bluuebunny/crossref_metadata_2025 huggingface dataset:
Health effects of vegetarian and vegan diets
Authors: Key Timothy J. , Appleby Paul N. , Rosell Magdalena S.
Published: January 2006

Vegetarian diets do not contain meat, poultry or fish; vegan diets further exclude dairy products and eggs. Vegetarian and vegan diets can vary widely, but the empirical evidence largely relates to the nutritional content and health effects of the average diet of well-educated vegetarians living in Western countries, together with some information on vegetarians in non-Western countries. In general, vegetarian diets provide relatively large amounts of cereals, pulses, nuts, fruits and vegetables. In terms of nutrients, vegetarian diets are usually rich in carbohydrates, n−6 fatty acids, dietary fibre, carotenoids, folic acid, vitamin C, vitamin E and Mg, and relatively low in protein, saturated fat, long-chain n−3 fatty acids, retinol, vitamin B12 and Zn; vegans may have particularly low intakes of vitamin B12 and low intakes of Ca. Cross-sectional studies of vegetarians and vegans have shown that on average they have a relatively low BMI and a low plasma cholesterol concentration; recent studies have also shown higher plasma homocysteine concentrations than in non-vegetarians. Cohort studies of vegetarians have shown a moderate reduction in mortality from IHD but little difference in other major causes of death or all-cause mortality in comparison with health-conscious non-vegetarians from the same population. Studies of cancer have not shown clear differences in cancer rates between vegetarians and non-vegetarians. More data are needed, particularly on the health of vegans and on the possible impacts on health of low intakes of long-chain n−3 fatty acids and vitamin B12. Overall, the data suggest that the health of Western vegetarians is good and similar to that of comparable non-vegetarians.
Differences in serological responses to specific glycopeptidolipid-core and common lipid antigens in patients with pulmonary disease due to Mycobacterium tuberculosis and Mycobacterium avium complex
Authors: Fujita Yukiko , Doi Takeshi , Maekura Ryoji , Ito Masami , Yano Ikuya
Published: January 2006

Disease due to the Mycobacterium avium complex (MAC) is one of the most important opportunistic pulmonary infections. Since the clinical features of MAC pulmonary disease and tuberculosis (TB) resemble each other, and the former is often difficult to treat with chemotherapy, early differential diagnosis is desirable. The humoral immune responses to both diseases were compared by a unique multiple-antigen ELISA using mycobacterial species-common and species-specific lipid antigens, including glycopeptidolipid (GPL)-core. The results were assessed for two patient groups hospitalized and diagnosed clinically as having TB or MAC pulmonary disease. Diverse IgG antibody responsiveness was demonstrated against five lipid antigens: (1) monoacyl phosphatidylinositol dimannoside (Ac-PIM2), (2) cord factor (trehalose 6,6′-dimycolate) (TDM-T) and (3) trehalose monomycolate from Mycobacterium bovis Bacillus Calmette-Guérin (BCG) (TMM-T), and (4) trehalose monomycolate (TMM-M) and (5) GPL-core from MAC. Anti-GPL-core IgG antibody was critical, and detected only in the primary and the secondary MAC diseases with high positivity, up to 88·4 %. However, IgG antibodies against Ac-PIM2, TDM-T and TMM-T were elevated in both TB and MAC patients. Anti-TMM-M IgG antibody was also elevated in MAC disease preferentially, with a positive rate of 89·9 %, and therefore, it was also useful for the diagnosis of the disease. IgG antibody levels were increased at the early stages of the disease and declined in parallel to the decrease of bacterial burden to near the normal healthy control level, when the anti-mycobacterial chemotherapy was completed successfully. Unexpectedly, about 25 % of hospitalized TB patient sera were anti-GPL-core IgG antibody positive, although the specificity of GPL-core was sufficiently high (95·8 % negative in healthy controls), suggesting that a considerable number of cases of latent co-infection with MAC may exist in TB patients. Taken together, the combination of multiple-antigen ELISA using mycobacterial lipids, including GPL-core and TMM-M, gives good discrimination between healthy controls and sera from patients with TB or MAC disease, although for accurate diagnosis of TB more specific antigen(s) are needed.
Enterotoxicity and genetic variation among clinical Staphylococcus aureus isolates in Jordan
Authors: Naffa Randa G. , Bdour Salwa M. , Migdadi Hussein M. , Shehabi Asem A.
Published: January 2006

A total of 100 Jordanian clinical Staphylococcus aureus isolates was analysed for the presence of the enterotoxin genes sea, seb, sec, sed and see using multiplex PCR. Twenty-three isolates (23 %) were potentially enterotoxigenic. The prevalence of sea, sec and sea plus sec among the total clinical isolates was 15, 4 and 4 %, respectively. None of the isolates harboured sed, seb or see genes. S. aureus isolates were subjected to DNA fingerprinting by randomly amplified polymorphic DNA (RAPD) analysis to test whether isolates harbouring the toxin genes were genetically clustered. A total of 13 genotypes was identified at a 47 % similarity level. Genotypes I and V accounted for the largest number of enterotoxigenic isolates (19 %). This study has demonstrated the genetic diversity of Jordanian clinical S. aureus isolates and shown that the presence of the toxin genes is not genotype specific.
Kodamaea (Pichia) ohmeri fungaemia in a premature neonate
Authors: Taj-Aldeen S. J. , Doiphode S. H. , Han X. Y.
Published: January 2006

