Miswak (Salvadora persica) dietary supplementation improves antioxidant status and nonspecific immunity in Nile tilapia (Oreochromis niloticus).

Nile tilapia (Oreochromis niloticus) is the most common aquaculture fish, but is exposed to various pollutants and may be susceptible to infectious diseases due to reduction in their antioxidant status and immune defense. Therefore, researchers have tried to find feed supplements of natural origin to increase the health status of fish and decrease the incidence of drug resistance. The current study was conducted to investigate the effect of dietary supplementation of Miswak (Salvadora persica, SP) on Nile tilapia. Fish were randomly allocated into four experimental groups (30 fish each); the control fish were fed on the basal commercial diet and the SP-treated groups were fed basal diet supplemented with different concentrations 0.5, 1, and 2% for 30 days. The SP supplementations had no significant effects of SP on fish growth performance traits and lipid profiles but augmented the serum protein and globulin levels. The SP significantly improved the hepatic antioxidant status through the significant decrease of malondialdehyde (MDA) and the increases of reduced glutathione (GSH) levels and the activities of total superoxide dismutase (T.SOD), catalase (CAT) and glutathione peroxidase (GPx), especially in the SP 1% group, while glutathione S-transferase (GST) activities were significantly increased due to SP in a dose-dependent manner. The same results were obtained for the mRNA expression of CAT and GPx. Regarding the nonspecific immune status of the fish kidneys, SP, especially SP1, significantly increased interleukin-1 beta (IL-1ß) and interferon-gamma (INF-γ). The data of the present study revealed the protective effect of SP on Nile tilapia health status. Therefore, SP can be considered as a promising feed additive for Nile tilapia.

Effects of supplementing broiler diets with coriander seed powder on growth performance, blood haematology, ileum microflora and economic efficiency.

A total of 480 one-day-old Arbor Acres broiler chicks were randomly assigned to four dietary groups, each including six replicates (n = 20/replicate). Broilers in the first group (G1) were fed a basal diet without any additives (control). Broilers in groups 2, 3 and 4 (G2, G3 and G4) were fed a basal diet supplemented with 0.1%, 0.2% and 0.4% coriander (Coriandrum sativum L.) seed powder (CSP) respectively. Feeding trials lasted for 42 days, and after that growth, carcass traits, haematological parameters, gut microbiota and economic efficiency (EE) were evaluated. Final body weight (FBW), total weight gain (TWG), total feed intake (TFI) and red blood cell (RBC) counts of broilers in the G4 and G3 treatment groups were significantly higher (p < .05) compared with broilers in the G1 treatment group. The feed conversion ratio (FCR) was better (p < .05) in the G4 treatment group (1.72) than in the G1 treatment group (1.84). Broilers in CSP treatment groups had significantly higher haemoglobin (Hb) concentrations, packed cell volume (PCV) and platelet counts, and had lower (p < .05) Escherichia coli and Clostridium perfringens counts compared with broilers in the G1 treatment group. Dressing, liver, pancreas, bursa and thymus percentages were higher (p < .05) in broilers in the G4 (70.30, 3.18, 0.31, 0.10 and 0.32% respectively) treatment group, compared with broilers in the control (G1) group (66.57, 2.37, 0.23, 0.04 and 0.21% respectively). Broilers in treatment groups G4 and G3 had lower percentages of abdominal fat and lower total bacterial counts (p < .05) than broilers in treatment groups G2 and G1. The highest economic efficiency (EE) was found in treatment group G4, and EE in this group was 13.06% greater than in the control (G1) group.

Effect of essential oils on the immune response to some viral vaccines in broiler chickens, with special reference to Newcastle disease virus.

