Analysis by high-performance liquid chromatography diode array detection mass spectrometry of phenolic compounds in fruit of Eucalyptus globulus cultivated in Algeria

A method based on high-performance liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESI-MS) following fractionation by chromatography on a Sephadex LH-20 column has been developed to determine the phenolic composition of fruit of Eucalyptus globulus growing in Algeria. The presence of 18 gallotannins, 26 ellagitannins, and 2 flavonols was established. Tentative identification is provided for these compounds on the basis of UV-visible spectra and mass spectrometry data. Most compounds described in this study have not previously detected in fruit of E. globulus. Moreover, this is the first report of methyl digalloyl diglucose, 3,3'-O-dimethylellagic acid 4-O-β-glucopyranoside, ellagic acid hexose, methyl ellagic acid pentose, methyltetragalloylglucose, and valoneic acid isomers (sanguisorbic, flavogallic acid dilactone) in the genus Eucalyptus. Quantitatively, ellagic acid and its derivatives, including ellagitannins, are largely predominant.     

Differentiation ofVerticillium dahliae populations on the basis of vegetative compatibility and pathogenicity on cotton

Complementary auxotrophic nitrate-nonutilizing (nit) mutants were used to investigate vegetative compatibility within 27 strains ofVerticillium dahliae isolated from several hosts originating from Africa, Asia, Europe and the United States. Using about 500nit mutants generated from these strains, three vegetative compatibility groups, 1, 2 and 4, were identified. Simultaneously, virulence of each strain was assessed on cultivars ofGossypium hirsutum, G. barbadense andG. arboreum, based upon Foliar Alteration Index (FAI) and Browning Index (BI) estimation. The strains in VCG1 were of both the cotton-defoliating pathotype and race 3 (on cotton) but were non pathogenic on tomato; those in VCG2 and VCG4 were of the nondefoliating pathotype and belonged to different races on cotton and on tomato. Hyaline mutants deriving from parental wild-type strain showed differences in pathogenicity but were always assigned to the parental VCG. A relationship was established between VCGs and the taxonomic position of host plants. Data fromnit pairings indicated that the sub-populations ofV. dahliae (VCGs) may not be completely isolated genetically.     

Regulation of Oestrus ovis (Diptera: Oestridae) populations in previously exposed and naïve sheep

Larvae of Oestrus ovis (Insecta: Diptera: Oestridae) are common parasites of nasal and sinus cavities of sheep and goats. During larval development, a specific immune reaction is initiated by the host with a humoral local and systemic response and the recruitment of eosinophils and mast cells in the upper airways mucosae. Nevertheless, the roles of these responses in the regulation of O. ovis larvae populations in sheep are not yet known. The aim of this study was to compare the establishment and the development of larvae as well as some inflammatory or immune parameters between different groups of half-sibling sheep: (i) a primed group experimentally infected twice before a challenge infection, (ii and iii) two groups infected once only and previously treated with a long-lasting cortico?d before the challenge (one group) or not (the other group). A fourth group of non-infected animals was added in the experimental design. The larval establishment rate was 23% in the cortico?d treated group compared to about 10% in the two other infected groups. Moreover, the larval development appeared more rapid in the cortico?d treated group than in the two other infected groups suggesting that the inflammatory response is involved in the regulation of O. ovis populations. By contrast, no differences in the establishment rates were shown in the primed group compared to the na?ve group (without cortico?d treatment) despite evidence of higher eosinophilia, serum specific IgG, and immediate hypersensibility to excretory-secretory products of larvae. The specific lymphocyte proliferation was reduced in the primed group compared to the na?ve one suggesting that an immuno-suppression occurs following repetitive O. ovis infections.     