Kodamaea ohmeri is a yeast that rarely causes human infections. The first case of K. ohmeri fungaemia in a premature neonate is reported; it was successfully treated with liposomal amphotericin B. Biochemical identification of the yeast was performed by Vitek II and API and was confirmed by rRNA gene sequencing. K. ohmeri as a human pathogenic yeast is uncommon to hospitalized neonates and immunocompromised individuals.
High ampicillin resistance in different biotypes and serotypes of Haemophilus influenzae colonizing the nasopharynx of healthy school-going Indian children
Authors: Jain Amita , Kumar Pradeep , Awasthi Shally
Published: January 2006

Haemophilus influenzaeis one of the main causes of otitis media, sinusitis, meningitis, pneumonia and septicaemia in children, and the development of ampicillin resistance inH. influenzaeis a cause of serious concern. The aim of the present study was to determine the prevalence of ampicillin resistance inH. influenzaecolonizing the nasopharynx of school-going healthy North Indian children, and to compare the distribution of different biotypes and serotype b in this population. A total of 2400 school-going healthy children from 45 rural and 45 urban schools were enrolled. Nasopharyngeal swabs were collected from the children and cultured.H. influenzaewas isolated from 1001 (41·7 %) of the 2400 nasopharyngeal swabs collected. All theseH. influenzaeisolates were biotyped and serotyped, and their antibiotic susceptibility tested. All eight biotypes were present in this population. The most prevalent biotypes were I (19·6 %), II (16·8 %) and III (25·0 %). Of the 1001 isolates, 316 (31·6 %) wereH. influenzaetype b and 685 (68·4 %) were non-type bH. influenzae, and 22·9 % were resistant to ampicillin, 41·9 % to chloramphenicol, 27·5 % to erythromycin and 67·3 % to co-trimoxazole. Of the 316H. influenzaetype b isolates, 44·0 % were ampicillin resistant, while only 13·1 % non-type bH. influenzaeisolates were ampicillin resistant. Of the 229 ampicillin-resistantH. influenzaeisolates, 196 (85·6 %) were positive forβ-lactamase; 93·4 % (214/229) were biotypes I, II and III, of which 49 % were biotype I, 27·9 % were type II and 16·6 % were type III. Most of the strains belonging to biotypes III–VIII were ampicillin sensitive. Ampicillin resistance is significantly more common in biotype I and serotype b than in other biotypes and serotypes.
The compelling effects of compulsory schooling: evidence from Canada
Authors: Oreopoulos Philip
Published: January 2006

Abstract.  Compulsory school laws have existed for more than a hundred years, and policies to mandate further education continue to be discussed. The implications of these laws, however, are not well understood. Historical changes to compulsory schooling in Canada permit an examination of their effects on would‐be‐dropouts under very different circumstances than those during changes in other countries. Mandating education substantially increased adult income and substantially decreased the likelihood of being below the low‐income cut‐off unemployed, and in a manual occupation. These findings suggest significant gains from this legislation, which seem unlikely offset by the costs incurred while having to remain in school. JEL classification: I20, I28
Can we obtain realistic parameter estimates for the ‘protection for sale’ model?
Authors: Mitra Devashish , Thomakos Dimitrios D. , Ulubaşoğlu Mehmet
Published: January 2006

Abstract.  In the Grossman and Helpman (1994) model of endogenous trade protection, sectoral lobbies try to influence an incumbent government that maximizes a weighted sum of political contributions and aggregate welfare. We empirically investigate this model using U.S. and Turkish data. Our specification is more tightly tied to theory than those in existing studies. Additionally, we assume all specific‐factor owners to be organized into different lobbies. These changes, validated by hypothesis tests, yield more realistic parameter estimates of the government's concern for aggregate welfare and of the fraction of population organized into lobbies.
Ins, outs, and the duration of trade
Authors: Besedeš Tibor , Prusa Thomas J.
Published: January 2006

Abstract.  We employ survival analysis to study the duration of U.S. imports. Our findings indicate international trade is far more dynamic than previously thought. The median duration of exporting a product to the U.S. is very short, on the order of two to four years. There is negative duration dependence. If a country is able to survive in the exporting market for the first few years it will face a very small probability of failure and will likely export the product for a long period of time. The results hold across countries and industries and are robust to aggregation. JEL classification: F14, F19, C14, C41
The effect of Methallibure on spermatogenesis in Poecilia reticulata
Authors: Martin P. , Bromage N. R.
Published: January 2006

Methallibure treatment in Poecilia reticulata resulted in an interruption of spermatogenesis. This inhibition occurred at the stage of transformation of secondary spermatogonia to primary spermatocytes. The possible endocrine nature of this inhibition is discussed and it is suggested that treatment with Methallibure might provide a suitable alternative to surgical hypophysectomy in the study of pituitary‐gonad relationships in teleosts.
An historical review of the fish and fisheries investigations of the Freshwater Biological Association, mainly at the Windermere Laboratory
Authors: Bagenal T. B.
Published: January 2006

This paper is a review of most of the research work on fish that has been carried out by the Freshwater Biological Association, and includes not only what has been done at Windermere, but also some past work carried out elsewhere. However, current work at the River Laboratory, which is now a separate establishment, has been excluded.

