ross 308

A The use of vitamin C in conditions of heat stress and poultry rejuvenation compared to this stressor has been recorded by researchers for many years (Nameghi 1386). . The experiment was a completely randomized design with 7 treatments and 4 replications, 10 birds each. Treatments included: control diet, 3 level of vitamin C (0, 100 and 200 mg/kg) and 3 level of Nano vitamin C (0, 100 and 200 mg/kg). The experimental diets were based on corn and soybean. During the experiment, water and food were offered ad libitum. Body weight and feed intake at the end of each period were measured and used to calculate body weight gain and feed conversion ratio. At d 42 one bird from each replicate was selected and killed to measure the internal organ weights. Also, the weight and length of the jejunum were calculated, and partly for intestinal morphology in formalin 10%.

The effect of dietary treatments on feed consumption in broiler chickens was significant (P<0.05). Chickens that received 200 mg of vitamin C kg-1 diet had the greatest feed intake than other chicks. The results of this study was in line with the results of Kutlu and Forbes (1993) who reported that 250 mgof vitamin C increased these parameters. Experimental treatments had a significant effect on the weight gain of chicks (P<0.001). Chickens that received 50 mg nano vitamin C had the greatest weight gain compared to other treatments. According to these results, Roshani et al. (2006) reported that vitamin C during the stress period improved the feed intake and daily weight gain. Sahin and Kucuk (2002) reported that the use of 200 mg vitamin C /kg of diet improved the feed intake of quails under stress conditions. Gross (1988) showed that vitamin C under stress conditions caused an increase in daily weight gain in broiler chicks. In another study, Ping et al. (2011) showed that nano multivitamin improved weight gain, feed intake and reduced mortality. Chicks fed 50 mg nano vitamin C had the best conversion ratio compared to other treatments. The results of this experiment are consistent with the results of Alba et al. (1393), Kutlu and Forbes (1993), and Amakye et al. (2000). They reported that the use of vitamin C supplementation significantly reduced the feed conversion ratio compared to the control group. Sahin and Kucuk (2002) reported that using 200 mg/kg of vitamin C improved feed consumption and feed conversion ratio under heat stress. Researchers reported that vitamin C supplementation in summer did not have a significant effect on the relative weight of the thigh, which is similar to the results of this experiment (Konca, 2009). Relative weight of breast and carcass was affected by experimental treatments and a significant difference was observed between the groups. The greatest relative weight of the carcass was related to birds received 200 mg vitamin C kg-1 diet. The greatest relative weight was related to treatment with 50 mg nano vitamin C. According to these results, Sahin et al. (2002) reported that vitamin C supplementation of 250 mg/kg of diet improved live weight, nutritional efficiency and carcass traits. Also, Roshani et al. (2006) reported that vitamin C supplementation during the stressful period significantly increased the weight of the chest. Rafie et al. (1393) reported that 250 mg/kg vitamin C increased breast weight and could somewhat reduce the negative effects of heat stress. Darmankouhi (2005) reported that ascorbic acid increased the carcass quality and yield under heat stress conditions. Relative weight of liver was not affected by experimental treatments. The effect of treatments on relative weight of spleen was significant (P<0.05). Chickens fed 100 mg of vitamin C had the greatest relative spleen weight. An experiment showed that vitamin C had no significant effect on different gastrointestinal system (Konca, 2009). Nemati et al. (1392) reported that the use of antioxidants such as vitamin C under stress conditions, reduced spleen relative weight, immune system, and mortality. Raeisi et al. (1394) showed that the effect of different levels of vitamin C on the relative weight of the spleen and liver was significant. The greatest amount of relative length of jejunum was belonged to birds received 100 mg of nano vitamin C. This level was significantly different from that of the control group and 50 mg vitamin C (P<0.05). The relative weight of the jejunum was not affected by the treatments. Treatments did not have a significant effect on white blood cells. The greatest amount of RBC was related to treatment with 200 mg nano vitamin C (P<0.05). This treatment was significantly different from control treatments, 50 mg vitamin C, 50 mg nano-vitamin C and 100 mg vitamin C (P<0.001). The greatest amount of hemoglobin was related to the level of 200 mg nano vitamin C (P<0.001). The experimental treatments did not have any effect on the heterophile levels. The greatest amount of lymphocyte was related to birds fed 50 mg and 100 mg nano vitamin C(P<0.001), which had a significant difference with 200 mg vitamin C and nano vitamin C (P<0.05). Gross (1988) showed that the number of lymphocytes was increased by the use of vitamin C in broiler diets. Taghilu et al. (1389) showed that 0.05% of vitamin C improved hematocrit. Regarding the effect of vitamin C, Tuleun et al. (2011) showed that vitamin C had no significant effect on blood cell parameters. In another study Mirzapoor et al. (1394) examined levels of 250 and 500 mg of vitamin C on blood parameters. Results showed that vitamin C increased the amount of red blood cells and hemoglobin and improved hematocrit of the blood.The greatest amount of glutathione peroxidase enzyme was related to the level of 200 mg nano vitamin C kg-1 diet(P<0.001), which was significantly different from other treatments. Research has shown that vitamin C has an electron capability that acts as a regenerator of active oxygen species (ROS) and has a moderating role in the antioxidant defense activity (Sies et al. 1995). Chickens that received different levels of vitamin C and nano vitamin C had a significant difference compared to the control group (Data was not shown in this article).. Rafiei et al. (1393) showed that lemon powder with 250 mg/kg of vitamin C reduces the negative effects of heat stress and improves the immune response of the bird. Pardu et al. (1985) reported that the consumption of 1000 mg/kg of vitamin C would increase antibody production against SRBC. Mccorre et al. (1980) showed that ascorbic acid can increase the activity of B lymphocytes improving humoral immune responses. Amakye et al., reported vitamin C improve humoral immune response in broiler chicks.

