Canine and feline early – pregnancy test kit

A canine and feline early – pregnancy test kit is a tool used to detect whether a dog or a cat is pregnant.

I. Detection Principle

1. Based on Hormone Detection Principle
   • Most canine and feline early – pregnancy test kits determine pregnancy by detecting pregnancy – related hormones in female dogs or cats. Among them, relaxin is the most commonly detected hormone.
   • After a dog or a cat becomes pregnant, the placenta begins to secrete relaxin. Relaxin enters the bloodstream, and by detecting the level of relaxin in samples such as blood and urine, it is possible to infer whether the dog or cat is pregnant.
   • The reagents in the test kit usually contain antibodies that can specifically bind to relaxin. When relaxin is present in the sample, it will react with the antibodies, and then the test result will be displayed through color – developing reactions, fluorescence reactions, etc.
2. Immunochromatography Technology
   • Many early – pregnancy test kits use immunochromatography technology. Generally, there is a test strip in the kit, which has structures such as a sample pad, a conjugate pad, a nitrocellulose membrane, and an absorbent pad.
   • After the sample (such as urine) is dropped onto the sample pad, it moves towards the other end due to capillary action. If there is relaxin in the sample, it will first bind with the anti – relaxin antibody labeled with a marker (such as colloidal gold) on the conjugate pad to form a complex.
   • The complex continues to move. When it moves to the test line (T – line) on the nitrocellulose membrane, if another anti – relaxin antibody pre – coated on the T – line can capture the complex, a color – developing reaction (such as the appearance of a red band) will occur at the T – line. At the same time, regardless of whether there is relaxin in the sample, other components of the sample will cause the marker to move to the control zone (C – line) and bind with the anti – marker antibody pre – coated on the C – line to form a color – developing reaction (such as the appearance of a red band). The color development of the C – line is used to determine whether the test strip is valid.

II. Kit Components

1. Test Strip or Test Card
   • It is the core component of the test. Its internal structure is as described above and is used to achieve sample chromatography and detection reactions.
2. Sample Collection Tools
   • For urine testing, a urine collection cup may be provided; for blood testing, there will be blood – collection needles, blood – collection tubes, etc.
3. Sample Diluent (May Have)
   • When the sample concentration is too high and may affect the test result, it is used to dilute the sample. For example, if a blood sample is too thick, it may need to be appropriately diluted with a diluent.
4. Positive and Negative Controls
   • The positive control is a sample containing known relaxin and is used to verify the effectiveness of the kit in detecting pregnant samples. The negative control is a sample without relaxin and is used to exclude false – positive results and ensure the reliability of the test.

III. Detection Steps

1. Sample Collection
   • Urine Sample Collection: For dogs and cats, urine can generally be collected with a clean container when they urinate, or it can be collected during the first urination in the morning because the hormone levels in the urine are relatively stable at this time. Pay attention to avoiding contamination when collecting urine.
   • Blood Sample Collection: Professional operation is required. Use a blood – collection needle to draw blood from the vein of the dog or cat (such as the front – limb vein). After collecting an appropriate amount of blood, put it into a blood – collection tube.
2. Sample Treatment (If Necessary)
   • As mentioned earlier, if the blood sample concentration is too high, it needs to be diluted with the sample diluent according to the requirements of the kit instructions.
3. Sample Loading
   • Drop the collected or processed sample onto the sample pad of the test strip or test card. If it is a urine sample, generally drop a certain number of drops (such as 3 – 5 drops) as specified; if it is a blood sample, a specific method may be required, such as first dropping the blood onto a specific area and then adding the diluent, etc.
4. Waiting for Results
   • After sample loading, wait for a certain period of time to observe the results. The waiting time may vary for different kits, generally about 5 – 15 minutes.

IV. Result Judgment

1. Positive Result
   • If both the test line (T – line) and the control zone (C – line) of the test strip or test card show color development (such as red bands), it indicates a positive test result, meaning that the dog or cat may be pregnant.
2. Negative Result
   • When there is no color development on the test line (T – line) but there is color development on the control zone (C – line), it indicates a negative test result, that is, the dog or cat is not pregnant.
3. Invalid Result
   • If there is no color development on the control zone (C – line), regardless of whether the test line (T – line) shows color development, this test result is invalid and re – testing is required.

V. Application Significance

1. Pet – Raising Management
   • For pet owners, being able to know in a timely manner whether their dogs or cats are pregnant helps to make corresponding feeding preparations in advance. For example, pregnant dogs and cats need to adjust their diet structure, increase nutrient intake, and be provided with a quieter and more comfortable living environment.
2. Veterinary Clinical Diagnosis
   • In veterinary clinical practice, accurately determining whether a dog or cat is pregnant is very important for subsequent medical decisions. If a dog or cat is pregnant, the impact on the fetus needs to be considered when treating diseases, administering drugs, performing X – ray examinations, etc., to avoid fetal damage.