فصلنامه پژوهشهای تولیدات دامی
پیاپی 26 (زمستان 1398)

In order to reduce the risks of antibiotic use in poultry diets, the use of alternative additives such as probiotic and prebiotic compounds has attracted the attention of researchers. 128 quail chicks were randomly assigned to study the effects of different levels of synbiotic additive (KidiLact®) on performance parameters, immune response and histology of small intestine in Japanese quails. Quail chicks were distributed in completely randomize design with 4 experimental groups, and each experimental group consisted of 4 replicates and each replicate consisted of 8 birds. The experimental groups included either the first group or the control group without any supplement with the base ration, the second, third and fourth groups, the basal ration plus 1, 2 and 3 grams the synbiotic per liter of water, respectively for 30 days. According to the results of this study, different experimental groups had a significant effect on villi length, crypt depth, monocyte percentage, eosinophil percentage and Igγ percentage (p<0.05). The length of the villus and the intestinal crypt depth in the fourth experimental group were more than the control group, and daily weight gain parameters, the coefficient food conversion, intestinal weight, liver weight, duodenum, jejunum and ileum length, epithelial thickness and lymphocyte percentage were not significantly different between the experimental groups (p>0.05). Experimental groups also had significant effects on some immune response parameters in quail blood and monocyte percentage. Eosinophil and Igγ levels were higher in the experimental group than in the control group, but no significant difference were found in percentage of lymphocytes between the experimental groups was not difference. The results of this study showed that adding synbiotic has not a positive effect on the performance of avail chicks. However, the immune parameters and histologic indicators of the intestine have been positively impacted.

This study was conducted to evaluate the effects of diet containing inclusion of carvacrol, menthol and thymol at 400, 200 and 200 mg/kg, respectively, on performance, cell-mediated and humoral immune response using 96 broiler chicks in a completely randomized block design in 12 replicates of 2 birds each. Feed intake reduced in birds received diet containing menthol during days 14 to 42 of age (P<0.05). No changein weight gain and feed conversion ratio were observed in birds fed with supplemented diets compared with control birds (P>0.05). Mean antibody titer against infectious Bursal and Newcastle viruses was not differ for the chicks received diets supplemented with carvacrol, menthol and thymol at day 42 of age (P>0.05). Proportional weight of immune organs including the bursa of fabricius, spleen and thymus was not affected by the addition of monoterpens in diet at day 42 of age (P>0.05). The percentage of heterophils in blood was lower in birds grown on menthol-added diets than in control chicks (P<0.05). The experimental diets reduced the inflammation induced by phytohemagglutinin (PHA) injection at 6, 12, 24 and 48 hours after injection during days 32 to 35 of age (P <0.05). Based on dermal inflammation caused by PHA injection, carvacrol, menthol and thymol did not stimulate cellular immunity but showed significant anti-inflammatory activity.

This research was conducted to evaluate the nutritional value of vicia faba residues processed with some chemical compounds using in vitro and nylon bag techniques. Treatments included unprocessed vicia faba residues (control) and processed with water (2.5 lit/kg DM), calcium oxide (160 g/kg DM), hydrogen peroxide (57 ml/kg DM) and sodium hydroxide (50 g/kg DM). The chemical compositions of the samples were identified using the standard methods. Ruminal degradability trial was performed using the nylon bag technique. In vitro digestibility of samples was determined by the batch culture method. Processing was effective on the chemical composition of vicia faba residues. Except for water, the other treatments increased Ash and decreased organic matter (p=0.0001). Calcium oxide had the highest effect on the mentioned traits. Crude protein amount was decreased in all treatments (p=0.0001). The lowest amount was observed in calcium oxide and sodium hydroxide treatments. The amount of acid detergent fiber in calcium oxide and hydrogen peroxide treatments was higher than other treatments (p=0.0017). Except for calcium oxide and water, the other treatments increased effective rumen degradability of vicia faba residues at rumen outflow rates of 2, 5 and 8 percent/hour (p<0.0001). The hydrogen peroxide had the greatest effect on increase of effective rumen degradability. Sodium hydroxide treatment increased dry matter (p=0.0001) and organic matter (p= 0.0029) digestibility. Also, calcium oxide and hydrogen peroxide increased the efficiency of microbial yield (p=0.0016). Totally, the results of this research showed that the sodium hydroxide and hydrogen peroxide treatments had the greatest effect on improving the nutritional value of vicia faba residues.

