Your video will begin in 40

Hi Friends... welcome to part 2 of our new series FISH BREEDING AND MANAGEMENT. This video is self explanatory and all information will be gotten upon...

Дата загрузки:2021-09-15T20:00:13+0000

Hi Friends... welcome to part 2 of our new series FISH BREEDING AND MANAGEMENT.

This video is self explanatory and all information will be gotten upon watching this video to the end.

If you have not seen the Part One please search and watch as this will lead you to a better understanding.

Subscribe is you are new and watch over 400 videos on this channel (FISH ACADEMY) drop your questions as you will get help from me or any member of this channel.

Remember to LIKE AND TO SHARE because sharing is caring.



By Brian C. Small and published by the Southern Regional Agricultural Center and the Texas Aquaculture Extension Service - Managing egg diseases and improving hatch rates in channel catfish hatcheries requires good husbandry and continuous attention to detail. The optimal health of developing embryos is best ensured with healthy broodfish, a good environment, limited handling, and isolation from pathogens.

Prevention should be considered the first line of defense when managing egg disease and survival. Simple management strategies, such as disinfecting the hatchery before the hatchery season, having separate nets and equipment for each hatching trough, disinfecting hands, disinfecting egg masses before bringing them into the hatchery, and using a pathogen-free water supply, help prevent the introduction of infectious pathogens into the hatchery. The goals of a good hatchery management program should be to prevent disease and provide the optimal environment for embryo development and survival. Specific information on hatchery management and water quality can be found in the SRAC publications listed at the end of this publication. The focus here is on improving hatch rates and managing common egg diseases.

Understanding catfish embryo development

The most productive method of producing catfish fingerlings is to transfer eggs to a hatchery after spawning (Fig. 1). The management techniques discussed in this publication focus on production systems with dedicated hatcheries for incubating eggs. In these systems, spawning containers (Fig. 2) are often checked every day to every 3 days, so that eggs are collected at various stages of development. The age or developmental stage of the embryo can be a significant factor in managing for disease. Stress can be more harmful at early developmental stages and can result in poor survival. Understanding the progression of development is important for improving hatch rates, and estimating the age of catfish eggs helps when planning chemical treatments.

The time it takes for catfish eggs to hatch depends on water temperature. Channel catfish typically spawn in the spring, when water temperatures are between 70 and 84 °F (21 and 29 °C). At these temperatures, the time from spawn to hatch is 5 to 10 days (Fig. 3). The exact time of spawning usually is not known, so the age of eggs must be estimated visually. Figure 4 illustrates how to estimate egg age at 78 F (26 C) based on visual observations of embryo development. You will need to adjust for temperature using the relationship in Figure 3 as a reference.

Preventing egg death

The factors that can cause dead eggs (eggs that have stopped developing) include excessive handling, overcrowding, high temperature, water hardness, and transport delays. Important hatchery water quality parameters are reviewed in SRAC Publication No. 461, and degassing is reviewed in SRAC Publication No. 191.

Excessive handling
Embryos in the early development stages are sensitive to handling and should be handled as little as possible to prevent mechanical injury.
Be the first to comment