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Old 10-13-2006   #28 (permalink)
REC
Nisai
 
Join Date: Jun 2005
Location: Warrenton, VA
Posts: 72
Treating Heron-Inflicted Wounds...

Since we are on the subject of heron strikes, let's talk about treating the wounds that they can inflict because these types of wounds can be a bit extraordinary..

1. Skin scrapes... since the heron typically tries to grap the area behind the head (he does this because the fish does not wiggle there), we will often see the skin scraped and degloved in this area. If the fish is otherwise healthy, these types of wounds will heal by themselves as they are not deep tissue wounds.

2. Tears to the operculum cover area - these are nasty wounds and caused by the heron gripping the fish in the gill area and then losing it. Heron beaks are raspy and can tear skin tissue if the fish gets trapped in them... Typically these are open-wound type sores and need to be treated as such. An in-water anti-biotic, such as nitrofurazone or oxolonic acid, will keep down the pathogenic bacteria counts in the q-tank (don't use these in the pond). Topically treating the wound site can be tricky because of the proximity of the gills and our usual treatments for open wounds such as iodine or PP paste can cause damage to the gills. If you can do injectables, this is a rare time for a prophylactic antibiotic injection. Remember that at this point, the wound was not caused by an existing bacterial infection, such as an ulcer would, so we need to prevent a bacterial infection, not treat one. The protocol is different for this.

3. Puncture wounds to deep tissue but through and through wounds. This wound is caused by the heron striking the fish with its beak and puncturing the surface tissue but does not penetrate into the body cavity itself. Like the wound above to the gill area, we treat this in prevention of a bacterial infection with creating a prisitine environment for the fish to recoup in. Prophylactic anti-biotics are recommended again, using just a single Baytril or similar med injection.

4. Puncture wound to deep tissue but through to the body cavity. Now we have a real problem as the fish's body cavity is exposed to the environment. The first problem we need to solve is to prevent a bacterial infection and this can be done with a good in-water antibiotic, again using nitrofurazone or oxolinc acid. These are reasonably strong, broad-spectrum antibitoics that work well on the pathogenic bacteria we see in these situations.. they also kill filters so you have another problem in managing water quality. But the real problem is the loss of electrolytes as the fish is literally leaking its body fluids out of its body. And because the body is in trauma, it tends to leak more. To combat this, we look to a human trauma medicine technique and we create an electrolyte bath for the fish in the q-tank. This bath consists of sodium chloride, calcium chloride, and potassium chloride mixed in a 70/20/10% ratio respectively. This is one of rare occassions that I recommend sustained exposure to high chloride levels but you have no choice. What you are looking for is a "salt" (actually chloride) level of .6 to .8% to start and then moving higher if the fish does not respond. Calculate the volume of "salt" that you would need given to reach these levels in the volume of water in your q-tank and then using the 70/20/10 ratio, add that amount of sodium, calcium and potassium chloride to the water. Your "salt" meter or test kit (which measures chloride content) will give you an accurate enough reading. This combination of chlorides will help the fish recover and prevent a physiological breakdown of the organs.

5. Now the bad one.... blunt force trauma... this is the one problem we can little about. Since the heron strikes the head area, we often see a fish literally paralyzed by the strike. Yes, fish can concuss in the same way we do by a blunt force strike to the head. Every catfish fisherman knows the best way to dispatch a big cat is with a ball bat to the head. But even worse than a concussion, is damage to the spine and nervous system. I have seen the results of a heron strike on the "neck" region of the fish that separated the spinal column from the skull. If you suspect this, then euthanizing the fish is your only recourse. Although, not many fish will survive this kind of damage for very long with many just drowning.

However, if your fish has survived a blunt force attack to the head region, it can be treated. As with all q-tank trauma procedures, we start with salting the q-tank to .3 for starters and raising the temps to 78 deg F (optimal immune system temps). Chances are that your fish is in "shock" and is sitting on the bottom very quietly or laying on its side. One of the tricks to diagnosing neurological problems in fish is is to hold it level in the water and look at its eyes from straight ahead.. so you can see the position of both eyes...they should be level. Now, tilt the fish one way and then the other and watch the position of the eyes. In a healthy fish, the eyes will stay level.. in a fish with a neurological problem, the eyes will "tilt" with the body position. We can use this trick to adjudge how close a fish is to death as well.

In blunt force trauma cases, we will also see muscular disorders, such as spasms and curling. If the fish is otherwise breathing fine, you might want to try a single shot of dexamethasone, a corto-steroid. This can help relax the fish's muscles. The warm water and salt will help as well.

Keep in mind that all of these treatments are done in a q-tank where the water can be managed easily. Unlike ulcers, we typically have multiple problems to deal with from a heron strike, so look at all of the possibilities and exclude them as you go along.

REC
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