Receiving & Counting Eggs
Receipt of EggsOnce the eggs arrive at your farm, it is important that you first take note of the condition of the packaging and the eggs, as well as take an accurate count of the eggs received. In addition, make sure to take accurate measurements of your hatchery conditions, including water temperature and oxygen saturation. Taking note of all of this information is not only important for your own record keeping and for later steps in the hatching process, but it also better enables Troutlodge to diagnose the cause of any problems in the rare case that you experience problems in the hatch-out of the eggs.
Opening the Box
Customers should take great care in opening each box of eggs. For complete step-by-step instructions, including photos, on how to properly open Troutlodge boxes, please see the link in the Relevant Info box to the right.
Tempering the Eggs
Once you have opened the box and are ready to introduce them into your hatchery water, it is critical that you temper the eggs into your water. Tempering means to gradually bring the temperature of the eggs up to match the incubation temperature of your hatchery. The eggs will arrive on ice at a temperature of +/- 4°C (39.2°F), and it is recommended that you increase the temperature of the eggs as slowly as 2°C each hour. Various methods can be used for this process. For more information on various tempering methods, please see the link in the Relevant Info box to the right.
Because a good start is critical to the long-term growth and survivability of the fish and because fish are most susceptible to disease and mishandling during the early-rearing stages, it is imperative that you utilize your best water in your hatchery system. Ideally, hatchery systems should be flow-thru and utilize cold, pathogen-free water. The ideal hatching temperature for Rainbow trout is 8 - 12°C (~46 - 54°F), though temperatures ranging from 4 - 18°C (~39 - 64°F) are ok if proper precautions are taken. A strict bio-security program should be in place in the hatchery to limit the possible introduction of disease. At a minimum, this program should include a disinfectant footbath and hand-wash, and all equipment should be reserved exclusively for hatchery use.
All eggs shipped from Troutlodge have been disinfected in a solution of 100 ppm Iodine at the time of hardening and before placing the eggs in the hatchery for incubation, and then again just prior to packaging. However, many farmers either choose to or are required by law to disinfect the eggs again upon arrival into their hatcheries. For more information on recommended treatment products and levels, please see the SRAC bulletin "Handling Eggs and Fry" in the Relevant info section to the right.
It is critical to note that eggs should not be disinfected within five (5) days of hatching, as this can cause excessive mortality and/or premature hatch. Eggs are shipped from Troutlodge at 245 TCU, meaning they will arrive with ~65 TCU (6.5 days at 10°C) remaining before hatch. If you have any questions about when the eggs are expected to hatch, please contact Troutlodge before disinfecting.
Once the eggs have successfully been tempered, and thereby re-hydrated, you can proceed with counting them. Various methods can be used for counting eggs. Troutlodge utilizes the Von Bayer method when counting and packaging eggs, as this method has proven to be very simple and accurate. Other methods include volumetric displacement, weight, or use of an electric egg counter. Regardless of the method used, be sure to repeat the process three to five times to ensure an accurate count.