Signs Your Fish Might Be Sick. The major breakthrough that can work towards effective treatment of fish diseases ensuring that the first evidence of diseases in fish identified thereby leading to an accurate diagnosis. In case a health issue occurs, the ill fishes will reflect various changes in their behaviour, feeding pattern, and overall body status. The consolation that, regardless of which of the >40 000 species of fish that can encountered in practice, the clinical manifestations do remain very alike. However, the bad news is that, clinical signs exhibited are usually non-specific and cannot just lead to a diagnosis.
A few of such behavioural changes give the viewer some clues. Among one of the first signs of disease is inappetance. The causes of inappetance might be poor environment (e.g water is too hot or cold), a variety of infectious diseases and so on. Piping fish will most likely be experiencing oxygen shortage or carbon dioxide poisoning (Loh and Landos, 2011; Loh, 2014). This could either be due to alteration in dissolved gases, or is the case where there is compromisation to their respiratory system (e.g. parasitic infections of the gills, nitrite toxicosis and acidic water).
Anchor worms
Respiratory rate and effort would also increased in these affected fish. Scraping fish (fish flash) are responding to skin irritation that may accompany parasitic infections (Wildgoose, 2001; Loh and Landos, 2011) including fish lice (Argulus) and skin flukes (Gyrodactylus spp.) as well as the panoply of various protozoa (e.g. white spot disease). On top of this, all the agents do make fish hold their fins in a clamped position (Loh and Landos, 2011; Loh and Landos, 2014). In some cases, we can have the obvious pathogens. The only conditions that gross findings are pathognomonic to the condition.
May be fish lice (Argulus) and anchor worm (Lernaea) and white spot disease (Figure 2). Nevertheless, lymphocystis affected fish (Figure 2) may easily mistaken with Ichthyophthirius. As a matter of fact, most cases brought to the veterinarian are more difficult. In stressful situations discus fish become solid dark, fashionable fish such as oscar becomes pale and other such as koi get spread out skin congestion. Too much mucus (or slime) contrasts effectively with the body of the darkly.
Body flukes
Pigmented fish, and it is convenient, therefore, to consider black fish. Remember that such abundance of slime can better noticed when fish are in standing water. Such slime frequently created in reaction to irritation of the skin, including that caused by various ectoparasitic diseases and improper water conditions (e.g. low pH). Fish may affected with tumours that must distinguished with neoplasia as well as inflammations and cystic bodies (e.g. parasitic cysts). Ulcers may also develop that may be broad and deep thereby exposing the muscle and even bone.
Fish ulcers not necessarily caused by on primary bacterial infection. In more than half the cases the inciting cause is parasitic (e.g. because of infestation with skin fluke). Ulcerated fish usually gets dermato-septicaemia and it will be important to work on it by offering cure on the main cause. Hobbyists commonly refer to bacterial septicaemia leading to ascites, protrusion of scales and exophthalmia as dropsy and pop-eye. Although this might hold in certain situations, this is not always the case. Actually, dropsy is not a specific indication of excess fluid build-up as a result of a collapse.
Clamped fin
In the mechanisms of fluid polarity (or osmoregulation). Dropsy does not only develop in fish with bacterial infections and not every disease to diagnosed as dropsy is an infection of bacteria (Loh and Landos, 2011; Loh, 2014). This fluid accumulation can be as a result of a number of reasons such as inability to exclude water, inability to get rid of fluid or excessive production of fluid. In order to keep the matter a little simple, we can state that the fish can balance their fluid by appropriately working skin/mucus barrier, gills, kidneys and cardiovascular system. In case of any of these systems being abnormal.
(e.g. skin ulcers due to fungal infections in barramundi, bacterial gill disease in guppy, kidney cysts in goldfish, ovarian cancers in the koi) then fish may develop fluid accumulation (Loh and Landos, 2011; Loh, 2014). On the other hand, fish may appear thin. Malnourished fish have swollen heads in their disproportionate size as well as with long and slim bodies. These fish are denominated as pin heads in the salmonid industry (Loh and Landos, 2011). Chronically infected fish like mycobacteriosis, or infected Pseudoloma, of zebrafish are also emaciated (Noga, 2010). Gills may be discussed in gross structure.
Effects of Acute and Chronic Gill Irritation in Fish
Whilst acute irritation may result in excessive mucus, chronic irritation results in hyperplastic changes as seen in myxosporean infection in a condition called hamburger gills. The gill colour should observed; pall gill is the indicator of anaemia and dark brown gills; to nitrite toxicosis (Noga, 2010; Loh and Landos, 2011). Fish with enteric disorders show long faecal tracks and these at times are empty. Fish displaying hexamitiasis can easily appear in this manner or pass white faeces, or faecal casts that unloaded (Loh and Landos, 2011). This is also the way some viral diseases presented (Noga, 2010).
Ultimately, failure to treat the disease on time leads to fatalities. It can be useful to have a little epidemiological history of the course of the mortality events. As an example, when the mortalities (>40%) are high (within short time) both veterinary practitioner suspects environmental (toxins, low DO) and viral diseases. Mid-range deaths and sick fish after more than 1 week period can be signs of other potentially-not-severe infectious diseases (e.g. bacteria, virus), and gradually lethal environmental factors (e.g. low pH). When the degree of mortality is low (<20%) in chronic situations.