Scorpion fish

Since sea snake venoms are discussed here, it is appropriate to review other vertebrate venoms also. Unfortunately, very few investigations have been done on the venoms of other marine vertebrates. It is known that some fish secrete venoms from their spines. The fishes known to have venoms are the scorpion fish (family Scorpaenidae), weever fish (family Trachinidae), catfish (order Siluriformes there are 31 families), stargazers (family Uranoscopidae), toad fish (family Batrachoidi-dae), and stingrays (suborder Myliobatoidea). 

Uchimura M, Sandeauz R, Larroque C (1999) The enzymatic detoxifying system of a native Mediterranean scorpion fish is affected by Caulerpa taxifolia in its environment. Environ Sci Technol 33 1671-1674... 

About 250 fish species possess various kinds of venom apparatus. The stingray and scorpion fish belong in this category. Stingrays have a... 

Horse-mackerel Annular bream Scorpion Fish... 

Few studies aimed at understanding the effects of pressure on metabolism in fish have been performed in the Black Sea or Sea of Azov because no distinct stratification was found in the distribution of water animals there. The Sea of Azov is saucer-like, its maximum depth being only 15 m, and in the Black Sea the oxygenated water layer extends only to 150 m depth. However, Emeretli (1996) has shown that activity of lactate dehydrogenase in the liver increases 2-10 times in scorpion fish and annular bream placed in a barorespirometer (designed by A. Stolbov) and sunk to a depth of 300 m. This response seems to be peculiar to shallow-water species (Hochachka and Somero, 1984). 

Table 4 Lipid fractions in muscle and blood serum of horse-mackerel (active) and scorpion fish (sluggish) from the Black Sea, as mg % wet weight of tissue. (After Shchepkin, 1972.)...

In the muscle of active fish such as horse-mackerel and pickerel, the antiox-idative enzymes superoxide dismutase and catalase are more active than in the more sluggish scorpion fish (Rudneva-Titova, 1994 Rudneva-Titova and Zherko, 1994). 

Savina, 1992). Moreover, as these authors and Silkina (1990) note, the white muscle of sluggish fish often exceeds that of highly active species in the characteristics described above. This thesis is supported by the data of Emeretli (1990) on LDH and ATPase activity measured in the muscles of horse-mackerel and scorpion fish (Figure 17). The creatine- and adenylate kinase reactions in the white muscle of sluggish fish appear to proceed at a greater rate than in more... 

Figure 17 ATPase and LDH activity in scorpion fish (white boxes) and horse-mackerel (shaded) in spring (1) summer (2) and autumn (3). R, red muscle W, white muscle. (After Emeretli, 1990)...

Hochachka and Somero, 1977). Even glycogen and glucose are used intensively in red muscle of tuna under aerobic conditions (so-called aerobic glycolysis). In contrast, the sluggish scorpion fish and whiting can perform only relatively slow movements using the white muscle. 

Scorpion fish Turbot Red mullet Whiting Pickerel... 

Proteolytic digestive enzyme activity in sluggish Black Sea fish (e.g. toad goby, scorpion fish) has been found to be equal to and sometimes greater than that of the active fish (e.g. horse-mackerel, annular bream, pickerel). The aminolytic activity of fish of low mobility is also greater (Ugolev and Kuzmina, 1993). It will further be shown in Chapter 5 that the consumption and assimilation of food occur more efficiently in sluggish than in active fish. 

The relationship between the quantity of serum albumin and activity is, however, not clear. Although it forms up to 50% of the serum proteins in tunas, 40% in horse-mackerel, 14% in scorpion fish and 5% in gobies (Shulman and Kulikova, 1966), such a relationship is not distinct in other orders of fish. In the blood it performs transport functions and is an anticoagulating agent. 

Figure 39 Average swimming velocity of fish at different times of the day. (After Belokopytin, 1993.) Solid line, horse-mackerel broken line, pickerel dotted and broken line, scorpion fish.

A considerable quantity of body proteins are also involved in generative synthesis, evidenced by substantial consumption of these proteins during the pre-spawning period by horse-mackerel, red mullet, whiting and pickerel. This would not have occurred if the food proteins had been adequate for the purpose. As horse-mackerel, red mullet and scorpion fish mature, the transport of serum proteins (albumin, a- and 3-globulins) proceeds more intensively (Golovko, 1964 Kondratyeva, 1977). The... 

As Belokopytin (1968, 1978) reported, the percentage of basal metabolism ( b) estimated from standard (Qn) was 40% in highly mobile horse-mackerel and anchovy, 75% in moderately mobile red mullet and about 100% in the sluggish scorpion fish. Sometimes basal metabolism is named supporting metabolism, which is incorrect and leads to misunderstanding. Metabolism and diet support the balanced equilibrium, P = 0. 

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