Fresh animal blood

Blood collected at slaughterhouses, a protein-rich by-product used dried as blood meal or fresh in ferments.

Characteristics

Dried, it is one of the richest non-synthetic nitrogen sources, about 13 %.
Also contains small amounts of phosphorus and potassium.
Very rich in proteins, which microorganisms break down into nitrogen forms.
Cited in traditional biol recipes as a protein and nitrogen source.

Role in the preparation: It supplies organic nitrogen and proteins that break down during fermentation of the preparation.

Caution: Perishable material with health risks: obtain it only from an authorized source, handle with gloves, ferment in a closed container, and follow animal by-product regulations.

Sources: Blood meal - Wikipedia

Documentary information: this is neither a recommendation for use nor a plant-protection or veterinary claim. Check your country's regulations before any use.