The history of the Association i s traced from its formation in 1929 and its first laboratory at Wray Castle, to its present quarters at the Ferry House. Thc pre‐war work of Allen on trout, perch and salmon is described and an account is given of the war time research and fishery for eels and perch, and of how this has led to the experimental removal of perch and pike from Windermere on a large scale. The physiological research, and work on trout fry, on char and other species, as well as many subsidiary investigations, are mentioned. As far as possible brief summaries of the main results are given for most of the 99 papers mentioiicd.
Production of salmon and trout in a stream in Scotland
Authors: Egglishaw Henry J.
Published: January 2006

For three years the population size, rates of growth, standing stock, production and yield of all year classes of salmon and trout within three sections of a stream in Scotland were studied. Total salmon production as fresh weight per m2 was 6.5 g in 1966, 10.6 g in 1967 and 11.1 g in 1968, and total trout production was 10.3g in 1966, 12.3 g in 1967 and 7.7g in 1968. Fish of 0+ and 1+ year old provided usually more than 90% of the total annual salmon production and 80 % of the annual trout production. Yield of salmon smolts (about 9 cm or longer after 2 years growth) per m2 was 0.10 in 1966, 0.22 in 1967 and 0.15 in 1968. The smolt yield by weight was 29 % of the production of the 1966 year class of salmon and 16% of the 1967 year class. Numbers of trout of 9 cm or longer produced in the same time were higher and their weight was 60% of the total production of the 1966 year class and 32% of the 1967 year class.
Notes on the biology of the schelly Coregonus lavaretus (L.) in Haweswater and Ullswater
Authors: Bagenal T. B.
Published: January 2006

Some aspects of the biology of the schelly Coregonus lavaretus (L.) were investigated by examining 188 that had passed down an aqueduct from Haweswater and 437 that were caught in gill nets set in Ullswater.

In both lakes the main breeding season is from mid January to mid February, and in Ullswater spawning takes place in shallow water [less than 7.6 m (25 feet)] on a sandy bottom with stones and weed, at the entrance to a bay. The males in Haweswater first spawn when 3 years old and in Ullswater when 2; and the females first spawn in Haweswater when 4 years old, and in Ullswater when 3.

Scales were kept from every fish and were found suitable for age determination. Some Haweswater schelly live for 9 years, but from Ullswater the oldest was 8. The rate of growth of male Haweswater schelly was very well described by the equation:
image

(where lt(=the length at time t) but the curve had to be transposed a further year to describe adequately the Ullswater male schelly growth. It is clear that the rates of growth are similar in the two lakes after the first year, during which it is much faster in Ullswater.

A study of the length‐weight relation showed that the weight is proportional to the length cubed, and no difference in condition was found between males and females.

The schelly egg was found to be slightly sticky, spherical and 2.98 mm in diameter. Some fertilized eggs were kept at various constant temperatures. At 4°C and 6°C the death rate was low, but was higher at 8°C and total mortality occured at 10°C. This low upper lethal temperature probably restricts the spawning season to mid‐winter and also limits the species' geographical range, as has also been suggested for the char Salvelitms alpinus (L.) whose eggs have similar temperature requirements.

Some eggs were reared to adults, and these provided corroboration of the validity of the scales for age determination. Two other points mentioned in this paper were the occasional winter strandings of schelly, and the incidence of a supernumerary pelvic fin.
The relationship of gonadal development to the life cycles of the paired species of lamprey, Lampetra fluviatilis (L.) and Lampetru planeri (Bloch)
Authors: Hardisty M. W.
Published: January 2006

Gonadal developnient has been studied throughout the larval period of Lumpetru fluviatitis and comparisons have been made with conditions in the larvae of the closely relatcd non‐parasitic species, L. planeri. The two forms differ in the time of onset or mitotic division in germ cells and in the period when oogenesis is initiated. These phases begin in L. pluneri when the ammocoetes are one year old and in L. fluviatilis at the end of the second year. The course of sex differentiation appears to be sinlilar in both forms. While in the early stages, the oocytes of L. planeri are larger than those of L. fluviatilis. at comparable ages, by the end of the third year they are sinlifar in size in both spccics. It is suggested that in L. planeri, during the extension of the larval period, gonad growth is retarded and during this phase the ammocoete accumulates body reserves which are used to meet the metabolic requirements of the rapidly developing gonads after metamorphosis. The differences observed in early gonadogenesis are believed to account for the reduced fecundity of the L. planeri ammococtc and their adaptive significance is discussed.
Growth control of Saprolegnia from UDN‐infected Atlantic salmon Salmo salar L.
Authors: Hodkinson M. , Hunter A.
Published: January 2006

Nine antiseptic compounds, at concentrations ranging from O.1 to 0.0001 %, were tested in vitro for their ability to inhibit the growth of Saprolegnia. This fungus was isolated from suspected UDN‐infected Atlantic salmon. Malachite green was the most effective antiseptic. Fungal growth was completely inhibited at all the concentrations tested.
Composition and nutritive value of some grasses, plants and aquatic weeds tested as diets
Authors: Tan Yee Thong
Published: January 2006

The composition and nutritive value of different diets, namely the aquatic weeds—Hydrilla verticillata (L.f.) Presl., Lemna gibbs (L.) Pistia stratiotes (L.), grasses—Guinea grass Panicum maximum Jacq., Napier grass Pennisetum purpureum Schum. and plants—sweet potato leaves Ipomaea batatas L. and tapioca leaves Manihot utilissimus Pohl. were determined and compared. The diets contained 13.5 to 30.48% protein; 1.89 to 9.60% fat; 3.94 to 23.13% ash; 5.42 to 26.70% fibre and 24.87 to 46.27% carbohydrate. Most of the minerals determined in the aquatic weeds were higher than those in grasses and plants. The feeding of Hydrilla, Napier grass and tapioca leaves to grass carp Ctenopharyngodon ideltus (V.) showed a different growth rate and the results obtained indicated the superiority of Hydrilla diet over Napier grass and tapioca leaves.
Effects of gossypol on rainbow trout Salmo guirdneri Richardson
Authors: Herman Roger Lee
Published: January 2006

