As part of our resources for Coggins testing, we wanted to find, organize, and publish the rules and guidelines for packaging equine serum samples and shipping them to veterinary diagnostic labs. The USDA Animal and Plant Health Inspection Service (APHIS) provides informal guidelines for packaging and shipping Coggins test samples as well as other potentially infectious substances. If you’re looking for the official rules for packaging serum samples, the Government Publishing Office makes them available to the general public. See the sections on Category B infectious substances.
If you don’t need the formal rules, here is our cheat sheet of basic information and practical advice for shipping and packaging Coggins test samples. It starts with the three basic components of packaging test samples: the primary receptacle, secondary packaging, and rigid outer packaging.
1.Sealed Serum Sample Tubes (Primary Receptacle)
When submitting equine samples from a remote location, an authorizing veterinarian must draw the blood and prepare a sealed sample with essential information that ensures the chain-of-custody. To ensure accurate matching of blood samples, veterinarians must be prepared to provide the horse’s name, age, breed, sex, markings, stable, and owner. For clarity and quick identification at the lab, red-top vacuum sample tubes are recommended for serum samples with no additives. Here’s a handy online resource veterinarians and animal owners can use as a reminder of the color-coded blood tubes used for different types of lab samples. Most labs require serum samples between 1-2 ml, while the maximize size of the “primary receptacle” should not exceed one liter, according to federal guidelines.
2. Absorbent and Cushioning Materials (Secondary Packaging)
Immediately around the primary receptacle, you should add a layer of absorbent material. Cotton is recommended, but it’s not the only material you can use. Surrounding the absorbent layer should be another layer of cushioning materials, such as rags or packing peanuts. This cushioning material works as an extra layer of shock absorption. Only an extraordinary event should be able to pierce the box and damage the primary receptacle. And if it does, nothing should be able to leak back out of the packaging.
3. Shipping Boxes and Containers (Rigid Outer Packaging)
With a sealed primary receptacle and around the soft, absorbent layer should be rigid outer packaging. The basic rule-of-thumb with this rigid outer packaging is that, together with the weight and absorbent layer inside the packaging, it should be able to withstand a drop from 4 feet high. A cardboard box in good condition should work so long as you don’t skimp on the first two layers. Plastic shipping containers will also do the trick but are probably not cost-effective when shipping at a high volume. In addition to the name, address, and phone number of the shipper and the consignee, the box should be clearly labeled as “Biological Substance, Category B” along with the code for an animal specimen “UN3373.”

Picture from https://www.ncagr.gov/vet/ncvdl/LabUserGuide.pdf
Packaging Tips and Common Mistakes to Avoid
- Double- and triple-check your mailing labels and form information for typos. In talking to veterinary diagnostic labs around the country, it’s clear that the most common reason for a failed test submission is typographical errors and other misinformation.
- Be sure to visit the lab’s website or contact them directly for any unusual tips and advice about submitting samples and test requests. For example, many have different locations for their mailing address vs receiving address for lab samples. Many have shipping discounts negotiated through preferred carriers.
- Be sure to include dry ice or frozen gel packs. Don’t take it for granted that overnight express shipping during cold-weather season is enough to ensure your samples stay viable. But also be sure these packs are of sturdy construction and won’t leak.
- Avoid weekend delivery dates unless arrangements are made ahead of time. If the lab isn’t open, the samples may be left to the elements, the gel packs may be spent, or the package may not get delivered until the following business day.
- Don’t wrap forms around the specimen. If the sample tube is broken or damaged, the form may be damaged to the point of being illegible. In a worst-case scenario, the lab may not have sufficient information to notify the owner or veterinarian of the failed submission.