Experimental evidence of indirect transmission of Mycoplasma synoviae

The aim of the study was to analyse experimental transmission of Mycoplasma synoviae, an avian pathogen. Three experiments using specific pathogen-free day-old chicks placed in isolators were conducted. In the first experiment, the birds were introduced in an isolator previously contaminated with a M. synoviae broth culture. After 34 days, these birds were eliminated and, for the second trial, the chicks were introduced in the same isolator without disinfecting. In the third assay, the chicks were placed in an isolator containing a mixture of food, feathers and dust collected less than an hour earlier from a M. synoviae infected laying hen flock. In the second and third experiments in order to exacerbate the M. synoviae infection, the birds were inoculated with infectious bronchitis (IB) virus. The presence of M. synoviae in the environment and in tracheal swabs was monitored by culture, a multiplex PCR (mPCR) detecting M. synoviae and Mycoplasma 16S rDNA and a multiplex RT-PCR (mRT-PCR) detecting the M. synoviae mRNA coding for a membrane protein and Mycoplasma 16S rRNA. In in vitro experimental conditions, M. synoviae mRNA and 16S rRNA were detected up to 20 min and 23 h respectively after mycoplasma death. In the first assay, the first infected bird was detected on the 13th day. In the second trial, culturable M. synoviae or viable M. synoviae were detected in the isolator for 3 or 4 to 5 days respectively after depopulation of the birds of the first assay whereas the first culture positive tracheal swabs were detected on the 33rd day, after IB inoculation. In the third experiment, the first infected birds were detected on the 54th day. Thus, the different assays showed that M. synoviae contaminated material (dust, feathers and food) can infect chicks, sometimes after remarkably long silent periods.     

Effects of long-term administration of enalapril on clinical indicators of renal function in dogs with compensated mitral regurgitation

OBJECTIVE: To determine the effect of long-term administration of enalapril on renal function in dogs with severe, compensated mitral regurgitation. DESIGN: Randomized controlled trial. ANIMALS: 139 dogs with mitral regurgitation but without overt signs of heart failure. PROCEDURE: Dogs were randomly assigned to be treated with enalapril (0.5 mg/kg [0.23 mg/lb], PO, q 24 h) or placebo, and serum creatinine and urea nitrogen concentrations were measured at regular intervals for up to 26 months. RESULTS: Adequate information on renal function was obtained from 132 dogs; follow-up time ranged from 0.5 to 26 months (median, 12 months). Mean serum creatinine and urea nitrogen concentrations were not significantly different between dogs receiving enalapril and dogs receiving the placebo at any time, nor were concentrations significantly different from baseline concentrations. Proportions of dogs that developed azotemia or that had a +/- 35% increase in serum creatinine or urea nitrogen concentration were also not significantly different between groups. Conclusions: And Clinical Relevance: Results suggest that administration of enalapril for up to 2 years did not have any demonstrable adverse effects on renal function in dogs with severe, compensated mitral regurgitation.     

Efficacy of hexaflumuron against the fungus-growing termite Pseudacanthotermes spiniger (Sjöstedt) (isoptera,macrotermitinae)

The efficacy of hexaflumuron, a benzophenylurea insecticide, has been studied for the first time on a fungus-growing termite (Pseudacanthotermes spiniger Sjöstedt, Macrotermitinae). Results show that hexaflumuron could be useful in treating infestations of such pest species, which are of great economic importance in many tropical and equatorial countries. Foraging workers harvested and introduced treated food into the nest and subsequently contaminated the brood by trophallaxis. Hexaflumuron showed potent larvicidal activity. The compound did not appear to be rapidly degraded by the digestive enzymes of termite workers, nor by the symbiotic fungus Termitomyces eurhizus Heim growing on fungus combs. This chitin synthesis inhibitor did not act as a fungicide, since growth of the mycelium of this fungus was not inhibited in vitro. © 1998 Society of Chemical Industry     

Utilization of carotenoids from various sources by rainbow trout: muscle colour,carotenoid digestibility and retention

