فصلنامه پژوهشهای تولیدات دامی
پیاپی 20 (تابستان 1397)

This study was conducted to evaluate the effect of different levels of herbal methionine in low protein diet on performance, carcass characteristics, immune response and some blood parameters in broiler chickens. In this experiment 240 day-old Ross 308 mixed broiler chicks were randomly divided into 6 groups with 4 replicates and 10 birds each in a completely randomized design. Treatments included: standard commercial diet with 100% synthetic methionine (DL-methionine) and low protein diet with different levels of herbal methionine (0, 15, 30, 45 and 60 percent) replaced with synthetic methionine respectively in grower (11 to 24 days of age) and finisher periods (25 to 41 days of age).Decreasing protein level significantly reduced feed intake in finisher and whole periods and reduced body weight gain in finisher period of the experiment (p<0.05). With increasing herbal methionine levels up to 60 % in low protein diet, feed conversion ratio significantly increased and body weight gain decreased in finisher and whole periods of the experiment (p<0.05). Decreasing dietary protein level, increased abdominal fat percentage and blood TG, cholesterol and VLDL concentrations at 41 days of age. Results of the present study indicated that herbal methionine could be replaced instead of synthetic methionine in low protein diet in grower and finisher diets of broiler chicks without any adverse effect on feed conversion ratio.

This experiment was conducted to evaluate the effect of graded dietary levels of pure curcuminoid on productive performance, egg quality traits, some biochemical blood parameters, immune response and its digestibility in the late phase of production of laying hens. A total of 160 sixty-weeks-old Hy-Line (W-36) laying hens were used in a completely randomized design, including 4 treatments in four replicates of 10 hens each. Dietary treatments diets contained 0 (control), 400, 800 and 1200 mg curcumin per kg of diet. Performance traits were assessed weekly and egg quality variables were measured bi-weekly. Adding curcuminoids to the diet caused a significant increase in production percentage (p<0.05). The hens receiving curcuminoid had more egg mass values. Changes in yolk color index as one of the internal egg quality traits were significant after the first week of experiment (P<0.05). Significant increase in ALT activity was observed in the group supplemented with 1200 mg in week 64 (P<0.05). In week 68, the ratio of HDL: LDL was significantly higher in the treatments that supplemented with 400 and 800 mg curcuminoids (P<0.05). Adding 400 mg curcuminoid resulted in the highest immune response and also the hightest amount of absobtion (P<0.05).using 400 mg curcuminoid changed yolk color improved immune response and decresed LDL and the highest level of obserbtion was also observed in 400 mg curcumioid.

In order to investigate the effects of Aqueous extract of phenolic compounds in green hulls of two varieties Pistachios green hull Kaleghochi and Fandoghi on performance and carcass characteristics, blood biochemical parameters and immune response of broiler, a total of 220 male day old chicks (Ross 308) were allocated to 20 experimental units in a completely randomized design with five treatments, four replicates and 11 birds each. Treatments were 0, 200 and 400 mg/kg of water extract of Kaleghochi and 200 and 400 mg/kg of water extract of fandoghi. Body weight, feed intake and feed conversion ratio were measured at the end of each of three nutrition periods including starter (0-10 days), grower (11-24 days) and end (25-46 days). Two birds of each replicate were slaughtered and bleed to measure the blood biochemical parameters and immune system at 24 and 46 days. Results were indicated that the body weight gain and feed intake were higher in 400mg/kg Kaleghochi pistachio hulls extract as compared to control. The FCR were decreased when birds fed 400mg/kg Kaleghochi pistachio hulls extract. There were no significant differences among treatments for relative weight of carcass organs except for abdominal fat. The both pistachio hulls extract decreased the abdominal fat, cholesterol, triglyceride, and LDL (P<0.05). The enzyme activity of aspartate aminotransferase was decreased when birds fed both pistachio hulls extract. The pistachio hull extract improved the immune response against SRBC as compared to control. It is concluded that supplementation of Kaleghochi and/or Fandoghi pistachio hulls extract may improve the performance, immune response, decrease abdominal fat and blood lipid profile of broiler chickens.

