نشریه علوم دامی (پژوهش و سازندگی)
پیاپی 121 (زمستان 1397)

Oil sources could be fed in different forms in animal diets. The objective of the present study was to evaluate the effect of delivery method of soy oil in growing Holstein male calves. Eighteen growing Holstein bull calves (210±23 kg of BW) were randomly allocated in three different treatments with different delivery methods of soy-oil as follow; 1) dietary mixed soy oil (DMSO), 2) roasted soybean seed (RSB), 3) extruded soybean seed (ESB). The diets well balanced as isocaleric and isonitrogenous. The study lasted 10 weeks. Intake was recorded daily and weighing was done by monthly intervals throughout the experiment. Results show that performance parameters (intake, gain and feed conversion ratio) were not influenced with different treatments. Considering the blood metabolites results cleared that beta-hydroxy butyrate (BHBA) reduced in ESB treatment (P < 0=04). The TG concentration was increased in RSB treatment (P=0.01). Digestibility of nutrients also did not differ among treatments (P > 0.05). Delivery method of oil in diets did not influence chewing activity in Holstein calves. Results indicated that based on the experimental dietary fat level (39 g/kg DM), different delivery methods of soy oil may not influence growing calves’ performance and digestibility. Future research warranted to evaluate the delivery method of oil (fat) in higher levels in growing Holstein calves.

This study was conducted to investigate the characteristics and nutritional value of spent button mushroom compost (SBMC) silages prepared by soil removal and adding different levels of molasses in a completely randomized design. Firstly, the soil in a part of SBMC was removed by washing method. Treatments (1 + 5 treatments) were consisted of 1) SBMC without adding of molasses (control), 2) SBMC plus 7.5% molasses, 3) SBMC plus 15% molasses, 4) washed SBMC plus 7.5% molasses and 5) washed SBMC plus 15% molasses that ensiled for 60 days. Corn silage was used (as a typical silage) for comparison. Dry matter, chemical composition, lactic acid, total volatile fatty acids, water soluble carbohydrates and ammonia concentrations, pH, buffering capacity and flieg point in the silages were determined. Dry matter, organic matter, crude protein, NDF and ADF percentage before ensiling were 28.04, 55.59, 6.46, 29.69 and 27.01%, respectively for intact SBMC. Dry matter, crude protein and ADF percentage did not differ among the treatments after 60 days of ensiling (p>0.05). But, organic matter percentage increased in the treatments 4 and 5 (65.51 and 61.85%, respectively) compared with the control (p<0.05). The treatment 5 had the lowest pH (5.16) and highest lactic acid concentration (15.80 g/kg DM). The fleig point was highest in treatment 5 (66.56). Generally, the soil removal and adding 15% molasses into SBMC, improved the nutritional value of its silage.

The aim of this experiment was to determine the effects of anise and angelica extracts (200 mg/kg) in comparison with antibiotics oxytetracycline (200 mg/kg) and probiotic Primalace® (100 mg/kg) on immune response, ileal microflora and jejunal morphological characteristics of broilers. A total of 400 Ross 308 broiler chicks were assigned in a completely randomized design to five experimental treatments. Each treatment consisted of 4 replicates and 20 one-day old chicks per replication. The evaluation of immune response of chicks was conducted by injecting 5% SRBC suspension, assessment of ileal microflora by removing the ileum contents of the birds and examination of jejunal morphological characteristics by cutting the middle part of the jejunum after slaughter. The results of this study showed that experimental treatments had no significant effect on antibody titer against SRBC. The frequency of heterophils and heterophile to lymphocyte ratio decreased significantly affected by anise and angelica extracts (P<0.05). The total population of aerobic bacteria, Escherichia coli and Coliform bacteria decreased significantly by angelica extract (P<0.05). All treatments containing additive caused significant increase in jejunum villus height when compared to control treatment (P<0.05). The villus height to crypt depth ratio in jejunal was significantly increased by anise and angelica extracts (P<0.05). Generally, the results of this experiment showed that the use of anise and angelica extracts by amount of 200 mg/kg diet may improve immune response, reduce the harmful ileal microflora and improve jejunal morphological characteristics of broiler chickens.

