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71.
The importance of dietary HUFA for meagre larvae (Argyrosomus regius; Asso, 1801) and its relation with antioxidant vitamins E and C
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Najlae El Kertaoui Carmen María Hernández‐Cruz Daniel Montero María José Caballero Reda Saleh Juan Manuel Afonso Marisol Izquierdo 《Aquaculture Research》2017,48(2):419-433
Despite the interest of meagre (Argyrosomus regius) as a fast‐growing candidate for Mediterranean aquaculture diversification, there is a lack of information on nutrition along larval development. Importance of highly unsaturated fatty acids (HUFA) and the antioxidant vitamins E and vitamin C has not been investigated yet in this species. Six diets with two levels of HUFA (0.4% and 3% dw), two of vitamin E (1500 and 3000 mg kg?1) and two of vitamin C (1800 and 3600 mg kg?1) were fed to 15 dah meagre larvae. Larval growth in total length and dry body weight was significantly lowest in larvae fed diet 0.4/150/180 and showed few lipid droplets in enterocytes and hepatocytes and lower HUFA contents than the initial larvae. Increase in dietary HUFA up to 3%, significantly improved larval growth and lipid absorption and deposition. Besides, among fish fed 3% HUFA, increase in vitamin E and vitamin C significantly improved body weight, as well as total lipid, 22:6n‐3 and n‐3 fatty acids contents in the larvae. Thus, the results showed that 0.4% dietary HUFA is not enough to cover the essential fatty acid requirements of larval meagre and a high HUFA requirement in weaning diets is foreseen for this species. Besides, the results also pointed out the importance of dietary vitamin E and C to protect these essential fatty acids from oxidation, increase their contents in the larvae and promote growth, suggesting high vitamin E and C requirements in meagre larvae (higher than 1500 and 1800 mg kg?1 for vitamin E and vitamin C respectively). 相似文献
72.
Samir Afram Michael Abdel Hai El Refaii N. McHardy D. G. Rae 《Tropical animal health and production》1989,21(4):218-222
Summary Chronic, undulatingTheileria annulata infection was diagnosed as the cause of severely depressed milk yields in a herd of 44 Friesian cows in Egypt. The herd was divided at random into two groups of 22; one group was injected intramuscularly with a single dose of the experimental antitheilerial drug, buparvaquone, while the other remained untreated. Over the subsequent seven weeks milk yield in the treated group increased to double that of the untreated group (P<0.05). Pyrexia was controlled within two days of injection of buparvaquone and piroplasm parasitaemia was eliminated in one week. It is suggested that treatment of dairy cattle chronically infected withT. annulata using buparvaquone may have the dual beneficial effect of reducing the pathogenic effects of theileriosis, thereby permitting restoration of an impaired immune system, thus increasing resistance to other infections. If a similar effect could be produced inBos indicus cattle inT. annulata endemic areas, treatment of indigenous cattle with buparvaquone could be a useful alternative to the introduction ofBos taurus blood as a way of boosting milk production.
Efecto Sobre La Produccion De Leche Del Tratamiento De La Theileriosis Cronica Con Buparvaquone
Resumen Se diagnosticó infección crónica ondulate deTheileria annulata, en un hato de 44 vacas Friesian en Egipto; la causa fue, la caida severa de la producción láctea. Se dividió el hato al azár, en dos grupos de 22 vacas cada uno; un grupo se inyectó via intramuscular, con una dosis única de la droga experimental buparvaquone y el otro no se trató. Durante las siete semanas subsiguientes, la producción láctea aumentó el doble en el grupo tratado, en relación con el grupo sin tratar (P<0.05). La pirexia fue controlada, dentro de los dos primeros dias después de la inyección de buparvaquone, y la parasitemia por piroplasmas se eliminó en una semana. Se sugiere, que el tratamiento con buparvaquone del genado de leche infectado crónicamente conT. annulata, podría tener doble efecto benéfico, al reducir el efecto patógeno de la theileriosis, permitiendo la restauración del sistema inmunológico, incrementando así la resistencia a otras infecciones. Si un efecto similar se produjera en ganadoBos indicus, en áreas endémicas deT. annulata, el tratamiento del ganado nativo con buparvaquone, podría convertirse en una alternativa a la introducción de sangreBos taurus, para incrementar la producción láctea.
Effet Du Traitement De La Theileriose Chronique Par La Buparvaquone Sur Les Rendements Laitiers
Résumé L'infection chronique et à rechutes àTheileria annulata a été diagnostiquée comme étant la cause de rendements laitiers fortement déprimés dans un troupeau de 44 vaches frisonnes en Egypte. Le troupeau fut partagé, au hasard, en deux groupes de 22; un groupe a reçu par voie intramusculaire, une dose unique d'un médicament antitheileriose expériemental, la buparvaquone, tandis que l'autre n'était pas traité. Pendant les sept semaines suivantes, le rendement laitier du groupe traité a doublé par rapport à celui du groupe non triaté (P<0.05). L'hyperthermie a été contrôlée dans les deux jours suivant l'injection de buparvaquone, et la parantémie à piroplasme éliminée en une semaine. Il est suggéré que le traitement du bétail laitier chroniquement infecté parT. annulata à l'aide de la buparvaquone peut avoir le double effet bénéfique de réduire les effects pathologiques de la theilériose, permettant ainsi la restauration d'un système immunitaire affaibli, ce qui augmente la résistance aux autres infections. Si un effet similaire pouvait être produit chez le bétailBos indicus des régions à endémicitéT annulata, le traitement du bétail indigène avec la buparvaquone pourrait être une alternative utile à l'introduction du sangBos taurus dans le but de stimuler la production laitière.相似文献
73.
