What is the rule if there is contributory negligence on the part of the shipper?

General Rule:

If the shipper or owner merely contributed to the loss, destruction or deterioration of the goods, the proximate cause thereof being the negligence of the common carrier, the latter shall be liable for damages, which however, shall be equitably reduced. (Art. 1741)

Exception:

In a collision case and allision cases, the parties are liable for their own damages.