Biochemical Changes in Freshwater Prawn Macrobrachium rosenbergii During Larval Development     

Paymon  Roustaian Mohd Salleh  Kamarudin Hishamuddin Bin  Omar Che Roos  Saad Mansor Haji  Ahmad 《Journal of the World Aquaculture Society》2001,32(1):53-59

Abstract.— Quantitative changes in the protein, lipid and carbohydrate were studied in the early larval stages of developing freshwater prawn Macrobrachium rosenbergii reared under fed and starved conditions to understand the relative importance of these nutrients in energy metabolism of the growing larvae. Larvae obtained from several females were stocked into three 250-L tanks at a density of 30 larvae/L. The feeding regime consisted of newly hatched Artemia nauplii. Protein was always the major organic constituent followed by lipids and then carbohydrates of both fed and starved larvae. Protein levels of both fed and starved larvae increased during development, suggesting an important role in morphogenesis. The decline of lipid during the larval growth that was more rapid for starved larvae, suggests a probable utilization of lipid as the major metabolic source of energy. Carbohydrates formed less than 5 and 2.4% of the larval dry weight of fed and starved larvae, respectively, suggesting their limited role in larval metabolism.  相似文献   

Characterization of sumac (Rhus tripartitum) root barks tannin for a potential use in wood adhesives formulation     

S. Ben Mahmoud  H. Saad  B. Charrier  A. Pizzi  K. Rode  N. Ayed  F. Charrier-El Bouhtoury 《Wood Science and Technology》2015,49(1):205-221

  相似文献   

Characterization of a Probiotic Lactobacillus fermentum Isolated from Snakehead,Channa striatus,Stomach     

Sayed K. Allameh  Fatimah M. Yusoff  Hassan M. Daud  Einar Ringø  Aini Ideris  Che R. Saad 《Journal of the World Aquaculture Society》2013,44(6):835-844

This study sought to isolate and characterize lactic acid bacteria (LAB) from stomach of adult snakehead fish, Channa striatus, to be used as probiotics for freshwater fish. A total of 13 strains were isolated from the stomach of 10 fish, and 4 of these belonged to LAB. Strain LAB‐3 showing highest in vitro growth inhibition of Aeromonas hydrophila in a disk diffusion test was identified as Lactobacillus fermentum by conventional and molecular techniques and evaluated in vitro through various tests. The bacterium could grow at pH 3–8; but the optimum growth was observed at pH 6. Moreover, LAB‐3 grew at 0.15 and 0.3% bile salt concentrations, from 15 to 45 C, and at 4% NaCl. L. fermentum showed in vitro inhibitory activity against three fish pathogens, A. hydrophila, Pseudomonas aeruginosa, and Shewanella putrefaciens, tested by disk diffusion and well diffusion methods. Antibiotic sensitivity tests indicated that L. fermentum was resistant to streptomycin, gentamycin, and kanamycin, intermediate to tetracycline, but sensitive to chloramphenicol, amoxicillin, and ampicillin. Challenge test by using A. hydrophila showed that survival of snakehead was significantly (P < 0.05) improved when 2 × 10⁶ LAB‐3/g was supplemented to the diet. Therefore, this study suggests that L. fermentum might be a promising probiotic in snakehead aquaculture .  相似文献   

Influence of thiosulfate on nitrification,denitrification, and production of nitric oxide and nitrous oxide in soil     

O. A. L. O. Saad  S. Lehmann  R. Conrad 《Biology and Fertility of Soils》1996,21(3):152-159

Thiosulfate and CS₂ inhibit nitrification. The effect of the addition of thiosulfate on the turnover of inorganic N compounds was tested in an Egyptian and a German arable soil under nitrifying and denitrifying conditions. For nitrification, the soils were amended with NH _inf4 ^sup+ and incubated under aerobic conditions. For denitrification, the soils were amended with NO _inf3 ^sup- and incubated under anaerobic conditions. In both cases, the thiosulfate decreased with time while tetrathionate accumulated to an intermediate extent. Both compounds disappeared completely after <25 days. Production of CS₂ was not observed. Carbonyl sulfide was produced only in the Egyptian soil, but production decreased with increasing amounts of added thiosulfate. Under nitrifying conditions, the addition of increasing amounts of thiosulfate (25, 50, and 100 g S g^-1 dry weight) resulted in decreasing rates of NH _inf4 ^sup+ oxidation to NO _inf3 ^sup- ; it also resulted in an increasing intermediate accumulation of NO _inf2 ^sup- and NO, and in an increasing production of N₂O. Under denitrifying conditions, the addition of increasing amounts of thiosulfate did not significantly affect the rate of NO _inf3 ^sup- reduction, and resulted in an increasing intermediate accumulation of NO _inf2 ^sup- and of NO only in the German soil in which the production of N₂O was slightly inhibited by thiosulfate. These results demonstrate that the nitrification of NH _inf4 ^sup+ and NO _inf2 ^sup- was inhibited by increasing concentrations of thiosulfate and/or tetrathionate without involving the formation of volatile S compounds as potential nitrification inhibitors. Denitrification was not affected by the addition of thiosulfate.  相似文献   

