Fish Size Correlates to Size and Morphology of Intermuscular Bones in Tambaqui Colossoma macropomum as Shown by Dissection and X-ray Imaging Methods

One of the main issues in the processing sector of the tambaqui Colossoma macropomum is the removal and/or fragmentation of intermuscular bones (IBs), which negatively impacts its production chain. In this sense, we quantitatively examined the IB variation in farmed tambaqui (n = 127) by comparing the direct anatomical dissection with the high-resolution X-ray imaging method. The number of IBs from the anatomical dissection on the left side of the fish (27.3 +/- 5.70 bones) was comparable to that of X-ray analysis (26.9 +/- 6.03 bones) (p > 0.05). In addition, 76% of deviation in IB number between the two studied methods was one to three, indicating both methods are equally efficient for identifying and quantifying IBs. We found a strong positive correlation (R = 0.8, p < 0.001) between the X-ray and the dissection methods. Our predictive models indicated that more than 50% of variation in IB length can be explained by growth parameters. Our results demonstrated that the X-ray method can provide accurate phenotypic data (in vivo) for IB counting and length measurements by extrapolating from the standard length, body weight and trunk over axis area of tambaqui.

Automated summary

The high-resolution X-ray imaging method is effective for analyzing the quantity of intermuscular bones in tambaqui fish, providing accurate phenotypic data.