Rainbow trout were fed gossypol acetate or cottonseed meals containing gossypol for 14 months. Toxic effects were indicated by growth depression, reduced hematocrit, hemo‐globin, and total plasma protein. Histological changes were noted, particularly in the liver and kidney.
The decline of a roach Rutilus rutilus (L.) population in Chew Valley Lake
Authors: Wilson R. S.
Published: January 2006

A series of nettings for roach in Chew Valley Lake carried out by members of the Zoology Department, Bristol University, has revealed a marked decline in the population between 1965 and 1968. Fish from the main Lake were found to be heavily parasitized with Ligula intestinalis (L.) while those from the inflow pool (Herriott's Pool) were practically free from infection. It is considered that the decline of the roach can be linked to the incidence of Ligula, but that clean fish from the inflow pool may provide breeding stock and maintain the production of fry, which serve as food for the trout.
The Swiss/ICR (Ha) albino mouse as an experimental host for infectious pancreatic necrosis virus of trout
Authors: Angiolelli R. F. , Rio G. J.
Published: January 2006

Intracranial inoculation of infectious pancreatic necrosis virus (IPNV), a pathogen of several species of trout, produced pancreatic necrosis in suckling Swiss albino mice. Peri‐nuclear halos, cytoplasmic vacuoles, and necrosis were found in histologic sections of pancreas taken from mice killed 21 days post‐inoculation. Virus was recovered from the pancreas of mice killed as early as 10 days post‐inoculation. Rivers' postulates were fulfilled. Virus recovered from the infected mouse pancreas was neutralized by IPNV specific antiserum. The significance of the mouse as an experimental host is discussed.
The influence of exposure to low temperature on Tilapia mossambica Peters (Cichlidae).
Authors: Allanson B. R. , Bok A. , Van Wyk N. I.
Published: January 2006

In the cichlid teleost Tilapia mossambica secondary chill coma following exposure to 11° C in freshwater is associated with decreases in plasma osmolarity, sodium and chloride ion concentrations. Fish exposed in seawater diluted to give a NaCl concentration of 5%0 show no signs of coma nor are there decreases in osmolarity or sodium and chloride ion concentrations.

It is suggested that the restrictions of T. mossambica to estuaries at the southern end of its distribution in southern Africa relates to the maintenance of near normal sodium and chloride ion concentrations at low temperatures during winter.
Induced spawning in carp with fractionated fish pituitary extract
Authors: Slnha V. R. P.
Published: January 2006

Three different fractions of fish pituitary extract obtained by molecular sieving of the whole pituitary extracts on Sephadex G‐100 (Sinha, 1969a) have been tested for effectiveness in inducing spawning of members of the carp family. Fish differing in their spawning habits were chosen‐bighead carp and silver carp do not spawn at all in captivity, whereas Puntius and common carp spawn freely. Gravid fish injected with the second fraction alone showed courtship behaviour and ovulated viable eggs. None of the fish injected with the first fraction or the third fraction showed any courtship behaviour nor did they ovulate. The second fraction from the pituitary extract of free spawner or non‐spawner, immature or mature, male or female was found effective in inducing spawning in both the free spawner and non‐spawner gravid females. Clearly this suggested that this fraction contains either an active gonadotropin or a gonadotropin releasing factor. However, unlike the free spawner, these non‐spawners do not breed in captivity unless injected with an additional amount of the second fraction or the whole pituitary material. The cause of this is still difficult to explain. Synthetic mammalian hormones such as FSH, LH, mixed mammalian anterior pituitary and chorionic hormone, ACTH and posterior pituitary hormones have failed to induce courtship behaviour and ovulation. Oxytocic activity of the fractions showed that there was no correlation between spawning activity and the rat uterus activity. Also these fractions did not contain any appreciable amount of arginine vasotocin. Thus it is suggested that isotocin/arginine vasotocin is not the principle responsible for spawning in these fish.
The systematic status of the Mediterranean centracanthid fishes of the genus Spicara, and in particular S. chryselis (Valenciennes), as indicated by electrophoretic studies of their eye‐lens proteinst†
Authors: Pollard D. A. , Plchot P.
Published: January 2006

The systematic history of the Mediterranean centracanthid fishes is reviewed and the past and present nomenclatural confusion in this group, most of which appears to have been due to the occurrence of colour polymorphism coupled with sex inversion, is discussed. The question of the probable systematic status of Spicara chryselis is raised, and in particular whether it should be regarded as a separate species or merely a colour form of one of the other two Mediterranean species (S. smaris and S. maena) belonging to this genus. The results of both electrophoretic studies of their eye‐lens proteins and morphological studies of these three forms are discussed, and the conclusion is drawn that S. chryselis is but a chromatic ecophenotype of the polymorphic species S. maena. The occurrence of such habitat‐associated colour polymorphism coupled with sex inversion is compared with a similar phenomenon previously observed in the labrid Corisjulis. The potential value of electrophoretic studies of eye lens proteins in the solution of such complicated intra‐ and inter‐specific systematic problems is emphasised.
Recent changes in the movements of adult salmon Salmo salar L. in the Tay‐Tummel‐Garry system, Scotland
Authors: Gardner Michael L. G.
Published: January 2006

