The present study aimed to evaluate the effect of dietary Moringa oleifera (M. oleifera) leaves and/or seed powder on laying Japanese quail performance in terms of egg production, egg quality, blood serum characteristics, and reproduction. In total, 168 Japanese quails (120 hens and 48 males) at eight weeks of age in laying period were randomly distributed to four treatment groups, with six replicates per group and seven birds (five hens and two males) per replicate. The first group (G1) served as a control group, while G2, G3 and G4 groups were supplemented with M. oleifera leaves (ML) and M. oleifera seeds (MS) and their combination ((1 g/kg ML; 1 g/kg MS; and 1 ML g/kg + 1 MS g/kg (MSL), respectively). From the results, feed consumption, feed conversion ratio, egg weight, fertility and hatchability from fertile eggs, egg and yolk index, and Haugh unit were not affected by dietary treatments. However, egg production, egg mass, eggshell thickness, and hatchability were significantly increased and blood aspartate transaminase (AST) and urea decreased in the MS treatment. Both triglycerides and total cholesterol were reduced (p < 0.05) in all treatments with ML, MS, and MSL, with no significant differences in alanine aminotransferase (ALT), albumin, total protein, globulin, and A/G ratio among dietary treatment. Our results clearly indicated that the inclusion of M. oleifera seeds in Japanese quail diet significantly increased egg production and improved hatchability, along with some egg quality parameters, and also lowered some blood biochemical components.

This study was to investigate the effect of dietary protein levels and supplementation with two cold‐pressed oils on the performance, immunity and antioxidant indices of growing Japanese quails. A 3 × 4 factorial experiment, using 3 dietary crude protein (CP) levels (22%, 24% and 26%) and 4 supplemental herbal oils levels: control without additives, 250 mg marjoram (Mar), 250 mg thyme (Thy) and 125 mg Mar + 125 mg Thy per kg diet. A total of 720 unsexed, 7‐day‐old quail chicks were randomly distributed into twelve treatment groups (4 replicates per group of 15 chicks in each). The live body weight (LBW) on 42 days and body weight gain (BWG) from 7 to 42 days were significantly improved (p < 0.01 and 0.05) in chicks fed 24% or 26% CP compared with those of the 22% CP group. The groups fed diets supplemented with Mar or in combination with Thy oil exhibited significantly better LBW, BWG and feed conversion ratio (FCR) than the control at all periods except BWG from 21 to 42 days and FCR from 7 to 21 days were not significant. Feed intake was gradually decreased with increasing dietary CP level or adding herbal oils during the periods 21–42 and 7–42 days of age. Plasma triglycerides, cholesterol, total lipids and malondialdehyde were decreased by cold‐pressed oils supplementation, but the activity of reduced glutathione and superoxide dismutase was increased (p < 0.01) compared with the control. In conclusion, quails fed a diet containing 24% or 26% CP or diets supplemented with Mar or Thy oils or both exhibited improvement in the performance, lipid profile, immunity and antioxidant capacity without any detrimental impacts on the other studied parameters.

The objective of this review is to control fish bacterial diseases or infections through application of some promising novel biocontrol methods, such as probiotics, bio-encapsulated vaccines, and phage therapy, to avoid the disadvantages of traditional one that potentially affects fish and human health. Bacterial infection in intensive fish farming causes mass mortalities and the treatment of that requires the intensive use of chemicals and antibiotics. Several methods have been tried to control fish diseases including the use of antibiotics, but their haphazard use is associated with potentially negative effects as drug resistance and drug residues. The use of probiotics as biocontrol agents for aquaculture is increasing with the demand for environmental beneficial, eco-friendly alternatives for sustainable aquaculture production. The benefits of such supplements include improved food value, inhibition of pathogenic microorganisms, and increased immune response. The bio-encapsulated vaccine appears to be the most attractive method for releasing of vaccines. Several bioactive molecules which are specific for some diseases have been successfully encapsulated with nanoparticles in order to enhance their availability, bioactivity, and controlled delivery. Recently, "reverse vaccine" by using bio-informatics that aids in designing vaccines against infectious pathogens that are difficult to design, especially the intracellular bacteria. Additionally, the use of bacteriophages for biological control of pathogens in cultured fish has gained much interest. Several bacteriophages have been isolated specific to various pathogenic bacteria. Oral administration of phage cocktail is the most suitable way of application in fish, especially when large number of infected fish should be manipulated. Hence, in the following paragraphs, we will discuss some promising novel biocontrol methods that target the fish pathogens like probiotics, bio-encapsulated vaccines, and phage therapy.

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Streptococcus iniae cause high mortalities in aquaculture farms all over the world. This study aimed to isolate, identify pathogenicity and genetic relatedness of S. iniae obtained from cultured Nile tilapia (O. niloticus) at Kafr El-Shiekh Governorate. Fourteen isolates of pure S. iniae cultures were biochemically identified, and confirmed through amplification and sequencing of the 16S rRNA gene. Experimental challenge with six selected isolates resulted in marked clinical signs similar to those recorded in natural infections. The LD 50 values were ranged between 3.7×10 7 to 4.3×10 8 cfu/fish. All strains were sensitive to oxytetracycline and florfenicol. In repetitive sequence-based PCR (rep-PCR) analysis using the BoxA primer, isolates presented genetic heterogeneity and were divided into six genotypes banding patterns. Understanding the epizootiology and genetic variability between S. iniae isolates, could help for better control and vaccine development.