The aim of this study was to evaluate the expression of pancreatic Charboxypeptidase gene and changes of pancreas weight of broiler chickens fed with different levels of oak acorn. For this purpose, three diets (control, 15% and 20% oak) were fed to broilers from 1 to 42 days of age. On days 21 and 42, body weight and pancreatic weight of 36 broiler chicken (18 for each time, 6 for each treatment) were measured. Then the total RNA extracted from the pancreatic tissue and cDNA was synthesized. The gene expression analysis is also fitted with the REST, 2009, and SAS 9.1 softwares. The gene expression results show that mRNA expression levels of Charboxypeptidase gene were significantly higher in treatment containing 15 percent oak acorn on day 21 in compared to those fed with diet without oak acorn (p<0.05). On day 42, the expression of Charboxypeptidase gene in chickens fed with diet containing 20% oak was significantly lower in compared to 15% oak diet (p<0.05). In addition, pancreatic relative weight was significantly increased in broilers fed with diet containing 20% oak on day 42 (p<0.05). Generally, the substitution of dietary corn with oak acorn lead to a change in expression of Charboxypeptidase gene, reducing body weight and an increase in the relative weight of the pancreas, and these effects depend on the value of DMI, the percentage of oak acorn, time period of its use and other factors .Hence, in order to understand the molecular mechanism polyphones function requires more research.

This study was conducted to evaluate the effects of different levels of dietary crude protein (CP) and threonine(Thr) on nutrient digestibility and blood parameters in Nicholas turkeys.A total of 160 male turkeys (Nicholas 300) with 4wk of age were randomly assigned to 10 treatments with 4 replicates in 2×5 factorial arrangement. Experimental treatments including two different CP levels (26 and 23.4%) and Thr in 5 levels (0.75, 0.85, 0.95, 1.05 and 1.15% of diet). Results showed that reducing the level of CP in the diet reduced fecal digestibility of dry matter and organic matter(P<0.05), However,there was no significant effect on illeum digestibility.Level of 1.05% of threonine improved illeum digestibility of crude protein and fecal digestibility of dry matter and organic matter (P<0.05). There was an interaction between levels of CP and threonine for the nutrient illeum digestibility(P<0.05). Reducing of levels of CP significantly decreased albumin and uric acid concentration (P<0.05), However, diet CP concentration did not have significant effect (P>0.05) on other blood parameters.Levels of 0.95 and 1.15% of Thr significantly increased serum total protein and globulin levels compared to other Thr concentrations (P<0.05). Levels of 1.05 and 1.15% of Thr decreased albumin concentration and albumin/globulin ratio(P<0.05), Although Thr had not significant effect on glucose,uric acid,cholesterol, triglyceride,HDL,VLDL and LDL concentration(P>0.05).The findings of this study showed that reducing the level of CP, decreased nutrients digestibility and serum uric acid and increased levels of Thr in the diet improved fecal nutrients digestibility and increased serum protein and globulin levels in commercial turkeys

Genomic data can lead us to how of breeds and populations forming and process of genetic occurrences effecting even infrequent cases of them at time passage. A very worthy instance to genetic resources preservation that itself is counted an important subject, and improvement of animal breeding plans, is genetic structure discovery of studying populations. For investigation about genetic structure homogeneity in Zandi breed sheep population located in Tehran Zandi sheep breeding station, discriminant analysis of principal components (DAPC) and in inside of this analysis, principal components analysis (PCA) were performed. For this purpose, 99 heads of sheep were bled and genotyped using Illumina SNP chip 50K. Discriminant analysis of principal component obviously showed the genetic structure of studying population and its members separation to two groups that it may be arising from DAPC high sensitiveness that is able to investigate variance homogeneity in animal populations. In DAPC, to evaluate the clusters optimized number using BIC, k=2 was shown as best result. Investigation of results to maintain the number of principal components for discriminant analysis, takes into account that the first 31 components is the optimized number of component for analysis next steps. Re the importance of within group variance contemplating and also populations genetic structure for important genomic analyses, became clear that DAPC in study of Zandi population genetic structure, because that contemplates of more principal component number and subsequently increasing of contemplated variance, is more effective than PCA.

