Genetics of Body Color in Tilapia mossambica

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 .     

Marine-Derived Chitosan Nanoparticles Improved the Intestinal Histo-Morphometrical Features in Association with the Health and Immune Response of Grey Mullet (Liza ramada)

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.     

Nutritional significance of amino acids,vitamins and minerals as nutraceuticals in poultry production and health – a comprehensive review

Nutraceuticals have gained immense importance in poultry science recently considering the nutritional and beneficial health effects of their constituents. Besides providing nutritional requirements to birds, nutraceuticals have beneficial pharmacological effects, for example, they help in establishing normal physiological health status, prevent diseases and thereby improve production performance. Nutraceuticals include amino acids, vitamins, minerals, enzymes, etc. which are important for preventing oxidative stress, regulating the immune response and maintaining normal physiological, biochemical and homeostatic mechanisms. Nutraceuticals help in supplying nutrients in balanced amounts for supporting the optimal growth performance in modern poultry flocks, and as a dietary supplement can reduce the use of antibiotics. The application of antibiotic growth enhancers in poultry leads to the propagation of antibiotic-resistant microbes and drug residues; therefore, they have been restricted in many countries. Thus, there is a demand for natural feed additives that lead to the same growth enhancement without affecting the health. Nutraceuticals substances have an essential role in the development of the animals’ normal physiological functions and in protecting them against infectious diseases. In this review, the uses of amino acids, vitamins and minerals as well as their mode of action in growth promotion and elevation of immune system are discussed.     

Heavy Metal Immobilization in Contaminated Soils using Phosphogypsum and Rice Straw Compost

The application of soil amendments to immobilize heavy metals is a promising technology to meet the requirements for environmentally sound and cost‐effective remediation. The present study was carried out to evaluate the result of phosphogypsum (PG) used alone and in combination with compost (CP) at a mix ratio of 1:1 wet weight ratio (PG + CP) at 10 and 20 g dry weight kg⁻¹ dry soil, on heavy metal immobilization in contaminated soil and on canola growth. The results revealed that the Pb, Cd and Zn uptake of canola plants was reduced by the application of PG alone and when it was mixed with CP as compared with untreated soil. At an application rate of 10 g dry weight kg⁻¹ dry soil of (PG + CP) the dry weight of canola plants increased by 66·8% was increased in comparison with its weight in the untreated soil. The addition of PG alone resulted in more pronounced immobilization of heavy metal as compared with PG mixed with CP. Plant growth was improved with CP addition, but heavy metals immobilization was the greatest in PG alone treatments. Results suggest that PG may be useful for the immobilization of heavy metals in contaminated soils. Copyright © 2014 John Wiley & Sons, Ltd.     

Isolation and characterization of Mycoplasma arginini from camels (Camelus dromedarius) with pneumonia

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.     

Detection of Brucella species in the milk of infected cattle,sheep, goats and camels by PCR

One hundred and three milk samples were collected from 52 cows, 21 ewes, 18 goats and 12 camels. The animals tested positive to at least one of the following: (1) standard tube agglutination test (SAT); (2) Rose Bengal plate test (RBPT); (3) milk ring test (MRT). All milk samples were examined by culture and single-step polymerase chain reaction (PCR) techniques for detection of Brucella species. The PCR assay amplified Brucella-DNA from 29 bovine milk samples, 10 from sheep, 13 from goats and one from a camel. The direct culture method detected Brucella organisms from 24 samples of cows' milk, 12 from sheep, 10 from goats and failed to detect any Brucella organisms from camels' milk. PCR detected up to 100 colony forming units (CFU) of B. abortus per millilitre of milk in 100% of diluted milk samples, and 1000 CFU of B. melitensis from 70% of milk samples. Although the overall sensitivity of the PCR was higher than the culture method, it should be possible to increase the sensitivity to detect lower numbers of Brucella organisms in field samples. The speed and sensitivity of the PCR assay suggest that this technique could be useful for detection of Brucella organisms in bovine milk, as well as in sheep, goat, and camels milk.     

Molecular based assessment of genetic diversity within Barbary fig (Opuntia ficus indica (L.) Mill.) in Tunisia

In this work, we report for the first time on the analysis of genetic diversity within a set of 36 Tunisian Opuntia ficus indica (L.) Mill. ecotypes using RAPD markers.     

Fruit and seed diversity of domesticated carob (Ceratonia siliqua L.) in Morocco

The carob tree (Ceratonia siliqua L.) is an important economic resource for Morocco's rural populations. This species is used in reforestation actions and its cultivation in modern orchards is being undertaken to valorize marginal lands and substitute for drought sensitive species. However, little data is available on its intra-specific variability and its adaptability. Morphological characters of pods and seeds from 13 ecoregions of private-domesticated carob were used to assess phenotypic variation of this species. These stands extend from south-west to north-east and cover a wide range of Morocco's ecoregions. Pods length, width, thickness, seeds number, pulp weight, seeds yield and seeds length, width, thickness and weight were measured for 390 trees (30 trees per ecoregion). Statistically significant differences were found between ecoregions for all characters which were examined, what indicates a high phenotypic diversity. Principal component analysis (PCA) and hierarchical cluster of all ecoregions lead to identify two major and opposite groups (the northern ecoregions; and the central and south-western ecoregions). Ecoregions of the north of Morocco exhibited the largest and the thickest pods with the highest pulp weight while other ecoregions have relatively short pods but largest proportion of seed yield. Similarly, the northern ecoregions are characterized by the heaviest seeds. A correlation matrix between morphological characters, geographic parameters and precipitation exhibits a positive and a negative correlation of pods thickness and pulp weight with the latitude and the altitude, respectively. Seed yield and weight are negatively and positively correlated to pod width, pod thickness and pulp weight, respectively. In addition, seed weight is positively correlated with the latitude. The geographic pattern of the carob tree and its variability are discussed in this paper.