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Biel W, Natonek-Wiśniewska M, Kępińska-Pacelik J, Kazimierska K, Czerniawska-Piątkowska E, Krzyścin P. Detection of chicken DNA in commercial dog foods. BMC Vet Res 2022; 18:92. [PMID: 35264164 PMCID: PMC8905904 DOI: 10.1186/s12917-022-03200-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 03/04/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND These days the number of potential food allergens is very large, but chicken is one of the most common allergens in dogs. Elimination diet is one of the clinical tools for the diagnosis of allergies and allergy tests are not very reliable. The restriction diet is most commonly carried out by feeding pet foods, relying on the ingredients on the label to select an elimination diet not containing previously eaten foods. Unfortunately, mislabeling of pet food is quite common. The purpose of this study was to determine the absence or presence of chicken DNA using both qualitative and quantitative polymerase chain reaction (PCR) analysis methods in dry and wet maintenance complete pet foods for adult dogs. Results were used to verify the declared composition on the labels. RESULTS Eleven out of fifteen (73%) dog foods were produced as declared by the manufacturer, two of which showed the presence of chicken protein as stated on the label. The remaining nine foods contained amounts of chicken DNA below 1%, consistent with declarations that no chicken was added in the composition. Four of tested dog foods (27%) were not produced consistently with the declaration on the packaging. Two dog foods (one dry and one wet) did not contain the claimed chicken protein. In two foods the addition of chicken DNA was detected at the level of over 2% and almost 6%, respectively. CONCLUSIONS In this study, we focused on one of the most commonly undeclared animal species on the label-chicken protein-and performed DNA analyzes to investigate possible contamination and mislabeling. The results showed some inaccuracies. However, most of them are trace amounts below 1%, which proves compliance with the label. Our results showed that undeclared animal species can be as common as missing an animal protein declared on the label. The conducted research indicates that both dry and wet analyzed foods should not be recommended as a diagnostic tool in elimination tests, because it may result in false negative results. Over-the-counter maintenance foods for dogs should not be recommended for the diagnosis and treatment of food hypersensitivity.
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Affiliation(s)
- Wioletta Biel
- Department of Monogastric Animal Sciences, Division of Animal Nutrition and Food, West Pomeranian University of Technology in Szczecin, 29 Klemensa Janickiego, 71-270, Szczecin, Poland
| | - Małgorzata Natonek-Wiśniewska
- Department of Animal Molecular Biology, National Research Institute of Animal Production, 1, Krakowska Street, 32-083, Balice, Poland
| | - Jagoda Kępińska-Pacelik
- Department of Monogastric Animal Sciences, Division of Animal Nutrition and Food, West Pomeranian University of Technology in Szczecin, 29 Klemensa Janickiego, 71-270, Szczecin, Poland.
| | - Katarzyna Kazimierska
- Department of Monogastric Animal Sciences, Division of Animal Nutrition and Food, West Pomeranian University of Technology in Szczecin, 29 Klemensa Janickiego, 71-270, Szczecin, Poland
| | - Ewa Czerniawska-Piątkowska
- Department of Ruminant Science, West Pomeranian University of Technology in Szczecin, Klemensa Janickiego 29, 71-270, Szczecin, Poland
| | - Piotr Krzyścin
- Department of Animal Molecular Biology, National Research Institute of Animal Production, 1, Krakowska Street, 32-083, Balice, Poland
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Konduru B, Sagi S, Parida M. Dry reagent-based multiplex real-time PCR assays for specific identification of chicken, mutton, beef and pork in raw and processed meat products. Eur Food Res Technol 2021. [DOI: 10.1007/s00217-020-03662-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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3
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Eischeid AC, Stadig SR, Rallabhandi P. Comparison of real-time PCR and ELISA for the detection of crustacean shellfish allergens. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2021; 38:563-572. [PMID: 33617420 DOI: 10.1080/19440049.2021.1874061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Food allergies are a significant public health concern, and crustacean shellfish represent one of the major FDA regulated food allergens. Allergic individuals must avoid foods containing crustaceans, and this necessitates highly sensitive and accurate detection methods. Two of the major methods used are protein-based ELISA and DNA-based real-time PCR. In order to properly compare these very different methodologies, we used identical split samples for a side-by-side comparison and analysed them using four different real-time PCR methods and two different commercial ELISA kits. Three real-time PCR assays targeting the mitochondrial 12S genes of shrimp, crab, and lobster were compared to a commercial ELISA assay for total crustacean protein. A fourth real-time PCR assay targeting the tropomyosin gene of shrimp was compared to an ELISA assay for shrimp tropomyosin. All comparisons were carried out in two different food matrices: Manhattan clam chowder and fish sauce. PCR assays had a more broad dynamic range (0.1-106 mg/kg) as compared to ELISA (200-4000 mg/kg) and did not show matrix interference like ELISA. In cases where the ELISA assays did not have matrix interference, there was good qualitative agreement between PCR and ELISA.
