Short answer. Forty days from delivery. A redhibitory action based on the faults or defects of an animal must be brought within forty days counted from the date the animal was delivered to you. That is a far shorter window than the one that applies to ordinary goods, and it is easy to lose.
What the law says
The redhibitory action, based on the faults or defects of animals, must be brought within forty days from the date of their delivery to the vendee. This action can only be exercised with respect to faults and defects which are determined by law or by local customs.
Civil Code, Article 1577 — Prescription: Redhibitory Action for Animals (40 Days). Read the full provision →
Forty days, counted from delivery
The rule is unusually strict: The redhibitory action, based on the faults or defects of animals, must be brought within forty days from the date of their delivery to the vendee. Three points follow. The clock starts at delivery — not at payment, not at the signing of any receipt, and not on the day the animal finally shows symptoms. It is counted in days, so a sale on the first of the month is already past the deadline by the middle of the second. And the requirement is that the action be brought: telling the seller, sending a message, or arguing at the market is not the same as filing. Note the date of delivery in writing while you still remember it.
Not every fault counts
The article limits itself further. The action can only be exercised with respect to faults and defects which are determined by law or by local customs. In other words, the complaint must rest on a recognised defect — a condition that the law or the settled trade practice of the place treats as a vice in that kind of animal — and not merely on your disappointment. An animal that is smaller, slower, less productive or less handsome than you hoped is usually not a redhibitory defect at all. Because local custom does real work here, evidence about how the trade in your area treats the condition can matter as much as the veterinary report.
What redhibition actually gets you
Redhibition is the remedy that unwinds the sale: the animal goes back and the price comes back. Philippine law also allows a buyer facing a hidden defect to keep the thing and ask instead for a proportionate reduction of the price, and the choice between the two normally belongs to the buyer. What the remedy is not is an open-ended damages claim for every loss the animal caused. Keep the animal identifiable and, where it is safe and practical, keep it alive and available — a claim to return something you can no longer return is much harder to run, and a seller will not be slow to say so.
If the forty days have already gone
The lapse of the forty days closes this particular action; it does not automatically close every door. A seller who actively concealed a known disease, gave a written guarantee, or misdescribed the animal may be answerable on a different footing, and the periods for those claims are not the same. Sales by veterinary clinics, breeders and traders may also engage consumer protection rules. None of that is a reason to wait. The safest course when an animal you have just bought turns out to be sick is to get a veterinary examination on paper immediately, write to the seller the same week, and take advice on filing well inside the forty days rather than at the end of them.