فصلنامه پژوهشهای تولیدات دامی
پیاپی 33 (پاییز 1400)

This study was performed to compare the effect of diets containing ethanolic extract of Echinophora platyloba at two levels of 0.3% and 0.5% and Phosphoflavomycin growth-promoting antibiotic (0.04%) on performance, immune response, and blood biochemical characteristics of broilers using 160 male day-old chicks in a completely randomized design manner using 4 experimental groups, 4 replications and 10 chicks in each experimental unit. The results indicate that in the fourth week of production, there was a significant increase in body weight of the treatment receiving Echinophora platyloba extract (0.3%) compared to other experimental groups (P≤0.05). On day 14th, in both groups fed with Echinophora platyloba extract (0.3 and 0.5%), a significant increase in feed conversion ratio was found when compared to the control and growth promoter antibiotic treatments (p≤0.05). The treatment fed with 0.3% Echinophora platyloba extract increased the percentage of carcass and spleen significantly (p≤0.05) when compared with other dietary treatments. No significant changes are found due to both levels of Echinophora platyloba extract on immune response and blood biochemical parameters of broilers. In contrast, the group fed with antibiotic significantly reduced the blood levels of LDL and ALP, when compared with control and 0.3% Echinophora platyloba groups (p≤0.05). In general, the application of Echinophora platyloba extract (0.3%) led to a significant improvement in performance and some carcass traits percentage of broilers and could be recommended as a suitable alternative to antibiotic growth promoters.

In the present research, decrease of dietary nutrients concentration and duration of its using were investigated on performance of broiler chicken. A total of 375 one-day-old male broiler chickens were used in 5 treatments and 5 replicates per treatment of 15 birds per each from 1 to 39 d. In the present study, “normal” diet is referred to a diet based on recommended requirements of broiler chicken strain, and “diluted” diet is referred to a diet diluted 7% for energy and essential amino acids. Experimental diets (respectively, for starter, grower and finisher periods) in the treatments were: T1) normal, normal, normal (control); T2) diluted, diluted, diluted; T3) normal, diluted, normal; T4) diluted, diluted, normal; and T5) normal, normal, diluted. In the whole period (1 to 39 d of age), daily feed intake (p<0.05) and daily weight gain (p<0.01) of control were greater than other treatments. Feed conversion ratio did not show a significant difference among treatments. In the finisher period, mortality was greater in control than T2 and T3 (p<0.05); however, in the whole period, there was no significant difference among treatments. Breast weight was greater in control and T3 than T2, T4 and T5 (p<0.01). The T2 and T3 had the greater bone ash than control and T5 (p<0.05). In general, using the normal diet through the whole period showed the best growth performance, although this treatment revealed the increased mortality and decreased bone ash during finisher period.

The objective of the current research was to investigate the influence of different levels of dietary energy and stocking density on body weight and immune system response in Ross 308 broiler breeder hens. For this purpose, a completely randomized design with 9 treatments included three diet energy levels 2600, 2750 and 2900 ME/Kg and three levels of stocking density (4, 6.5 and 9 birds/m2 in rearing and 3.5, 5.5 and 7.5 birds/m2 in laying period), were used with factorial arrange (3×3) and 4 replicates The results showed that, with increasing dietary energy level, live weight of hens increased significantly from 21 weeks to the end of the experiment (P <0.05), on the other hand, high density from the beginning of the experiment until 31 weeks had no significant effect on live weight of hens, but in the last 10 weeks, higher density caused more weight gain (P<0.04). The percentage of lymphocytes, monocytes, heterophiles and the ratio of heterophiles to lymphocytes did not show a significant difference between the three energy levels. However, the percentage of heterophils, lymphocytes and the ratio of heterophils to lymphocytes were higher in the high-density treatment (P <0.05). There was also no significant difference between the treatments in the observed titers including infectious bursal disease (IBD), bronchitis (IBV), reovirus (REO), Newcastle (ND) and influenza (AI). The results showed that increasing stocking density can cause stress in the herd and if the herd stocking density increases, it is necessary to re-evaluate the energy requirement.