Records from salmon counters at hydro‐electric dams, and of angling results, in the Tay‐Tummel‐Garry river system are analysed. Spring runs of ascending salmon have decreased since at least 1950, but summer and autumn runs have increased since 1959. Hydro‐electric developments are not responsible for these changes, nor for the decrease in the average weight of salmon in the system. Possible environmental factors are discussed, and a method suggested whereby the ratio of sizes of salmon populations in branches of a river system may be estimated. The numbers of descending kelts have recently increased, but the times of downstream migration have not changed.
Temperature tolerance and thyroid activity of the white perch Roccus (=Morone) americanus
Authors: Mc erlean Andrew J. , Brinkley H. J.
Published: January 2006

The seasonaliy of temperature tolerance using thiourea‐treated, normal and thyroxine treated white perch was determined after laboratory acclimation and LD50 values calculated by normit analysis. Treatment effects, reflected in slight shifts in LD50 values were evident. However, these did not fit a consistent pattern of thyroidal involvement in temperature tolerance.

When specimens of known thyroidal functional state were used in tolerance tests, results, similar to the seasonal tolerance tests, were obtained. Thus, although the white perch has a functioning thyroid capable of forming radiohormone and this capability was experimentally varied in these tests, no tolerance shifts were noted.

Data obtained in tolerance testing were statistically adjusted to partition out variation due to differences in acclimation temperatures (season) and to test for treatment (thyroidal functional state) effects. Treatment difference was not significant while that due to season was significant (P<0.01). Thyroidal functional state was thus unrelated to tolerance.
Hydrocephalus and red‐disease in pike fry Esox lucius L.
Authors: Bootsma R.
Published: January 2006

Two diseases of pike fry have been investigated, both causing serious losses in Dutch pike culture. In one of these diseases the lump developing on the head of the fry was associated with an internal hydrocephalus.

The other one, ‘red disease’ after the haemorrhagic areas in the trunk, may be identical with red‐sore disease of pike.

The etiologies of both diseases are unknown.
On the generic relationship of the sciaenid fish Bola chaptis Hamilton, with a description of specimens from Burma
Authors: Trewavas Ethelwynn , Talwar P. K.
Published: January 2006

A species of sciaenid fishes is described from Burmese waters and identified with Bola chaptis Hamilton. On account of the structure of its swim‐bladder and other features it is placed in the same genus, Bahaba, with B. flavolabiata Lin, a species of Chinese and Korean waters.
Studies on ulcerative dermal necrosis of salmonids
Authors: Roberts Ronald J. , Shearer W. M. , Munro A. L. S.
Published: January 2006

Six salmon Salmo salar (L.) were vaccinated with an extract of normal salmon skin, to elicit production of anti‐epithelial antibodies. These were produced within 8 weeks and were readily detectable by immunofluorescence, no evidence for the presence of similar antibodies in UDN infected salmon or normal salmon or trout was obtained. Experimental traumatization of the skin of vaccinated salmon with dry ice failed to produce Pemphigus type lesions and it was concluded that UDN was not an auto‐immune disease of the pemphigus type.
Neogobius fluviatilis in Lake Balaton—a Ponto‐Caspian goby new to the fauna of central Europe
Authors: Biró Péter
Published: January 2006

A new species of Ponto‐Caspian Neogobius fluviatilis is reported from Lake Balaton. This is the most western occurrence in central Europe. The main taxonomic marks and the distinguishing features from the related species are discussed and the geographical ranges are summarized. The immigration into Lake Balaton, the successful acclimatization indicated by spawning and some ecological characters are also discussed.
A simple electronic smolt counter
Authors: Weiss D. M.
Published: January 2006

The development of methods for the automatic counting of migratory fish has become a matter of some importance in the United Kingdom and elsewhere, owing to the increasing concern over the lack of accurate information about fish stocks. An instrument capable of counting fish accurately and reliably in a variety of conditions remains a goal towards which progress is being made only slowly, despite strenuous efforts by a number of organizations.

The fish counters available at present are expensive to buy and sufficiently complex to be difficult to build by the majority of workers in fisheries management, but there are, however, circumstances where fish may be counted by relatively simple means and an example of this is given below.

It was found that salmon smolts swimming down a channel or tube could be reliably detected using a simple electronic circuit which was sensitive both to changes in resistance across 2 electrodes set in the water flow, and to the rate of change of resistance. These changes were amplified sufficiently to produce deflections on a recording meter so that subsequent examination of the chart gave both a count of the smolts and also the time of passage.

