Sainsbury's Complete Nutrition Worker Dry review

This food lands in our Poor band, some way below the Good band that holds the typical adult dry food. What drives it is disclosure. The panel gives a figure for the chicken and a figure for the peas, and none at all for the meat and animal derivatives block sitting between them. That leaves the animal share of the recipe unreadable from the pack. Put cereals and oils and fats around that, neither of them named to a source, and there is very little here a careful reader can check. The analysis itself is ordinary, and nothing worse than that. A working dog fed on it will get the energy it came for.

Ingredients, as declared: Cereals, Meat and Animal Derivatives 4% Chicken), Oils and Fats, Vegetables (0.5% Dried Peas equivalent to 4% Peas), Minerals.

The ingredients panel runs to five entries: cereals, meat and animal derivatives with chicken at 4%, oils and fats, vegetables as 0.5% dried peas, and minerals. Read from the top that puts grain at the base with the animal content second, but no percentage is printed against the animal block itself, so exactly how far second it comes is left open.

The words meat and animal derivatives are a legal category. They are not a description. It takes in the fleshy parts and by-products of warm blooded land animals, from good material to poor, and it names no species. For a working dog with a cast iron stomach that will rarely matter. It matters a great deal when one particular meat is being kept out of a dog's bowl.

Oils and fats is working harder here than in the rest of the range. Fat is declared at 11.0% as fed, converting to 12.0% of dry matter on the 8% moisture a kibble usually carries. The term covers animal and plant fats alike and names neither. This is still the entry that gives the recipe its working character, since fat is the densest energy a dog can eat.

Protein reads 21.0%, or 22.8% of dry matter, and the rest of the panel gives fibre at 3.3%, ash at 8.2% and estimated carbohydrate at 53.7% on the same basis. Energy comes out at 339 kcal per 100g. Protein at 22.8% of dry matter is middling for a dog in genuine work. A hard season is a reason to raise the portion, not to lean on the bowl as it stands.

Vitamins A, D3 and E are dosed at 17000 IU, 1500 IU and 70mg, with zinc at 100mg, iron at 60mg, manganese at 50mg and copper at 8mg. Selenium comes as sodium selenite and iodine as calcium iodate, both of them the standard mineral salt forms.

£0.75 a kilo, sold in a 12kg bag.

As a guide, a 15kg adult dog in moderate condition eats about 248 grams a day, coming to roughly £0.19 a day. The day rate rests on around 840 kcal a day (110 × bodyweight^0.75, the standard maintenance estimate). In real work a dog will need more than that. The pack's own guide asks 195 to 445 grams for a dog of 10kg to 30kg, and on a busy week the top of that range is the part to look at.