This research was conducted to evaluate of chemical composition, aerobic stability, and microbial load of different genotypes of Vicia faba silage ( imported from Syria). 11 forage of Vicia faba of genotypes, including G-Faba-249, Histal, Barkat, G-Faba247, G-Faba100, G-Faba332, G-Faba256, G-Faba333, G-Faba331, G-Faba98, Luzde otono were used. The plant were harvested at late vegetable, three replicates per genotype, ensiled into 10 kg in plastic and opened after 60 days. Dry matter forage and silage, and pH, ammoniacal nitrogen and crude protein of the silage showed significant differences between genotypes of Vicia faba (P < 0.05). No significant differences were found among genotypes for lactic acid bacteria, but there were significant differences in total number of microorganisms and yeast among genotypes (P < 0.05). Genotype G-Faba-249 showed that had maximum time to reach peak temperature and the highest temperature. G-Faba-249 silage had the highest Filg,s point and physical appearance of was highest and evaluated as good. It was concluded that the forage of different Vicia faba genotypes at this reseach could be used as a quality silage for animal feeding.

The purpose of this study was to evaluate the effect of different levels of oil and soybean meal and Canola meal separately and mixed on productive performance, rumination and digestibility of nutrients in Holstein dairy cows. This research was carried out in a completely randomized design on 35 Holstein dairy cattle with 7 treatments and 5 cows with an average weight of 650 ± 40 kg. Treatments were: 1- control group (basal diet), 2- basal diet+ 4% soybean oil, 3- basal diet+ 10% soybean meal, 4- basal diet+ 4% Canola oil, 5- basal diet+ 10% Canola meal, 6- basal diet+ 4% soybean oil + 10% soybean meal, 7- basal diet+ 4% Canola oil + 10% Canola meal. The results of this study showed that with the use of soybean meal and soybean oil, the amount of milk produced per day increased milk production by 3.5% fat and milk production by 4% fat and the difference was significant (P <0.05) with other groups. There was a significant difference between the average duration of chewing, rumination and eating among different diets (P <0.05). The results showed that there were significant differences in the apparent digestibility coefficients of dry matter, fat and organic nutrients between different diets (P <0.05). The use of soybean oil and soybean meal improved yield of milk production.

The  low-consumption  elements such as selenium can be included in the diet from a variety of sources. The purpose of this study was to investigate the effects of incorporation of inorganic, organic and nano selenium in the diets of dairy calves on their performance, health, growth factor and some of their blood parameters. Forty-eight newborn Holstein calves were used in a completely randomized design over a 60-day period with four treatments (6 females and 6 males per treatment) as follows: 1) control diet without selenium, 2) mineralized selenium supplemented diet, 3) organic selenium supplemented diet, and 4) nano selenium supplemented diet. Except for control (1) other treatments had the same concentration of selenium (0.3 mg / kg diet). Body weight changes, growth parameters, fecal consistency, health scores, biochemical metabolites, liver enzymes activity, glutathione peroxidase, total antioxidant capacity, non-esterified fatty acid values, beta-hydroxybutyric acid and malondialdehyde were measured. The results showed that selenium sources were ineffective on feeding and DM intake before weaning. Supplementation with selenium did not affect the live weight of the calves. Selenium sources had do not affect on blood parameters, while total blood antioxidant capacity was higher in calves containing organic selenium compared to other treatments (0.506 mmol / L). Body length, chest circumference and body capacity were affected by different sources of selenium. Nano-selenium supplementation increased the height of calves in comparison with other treatments. The present results showed that the optimum source of selenium was organic selenium for dairy calves.