The aim of this study was to determine the effects of Zn-methionine (Zn-Met) and Zinc sulfate (ZnSo4) supplementation on growth performance, carcass characteristics, serum zinc and copper and zinc concentrations in some tissue i.e. length, weight, internal and external offal items in Sanjabi lambs. All lambs were slaughtered at end of fattening period and biometry of carcass was determined, also zinc concentration in five carcass tissues were analyzed. The results showed that ZnSo4 supplementation reduced dry matter intake, final body weight, carcass weight without fat-tail and carcass length as compared to the control group (P<0.05). The hind leg and fore leg length increased in the Zn-Met group (p=0.001). The Zn concentration of Quadriceps femoris and Longissimus dorsi were not significantly affected by organic and inorganic Zn supplementations, however, pancreas, lounges and heart concentrations of Zn were higher (P<0.01) in organic Zn groups as compared to other groups. The Zn concentration of feces showed that zinc sulfate bioavailability was lower compared to the Zn-Met group (p=0.001). The concentrations of Zn and Cu of serum were not affected by Zn supplementation in treated lambs (P> 0.05). The result of this study showed that zinc sulfate supplementation reduced lams growth and DMI, however feed efficiency ratio was not affect by treatments. The Zn-Met was not affected on growth of lamb, however the lounges and heart Zn concentrations increased.

This study investigates the price relations between producer and consumer level in the Iran fluid milk market. We applied a Markov-switching vector error correction model on the monthly price data from March 2003 to December 2015 to allow for multiple regime shifts in the relationship between farm and retail prices. A model with two regimes with three lags has finally been chosen and estimated. According Granger Causality Test there is one side causality relation from producer’s price to consumer’s price. Results show that second model, points to data that relates to 2003 until 2006 and also, 2013 to 2015; whereas, those following first model, refer to 2007 till end of 2012. Thus the type of relationship between two series is different depend on policy actions that government adopts during the times. Main results show existence of a positive price asymmetry in the market. In the long run price transmission is perfect, while in the short run price adjustment between two market levels is asymmetric. On the other hand, retailers benefit from any shock that affects supply or demand conditions.

Streptococcus bovis has been considered to be one of the starch utilizers and lactate producers in the rumen. By considering the role of S. bovis as main lactic acid producer, a large amount of biological information about this strain has been published. But there has not been a systematic analysis of metabolic capabilities for S. bovis so far. In the present study, the first genome-scale metabolic model of S. bovis (iStr472) was reconstructed based on the genome annotation of S. bovis B315. The model was analyzed in terms of sensitivity, topology and capabilities for utilization of other substrates. Results revealed that iStr472 comprises 694 reactions, 626 metabolites and 472 genes. The majority of reactions were located on the nucleotides metabolic pathway. The metabolic genes of model estimated as 27.6 % of all coding genes. Comparison of two models (iStr472 and ModelSEED) indicated that iStr472 has a higher accuracy and validity than the ModelSEED. The 16 highly connected metabolites were found in the model. The results of reaction deletion presented that the model has 126 vital reactions essential for the organism's growth. According to the model prediction, production of biomass was inversely influenced by lactate production. The iStr472 is also capable of utilizing fructose as carbon source. Taken together, it would be possible to use the predictions of iStr472 as a tool for better understanding the metabolism and metabolic engineering of S. bovis for reduced lactate production in the rumen.

Body weight is one of the important economic traits in the breeding program of broiler species. The genetic parameters of each population are affected by different environmental conditions. Therefore, each breeding activity in a poultry is required to estimate these parameters. The aim of this study was to estimate the genetic parameters of body weight from hatch to 45 days old of the crossbred population of Japanese quail by using of 1794 records of body weight from 70 males and 72 females. Estimation of genetic and non-genetic parameters was performed using a multi-trait model including additive, non-additive and maternal effects via Gibbs sampling. Estimated heritability for body weight in hatch, 5, 10, 15, 20, 25, 30, 35, 40, and 45 days’ was 0.16, 0.11, 0.12, 0.14, 0.15, 0.18, 0.20, 0.19, 0.17 and 0.17, respectively. The range of heritability for maternal genetic, the ratio of maternal permanent environmental, dominance, and epistasis variance to phenotypic variance varied between 0.32-0.39, 0.23-0.36, 0.04-0.10, and 0.03-0.13, respectively. The highest value for genetic correlation was estimated between body weight in 35 and 30 days (0.94) and the lowest value was between hatching weight and 5 days (0.16). The results showed that the maternal and non-additive effects must be fit into the model for accurate estimation of genetic parameters, and the selection of quail for body weight of 25 days due to its high correlation with 45 days and its high heritability could result in a good genetic improvement in the body weight of 45 days.