This experiment was conducted to investigate the effects of different sources of zinc on performance, egg quality, and immune system and blood parameters of Japanese laying quails. Total of 160 layer quails were allocated in 4 treatments include: 1) Basic diet as control, 2) Basic diet + 50 mg zinc/kg of diet from nano zinc oxide (n-ZnO), 3) Basic diet + 50 mg zinc/kg of diet from Availa-Zn as organic source (Availa-Zn) and 4) Basic diet + 50 mg zinc/kg of diet from zinc oxide as inorganic source (ZnO) in a completely randomized design with 4 replicates. Commercial traits included feed intake (FI) Feed conversion ratio (FCR) egg production; Egg quality charctresitics were weekly evaluated. Different sources of zinc didn’t show the significant effects on feed intake, haugh unit, egg weight and production (P>0.05). But Availa-Zn and n-ZnO improved FCR as compared to control (P<0.05). Eggshell thickness was higher in Availa-Zn group than other experimental groups (P<0.05). There were significant differences in yolk index, eggshell resistance and yolk color of n-ZnO versus control group (P<0.05). The toe web swelling reaction as the immune response was significantly higher in n-ZnO than control group at 24 hours post-injection of PHA-P (P<0.05). Different blood parameters of hepatic enzymes (alkaline phosphatase, alanine transferase, aspartate aminotransferase) and biochemical parameters (cholesterol, triglyceride, HDL, LDL) were not affected by experimental treatments (P<0.05). According to the results, it seems addition of Availa-Zn can improve the egg quality and performance of Japanese layer quails in comparison with the nano and mineral forms zinc supplementation.

This experiment was conducted to investigate the effect of ginger and nettle powders and their mixture in comparison with antibiotic growth promoter in a completely randomized design with 5 treatments, 4 replicates and 8 chicks per replicate in commercial broilers. The experimental treatments were:1) control (with no additive); 2) basal diet with 0.04% tetracycline antibiotic growth promoter (50% mixed in feed); 3, 4 and 5): basal diet with 1% ginger powder, 1% nettle powder and 1% of mixed ginger powder and nettle powder, respectively. The results showed that the highest weekly weight gain in the period of 21-35 days was related to the treatment group of 0.04% antibiotic growth promoter followed by the treatment group containing 1% nettle powder, which was statistically significant when compared with other dietary treatments (P< 0.05). In conjunction with the increased feed consumption in the period of 1-7 days of age, treatment groups with 1% ginger powder showed the highest value with statistically significant difference among other experimental groups (P< 0.05). In the sixth week of trial, treatment containing 1% ginger powder resulted in significant reduction in blood cholesterol levels compared to other experimental groups (P< 0.05). With regard to carcass characteristics, feed conversion ratio and other blood parameters no significant changes was noticed among all treatments in different week intervals (P>0.05). According to the archived results, ginger powder and nettle powder and their mixture can be considered as a relatively suitable alternative to antibiotic growth promoters for improvement of broiler performance.

Methionine is the first limiting amino acid in poultry which has a primary role in stimulating protein synthesis and growth. This study was designed to investigate the effect of dietary intake of different levels of DL-methionine on hatchability, carcass characteristics, and blood parameters of day-old Ross 308 broiler chicks. For this purpose, 240 fertile broiler breeder eggs were used in a completely randomized design with eight treatments and 30 eggs per treatment. The experimental treatments included injection of different levels of DL-methionine (0.19, 0.38, 0.57, 0.76, 0.95, and 1.14 %) dissolved in 1 ml sterile distilled water, along with a sham-control group (sterile water injection) and a control group (non- injected). After hatching, the chickens were weighed and blood samples were taken and slaughtered to measure carcass characteristics. In ovo injection of different levels of DL-methionine caused a reduction in hatchability (P<0.01), especially by 1.14 % DL-methionine treatment. Based on the results, in ovo injection of DL-methionine increased carcass weight, carcass yield, thigh weight, relative thigh weight, proventriculus weight, liver weight, and relative liver weight (P<0.05). In ovo feeding of DL-methionine increased serum protein concentration (P<0.01), whilst decreased serum glucose and urea concentration (P<0.01). Hatchling weight, serum cholesterol and triglyceride oncentrations, and also immune system organs weight were not affected by treatments (P>0.05). The overall results of the present study indicated that regardless of low hatchability in methionine treatments, in ovo injection of 0.76% DL-methionine had the best growth response and then, is an advisable level of this experiment.

