These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Effects of Hatchery Rearing Density, Handling, and Nutrition on Renibacterium salmoninarum Infection Prevalence in Juvenile Chinook Salmon.
    Author: Larson DL, Faisal M, Tempelman RJ, Yu H, Scribner KT.
    Journal: J Aquat Anim Health; 2020 Sep; 32(3):116-126. PubMed ID: 32298497.
    Abstract:
    Bacterial kidney disease, caused by Renibacterium salmoninarum (RS), is a chronic and often fatal disease of salmonid species, and can be particularly harmful to hatchery-reared Chinook Salmon Oncorhynchus tshawytscha. A considerable amount of research has focused on the prevention of vertical and horizontal transmission; however, a comparatively little amount has investigated factors that increase the prevalence of RS infection in captive environments. We evaluated the effects of three common hatchery conditions (handling, nutrition level, and rearing density) on RS infection prevalence. Fish were sampled at 30-d and 60-d postexposure to RS. Of 577 juveniles examined, 65 (11.27%) had anterior kidneys infected with RS. Using a logistic mixed model analysis, we found effects of nutrition level (P = 0.018), handling (P = 0.010), and sampling period (P = 0.003) on the prevalence of RS. The interactions of nutrition and handling (P = 0.008) and nutrition and time (P < 0.001) were also significant. When fed a standard-nutrition diet, proportionately fewer fish were infected with RS when not handled (7.16% versus 0.04%; P = 0.003). Fish in the standard-nutrition group also had a lower prevalence of RS during the second sampling period (4.08% versus 0.08%, respectively; P < 0.001). When not handled, rearing with standard nutrition (11.50% versus 0.04%; P = 0.004) resulted in a reduction in prevalence of RS infection. Additionally, nonhandled fish had a much lower prevalence of RS infection during the second sampling period (2.66% versus 0.21%; P = 0.009). While density did not affect the prevalence of RS infection (P = 0.145), fish reared at a higher density had lower RS infection when not handled (16.48% versus 0.84%, P = 0.004). For fish at a higher density, the RS prevalence was lower during the second sampling period (10.57% versus 1.40%; P = 0.002). Our results suggest that hatchery managers can reduce RS infection prevalence by maintaining an adequate nutritional regime as recommended by the manufacturer. Additionally, the prevalence of RS may be reduced if managers decrease handling of hatchery-reared Chinook Salmon if exposed to RS.
    [Abstract] [Full Text] [Related] [New Search]