Ultrasound

Two veterinarians evaluate a Chinook captive brood fish anesthetized with MS-222 by ultrasound to determine sex; this fish is a female. Photo: Kari Neumeyer, Northwest Indian Fisheries Commission

Broodstock Injections

A hatchery staff member holding a captive brood Chinook in the proper head-down position for intracoelomic injection behind the pelvic girdle. One improvement in the position shown would be to leave the fish’s head and gills submerged under the water.
Hatchery staff members have two totes set up, one for anesthesia with buffered MS-222 and the other with fresh water for recovery, for non-lethal spawning of steelhead. Fish are anesthetized in the tote with buffered MS-222, then removed and manually stripped aided with sodium bicarbonate flushes, recovered in the freshwater tote, and finally returned to the broodstock holding pond pictured behind the totes.

Gamete Collection

A hatchery staff member holding the type of colander commonly used for egg collection. Some hatcheries prefer to use colanders to drain off the extra ovarian fluid. Other facilities prefer to collect eggs into small buckets so that the ovarian fluid is retained.
Hatchery staff use a pneumatic captive bolt gun to euthanize coho salmon broodstock. From our experiences with this technique, having a solid base to place the fish on is very important for this method to work properly; in this case hatchery staff constructed the special table pictured here.
Milt from a male spring Chinook salmon is manually stripped into a bucket full of eggs. This is the first step of the fertilization process. Photo: Vannesa Ortiz.
Eggs from the 328th spring Chinook female spawned that season in a bucket with milt added. Bubbles are normal and a strong sign that the milt has activated and is fertilizing the eggs. Photo: Vannesa Ortiz.
A large cooler with insulation added inside on the bottom to protect the milt (stored in ziplock bags injected with oxygen and labeled with the identification number of the male that it was collected from) from direct contact with the ice packs (not pictured, but below the insulation).

Incubation

A half stack of Heath trays; the eggs from two Chinook females (the first two fish spawned 09/07/2017) were combined into the top tray. They are water hardening in a buffered iodophor solution. When water hardening and surface disinfection is complete, the tray will be pushed into the stack and the water flow will be turned on, flushing out the disinfectant.
 Heath tray incubation set up at a hatchery. The headbox is the large, aluminum box running on the ceiling above the stacks. The headbox supplies water to each stack of heath trays; for this setup, the trays are plumbed as half stacks, which means that the top and bottom half of each column has a separate source of water flow. The white structure running parallel along the top of the headbox is protecting the chemical-grade pump tubing that delivers treatments (usually formalin) to the incubating eggs via peristaltic pump.
Nopad incubators used to incubate millions of coho salmon eggs at a tribal salmon enhancement hatchery. Photo: Myron Kebus.

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Nora Hickey, D.V.M.

Nora is a fish veterinarian based in Washington State with a lifelong passion for fishkeeping. She began at age three with her first zebrafish aquarium. After volunteering at the New England Aquarium during her time at MIT, she earned her veterinary degree and now combines her love for fish and medicine. Nora has a special interest in Corydoradinae catfish and keeps several aquariums at home.