In the present study, 30 multiparous close-up Holstein cows (average parity 3.8) were allocated in a completely randomized design with four treatments to evaluate the effect of chromium, monensin and their combination on blood metabolites and liver enzymes. Experimental treatments were: 1) control (no supplementation) 2) monensin (400 mg/d/h) 3) Chromium (0.03 mg/BW0.75) 4) combination of both supplements with similar dosages. Liver enzymes (AST and ALP) as well as the blood metabolites (glucose, BHBA, total protein, albumin) and insulin were evaluated. The results showed that blood parameters except that BHBA, glucose did not affect by treatment (p>0.05). BHBA concentrations in cows received chromium and its combination with monensin reduced before calving (p<0/05). Glucose concentrations was increased in cows supplemented with monensin (p<0/05). In conclusion, the results revealed that dietary combined supplementation of monensin and chromium may have positive affect on metabolism and energy status of multiparous close-up Holstein cows.

The objective of this study was to evaluate the effects of different doses of pistachio by-products (PBP) extracts on the protein protection from ruminal degradability in canola meals. PBP were extracted by four different solvents, i.e. 70% ethanol, 80% methanol, a mixture of chloroform and methanol, and water. Then, an in situ trial was conducted to determine ruminal degradability and disappearance (three head of castracted Taleshi male calves) and post ruminal (DaisyII incubator (of proteins in canola meal with 0.5 and 1 % tannins of PBP extracts supplementation. The total extraction of tannin contents with water, ethanol, methanol and mixture of chloroform and methanol extracts of PBP were 37.11, 9.64, 56.87 and 7.55 %, respectively. Canola meal supplementation with 0.5 % tannin from water and 1 % tannin from ethanol extracts decreased the protein ruminal disappearance (P < 0.01) without any negative effect on total gastrointestinal tract disappearance of protein. Also, the addition of 0.5 and 1 % water extracted tannin to canola meal reduced (P < 0.01) the ruminal degradability of rapidly degradable proteins. In conclusion, the results showed that tannins of water and methanol of PBP extracts could be effective on canola meals protein protection from ruminal degradability; however, the use of tannin from water extract of PBP can be more economical and practical.

The purpose of this study was to evaluate the effects of feeding probiotic and peribiotic supplements on milk yield, feed intake, fecal consistency and digestibility of Holstein calves. Treatments included: 1- control group (no additive milk) 2- probiotic group (milk + 2 gr probiotic) 3- prebiotic group (milk + 4 gr peribiotic) 4- synbiotic group (milk + 2 gr probiotic and 4gr perbiotic). Calves were weighed at the age of 3, 30 and 63 days after milking and feed intake weight was measured and recorded for every calves from the age of 10 days to the end of the period. For diarrhea, feces were observed weekly and feces score and fluidity were examined. At the end of the experiment (7 final days), the total stools of livestock were separately collected and weighed 20% sample was taken to investigate digestibility of nutrients. The chemical composition of fecal specimens and experimental diets including dry matter, fat, organic matter and protein were determined according to the AOAC method. The results of the experiment showed that the highest mean weight in the age of 30 and 63 days was related to the calves that used probiotics and had a significant difference with other groups. The lowest mean weight at the age of 63 was related to the synbiotic diet. The worst conversion ratio was in the control group and had a significant difference with the group that consumed probiotics. The best feed conversion ratio was probiotic diet and had a significant difference with other groups (P <0.05). The highest digestibility of dry matter and organic matter belonged to the group that consumed probiotics and had a significant difference with other groups. The lowest fecal consistency was in the group that consumed probiotics and had a significant difference with other groups (P <0.05). The lowest stool consistency was related to the group that used probiotics and had a significant difference with other groups (P <0.05). In general, the results showed that the use of probiotic had a significant effect on the performance, health and digestibility of Holstein calves.

