The purpose of this study was to compare the in vitro digestibility levels and chemical compositions of commercial extruded dry-type adult dog foods with different types of protein contents [fish meat (F-dog foods) (n = 7), lamb meat (L-dog foods) (n = 9), or poultry meat (P-dog foods) (n = 8)]. The in vitro digestion values of premium commercial dog foods were examined at three stages: gastric digestion, small intestine digestion and large intestine digestion/fermentation. The metabolisable energy (ME), crude protein (CP), starch, diethyl ether extract (EE) and ash contents and the in vitro cumulative gas production values of all the premium dog foods differed significantly among the commercial brands in the same category (F-, L- or P-dog foods) (P < 0.05). The crude fibre (CF) and the CP/1 000 kcal ME values of the F- and P-dog foods demonstrated a significant difference among the commercial brands (P < 0.05). The organic matter disappearance (OMd) values of the L-dog foods showed a significant difference among the commercial brands (P < 0.05); but the OMd values of the F- and P-dog foods did not differ among the commercial brands (P > 0.05). The average values of the OMd for the F-dog foods were more rapid than the average for the L- and P-dog foods, in the evaluation of all the foods (P = 0.001). Besides, the price of the L-dog foods was positively correlated with the OMd and CP of the L-dog foods; however, it was negatively correlated with the NFE (nitrogen free extract) and CHO (total carbohydrates) of the L-dog foods (P < 0.05). The CP values of the L-dog foods were positively correlated with the OMd values (P < 0.05). Although price is an important determinant of food quality in the L-dog foods, it is not in the F- and P-dog foods. In the general evaluation of all the dog foods, there was no correlation among the food price and the digestibility and the nutrient content for all of the premium dog foods. The present study indicated that the energy, nutrient matter and digestibility of premium dog foods changed with the change in the variety and the amount of the feedstuffs. The digestibility of the dog foods with the fish meat were higher than those of the other dog foods. The amount of protein that an adult dog will receive with 1 000 kcal of DM (dry matter) consumption of premium dog foods with fish meat and chicken meat, varied among the brands. This point showed the need to pay attention to the food consumption amount of the dogs and the energy-protein balance in their diets, especially dog foods with fish meat and chicken meat.
AAFCO – Association of American Feed Control Officials. Pet feed regulation. Official publication. AAFCO methods for substantiating nutritional adequacy of dog and cat foods [Internet]. 2015 [cited 2020 Feb 14]. Available from https://www.aafco.org/Portals/0/SiteContent/Regulatory/Committees/Model-Bills-and-Regulations/Reports/MBRC_minutes_Attachment_A.pdf.
AOAC – Association of Official Analytical Chemists. Official methods of analysis [Internet]. 15th ed. 1990 [cited 2019 Oct 4]. Available from law.resource.org/pub/us/cfr/ ibr/002/aoac.methods.1.1990.pdf.
Bosch G, Pellikaan WF, Rutten PGP, van der Poel AFB, Verstegen MWA, Hendricks WH. Comparative in vitro fermentation activity in the canine distal gastrointestinal tract and fermentation kinetics of fiber sources. J Anim Sci. 2008 Nov;86(11):2979-89. https://doi.org/10.2527/jas.2007-0819
Buffington T, Holloway C, Abood S. Manual of veterinary dietetics. 1st ed. USA: Saunders; 2004.
Calabro S, Carciofi AC, Musco N, Tudisco R, Gomes MO, Cutrignelli MI. Fermentation characteristics of several carbohydrate sources for dog diets using the in vitro gas production technique. Ital J Anim Sci. 2013 Jan 1;12(1):e4. https://doi.org/10.4081/ijas.2013.e4
Carciofi AC, Vasconcellos RS, Borges NC, Moro JV, Prada F, Fraga VO. Nutritional composition and label evaluation of dry dog foods sold in Jaboticabal-SP. Arq Bras Med Vet Zootec. 2006 Jun;58(3):421-6. https://doi.org/10.1590/S0102-09352006000300021
Case LP, Daristotle L, Hayek MG, Raasch MF. Canine and feline nutrition: A resource for companion animal professionals. St. Louis: Mosby Elsevier; 2011. 562 p..
Colonna P, Leloup V, Buleon A. Limiting factors of starch hydrolysis. Eur J Clin Nutr. 1992 Oct;46 Suppl 2:S17-32.
Crane SW, Cowell CS, Stout NP, Moser EA, Millican J, Romano P, Crane SE. Chapter 8 – Commercial pet foods. In: Hand MS, Thatcher CD, Remillard RL, Roudebush P, Novotny BJ, editors. Small animal clinical nutrition. 5th ed. Topeka, Kansas: Mark Morris Institute; 2010. p. 156-90.
Daumas C, Paragon BM, Thorin C, Martin L, Dumon H, Ninet S, Nguyen P. Evaluation of eight commercial dog diets. J Nutr Sci. 2014 Dec 30;3:1-5. https://doi.org/10.1017/jns.2014.65
Earle KE, Kienzle E, Opitz B, Smith PM, Maskell IE. Fiber affects digestibility of organic matter and energy in pet foods. J Nutr. 1998 Dec;128(12 Suppl):2798S-800S. https://doi.org/10.1093/jn/128.12.2806S
Englyst HN, Kingman SM, Cummings JH. Classification and measurement of nutritionally important starch fractions. Eur J Clin Nutr. 1992 Oct;46(Suppl 2):S33-50.