The aim of this study was to compare the Wood, Dijkstra and Sineus models for fitting the lactation curve of the first abdomen of Khuzestan Buffalo. The effect of fix factor such as year, season and herd on the curve of milk parameters were studied. In this study, 73169 test day records of milk were used. Records were collected in the animal breeding center. According to the test day record and using different initial values, using SAS software and NLIN procedure were estimated the parameters of each lactation models. R2adj, AIC, MSE, RMSE and Iterations were used for comparison of models. The results of the model's comparison were showed that all three models of Wood, Dijkstra and Sinus were able to fit the buffalo curve. But the Wood model, having the lowest AIC, MSE and RMSE was goodness than the other two models. The mean of Wood parameters such as a, b and c were 2.36, 0.656 and 0.0009 were respectively. Average the peak of lactation was 84 days. The most and least lactation continuous was in summer and spring, respectively (p<0.05). All Wood parameters and lactation indexes were affected year, herd and their interaction (p<0.05). By using the lactation curve and determining the components of lactation, it is possible to plan for feeding and management of buffaloes.

For evaluation the effects of different levels of crystalline amino acids supplemented in the diets with different protein quality on performance, energy and protein efficiency, carcass components and intestinal morphology, where, experiment conducted with completely randomized design by 2×4 factorial. In this experiment were used 576 Ross 308 (mixed) broiler chickens with 6 replicates (12 chickens per each replicate) on starter, grower and finisher periods. Experiment diets have been including maize-soybean meal (as high quality protein source) and wheat-canola meal (as low quality protein source) and four levels of crystalline amino acids (recommended levels, 0 or without supplemented crystalline amino acids, 10 and 15% higher than the recommended levels of DL-Methionine, L-Lysine, L-Threonine and L-Tryptophan) by broiler Ross 308. The results of this study showed that the use of adjusted diet based on soybean meal and the recommended level related to other treatments, were causes to increase the energy and protein consumed and also the feed intake and body weight at finisher period. On the other hand, the results showed that adding amino acids crystalline 10 and 15% higher than the recommended levels to diet containing canola meal and wheat as a low-quality source caused an increase on energy and protein consumption, thus reduced energy and protein efficiency and an increase on feed intake and weight gain at finisher period. Interactions between diets with different protein quality and different levels of crystalline amino acids also did not show significant differences on carcass components and intestinal morphological traits.

The present experiment was conducted to determine the effect of different amounts of olive pulp replaced with barley grain in the diet of sheep, on whole microorganisms or bacteria activity isolated from their rumen, in digestion of wheat straw (fiber feed source) or soybean meal (protein feed source). The experiment was conducted with 12 Arabi male sheep (weight 33 kg) in a completely randomized design. The experimental treatments were the liquor taken from rumen of sheep fed three diets containing: 1- Control (without olive pulp), 2- 7.8 and 3- 15.6% of the olive pulp. Potential of gas production of wheat straw that was incubated by isolated bacteria from rumen fluid of sheep fed with diet contain 15.6% olive pulp, decreased significantly in compared to control (76.92 vs. 47.48 ml). Organic matter digestibility of wheat straw by whole microorganisms of sheep fed with diet containing 7.8% olive pulp was increased in compared to the control diet (21.12 vs. 30.90%). Gas production rate of wheat straw and soybean meal fermented with rumen fluid of the sheep fed diet containing 7.8% olive pulp was maximum amount among all diets (0.017 and 0.05 ml/h, respectively). Partitioning factor (PF), the efficiency of microbial biomass, and cell wall degradability of wheat straw incubated by isolated bacteria from the rumen fluid of sheep receiving diet contain 15.6% olive pulp were lower than other diets.