This experiment was conducted to investigate the effect of oral administration and tissue injection of selenium and vitamin E on performance, blood metabolites and digestibility of nutrients in suckling Dalagh lambs. Eighteen lambs with 1-2 month age and the average weight of 13±2.7 kg assigned in a completely randomized design with three treatments and six replications. The treatments consisted of 1- control (without selenium and vitamin E), 2- tissue injection (tissue injections of selenium and vitamin E) and 3- oral administration (oral administration of selenium and vitamin E). The duration of the experiment was 84 days. Lambs were weighed every 14 days to evaluate changes in weight. In the first, 21, 42 and 63 days of experiment, blood samples were collected from the vein and samples were transferred to the laboratory. In order to determine digestibility of nutrients, sampling from feces was carried out in the last week of the experiment. The results showed that there was no significant difference between treatments in lambs performance (P<0.05). Iron concentration increased significantly in group receiving selenium and vitamin E compared to the control group (P<0.05). The concentration of triglyceride in injection treatment was significantly higher than that of control and oral administration (P<0.05). The supplementation of selenium and vitamin E in the form of injection and oral administration increased glutathione peroxidase activity in comparison with control group (P<0.05), and the use of selenium and vitamin E in the form of injection and oral administration showed significant difference in triiodothyronine and tetra iodothyronine hormone concentration (P<0.05). Blood glucose concentration increased in injection treatment compared to control and oral administration (P<0.05). The digestibility of nutrients did not show any significant difference among treatments (P<0.05). Overall, the results of this study showed that oral and injection use of selenium and vitamin E did not differ significantly in most of the parameters, and only glucose and triglyceride levels increased in the injection treatment compared to oral administration.

The aim of this study was to find the footprint of selection in native Sarabi and Taleshi cattle breeds 296 cattle from two breeds were sampled and genotyped. by 40 k microarray of illumine company. 43 animals were removed because their ACR was below 0.09. Markers were filtered with minor allele frequency (MAF) equal 0.01 and Hardy-Weinberg equilibrium test (10-6). After filtering, 28782 markers remained. To study the genetic structure of population and sub-population principal component analysis (PCA) was used. To identify selective signals for Sarabi and Taleshi pure population theta parameter was calculated. To reduce error theta values was averaged with near marker and Manhattans graph were obtained by haploview software. Chromosomes 2, 5, 6, 7, 10, 22, 25 and 27 had selection signatures. To searching for selection signatures in both population, extended haplotype homozygosity statistics (EHH) was calculated using R software. In addition, for each chromosome LD erosion rate for ancestral and mutant alleles were calculated. To study of positions that showed signature selection, bioinformatics web site were searched. EIF4G3 gene was identified on chromosome 2. This gene have fundamental role in transfering RNA from nucleus to the cytoplasm and gene expression. ANK2 gene was identified on chromosome 6 which encodes polypeptide ankirin B expressed in all tissues. On chromosome 7 the gene ARHGAP26 was found which is a tumor suppressor genes. On chromosome 10, a gene identified that encodes protein SYNJ2BP that suppress activing protein. On chromosome 22, FAM3D protein coding gene detected that plays a role in cyto sckeleton actin biochemical pathway. This gene is expressed in the placenta and plays a role in biological functions such as migration and function of leukocyte, temperature regulation, cell survival and hematopoiesis differentiation.

Ascites syndrome, also called pulmonary hypertension syndrome is a major concern of the poultry industry for decades. There have been a numerous reports regarding the underlying genetic variability of different breeds/strains in resistance against ascites. This scenario indicates gaining deep insight into the genomes of chicken pure lines, in order to find the favorable alleles within candidate genes controlling the variation of resistance/susceptibility to ascites. In this context, the aim of the present work to study the polymorphisms within STAT5B gene in the B line of Arian strain and to investigate the potential association of the confirmed polymorphism with body weight and growth rate traits at different ages as well as with carcass-related traits and ascites indicator traits. For this purpose, in overall, 166 birds, which their health status has previously been confirmed via clinical trials was chosen for genotyping the STAT5B gene in a polymorphic site using PCR-RFLP and MspI restriction enzyme. Enzymatic digestion results identified three AA, AG and GG genotypes with 0.46, 0.44 and 0.1 frequencies, respectively. Birds carried GG genotype were significantly (P<0.01) heavier in body weight (8-10%) or faster in growth rate (12-13%) than other genotypes all over of the rearing practice, particularly at 14-21 days of age. Furthermore, this genotype group was affected the heart weight considerably (P<0.10). However, there were no significant differences between the least square means of the remaining carcass related traits of the three genotypes. Moreover, the obtained outputs verified that there is no significant difference between the STAT5B genotype and allele frequencies between the healthy and ascites birds. Finally, it can be concluded that, the mutation of adenine to guanine substitution improves body weight and growth rate, but this polymorphism has nothing to do with ascites. This finding may emphasis to the fact that, despite the previous thoughts about the direct relationship of the genes controlling the ascites and growth, genes improving the body weight or growth rate do not have a direct influence in increasing the incidence of ascites. Further research is needed in order to be able to propose a general conclusion about the association of genes affecting the ascites and growth.