This experiment was conducted to evaluate the effects of different levels of Alhaji maurorum L. on egg production, egg traits and blood parameters of commercial laying hen’s performance. In this experiment 144 Hy- line (w36) laying hens were used from 44-48 weeks of age in 4 treatments, 4 replicates and 9 hens per each replicate in a completely randomized design. Experimental groups included: zero, 1, 2 and 3 percentage of Alhaji maurorum L. Results showed Different levels of Alhaji maurorum L. had significant effects on performance, and increased feed intake and production percentage (p<0.05).  Egg specific gravity, egg shell ratio and yolk index decreased with increasing Alhaji maurorum L. level in diets up to 3% (p<0.05).  Different levels of Alhaji maurorum L. did not have any significant effects on blood biochemical parameters of laying hens (P>0.05). Generally, the results showed that the use of 3% of Alhaji maurorum L. in the diets of laying hens increases the feed intake and egg production percentage, but has an adverse effect on feed conversion ratio.

In order to investigate the effect of different levels of hydrolyzed feather powder on performance and serum biochemical parameters of broiler chickens, an experiment was conducted in a completely randomized design with four treatments, six replications and 26 birds per replicate from 15 to 42 days of age. Experimental treatments included: diet without hydrolyzed feather powder (control), and diets containing one, two, and three percent of hydrolyzed feather powder. The results of this experiment showed that the use of hydrolyzed feather powder up to level of three percent had no significant effect on body weight, feed intake, feed conversion ratio, livability and production index compared to control group. The use of hydrolyzed powder in diet significantly reduced the cost of feed per kg of live body weight (P<0.01). Blood parameters such as albumin, globulin, total protein, cholesterol, high density lipoprotein (HDL)- cholesterol and triglycerides were not affected by hydrolyzed feather meal levels. Ileal protein digestibility of hydrolyzed feather powder was measured 75.17%. Totally, due to the lower feed cost per kg of obtained live body weight and the ability of hydrolyzed feather powder to provide part of dietary protein, the use of three percent hydrolyzed feather powder in broilers diet is recommended.

The effect of different levels of density of flaked corn on performance, blood and rumen parameters of 48 Holstein suckling calves with an average weight of 38.5 ± 1.20 kg was studied in 4 treatments and 12 replications for 70 days. Treatments included corn grain in the mashed form (control), flaked corn with a density of 300, flaked corn with a density of 350 and flaked corn with a density of 400 g / l. Calves were weaned at 56 days of age and daily intake of initial feed and body weight up to 70 days of age were measured. The effect of feeding experimental treatments on weight gain and dry matter intake of calves was not significant. The results of this study showed a significant effect of the experimental treatments on the concentration of ruminal volatile fatty acids and blood triglycerides (p<0.05). The density of 350 g / l of flaked corn (Treatment 3) had the highest concentration of triglycerides, propionic and butyric acid and treatment containing flaked corn with a density of 300 g (Treatment 2) per liter had the highest amount of acetic acid. The highest concentration of i-valeric acid (i-VA) belonged to the control treatment (corn grain in the mashed form). The effect of the sampling period on functional, blood, and skeletal growth parameters was significant among ruminal volatile fatty acids and valeric acid isomers (p<0.05). According to the results of this study, corn grain processing with a density of 350 g / l had a better response to most of the studied parameters than other densities and without having a negative impact on calf performance was able to improve some performance, blood and rumen parameters of calves.

To determine the effects of addition of the protected saturated and unsaturated fats on performance, blood and rumen parameters of Holstein suckling calves an experiment using 40 newborn calves (20 females and 20 males) with 5±2 days old and an average weight of 35±2 kg after colostrum administration was carried out in a completely randomized design with four treatments and 10 replicate for 70 days. Experimental groups included: 1) control diet, without fat supplementation, 2) diet with 2% calcium-unsaturated fatty acid supplementation, 3) diet with 2% calcium-unsaturated fatty acid supplementation, and 4) diet with an equal mixture 1% of both were complemented. In order to evaluate changes in body weight, chest circumference and height, the data were measured and recorded weekly at 10 a.m. To determine the blood parameters, blood samples were taken from the jugular vein on the 30th and 70th days experiment. The results of this study showed that the addition of unsaturated and unsaturated fat supplements did not have a significant effect on calves' performance so that weight gain, feed intake, feed efficiency and fecal index were not significantly different in experimental groups. Also, skeletal growth of calves was not affected by dietary fat supplementation. Dietary supplementation significantly affected the digestibility of the diet (p<0.05). The digestibility of dry matter, organic matter and neutral detergent fiber was higher in all experimental groups receiving fat supplement than the control group (p<0.05). The highest fat digestibility was in the experimental group containing unsaturated fatty acids. Fat supplementation had no significant effect on ruminal fluid and blood parameters of calves. Due to the uniformity of energy and crude protein in the experimental diets, it was expected that the most important factor in the possible improvement of calf performance was the positive effect of these supplements on the digestibility of the diet and the biological role of fatty acids, especially in health. The results of this study showed a positive effect of supplements on digestibility, but these changes may not be large enough to affect feed efficiency and weight gain in calves.

