Published on Dec. 19, 2019

Counting eggs

Troutlodge U.S. egg shipments are electronically counted with extremely high accuracy, and generally include an agreed “overage” which is typically 3%. Troutlodge are very careful about counting the number of eggs supplied in each shipment.

Some customers’ internal policies require them to make their own count on arrival to confirm they have received numbers listed on the packing list.

Best hatch rates are achieved by rehydrating, disinfecting if necessary and placing eggs directly into incubation as quickly as possible upon arrival.

Given that, there are a variety of ways to count eggs as outlined below. Whichever system is used for counting eggs it is recommended that several samples are taken to ensure an accurate count.

Von Bayer trough method

This is recommended as it is quick, simple and accurate and utilizes a trout egg measuring trough, easily made but also available from Troutlodge on request.

The trough measures 30.5cm (12") length (inside dimension), with a 45º bend and a depth of approximately 3.5cm (1.4").


There are two steps in using the Von Bayer method

  • First sizing the eggs
  • Then counting the eggs


Sizing the eggs:

  1. Eggs during transit can become dehydrated and slightly smaller in size so it is important to rehydrate the eggs in flowing water.
  2. Fill your Von Bayer trough with a single row of eggs.
  3. Use a non-sharp pointed object (pencil) to discard extra eggs from the trough. Do not force the eggs into the trough. The eggs should fit side-by-side, just touching, but there should not be any spaces.
  4. Count the number of eggs that fill the trough.
  5. Refer to the Von Bayer chart, at the end of this guide, to determine the size of the eggs (eggs per litre or liquid ounce).
57 eggs_2.png
Place eggs touching side by side in the trough and then count eggs

Counting the eggs

  1. Take a 1 litre (or 1 quart if using fluid ounces.) plastic measuring cup or jug. If necessary, cut off any portion of the cup that is over the 1 litre or 1 quart mark. This will make it faster and easier to level the measured eggs.
  2. Fill the measuring cup at least half full of water.
  3. Use a strainer (plastic rice colander works well) and add eggs to the cup. Tap the side of the cup to get rid of air bubbles and to settle the eggs. The eggs will displace the water in the cup.
  4. Level eggs at the top of the cup by gently scraping off excess eggs.
  5. Pour measured eggs into separate container.
  6. Repeat until all eggs have been measured / counted.
  7. Multiply number of litres (or quarts) by the number of eggs per litre (or quart) as per the Von Bayer chart. This will give you the total number of eggs.
eggs per litre.jpg
Measure and count all the litres in the shipment and multiply by number per litre for total eggs.

Electronic egg counters

Electronic egg counters are available from specialist suppliers but are expensive and are usually only considered by the largest hatcheries needing to count large volumes of eggs. Electronic egg counters can count more than 200.000 eggs per hour with a 99% accuracy level.

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Von Bayer Chart for the estimation of the number of eggs

Number of Eggs per 12" Trough Diameter of Eggs (Inches) Diameter of Eggs (mm) Number of Eggs per Liquid Quart Number of Eggs per Liter ~Number of Eggs per Liquid Ounce
35 0.343 8.712 1,677 1,772 52
36 0.333 8.458 1,833 1,937 57
37 0.324 8.230 1,990 2,103 62
38 0.316 8.026 2,145 2,267 67
39 0.308 7.823 2,316 2,448 72
40 0.300 7.620 2,606 2,754 81
41 0.292 7.417 2,690 2,843 84
42 0.286 7.264 2,893 3,057 90
43 0.279 7.087 3,116 3,293 97
44 0.273 6.934 3,326 3,515 104
45 0.267 6.782 3,556 3,758 111
46 0.261 6.629 3,806 4,022 119
47 0.255 6.477 4,081 4,313 128
48 0.250 6.350 4,331 4,577 135
49 0.245 6.223 4,603 4,864 144
50 0.240 6.096 4,895 5,173 153
51 0.235 5.969 5,214 5,510 163
52 0.231 5.867 5,490 5,802 172
53 0.226 5.740 5,862 6,195 183
54 0.222 5.639 6,185 6,536 193
55 0.218 5.537 6,531 6,902 204
56 0.214 5.436 6,905 7,297 216
57 0.211 5.359 7,204 7,613 225
58 0.207 5.258 7,630 8,063 238
59 0.203 5.156 8,089 8,548 253
60 0.200 5.080 8,459 8,939 264
61 0.197 5.004 8,851 9,354 277
62 0.194 4.928 9,268 9,794 290
63 0.191 4.851 9,712 10,264 304
64 0.188 4.775 10,184 10,762 318
65 0.185 4.699 10,638 11,242 332
66 0.182 4.623 11,225 11,863 351
67 0.179 4.547 11,799 12,469 369
68 0.177 4.496 12,203 12,896 381
69 0.174 4.420 12,846 13,574 401
70 0.171 4.343 13,533 14,302 423
71 0.169 4.293 14,020 14,816 438
72 0.167 4.242 14,529 15,354 454
73 0.164 4.166 15,341 16,212 479
74 0.162 4.115 15,916 16,820 497
75 0.160 4.064 16,621 17,565 519
76 0.158 4.013 17,157 18,132 536
77 0.156 3.962 17,825 18,837 557
78 0.154 3.912 18,528 19,580 579
79 0.152 3.861 19,270 20,365 602

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