Details of the circuit, which can be built at low cost and with only elementary equipment, are discussed briefly and some of the results are given.
Immune relations between mother and foetus in the viviparous poeciliid fish Xiphophorus hellerii Haeckel
Authors: Hogarth P. J.
Published: January 2006

Ectopic implantation of Xiphophorus causes the accelerated rejection of subsequent grafts of antigenically similar adult tissues; conversely, prior transplantation of adult tissues causes the accelerated rejection of subsequent grafts of related embryos. Xiphophorus embryos carry adult histocompatibility antigens before birth; the failure of the embryo to elicit a maternal immune response during gestation is not due to antigenic immaturity.
Immune relations between mother and foetus in the viviparous poeciliid fish Xiphophorus hellerii Haeckel
Authors: Hogarth P. J.
Published: January 2006

Allografts within the ovary are rejected as rapidly as those made elsewhere; the Xiphophorus ovary is thus not a favoured site for allograft survival because of high gonadal hormone levels. Removal of one embryo of a brood from the ovary and its reimplantation elsewhere does not affect the development of the remaining members of the brood. Immune rejection of the foetus during gestation is not avoided by the absence of lymphatic drainage from the ovary.
Trout in Llyn Alaw, Anglesey, North Wales. I. Population structure and angling returns
Authors: Hunt P. C. , Jones J. W.
Published: January 2006

An account is given of the survival and contribution to sport fishing of stocked trout and natural river trout in the impounded reservoir, Llyn Alaw, in Anglesey, North Wales. Scales from 2143 trout caught by angling and netting during the first four years after impoundment were used to determine the age and origin of Llyn Alaw fish. The success and future of Llyn Alaw as a trout fishery are discussed.
Trout in Llyn Alaw, Anglesey, North Wales. II. Growth
Authors: Hunt P. C. , Jones J. W.
Published: January 2006

The annual and seasonal growth, length/weight relationship, changes in seasonal condition and specific growth rates of 17 types of trout in the newly flooded reservoir, Llyn Alaw, in Anglesey, North Wales, were investigated. Scales and length‐weight data from 2076 trout caught by angling and netting during the first 4 years after impoundment were analysed to show the age, origins and growth of all fish both before and after flooding.
Some aspects of the biology of gudgeon Gobio gobio (L.) in Irish waters
Authors: Kennedy Michael , Fitzmaurice Patrick
Published: January 2006

Data on some aspects of the biology of gudgeon were obtained during a programme of research on Irish coarse fishes. Eggs of gudgeon, were collected on 3 occasions—on June 8 and again on June 29, 1965 in a small rivulet entering a hydro‐electric reservoir in Co. Cork; and on June 2, 1966 in a millstream on the Grand Canal in Co. Dublin. The eggs were greyish‐white in colour, opaque, and 1·375–1·625 mm diam. Newly‐hatched larvae from eggs from Co. Cork measured 5·45 mm and were distinguished by the presence of black pigment largely confined to the ventral aspect of the yolk sac and tail. They began to feed after 3 days; in 5–6 days the yolk was fully absorbed, the fish then measuring 6·2 mm. Following the creation of 2 hydro‐electric reservoirs on the River Lee in Co. Cork, large populations of gudgeon developed in them for a time. It was found that, in the reservoirs, gudgeon less than 7·5 cm were feeding mainly on Cladocera, especially Chydoridae. The larger reservoir gudgeon and gudgeon in rivers and streams in Co. Cork fed mainly on molluscs, Gammarus, chironomid larvae, caddis larvae and ephemeropteran nymphs. Some gudgeon held a good deal of filamentous algae. Gudgeon were aged by means of scale reading, the results of which were confirmed by length‐frequency distribution analysis in the case of the reservoirs. In the Lee system, gudgeon grew relatively rapidly at first, attaining a mean fork‐length at 3 years old of 9·5–10·8 cm according to year‐class. In the River Allow, a Cork Blackwater tributary, early growth was slower than in the Lee, but the length increments in the third and subsequent seasons were bigger than in the Lee reservoirs. In the Lee, most gudgeon of both sexes spawned for the first time when 2 years old, at a minimum fork‐length of 6·9 cm in the case of males and 7·9 cm in the case of females. The trematode parasite Paracoenogonimus ovatus was of frequent occurrence in Irish gudgeon aged 2 years and upwards.
Gonadal hydration response and major electrolyte levels in serum and seminal fluid of Puntius gonionotus (Teleostei) injected with the fractionated fish pituitary extract
Authors: Sinha V. R. P.
Published: January 2006

Fractions of the pituitary extracts which were successfully used for induced spawning of certain carps have been tested in the present investigation to assess the gonadal hydration response in Lampam jawa Puntius gonionotus. The levels of major ions in the serum and seminal fluid were determined to see if there is any obvious change following the treatment. The gonadal hydration response was induced only by the injection of the second fraction, which fraction was thought to contain the gonadotropin or a gonadotropin releasing factor. A possible role of gonadotropin in osmoregulation has been indicated.
The haematological assessment of the health of freshwater fish
Authors: Blaxhall Peter C.
Published: January 2006

A review is made of some selected literature regarding the use of haematological techniques in freshwater fish pathology. Comparisons are drawn with the techniques already widely used in human pathology for the assessment of health and for aid in diagnosis of various diseases and conditions. The need for information on normal values, and on the conditions under which these were formulated, and the factors affecting them is stressed. The use of haematological values in assessing sublethal concentrations of environmental pollutants and the possibility of chromosomal changes are considered.
Observations on the inflammatory response within the dermis of a white bass, Morone chrysops (Rafinesque), infected with Lernaea cruciata (Copepoda: Caligidea)
Authors: Joy James E. , Jones Larry P.
Published: January 2006

Infection of a serranid fish, Morone chrysops, with the adult female ‘anchor worm’Lernaea cruciata was accompanied by an inflammatory response characterized by an extensive proliferation of fibrous connective tissue elements Both the dermis and musculature of the host were involved. No mineralization of tissues was observed. This constitutes the first report of L. cruciata from M. chrysops.
Sulphamerazine toxicity in cut‐throat trout broodfish Salmo clarki (Richardson)
Authors: Smith Charlie E. , Holway Jamieson E. , Hammer Glen L.
Published: January 2006