The results of this experiment showed that consumption of 50 mg nano vitamin C kg-1 diet had a positive effect on growth performance of broiler chicks, thus improving the weight gain and feed conversion ratio. Also increased the weight of the liver, spleen and bursa, and improved immune function and the rate of humoral immune response. Also, 200 milligrams of nano-vitamin C kg-1 diet increased the concentration of hemoglobin and glutathione peroxidase enzyme under heat stress conditions.

This study was performed to compare the effect of diets containing ethanolic extract of Echinophora platyloba at two levels of 0.3% and 0.5% and Phosphoflavomycin growth-promoting antibiotic (0.04%) on performance, immune response, and blood biochemical characteristics of broilers using 160 male day-old chicks in a completely randomized design manner using 4 experimental groups, 4 replications and 10 chicks in each experimental unit. The results indicate that in the fourth week of production, there was a significant increase in body weight of the treatment receiving Echinophora platyloba extract (0.3%) compared to other experimental groups (P≤0.05). On day 14th, in both groups fed with Echinophora platyloba extract (0.3 and 0.5%), a significant increase in feed conversion ratio was found when compared to the control and growth promoter antibiotic treatments (p≤0.05). The treatment fed with 0.3% Echinophora platyloba extract increased the percentage of carcass and spleen significantly (p≤0.05) when compared with other dietary treatments. No significant changes are found due to both levels of Echinophora platyloba extract on immune response and blood biochemical parameters of broilers. In contrast, the group fed with antibiotic significantly reduced the blood levels of LDL and ALP, when compared with control and 0.3% Echinophora platyloba groups (p≤0.05). In general, the application of Echinophora platyloba extract (0.3%) led to a significant improvement in performance and some carcass traits percentage of broilers and could be recommended as a suitable alternative to antibiotic growth promoters.