Ensiling alfalfa is difficult due to some restrictions such as low water soluble carbohydrate concentration and high buffering capacity. This study was conducted to document the effects of supplementation of alfalfa silage with fresh whey and bacterial additive on gas production, dry matter, organic matter and crude protein degradabilities by in vitro method. Experimental treatments included the levels of 0, 30, 60 and 90 g fresh whey per kg of fresh alfalfa were added to the alfalfa silage with and without bacterial additive (3 × 108 cfu per g fresh alfalfa). The gas production was measured at 2, 4, 6, 8, 12, 16, 24, 36, 48, 72, 96 and 120 h after incubation. The data were analyzed using a factorial 2 × 4 in a completely randomized design. After 120 h incubation, the highest amount of gas production was related to alfalfa treatment with 90 g of fresh whey and bacterial additive and the lowest was for alfalfa treated with bacterial additive (147.93 and 133.54 ml/g DM, p<0.05). Adding fresh whey with bacterial additive at 3 different levels at 2, 4 and 24 h incubation increased the dry matter degradability compared to control (p<0.05). Add fresh whey at three different levels of 30, 60 and 90 g fresh whey, increased the fraction (a) dry matter degradability compared to the control (p<0.05). After 24 hours of incubation, adding whey with bacterial additive increased the crude protein degradability compared to control (p<0.05). The results of this study showed that the addition of whey at different levels increased rapidly degradable, slowly degradable fractions and effective degradability of dry matter.

Poultry meat with a high share in the food consumption is one of the most basic products for supplying protein to households. Due to the high amount of pollutants in this part, the environmental impact of the production of this product is necessary. In the present study, the environmental impact of broiler chicken production in both industrial and traditional breeding methods were evaluated using Life cycle assessment method in Mazandaran province. The environmental impacts of producing one ton of poultry were evaluated by IMPCAT 2002 methods in the form of 15 midpoint environmental indicators and 4 endpoint environmental indicators. The results of industrial chicken breeding showed that inputs such as fatty acids, food (soybean meal, corn, and wheat) and energy (electricity, diesel and natural gas) have the highest contribution to creating different midpoint environmental indicators. At the same time evaluating environmental indicators of chicken production in the traditional method showed that the highest share in the most environmental indicators related to the use of rice bran. Also the results showed that for the production of a one ton of industrial broiler chicken, the human health indicators 0.0063 (DALY), ecosystem quality 14321.46 (PDF.m2.yr), climate change 9300.45 (kg CO2 eq), and resources 42072.93 (MJ primary) and for the production of one ton of broiler chicken in the traditional way (organic), human health indices 0.0262 (DALY), ecosystem quality 52324.33 (PDF.m2.yr), climate change 35329.45 (kg CO2 eq) and resources 224848.1 (MJ primary). The overall results obtained from weighted environmental indicators showed that the production of broiler chickens by the industrial method due to the short growth period of the chicks, had lower environmental effects than traditional production methods.

Since inflammation is considered as one of the major challenges in different parts of the livestock industry, this study was conducted to evaluate the inflammatory strategy of combination and simultaneous usage of beta-2 agonist and glucocorticoid drugs on some performance characteristics in laying hens at late production stage and some of qualitative characteristics. The research was conducted in a completely randomized design, during a period of about 4 weeks, using 112 laying hens of High Line W-36 strains (older than 90 weeks). Birds were randomly divided to seven treatments (including one level of beta-2 agonist drug, one level of glucocorticoid drug, three combined levels of these drugs, one beta-blocking treatment and control) with 4 replicates per treatment and 4 birds were put on each replicate. The results indicated that the laying percentage and feed intake increased in beta-agonist and beta-blocker treatments (P <0.05) and decreased significantly in glucocorticoid and combination treatments (P <0.05). Also, in beta-2 agonist treatment, body weight and egg weight were significantly increased (P <0.05). In contrast, these parameters significantly decreased (P <0.05) in glucocorticoid and combination treatments. However, shell thickness significantly increased (P <0.05) in some combination treatments. Therefore, it can be concluded that beta-agonist as a stimulant of inflammation (in some tissues such as the ovary) has a positive effect on the performance parameters, while egg qualitative parameters performed better in the glucocorticoid and combined treatments which act as anti-inflammatory stimulants in the body.