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Affiliation(s)
- Anne C Eischeid
- Department is Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland, USA
| | - Sarah R Stadig
- Department is Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland, USA
| | - Prasad Rallabhandi
- Department is Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland, USA
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He H, Wang Y, Qing Y, Li D, Zhao X, Zhu Q, Yin H. Molecular Authentication of Meats from Three Terrestrial Birds Based on Pcr-Rflp Analysis of the Mitochondrial 12S rRNA Gene. BRAZILIAN JOURNAL OF POULTRY SCIENCE 2018. [DOI: 10.1590/1806-9061-2017-0647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- H He
- Sichuan Agricultural University, China
| | - Y Wang
- Sichuan Agricultural University, China
| | - Y Qing
- Sichuan Agricultural University, China
| | - D Li
- Sichuan Agricultural University, China
| | - X Zhao
- Sichuan Agricultural University, China
| | - Q Zhu
- Sichuan Agricultural University, China
| | - H Yin
- Sichuan Agricultural University, China
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5
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Fossati LA, Larsen JA, Villaverde C, Fascetti AJ. Determination of mammalian DNA in commercial canine diets with uncommon and limited ingredients. Vet Med Sci 2018; 5:30-38. [PMID: 30375199 PMCID: PMC6376140 DOI: 10.1002/vms3.125] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Over‐the‐counter (OTC) limited ingredient canine diets could be reliable alternatives to veterinary therapeutic formulations for the diagnosis and management of adverse food reaction (AFR). However, the possibility of undeclared ingredients jeopardizes the efficacious use of OTC options for medical purposes. The objective was to determine the presence of undeclared ingredients in OTC canine dry diets marketed as limited or single protein source diets. Twenty‐one OTC adult canine diets marketed as limited or single protein source diets were purchased. Multiplex PCR was used to screen for DNA of 10 mammalian species with species‐specific primers that anneal to regions of the mitochondrial cytochrome b gene. The presence of DNA from one or more species not declared on the label was identified in all 21 diets: cow (Bos taurus), pig (Sus scrofa), sheep (Ovis sp.), goat (Capra hircus) and bison (Bison bison). Twenty diets were positive for the declared protein source and one diet was negative for the declared species. Cat (Felis catus), dog (Canis sp.), horse (Equus sp.), mouse (Mus musculus) and rat (Rattus norvegicus) DNA was not identified in any samples. The presence of undeclared mammal species in OTC canine dry diets marketed as having limited or single protein source ingredients may complicate AFR diagnosis and treatment. However, PCR can detect a miniscule amount of DNA which might not be clinically significant, because the amount needed to elicit a response is unknown. Quantification of the contamination was not determined in this study, precluding discrimination of intentional adulteration from unavoidable cross‐contamination.
