<a href=showthread.php?s=&postid=769852#post769852 target=_blank>Originally posted</a> by Gary Majchrzak
Steve Colllins, curator of the Indianapolis Zoo-Aquarium in a 1995 issue of 'SeaScope' published results on their findings regarding HLLE and broccoli.
"The occurrence of head and lateral line erosion {HLLE} is a common problem with certain reef fish, particularly tangs and surgeonfish.We experienced an epidemic among our blue tangs {A.coeruleus} population six years ago in our 25,000 gallon reef exhibit here at the Indianapolis Zoo- Aquarium. Other surgeonfish were affected, but angelfish in the exhibit were not.
Water quality was dismissed as a likely cause of the problem." {Goes into a lengthy digression of excellent water quality params and filtration of the 25,000 gallon system.}
Continuing, "In reviewing other possible causes for this malady we next focused on possible dietary deficiancies,because no obvious pathogens were found.Our fish were receiving a varied diet including romaine lettuce and spinach.Initially,we tried elevating the level of vitamin C by incorporating a supplement into a gelatin based food, but this had no effect. We next considered supplementing the level of vitamin A. According to the 'Applied Nutrition and Diet Therapy',page 825, 'One of the most important functions of vitamin A is to maintain the integrity of the epithelial cells...As a result,surfaces of the skin and membranes lining all passages that open to the exterior of the body, as well as glands and ducts are susceptible to disease'.
This was the basis for trying increased amounts of vitamin A after the vitamin C supplement by itself failed to produce results.It was our feeling that the lining of the lateral line ducts had deteriorated.
We were concerned with possible toxicity of high vitamin A levels that has been reported for certain animals. Upon reviewing the nutritional value of different types of lettuce,we found them to be very low in nutrients and began researching the nutritional value of other green vegetables.
Spinach appeared to be higher than lettuce,but it does not hold up well in seawater.Carrots were found to be a good natural food,but they had to be shredded,and were quite messy to feed.
Still, we fed carrots solely for six to eight weeks and observed a resolution of the HLLE. A more complete literature review made broccoli an obvious choice. It is well balanced in many vitamins in addition to the high level of vitamin A, and also has other features that make it acceptable. It holds up very well in the aquarium.Many fish like the flowerettes when they are first added.Only the larger fish could break open the woody layer on the stalks, but once opened small fish feed on the softer pulp material.
We replaced the carrots with broccoli,and we are currently using it in a well-balanced maintenance diet.
After replacing the lettuce diet with first carrots and then fresh broccoli,the HLLE improved to the extent that only a few scars remained on the most severely affected fish.After nearly eight years in the exhibit,most of the original batch of blue tangs are still alive.Broccoli,supplemented with peas and other prepared foods,dominates the diet. No HLLE symptoms are evident in any of the fish in the exhibit."