Rainbow trout (Oncorhynchus mykiss) with a mean (sd) weight of 120 (2) g were fed diets supplemented with astaxanthin extracted from the yeast Phaffia rhodozyma (OY1 = 50 mg carotenoids kg^–1 feed, OY2 = 100 mg carotenoids kg^–1 feed), astaxanthin (AX = 100 mg astaxanthin kg^–1 feed) and canthaxanthin (CX = 100 mg canthaxanthin kg^–1 feed) for 4 weeks. Muscle analyses at the end of the experiment indicated a significantly higher carotenoid concentration in the AX group, while CX and OY1 groups were similar in spite of the differences in dietary concentration. The measure of total muscle colour difference (E^* _ab) between initial samples and 4 week ones was higher for the AX fish group but showed no significant difference between OY1, OY2, and CX. The hue and the reflectance ratio (R₆₅₀:R₅₁₀) of fish muscle increased in proportion to carotenoid intake. Digestibility (ADC) of yeast astaxanthin in OY1 and OY2 groups was significantly higher than that in the AX group. Canthaxanthin ADC was about one sixth of that of astaxanthin (AX group). Carotenoid retention in the muscle, expressed as a percentage of carotenoid intake, was higher for the AX group than that recorded for OY1 and OY2. According to ADC, carotenoid retention showed a marked lower value for the CX group. Muscle retentions were similar for astaxanthins from both sources.     

La valeur ornithologique des zones humides de l'est Algerien

In the environs of the town of El Kala in northeast Algeria there are some extensive wetlands of great ornithological, and probably also other biological, importance. The most important are ‘Lake’ Tonga, a marsh of about 2700 ha with much Scirpus lacustris; Lake Oubeïra, a freshwater lake of about 2200 ha; Lake Mellah, where fresh water from brooks and sea water meet, of about 800 ha; Garaet el Mekhada, a Scirpus maritimus marsh of about 5600 ha and swamp forests, which could not be investigated.Many species of waterfowl were seen in the second half of May, 1976. From these and some other observations probable breeding may be derived in many cases. Important species in the region are: squacco heron Ardeola ralloides (about 100 seen), cattle egret Bubulcus ibis (about 2000 seen), little egret Egretta garzetta (about 65 seen), grey heron Ardea cinerea (rare), purple heron Ardea purpurea (about 60 seen, possibly far more present), little bittern Ixobrychus minutus, bittern Butaurus stellaris and night heron Nycticorax nycticorax.Beside herons, the following species were seen: ferruginous duck Aythya nyroca (about 100 seen, probably far more numerous and hidden by the vegetation), white-headed duck Oxyura leucocephala (some 50 seen, probably present in greater numbers), marbled teal Anas angustirostris, purple gallinule Porphyrio porphyrio (common in Tonga). Interesting birds of prey in the region were griffon vulture Gyps fulvus (up to 30), marsh harrier Circus aeruginosus (rather numerous in Tonga), tawny eagle Aquila rapax (probably breeding on one place) and Eleonora's falcon Falco eleonorae (up to 5).As to probable breeding birds, Tonga has the greatest density of species and individuals, but other wetlands also have important aspects.Probably the most important lake for breeding birds, Fetzara (near Annaba), was drained in 1937. Marbled teal, ferruginous duck and purple gallinule were very common there, and white-headed duck, purple heron, squacco heron, night heron, little egret, spoonbill Platalea leucorodia, glossy ibis Plegadis falcinellus, grey-lag goose Anser anser, red-crested pochard Netta rufina and gadwall Anas strepera used to breed.A brief review is given of wintering waterfowl, mainly based on counts by different observers in the period 1971–1979. Large numbers of waterfowl have been seen in Lake Oubeïra; up to 5000 pintail Anas acuta, up to 14000 wigeon Anas penelope, up to 27000 pochard Aythya ferina, up to 9000 tufted duck Aythya fuligula and up to 32000 coot Fulica atra, up to 850 black-necked grebe Podiceps nigricollis and up to 2300 little grebe Tachybaptus ruficollis.In Lake Mellah up to 9000 pochard have been seen, up to 12000 tufted duck, and up to 35000 coot.In Garaet al Mekhada up to 25000 wigeon, up to 5000 coot and up to 8000 grey-lag geese have been seen. It seems quite possible that the 95000 wigeon seen by Smart in the artificial lake of the Barrage de la Cheffia in 1974 fed in Mekhada. An insight of waterfowl averages during the different counts can be obtained from the reports, mentioned in the references.All large wetlands mentioned have a high, actual or potential, ecological value. Each of them deserves protection and, from the ecological viewpoint, Fetzara merits inundation. Protection should be aimed at the preservation of the special character of each of the wetlands and of their mutual relationship for birds.The region is the most important in Algeria for wintering duck and coot (an average of 93000 from 1974–1978) and probably also for breeding waterfowl (especially Tonga) in spite of the high quality of La Macta in West Algeria.For the preservation of this diversity, several factors are essential, e.g., water level, water quality, absence of exotic elements in the water fauna and a relatively low shooting pressure (with little disturbance). It is important to prevent drainage of the lakes and of their surroundings, afforestation of the adjacent land, deforestration and erosion in the catchment areas, introduction of exotic fish species—and it is important to introduce good rules concerning shooting.This complex of wetlands is part and parcel of an extensive area of high biological interest, of which the marine habitats and large semi-natural forests are also remarkable.It is to be hoped that this entity will be efficiently protected in the framework of the National Park of El Kala Project.     

