Identifying the composition of commercial Brazilian cat food with stable isotopes of carbon and nitrogen

ABSTRACT

Considering the increasing pet owner’s concern about the food their pets are consuming, in this study we investigated the origin of the main ingredients in wet and dry foods produced in Brazil using stable isotope ratios of carbon and nitrogen. We concluded that chicken and pork seem to be the dominant ingredients in most of the samples, with larger proportions in wet cat food. Even in pet foods showing ‘beef’ as the main ingredient on the label, we found a low proportion of bovine products in both wet and dry cat foods. Comparing the contribution of plant-derived products (C₃ and C₄ plants) and animal-derived products (chicken–pork, bovine and fish), approximately 21 % of cat foods had more than 30 % of ingredients with plant origin in their composition. The high amount of plant-derived products in cat foods found here raises the question whether this should be mentioned on package labels.

KEYWORDS:

• Brazil
• carbon-13
• cats
• food
• MixSIAR model
• nitrogen-15
• origin of food ingredients pet food market
• tracer mixing model

Acknowledgements

The authors thank Amin Soltangheisi and Jim Hesson from the Academic English Solutions for kindly reviewing the English language, and the technicians of the Laboratory of Isotopic Ecology, Fabiana Fracassi, Isadora Ottani, and Maria Antônia Z. Perez for the analysis.

Disclosure statement

No potential conflict of interest was reported by the author(s).