In this experiment, the effect of vitamin E (VE) and selenium (Se) combination and vitamin B12 (VB12) and iron (Fe) combination injection investigated on antioxidant status and health of transition dairy cows. Twenty heifers and 20 multiparous Holstein cows were divided to 4 balanced groups accoding to parity and BW. Experimental treatments consisted of 1) injection of 7 ml of NaCl % 0.9 (Control), 2) injection of 60 ml of VE and Se, 3) injection of 7 ml of VB12 and Fe and 4) injection of 60 ml of VE and Se with 7 ml VB12 and Fe. Solutions injectied on 21 and 7 day before calving and 7 d postpartum. Injection of VE and Se increased serum VE concentration and total antioxidant capacity (TAC) at calving day and day 7 and 14 postpartum, serum Se concentration and glutathione peroxidase activity at calving day and 14 day postpartum and blood neutrophils counts at calving day. Serum VB12 concentration at all sampling times, serum Fe concentration and catalase activity at calving day and serum TAC at calving day and day 7 and 14 postpartum were higher in cows received VB12 and Fe combination. The greatest incidence of retained placenta and mastitis were observed in control group. Overally, although, simultaneous injection of VE, Se, VB12 and Fe had no significant effectat on antioxidant status of transition dairy cows, but there is no observation of retained placenta and mastitis incidence in this group.

Efficiency is a concept that determines the input and output ratios of an economic system. Data Envelopment Analysis (DEA) method is a useful tool for estimating the efficiency of a unit. The purpose of this study was estimation of economic efficiency and determining of return to scale of broiler production units in Gilan province. Therefore, the information includes the day old chick price, the cost of manpower, the cost of feed, the cost of health and treatment, the cost of fuel (gas, gasoline and electricity) of thirty commercial broiler production units in Gilan province collected and the efficiency was measured based on production and economical function. Then, the technical and allocative efficiency was estimated to calculate the economic efficiency. Based on these results, based on costs minimization, the average of technical, allocative and economic efficiency in constant returns to scale condition was 96.7, 91.8 and 88.7 percent, respectively and in variable returns to scale condition was 97.5, 94.0 and 91.6 percent, respectively. Also, the average of scale efficiency was 99.2 percent. According to results of DEA method, it is recommended the farms with capacities of 5000 to 30000 chicken, the 25 days interval among production cycles, and the proposed models should be used to increase the efficiency of commercial broiler production units in Gilan.

The aim of this study was to investigate the concentration of Prussic acid and Nitrate as main anti-nutrients in 18 varieties of sorghum forages. The sorghum varieties include four domestic Iranian sorghums named: Pegah, Speed-feed, KFS-2 and KFS-18 and 14 imported varieties named: CSSH.1, FGCSI09, FS 1 BMR, JS BMR SSH.1, JS BMR SSH.2, S, T, PHFS-27, PFS-21, FGCSI10, FGCSI12, SP BMR, HFS1 and JS 2. All sorghum varieties were cultivated in the farm of Seed and Plant Improvement Institute. General condition such as irrigating, fertilizing, light and temperature were the same for all varieties. Samples were harvested at blooming stage and concentration of prussic acid and nitrate was determined. Statistical analysis was performed using one-way ANOVA. The highest concentration of prussic acid detected in FS 1 BMR (481 ppm) PHFS-27(408 ppm) and FGCSI10(381 ppm). and the highest concentration of nitrate was detected in JS 2 (2416ppm) and JS BMR SSH.1(2088 ppm). By comparing the concentrations of prussic acid and nitrate in these 18 varieties of forage sorghum with the tables of anti-nutrition hazard level, it was found that the concentration of anti-nutritional substances in all of these varieties was lower than the level of dangerous for livestock.

This study was conducted by 360 lying Japanese quail (6 wk old) in a 3*3 factorial arrangement (9 treatments and 5 replicates each) to investigate the effects of folic acid (0.0, 4.0 or 8.0 mg/kg) and pyridoxine (0.0, 0.3 or 6 mg/kg) on laying performance and egg yolks 5-methyl tetrahydrofolate content. The results showed that folic acid or pyridoxine had no effects on feed intake, egg production, feed conversion ratio, yolk and white percentage, egg content weight and haugh unit of the eggs (P>0.05).The 5- methyl tetrahydrofolate content of the eggs was affected by folic acid supplementation and it was increased from 808.62 microgarm/g for control birds to 840.84 and 1164.77 microgarm/g respectivly for 4 and 8 mg/kg folic acid fed birds (P<0.01). In conclusion, dietary supplementation of folic acid to lying Japanese quail diets had no effects on performance but consumption of 8 mg/kg folic acid increases the 5-methyl tetrahydrofolate content of yolk.

