Resistance of genetically different common carp, Cyprinus carpio L., families against experimental bacterial challenge with Aeromonas hydrophila.

The objective of this study was to determine the differences in disease resistance against artificial infection with Aeromonas hydrophila between genetically different common carp families. Four strains differing in their origin and breeding history were selected from the live gene bank of common carp maintained at the Research Institute for Fisheries, Aquaculture and Irrigation (HAKI, Szarvas, Hungary) to establish families with wide genetic background: Szarvas 15 (15), an inbred mirror line; Tata (T) scaly noble carp; Duna (D), a Hungarian wild carp and Amur (A), an East Asian wild carp. A diallele mating structure was used to allow the assessment of genetic variation within and between the tested 96 families for a variety of traits. The existing technologies of fertilization and incubation of carp eggs, as well as larval and fingerling rearing had been modified because of the large number of baseline populations. Two challenge trials of the 96 families of carp with Aeromonas hydrophila were done. The 10 most resistant and 10 most susceptible families to A. hydrophila were identified from these two challenges. The crosses that produced the most resistant families were mainly those having parents from Tata and Szarvas 15 domesticated strains, while the most susceptible families were from the wild strains Duna and Amur.

The use of immunostimulating herbs in fish. An overview of research.

The use of immunostimulants as an alternative to the drugs, chemicals and antibiotics currently being used to control fish diseases in fish culture is attracting the attention of many researchers. In this context, many have focused on the use of medicinal plant products as potential therapeutic measures for modulating the immune response and, specifically, on the use of herbs to prevent and control fish diseases. Medicinal plants (plant remedies) are a deeply rooted component of the cultural heritage of many people from diverse cultures and countries and are, as such, closely linked to the maintenance of good health. The aim of this paper is to review research currently being carried out on the herbs and herbal extracts that have been shown to modulate the immune system of fish. Special attention is given to the use of Chinese and Indian herbs.

Chinese herbs (Astragalus radix and Ganoderma lucidum) enhance immune response of carp, Cyprinus carpio, and protection against Aeromonas hydrophila.

The effect of Chinese herbs (Astragalus radix and Ganoderma lucidum) on immune response of carp was investigated. Fish were fed diets containing Astragalus (0.5%), Ganoderma (0.5%) and combination of two herbs (Astragalus 0.5% and Ganoderma 0.5%) for 5 weeks. Other groups of fish were vaccinated (i.p.) against Aeromonas hydrophila/Aeromonas salmonicida (Shering Plough, Essex, U.K.) at the beginning of the experiment and fed the same diets as described above. Control fish (negative control) and fish vaccinated only (positive control) were fed basal diets without supplements of herbs. The respiratory burst activity, phagocytosis, lysozyme activity and circulatory antibody titres in plasma were monitored. Following 5 weeks after feeding, fish were infected with A. hydrophila and mortalities were recorded. The results of this study showed that feeding non-vaccinated and vaccinated carp with combination of Astragalus and Ganoderma stimulated respiratory burst activity, phagocytosis of phagocytic cells in blood and lysozyme and circulatory antibody titres in plasma in vaccinated carp. Fish challenged with A. hydrophila had variable survival. The best survival (60%) was in vaccinated group fed with both herbs, while almost 90% of control fish (negative control) and 60% of fish vaccinated only (positive control) died.

Effects of Pulp and Paper Mill Effluent (BKME) on Physiology and Biochemistry of the Roach (Rutilus rutilus L.)

The effects of bleached kraft pulp and paper mill effluent (BKME) on the roach (Rutilus rutilus L.) were studied under experimental and natural field conditions. In the acute experiment (72 h exposure to the concentrated BKME), the roach suffered from a general stress syndrome, characterized by a significant increase of cortisol and blood glucose, as well as a significant decrease of leucocrit and total plasma protein. In three weeks' exposure in a polluted and an unpolluted lake and in fish caught from the same lakes, the more specific effects of BKME treatments appeared. During the three weeks' exposure, slight hyperglycaemia as well as a decrease in a transaminase activity (GPT) and increase in the plasma total protein concentration of the fish occurred in the polluted lake. Fish caught from the polluted lake exhibited lower values of haematocrit, transaminases (GOT and GPT), and calcium concentration plus a higher chloride concentration in the plasma than in the unpolluted lake. The differential leukocyte counts also showed slight differences: Fewer lymphocytes and more granulocytes were found in roach from polluted waters. The morphology of the red blood cells in the roach from polluted lakes had more elongate erythrocytes with a longer major axis and a shorter minor axis than in fish from the polluted lake. The possibilities of determining the origin of fish based on their erythrocyte morphology is discussed.

Age-dependent changes in transmembrane signalling: identification of G proteins in human lymphocytes and polymorphonuclear leukocytes.

In human neutrophils (PMNLs) we found that in the elderly IP3 formation was significantly decreased compared to that of young subjects. For FMLP receptor binding affinity and number no measurable differences occurred upon ageing, studying both the low or the high affinity receptors. The amount of ADP-ribosylated G proteins, catalysed by pertussis toxin (PT) or cholera toxin (CT), was significantly increased in PMNLs of the elderly. In lymphocytes, the PT-catalysed ADP ribosylation of G proteins was also increased with ageing, while the CT-catalysed ribosylation was decreased. The autoradiogram of [32P]ADP-ribosylated proteins by CT in lymphocytes of young individuals showed a major polypeptide of 40,000 M(r). In contrast, in lymphocytes of the elderly, the major polypeptide was 45,000 M(r). In PMNLs, CT labelled quite strongly the 45,000 M(r) band, mainly in the elderly. When PT was used, no age-related pattern changes could be demonstrated, while differences could be observed between the two types of cells. The use of antiserum P680 (G alpha common) showed no age-related pattern changes, while the intensity of the labelled proteins varies with age and cell type. The antiserum U46 (Go alpha) could identify in lymphocytes of young subjects two polypeptides 68,000 and 41,000 M(r). The prominent polypeptide in lymphocytes of the elderly was the 70,000 M(r) and no other polypeptides could be recognized. In PMNLs of young subjects the U46 and serum identified a range of species. In PMNLs of the elderly all these bands were weakly labelled. The present data indicate changes in the pattern and the quantity of G proteins in lymphocytes and PMNLs of elderly subjects.