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1.
Douglas Tave Mahmoud Rezk R. Oneal Smitherman 《Journal of the World Aquaculture Society》1989,20(4):214-222
Gold, bronze, and black (normal pigmentation) body colors in Tilapia mossambica are controlled by a single autosomal gene with incomplete dominant gene action: GG fish are black gg fish are gold; Gg fish are bronze. Because gold body color is produced by the recessive genotype, it is easy to produce and to maintain a truebreeding population of gold T. mossambica for commercial purposes. If all other colors are culled, the population will breed true, because gold × gold will always produce 100% gold offspring. The G gene will be a valuable genetic marker for many genetic studies, such as the production of gynogenetic T. mossambica . 相似文献
2.
Heba S. A. Taha Sameh A. Abdelnour Mahmoud Alagawany 《Journal of animal physiology and animal nutrition》2019,103(3):747-755
Heavy metals have enormous variety of deleterious effects on many organs in the body. This study demonstrated the toxic influences of lead on the growth, biochemical, cellular and molecular aspects of developing rabbits. Seventy‐five rabbits (New Zealand NZW) were divided into five equal groups as follows; control (C) and four treatment groups (T1‐4) orally administered lead acetate solution as follow T1: 20, T2: 30, T3: 50 and T4: 70 mg/kg body weight. Lead resulted in a significant decrease in live body weight, daily body weight gain and feed intake in T3 and T4 compared to those in other groups. Blood haematology measurements such as red blood cells, haematocrit (HCT), mean corpuscular volume, platelet, white blood cells and lymphocytes were significantly influenced by the high level of lead. Oral administration of lead significantly reduced total proteins in the serum. It was observed that the high lead level led to significantly (p < 0.05) increased levels of aspartate aminotransferase, alanine aminotransferase enzymes, urea and creatinine. Four random amplified polymorphic DNA primers polymorphism were detected among the treatment groups. Total number of induced bands (loss or appearance) compared with control group were 4, 10, 10 and 14 bands using primers P1, P2, P3 and P4 respectively. Number of micronuclei showed a dose–response increase and the difference was highly significant especially between control compared with T3 and T4 groups. From our results, we can conclude that exposure of rabbits to lead acetate resulted in negative effects on the growth performance and altered the haematological and biochemical parameters, in addition to its adverse impact on cytological and molecular characterization of animals. 相似文献
3.
Abdel-Hamid Tamer M. El-Tarabany Mahmoud S. 《Tropical animal health and production》2019,51(8):2421-2429
Tropical Animal Health and Production - The aim was to evaluate the effect of bee pollen (BP) on performance, blood parameters, and metabolic hormones in New Zealand White (NZW) and Rex (RX)... 相似文献
4.
Mahmoud A.O. Dawood Mahmoud S. Gewaily Ali A. Soliman Mustafa Shukry Asem A. Amer Elsayed M. Younis Abdel-Wahab A. Abdel-Warith Hien Van Doan Adel H. Saad Mohamed Aboubakr Hany M.R. Abdel-Latif Sabreen E. Fadl 《Marine drugs》2020,18(12)
Marine-derived substances are known for their beneficial influences on aquatic animals’ performances and are recommended to improve intestinal health, immunity, and anti-oxidative status. The present study investigates the role of chitosan nanoparticles on the intestinal histo-morphometrical features in association with the health and immune response of Grey Mullet (Liza ramada). Chitosan nanoparticles are included in the diets at 0, 0.5, 1, and 2 g/kg and introduced to fish in a successive feeding trial for eight weeks. The final body weight (FBW), weight gain (WG), and specific growth rate (SGR) parameters are significantly increased while feed conversion ratio (FCR) decreases by chitosan nanoparticles compared to the control (p < 0.05). The morphometric analysis of the intestines reveals a significant improvement in villus height, villus width, and the number of goblet cells in chitosan-treated groups in a dose-dependent manner. Additionally, there is a positive correlation between the thickness of the enterocyte brush border and the chitosan dose, referring to an increasing absorptive activity. Histologically, the intestinal wall of Grey Mullet consists of four layers; mucosa, sub-mucosa, tunica muscularis (muscular layers), and serosa. The histological examination of the L. ramada intestine shows a normal histo-morphology. The epithelial layer of intestinal mucosa is thrown into elongated finger-like projections, the intestinal villi. The values of hemoglobin, hematocrit, red blood cells (RBCs), total protein (TP), albumin, and globulin are significantly increased in fish fed 1, and 2 g/kg of chitosan nanoparticles compared to fish fed 0 and 0.5 g/kg (p < 0.05). The highest levels of TP and albumin are observed in fish fed 1 g/kg diet (p < 0.05). The lysozyme activity and phagocytic index are significantly enhanced by feeding chitosan nanoparticles at 0.5, 1, and 2 g/kg, whereas the phagocytic activity is improved in fish fed 1 and 2 g/kg (p < 0.05). The highest lysozyme activity and phagocytic index are observed in fish fed 1 g/kg. SOD is significantly activated by feeding chitosan nanoparticles at 1 g/kg. Simultaneously, glutathione peroxidase (GPx) and catalase (CAT) activities also are enhanced by feeding chitosan at 1 and 2 g/kg, compared to fish fed 0 and 0.5 g/kg (p < 0.05). The highest GPx and CAT activities are observed in fish fed 1 g/kg (p < 0.05). Conversely, the malondialdehyde (MDA) levels are decreased by feeding chitosan at 1 and 2 g/kg, with the lowest being in fish fed 1 g/kg (p < 0.05). To summarize, the results elucidate that L. ramada fed dietary chitosan nanoparticles have a marked growth rate, immune response, and anti-oxidative response. These improvements are attributed to the potential role of chitosan nanoparticles in enhancing intestinal histo-morphometry and intestinal health. These results soundly support the possibility of using chitosan nanoparticles at 1–2 g/kg as a feasible functional supplement for aquatic animals. 相似文献
5.
