جستجوی مقالات مرتبط با کلیدواژه « amino acids » در نشریات گروه « علوم دام »

The objective of this study was to determine ileal digestibility of amino acids (AA) of canola meal using the standardized ileal digestibility (SID, ad libitum-fed), and a precision-fed ileal broiler assay (force-fed). For the SID, sixteen male Ross 308 broilers were fed a semipurified diet with 20% crude protein and containing canola meal as the only source of protein from 17 to 21 d, with ileal digesta collected at 21 d. For the precision-fed, sixteen )four groups of four chicks( 21-d-old male Ross 308 broilers were precision-fed by 10 g of semipurified diet containing canola meal mixed with chromic oxide, and ileal digesta were collected at 4 h post feeding. Then, ileal digesta samples were lyophilized, AA and chromic oxide concentration determined and standardized ileal digestibility of AA was calculated. Results showed that digestibility values for Lys, Val and His for SID assay were greater than precision-fed assay, and these values were greater for Thr, Phe and Asp for precision-fed assay than SID assay (P

Poultry industry is growing rapidly throughout the developing countries. There have been a considerable increase in growth rate and feed efficiency in commercial broiler chickens in recent years. The improvement of poultry production highly depends on the synergy between science and practice. By use of modern technology, genetics, microbiology, informatics and nutrition knowledge, production of fattening chicken highly increased in the whole world in last years. Also shorter production period and lower quantity of feed which is needed per kg of weight gain is the main goal of broiler production (Steiner et al. 2008). Poultry feeding is biologically and economically very important factor in broiler production. Feed cost is approximately 65-70% of the total production cost (Esonu et al. 2003). Energy and protein are very important nutrients for formulation of broiler diets. They are determinants in the evaluation of the performance and production coefficients of poultry. Protein and energy having major effect on growth performance of the broiler and they are the most expensive nutrient in broiler diets. Costs are rising along with the development of the poultry industry. Furthermore, there is a limitation on the feed sources which produced in Iran and to prevent loss of nutrients, evaluating the economy of poultry industry is important. Also there are several limiting factors such as environmental conditions which lead to lower weight gain and higher feed conversion ratio as compared to the standard performance in current broiler house in Iran. For these reasons, by feeding chickens with the diluted diets may achieve to the reasonable broiler performance while reducing the production costs. Therefore this experiment was conducted to evaluate the productive and economic performance of broiler chickens fed with different level of energy and digestible amino acids.
Material and This study was conducted at the veterinary organization of Khorasan Razavi. A total of 1440 day-old Ross 308 broiler chickens were reared with standard diet during the first ten days of age and then randomly divided into twelve treatment groups. The chickens were arranged as 3×4 factorial completely randomized experimental design according to 3 levels of energy (100, 95 and 90% of Ross 308 recommendation) and 4 levels of protein and essential digestible amino acids (100, 105, 95 and 90% of Ross 308 recommendations). Each treatment considered of 3 replicates of 40 chickens per experimental unit. The birds were reared on the litter pen for 42 days with ad libitum access to feed and water. Experimental diets were formulated to provide similar nutrients content (expect protein, amino acids and energy levels) according to the Ross 308 recommendations. The standard composition and analysis of the diets are given in Table 1. Diets were formulated base on linear programming by using of the UFFDA software. Feed intake (FI) and body weight gain (BWG) were recorded for each period on pen basis, and the data was used to calculate feed conversion ratio (FCR). Mortality was recorded on daily basis, and dead weight recorded to correct FCR. The economic evaluation was performed according to cost of feed intake per kg weight gain; that was calculated as multiplying FCR in cost of each kg diet (Obih and Ekenyem 2010). Data were analyzed using the General Linear Models (GLM) procedure of SAS (SAS, 2003). The differences between the means of groups were separated by Tukey Multiple Range test (P In case of energy levels, the main effects showed that, there was no significant difference between FI and BWG, whereas, feed cost per kg final BW was lower in the diet containing 90% energy. These results are in agreement with NRC (1994), which reported that it is not always true to conclude the poultry can adjust feed intake to achieve a minimum energy from diets containing different levels of energy. Similarly, Leeson et al (1996), Nguyen and Bunchasak (2005) and Jafarnejad and Sadegh (2011) found no significant effect on BWG of broiler chicks fed the diets containing different levels of energy. In the study using Hubbard × Hubbard broilers, Aftab (2009) reported that, the diets with the higher energy (2850 kcal) resulted to the lower feed intake and FCR in day 35.
Broilers fed with the diet containing 90% of amino acids had the lowest BWG and feed cost than those fed with other levels of amino acids. Aftab (2009) reported that with increasing balanced protein from 8.4 to 10.2 g per kg, the FI and BW linearly improved (p The present results demonstrated that balancing diets with 90% of amino acids and 95% of recommendation energy not only decreased feed cost but also partly improved performance of broiler chickens.

