Mustard oil cake has several beneficial uses across agriculture and animal husbandry:

1. **Animal Feed Supplement**: It is widely used as a protein-rich feed supplement for livestock (cattle, buffaloes, goats, sheep) and poultry (chickens, ducks). The high protein content (30-32%) and essential amino acids help in growth, milk production (in dairy animals), and overall health maintenance.

2. **Organic Fertilizer**: Mustard oil cake is valued as an organic fertilizer due to its nitrogen content (about 4-5%) and other nutrients (such as phosphorus, potassium, and calcium). It improves soil fertility, enhances microbial activity, and promotes better nutrient uptake by plants.

3. **Soil Amendment**: When used as a fertilizer, mustard oil cake acts as a soil conditioner, improving soil structure, water retention, and aeration. It also helps in maintaining soil pH levels.

4. **Biopesticidal Properties**: Mustard oil cake contains glucosinolates, compounds known for their biopesticidal properties. When incorporated into the soil, it can help in managing soil-borne pests and diseases.

5. **Composting**: It can be used as a component in composting to accelerate decomposition and enrich the compost with nutrients, thus producing high-quality organic matter for soil improvement.

6. **Biogas Production**: In some regions, mustard oil cake is also used as a substrate for biogas production through anaerobic digestion, contributing to renewable energy generation.

Overall, mustard oil cake serves as a sustainable and valuable resource in agriculture, supporting both plant health through soil enrichment and animal nutrition through dietary supplementation.