6.
In addition to luteolin and its 7-methyl ether, the CH2Cl2-MeOH (1:1) extract of Cyperus conglomeratus afforded two new prenylflavans identified as 7,3'-dihydroxy-5,5'-dimethoxy-8-prenylflavan and 5,7,3'-trihydroxy-5'-methoxy-8-prenylflavan. The structures were established by CIMS, 1H-NMR, 13C-NMR, H-H COSY, HMQC, HMBC and DEPT analysis. 相似文献
7.
Beet cyst nematodes (BCN, Heterodera schachtii), Cercospora beticola, and rhizomania, caused by the beet necrotic yellow vein
virus (BNYVV) and vectored by the soil-borne fungus Polymyxa betae, are the most serious diseases of sugar beet ( Beta vulgaris
subsp. vulgaris). The wild Beta species of section Procumbentes are known to be completely resistant to H. schachtii, C. beticola
and P. betae. Alien monosomic additions (2n=19), plants of cultivated beet (2n=18) carrying different individual chromosomes
of B. procumbens (2n=18) or B. patellaris (2n=36), were tested in greenhouse experiments for resistance to these pathogens.
Gene(s) conferring full resistance to the beet cyst nematode in B. patellaris are located on chromosome 1.1, and the other
tested chromosomes of B. patellaris are not involved in the expression of resistance. Artificial inoculation under greenhouse
conditions, with in vitro produced inoculum of C. beticola and spot-percentage rating of the disease intensity, showed that
the high level of resistance that was observed in the wild species B. procumbens and B. patellaris was not found in any of
the monosomic additions tested. It was suggested that genes on various chromosomes of the wild species are needed to express
full resistance, and that the chromosomes of group 7 of B. patellaris and chromosome 7 of B. procumbens have the largest effect.
The greenhouse tests for resistance to P. betae in B. patellaris derived monosomic additions showed that the addition families
of group 4.1 have a strong partial resistance, while the addition families of group 8.1 appeared to be completely resistant
to the pathogen. Resistance to P. betae in the two wild species as well as in the two resistant addition types did not exclude
infection with BNYVV, but resulted in a considerable reduction of the virus concentration. It was concluded that resistance
to the vector would complement virus resistance, and may provide a more effective and durable control of rhizomania.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
Bluetongue virus type 16, isolated from sheep in Egypt, was injected to 4 normally cycling Barki ewes and caused high levels of inhibin. This was assayed by a biological method, using suppression of the luteinising hormone (LH) of castrated rats. Albumin (fraction 2) was injected to normally cycling ewes. The sera of injected ewes were investigated 1 day after injection and weekly up to the 4th one injection. There was a gradual decrease of LH (4.8 +/- 0.52 I.U./ml serum) until the minimum level (1.17 +/- 0.25 I.U./ml serum) was reached, in comparison to the control serum LH which was 5.26 +/- 0.52 I.U./ml serum during the dioestrous phase. 相似文献
9.
10.
Elfaki MG Abbas B Mahmoud OM Kleven SH 《Comparative immunology, microbiology and infectious diseases》2002,25(1):49-57
Post-mortem examinations of 100 camels with pneumonic lesions were made at a local abattoir for Mycoplasma species. Sixteen isolates with indistinguishable biochemical and immunological characters were identified. The biochemical profile of these isolates showed that they were sensitive to digitonin, negative for urease production, glucose fermentation, and phosphatase activity but were positive for arginine hydrolysis. The identity of these isolates was further confirmed by disk growth inhibition test using a panel of specific antisera against selected reference Mycoplasma spp. Based on the biochemical profile and growth inhibition results, the camel isolates were identified as M. arginini. The pathological findings associated with M. arginini isolation consisted mostly of chronic interstitial pneumonia. The isolation rate of M. arginini from these specimens was 8.8%. These results suggest that the role of M. arginini in pneumonia in camels should be explored in greater detail. 相似文献