Using Pet Food as the Subject to Investigate the Effectiveness of Whole-Genome Sequencing in the Authentication of Highly Processed Complex Food

Analysis of chicken and pig DNA content in commercial dry foods for adult cats

Among pets, cats are the most popular in Europe. Despite the fact, the interest in the safety and quality of their food is much lower compared to the interest of caregivers in the nutrition of dogs. In this research, 27 commercial cat foods were analyzed for mislabeled component composition. Cat foods were divided into a control group, a group of fish foods and a group of other foods with alternative sources of animal protein. Chicken and pig DNA detection was performed using real-time PCR. In this research, 100% of the cat foods contained chicken DNA and 96% of the foods - pig DNA, despite the lack of declaration of these ingredients on the product label. The results indicate that cat food appear to be mislabeled to an even greater extent than dog food. Moreover, manufacturers' declarations in terms of ingredient composition do not reflect the actual composition of commercial products available on the market and intended for everyday feeding of animals. Mislabeling of these products also poses a risk for animals suffering from food allergies.

DNA mini-barcoding reveals the mislabeling rate of canned cat food in Taiwan

Background

Domestic cats are important companion animals in modern society that live closely with their owners. Mislabeling of pet food can not only harm pets but also cause issues in areas such as religious beliefs and natural resource management. Currently, the cat food market is booming. However, despite the risk that mislabeling poses to cats and humans, few studies have focused on species misrepresentation in cat food products.

Methods

To address this issue, we used DNA barcoding, a highly effective identification methodology that can be applied to even highly processed products. We targeted a short segment (~85 basepairs) of the mitochondrial 16S rRNA (16S) gene as a barcode and employed Sanger or next generation sequencing (NGS) to inspect 138 canned cat food products in the Taiwanese market.

Results

We discovered that the majority of mislabeling incidents were related to replacement of tuna with other species. Moreover, our metabarcoding revealed that numerous undeclared ingredients were present in all examined canned products. One product contained CITES Appendix II-listed shortfin mako shark (Isurus oxyrinchus). Overall, we uncovered a mislabeling rate of at least 28.99%. To verify cases of mislabeling, an official standardized list of vernacular names, along with the corresponding scientific species names, as well as a dependable barcoding reference sequence database are necessary.