Treatment of cut‐throat trout broodfish Salmo clarki (Richardson) with Sulphamerazine at 220 mg/kg (10 g/100 1b) of fish/day for 14 days resulted in severe kidney histopathology and increased mortality among males. Experimental data presented showed that cut‐throat trout broodfish were extremely sensitive to Sulphamerazine toxicity. Hydropic degeneration of renal tubule epithelium and haemorrhage into tubule lumens were observed in kidneys of both male and female trout, but was more severe in the former. Death, which occurred only in males, was correlated with spawning stress and impaired renal function.
Plasma proteins of the goosefish Lophius piscatorius (L.)†
Authors: Jimenez Maximo , Planas Jose
Published: January 2006

117 goosefish plasma from the Mediterranean coast have been analysed. Total plasma proteins gave mean values of 2.8±0.9 for males and 3.3±1.1 g/100 for females. The cellulose acetate and starch‐gel electrophoresis showed 7 and 13 fractions respectively. Different albumin patterns were observed but their distribution did not have a genetic basis. In 107 specimens a mean TIBC value of 278 ± 125 μg Fe% was found. The saturation coefficient of the transferrin was from 15–20%. The specimens had a single Tf band and one individual had a slower Tf band. The presence of an haptoglobin polymorphism has been suggested. The plasma haptoglobin concentration by an electrophoretic method was determined and a concentration from 28–31 mg Hp% was obtained.
Toxicity of rotenone to some species of coarse fish and invertebrates
Authors: Meadows B. S.
Published: January 2006

The toxicity of rotenone was determined for seven species of fish and three species of invertebrates. The results show that there is a marked variation in sensitivity of different species to rotenone. The survival times of roach Rutilus rutilus (L.) were reduced by a rise in temperature and also by a reduction in water hardness. Temperature affected the rate at which rotenone is degraded; 3 days after being prepared a solution containing 2 mg/1 of 5 % rotenone was non‐toxic to roach over a 7‐day period at 20°C, but it was still toxic for at least 11 days at 11.5°C. The data are discussed in relation to the use of rotenone in fisheries management.
The food and feeding interrelationship of the fishes in the Lagos Lagoon
Authors: Facade S. O. , Olaniyan C. I. O.
Published: January 2006

The food of 26 common fish species of the Lagos lagoon are given. It is shown that the food of the species covers a wide spectrum and most of the available invertebrates are being utilized as food by the fishes. The intra and interspecific relationship of the food and feeding habits of the various species are discussed.
First record of the freshwater eel Anguilla dieffenbachii Gray to be caught at sea
Authors: Todd P. R.
Published: January 2006

A female A. dieffenbachii caught off the New Zealand coast has ova of 0.45 mm to 0.50 mm in diameter; these ova are larger than those observed in seaward migrating females of this species. The estimated percentage of gonad weight to total body weight of 11.2% is significantly greater than that observed in migrating females of the same size, but other migratory features, such as the eye size, colour, head and pectoral fin shape, are identical.
Studies on the skin of plaice (Pleuronectes platessa L.)
Authors: McQueen A. , Mackenzie K. , Roberts Ronald J. , Young Hamish
Published: January 2006

Eighty‐nine O‐group plaice from a natural population were exposed at 15°C to heavy infection by Cryptocotyle lingua cercariae. Subsequently 45 fish were retained at 15°C, whilst 44 were held at 5°C. Both groups were sampled by killing individual fish at intervals of 6,18,42 h and daily thereafter up to 710 h. Entire fish were fixed immediately in formol saline, transversely sectioned and stained by H & E, PAS, PAS‐diastase, JSDB 109, Picro‐Mallory, Masson's trichrome, Gram‐Weigert and Alcian blue. Histopathological observations showed: (a) epidermal lesions associated with encysted metacercariae in adjacent tissues; (b) myofibrillar necrosis associated with bacteria possibly introduced by the parasite; and (c) a reactive swelling of the intermuscular septa. The progressive development of the parasite cyst and host capsule is described. Development of both was markedly inhibited at the lower temperature, but the inflammatory response at either temperature was slight. This may be evidence of a long‐standing host‐parasite relationship which has evolved to an advanced state of adaptation on the part of the parasite and tolerance on the part of the host.
The establishment of a ‘normal’ population and its behavioural maintenance in the guppy—Poecilia reticulata (Peters)*
Authors: Warren E. W.
Published: January 2006

Populations of the guppy—Poecilia reticulata (Peters)—were established with a single male and female fish per compartment. In spite of excess food, regular water changes, constant temperature and continuous aeration, the populations eventually reached a stable asymptote which was proportional to the size of the compartment, particularly when the populations were visually isolated from other populations. A weight asymptote was achieved some time after the population plateau. There was a tendency for females to exceed the numbers of males at the asymptote. Fish from the asymptotes were rearranged to relatively increase or decrease the populations, on the expectation that the populations would revert to the original asymptote. This did not happen. It was hypothesized that there was a learned behavioural response which prevented reproduction in the altered populations, but not an ovarian ‘carry‐over’ for the ovaries of decreased and increased populations were distinguishable. The learning hypothesis was substantiated in fish of a single generation which were crowded, then uncrowded, and continued to show reduced courtship and increased aggressive behaviour.
A note on the upper lethal temperature of juvenile Haemulon flavolineatum from the Virgin Islands
Authors: Sylvester J. R.
Published: January 2006