Evaluation of combined Pasteurella vaccines in control of sheep pneumonia     

S Chandrasekaran  K Hizat  Z Saad  M Y Johara  P C Yeap 《The British veterinary journal》1991,147(5):437-443

The effectiveness of an oil adjuvant vaccine (OAV) incorporating locally isolated strains of Pasteurella haemolytica type 7 and Pasteurella multocida types A and D was compared with that of Carovax (Wellcome Laboratories) in imported cross-bred lambs. The criterion of efficacy was the ability of the vaccines to reduce the extent of pneumonic lesions in vaccinated as against unvaccinated control lambs. The OAV produced at this Institute significantly reduced the lung lesions at P less than 0.05 level compared with its control group when challenged with P. haemolytica alone. However, the vaccine was unsatisfactory against P. multocida or combined P. multocida P. haemolytica challenge. Carovax did not produce any significant reduction in the lung lesions caused by P. haemolytica and/or P. multocida.  相似文献   

The Effect of Pasteurella haemolytica A2 Infection on Phagocytosis Efficiency of Caprine Broncho‐Alveolar Macrophages     

M. Zamri‐Saad  H. R. Mera 《Zoonoses and public health》2001,48(7):513-518

An experiment was designed to study the in vivo effect of Pasteurella haemolytica A2 infection on the phagocytosis activity of caprine broncho‐alveolar macrophages and the extent of pneumonic lesions. Twelve healthy local Kacang goats, about 7 months of age, were divided into two groups of six. Goats in group 1 were inoculated intratracheally with 4 ml inoculum containing 2.8 × 10⁹ colony‐forming units (CFU)/ml of Staphylococcus aureus. Goats in group 2 were inoculated intratracheally with 4 ml of inoculum containing 9.5 × 10⁸ CFU/ml of Pasteurella haemolytica A2 isolated earlier from pneumonic lungs of goat. At intervals of 3 and 7 days post‐challenge five goats from each group were killed and the lungs were washed with sterile phosphate‐buffered saline. Smears were prepared from the lung washing fluid and the number of macrophages with phagocytic activity was determined. At day 3 post‐infection, goats of both groups showed a similar pattern of pneumonic lesion. The lung washing fluid of goats in group 2 was found to contain numerous neutrophils and macrophages. Goats in group 2 showed significantly (P < 0.05) higher extent of lung lesions than group 1. Similarly, the average extent of lung lesions was significantly (P < 0.05) more severe in group 2 at day 7 post‐infection. The lung washing fluid contained mostly macrophages. The phagocytic activity following S. aureus infection was more efficient and significantly (P < 0.01) higher compared with infection by P. haemolytica A2. There were weak correlations between the extent of pneumonic lesion and the phagocytic activity. Thus, goats with poor phagocytic activity were likely to develop more extensive lung lesions.  相似文献   

Implementation of herd health program to improve survival of Boer goats in Malaysia     

Salisi MS  Saad MZ  Kasim A 《Tropical animal health and production》2012,44(2):207-211

A Boer goat breeding farm with 800 heads of breeder females, 50 breeder males, and 400 growing goats of various ages in Sabah, Malaysia was selected to study the effect of implementing herd health program. This included vaccination program against pneumonic mannheimiosis; fecal monitoring for helminthiasis, coccidiosis, and colibacillosis; and introduction of modified feeding regime comprised of day-time grazing and feeding of cut grass and supplemented feed. The herd health program was implemented in September 2007 and the impact was observed on body weight gains, body scoring, and annual mortality among adults and kids. It was found that implementation of herd health program significantly (p < 0.05) increased the average body weight gains in both adults and kids from 1.8 g per kid and 0.6 g per adult in 2006 to 3.7 g per kid and 2.2 g per adult in 2008. The percentage of adults with body scoring of <3 was significantly (p < 0.05) reduced from 82.3% in 2006 to 77.6% in 2007 and 4% in 2008. Similarly, the annual mortality rate was significantly (p < 0.05) reduced from 6.5% among kids and 58.2% among adults in 2006 to 12.1% among kids and 10.4% among adults in 2007, and to 9.1% among kids and 1.1% among adults in 2008. Therefore, it was concluded that implementation of herd health program significantly improved the survival and performance of goats.  相似文献   

Current experimental models,assessment and dietary modulations of intestinal permeability in broiler chickens     

