Cyprinid Fish Species Research Articles

The food, growth and abundance of five co-existing cyprinids in lake basins of different morphometry and water quality

The food, growth and abundance of five co-existing cyprinid fish species in the eutrophic Lake Hiidenvesi were studied. The diet overlaps within the cyprinid community in shallow lake basins were compared with those in a deep basin, where littoral resources are less available. Roach, bleak and white bream inhabited both the shallow and the deep parts of the lake. Their growth rate was slow, probably due to the low availability of animal food, indicated by the increasing proportion of detritus and plant material in the diets towards the end of the summer. In the deep basin, roach and bleak, contrary to white bream, did not forage on the very abundant invertebrate Chaoborus flavicans, explained by the migration behaviour of C. flavicans. Blue bream, unlike other cyprinids, utilized copepods and had a relatively fast growth rate, but was mostly restricted to the shallow areas. The condition of the bream stock was weak both in terms of growth and abundance. The availability of zoobenthos was low and bream was not able to compete for zooplankton with the more specialized planktivores.

A model system for keeping spawners of wild and domestic fish before artificial spawning

In this paper we present a system with controlled temperature and photoperiod for keeping breeders before their artificial spawning and give a general outline of its use. The advantages of this system were: utility, small area in which it was placed, wide range of temperature and photoperiod, possibility of worked tanks together or alone and in open, closed or semi-closed systems, cheap to construct and with low running costs. Additionally, this unit was tested for artificial spawning for several wild and domestic European cyprinid and percid fish species, as well as burbot, not uncommonly in different periods than the time of their natural spawning.

Morphometric analysis of axial muscle in cyprinid fish provides support that intracellular lipid plays a role in slow fibre oxygen supply*

In the present study, slow axial muscle of three species of cyprinid fish, Danube bleak, nase and chub, was examined for intracellular lipid. Data from fish held under constant conditions in the laboratory (with and without locomotory exercise training) were compared with data from fish living in the wild. The laboratory‐reared fish (trained and untrained) as well as the fish from the wild showed species‐dependent differences of intracellular lipid content in their slow muscle, with values being higher in Danube bleak than in nase and chub. This suggests that accumulation of intracellular lipid within slow muscle fibres is partly under the influence of factors other than environmental ones, for example, capillary density. To test whether intracellular lipid facilitates oxygen transport from capillaries to mitochondria within the muscle fibres in those fish with a relatively low capillary density but high lipid content, this work also quantified slow muscle capillary supply. Under each life regime, the capillary densities for chub and nase were higher than those for Danube bleak. The negative correlation of intracellular lipid and capillary density is in favour of this supposition.

The reproductive cycle of the endangered cyprinid Alburnus albidus: Morphological changes of the gonads and plasma sex steroid fluctuations

Alburnus albidus is an endangered and little known cyprinid fish species endemic in southern Italy. Histological characteristics of testes of A. albidus from River Alento, Campania Region, were analysed every month between January‐July 1996. Depending on the relative abundance of spermatogonia, spermatocytes, sper‐matides and spermatozoa in the testes, we devided the gonadal cycle into four stages: 1. quiescence, when mainly spermatogonia were present (January‐February); 2. recrudescence, when spermatocytes were abundant, although spermatids were also detectable (March‐April); 3. spawning, when cysts contained all stages of germ cells (May‐June); 4. Postspawning, when testes contained spermatogonia only (July). The concentration of sex steroids (an‐drogens, 17 α‐hydroxyprogesterone and 17 β‐estradiol) fluctuated throughout the year. Androgen levels were high during the quiescence and the spawning periods. 17 α‐hydroxyprogesterone concentration showed a sharp increase just before the spawning period. 17 β‐estradiol levels were quite low, with the exception of a slight increase during the recrudescence and the spawning periods.

Polyploid Hosts: Strange Attractors for Parasites?

