نشریه علوم دامی (پژوهش و سازندگی)
پیاپی 119 (تابستان 1397)

The objective of this experiment was to study the effects of two levels of barley silage particle size and two types of grain, barley and maize on feed intake, nutrients digestibility, rumen parameters and feeding behaviors in sheep. Statistical analysis was conducted using the changeover design experiment. Whole-plant barley was harvested at 28±1.5% moisture in 8 and 16 mm theoretical chop lengths for prepering short- and long- silages. Four male kermani sheep with the average weight of 53.38±2.05 kg were used and Experimental diets were: 1) long barley silage and barley grain 2) long barley silage and 20 percent corn grain 3) short barley silage and barley grain 4) short barley silage and 20 percent corn grain. Dry matter intake was influenced by the type of grain and was higher in diets that contain 20 percent corn grain (P<0.05). Rumen pH was affected by barley silage particle sizeand 2 types of grain, at 2 and 4 hours after feeding and was higher in long barley silage and 20 percent corn containing diets (p<0.05). Ammonia nitrogen concentration in rumen and microbial nitrogen and protein synthesis weren't influenced by treatments (p>0.05). Feeding behaviors, were affected by barley silage particle size, but did not affect by grain type. Dry matter intake was increased in 20% corn grain diets, due to increased pH and better rumen environment.

This study was conducted in order to evaluate the effect of Thyme (Thymus vulgaris L.) essential oils on performance, carcass characteristics, serum metabolites and immune response in broiler chickens under heat stress. A total of 400 male broilers (Ross-308) were divided into 4 treatments with 5 replications of 20 birds per each. Experimental treatments were as follow: Control diet without additive and diets containing 0.1, 0.15 and 0.2 % of thyme essential oil. The results showed that supplementation of diet with thyme essential oils had not significant effect on average body weight daily weight gain, daily feed intake, feed conversion ratio, carcass characteristics (P>0.05). Addition of thyme eesential oil to broilers diet not influenced (p>0.05) serum metabolites (gluose, albumin, protein, triglyceride and VLDL), However significantly decreased (P<0.05) serum cholesterol and LDL concentration and significantly increased (P<0.05) HDL concentration. Supplementation of diet with thyme essential oils significantly increased (P<0.05) antibody response versus ND disease and sheep red blood cell (SRBC) in broiler chicks under heat stress. These results suggested that supplementation of diet with thyme essential oil tended to increase growth rate, immune system reinforcement, decreased serum LDL and cholesterol, and these could be consider as a growth promoter immune response amplifier in broilers diet under heat stress.

Different compounds such as soy lecithin have been used in the sperm freezing of different species. Repeated freezing was less considered in farm animals and doing this proccess could be valuable for the rare breeds. Inorder to investigate the effect of lecithin and glycerol on sperm quality in repeated freezing and thawing, frozen bull sperm straws were thawed and the previous diluent eleminated. Then, the sperms were diluted in Tris buffer freezing extender containing different concentrations of glycerol (3, 5 and 7%) and soya lecithin (1% and 2%) and were frozen again. After two weeks, the sperms were thawed and sperm characteristics were evaluated immediately after thawing and up to two hours incubation at 40 °C. The results indicated that treatments containing 5% glycerol with one percentage lecithin (G5L1) and 3% glycerol with 2% lecithin (G3L2) had the highest and the lowest percentage of motility, viability and membrane integrity of sperm, immediately after thawing and one hour incubation at 40 °C respectively. The percentage of motile and viable sperms in G5L1 treatment was significantly higher (P <0.05) than the control group after 2 hours of incubation at 40 °C but sperm membrane integrity did not have significant difference with the control group (P>0.05). In general, the results showed that using 5% glycerol with 1% can improve the sperm characteristics in repeated freezing and thawing.

The effect of energy expression system and total amino acid database on growth performance, carcass components and litter quality of Ross 308 broilers strain was studied by 180 broiler chicks in a completely randomized design with a 2×3 factorial arrangement. This study was performed with six treatments, three replicates and ten broiler chicks in each replicate. Treatments expression was with two systems of energy (AMEn and TMEn) and three amino acid database (NRC, Evonik and Ajinomoto) in periods starter (1-10 days), grower and (11-24 days) finisher (25-42 days). Apparent metabolizable energy corrected for nitrogen in the dietary formulation caused a relative increase in feed intake and weight gain of broilers in the grower and whole period of experiment (1-42 days). Energy system had no significant effect on feed conversion ratio, protein and energy utilization, carcass components and litter quality (P>0.05). Evaluating feed conversion ratio, efficiency of energy and protein utilization, European production index during total experiment period showed that NRC and Evonik amino acid databases were significantly better than Ajinomoto (P<0.05). Based on the current results, it seems that NRC and Evonik amino acid databases, in the condition of current experiment have relatively some advantage compared to Ajinomoto database.