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Affiliation(s)
- Lara A Fossati
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - Jennifer A Larsen
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - Cecilia Villaverde
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - Andrea J Fascetti
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA
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Pagani E, Soto Del Rio MDLD, Dalmasso A, Bottero MT, Schiavone A, Prola L. Cross-contamination in canine and feline dietetic limited-antigen wet diets. BMC Vet Res 2018; 14:283. [PMID: 30208880 PMCID: PMC6136174 DOI: 10.1186/s12917-018-1571-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 08/16/2018] [Indexed: 11/25/2022] Open
Abstract
Background Adverse food reactions (AFRs) are defined as abnormal responses to an ingested food or food additive. Diagnosis and treatment of AFRs consist of the complete elimination of these ingredients in the dietary trial. Previous studies have demonstrated the presence of undeclared ingredients in commercial limited-antigen dry food diets that can compromise the results and efficacy of dietary elimination trails. The aim of this study was to assess a selection of commercial canine and feline dietetic limited-antigen wet foods for the potential cross-contamination of animal proteins from origins not mentioned on the label. Results Eleven canine and feline dietetic limited-antigen wet foods (9 novel animal protein foods, 1 vegetarian and 1 hydrolyzed) were analyzed by polymerase chain reaction (PCR) to detect the presence DNA of animal and vegetal origins. PCR analysis confirmed the contamination of 6 of the 11 (54.5%) limited-antigen wet diets with undeclared animal protein. One of these 6 diets was solely composed of animal protein sources completely unrelated to those declared on the label. None of the foods containing horse meat or fish were contaminated, and neither were the vegetarian or the hydrolyzed food products. Moreover, the results show that had zoological class primers only been used to check for cross-class contaminations, as are generally used in the pet food industry for in-house checks, the apparent contamination rate would have been significantly underestimated: less than 20% (3/11), instead of the actual rate of 54.7% using species-specific primers. Conclusion This study reveals a high rate of cross-contamination in dietetic limited-antigen wet canine and feline foods, as previously described for dietetic dry limited-antigen foods (reported to be more than 80%). These results add new fuel to the discussion about the potential causes underlying the failure of elimination diets, since animal protein contaminants may actually be present in the commercial dietetic limited-antigen diets. AFRs may therefore occur as a result of inadequate practices in the pet food industry.
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Affiliation(s)
- Elena Pagani
- Department of Veterinary Sciences, University of Turin, L.go Braccini, 2, 10095, Turin, Grugliasco (TO), Italy.
| | | | - Alessandra Dalmasso
- Department of Veterinary Sciences, University of Turin, L.go Braccini, 2, 10095, Turin, Grugliasco (TO), Italy
| | - Maria Teresa Bottero
- Department of Veterinary Sciences, University of Turin, L.go Braccini, 2, 10095, Turin, Grugliasco (TO), Italy
| | - Achille Schiavone
- Department of Veterinary Sciences, University of Turin, L.go Braccini, 2, 10095, Turin, Grugliasco (TO), Italy
| | - Liviana Prola
- Department of Veterinary Sciences, University of Turin, L.go Braccini, 2, 10095, Turin, Grugliasco (TO), Italy
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Matricoti I, Noli C. An open label clinical trial to evaluate the utility of a hydrolysed fish and rice starch elimination diet for the diagnosis of adverse food reactions in dogs. Vet Dermatol 2018; 29:408-e134. [PMID: 30141280 DOI: 10.1111/vde.12680] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2018] [Indexed: 11/30/2022]
Abstract
BACKGROUND The diagnosis of adverse food reaction (AFR) is based on an eight week elimination diet (ED) and is confirmed by relapse upon re-challenge with the previously fed diet. Hydrolysed EDs are commonly used for this purpose. OBJECTIVE To evaluate a commercially available hydrolysed fish protein and rice starch ED for the diagnosis of AFR. ANIMALS Fifty nonseasonally pruritic dogs. METHODS AND MATERIALS Pruritus was assessed with a Visual Analog Scale, lesions with the Canine Atopic Dermatitis Lesions Index and quality of life with a validated questionnaire on days 0 and 56. Antimicrobial treatments were permitted during the first four weeks, and corticosteroids and oclacitinib during the first six weeks. Dogs showing at least 50% pruritus improvement were separately challenged with their prior diet, fish and rice. RESULTS Thirty eight dogs completed the ED, four were dropped out due to worsening clinical signs, three to low palatability and five were lost to follow-up. In 24 dogs, pruritus improved by >50% and 22 underwent dietary challenges. Of these, 15 reacted to their prior diets and were diagnosed with AFR, whereas seven did not relapse (and a diagnosis of AFR was considered to be doubtful). Five dogs reacted to fish and four to rice. Of the 14 dogs in which pruritus did not improve, some underwent a second ED and others were successfully treated for atopic dermatitis. CONCLUSION AND CLINICAL IMPORTANCE The hydrolysed fish and rice diet seemed to be a useful ED for the diagnosis of AFR, even in dogs allergic to fish or rice.