The knowledge of the requirement of essential amino acids helps to optimize the different nutritional inputs at various stages of broiler production. Before production of synthetic amino acids, protein was included in diets at rates far above animal requirements as a safety margin against amino acid deficiencies. Today, most necessary amino acids can be obtained in the crystalline form. Addition of these amino acids firstly allows for reduced dietary crude protein inclusion rates and secondly supplies the animal with an amino acid balance that is closer to that requirement of the animal. Recent studies showed Valine (Val) to be the 4th limiting amino acid in vegetable based of broiler diets (Han et al 1992). It seems that the amount of the 4th limiting amino acid depends on the diet composition and animal species (Fernandez et al 1994). The NRC (1994) recommendation for total Val in the grower periods is 0.82 % of diet. Corzo et al. (2008) estimated dig Val requirement during 14 to 28 d (0.9% of diet) which were higher than NRC (1994) total Val recommendation of 0.82%. Little information is available on the response of Val usage on improving the tissue protein synthesis in broiler chickens. However, the appropriate programs of eugenics in recent decades will continue to increase poultry productions and therefore, it is necessary to constantly improve and update responses of animals to amino acids usage. The aim of this experiment will be determining the valine requirements and the effect of digestible Val on performance characteristics in commercial varieties of broiler chick (Ross 308). To determine Val requirement for growth performance of male broiler chicks, a total of 450 chicks, was assigned to 6 treatments with 5 replicates (with 15 birds per each replicate) from 8 to 21 days of age using a completely randomized design. Corn-soybean meal based diet was formulated to provide all nutrients except for Val. Basal diet was formulated with 0.74% Val and 1.056% lysine (Lys) content. In other diets, Val content was increased by adding L-Val with simultaneous decreasing in L-Glutamic acid from the basal level to provide isonitrogenous feeds. Dietary Val was supplied in 6 levels from 0.74 to 0.99% during the experimental period. Body weight gain and feed intake were measured during the period (d 8 -21). Val intake, feed conversion ratio (FCR), and feed efficiency ratio (FER) were calculated from feed intake data and there was no dead bird in experimental period. All data were analyzed based on a completely randomized design by GLM procedure of SAS (9.1). Duncan’s multiple range tests was used to study the differences between treatment means. Estimations of Val requirements were done at 95% of the plateaus of nonlinear regressions. Broken line Regression analysis was used to estimate Val requirements, when nonlinear regressions responses were statistically significant (P<0.01). Result of this study showed that digestible Val requirement for Ross 308 male broiler chicks is the well fitted based on weight gain, feed intake, and feed conversion ratio. Evaluated digestible Val content for these performance parameters were 0.85, 0.95 and 0.84 % of diet, respectively. The result of this experiment showed that all performance parameters were significantly affected by Val supplementation in the diet (P< 0.01). The broiler chickens fed with 0.89 % of digestible Val level had the highest feed efficiency ratio, but the lowest feed conversion ratio (P<0.01). In this experiment, the digestible Lys content of the basal diets was 1.056% and the best digestible level for weight gain and feed conversion ratio were 0.85 and 0.84%, respectively. According to this information, the level of Val as a digestible ratio to Lys for weight gain and feed conversion ratio was 80.49 and 79.54 for linear broken linear model, respectively. Several studies have addressed the valine needs for broilers in starter phase (Thornton et al 2006). Baker et al. (2002) and Corzo et al. (2008) conducted two studies about of evaluation of the Val requirements for broiler chicks, but, there are many remarkable differences between their study and the present experiment. Although several researches with many similarities have been performed on Val requirement, their results are remarkably different. It could be originated from diet types (purified or practical diet), Leucine levels of diets, crude protein content of basal diet, immunological stress, amino acids interactions, metabolizable energy content of basal diet, broiler strains, age, extended experimental period, sex of broiler and amount of feed intake (D'Mello 1974). The results of the current study suggested that the level of 0.93% digestible Val is the best level for an optimum performance of body weight gain and the level of 0.91% digestible Val is the best level for an optimum feed conversion ratio in growing broilers from 8 to 21 days of age. Based on statistical model and evaluated performance parameters for requirements, clearly differences were observed between result of this experiment for Val requirement in grower period of Ross 308 broiler chicks and other data sources.