Today, exiting of high relationship and overlap between bioinformatics science and molecular biotechnology, can be play important role in genetic improvement of production traits. Growth trait is one of important production traits in animal husbandry, it affected via several biological pathways. Identification of the biological pathways is available using expression gene profiles and genomic information, and can cause of expand systemic idea about of the complicated procedure and better understand. In the study, collected data information about of gene expression in muscle tissue in two group cow 1 month and 24 month, from data base of Array Express. In first step investigated difference between expression genes using ArrayAnalysis, candidate 2732 genes for identifying biological pathway. Analysis of biological pathway conducted by PathVision software. Results of study gene expression in two group show that in two treatments, 503 gene had increasing in expression and 411 gene had decrease in expression. Study morphophonemic of the genes show that the genes play role in 23 biological pathways, most of the pathways play role in cellular process as growth, proliferation, differentiation, homeostasis and death was scheduled. The results can be lead to identification biological markers candidate for growth trait, that is a positive step forward to improve of procedure of cattle genomic evaluation and selection.

The objective of the present study was to investigate the preservative effect of green tea extract as a natural antioxidant on sperm quality parameters of rooster in the duration of an entire spermatogenesis cycle. Sixteen rooster divided into four aliquots and consumed diets supplemented with 0, 30, 60, 90 mg of green tea extract/kg of feed. On 0, 14, 28, 42, 56, 70 days after start semen fluid were collected and CASA for sperm motility, progressive motility, linearity (LIN), curvilinear velocity (VCL), amplitude of lateral head displacement (ALH), average path velocity (VAP), straight line velocity (VSL), nonapoptotic sperm and DNA fragmentation (by staining sperm with acridine orange). Treatments 3 and 4 reduced apoptotic sperm and improved some of sperm motion parameters such as ALH (P<0.05). However, in last days of experiment, treatment 4 had adverse effects on VAP and VSL (P<0.05). The least amount of green tea extract (30 mg/kg of feed) improved VAP (P<0.05). The results showed that daily consumption of 60 mg green tea extract/kg of feed, as a natural antioxidant, could possibly lead to improve some of sperm motion parameters and reduced apoptosis.

Arasbaran region have high potential in beekeeping because of climatic conditions, high access to water, and high flora diversity. The purpose of this research was to examine the income and problems of rural beekeepers in the path of development.The research data were collected using field observations and semi-structured questionnaire from beekeepers of Arasbaran region. At this study, we will examined the type of species used by honeybee in terms of beekeepers, the process of selling products, the role of beekeeping in household income, the main problems of beekeepers, and the development strategies of this industry. Suitability of beekeeping sites was considered based on four criteria. Some of species were used for honey and propolis production such as Thymus kotschyanus, Verbascum gossypinum, Cirsium arvense, Astragalus spp, Salix babilonica, Populus nigra, and Paliurus spina chiristi. Some of species such as Tulipa schrenkii was fed for pollen production. Results showed that this region in terms of water sources (86%), vegetation cover (63%), distance from road (33%), beekeeping activity period (24%) had high suitability for beekeeping. The average number of beehives per beekeeper was 318. Mean honey production was 19.6 kg per beehives in the Arasbaran region. Honey price varied from 110 to 600 thousand rials based on its quality. Average gross income of beekeepers was estimated about 835 million rials. The main problems of beekeepers were the presence of fake drugs in market (52%) and the lack of access for appropriate drugs for the treatment of diseases.