Betaine is a methyl group donor that can affect important physiological processes involed with hemocyctein such as lactation. In the present study, the effect of betaine supplementation on concentrations of some blood metabolites, and on quantity of colostrum in pregnant ewes was investigated. Twenty multiparous pregnant Sanjabi ewes were fed either a basal diet (Control: 71.2±3.6 kg BW) or the basal diet supplemented with 5 g per kg dry matter betaine (Betaine: 71.6±3.8 kg BW) during the last month of gestation. Feed intake, body condition score, udder volume, and circulating concentration of glucose, beta-hydroxybutyrate, albumin, total protein, urea and homocysteine were determined during the last month prepartum. The quantity of colostrum was measured in two times with oxytocin ingection until six hours post- partum, and then was analysed for its chemical composions. The dry matter intake, body condition score, and udder volume of ewes in both Control and Betaine were similar. Quantity of colostrum (593 vs. 365 g) and fat (93 vs. 59 g), and blood concentration of hemocystein (8.4 vs. 8.1 µmol/L) in ewes receiving betaine was greater (P <0.05) than those in Control. Ewes in Betaine had a tendency towards lower circulating concentration of glucose (3.2 vs. 3.4 mmol/L, P=0.098), and beta-hydroxybutyrate concentration (0.46 vs. 0.82 mmol/L, P=0.059) than control ewes. In conclusion, dietary supplementation of betaine increased quantilty and fat content of colostrum, increased circulating hemocystein, and reduced circulating ketone bodies most likely via suppresing fatty acid oxidation in Sanjabi pregnant ewes.

Genomic technologies, such as high-throughput genotyping based on SNP arrays, have great potential to decipher the genetic architecture of complex traits and provide background information concerning genome structure in domestic animals, including the extent of linkage disequilibrium (LD). In this study, Illumina OvineSNP50 BeadChip array was used to estimate and compare LD, effective population size (Ne) and heterozygosity in three Iranian sheep populations consisting Afshari (N=41), Moghani (N=35) and Qezel (N=35) breeds. The average LD (measured by r2) estimated for all pairwise combinations of SNPs with average distance 58, 56 and 56 Kb were 0.151 ± 0.207 for Afshari, 0.131± 0.190 for Moghani and 0.121 ± 0.148 for Qezel breeds, respectively. The highest averages of r2 on autosomes were obtained for chromosome 2 in Afshari and Qezel and chromosome 12 in Moghani breeds. The Qezel breed showed highest genetic diversity based on effective population size and heterozygosity, whereas the lowest value was found in Afshari breed. Due to low LD values estimated in this study, the results showed to achieve the genomic prediction accuracy of 85% in genomic selection and association studies, the density of marker must be higher than 50K SNPChip.

Fatty acid synthase (FASN), a multifunctional protein that carries out the synthesis of fatty acids, is coded by FASN gene which is known as major candied gene and plays a central role in de novo lipogenesis in mammals. This study was conducted to detect single nucleotide polymorphisms (SNPs) of the FASN gene and explore their relationships with three economically important traits including milk production (M), calving interval (CI) and conception rate (CR) in Holstein cows of Kerman province. The whole blood samples corresponding to the 38 Holstein cows with high and low estimate breeding values were collected. Genomic DNA was extracted from blood samples of the cows using a genomic DNA kit according to the manufacturer’s instructions. The genetic material was used for polymerase chain reaction amplification of selected gene fragments (750bp length from exon 37 to 39). All of PCR products were subsequently used directly for sequencing. Analysis of the target sequence followed by multiple regression of average allele substitution effects on M, CI, and CR traits revealed 58 SNP markers, among which 8 SNPs were totally associated with productive and reproductive traits. (M), (CI) and (CR) were affected by three (g.16593A>G, g.16670C>A and g.16776C>T), three (g.16524G,C,T>A, g.16830G,C,T>A, g.16833A,T>G) and two (g.16594A,C>G and g.16811A,T>G) SNPs respectively (P<0.05). Association between polymorphism in FASN gene and traits could be used as molecular markers for determination of animal's genetic potential as well as breeding strategies in Holstein population.

