Sprat

Sprosstmg,/. sprouting, etc. (see sprossen). Sprotte,/. sprat (Clupea vprattua). 

Sprat, Thomas.Hi story of the Royal Society by Thomas Sprat. Edited by Jackson I. Cope and Harold Whitmore Jones. Edited by Jackson I. Cope and Harold Whitmore Jones. St Louis Washington Univ. P., 1958. 

Thomas Sprat, History of the Royal Society, ed. Jackson I. Cope and Harold W. Jones. (St. Louis Washington University and London Routledge, Kegan and Paul, 1959) 134138. 

On Aristotle, Ortony, Metaphor and Thought, 3 on "plainnesse" in the new scientific language, Thomas Sprat, History of the Royal Society, 111, 113 and, more recently, Steven Shapin and Simon Schaffer,... 

Self-selection of foods has not been studied from the standpoint of individual differences. We know by observation that some individuals have a "sweet tooth," that "Jack Sprat can eat no fat," etc., but we have no idea except by inference how these characteristics fit in with the metabolic peculiarities of the individuals concerned. 

TABLE I. RESULTS OF AC IMFEDANCE AND SALT SPRAT TESTS FOR DIFFERENT SURFACE TREATMENTS... 

Within each of two Black Sea species, anchovy (warm water) and sprat (cold water), both the concentrations and absolute amounts of phospholipids fluctuate within similar limits, but do not change during the annual cycles in the same tissues. This contrasts with, for example, the considerable differences between the phospholipid contents of red and white muscle or between that of either of them and liver (Shchepkina, 1980a Shchepkin and Minyuk, 1987). The content of polyenoic acids in the phospholipids of anchovy is higher than that in the sprat (Yuneva, 1990) possible explanations will be given in Chapter 3. 

There is a strong interannual variation in the lipid concentration in the flesh of planktivorous fish such as anchovy, kilka and sprat, which is governed by the varying abundance of the plankton (Shulman, 1972b, 1996 Luts and Rogov, 1978 Luts, 1986). 

Fish from temperate zones have been most studied, and from these we learn that temperature may influence the character of metabolic rhythm both indirectly, through food supply, and directly, through the limited temperature ranges within which one or other vital activity can or cannot occur. It is the response or the preference that fish show to temperature that shapes the rhythmic pattern. This is well shown in two diametrically opposite fish from the Black Sea, the warm-water anchovy and the cold-water sprat (Figure 34). The curves that describe the course of triacyl-glycerol accumulation in these species mirror each other, as the fish oppose one another in their time of spawning. 

Figure 34 Lipid accumulation and withdrawal (schematic) in different months by the anchovy and sprat. (After Shulman, 1978a.) Continuous line, sprat broken line, anchovy.

Temperature affects food supply in another way also. The Mediterranean sprat, which prefers cold waters, exploits a wider feeding area than fish that inhabit only warm waters, because it takes advantage of a greater water depth and can feed all the year round. It possesses a much greater lipid reserve than the warm-water anchovy, and its range of fatness over the annual cycle is wider (Figure 36). The feeding conditions in the warm Mediterranean waters are therefore more favourable to fish that prefer cooler waters rather than warm. 

Figure 36 Annual lipid cycle in anchovy (broken line) and sprat (continuous line) in the Mediterranean. (After Shulman, 1978a.)...

Long-term fluctuations in lipid accumulation by Black Sea sprat during the summer post-feeding period, when their fat reserve is at its peak, were observed from 1960 to 1994 and this work continues (Shulman et al.t 1994). Interannual variability in the lipid content, though small, is real, with a coefficient of variation of 12-15%, as estimated at certain points of this period of time. 

Table 10 shows seasonal variation in the age composition of Black Sea anchovy and sprat. The weight of an average fish in a population is evaluated from the age structure of the population and the share of the total biomass contributed by each age group. In horse-mackerel, pickerel and whiting, the proportion of the different age groups keeps stable all the year round, while in... 

Table 10 Average age composition of Black Sea anchovy and sprat (% of biomass).

Figure 52 Seasonal changes in somatic and generative growth in populations of anchovy and sprat (mg g-1 fresh tissue) solid line, proteins broken line, lipids dotted and broken line, mineral matter and glycogen.

When the production of different Black Sea fish is compared, the six species investigated divide roughly into two groups, one comprising anchovy and sprat and the other, pickerel, whiting, horse-mackerel and red mullet. The sizes and biomasses of fish within a group are similar, as are some biological features. 

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