Quails have suitable properties such as rapid growth and high quality of meat. In this study, polymorphism of exon two of the gene encoding Growth Hormone (GH) and its association with growth traits in the Japanese quail were investigated. For this purpose, blood samples were taken from 150 Japanese quails and genomic DNA was extracted using Pronase method. Then, polymerase chain reaction (PCR) was executed to amplify a 162 bp fragment of GH gene. Single-strand conformation polymorphism (SSCP) method was used to determine the patterns of genetic samples. The results of SSCP showed four different genotype patterns in the exon two region of GH gene. The frequencies of genotype patterns were 11.64, 15.75, 37.67 and 34.94%. Association of body weight with genotype patterns was analyzed using the SAS software. Our results indicated that there is no significant difference between the genotype patterns and body weight in any period of rearing. However, for association of gender effect on body weight, there was a significant difference in the age of 60 days (maturity) (P≤0.05). Based on the multitude of genotypic patterns, the region in question in Japanese quail has a high diversity.

In this study, to estimate some population parameters and inbreeding rate in Lori Bakhtiari sheep flocks, the data set of 81 flocks of sheep were recorded from farmer flocks under current systems during 2015 to 2016. Questionnaire survey was used to collect data from last year information, recorded information, direct recording during visit the farm and interview with the smallholder farmer. The results showed that in 68% of the studied flocks, the male replacements were selected from the within flock, the selection criterion for all of the flocks was visual apparent characteristics and the type of mating was random. The average generation interval, the number of breeding ewes, the number of breeding rams, the proportion of ram to ewe, the duration of the ram stay in the flock were 3.30 years, 98.6, heads, 4.5 heads, 4.6%, 3.4 years, respectively, and 34.57% the flocks had at least one lamb with a visual genetic abnormality. Accordingly, the effective size and the rate of inbreeding, regardless of family size variance were 17.2 and 4.9%, respectively, and with family size variance estimated as 9.8 heads and 7.5%, respectively. The effect of city and type of breeding system were significant on most of the studied population parameters and inbreeding rate (P< 0.05). Therefore, the mean of effective size in farmer flocks was lower than minimum recommended for maintaining genetic diversity and implementation of the improvement breeding program, and this fact has caused an inbreeding rate of more than 5 to 7 times the permissible limit.

An experiment was conducted to evaluate the effect of different levels of black seed and two dietary protein levels on performance and blood parameters of broiler chickens. A total number of 336 un-sexed day-old Ross 308 broiler chickens were used in a 2×3 factorial arrangement with a completely randomized design consisted of 6 treatments (three levels of black seed (0, 1, 2 percent) in two protein levels (NRC recommended and 87% NRC, 1994)) with 4 replicates and 14 chicks in each replicate. All diets were iso-caloric and had the minimum nutrient requirements recommended by NRC (1994) except for protein. The results showed that using diets with NRC protein level rather to low protein diets resulted in a higher live body weight (P<0.05). Reducing dietary protein level led to reduced protein consumption and increased protein efficiency ratio (P<0.05). Reducing dietary protein level resulted in a significant decrease in carcass and thigh percentage (P<0.05). Serum albumin concentration decrease significantly when dietary protein reduced (P<0.05) Supplemented low protein diet with 1 and 2% black seed significantly improve live body weight, feed conversion ratio and protein efficiency ratio (P<0.05), as these values were similar to those birds were fed diets with sufficient quantity of protein. Supplemented low protein diet with black seed significantly improve breast, heart and gizzard (P<0.05) since their values were close to diets containing NRC recommended protein. These results demonstrated that supplementing black seed to low protein diet improve broilers growth performance.

The aim of this study was to investigate genome-wide Inbreeding and effective population size using the information obtained from 96 Zandi sheep breed using a density SNP panel (50K SNPChip). For this purpose, after quality control of SNP markers data, 40,879 SNPs were remained for computing inbreeding and effective population size. Effective number of breeders was estimated per each chromosome using NEESTIMATOR software based on heterozygote-excess method., and inbreeding coefficient was derived using four methods including, genomic relationship matrix (FGRM), excess of homozygosity (FHOM), correlation between uniting gametes (FUNI) using GCTA software and run of homozygosity (FROH) using PLINK software. Average expected and observed heterozygosity ranged 0.393 and 0.407 respectively. Average chromosome-wise effective number of breeders was equal to 69 and corresponding average confidence interval was between 40.0 and 93.26. The magnitude of inbreeding coefficient using FGRM, FHOM, and FUNI was similar (0.064) and it was estimated 0.053 using Run of homozygosity. Generally, the results indicated that although a considerable genetic variation exists in Zandi population in case study, however effective population has been decreased strongly in Zandi sheep breed during recent years and designing of appropriate programs is necessary to conserve remaining purebred animals of this indigenous sheep breed.