Lethal temperature relations of a sample of juvenile French grunts, Haemulon flavolineatum (Desmarest), were studied. The Critical Thermal Maximum (CTM) and resistance times at four elevated temperatures were determined. Exposure time is considered to be of prime importance in studies of thermal tolerance.
The size of the eggs of the Argentine anchovy, Engraulis anchoita (Hubbs & Marini) in relation to the season of the year and to the area of spawning*
Authors: de Ciechomski Janina D.
Published: January 2006

The problem of egg size variations in the Argentine anchovy Engraulis anchoita has been studied in relation to the different seasons of the year and to the different spawning centres within the geographical area. It has been stated that there exist significative differences in egg dimensions between the northern and the southern spawning centre of the reproduction area. Taking into account other biological characteristics of the anchovy from both centres it is suggested that these variations could indicate that the spawning stock is divided into two main genetic groups. It has been found that the average size of anchovy eggs decreases as the spawning season progresses.
Respiratory responses of the striped mullet, Mugil cephalus (L.) to hypoxic conditions*
Authors: Cech Joseph J. , Wohlschlag Donald E.
Published: January 2006

Ventilation volume, ventilatory frequency, ventilatory stroke volume, percentage utilization of oxygen and respiratory metabolism were measured on unanaesthetized striped mullet, Mugil cephalus L., under ambient and hypoxic conditions with a modified van Dam respiration chamber. Hypoxia caused a statistically significant increase in ventilation volume, ventilatory frequency, and ventilatory stroke volume and a significant decrease in percentage utilization of oxygen. The routine rate of respiratory metabolism was not significantly altered by hypoxia. These responses probably represent ventilatory adjustments which serve to maintain a constant oxygen supply to the gills under conditions of oxygen depletion.
Diet and intestinal helminths in a population of perch, Perca flavescens
Authors: Cannon L. R. G.
Published: January 2006

In 1967 and 1968 1310 Perca flavescens (Mitchill) were examined from Lake Opeongo, Ontario for changes in five diet categories and in incidence of eight intestinal helminths in relation to seasons, host size and sex. Male fish were less common than females and were smaller. A high proportion of fish (57.7 %) had empty stomachs, but of the four types of foods taken microcrustacea were high in spring, late summer and again in early winter; insects increased in summer with another peak in autumn; crayfish had a small peak in spring and a larger one in autumn; and fish were lowest in summer. Males ate more smaller foods (microcrustacea) than females, but females ate more larger foods (crayfish and fish); no sex difference was seen with regard to insects or empty stomachs. Male fish ate very few larger items, but females showed an increase in food size with increasing size of fish. There was no seasonality in incidence of fish free of all parasites, but two trematodes Bunodera sacculata Van Cleave & Mueller and B. luciopercae (Müller), and one cestode Proteocephalus pearsei La Rue showed seasonality with populations lowest in fish in summer; and one trematode Crepidostomum cooperi Hopkins and one nematode Dacnitoides cotylophora Ward & Magath showed seasonality with populations highest in summer. In addition one cestode Bothriocephalus sp., one nematode Spinitectus gracilis Ward & Magath and one acanthocephalan Leptorhynchoides thecatus (Linton) showed no seasonality, perhaps on account of the low incidence in the case of Bothriocephalus sp. and L. thecatus. No parasites were more common in males, but two (P. pearsei and L. thecatus) were more common in females. In both males and females, with increasing size fish, (i) fish free of all parasites decreased, but (ii) incidence of C. cooperi increased. Incidence of B. luciopercae, Bothriocephalus sp., S. gracilis and L. thecatus all increased with increasing size of fish only in females. The relationship between diet and incidence of intestinal helminths is discussed in the light of what is known of their life cycles. The exercise illustrates our ignorance of population ecology of fish parasites and the interactions of parasites and their host populations.
Validation of an in vivo method for monitoring ovarian development in the grey mullet (Mugil cephalus L.)
Authors: Shehadeh Ziad H. , Kuo Ching‐Ming , Milisen Kathy K.
Published: January 2006

The validity of using extruded intra‐ovarian oocytes for in vivo assessment of ovarian maturity in the grey mullet was established. The diameter of sampled, unfixed oocytes was used as a reference point for comparative purposes. Analysis of variations in oocyte diameters among samples removed from seven different ovarian locations indicated that mullet oocytes develop in synchrony and that in vivo samples taken from any area in the ovary would be representative of the entire ovary. Statistical analyses of oocyte diameters and diameter‐frequency distributions data from duplicate in vivo samples removed from the same ovarian site in each of 17 females showed no significant differences and validated the accuracy of the method. Similar comparisons of data from in vivo and in vitro samples revealed no statistically significant differences.
The haemoglobins of Labeo umbratus (Smith) and Labeo capensis (Smith)
Authors: Du Toit P. J. , Hattingh J. , Schabort J. C.
Published: January 2006

The haemoglobins of both L. umbratus and L. capensis separated into four components on polyacrylamide electrophoresis. The isoelectric points of these fractions were found to be 9.35, 6.89, 6.63 and 6.40. Organic nucleotide triphosphate concentration in the blood of L. capensis was found to be 56.72 ± 18.01 mg% and 58.72 ± 17.9 mg% in the case of L. umbratus. It is not possible to distinguish between L. umbratus and L. capensis purely on the basis of the haemoglobin electropherogram.