The main part of growth performance in birds is as a result of gene combination effects, which their changes require an optimal mating system in order to use general and specific gene combination ability. The purpose of the present study was to evaluate the growth patterns of four strains combination Japanese quail in a partial di-allele cross. For this purpose, four strains of Italian Speckled (A), Tuxedo (B), Pharaoh (C), A&M Texas (D) were used in a partial di-allele cross design to produce different gene combinations during four generations. Four functions including Gomperts, Richards, Logistic and Weibull were fitted for body weights records of different combinations. The best function for each combination was selected by goodness of fit criteria’s. Then, function parameters and growth patterns of the best function were compared between combinations. The results of goodness of fit criteria’s showed that the Gompertz function was the best one for binary combinations of AB, BA, CD, DC and reciprocal combination of ABCD-DCBA, DCBA-ABCD, while Weibul function was found to be the best function for quadrille combinations of ABCD, DCBA for describing growth curve. The effects of year and month of hatching on all growth patterns were significant (P<0.05). Also, the combination effect on initial weight, final weight, age and weight at inflection point and, one-day weight was significant (P<0.05). The effect of sex on curve growth parameters was not significant (P>0.05) except for 45-days weight. The DC combination had the highest initial and final weight, age and weight at inflection point compared to other combinations. The quadrille combinations, especially DCBA had the highest final weight, 45-days weight and, 45-days growth rate, but the lowest puberty index. Also, age and weight at inflection point in DCBA combination were at moderate level among combinations and showed better performance compared to other crosses indicating of the most heterosis in this combination.

In the present study two genetically connected small and large populations were simulated and the effect of different sources of information from foreign populations on the accuracy of predicted genomic breeding values of young animals of the small population was investigated. A large population consist of 200000 animals over 15 generations and a small population consist of 5000 animals over 3 generations were generated with QMSim simulation software in a such way that the small population was connected to the large one. Three scenarios were defined for estimating the accuracy of genomic evaluations based on various sources of available information. In the first scenario, the accuracy of genomic breeding values was estimated based on the genomic breeding values of individuals in the small population. In the second scenario, the accuracy of genomic breeding values of animals was estimated using the information of individuals in the small population accompanied with the genomic breeding values of male individuals from the large population. In the third scenario, phenotypic, genotypic and pedigree data of individuals from the large population were integrated to estimate the genomic breeding values of individuals in the small population. The averages for accuracy of estimated genomic breeding values were 0.34, 0.40 and 0.50 under the first, second and third defined scenarios, respectively. Furthermore, the averages for regression coefficient of prediction for genomic breeding values were 0.73, 0.83 and 0.93 under the first, second and third defined scenarios, respectively. The obtained results revealed that the integration of phenotypic, genotypic and pedigree information of both large and small populations had the most advantage for estimating the genomic breeding values of selected candidates in the small populations.

Genomic selection is a promising challenge for discovering genetic variants influencing quantitative and threshold traits for improving the genetic gain and accuracy of genomic prediction in animal breeding. Since a proportion of genotypes are generally uncalled, therefore, prediction of genomic accuracy requires imputation of missing genotypes. The objectives of this study were (1) to quantify imputation accuracy and to assess the factors affecting it; and (2) to evaluate the genomic accuracy of random forest (RF) algorithm to analyze binary threshold and quantitative traits. In the first phase, genomic data were simulated by QMSim software to reflect variations in heritability (h2 = 0.05 and 0.25), number of QTL (QTL=96 and 960) and linkage disequilibrium (LD=low and high) for 48 chromosomes. In the second phase, for real condition simulating, we randomly masked markers with 50% and 90% missing rate for each scenario; afterwards, hidden markers were imputed using FImpute software, and estimated imputation accuracy. In the third phase, to estimate genomic breeding values, we applied Random forest algorithm for original (before masking a proportion of SNPs) and imputed genotypes with quantitative and quality phenotypes. The accuracy of imputation was improved with increasing level of LD. With increase a major proportion of masked markers (90%), results of current study shed light on the effects of imputation accuracy on accuracy of genomic prediction. In the scenario combining the highest heritability, LD and QTL for threshold traits and in the scenario combining the highest heritability and LD and the least QTL for quantitative traits, random forest method had the best performance of genomic accuracy. Generally, accuracy of genomic prediction for threshold traits had more precise than quantitative trait when using the random forest method.