This research was conducted to investigate the feasibility of estimating the weight of broiler chicks using machine vision technology. 600 Ross broiler chicks were reared under standard conditions for a 42-day period. At selected intervals (7 days), 60 birds from a total of 600 chicks were randomly selected and weighed individually using the appropriate scale. At the same times, digital images were captured individually and in groups 2, 3 and 4 of birds. The digital images were initially preprocessed and the necessary changes were made on the photos and required features were extracted from images by designing an appropriate algorithm, and these features were used to design the neural network to estimate the body weight of chicks. The correlation coefficient between the extracted features of digital images including the Major axis length, Minor axis length, Bonding box, Convex Area, Filled area, Perimeter and Area of the image with live weight of the chicks were 0/92, 0/93, 0/53, 0/99, 0/99, 0/94, and 0/99 respectively (p <0.01). A Multilayer perceptron neural network, which was trained with back propagation learning algorithm, containing 22 neurons in the input layer, 20 neurons in the mid layer and one neuron in the output layer presented the highest accuracy(99%) to estimate the weight of broiler chicks at different ages. The results of this study showed that there is a possibility of using image processing and artificial neural network as an appropriate and efficient tool to estimate the weight of broiler chicks during the breeding period.

This experiment was conducted to evaluate the effect of lysophospholipid and vitamin C on performance, carcass characteristics and immune response of broiler chicks reared under thermonatural and high ambient . A total of 1680 mixed sexes broiler chicks (Cobb 500) in finishing rearing period (days 21-38 of age) allotted to two groups. In the first group, 480 chicks were subjected to four treatments with four replicates (n=30) and maintained in usual ambient temperature (24±1°C, thermonatural group: TN). In second group, the 1200 chicks were subjected to four treatments with 10 replicates (n=30), and exposed to high ambient temperature (34±1°C for 8 h daily, heat-stressed group: HS). Based on a 2 × 2 factorial arrangements in both groups, four experimental diets including LPLs (0 or 1000 mg/kg) and VC (0 or 500 mg/kg) were formulated and fed the chickens. In both groups, LPLs decreased body weight gain and increased FCR (P<0.05). In HS group, increased livability, antibody against bronchitis, relative weight of bursa and thymus were observed in chickens fed LPLs-supplemented diet (P<0.05) and increased relative weight of thymus and spleen were detected in chicks fed the VC-supplemented diet (P<0.05). In TN group, increased relative length of jejunum in birds fed LPLs-supplemented diet (P<0.05) and a significant interaction between LPLs and VC on response to phytohemagglutinin were detected. In conclusion, dietary supplemental LPLs and VC improved immune response of broiler chickens.

This study was conducted in order to determine the effects of adding molasses, barley grain and also, delay before ensiling on appearance characteristics, and nutritional value of canola silage. The data were analyzed using a completely randomized design with 2×4 factorial method. The experimental treatments were as followed: 1- silage without additive (control) and without delay before ensiling, 2- silage without additive with 48 hours delay before ensiling, 3- adding 5% molasses without delay before ensiling, 4- adding 5% molasses with 48 hours delay before ensiling, 5- adding 5% barley grain without delay before ensiling, 6- adding 5% barley grain with 48 hours delay before ensiling, 7- adding 2.5% molasses + 2.5% barley grain without delay before ensiling, and 8- adding 2.5% molasses + 2.5% barley grain with 48 hours delay before ensiling. Each of additives mixed with canola forage in 2 different times (0 and 48 h after harvest), and then, packed into plastic bucket containers, and were kept at 25°C for 60 days. According to the results, adding molasses increased water soluble carbohydrates, and decreased pH, neutral detergent fiber and acid detergent fiber (P<0.05). Delay before ensiling, improved appearance characteristics, and also, increased pH and crude protein of silage (P<0.05). In conclusion, molasses and barley grain with 48 hours delay before ensiling had a better performance, in terms of appearance characteristics, chemical composition and canola silage digestibility.