While a major force in higher plant evolution (Stebbins 1971, 1977), polyploidy is largely restricted among animals to lower vertebrates such as fish, amphibians and reptiles (Ohno 1970, Bogart 1980, Schultz 1980). Interestingly, many polyploid fish species occur in the African cyprinid family (Oellerman and Skelton 1990, Golubtsov and Krysanov 1993, Doadrio 1994, Guegan et al. 1995). Although cases of host-parasite associations in polyploid host species are absent in the literature, they are of interest because they permit comparative study of host-parasite adaptation. We aim to show here that polyploid host species may harbour higher parasite species richness than their diploid relatives, and in this context, studies of polyploids and their associated parasites may considerably help evolutionary ecologists and parasitologists to better understand hostparasite interactions. We have studied monogenean ectoparasites of North and West African freshwater fishes. The occurrence of monogenean host specificity is attributed to independent specialization which has evolved for reasons other than interspecific competition that can include host-parasite coevolution (Klassen and Beverley-Burton 1989, Guegan and Agnese 1991, Van Every and Kritsky 1992), enhancement of mating by congeners (Rohde 1989), or avoidance of hybridization (Euzet and Combes 1980). Patterns in monogenean community richness and organisation among host species have been explained by host body size and age (Guegan et al. 1992), host geographical range and latitudinal gradients (Rohde 1989), host diversity (Rohde 1989, Guegan and Kennedy 1993), or host phylogeny (Guegan and Kennedy 1993). We used the infracommunity species richness observed on the richest host individual (richness values are ranked from 0 to 13 across host species), for 29 African cyprinid fish species and a total of 618 collected specimens, and this data were regressed against the 6 independent variables: host species body size, geographical range, host diversity defined as the number of species per fish genus, host species phylogeny, latitudinal gradients (West and North Africa), and host species ploidy level (threefold levels of ploidy were found: 2n = 50, 2n = 100, 2n = 150). To address the question of whether the parasite species richness is correlated with some traits of their hosts, we applied both simple and multiple regression procedures (Sokal and Rohlf 1981). Generally, closely related host species are more likely to exhibit similar development than distant species (Felsenstein 1985, Pagel and Harvey 1988), and they cannot be treated as statistically independent points. For instance, a relationship between parasites and host ploidy level across all fish species may be a result of phylogenetic history since fish species that share common descent are likely to be subject to similar evolutionary constraints and are likely to exhibit similar ploidy level. Comparative methods have recently been proposed to take this non-independence into account, considering phylogeny fixed and controlling for its effect on regressions (Harvey and Pagel 1991). Here, we used the independent comparisons method (Pagel 1992, Purvis and Rambault 1994, 1995) to identify a set of independently evolved comparisons within fish taxa. The host phylogeny was obtained from morphological data together with molecular data. We made a second control for sampling effort (defined as the number of collected specimens per fish species), as uneven sampling bias affects richness estimates (Gregory 1990, Walther et al. 1995). For all regressions, host body size, host geographical range and host diversity logarithmic values were used (Harvey 1982). Parasite species richness values were log (x + 1) transformed. Across species of cyprinid fishes, the number of parasite species observed correlates positively, in decreasing order of significance, with host body size (r = 0.53, p = 0.001), host diversity (r = 0.45, p = 0.001), host phylogeny (r = 0.35, p = 0.001) and host ploidy level (r = 0.21, p = 0.005). The number of parasite species a fish species harbours does not correlate significantly with neither host latitude (r = 0.06, p = 0.186)

Myxobolus cypriniDoflein, 1898, in Peamouth: First Report of This Myxosporean in the Western Hemisphere

Abstract A survey of 3–8-year-old peamouths Mylocheilus caurinus collected from the lower Fraser River, British Columbia, revealed 100%, infection by a myxosporean identified as Myxobolus cyprini based on spore morphology, site of infection, and associated pathological changes. Myxobolus cyprini is a common myxosporean parasite of several species of cyprinid fishes (family Cyprinidae) in Europe, the former USSR, and China, but this is the first report of this myxosporean in the Western Hemisphere. The source of the infection in peamouths—whether the parasite is endemic to North America or has been imported with exotic cyprinids from Europe or Asia—is unknown. It is also possible that the myxosporean from peamouths is very closely related to, but a distinct species from, M. cyprini of Eurasia. As reported from European cyprinid fishes, the myxosporean in peamouths developed in the skeletal muscle, and disseminated spores were found associated with chronic inflammation in the visceral organs.

