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Adelbert De Clercq

Doctor of Philosophy
Study Completed: 2018
College of Sciences


Thesis Title
The effect of incubation temperature on early malformation, regionalisation and meristic characters of the vertebral column in farmed Chinook salmon (Oncorhynchus tshawytscha)

Read article at Massey Research Online: MRO icon

Skeletal deformities are a recurrent problem in salmon farming and have production limiting and animal welfare impacts. Vertebral column deformities are recognised and well-studied in juvenile and adult stages. Malformations that occur in early life stages are less known. Elevated incubation temperature is a risk factor for skeletal anomalies. Mr De Clercq devised a temperature experiment where animals were raised from fertilised eggs to first feed stage at a constant 4°C, 8°C and 12°C. Characterisation of the vertebral body units and subdivision into regions was revisited. Salmon raised at 8°C and 12°C were transferred to sea cages and followed. Skeletal malformations were found in post-hatch stages of salmon in each temperature group, even in externally normal looking animals. Temperature had a significant effect on the number of vertebrae in a single region. This study found that early freshwater incubation temperature could influence the occurrence of deformities in seawater stages.

Dr Matthew Perrott
Professor Ann Huysseune
Professor Peter Davie
Professor Eckhard Witten