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Affiliation(s)
- Irina Matricoti
- Servizi Dermatologici Veterinari, Via Santo Stefano 168, 40125, Bologna, Italy
| | - Chiara Noli
- Servizi Dermatologici Veterinari, Strada Bedale della Ressia 2, 12016, Peveragno, Italy
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Hołda K, Natonek-Wiśniewska M, Krzyścin P, Głogowski R. Qualitative and quantitative detection of chicken deoxyribonucleic acid (DNA) in dry dog foods. J Anim Physiol Anim Nutr (Berl) 2018; 102 Suppl 1:37-42. [PMID: 29623687 DOI: 10.1111/jpn.12887] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 02/15/2018] [Indexed: 11/28/2022]
Abstract
Chicken is a common protein source in pet foods and is concurrently listed among food allergens. Commercial over-the-counter (OTC) diets with an alternative animal protein source are considered suitable for dietary elimination trials by pet owners. The potential presence of undeclared chicken-derived ingredients in these diets can compromise the outcome of the trial during the diagnosis of adverse food reactions. The aim of this study was to selectively verify the absence or presence of chicken DNA in 10 OTC dry canine foods, using qualitative and quantitative approaches. The method of identification of chicken-derived protein was elaborated with the polymerase chain reaction (PCR) technology, whereas quantitative real-time PCR was used for the quantitative assessment. In most of the analysed samples, the chicken DNA was detectable; however, the quantified amounts were predominantly low, although differences between batches were observed.
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Affiliation(s)
- K Hołda
- Department of Animal Breeding and Production, Faculty of Animal Sciences, Warsaw University of Life Sciences, Warsaw, Poland
| | - M Natonek-Wiśniewska
- Department of Genomics and Animal Molecular Biology, National Research Institute of Animal Production, Balice, Poland
| | - P Krzyścin
- Department of Genomics and Animal Molecular Biology, National Research Institute of Animal Production, Balice, Poland
| | - R Głogowski
- Department of Animal Breeding and Production, Faculty of Animal Sciences, Warsaw University of Life Sciences, Warsaw, Poland
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Olivry T, Mueller RS. Critically appraised topic on adverse food reactions of companion animals (5): discrepancies between ingredients and labeling in commercial pet foods. BMC Vet Res 2018; 14:24. [PMID: 29357847 PMCID: PMC5778722 DOI: 10.1186/s12917-018-1346-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 01/14/2018] [Indexed: 11/25/2022] Open
Abstract
Background
Elimination dietary trials for the diagnosis of adverse food reactions (food allergies) in dogs and cats are often conducted with commercial pet foods while relying on their label to select those not containing previously-eaten ingredients. There are concerns that industrial pet foods might contain unlisted food sources that could negate the usefulness of performing food trials. Furthermore, unidentified ingredients might cause clinical reactions in patients hypersensitive to such items.
Results
We searched two article databases on July 7, 2017 and January 12, 2018 for relevant articles, and we screened abstracts from the leading international veterinary dermatology congresses for suitable material. Additional citations were found in the selected papers. In all, we extracted data from 17 articles and one abstract. The studies varied both in the number of pet foods tested (median: 15; range: 1 to 210) and that of ingredients specifically evaluated (median: 4; range: 1 to 11). Studies most often employed either PCR to detect DNA or ELISA to identify proteins from one or more vegetal or animal species; two studies used mass spectrometry to increase the number of detectable proteins. The various methods found ingredients that were not on the label in 0 to 83% (median: 45%) of tested diets; this percentage varied between 33 and 83% in pet foods with “novel/limited” ingredients proposed for elimination diets. Similarly, ingredients were found to be missing from the label in 0 to 38% (median: 1%) of tested foods. Finally, six studies evaluated, among others, several hydrolysate-containing pet foods: mislabeling with unlabeled or missing ingredients was found only in one diet.