In order to evaluate the effects of Omega-3 and Omega-6 fatty acids on the growth performance of milk-fed Holstein calves in the cold season, forty newborn calves (41.8 kg of body weight, average age=4 days) in 65 days period were allocated to one of four diets and ten calves per group, in balanced randomized complete design as the repeated measurements over time. The experimental treatments as follows: (1) starter feed supplemented with no fat source (CON), (2) starter feed supplemented with 3% Ca-salts of soybean oil rich in n-6 FA, (3) starter feed supplemented with 3% Ca-salts of fish oil rich in n-3 FA, and (4) starter feed supplemented with an equal mixture of Ca-salts of soybean and fish oil (1.5% each, DM basis). Calf starter intake in OMEGA-3 was higher than others (p<0.01), whereas the control group significantly reduced starter intake. Average Daily Gain was higher in OMEGA-3 in the entire period (3-60 d) (p=0.0309). Feeding supplemental 3% fish oil improved feed efficiency compared to control and Ca-salts of soybean oil treatments (p<0.01). Calves in the OMEGA-3 group had higher body weight at weaning (p=0.0100). The Omega-3 group had better fecal scores and fewer days with diarrhea and control group had higher. Based on the results of this experiment, simultaneous consumption of Omega-3 fatty acids under cold stress can play an important role in improving calf health and guarantee optimal growth.

In this study, the possibility of replacing fodder beet silage in proportions of zero, 25, 50 and 75% based on dry matter in the concentrated part of fattening ration of Grey Shirazi male lambs (forage: concentrates in the ration 60:40 percent) were evaluated. Experiment carried out in a completely randomized design with 4 treatments and 10 replications. Silage chemical composition and performance of lambs were evaluated. At the end of the period, the all lambs were slaughtered and carcass and meat characteristics were evaluated. The chemical composition of silage including dry matter, ash, crude protein, ether extract, neutral detergent fiber and acid detergent fiber Were 25, 16, 12.7, 1, 41 and 30% of DM, respectively. The average (kg) of initial weight, final weight, average daily gain and feed efficiency were not significantly different in the treatments (p>0.05). The mean of dry matter intake in the treatments (25, 50, 75 percent) that consumed fodder beet silage (1160.0, 1147.3, 1091.9 gr/d) was significantly reduced in compare to control treatment (1298.8) (p<0.05). The mean of feed conversion ratio in treatment with 50% replacement of fodder beet silage (4.8) showed a significant decrease in compare to control treatment (5.7) (p<0.05), but treatments of 25 and 75% replacement of fodder beet silage with control treatment and also with treatment of 50% fodder beet silage were not significantly different (p>0.05). Carcass and meat characteristics were not significantly affected by fodder beet silage feeding. The results of this study showed that the use of fodder beet silage in feeding fattening lambs up to 75% substitution of the concentrate part of the ration is possible without reduction in yield.

Forty Holstein heifers with an average age of 12-16 months (363.4 ± 32.8 kg BW) were used in a 2×2 factorial design, in which 10 heifers were allocated to four stalls. The current experiment prolonged 100 days with 10 days for adaptation period and 90 days for sampling period. The rations in this experiment had the same forage/concentrate ratio and the only difference was in the amount of dietary energy density and feed bunk space. Treatments included: 1) Small feed bunk space (24 cm) with low level of energy, 2) Small feed bunk space (24 cm) with high level of energy, 3) Large feed bunk space (48 cm) with low level of energy and 4) Large feed bunk space (48 cm)  with high level of energy. The results showed that meal frequency was affected by diet energy density as mentioned parameter was higher for treatments with low energy density in comparison with high energy density. Also, feed bunk space had significant effect on heifer feeding behavior through motivating of competition for feeding. As, the meal frequency (#/day) was higher and meal size (kg/meal) was lower for small feed bunk space in comparision with the large feed bunk space. The results clearly showed that feed bunk space is the key factor to motivate competition behavior of feeding in heifres.