Saad Gilani  Peter V. Chrystal  Reza Barekatain 《动物营养（英文）》2021,7(3):801-811

Maintaining and optimising the intestinal barrier (IB) function in poultry has important implications for the health and performance of the birds. As a key aspect of the IB, intestinal permeability (IP) is mainly controlled by complex junctional proteins called tight junction proteins (TJ) that link enterocytes together. The disruption of TJ is associated with increased gut leakage with possible subsequent implications for bacterial translocation, intestinal inflammation, compromised health and performance of the birds. Despite considerable data being available for other species, research on IP in broiler chickens and in general avian species is still an understudied topic. This paper reviews the available literature with a specific focus on IP in broiler chickens with consideration given to practical factors affecting the IP, current assessment methods, markers and nutritional modulation of IP. Several experimental models to induce gut leakage are discussed including pathogens, rye-based diets, feed deprivation and stress-inducing agents such as exogenous glucocorticoids and heat stress. Although various markers including fluorescein isothiocyanate dextran, expression of TJ and bacterial translocation have been widely utilized to study IP, recent studies have identified a number of excreta biomarkers to evaluate intestinal integrity, in particular non-invasive IP. Although the research on various nutrients and feed additives to potentially modulate IP is still at an early stage, the most promising outcomes are anticipated for probiotics, prebiotics, amino acids and those feed ingredients, nutrients and additives with anti-inflammatory properties. Considerable research gaps are identified for the mechanistic mode of action of various nutrients to influence IP under different experimental models. The modulation of IP through various strategies (i.e. nutritional manipulation of diet) may be regarded as a new frontier for disease prevention and improving the health and performance of poultry particularly in an antibiotic-free production system.  相似文献   

Sedative and cardiopulmonary effects of medetomidine hydrochloride and xylazine hydrochloride and their reversal with atipamezole hydrochloride in calves     

Rioja E  Kerr CL  Enouri SS  McDonell WN 《American journal of veterinary research》2008,69(3):319-329

OBJECTIVE: To assess the sedative and cardiopulmonary effects of medetomidine and xylazine and their reversal with atipamezole in calves. ANIMALS: 25 calves. PROCEDURES: A 2-phase (7-day interval) study was performed. Sedative characteristics (phase I) and cardiopulmonary effects (phase II) of medetomidine hydrochloride and xylazine hydrochloride administration followed by atipamezole hydrochloride administration were evaluated. In both phases, calves were randomly allocated to receive 1 of 4 treatments IV: medetomidine (0.03 mg/kg) followed by atipamezole (0.1 mg/kg; n = 6), xylazine (0.3 mg/kg) followed by atipamezole (0.04 mg/kg; 7), medetomidine (0.03 mg/kg) followed by saline (0.9% NaCl; 6) solution (10 mL), and xylazine (0.3 mg/kg) followed by saline solution (10 mL; 6). Atipamezole or saline solution was administered 20 minutes after the first injection. Cardiopulmonary variables were recorded at intervals for 35 minutes after medetomidine or xylazine administration. RESULTS: At the doses evaluated, xylazine and medetomidine induced a similar degree of sedation in calves; however, the duration of medetomidine-associated sedation was longer. Compared with pretreatment values, heart rate, cardiac index, and PaO(2) decreased, whereas central venous pressure, PaCO(2), and pulmonary artery pressures increased with medetomidine or xylazine. Systemic arterial blood pressures and vascular resistance increased with medetomidine and decreased with xylazine. Atipamezole reversed the sedative and most of the cardiopulmonary effects of both drugs. CONCLUSIONS AND CLINICAL RELEVANCE: At these doses, xylazine and medetomidine induced similar degrees of sedation and cardiopulmonary depression in calves, although medetomidine administration resulted in increases in systemic arterial blood pressures. Atipamezole effectively reversed medetomidine- and xylazine-associated sedative and cardiopulmonary effects in calves.  相似文献   

Pathogenicity of an avian influenza virus serotype H9N2 in chickens     

Gharaibeh S 《Avian diseases》2008,52(1):106-110

A low pathogenic avian influenza virus (AIV) serotype H9N2 affected many commercial flocks in the Middle East in late 1990s and early 2000s. Due to the varying pathogenicity ofAIV H9N2 reported in previous studies, this study was carried out to determine the pathogenicity of a Jordanian isolate of H9N2 in broiler and specific-pathogen-free (SPF) chickens. Mild tracheal rales were observed in the broilers but not in the SPF birds starting 3 days postinfection (DPI) and until the end of the experiment at 16 DPI. Infected chickens had gross and histologic changes limited to the respiratory system (sinuses, trachea, lungs, and air sacs) characterized by congestion and lymphoplasmacytic inflammation. However, the lesions in the broiler chickens were more severe than those in the SPF chicks. Furthermore, the virus caused significant (P = 0.004) reduction (230 g) in average body weight of the infected broiler group compared with the uninfected broiler group. Both broiler and SPF-infected groups seroconverted, and they had a geometric mean titer of 2(8.2) and 2(9.3), respectively, on the hemagglutination inhibition test at 16 DPI. Cloacal virus shedding was not detected by 9 DPI and 15 DPI in broiler and SPF-infected groups, respectively. This study demonstrated the pathogenic nature of the local Jordanian H9N2 isolate and the variation from what it has been reported in other countries of the region. Regional effort should be directed to start an eradication program of this disease because of its pathogenicity for chickens, wide distribution, and possible interference with surveillance for H5N1 serotype.  相似文献