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SNAP FeLV Antigen Test Kit

This page contains information on SNAP FeLV Antigen Test Kit for veterinary use.
The information provided typically includes the following:
  • SNAP FeLV Antigen Test Kit Indications
  • Warnings and cautions for SNAP FeLV Antigen Test Kit
  • Direction and dosage information for SNAP FeLV Antigen Test Kit

SNAP FeLV Antigen Test Kit

This treatment applies to the following species:
Company: Idexx Labs.

Feline Leukemia Virus Antigen Test Kit

For veterinary use only.


SNAP FeLV Antigen test is an enzyme-linked immunosorbent assay (ELISA) for the detection of feline leukemia virus (FeLV) antigen in feline serum, plasma or whole blood. The detection of the FeLV group-specific viral antigen (p27) is diagnostic for FeLV infection. The SNAP FeLV Antigen assay utilizes monoclonal antibodies to p27 and positive and negative controls.

The conjugate contains enzyme-conjugated antibody to p27. Upon mixing the conjugate and the test sample, conjugated monoclonal antibody will bind p27 antigen (if present). The sample/conjugate mixture is then added to the SNAP device and flows across the spotted matrix. The matrix-bound p27 antibody (FeLV spot) will capture the p27-conjugated antibody complex. The device is then activated, releasing wash and substrate reagents stored within the device.

Color development in the FeLV Ag sample spot indicates the presence of FeLV antigen.

Precautions and warnings

● Use a separate sample tube and transfer pipet for each test.

● During manufacturing the bioactive spots are dyed for quality control purposes. This does not interfere with the test results or interpretation.

● Samples, sample tubes, pipettes, conjugate and SNAP devices should be handled as though capable of transmitting FeLV. All waste should be properly decontaminated prior to disposal.

● Do not use kit past expiration date and do not intermix components from kits with different serial numbers.

● The SNAP device must be in a horizontal position on a flat surface while performing test.

● Do not use a SNAP device that has been activated prior to the addition of sample.

WARNING: Conjugate - H316/P332+P313/EUH208. Causes mild skin irritation. If skin irritation occurs: Get medical advice/attention. Contains ProClin™ 150. May produce an allergic reaction.


● SNAP devices and test reagents must be stored at 2-8°C.

Kit components




15 Test


30 Test


1 bottle Anti-FeLV: HRPO Conjugate (Preserved with gentamicin and ProClin™ 150)

3.5 mL

7 mL


SNAP Device - Monoclonal antibodies to p27 and positive and negative controls



Reagents contained in each device:



Wash Solution (preserved with ProClin™ 150)

0.4 mL

0.4 mL

Substrate Solution

0.6 mL

0.6 mL

Other components transfer pipettes, sample tubes, and reagent rack

Sample Information

● Samples must be at room temperature (18-25°C) before beginning test procedure.

● Serum or plasma, either fresh, previously frozen or stored at 2-8°C, may be used in this test.

● Serum or plasma may be stored for up to 7 days at 2-8°C. For longer storage, sample should be frozen (-20°C or colder).

● Previously frozen or older samples must be centrifuged before use.

● Hemolyzed or lypemic samples will not affect results.

● EDTA or heparin in plasma will not affect results.

● Whole blood may be used. Whole blood must be anticoagulated (eg. EDTA, heparin) and may be used either fresh or after refrigeration (2-8°C) for up to one week.

Test procedure

1. Allow components to equilibrate at room temperature (18-25°C) for 30 minutes. DO NOT HEAT.

2. Using the pipet that is provided, transfer 3 drops of sample (whole blood, serum, or plasma) into sample tube.

3. Holding bottle vertical, add 4 drops of conjugate to the sample tube.

4. Cap the sample tube and mix thoroughly by inverting tube 3-5 times.

5. Place the device on a flat surface. Add contents of sample tube to sample well, being careful not to splash contents outside of sample well.

Sample will flow across the result window, reaching the activation circle in approximately 30-60 seconds. Some sample may remain in sample well. Watch carefully for sample or blue color in the activation circle.

6. When color FIRST appears in the activation circle push activator firmly until it is flush with the device body.

Note: Some samples may not flow to the activation circle within 60 seconds, and, therefore, the circle may not turn color. In this case, press the activator after sample has flowed across result window. Keep the device horizontal to ensure accurate results.

7. Read test result at 10 minutes.

NOTE: Positive control may develop sooner, but results are not complete until 10 minutes.

Interpreting Test Result

To determine test results, read the reaction spots in the result window. Any color development in the sample spots indicates the presence of FeLV antigen in the sample. If no color develops in the positive control spot, repeat the test.

Negative Result

Only positive control spot develops color.

Positive Result

Positive control spot and FeLV Ag sample spot develop color.

Reaction With Negative Control

The negative control spot serves as a safeguard against false positives and helps indicate that the assay has been run properly.

Positive Result

If color in the sample spot is darker than negative control spot, result is positive.

Invalid Result

If color in the negative control spot is equal to or darker than sample spot, the test is invalid.

Invalid results

If the sample is allowed to flow past the activation circle, background color may result. Some background color is normal. However, if colored background obscures test result, repeat the test.

No color development
If positive control does not develop color, repeat the test.

Symbol descriptions

IDEXX Technical Support

USA/Canada: 1 800 248 2483 •

Australia: 1300 44 33 99 •


VLN/PCN: 313/5028.03

*SNAP and PetChek are trademarks or registered trademarks of IDEXX Laboratories, Inc. or its affiliates in the United States and/or other countries.

Patent information:

© 2021 IDEXX Laboratories, Inc. All rights reserved.

IDEXX, One IDEXX Drive, Westbrook, Maine 04092 USA


CPN: 1116049.11

Telephone:   207-556-0300
Fax:   207-556-4346
Pet Diagnostics/Order Desk:   800-248-2483
Poultry/Livestock Diagnostics:   800-548-9997
Poultry/Livestock Order Desk:   800-943-3999
THIS SERVICE AND DATA ARE PROVIDED "AS IS". DVMetrics assumes no liability, and each user assumes full risk, responsibility, and liability, related to its use of the DVMetrics service and data. See the Terms of Use for further details.

Copyright © 2023 Animalytix LLC. Updated: 2023-05-29