The purpose of this study was to investgate resveratrol nano-protected antioxidant on rooster sperm. In this study, resveratrol was used in the forms of nano-protected (liposome and NLC) and plain in the semen extender. Immediately after the semen collection and for primary evaluations, for eliminating of individual effects the semen collected from 15 roosterswere pooled and added to the extender. Extending was done at 37 °C at a dilution ratio of 1:20. Different concentarions of resveratrol (20, 40 or 60 μM) were added to the extender in three forms of plain, NLC, and liposome. After diluting the semen, gradual cooling was carried out for 3 h at 4 °C. After the cooling process, the kinetic parameters (CASA), membrane integrity (HOST), viability, lipid peroxidation (MDA), abnormal sperm, were evaluated. The results at 24 and 48 hours at a temperature of 4°C indicate that the use of 40 μM resveratrol, resveratrol loaded in the liposome, and resveratrol loaded in the NLC improved the motility, progressive sperm motility, viability, and membrane integrity compared to the control group. The results of this experiment indicated that 40 μM resveratrol, resveratrol loaded in liposome and resveratrol loaded in NLC improved most of the evaluated parameters.

Long-term storage of liquid sperm causes changes in the morphological structures and sperm function. This study was performed to determine the effect of different levels of coconut milk in ram sperm extender on sperm quality parameters after storage in cool conditions. Sperm were collected twice a week from three adult Lori rams using an artificial vagina. After collection and initial evaluation of the samples, the selected ejaculates were mixed and the mixed semen was divided into six equal parts and each part was diluted in a ratio of one to 20, with different diluents. Six extenders were prepared by adding different levels of coconut milk (5, 10, 15 and 20% (volume/volume) and egg yolk (15% (volume/volume)) to the Tris base extender. Diluted semen was stored at 5 ° C for 72 h. The samples at 0, 3, 6, 24, 48, and 72 h were evaluated for sperm motility parameters (computer analysis system) viability (Eosin nigrosin staining), morphology (Hancock), membrane integrity (HOST), lipid peroxidation rate, and sperm DNA fragmentation rate. The experiment was performed in a completely randomized design and the data analysis was performed using SAS statistical software. The results showed that extenders containing coconut milk in terms of some motility parameters including VSL, ALH, VAP, VCL were not significantly different from extender containing egg yolk (p≥0.05). But in terms of total and progressive sperm, Lin, STR, and BCF were significantly lower than extender containing egg yolk (p<0.05). Survival, cell membrane activity, and normal sperm percentage were similar in all treatments (p≥0.05). Also, the rate of lipid peroxidation and the percentage of sperm with damaged DNA were not affected by the type of extender. In general, the results of this study showed that the use of coconut milk in ram sperm extender to preserve sperm in cold conditions, could not maintain sperm motility parameters as much as the yolk and it was not a suitable substitute for yolk in ram sperm extender.

This study was designed to evaluate the effect of organic acid (Biotronic) and silver nanoparticles coated on zeolite on performance and humoral immune response of broiler chickens under heat stress conditions using a total of 375 one day-old broiler chicks (Cobb 500). Chicks were allocated to five treatments, five replicates and 15 chicks per each replicate using a completely randomized design. Treatments included: (1) control (2) 1% Uncoated zeolite, (3) zeolite-coated with 0.5% silver nanoparticles, (4) 1 g/kg organic acids and (5) zeolite-coated with 0.5% of silver nanoparticles and 1g/kg organic acids. Heat stress was exposed at 34˚ C in sixth week. Chicken’s performance indices were measured periodically. Blood samples were taken to determine antibody response, sheep red blood cells (SRBC) and heterophile to lymphocyte ratio at the end of the third, fourth, fifth and sixth weeks. The results of experiment indicated that diet containing Nano silver with organic acid decreased broiler body weight compared with the control and organic acids treatment at growth period (days 42-21 of breeding) (p<0.05). Also feed conversion ratio was significantly higher in the Nano silver coated on zeolite treatment than control treatment, zeolite and organic acids groups in the whole experimental periods (1-24 days) (p<0.05). However, the results of the experiment showed no significant differences between all treatments on immune system (p>0.05). In conclusion, the use of Nano silver and organic acid at the above levels had no effect on immune system, but the diet of silver nanoparticles increased the feed conversion ratio in chickens.