74.
75.
Studies on the Physiological Chemistry of the Tibio-Tarsal Synovial Fluid of Healthy Bovines
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S. El. Amrousi M. K. Soliman L. B. Youssef 《Canadian journal of veterinary research》1966,30(9):251-255
The physical properties, chemical composition and cytological content of the synovial fluid of healthy native breed cattle, obtained by tibio-tarsal arthrocentesis, was studied. 相似文献
76.
A.?El HadramiEmail author D.?Kone P.?Lepoivre 《European journal of plant pathology / European Foundation for Plant Pathology》2005,113(3):241-254
The black leaf streak disease (BLSD), caused by Mycosphaerella fijiensis, is the most destructive disease of bananas and plantains around the world. Breeding for resistance is the most promising
strategy to fight this disease especially in small farmer plantations. Mycosphaerella fijiensis produces many phytotoxins such as juglone, which can be used, jointly with field and inoculations under controlled conditions,
for screening banana cultivars for BLSD-resistance. This non-host specific phytotoxin has been shown to act on chloroplasts
and disturbs the proton electrochemical gradient across the plasmalemma membrane. Moreover, an involvement of the oxidative
burst during the interaction has been suggested. The present study was carried out using two cultivars that differed for either
their juglone-responses or their resistance to BLSD (cv. Grande Naine susceptible to BLSD and juglone and cv. Fougamou partially
resistant to BLSD and highly tolerant to juglone). The production of active oxygen species (AOS) and the enhancement of the
enzymatic and/or non-enzymatic AOS-scavenging systems were investigated after treatment of the two cultivars with juglone.
The time-course of AOS-production and AOS-scavenging was shown to be the key difference between these two tested cultivars
after treatment with juglone. Thus, an early release of AOS (O2− radical and H2O2) and a quick stimulation of a preferment anti-oxidant system (superoxide dismutases, catalases, and peroxidases) was observed
for cv. Fougamou as compared to cv. Grande Naine for which a late and weak generation of AOS accompanied by a late stimulation
of the anti-oxidant systems were detected. 相似文献
77.
78.
S. M. El Hassan M. S. M. A. Harbi M. I. Abu Bakr 《Veterinary research communications》1984,8(1):65-67
Goats that had been inoculated with the causal organism of contagious, caprine pleuropneumonia and treated, within a few days, with oxytetracycline or tylosin, were less severely affected than infected, untreated control goats. However, 20% of treated cases remained infective and were, presumably, capable of transmitting the infection. 相似文献
79.
Gutiérrez-Martín CB del Blanco NG Blanco M Navas J Rodríguez-Ferri EF 《Veterinary microbiology》2006,115(1-3):218-222
A total of 229 Spanish Actinobacillus pleuropneumoniae isolates recovered from diseased pigs with pleuropneumonia from 1997 to 2004 was tested for their susceptibility to 11 antimicrobials in a broth microdilution method. All the isolates were susceptible to florfenicol and most of them to cephalothin; however, a high rate of resistance was observed to tetracycline. A bimodal or multimodal distribution of isolates over the MIC range were observed for penicillins, tetracycline, trimethoprim, sulfisoxazole and nalidixic acid, suggesting the development of acquired resistance. Eight resistance patterns were established, and 21.1% of the isolates were resistant to at least two antimicrobials. In addition, a considerable increase in the resistance to tetracyclines was observed during the last decade in Spain, when compared with other A. pleuropneumoniae strains isolated during 1987-1988 (Gutiérrez, C.B., Píriz, S., Vadillo, S., Rodríguez Ferri, E.F., 1993. In vitro susceptibility of Actinobacillus pleuropneumoniae strains to 42 antimicrobial agents. Am. J. Vet. Res. 54, 546-550); this finding was also observed for gentamicin in minor percentage. 相似文献
80.
del Río ML Navas J Martín AJ Gutiérrez CB Rodríguez-Barbosa JI Rodríguez Ferri EF 《Veterinary research》2006,37(1):49-59
Bacteria have evolved a set of highly specialized proteins to capture iron in iron-depleted environments. The acquisition and uptake of iron present in the extracellular milieu of eukaryotic organisms is indispensable for the growth and survival of microbial pathogens in the course of infection. Haemophilus parasuis is the causative agent of Gl?sser disease, which is responsible for considerable financial losses in pig-rearing worldwide. To gain insight into the mechanisms involved in siderophore-mediated iron uptake in H. parasuis, genes in the H. parasuis ferric hydroxamate uptake (Fhu) region were amplified in the work being reported here. As has been described in A. pleuropneumoniae, an Fhu genomic region was also present in H. parasuis, being composed of four potential consecutive open reading frames (ORF) designated as fhuC, fhuD, fhuB, and fhuA, respectively. By immunoblotting, using a cross-reactive polyclonal antibody raised against Actinobacillus pleuropneumoniae FhuA protein, it was demonstrated that this protein was constitutively expressed in H. parasuis and its level of expression was not modified under conditions of restricted iron availability. This is the first report describing the presence of the fhu genes in H. parasuis. Our results indicate that FhuA protein expression is not affected under iron-restricted conditions, however, it is one of the targets of the humoral immune response. 相似文献