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The short answer: Castor & Pollux Organix wins by 12 points (A/90 vs B/78). The interesting thing about this matchup: both brands are built around supply-chain credentials rather than ingredient-panel innovation. Castor & Pollux carries the USDA Organic seal across the top of its panel (federal certification, no synthetic pesticides on grain, no antibiotics in chicken supply chain). Tender & True carries G.A.P. (Global Animal Partnership) animal welfare certification on its chicken and avoids the corn-wheat-soy triad. Different credentials, different price points.

The scores

Tender & True Antibiotic-Free Chicken & Brown Rice: B (78/100) — Chicken, Chicken Meal, Brown Rice, Tapioca Starch, Potato Starch.

Castor & Pollux Organix Organix Organic Chicken & Brown Rice: A (90/100) — Organic Chicken, Organic Chicken Meal, Organic Oatmeal, Organic Barley, Organic Brown Rice.

How the ingredients compare

The top-five ingredients reveal the formulation split between these two brands:

Tender & True: Chicken, Chicken Meal, Brown Rice, Tapioca Starch, Potato Starch

Castor & Pollux: Organic Chicken, Organic Chicken Meal, Organic Oatmeal, Organic Barley, Organic Brown Rice

The 12-point gap (Castor & Pollux wins by 12 points) shows where the v15 rubric weights ingredient breadth, protein density, and supplement depth differently.

Where Tender & True pulls ahead

G.A.P. animal welfare certification: Tender & True’s chicken is raised to Global Animal Partnership welfare standards — an independent third-party audit framework (the same one Whole Foods uses). For owners who weigh animal welfare alongside ingredient quality but don’t need the USDA Organic price tier, this is the more accessible humane-sourcing credential. Shop on Amazon →

Marine omega-3 from two sources: Whitefish meal at #7 plus menhaden fish oil further down deliver directly-usable EPA and DHA. Castor & Pollux relies on organic flaxseed alone for omega-3 contribution, which carries the inefficient plant-ALA-to-EPA conversion bottleneck in dogs.

Lower price tier: Tender & True typically prices 30–45% below Castor & Pollux Organix per pound at retail. For owners who specifically value humane-sourcing over organic certification, this is the more accessible entry to the supply-chain-credential segment.

Where Castor & Pollux holds its own

USDA Organic federal certification: Castor & Pollux Organix carries USDA Organic on its entire ingredient lead — organic chicken, organic chicken meal, three organic whole grains, organic chicken fat. No synthetic pesticide residue on grain, no antibiotics or hormones in the poultry supply, no GMO inputs. Tender & True uses high-quality conventional grains and antibiotic-free chicken but does not carry USDA Organic. Shop on Amazon →

Whole-grain carbohydrate base: Organic brown rice, organic oatmeal, and organic barley supply the carbohydrate fraction. Tender & True relies on brown rice plus three refined starches (tapioca starch, potato starch, potato flour) — refined-starch fragments rather than whole-grain inclusion.

Pre-FDA-DCM-watchlist structure: Castor & Pollux’s organic-grain carbohydrate base is grain-inclusive with whole grains specifically (no peas, lentils, or potatoes in the top positions). For DCM-predisposed breeds (Dobermans, Goldens, Cocker Spaniels), this is the structurally safer carbohydrate profile.

The bottom line

Castor & Pollux Organix and Tender & True both lead with supply-chain credentials — they’re the rare pair where third-party certification rather than ingredient innovation drives the score. Castor & Pollux earns A/90 with USDA Organic federal certification across the panel and a whole-grain carbohydrate base. Tender & True earns B/78 with G.A.P. humanely-raised antibiotic-free chicken, marine omega-3 from whitefish meal and menhaden oil, and a more accessible price point. For owners who want certified organic supply chain regardless of price, Castor & Pollux is the answer. For owners who want humane-sourcing at retail-mainstream pricing, Tender & True is the answer.