Silkworm eggs

The quality of silkworm eggs (graine) is the foundation of sericulture success. Buyers must prioritize diapause-treated eggs if they are not for immediate hatching. Ensure the hatching rate is above 90% under standard incubation conditions. Physically, the eggs should be uniform in size, plump, and possess a slate-grey or dark purple color (for acid-treated or non-diapause varieties). Avoid batches with a high percentage of yellow (unfertilized) or collapsed eggs, as these indicate poor storage or low vigor.

Selection depends on the climate and desired silk quality. Bivoltine hybrids are generally preferred for high-grade international silk (3A-6A grade) due to their longer filament length and higher reelability, though they require stricter temperature control. Multivoltine varieties are hardier and suitable for tropical climates but produce shorter filaments. Ensure the supplier provides a technical data sheet specifying the incubation period (usually 9-11 days) and the expected cocoon shell ratio.

Silkworm eggs are biological materials and are strictly regulated. Suppliers must provide a Phytosanitary Certificate and a Certificate of Origin. It is critical to verify that the eggs are certified 'Pebrine-free'; Pebrine is a devastating microsporidian disease transmitted transovarially. Ensure the production facility follows ISO 9001 or local agricultural quality standards to prevent the spread of pathogens like Nuclear Polyhedrosis Virus (NPV).

Temperature control is the most critical factor in logistics. Eggs should be transported in breathable, specialized egg cards or loose-egg boxes within cold-chain packaging (maintained at 5°C to 10°C) to prevent premature hatching or metabolic exhaustion. For long-distance cross-border shipping, air freight is the only viable option. The packaging must include shock-absorption layers and clear labeling as 'Live Biological Material' to avoid delays at customs.

The biggest risk is Customs Quarantine Detention. If the required biological permits are missing, the shipment may be destroyed. Another risk is Temperature Fluctuations during transit, which can trigger 'dead eggs' or uneven hatching. To mitigate this, use data loggers inside the packaging to monitor temperature throughout the journey and choose suppliers on Made-in-China.com who have proven experience in biological exports.

Focus on Quality Guarantees rather than just price. Negotiate a replacement clause if the hatching rate falls below a specified threshold (e.g., 85%) upon arrival. For large-scale operations, request volume-based discounts (typically 10-20% for bulk orders) and ask for technical support services, such as guidance on incubation and rearing synchronization, which adds significant value to the transaction.

Always use Trade Assurance or Escrow services provided by reputable platforms like Made-in-China.com to ensure funds are only released upon confirmation of receipt and initial inspection. Conduct third-party pre-shipment inspections to verify the batch quantity and the presence of health certificates. Avoid direct wire transfers to unknown accounts without a verified business history.

Check your local Import Permit requirements for 'Insects and Biological Organisms' before placing an order. Some countries require an Import License issued by the Ministry of Agriculture. Ensure the supplier provides Invoices and Packing Lists that match the scientific name (Bombyx mori) and the specific variety to avoid classification errors that lead to heavy fines or shipment seizure.