In order to investigate the effect of royal jelly on the reproductive characteristics of Mazandaran native breeder hens, a study was conducted in completely randomized design with four treatments (zero, 0.5, 1 and 1.5 mg Royal jelly /kg BW), three replications and ten hens in each replicate. There was no significant difference in hatching rate between royal jelly and control treatments (p<0.05). Triglyceride and VLDL concentrations were significantly higher in the 0.5 and 1 mg treatment compared to the 1.5 mg of royal jelly and control treatments (p<0.05). Body weight in the treatment of 1 mg of royal jelly showed a significant increase compared to the control treatment (p<0.05). The weight of collected eggs in the week after royal jelly injection, was significantly increased in the 1 mg treatment compared to the control and 0.5 mg treatments (p<0.05). Egg width increased in the 0.5 mg treatment compared to the control treatment in the first week of injection and also in the 1.5 mg treatment compared to the control and 0.5 mg royal jelly treatments in the second week of injection (p<0.05). Egg shape index significantly increased in the 0.5 mg treatment compared to the 1.5 mg of royal jelly and the control treatments (p<0.05). According to the results, royal jelly injection can affect the characteristics of the egg. For better results, it is necessary to consider higher levels of royal jelly as well as increase the duration of injection.

Growth curves are an approach to describe the growth over a specific period of time, so it would be useful to use nonlinear growth functions to measure and predict weight at different times of an animal's life and calculate production profitability. Growth curves actually summarize the relationship between age and weight into a limited number of interpretable parameters. The aim of this study was to determine the best nonlinear model describing the growth curve in Mazandaran native chickens. To achieve this goal, body weight data on different ages of native chickens (hatch, 8 weeks, 12 weeks and sexual maturity) for the first 21 generations collected at the Mazandaran Indigenous Breeding Center were used. Nonlinear models of Gompertz, logistics; Brody, Verhulst, Richards and VonBertalanffy were tested to describe the growth curve. Fitting of nonlinear models was performed using nonlinear least squares (NLIN) procedure of SAS software. To determine the most appropriate growth function and comparison between models, the coefficient of explanation (R2), corrected coefficient of explanation, Bayesian information criterion (BIC), Akaike information criterion (AIC) and root mean square error (RMSE) were used. Gompertz model with the lowest values for MSE, RMSE, AIC and BIC statistics was detected as the best model describing growth curve and Richards’s model as the most inappropriate model describing growth in Mazandaran native chicken. Correlation between parameters obtained using the best nonlinear model (Gompertz) showed that the correlation between parameter and b was positive (72%) and the correlation between and k was negative (86%). Also correlation between parameters b and k was negative (95%). The value of coefficient of explanation and adjusted coefficient of explanation for different functions varied between 0.92 to 0.93. In general, the results showed that the Gompertz model was the best function describing the growth curve in Mazandaran native chickens that could be used in herd management to predict the future weight of birds.

In this study, body weight records of 19171 American Simmental beef cattle including 8758 bull and 10413 cows from 2000 to 2016 were used to estimate genetic parameters and trend. We conducted genetic evaluation of data from 5199, 10926, 7362 and 5636 genotyped beef cattle of gene-based single nucleotide polymorphisms (SNPs) for birth weight (BW), weaning weight direct (WWD), yearling weight (YW) and post-weaning weight gain (PWG), respectively. Genetic parameters estimated using univariate and bivariate animal models and BLUPf90 software. Heritabilities were estimated for BW, WW, YW and PWG 0.38 ± 0.02, 0.24 ± 0.01, 0.35 ± 0.01 and 0.22 ± 0.02 using univariate analysis, respectively. Genetic correlation between BW and PWG was 0.31. The highest and the lowest genomic accuracy were estimated for WWD (0.68) and PWG (0.27), respectively. Genetic trends were estimated for BW, WW, YW and PWG 0.13, 0.28, 3.43 and 0.05, respectively. In addition, slight changes were observed in the genetic trend of all traits, especially weaning weight direct and yearling weight across years of study which indicates the existence of specific selection goals and criteria in each of these traits. In general, three large-effect closely linked QTLs identified on BTA6 at 37 Mb, on BTA7 at 90 Mb and on BTA14 at 22 Mb. Because correlations were favorable between body weight traits, breeding program should be based on the simultaneous selection of these traits through the selection index.