This trial assessed the efficacy of a commercial essential oil (EO) product on the immune response to vaccination against Newcastle disease (ND) and subsequent challenge with virulent ND virus genotype VII (vNDv genotype VII) by using the following experimental groups of broiler chickens (Each group had 21 birds with 3 replicates in each, n = 7): NC (negative control), PC (positive control), VC (vaccinated), and VTC (vaccinated and treated with EOs). Moreover, in a trial to study the effect of EOs on vNDv genotype VII in vivo as a preventive or therapeutic measure, 2 additional ND-vaccinated groups were used (PRV: medicated 1 D before vNDv challenge for 5 D; and TTT: medicated 2 D after vNDv challenge for 5 D). In addition, the immune-modulatory effect of EOs on the avian influenza (AI), infectious bronchitis (IB), and infectious bursal disease (IBD) vaccines was assessed through the serological response. The use of EOs along with administration of ND vaccines (VTC) revealed a lower mortality rate (42.86%), clinical signs, and postmortem lesion score (11) than ND vaccines alone (VC) (52.28% mortality and score 15), in addition to lower hemagglutination inhibition (P < 0.05) (6.5 ± 0.46) and viral shedding (10 log 2.28 ± 0.24) titres 1 wk after challenge in comparison with VC (8.63 ± 0.65 and 10 log 3.29 ± 0.72, respectively). Nevertheless, the EOs mixture (VTC) (1952 ± 28.82) did not significantly (P > 0.05) improve growth performance compared with the nontreated birds (NC and VC) (1970 ± 19.56 and 1904 ± 38.66). EOs showed an antiviral effect on vNDv in vivo (in chickens) as a preventive measure (PRV) as well as some therapeutic effect (TTT) through decreasing the viral shedding titres (loNC0), mortality rate, and severity of clinical signs and postmortem lesions, in addition to serum malondialdhyde level. Regarding the other viruses, the EOs mixture did not improve the immune response to the AI and IB vaccines but significantly (P < 0.05) increased the ELISA antibody titre for IBD virus at the 28th D of age (2,108 ± 341.05). The studied EOs mixture showed an immune-stimulating response to ND and IBD vaccines, antiviral effect against ND virus, especially if administered before the challenge; however, it did not have a growth-promoting effect.

Laying Performance, Physical, and Internal Egg Quality Criteria of Hens Fed Distillers Dried Grains with Solubles and Exogenous Enzyme Mixture.

: The effects of dietary inclusion of distillers dried grains with solubles in laying hen diets with and without exogenous enzyme mixture (EEM) on performance and egg characteristics were evaluated. One of the main objectives of this study was to examine the effects of distillers dried grains with solubles (DDGS) and enzyme cocktail on egg yolk fatty acids. The study used total of 144 Hisex Brown laying hens in a 4 × 2 factorial arrangement, including four levels of DDGS (0, 6, 12, and 18% of diet) and two levels of enzyme cocktail (0 or 250 mg EEM/kg of diet) through 32⁻42 weeks of the age. The inclusion of 18% DDGS was associated with the worst (p ≤ 0.001) egg production and the lowest daily feed intake. Numerically, hens fed 6% DDGS diet consumed more feed and had the greatest egg production. The best feed conversion ratio (FCR) was recorded in the control, while the worst was recorded in the 18% DDGS group. Compared with EEM-free diets, EEM supplementation improved FCR by about 2.79%, but the difference was not significant. Shell thickness and shell percentage were significantly increased in hens fed 6% DDGS diet compared to other groups. Egg weights in the 6% and 12% DDGS groups were significantly higher than those in the control and 18% DDGS groups. Non-significant increases in shell and albumin percentages were recorded in groups fed EEM-supplemented diets. The interaction effect of DDGS and EEM was significant (p ≤ 0.01) for the majority of egg characteristics. As dietary DDGS level increased, yolk color density increased. Elevating DDGS level up to 18% increased yolk cholesterol, total fat, and total unsaturated fatty acids. The effects of EEM supplementation on egg yolk fatty acid composition and the interaction effects between DDGS and EEM were not significant. Considering these results, it could be concluded that DDGS is an acceptable feed ingredient in layer diets and that the maximum inclusion level of DDGS should not exceed 12% of the whole diet.

Single and Combined Effects of Clostridium butyricum and Saccharomyces cerevisiae on Growth Indices, Intestinal Health, and Immunity of Broilers.

A total of 120 1-day-old commercial Cobb chicks were used to study the effects of Clostridium butyricum (C. butyricum) and/or Saccharomyces cerevisiae (S. cerevisiae) on growth performance, intestinal health, and immune status in broilers. The experimental groups were as follows: G1; basal diet (BD), G2; basal diet (BD) plus C. butyricum preparation at 0.5 g/kg diet, G3; BD plus S. cerevisiae preparation at 0.5 g/kg diet, G4; BD plus 0.25 g/kg C. butyricum preparation plus 0.25 g/kg S. cerevisiae. Results showed that the total body weight gain, feed conversion efficiency, and protein efficiency ratio were significantly higher (p < 0.05) in the G4 group than in the other groups. The mortality percentage was reduced in the probiotic-supplemented groups. The villi height was elongated, and the villus height/crypt depth ratio was significantly increased in G2 and G4 chicks, compared to those in the control. The crypt depth was significantly decreased in all the probiotic-supplemented groups. Hemagglutination inhibition titers for Newcastle disease virus (NDV) were markedly increased in G2 and G4 chicks at 35 days of age, compared to those in G3 and control chicks. These results showed that dietary supplementation of a combined mixture of C. butyricum and S. cerevisiae in an equal ratio (G4) was more effective in improving growth performance, immune status, and gut health of broilers, compared with individual supplementation at a full dose.