INFLUENCE OF DIETARY VITAMIN C SUPPLEMENTATION ON GROWTH PERFORMANCE, BLOOD BIOCHEMICAL PARAMETERS AND TRANSCRIPT LEVELS OF HEAT SHOCK PROTEINS IN HIGH STOCKING DENSITY REARED BROILER CHICKENS

This study was conducted to evaluate the effects of dietary supplementation of different levels of vitamin C (VC) in broiler chicken reared under high stocking density on the growth performance, blood biochemical parameters and the expression of heat shock protein genes. A total of 150, one day old mixed sex broiler chicks (Cobb 500) were randomly distributed in five equal groups. Group1 was reared in normal stocking density (10.6 birds/m2) and fed on the basal diet (BD) without VC (control). While, chicks in other groups (2, 3, 4 and 5) reared in high stocking density (15.6 birds/m2) and fed on BD supplemented with VC at 0, 200, 400 and 600 mg / kg diet, respectively. Birds reared in high stocking density showed a reduction of the final body weight and total feed intake, with high mortality (6.6%). Moreover, they revealed a significant up-regulation of HSP70 mRNA and elevated HSP90 and HSF1 mRNA expression in heart and liver tissue. Graded dietary levels of VC provided variable protection against the hazard of high density through improved final body weight and total feed intake, decreased the mortality % and downregulated liver HSP70 expression level. However, the best performance was observed in birds supplemented with 200 mg/kg VC (group 3). Key words: chicks' growth performance; gene expression; stocking density; vitamin

Reproductive Performance of Barki Rams Fed on Different Omega-6: Omega-3 Ratios

The current experiment intended to investigate the impact of various dietary omega- 6/ omega -3 fatty acids ratios (FAs) on the reproductive performance and  serum lipid profile  in male Barki sheep over two months' experimental period. Twelve males were randomly allotted into 4 equal groups receiving 4 different ratios of omega-6/ omega- 3 FAs including 5.40 (higher ratio, HR), 4.56 (medium ratio, MR), 3.13 (lower ratio, LR) and 1.76 (very low ratio, VLR):1.  Feeding rams on diets with HR or VLR did not exhibit substantial impact on the sperm motility, sperm viability and testosterone hormone, however these parameters were non-significantly improved in the MR and LR- fed rams. The semen volume was significantly increased (P < 0.05) with the MR in comparison with the remaining groups.  Serum biochemical parameters, including total lipids, HDL concentrations did not exhibit significant differences (P> 0.05) among the different ratios. VLR- fed rams showed the higher serum total cholesterol, triglyceride, LDL and VLDL (P< 0.05), while the MR fed rams showed the highest CHO/HDL ratio (P< 0.05) in comparison with the other ratios. In summary, Barki rams fed different omega-6/ omega- 3 PUFA ratios (5.4, 4.56, 3.13 and 1.76:1) containing diets exhibited no significant difference in their reproductive performance parameters, however the medium (4.56:1) and low (3.13:1) ratios showed potential improving 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