EFFECTS OF INTRINSIC AND EXTRINSIC FACTORS ON POPULATION FRAGMENTATION IN THREE SPECIES OF NORTH AMERICAN MINNOWS (TELEOSTEI: CYPRINIDAE)

Geographic patterns of genetic variation (mitochondrial DNA [mtDNA] and allozymes) were used to examine effects of intrinsic characteristics (e.g., vagility, habitat specificity, and reproductive behaviors) and extrinsic factors (e.g., climatic and geological history) on population fragmentation. The three species of cyprinid fishes examined (Tiaroga cobitis, Meda fulgida, and Agosia chrysogaster) occupied similar historical ranges within the lower Colorado River drainage, but differ in intrinsic characteristics conducive to population fragmentation. Relationships among populations were similar across species, reflecting common historical influences, but results indicate the distribution of variation among species is strongly affected by intrinsic characteristics. Variation within two species (T. cobitis and M. fulgida) is subdivided among populations, suggesting little gene flow among rivers. In contrast, similarity of A. chrysogaster populations throughout the Gila River drainage supports the hypothesis that levels of gene flow are high for this species. Levels of mtDNA divergence were much higher than expected for both T. cobitis and A. chrysogaster suggesting long-term isolation of geographic regions. These results indicate that both long-term and short-term extrinsic factors have shaped basic patterns of variation within these fishes; however, the intrinsic characteristics of each species have strongly affected the population genetic structure of these fishes.

Some aspects of the reproductive biology ofBarbus spp.,Capoeta damascina and their hybrids (Cyprinidae, Teleostei) in Israel

The reproductive biology and gonad cycle of three Cyprinid fish species:Barbus canis (Valenciennes, 1842),B. longiceps (Valenciennes, 1842) andCapoeta damascina (Valenciennes, 1842), in the upper Jordan River system of Israel were studied by monthly sampling over a two-year period. The reproductive activity of the three species was found to peak from January to April, mostly involving upstream migration towards spawning grounds on river beds 400–900 m above the Jordan River. Hybrids of the three species were collected in nature: in those ofBarbus canis ×Capoeta damascina, the gonads possessed both types of gametes, spermatogonia and oogonia, all of which became arrested at an early stage of development, and infertile; in hybrids of detected in nature, males had oocytes dispersed in the testis, whereas in females, the ovaries had small islets of spermatogonial tissue. In these female hybrids the oocytes ripened normally and spawning occurred.

Opisthorchiasis and pseudomphistomiasis in the Republic of Tatarstan

On the vast territory of the Republic of Tatarstan, 4 large rivers of the European part of Russia flow: Volga, Kama, Belaya, Vyatka with their numerous tributaries. They are inhabited by an abundant flora of cyprinid fish species, which serve as a source of infection with opisthorchiasis, pseudomphistomiasis and metorchiasis. For the first time, opisthorchiasis in the republic was registered by us in 1957 (in Laishevsky, Kuibyshevsky, Rybno-Slobodsky, Alekseevsky, Kamsko-Ustyinsky, Yelabuga, Aktanyshsky, Zelenodolsky, Tetyushsky and Mamadyshsky districts).

Evidence for an unusual ZW/ZW'/ZZ sex-chromosome system in Scardinius erythrophthalmus (Pisces, Cyprinidae), as detected by cytogenetic and H-Y antigen analyses.

Fifty-seven individuals of the European cyprinid fish species Scardinius erythrophthalmus were sexed by gonad histology, and their karyotypes were analyzed by Giemsa staining and C-banding. The chromosome number in somatic metaphase plates was 2n = 50. Karyotypes of all gonadal male animals were identical, consisting of 48 small meta- or submetacentric chromosomes and a pair of large metacentric chromosomes (ZZ males). Of the 33 gonadal females, 16 had a karyotype similar to the males' (ZW' females) and 17 had a heteromorphic pair of chromosomes, including a large metacentric Z chromosome and a small acrocentric W chromosome (ZW females). H-Y antigen typing with cells obtained from a variety of tissues revealed that the homogametic ZZ males were H-Y negative and the heterogametic ZW females were H-Y positive in all tissues tested. In contrast, ZW' females showed no expression of the H-Y antigen in somatic cells but were H-Y positive in ovarian cells. These results suggest that the ZW/ZW'/ZZ sex chromosomes of S. erythrophthalmus represent an unusual system of sex determination and that H-Y antigen expression is coupled with the heterogametic sex. Whether the ZW' individuals are indeed heterogametic females or actually sex-reversed ZZ males, in which chromosomal sex determination is overruled by external factors, is discussed.