FEDIAF – The European Pet Food Industry. Nutritional guidelines: For complete and complementary pet food for cats and dogs [Internet]. 2018 [cited 2020 Mar 10]. Available from: http://www.fediaf.org/images/FEDIAF_Nutritional_Guidelines_2019_Update_030519.pdf.
Godoy MRC, Kerr KR, Fahey GC. Alternative dietary fiber sources in companion animal nutrition. Nutrients. 2013 Aug 6;5(8):3099-117. https://doi.org/10.3390/nu5083099
Hall MB. Determination of dietary starch in animal feeds and pet food by an enzymatic-colorimetric method: Collaborative study. J AOAC Int. 2015 Mar 1;98(2):397-409. https://doi.org/10.5740/jaoacint.15-012
Heinze CR. Premium pet foods – are they worth the premium price? Petfoodology [Internet]. 2016 Oct [cited 2019 Oct 1]. North Grafton, MA, USA: Cummings Veterinary Medical Center at Tufts University. Available from: https://vetnutrition.tufts.edu/2016/10/should-you-buy-premium-pet-food/. https://doi.org/10.15420/usc.2016:3:2
Hervera M, Baucells MD, Blanch F, Castrillo C. Prediction of digestible energy content of extruded dog food by in vitro analyses. J Anim Physiol Anim Nutr (Berl). 2007 Jun;91(5-6):205-9. https://doi.org/10.1111/j.1439-0396.2007.00693.x
Kara K, Guclu BK, Baytok E. Comparison of fermentative digestion levels of processed different starch sources by Labrador Retrievers at different ages. Vet Med-Czech. 2019 Apr 23;64(4):158-71. https://doi.org/10.17221/105/2018-VETMED
Kirkwood JK. The influence of size on the biology of the dog. J Small Anim Pract. 1985 Feb;26(2):97-110. https://doi.org/10.1111/j.1748-5827.1985.tb02090.x
Lauten SD. Nutritional risks to large-breed dogs: From weaning to the geriatric years. Vet Clin North Am Small Anim Pract. 2006 Nov;36(6):1345-59. https://doi.org/10.1016/j.cvsm.2006.09.003
Meyer H, Kienzle E, Zentek J. Body size and relative weights of gastrointestinal tract and liver in dogs. J Vet Nutr. 1993;2:31-5.
NRC – National Research Council . Nutrient requirements and signs of deficiency. In: Nutrient requirements of dogs. Washington, D.C.: National Academies Press; 1985.
NRC – National Research Council. Nutrient requirements of dogs and cats.Washington D.C.: The National Academies Press; 2006. 424 p.
Rokey GJ, Plattner B, Souza EM. Feed extrusion process description. R Bras Zootec. 2010 Jul;39:510-8. https://doi.org/10.1590/S1516-35982010001300055
Silvio J, Harmon DL, Gross KL, McLeod KR. Influence of fiber fermentability on nutrient digestion in the dog. Nutrition. 2000 Apr;16(4):289-95. https://doi.org/10.1016/S0899-9007(99)00298-1
Sunvold GD, Fahey GC, Merchen NR, Titgemeyer EC, Bourquin LD, Bauer LL, Reinhart GA. Dietary fiber for dogs: IV. In vitro fermentation of selected fiber sources by dog fecal inoculum and in vivo digestion and metabolism of fiber-supplemented diets. J Anim Sci. 1995a Apr;73(4):1099-109. https://doi.org/10.2527/1995.7341099x
Sunvold GD, Hussein HS, Fahey GC, Merchen NR, Reinhart GA. In vitro fermentation of cellulose, beet pulp, citrus pulp, and citrus pectin using fecal inoculum from cats, dogs, horses, humans, and pigs and ruminal fluid from cattle. J Anim Sci. 1995b Dec;73(12):3639-48. https://doi.org/10.2527/1995.73123639x
Urrego MI, Ernandes MC, de Oliveira Matheus LF, de Melo Santos K, Oba PM, Silva CG, Vendramini TH, Pedrinelli V, Brunetto MA. Nutritional composition and evaluation of different methodologies for fat determination in wet feed for dogs and cats. Braz J Vet Res Anim Sci. 2017 Dec 31;54(4):398-406. https://doi.org/10.11606/issn.1678-4456.bjvras.2017.133279
Walter RH, Rao MA, Sherman RM, Cooley HJ. Edible fibers from apple pomace. J Food Sci. 1985 May;50(3):747-9. https://doi.org/10.1111/j.1365-2621.1985.tb13787.x
Weber M, Martin L, Biourge V, Nguyen P, Dumon H. Influence of age and body size on the digestibility of a dry expanded diet. J Anim Physiol Anim Nutr (Berl). 2003 Feb;87(1-2):21-31. https://doi.org/10.1046/j.1439-0396.2003.00410.x