Conclusions
The mislabeling of pet foods appears rather common, even in those with “novel” or “limited” ingredients proposed for elimination diets. Unexpected added ingredients are more frequently detected than those missing from the label. There is insufficient information to determine if the presence of a contaminating component will lead to a clinical reaction in a patient allergic to it, as challenges with the mislabeled foods were not performed in dogs or cats allergic to such ingredients. The testing of hydrolysate-containing pet foods found only one instance of possible mislabeling.
Electronic supplementary material The online version of this article (10.1186/s12917-018-1346-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Thierry Olivry
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, NC, 27607, USA.
| | - Ralf S Mueller
- Medizinische Kleintierklinik, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University, Veterinärstrasse 13, 80539, Munich, Germany
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Lian DS, Zeng HS. Capillary Electrophoresis Based on Nucleic Acid Detection as Used in Food Analysis. Compr Rev Food Sci Food Saf 2017; 16:1281-1295. [DOI: 10.1111/1541-4337.12297] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/14/2017] [Accepted: 07/19/2017] [Indexed: 12/21/2022]
Affiliation(s)
- Dong-Sheng Lian
- Guangzhou Women and Children's Medical Center of Guangzhou Medical University; NO. 9 at Jinsui Rd., Tianhe District Guangzhou Guangdong China
| | - Hua-Song Zeng
- Guangzhou Women and Children's Medical Center of Guangzhou Medical University; NO. 9 at Jinsui Rd., Tianhe District Guangzhou Guangdong China
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Horvath-Ungerboeck C, Widmann K, Handl S. Detection of DNA from undeclared animal species in commercial elimination diets for dogs using PCR. Vet Dermatol 2017; 28:373-e86. [PMID: 28247445 DOI: 10.1111/vde.12431] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND Elimination diets are the gold standard for the diagnosis of adverse food reactions (AFR). A broad variety of commercial diets are available containing either hydrolysed protein or novel ingredients which claim to be suitable for elimination diets. Contamination may be one factor accounting for the failure of commercial elimination diet trials. HYPOTHESIS/OBJECTIVES To test commercial diets labelled as suitable for elimination diets for dogs, for DNA of animal origin other than that declared on the label. METHODS Twelve commercial dry and tinned dog food products were investigated for DNA of animal origin (chicken, turkey, beef, mutton and pork) using PCR testing. RESULTS In nine of 10 over-the-counter diets, DNA of one or more animal species other than declared on the label was identified. The DNA most frequently detected was derived from beef (n = 8) and pork (n = 6). Two hydrolysed diets only contained DNA of the declared animal source. CONCLUSIONS AND CLINICAL IMPORTANCE Over-the-counter "single protein diets" or canned meat products cannot be recommended for the diagnosis of dogs with AFR because contamination may cause the elimination diet to fail.