Characterization of nucleolar organizer regions of twelve species of Chinese cyprinid fishes

SUMMARYSilver staining technique was used to study the chromosomal NORs of 12 species of Chinese cyprinids. The NOR number varies from 2 to 7. Only a single pair of NOR-bearing chromosomes was detected in 5 species respectively. The remaining species each possess two or more pairs of NOR-bearing homologues. NORs may be located at submetacentric, subtelocentric or metacentric chromosomes. NOR heteromorphism was common. Finally, it is suggested, in the discussion, that further studies should be made on the overall Cyprinidae.

Cupular Growth Rate of Free Neuromasts in Three Species of Cyprinid Fish.

The cupulae of cyprinid larval fish became deformed or disappeared by anesthesia in MS 222 solution, but when the larva was transferred to MS 222 free water, the cupulae began to grow again. The growth rate of newly extending cupulae was examined after treatment wish the MS 222 solution. The rates were 8.7-10.6 μm/h in Gnathopogon elongatus caerulescens, 10.3-11.3μm/h in Carassius auratus grandoculis, and 8.9μm/h in Zacco platypus. These findings suggest that complete replacement of the treated cupulae would take about 24h in the larvae of these species.

Chromosomal heterochromatin differentiation of cyprinid fishes

The chromosomes of 10 species of Chinese cyprinid fishes were analyzed by means of C-banding technique. It has been found that there is extensive variation in the constitutive heterochromatin among these fishes. Some of these species possess considerable quantities of heterochromatin, and some possess little heterochromatin. These results seem to show that constitutive heterochromatin has played an important part in the chromosomal evolution of cyprinids.

Effects of Intraspecific Variation on Phylogenetic Inference: A Likelihood Analysis of mtDNA Restriction Site Data in Cyprinid Fishes

The comparative analysis of DNA molecules is a useful means for phylogenetic reconstruction, because different types of genetic elements yield resolution at different levels of taxonomic divergence. A single individual is usually characterized for each operational taxonomic unit (OTU), based on the premise that within-OTU variation can be safely ignored. Whereas that premise is expedient, it may not be generally valid. Sometimes variation within OTUs can affect the analysis. We develop a formal analytic treatment of variation in phylogenetic output as a consequence of intraspecific variation. Using restriction site data from the mitochondria of three species of cyprinid fishes to illustrate, we show that genetic variation within taxa impacts on tree topology

Aaptosyax grypus, a new genus and species of large piscivorous cyprinids from the middle Mekong River

A new genus and species of cyprinid fishes,Aaptosyax grypus, is described from the middle Mekong River of Laos and Thailand, This large and rarely seen species reaches a full meter in length and lives in the main stem of the river. The species is a piscivore and the southernmost representative of the aspiin lineage. Among the aspiins it is unique in having a well-developed adipose eyelid and large symphyseal knob on the mandible which fits into a deep notch in the upper jaw.

Human Opisthorchis and Haplorchis infections in Laos

A study of the epidemiology of trematode infections was carried out in Vientiane province, Laos, comprising examination of snails, fish, cats, and human stools. Opisthorchis viverrini cercariae were found in the snail Bithynia siamensis goniomphalus (Bithyniidae) and Haplorchis taichui cercariae in Tarebia granifera (Thiaridae). O. viverrini metacercariae were recorded in the flesh of 7 species of cyprinid fish; metacercariae of the heterophyid fluke Haplorchis taichui were found in 4 species of cyprinid fish and those of H. pumilio in 2 species. Cats from the same localities were infected with O. viverrini and 4 species of heterophyid flukes, frequently as multiple infections. The highest prevalence of small fluke eggs in human stools was recorded in the 20–29 years age group, particularly in males (90·4%). Three-quarters of human infections were light (< 1000 eggs/g), the highest value (2975 eggs/g) being recorded in the 10–14 years age group. Identification of small flukes excreted by Laotian patients after treatment with praziquantel in Czechoslovakia revealed more cases with H. taichui than with O. viverrini. The results confirmed the simultaneous occurrence of O. viverrini and intestinal heterophyid flukes in the area studied.