An experiment was carried out to investigate the effects of in ovo injection of certain nutrients on small intestinal morphology، immune organs weight and growth Performance in broilers. Three hundred and sixty fertile eggs (from Ross 308 broiler breeders) were randomly assigned to six groups including: non-injected (control 1) and injected into the amnion with 0. 7 ml distilled water (control 2)، blend of amino acids، albumin 20%، dextrose 20% and dextrose 10%) with four replicates of 15 eggs in each replicate. Injections were undertaken into the broad end of eggs by 23- gauge needle with depth of 25 mm. The highest villus height and villus height to crypt depth ratio at 1 d old chicks were observed in amino acid and albumin injected groups in compared to control 1، control 2 and dextrose 20% treatments. The results indicated that in ovo injection of albumin increased body weight in the first day of hatch in comparison to control treatments. At 7 d of age، villus height of chicks hatched from albumin injected eggs was significantly greater than control1 treatment. Injection of different nutrients significantly increased the relative weight of thymus in compare to control 1. Nevertheless، there were not any significant effects on feed intake، feed conversion ratio، hatchability percentage، percentages of different white blood cells، relative weights of bursa، small intestine، and relative length of small intestine. In conclusion، it seems that in ovo injection of nutrients، especially albumin and amino acids can be helpful to improve chick’s birth weight، small intestine morphology and immunity of broilers.

To determine the amount of food amino acid and to spend time in the laboratories are expensive & time-consuming due to a chemical analysis. In the current laboratories, digestion NIRS method is widely used for this purpose. But this method has technical limitation. Therefor is important find appropriate method for estimate amount of amino acids. Artificial Neural Network (ANN) can provide a better reflection of the relationship between approximation feed composition and particular nutrient amount in that feed. Therefore, this study was performed to estimate amino acids corn and wheat by using artificial neural networks and multiple linear regression (MLR). In neural models used in the study, input variables include crude protein, crude fat, crude fibre, phosphorus and ash, and output variables includ profiles of amino acids relevant to combination of these two types of feed. The Results showed that there is a significant relationship Between amino acids in corn and wheat and its chemical composition. Also The statistical evaluation showed that the ANN model compared with MLR was a stronger estimation for prediction the amount of each amino acids. Hence the artificial neural network as a powerful tool for modelling, forecasting and estimating the nutrient composition of foods used poultry. Using the results of this study, it is recommended that artificial neural network can be used as a computational method with sufficient accuracy for modelling, prediction and estimation of the nutrient composition of foods used in poultry.

Lysozyme is one of the bioactive components of eggs with well known antibacterial potential، widely used in food industry، medicine and pharmaceutics. In this study، the possibility of quail’s egg lysozyme concentration and activity (modified via amino acids dietary supplementation) was investigated. In accordance with lysozyme amino acids profile، four amino acids of: asparagine، arginine، glycine، and methionine were added to layer quails’ feed. For supplementation of amino acids، provision of the same level of protein content in all the groups was considered، so that amino acids were supplemented in such a way as to add 0. 235% protein to the basal diet. A total of 72 Japanese quails were employed in a completely randomized design experiment of six experimental groups، three replicates and four birds in each of the 18 cages. Amino acids supplementation was proved to have significant increasing effect on egg number and on total egg،s mass production (P<0. 05). Feed conversion ratio did not significantly differ among the experimental groups، but the most desirable ratio was observed in the control group. Egg shell weight، percentage of albumen، percentage of yolk، albumen height، Haugh unit and yolk height showed significant differences among the experimental groups (P<0. 05). Supplementation of amino acids to the diet improved these parameters of eggs. Lysozyme activity was assessed via lysoplate and turbidity methods. Supplementation of arginine and asparagine alone and in their combinations increased the lysozyme activity as evaluated by lysoplate (P<0. 05) and by turbidity (P<0. 05) methods. Lysozyme concentration was also influenced by a supplementation of the mentioned amino acids (P<0. 05).