The scores
Purina Pro Plan Adult Chicken & Rice: C (62/100) — Average. Chicken first, rice second, poultry by-product meal third. Includes probiotics (Bacillus coagulans) and fish oil, but leans heavily on soybean meal and corn protein meal.
Bil-Jac Adult Select: C (59/100) — Below average. Chicken first, chicken by-products second, followed by two forms of corn. Proprietary “NutriMax” slow-baking preserves more palatability but can’t offset by-product and split corn content.
A 3-point gap at the low end of C territory. Both brands sit well below the B-tier, and neither delivers what premium formulas do on animal-protein density. The choice between them is about which set of compromises you can live with — not which one is genuinely good.
How the ingredients compare
The top five ingredients show the nature of each formula:
Purina Pro Plan: Chicken, Rice, Poultry By-Product Meal, Soybean Meal, Corn Protein Meal
Bil-Jac: Chicken, Chicken By-Products, Corn Meal, Ground Corn, Chicken Digest
Both start with chicken — a whole named animal protein. That’s where the ingredient quality conversation ends favorably for both brands. Pro Plan follows with rice (a digestible carb) and then poultry by-product meal (an unnamed-species by-product), then shifts to soybean meal and corn protein meal — two plant-based protein boosters that pad the guaranteed-analysis protein percentage.
Bil-Jac takes a different filler route. Position two is chicken by-products (slightly better than Pro Plan’s generic poultry by-product meal because the species is named), but positions three and four are both corn: corn meal and ground corn. This is textbook ingredient splitting — listing a single base ingredient under two names so each appears lower on the list individually. Combined, corn is likely the single largest ingredient category in the formula by weight. Chicken digest at position five is a palatability enhancer sprayed on the kibble, not a primary nutrition source.
Neither formula uses cheap unnamed fillers like “meat and bone meal.” Both avoid BHA and BHT. Both list whole chicken first. The differences show up in what follows — and in the functional additions deeper in each formula.
Where Purina Pro Plan pulls ahead
Probiotics. Pro Plan includes Bacillus coagulans, a spore-forming probiotic specifically selected to survive extrusion heat and reach the gut alive. For a formula at this price point, that’s a meaningful functional addition. Bil-Jac doesn’t include any probiotics, relying instead on the natural digestibility of its slow-baked kibble.
Fish oil for omega-3s. Pro Plan includes fish oil, delivering EPA and DHA — marine-sourced omega-3 fatty acids that support joint health, coat quality, and cognitive function. Bil-Jac’s fat profile comes primarily from chicken fat, which lacks the marine omega-3s. For senior dogs or dogs prone to skin issues, Pro Plan’s inclusion matters.
No double-corn splitting. Pro Plan uses corn protein meal and whole grain corn — a different ingredient-splitting pattern, but with fewer corn derivatives than Bil-Jac’s corn-meal-plus-ground-corn combo. The overall corn load is comparable, but Pro Plan’s formula doesn’t telegraph the splitting as obviously.
More varied grain base. Rice as the second ingredient gives Pro Plan a more digestible carbohydrate foundation than Bil-Jac’s corn-first approach. Rice is well-tolerated by most dogs and is a staple in many veterinary GI recovery diets. Shop on Amazon →
Where Bil-Jac holds its own
Named chicken by-products vs generic poultry by-product meal. Bil-Jac’s second ingredient is chicken by-products — the species is named. Pro Plan’s equivalent ingredient is poultry by-product meal, which could come from any poultry species (chicken, turkey, duck) or mix of species. Neither is premium, but naming the source is a minor transparency win for Bil-Jac.
No soybean meal. Soybean meal in Pro Plan is a plant-based protein concentrate and one of the more common allergens in dogs. Bil-Jac skips soy entirely. For dogs with confirmed or suspected soy sensitivities, this matters.
Slow-baking and palatability. Bil-Jac uses a proprietary slow-baking process that reportedly preserves more of the natural flavors and textures that dogs find appealing. Anecdotally, picky eaters often accept Bil-Jac when they reject higher-quality foods. Palatability matters — the best food in the world is worthless if your dog won’t eat it. This is genuinely Bil-Jac’s strongest real-world advantage.
Family-owned, privately held. Bil-Jac has been family-owned since 1947. Pro Plan is a Nestlé-owned mass brand. For owners who prefer smaller, independent manufacturers, Bil-Jac offers that — though it’s worth noting that ownership structure doesn’t directly affect ingredient quality. Shop on Amazon →
The bottom line
Purina Pro Plan (C/62) wins this matchup over Bil-Jac (C/59) by a 3-point margin. The probiotics and fish oil are the difference — real functional additions that address digestive health and omega-3 supplementation. Bil-Jac’s slow-baking and palatability are genuine advantages for picky eaters, and the species-named by-products edge out Pro Plan’s generic version. But on overall ingredient quality, Pro Plan takes the narrow win.
That said, if you’re considering either of these, it’s worth asking whether a C-grade formula is the right choice in the first place. For similar money, Diamond Naturals (B/78) or Kirkland Signature (B/78) deliver dramatically better ingredient quality — real animal protein foundations without heavy corn or by-product reliance. The 3-point Pro Plan vs Bil-Jac gap is a footnote compared to the 16+ point gap to a genuine B-grade alternative.