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Affiliation(s)
- Christa Horvath-Ungerboeck
- Clinical Unit of Internal Medicine Small Animals, Department for Companion Animals and Horses, University Clinic for Small Animals, University of Veterinary Medicine, Veterinaerplatz 1, 1210, Vienna, Austria
| | - Karoline Widmann
- Clinical Unit of Internal Medicine Small Animals, Department for Companion Animals and Horses, University Clinic for Small Animals, University of Veterinary Medicine, Veterinaerplatz 1, 1210, Vienna, Austria
| | - Stefanie Handl
- Futterambulanz nutritionist practice, Strohgasse12/15, 1030, Vienna, Austria
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12
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Nikzad J, Shahhosseini S, Tabarzad M, Nafissi-Varcheh N, Torshabi M. Simultaneous detection of bovine and porcine DNA in pharmaceutical gelatin capsules by duplex PCR assay for Halal authentication. ACTA ACUST UNITED AC 2017; 25:3. [PMID: 28196517 PMCID: PMC5310068 DOI: 10.1186/s40199-017-0171-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/09/2017] [Indexed: 01/09/2023]
Abstract
Background In the pharmaceutical industry, hard- and soft-shelled capsules are typically made from gelatin, commonly derived from bovine and porcine sources. To ensure that pharmaceutical products comply with halal regulations in Muslim countries (no porcine products allowed), development of a valid, reliable, quick, and most importantly, cost-effective tests are of utmost importance. Methods We developed a species-specific duplex polymerase chain reaction (PCR) assay targeting 149 bp porcine and 271 bp bovine mitochondrial DNA (mtDNA) to simultaneously detect both porcine and bovine DNA (in one reaction at the same time) in gelatin. Some additional simplex PCR tests (targeting 126 bp bovine and 212 bp porcine mtDNA) and real-time PCR using a commercially available kit (for identification of porcine DNA) were used to verify the selectivity and sensitivity of our duplex PCR. After optimization of DNA extraction and PCR methods, hard/soft pharmaceutical gelatin capsules (containing drug) were tested for the presence of porcine and/or bovine DNA. Results Duplex PCR detected the presence of as little as 0.1% porcine DNA, which was more accurate than the commercially available kit. Of all gelatin capsules tested (n = 24), 50% contained porcine DNA (pure porcine gelatin alone or in combination with bovine gelatin). Conclusions Duplex PCR presents an easy-to-follow, quick, low-cost and reliable method to simultaneously detect porcine and bovine DNAs (>100 bp) in minute amounts in highly processed gelatin-containing pharmaceutical products (with a 0.1% sensitivity for porcine DNA) which may be used for halal authentication. Graphical abstract Simultaneous detection of porcine and bovine DNA in gelatin capsules by duplex PCR ![]()
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Affiliation(s)
- Jafar Nikzad
- School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Soraya Shahhosseini
- Department of Pharmaceutical Chemistry, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Maryam Tabarzad
- Protein Technology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Nastaran Nafissi-Varcheh
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Maryam Torshabi
- Department of Dental Biomaterials, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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13
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Kanakubo K, Fascetti AJ, Larsen JA. Determination of mammalian deoxyribonucleic acid (DNA) in commercial vegetarian and vegan diets for dogs and cats. J Anim Physiol Anim Nutr (Berl) 2016; 101:70-74. [PMID: 27020325 DOI: 10.1111/jpn.12506] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/03/2016] [Indexed: 11/28/2022]
Abstract
The determination of undeclared ingredients in pet food using different analytical methods has been reported in recent years, raising concerns regarding adequate quality control, dietary efficacy and the potential for purposeful adulteration. The objective of this study was to determine the presence or absence of mammalian DNA using multiplex polymerase chain reaction (PCR) on diets marketed as vegetarian or vegan for dogs and cats. The diets were tested in duplicate; two samples were purchased approximately 3 to 4 months apart with different lot numbers. Multiplex PCR-targeted mitochondrial DNA with two species-specific primers was used to amplify and sequence two sections of the cytochrome b gene for each of the 11 mammalian species. Half of the diets assessed (7/14) were positive for one or more undeclared mammalian DNA source (bovine, porcine, or ovine), and the result was repeatable for one or more species in six diets. While most of the detected DNA was found at both time points, in some cases, the result was positive only at one time point, suggesting the presence may have been due to unintentional cross-contact with animal-sourced ingredients. DNA from feline, cervine, canine, caprine, equine, murine (mouse and rat) and leporine was not identified in any samples. However, evidence of mammalian DNA does not confirm adulteration by the manufacturer nor elucidate its clinical significance when consumed by animals that may benefit from a vegetarian or vegan diet.
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Affiliation(s)
- K Kanakubo
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA
| | - A J Fascetti
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA
| | - J A Larsen
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA
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