1. Introduction
This manual provides comprehensive instructions for the safe and effective use of the GOYOJO Ovulation Tester, Model B0BWMTLWSN. This device is designed to assist breeders in identifying the optimal breeding time for cattle and horses by detecting changes in vaginal mucus electrical resistance, which correlates with the ovulation cycle.
Please read this manual thoroughly before operating the device to ensure proper usage and to achieve accurate results.
2. Safety Information
- Always handle the device with clean hands to prevent contamination.
- Do not immerse the main unit in water or other liquids. The probe is designed for contact with mucus, but the electronic components are not waterproof.
- Keep the device out of reach of children and animals when not in use.
- Use only the specified battery type. Ensure correct polarity during battery installation.
- If the device is damaged, do not attempt to repair it yourself. Contact customer support for assistance.
- Dispose of batteries and the device according to local environmental regulations.
3. Product Overview
The GOYOJO Ovulation Tester consists of a main unit with a digital display and a long probe designed for insertion. The device measures the electrical resistance of vaginal mucus to indicate the stage of the estrous cycle.

Figure 3.1: GOYOJO Ovulation Tester with digital display and probe. The image illustrates the device's main components and its application for different animals, including pigs, sheep, cattle, horses, and dogs.
3.1 Components
- Main Unit: Contains the electronic circuitry, digital display, and control buttons.
- Probe: The elongated part inserted into the animal, equipped with electrodes for measurement.
- Display Screen: Shows numerical readings of electrical resistance.
- Handle: Ergonomically designed for comfortable grip during use.
4. Setup
4.1 Battery Installation
- Locate the battery compartment cover, usually at the base of the handle.
- Open the cover by sliding or unscrewing it.
- Insert the required batteries (e.g., 9V battery or AA batteries, refer to device markings) ensuring correct polarity (+/-).
- Close the battery compartment cover securely.
4.2 Initial Check
After installing batteries, press the power button (if available) to turn on the device. The display should illuminate and show a reading, typically "0" or a low number, indicating it is ready for use.
5. Operating Instructions
5.1 Preparation
- Ensure the animal is calm and restrained appropriately for safety.
- Clean the probe thoroughly with a disinfectant solution (e.g., mild antiseptic) and rinse with clean water. Dry the probe completely before use.
- For optimal results, ensure the animal's vulva area is clean.
5.2 Taking a Measurement
- Gently insert the clean, dry probe into the animal's vagina. The depth of insertion should be sufficient to ensure the electrodes are in contact with the vaginal mucus.
- Rotate the probe slowly 360 degrees to ensure good contact with the vaginal wall and mucus.
- Press the measurement button (if applicable) or wait for the automatic reading to appear on the digital display.
- Record the reading. It is recommended to take 2-3 readings and calculate the average for better accuracy.
- Withdraw the probe gently.

Figure 5.1: Side view of the GOYOJO Ovulation Tester, illustrating the length of the probe and the main unit's design for handling during operation.
5.3 Interpreting Results
Ovulation is typically indicated by a significant change (usually a drop, then a rise) in the electrical resistance readings over a period of days. Consistent daily measurements are crucial for accurate interpretation.
- Low Readings: Generally indicate a period away from ovulation.
- Rising Readings: Suggest the animal is approaching estrus.
- Peak Readings (or specific patterns): Indicate the optimal time for breeding. Consult veterinary resources or experienced breeders for specific resistance value ranges for cattle and horses, as these can vary.
It is advisable to establish a baseline for each animal by taking readings over several cycles if possible.
6. Maintenance
6.1 Cleaning
- After each use, clean the probe thoroughly with a mild disinfectant and rinse with clean water.
- Wipe the main unit with a soft, damp cloth. Do not use abrasive cleaners or immerse the main unit.
- Ensure all parts are completely dry before storage.
6.2 Storage
- Store the device in a clean, dry place, away from direct sunlight and extreme temperatures.
- If storing for an extended period, remove the batteries to prevent leakage and damage to the device.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not turn on. | Dead or incorrectly installed batteries. | Replace batteries with new ones, ensuring correct polarity. |
| Inconsistent readings. | Insufficient contact with mucus, dirty probe, or animal movement. | Ensure probe is clean and dry. Re-insert and rotate slowly. Take multiple readings and average. Ensure animal is calm. |
| Display shows error message. | Device malfunction or extreme environmental conditions. | Turn off and restart the device. If error persists, contact customer support. |
8. Specifications
- Brand: GOYOJO
- Model: B0BWMTLWSN
- Application: Ovulation detection in cattle and horses (also suitable for dogs, pigs, cats, canine as per product description, but primary focus for this model is cattle and horse).
- Power Source: (Not specified in input, assuming standard batteries like 9V or AA)
- Display: Digital
- Measurement Principle: Electrical resistance of vaginal mucus
- Date First Available: February 20, 2025
9. Warranty and Support
GOYOJO offers a 30-day satisfaction guarantee. If you encounter any quality concerns with your GOYOJO Ovulation Tester within 30 days of purchase, please contact our customer support for assistance. We are committed to resolving issues through replacements or refunds.
For technical support or warranty claims, please refer to the contact information provided with your purchase or visit the official GOYOJO website.


