Ocular tissue changes associated with anterior segment opacity in lumpfish (Cyclopterus lumpus L) eye

Abstract

Lumpfish use their vision to hunt prey or, in the case of aquaculture, to see and eat pelleted diets. A common anterior ocular opacity abnormality designated in the literature as “cataract” described in both farmed and wild lumpfish has not yet been characterized in detail at the pathobiological level. We describe here lens tissue changes associated with cataract in cultured and domesticated lumpfish. Methodology included gross observations, ophthalmoscopy and histology. Young adult cultured animals approaching 400 days post‐hatch presented a range of anterior segment opacities associated with lenticular abnormalities observable at a histological level. Wild aged domesticated animals also displayed cataracts characterized mainly by abnormalities of the lens observed by both ophthalmoscopy and histology. Dysplastic lesions of the lens in one aged domesticated lumpfish were accompanied with both retinal and optic nerve degeneration. These novel naturally occurring anatomical changes in lumpfish present both commonalities and unique features associated with cataract in young adult cultured animals versus aged domesticated broodstock animals.

The role of dietary vitamin A in mechanisms of cataract development in the teleost lumpfish (Cyclopterus lumpus L)

“…All animal experimentation was approved by Memorial University's Institutional Animal Care Committee (RG‐17‐03) and followed the Canadian Council on Animal Care guidelines, as previously described (Ahmad et al., 2019; Paradis et al., 2019). Eggs from cultured domesticated Newfoundland brood stock lumpfish were fertilized and cultured at the Dr. Joe Brown Aquatic Research Building.…”

“…Cyclopterus lumpus L, commonly known as the lumpfish, is a North Atlantic Ocean teleost fish that can tolerate a range of habitat conditions (Mortensen et al., 2020; Nytrø et al., 2014). Lumpfish are visually guided animals and rely on a healthy visual system to survive (Ahmad et al., 2019; Jonassen et al., 2017; Paradis et al., 2019). Lumpfish have proven to be beneficial for the salmon farming industry as a biological delouser since they graze and feed on sea lice, thereby protecting salmon populations from lice infestation (Imsland et al., 2014; Johansen et al., 2011).…”

“…Despite the high prevalence of cataract in lumpfish (Jonassen et al., 2017), the mechanisms of cataractogenesis are poorly understood in this species. Our group has previously characterized lumpfish cataract and the specific morphological tissue changes that occur (Paradis et al., 2019). However, further investigation is required to better understand the pathways involved in these tissue changes and ultimately lens opacification.…”

Cleaner fish in aquaculture: review on diseases and vaccination

“…The disorder leads to formation of opacities within the eye lens (Fig. 28), which causes disturbances in the dispersion of light passing through, resulting in reduced sight or, ultimately, blindness of affected fish (Paradis et al, 2019). As lumpfish rely on sight to feed, this condition could negatively affect their efficiency as sea lice cleaners (Scholz et al, 2018a; Paradis et al, 2019).…”

“…28), which causes disturbances in the dispersion of light passing through, resulting in reduced sight or, ultimately, blindness of affected fish (Paradis et al, 2019). As lumpfish rely on sight to feed, this condition could negatively affect their efficiency as sea lice cleaners (Scholz et al, 2018a; Paradis et al, 2019). Cataract has been linked to nutritional deficiencies in other fish species (Waagbo et al, 2003; Williams, 2006; Schmidt‐Posthaus & Marcos‐López, 2014).…”