzaken. Systematisch onderzoek naar deze (kwantitatieve) relaties is in Nederland rond 1986 aangevangen en heeft veel nuttige informatie voortgebracht. Dit rapport, dat is opgesteld op verzoek van het PWr, bevat gegevens van alle r...
Conference Paper
Full-text available
Eleven different sulfonamides with pKa values ranging from 4.7 to 1 1.3 were tested for their partition coefficient between dichloromethane and phosphate buffer at pH values 6.0 and 7.6 (representing the pH values of yolk and egg white resp.). The same compounds were included in the diet of laying hens and levels in yolk and egg white were determin...