A commercial extract of fruits and vegetables, Oxxynea, acts as a powerful antiatherosclerotic supplement in an animal model by reducing cholesterolemia, oxidative stress, and NADPH oxidase expression

The effects of fruit and vegetable extract (Oxxynea) on plasma cholesterol, early atherosclerosis, cardiac production of superoxide anion, and NAD(P)H oxidase expression were studied in an animal model of atherosclerosis. Thirty six hamsters were divided into two groups of 18 and fed an atherogenic diet for 12 weeks. They received by gavage either water or Oxxynea in water at a human dose equivalent of 10 fruits and vegetables per day. Oxxynea lowered plasma cholesterol and non-HDL cholesterol, but not HDL-cholesterol, and increased plasma antioxidant capacity. It also strongly reduced the area of aortic fatty streak deposition by 77%, cardiac production of superoxide anion by 45%, and p22phox subunit of NAD(P)H oxidase expression by 59%. These findings support the view that chronic consumption of antioxidants supplied by fruits and vegetables has potential beneficial effects with respect to the development of atherosclerosis. The underlying mechanism is related mainly to inhibiting pro-oxidant factors and improving the serum lipid profile.     

Weaning — A challenge to gut physiologists

The aim of this paper is to review the most relevant findings obtained over the last four years on the physiology, microbiology and immunology of the gastrointestinal tract of pigs as influenced by weaning and nutrition in the post-weaning period through the action of feed components or alternative substances to in-feed antibiotics. In recent years, some light has been shed on the physiology of the stomach, including motility, gastric emptying and acid secretion. This organ is important in the control of pathogen entry into the intestines. Recent studies on basic intestinal physiology around weaning have been scarce. Most investigations have been devoted to nutritional approaches on the effects of diet components (e.g. protein, fibre, etc.) and alternative substances (e.g. organic acids, zinc, prebiotics, probiotics, other substances of animal or plant origins) on pig performance and various aspects of gastrointestinal tract physiology, microbiology and immunology. Among these, beneficial effects of some organic acids have been confirmed. Additional data with zinc sources include possible mechanisms of protection. Overall it appears that manipulating carbohydrate (prebiotic) composition of the weaning diet may be the most promising way to improve gut health in weaned piglets. In that respect, consistent results have been obtained with lactose supplementation, and interactions with other feed constituents have been studied. Significant positive results have also been produced with probiotics (bacteria, yeasts) fed to the piglets or to the sows. The major parts of the responses appear to be mediated through changes in gastrointestinal microbiology, including enhanced numbers of favourable bacteria (lactobacilli, bifidobacteria) and/or decreased numbers of potentially pathogenic bacteria (Escherichia coli, Clostridia, etc.) together with more favourable profiles of fermentation products along the intestines. In contrast, measurable effects of these dietary factors on intestinal physiology and mucosal immunology have been limited or difficult to interpret in many cases. Finally, investigations have been conducted with varying diet composition (other than carbohydrates: protein source or level, amino acids, etc) or supplementing with different substances of animal or plant origin. However, positive effects on the gut have often been more variable and sometimes inconsistent.