This experiment was conducted to evaluate the effect of electron irradiation (EI) and fibrolytic enzyme (FE) on chemical composition and rumen degradation of palm leaves (PL) in a completely randomized design with factorial (2×2) arrangement include 2 levels of irradiation ( 150 and 300 KGy) and enzyme (1.5 and 3 gr/kg dry matter of samples). For this purpose, at first 5 g of milled sample was incubated for 2, 4, 8, 12, 24, 48, 72 and 96 hours in the rumen of two Sistani bull with rumen fistula and degradability parameters estimated using nylon bags method. Based on the results, The EI and FE had no significant effect on dry matter, ether extract and crude protein. Treatment separately and together caused a significantly decreased (p<0.01) NDF and ADF. Also, the rapid and slowly degraded fraction and effective degradability of dry matter significantly increased with increasing irradiation dose and enzyme levels (p<0.01). EI along or with the FE had an effective role in improving the nutritional value and degradability of palm leaf. Considering that the best results were obtained in the simultaneous use of EI of 300 KGy and 3 g/kg of FE, the simultaneous use of these two levels were effective in order to improve the digestibility and degradability of palm leaves.

This study was conducted to evaluate the effect of diets formulated based on Arian and Ross broilers catalogues on performance and carcass characteristics of these two strtains. In this study, a total of 640 one-day old Arian and Ross broilers were used in a 222 factorial trial (two strainstwo sexestwo diets) in a completely randomized design, with 4 replications and 20 chicks in each replication. The results showed that at the entire experimental period (49 day of age), body weight gain (BWG) and European Efficiency Factor (EEF) of Ross chicks were significantly (P<0.05) higher and their feed conversion ratio was significantly (P<0.01) better than those of Arian chicks. Feed consumption, BWG and EEF of Arian and Ross chicks fed diets formulated based on Arian catalogue were significantly (P<0.01) higher than those fed diets formulated according to Ross catalogue. Carcass and breast meat percentages of Ross chickens were significantly (P<0.05) higher and their abdominal fat and viscera percentages were significantly (P<0.01) lower than Arian chickens. Energy and protein consumption per kg total BWG and carcass yield and also the total feed cost per kg BWG and carcass yield of Ross chicks were significantly (P<0.05) lower than Arian chicks. However, the feed plus chick cost did not have any significant difference. It seems that Ross broilers have better productive characteristics, compared to Arian broilers, but formulation of the diets based on the Arian catalogue (longer utilization of starter and grower diets) would improve the performance of both Arian and Ross broilers.

Forage amaranth (var. Maria) and corn were ensiled in plastic bags, for a period of 60 days, with 5 replicates. Chemical composition, oxalic acid, nitrate and phenolic compounds of the samples were measured. In vitro ruminal fermentation and ME were determined using a gas production method, and in situ degradability by nylon bags using 3 fistulated rams. Crude protein were 80 and 199 g/kg DM for fresh corn and amaranth, and 75 and 180 g/kg DM for ensiled corn and amaranth, respectively, which indicate higher (P<0.05) protein in fresh and ensiled amaranth compared with corn. Forage corn was contained higher DM, WSC and NDFom in comparison with amaranth, while ash was greater in amaranth (P<0.05). The pH of corn and amaranth silages was 3.8 and 4.1, respectively. The amounts of nitrate, oxalic acid, total phenolics and total tannin in corn silage were lower than amaranth silage (P<0.05). In vitro organic matter digestibility, ME and effective degradability of ensiled amaranth were lower (P<0.05) than those in corn silage, but microbial protein and metabolizable protein were greater (P<0.05) in amaranth silage. Overall, nutrients composition and fermentability parameters of amaranth (var. Maria) were comparable to corn silage, with higher crude protein content. Amaranth can be preserved as a valuable silage to feed ruminants in arid area.