Identification of genetic characteristics is an important factor for preservation of species life. The aim of this study was to identify the genetic characteristics of the Adani goat populations based on the cytochrome b (Cyt b) gene and to detec its phylogenetic relationships with the domestic and wild goat species using NCBI database. Blood samples were taken from 12 Adani goat and subsequently DNA was extracted using Sinaclon kit. The target area (892 base pair) was proliferated by specific primers using polymerase chain reaction (PCR) method and then sequenced. By analyzing the sequences, 5 haplotypes were identified based on 12 polymorphic sites. All mutation sites were transition and nonsense. The haplotype and nucleotide diversity and the average of a different nucleotide based on Cyt b region were estimated 0.57, 0.002 and 2.273, respectively. These results indicated high genetic variation in Adani goat. Using the NJ phylogenetic test results indicated that the Adani goat was located in the C. hircus branch and C. Aegagrus was in closer to them in compare with C. ibex. The placement of Capra hircus's goats and Adani goats in a similar branch is rational because of the dispersion of various races of this species throughout the world.

In this study, production, population and economic parameters of 30 buffalo herds of Khuzestan province in two sale conditions during 2016-2017 were used to estimate the economic value for production, reproductive and survival traits. Economic value of the traits were estimated by one unit increase for each trait using the maximum profit trend. The average annual revenue, cost and profit per head of buffalo for milk and local cream condition were 60480817, 59270944 and 1209873 Rials, respectively, and for just milk sale condition were 59220881, 59270944, and -50062.7 Rials, respectively. In the milk and local cream sale condition, as a proper sale, the economic value of production traits including milk yield, fat percentage, fattening male calf weight and weaning weight were 16774, 178011, 16051 and -46070 Rials, respectively, the economic value of reproductive traits including conception rate, live birth rate, calving interval, buffalo heifer weight and age at first calving were 476142, 527296, 9504, -36668 and -76743 Rials, respectively, and the economic value of survival traits including survival rate of buffalo cow, survival rate of calf from birth to 4 months of age, survival rate of buffalo heifer from 4 months to parturition and longevity were 364946, 216406, 143588 and 72030 Rials, respectively, per head of buffalo in a year. According to the results, selection for increasing the average milk yield, fat percentage and fattening male calf weight would improve the economic condition of buffalo breeder. Considering the negative economic value of calving interval and the age at first calving, breeding in order to shorten them can increase the economic efficiency of the herd. Also, due to the superiority of milk and local cream sale condition compared to milk sale as well as taking into account that due to the lower milk production in buffalo raw milk selling was unprofitable, dairy products selling along with milk can be regarded to improve the economic efficiency.

Due to their roles in regulating embryonic growth and development  members of DNA Methyltransferases (DNMTs) family have been shown to play fundamental parts in  embryonic fertilization to postnatal life; through regulating the establishment and/or maintenance of specific epigenetic marks. The present study was conducted to identify potential reported mutations within the exon 33 of DNMT-1, introns 4 of DNMT-3a and introns 3 DNMT-3a genes and their relationship with birth weight in Iranian Holstein cows. A total of 60 blood samples from Holstein dairy cattle with records of weight from birth to adult age were randomly collected from industrial dairy cattle farm located in Kerman province. Genomic DNA samples was extracted using Phenol-Chloroform method and target sequence was amplified with PCR using specific primers. Polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) and silver nitrate staining methods was used for screening potential mutation in target sequences. According to results of this study, in all cases, no mutation in target sequence were identified as all samples had the same specific SSCP pattern with respect to their size. The lack of polymorphism may imply that these region may be attributable to a relative inefficiency of PCR-SSCP for mutation detection, small sample size, stochastic effects of genetic drift and/or conserved nature of these genes due to either natural or artificial selection. According to the results of this study, analyzed sequence may not be informative as molecular marker for birth weight in Holstein cattle.

