No abstract

eventy two New Zealand White rabbits (NZW) at 25 days of age were used to study the effect of of different dietary starch and protein levels on productive performance, nutrients digestibility coefficients, carcass characteristics, digestive tract measurements, blood constituents, enzymes activity and economical evaluation. The rabbits were fed on six experimental diets containing 3 levels of starch {16 (LS), 19 (MS) and 22% (HS)} and 2 levels of protein {14 (LP) and 16% (OP)} in a factorial arrangement design. The results obtained are summarized as follows:-Best results for live body weight (LBW) were obtained for rabbits fed 16% starch and 14% protein diet at the end of growth period (81 days of age). Decreasing of dietary starch and protein levels had a positive effect on average daily body weight gain (DBWG) in overall growth period (25-81 d.). Daily feed consumption (DFC) was affected by different levels of starch, but no protein level. Feed conversion ratio (FCR) was improved at moderate dietary starch and low dietary protein levels. Mortality rate of growing rabbits improved due to decreasing dietary protein levels. However, dietary starch levels had no effect.-Rabbits fed low levels of starch and protein in their rations significantly increased DM, OM, CP, NFE, starch and sugar digestibility coefficients and nutritive values (TDN and DCP). Neither dietary starch nor protein levels had impact on CF, neutral detergent fiber (NDF), acid detergent fiber (ADF) and EE digestibility.-There were not significant effects of starch and protein levels on dressing percentage, hot carcass weights (%), blood total protein, albumin, globulin, albumin/globulin ratio, liver activity enzymes (GOT and GPT). While, high starch level in the diet increased significantly liver weight (%) regardless of protein content.-Blood glucose, triglycerides and total protein content, amylase and protease enzymes activity in the stomach, ileum and cecum were significantly increased, while degree of pH for stomach, ileum and cecum contents was decreased by decreasing starch and protein levels in the diet. In addition, non-significant was observed in the cellulase and carboxymethylcellulase as affected by the different levels of protein and starch in all segents of the digestive tract. The results show that, total VFAs in the cecum and blood were high with 16% starch and 14% protein.-Economic efficiency and performance index were improved for rabbits fed (MS-LP) diet. However, production efficiency factor was improved for rabbits fed (LS-LP) diet. In growing rabbits, it was concluded that high correlation exists between dietary starch and protein levels which was reflected on productive performance, digestibility coefficients, digestive tract measurements and economic efficiency.

hree experiments were conducted to investigate the effects of drinking water supplementation with 0, 5 and 10 ppm of Nano-silver particles (AgNPs) / liter on performance, carcass characteristics and gut micro-flora population of grower rabbits from 63 to 91day of age, broiler chicks from 1 to 42 day of age and grower Japanese quails from 7 to 42 days of age. Results showed that, different levels of AgNPs in drinking water hadn't any significant effect on body weight, body weight gain (BWG) or feed conversion ratio (FCR) of rabbits. Concerning broiler chicks; the control group performed well compared with supplemented groups. Both BWG and FCR for Japanese quails recorded best values for 10 ppm supplemented group compared with control group. In all tested poultry species, the levels of 5 ppm and 10 ppm resulted in a reduction in total viable bacteria, pathogenic bacteria representing E Coli and beneficial bacteria representing Lactobacillus of intestinal gut especially for 10 ppm level causing negative effect on performance of grower broiler chicks but less on grower rabbits or Japanese quail, suggesting that, both species may be less sensitive for existence of AgNPs in drinking water, while broiler chicks might be more sensitive. Most of carcass characteristics were not significantly affected by existence or level of drinking water AgNPs supplementation except liver percent of grower quail, which needs to undergo more research works.

n experiment was conducted to study the effect of feeding recommended (23%, Diet 1) or high (25%, super starter, Diet 2) crude protein in starter diets on productive performance, carcass characteristics and economical efficiency of Hubbard broiler chickens. A total of 225, day old Hubbard broiler male chicks were randomly distributed into 5 treatments at (1-35) days of age, each with three replicates of 15 birds each. The five treatments were: T 1) Control group, chicks fed (Diet 1) ad-libitum the other treatments from T 2 till T 5 , chicks were fed (Diet 2)at different quantities being 125g, 250g, 375g and 500g/chick, respectively followed by (Diet 1) to the end of starter period (14 days of age). During grower and finisher periods, all chicks were fed recommended diets at these phases. At the end of experiment at 35 days of age, 4 broilers chicken per treatment were slaughtered and evaluated for carcass traits. The results indicate that: Body weight, body weight gain and feed intake were linearly increased, whereas feed conversion ratio decreased as super starter diet increased, during overall period (1-35 days of age). The best values of body weight gain, feed conversion ratio, protein and energy conversion ratio were observed for chickens fed 500g super starter diet compared with other dietary treatments. In most cases differences between treatments were significant (P≤0.01). Carcass characteristics of chicks fed super starter diet, added at different levels had no effects on carcass characteristics. The best economical efficiency value were demonstrated when broiler chickens fed (500g Diet 2 /chick) super starter diet and the values was 33.09% more when compared to that of chicks fed control diets. In conclusion, feeding broiler chickens super starter diet at level of (500g/chick) support and enhance productive performance and economical efficiency.

The objective of the work was to investigate the response of broiler chicks to supplementing guanidine acetic acid (GAA) in diets with different protein levels on performance and carcass characteristics. A total number of 360 one day old of male Hubbard broiler chicks were weighted and divided into sex dietary treatments of 60 chicks each with 6 replicates (10 chicks each), in 2 x 3 factorial design as follows:T 1 standard diets without feed additives (SD), T 2 SD (T 1 diets) + 0.06% (GAA) T 3 SD (T 1 diets) + 0.12% (GAA), T 4 Tested diets (-2% CP) without feed additives (TD), T 5 TD (T 4 diets) + 0.06% (GAA), T 6 TD (T 4 diets) + 0.12% (GAA).The results indicated that:-Productive performance of broiler chicks including live body weight: Body weight gain, feed conversion ration, performance index, production efficiency factor, protein conversion ratio and energy conversion ratio were significantly affected by feed additives (GAA) and levels of crude protein at experimental period (1-35 days) of age. Feed intake recorded insignificant response due to experimental factors (feed additive or protein level). -Carcass characteristics: Dietary treatments with different (GAA) levels (0, 0.06 and 0.12%) or different protein levels had no significant effect on most studied parameters. It may be concluded that broiler diets containing -2% crude protein + 1200 g GAA/ ton or standard diets + 600 g GAA/ton would be reason for achievement of maximum performance without adverse effect on carcass parameters.