Diurnal Variation in Membrane Lipid Composition of Sonoran Desert Teleosts

ABSTRACT Phospholipid molecular species and headgroup compositions were determined for sarcoplasmic reticular and microsomal membranes in two species of Sonoran desert cyprinid fish (Agosia chrysogaster Girard and Notropis lutrensis Girard) trapped in an isolated pool of a desert stream. Fish populations were sampled in the cool of the morning (water temperature 21–21·9°C for Agosia and 22–26°C for Notropis) and 7–11 h later in the heat of the afternoon (water temperature 34·2°C) to determine whether membrane lipid composition varied with sampling time and thermal exposure. The composition of sarcoplasmic reticular membranes did not vary significantly through the day. In contrast, the molecular species composition of muscle microsomes (a mixture of endoplasmic reticulum and plasma membranes) changed markedly from the cool of the morning to the heat of the afternoon in both species. Adjustments were particularly striking in phosphate dylcholine (PC). For example, in Agosia, the ratio of saturated-to-unsaturated species of PC, the unsaturation index (the average number of double bonds per molecular species) and the proportion of diunsaturated molecular species decreased from 7·48 to 0·77, from 1·36 to 0·35 and from 7·23% to 2·46%, respectively, between the morning and afternoon samples. Similar, but less dramatic, changes were noted for phosphatidylethanolamine (PE) in both species, and for phosphatidylinositol (PI) in Notropis. In addition, microsomal membranes of Agosia exhibited a significant reduction in the proportion of PE (from 12·1 to 2·7 %) and a corresponding increase in the proportion of PC between the morning and afternoon samples. These patterns of change in membrane lipid composition are in a direction consistent with thermal compensation of membrane function and suggest that rapid adjustments in the lipid composition of biological membranes may stabilize membrane structure against substantial diurnal fluctuations in temperature.

Notropis melanostomus, a New Species of Cyprinid Fish from the Blackwater-Yellow River Drainage of Northwest Florida

pharyngeal tooth formula of 4-4 and high number of anal rays (10-12) makes it unique for Notropis, except for possible confusion with N. ortenburgeri, which exceeds its size and has 9-11 anal rays. Notropis melanostomus has thin, nearly embedded scales, a black peritoneum, numerous long gill rakers, large eyes, and a variable cephalic lateral line system. Although more abundant than its original scarcity indicated, its preferred habitat is rapidly being encroached by commercial and domestic development.

New bariliin cyprinid fishes from West Africa, with a consideration of their biogeography

Five new species of bariliin cyprinid fishes are described from West Africa. Three belong to the genus Leptocypris and two to Raiamas. One species of each genus is from Guinea (Konkoure river) and from Sierra Leone (Taia and Little Scarcies rivers), the other, a Leptocypris, is from Cameroon (Cross River). A taxon of indeterminate generic identity from Guinea is also described. The phylogenetic relationships of the bariliins are hypothesized and in this light their geographical distribution is compared with that of other cladistically analysed African freshwater fish groups. The significance to West African fish distribution of the Togo-Benin (Dahomey) Gap is discussed.

Effects of Black Spot Disease on Thermal Tolerances and Condition Factors of Three Cyprinid Fishes

Abstract The influence of black spot disease, a metacercarial infestation, on thermal tolerances (critical thermal maximum, CTMax, and critical thermal minimum, CTMin) and fish condition factor (KTL) was examined in three cyprinid fish species: spotfin shiner Notropis spilopterus, bluntnose minnow Pimephales notatus, and striped shiner Notropis chrysocephalus. Metacercarial counts of 2 to 535 per fish had little or no effect on the CTMax or CTMin of any of the three species tested. Likewise, metacercarial counts were not correlated with fish condition factor. Although some fish species are affected adversely by black spot disease, these three cyprinid species apparently are tolerant of even heavy infestation by metacercariae.