This experiment was conducted to determine the nutritional effects of dietary inclusion of a commercial local-produced probiotic (Bio-Poul®) on parameters of broiler growth curve. In this way, the fitting and prediction abilities of three models including the Gompertz, Logistic and Richards were compared. A total of 280 one day-old Ross chicks were used in a completely randomized design with four treatments and five replicates each (pens with 14 birds of both sexes male and female in equal numbers). Four dietary treatments containing 0, 100, 200, and 300 grams of Bio-Poul® probiotic per ton of feed were fed. To estimate the growth characteristics of birds, the weekly body weight of chickens from 0 to 42 days of age was recorded and fitted to the three growth models. Prediction abilities of the models in describing the growth of chickens were tested using goodness of fit indexes such as coefficient of determination (R2), root mean square error (RMSE), bias and a standard F test. Based on calculated indexes values, it was found that the Richards model had better prediction in compared with Gompertz and Logistic models with R2 value of 0.9998, RMSE of 9.16 g and bias of 0.52 g. In addition, the results of the pairwise comparison by F test showed that the Richards model was also more accurate in predicting growth of birds. In conclusion, the results showed that the diet containing 200 grams of Bio-Poul® probiotic may help to obtain optimum growth response and improve growth rate in broiler chickens.

Enhancing disease resistance in animal production can be achieved by genetic improvement programs. Candidate gene polymorphism is one of the potential approaches for search of association between SNP within this gene phenotype of animals, particularly in MAS for mastitis of large dairy cattle populations. Polymorphism of exon 9 of the BRCA1 gene was investigated by the PCR-RFLP method in 60 Iranian Holstein cattle. In this study, 3 different alleles were recognized. Polymerase chain reaction-restricted fragment length polymorphism method was used to amplify, digestion and electrophoresis for a 219 base pair of bovine BRCA1 gene. A polymorphism was revealed by G-A single nucleotide polymorphism in +46126 position of BRCA1 gene. Observe genotype frequencies for KK, KL, LL were 0.27, 0.43 and 0.30 respectively, and allele frequencies for observed K and L allele were 0.48 and 0.52 accordingly. For analysis of variance, normality test and transformation of raw data for SSC records was performed based on previous main reports and literature reviews. GLM and logistic regression methods was used for association study between genotype and collected phenotype. As a final message of the present report, KK genotype was showed significantly affect SCC data and has tendency for low SCC score than other two genotypes. The results of present study indicated BRCA1 gene as an effective candidate gene could be benefit for mastitis resistant in Marker Assisted Selection strategies in dairy cattle.

Control of diseases is one of the concerns in poultry industry worldwide. Despite the use of proper vaccines, antibiotics and sanitation in poultry farms, still disease outbreaks make irreparable economical loss. Another effective way of increasing the resistance of poultry to diseases is the genetic improvement of the immune system, which can reduce the current cost of taking vaccine and medicine. Considering the importance of IL-2 in the immune system, the present study was conducted to investigate the structure of IL-2 gene in Khorasan native chickens. To conduct this research, 20 DNA samples from Khorasan native chickens were used to amplify and sequence of 875-base pairs from the IL-2 gene. Comparison of the sequences obtained from the Khorasan native chickens with the sequence deposited in the NCBI showed mutations in the IL-2 gene, so that these mutations in the exon 1 region altered the amino acids. Exon mutations at 733, 738, 744 and 794 base pairs made to replace adenine bases instead of cytosine, thymine instead of adenine, adenine instead of cytosine, and thymine instead of cytosine. Identifying these mutations can allow them to be used as a genetic marker. To confirm this, we need to investigate the frequency of mutations and also examine their effect on IL-2 performance through proteomics experiments.

This experiment was carried out to investigate the Moghani ewe production performance improvement through reproductive management and nutrition methods during the non-breeding season in rangeland condition. For doing these projects, in one flock with 400 ewes, two groups were identified, that including group 1(estrus synchronization+hormone therapy+supplementary feeding) and group 2 or control group (without estrus synchronization+ hormone therapy+supplementary feeding). Supplementary feeding duration in pre mating for 4 weeks and 1.5 month in late gestation with concentrate were done. During the project, production, reproductive traits and economical evaluation was carried out in each two groups. For quantities data analysis of T-test methods and for qualitative traits were used of frequency table and Chi-square. The results showed that, parturition rate, lamping rate, twining rate, born lamb crop (BLC) and weaned lamb crop (WLC) in experimental group was more than control group (p<0.05). In terms of fecundity, there was significant statistical difference between two methods, so that 104.21 vs. 48.64 percent in experimental group compared with control group were observed (p<0.05). In conclusion, in non-breeding season, in Moghani ewe using of estrus synchronization+hormone therapy+supplementary feeding, have the highest economic interest compared to the control group.