The study of milk production and composition curves in buffalo provides key pieces of information about genetic potentials and management-related strategy to both breeders and farmers. The objective of this study was to identify of the non-genetic factors of parameters for fitted Wood function on milk fat content (MFC) and milk fat percentage (MFP) curve of Azari and Khuzestan buffalo. The data were collected from 15065 and 15225 from Khozatani buffalo and 9571 and 9721 lactation period of Azari buffalo on MFC and MFP were used for further analyses. For the first phase, the Wood function for each individual within the investigated population was fitted. Then, environmental factors affected MFC and MFP in both populations were assessed. In the last step, after the estimation of curve parameters, the phenotypic correlation for both populations was estimated. Results of the present study showed the MFP of Khuzestan breed was almost % 0.5 lower than Azari breed and faster reached to the lowest point within MFP curve shape. Furthermore, because of the higher milk production rate of Khuzestan breed, the MFC of this breed showed almost % 25 higher at the peak,  compared to the Azari buffalo. Also, due to higher observation of daily milk production in Khuzestan buffalo, this breed has good potential to produce more daily MFC and less MFP than Azari. Finally, the outputs of the report this research may be effective in help to improving nutritional the feeding formulation and genetics programs of Iranian buffaloes.

The purpose of this study was to compare the accuracy of genomic evaluation for Bayes A, Bayes B, Bayes C and Bayes L multi-step methods and SSBR-C and SSBR-A single-step methods in the different values of π for predicting genomic breeding values of the genotyped and non-genotyped animals. A genome with 40000 SNPs on the 20 chromosom was simulated with the same distance (100cM). The π values that maximized the prediction accuracies in BayesC were 0.980 and 0.995 for the normal and gamma distributions of QTL, respectively, and were also used in SSBR-C method. Genomic prediction accuracy in the SSBR-C (π = 0.99) method was higher than multi step methods from 0.02 to 0.09 for gamma distribution. Results showed that considering mixture distribution and use of phenotype, genotype and pedigree information simultaneously, the SSBR-C (π = 0.99) method had higher accuracy than other methods and is considered a better choice in this scenario. Moreover, both single and multi-step methods showed similar prediction accuracy when the genetic architecture appeared to approach the normal distribution. Furthermore, SSBR-C (π = 0) method appeared to be more reliable choice that was due to regressions of true breeding value on estimated breeding value close to one in normal distribution. Generally, GEBV accuracy decreased as the distance increased between validations and training set, which was more sensitive for non-genotyped individuals compared to genotyped individuals.

Efficiency is one of the most important factors in productivity growth, especially in agriculture. The purpose of this study was to measure the technical, allocative  and economic efficiency and to identify the factors affecting them in dairy cattle stations of Moghan agro-industry company. The data of this research were gathered in 2017 by documentary study, observation and interview. In this research, Deap 2.1 and Eviews 10 software were used for analyzing performance calculations and determining effective factors, respectively. In order to design a data envelopment analysis model, the main variables used in the research included the herd size per head, feed and concentrate in kilograms, manpower in terms of man-days, hygiene per day, milk production and manure production in kilograms and total revenues were determined. Efficiency calculations were carried out with the assumption of the daily operation of milk production stations in the form of firm performance and the results were obtained daily, monthly and annual. Tobit regression analysis and parents' statistics were used to determine the effective factors on the amount of efficacy. The results showed that the technical efficiency with constant returns was 0.844 and with the return on the variable of 0.962. The company's scale efficiency was 0.918, in which 16 days performance of the company was recorded with a slower return to scale and 349 days with incremental returns to scale. The technical efficiency value in the general condition was 0.901, the allocation efficiency was 0.845 and the economic efficiency was 0.761. In general, milk production efficiency was the highest in January and the lowest in April. Factors affecting the amount of technical efficiencies of feed and concentrate and health variables. The effect of feed and concentrate in livestock diets and the level of health has been negatively affected by technical efficiency. Effect of feed and concentrate variables on negative economic efficiency and positive health variable. In terms of the effectiveness of different efficiencies on the income of milk production, technical efficiency and allocation had a negative effect and economic efficiency had a positive effect.