Sex of birds creates a fundamental difference in the physiological and nutritional requirements. For example, the feed conversion ratio of female broiler chicks is higher than that of males (over 30 days of age), which results in more fat storage in the body of females (Verapeen and Driver 2000). Although there are several reports on the superiority of male chicks to females in various economic traits such as average daily gain (Verapin and Driver 2000; Ojedapo et al. 2008; Zamani et al. 2012); feed intake (Fischer 1985; Laseinde and Oluyemi 1994; Zamani et al. 2012) and carcass traits (Verapeen and Driver 2000; Ojedapo et al. 2008; Zuowei et al. 2011; Taghan Agh et al. 2011), on the contrary, it has been shown that the mixed rearing of males and females leads to stimulation of protein anabolism, nitrogen uptake and mineral retention and so a higher weight gain at the end of the breeding period (Iyeghe –Erakpotobor 2001). This study was conducted to compare the bio-economic indexes of broiler production with different sex ratios from 11 to 42 days of age.
Material and The experiment was done using 180 Ross 308 broilers in 5 sex ratio groups (Group 1: 25% male and 75% female, Group 2: 50% female and 50% male, Group 3: 75% male and 25% female, Group 4: 100% female and Group 5: 100% male) with 3 replicates and 12 birds per replicate by employing a completely randomized design. Grower (11-24 days) and finisher (25-42 days) periods’ ration of broilers were balanced based on Ross-308 catalog. Feed intake (FI), average daily gain (ADG) and feed conversion ratio (FCR) were measured for each experimental group at the grower (11-24 days), finisher (25-42 days) and total (11-42 days) periods based on the hen- day method. At the end of the experiment (forty-second day), European Production Efficiency Factor (EPEF) and European Broiler Index (EBI) and also carcass traits after 9 hours starving were calculated by selecting 4 chicks per pen considering the sex ratio of each group. For economic evaluation, an index was formulated to determine the worst and best rearing periods (2014-2015) and then costs of grower and finisher rations based on 3 ways of pricing (Rials/kg) contains mean price of 2015, mean price of worst period and mean price of best period were estimated. To estimate income and profit, 3 methods of sale methods were included sale of live chicken, sale of carcass and Half-split sale. So, means of income and profit (Rials/chick) in studied groups were estimated based on 9 economic evaluation methods (3 sale methods×3 pricing methods).
Feed intake was significant only in grower period (11-24 d) and groups with 25% and 75% males had the highest amount of feed intake (P According to the results of comparing profit using different economic evaluation methods, it can be recommended that mixed sex production of broiler chickens will be alright when the proportion of males not to be less than 50%.

The objective of this study was to investigate the effect of different levels of benzoic acid on performance and carcass characteristics of broiler chickens. To this purpose 120 one-day-old Ross 308 chickens were examined with a completely randomized design with 4 treatments, 3 replications and 10 sub sampling that were reared for 42 days. Dietary treatments included of the 0, 0.25, 0.5 and 1 percent levels of benzoic acid. Properties were measured included weight gain, feed intake and feed conversion rate. Dietary supplementation of benzoic acid significantly decreased feed intake of chickens (P<0.05) and the highest feed intake observed in control group. There was no significant difference between BA0.25 and BA0.5 groups in terms of body weight gain (P>0.05). Supplementing 1% benzoic acid in the diet resulted in significant decrease in body weight gain (P<0.05). Use of 0.25 and 0.5percent benzoic acid in the broilers diet in contest of control group significantly decrease FCR (P<0.05). Also inclusion of benzoic acid in the diet resulted in significant decrease breast to carcass weight ratio in 0.5percent treatment (P<0.05) but thigh to carcass weight ratio significantly increased in the treatment of 0.5 percent of benzoic acid than control group. Regarding to present results, suggested that use of 0.5 percent dietary supplementation of benzoic acid in broiler chickens is possible without negative effects on performance and carcass characteristics.