Growth and reproductive traits are well-known characteristics of living organisms because of their direct relationship with economic benefits. Genetic description of the growth curve and the correlation of its parameters with growth and reproductive traits can be useful in determining selection strategies. For this purpose, 2035 quail data, which were collected during the years 1398-1396 in the Agricultural Research and Training Center and Natural Resources of Khorasan Razavi, were used. To identify the fixed factors affecting the traits, the linear model of GLM procedure of SAS software was used and to estimate the parameters of the growth curve, the nonlinear regression model of Gampertz was used. Genetic components variance (co) of growth curve and reproduction traits was estimated using maximum likelihood multi-trait analysis by DMU software. Heritability of body weight at 35 days (BW35), asymptotic weight (a), maturity rate (k), age at inflection point (IPT), absolute growth rate (AGR), relative growth rate (RGR), number of eggs (EN) and fertility percentage (FR) were estimated respectively 0.222, 0.238, 0.416, 0.283, 168 to be 0.22, 0.222, 0.283 and 0.071. Growth curve parameters with AGR and RGR and BW35 days had high genetic correlations (0.434 - 0.924). The strongest correlation was obtained between IPT and RGR (0.924). Except for genetic correlations between EN and FR percentage with other traits, most of the genetic correlations were positive. Based on this results, management of environmental factors are effective in increasing growth and reproductive performance, and genetic selection for growth trait using growth curve parameters can improve the genetic potential of the animals.

In order to optimally use the inputs, the efficiency of economic units is of great importance. The purpose of this study is to investigate the technical efficiency and economic value of some traits of production, reproduction, survival and growth of Holstein cows in Pars agro-industry. For this purpose, required information including: manpower, cattle population, feed consumption and milk production quantities were collected from Pars Livestock Unit by documentary study, observation and face-to-face interview and their efficiency was calculated based on production and economic performance. The variables used in the research include herd size in terms of head, feed and concentrate in terms of weight, manpower in terms of men per day, health in terms of number of days per day, milk production and production of manure in terms of kilograms and incomes in Rials, which include Income from milk sales, Rial value of livestock manure produced, income from sales of voluntary and forced elimination of livestock, income from sales of bulls and heifers in dairy farms were examined. Deap 2.1 software was used for performance calculations. Optimal decision was calculated numerically by a iterative method using compecon toolbox in MATLAB program. Probability of pregnancy in the first, second, third and higher lactation periods based on data analysis and using logistic regression and GenMod procedure of SAS software Obtained, the results showed that the average of technical efficiency with constant efficiency compared to the scale was 0.83; the average efficiency with variable efficiency compared to the scale was 0.86 The scale efficiency of this company was estimated to be 0.96. The amount of technical efficiency in general was 0.83, allocation efficiency was 0.87 and economic efficiency was 0.72. This unit was efficient in March in terms of types of efficiency, which means that during this month, in addition to consuming a certain amount of product produced with a minimum of inputs, the minimum costs are also considered in the composition of inputs, so the unit in this month was technically, allocative, economically and economically efficient and has a constant return on scale. Also, the highest economic value in non-optimal conditions in survival, reproductive, productive and growth traits, and also for survival rate after weaning, first calving age, milk fat and body weight of adult animals was equal to 234297.30, -41835.16, 128664.12 and 454227.93 Rials, respectively. In optimal conditions, the highest economic value for survival, reproduction, production and growth traits was related to the set of traits of production lifespan, and the calving interval, milk fatproduction and daily weight gain before weaning were estimated at 4594.88,9084.67, 1582264.09 and -1464.87 Rials, respectively. The reason for the difference in economic values of traits in optimal conditions compared to non-optimal conditions is due to the application of optimal livestock replacement strategy, so that the farmer's policy in eliminating and replacing, affect herd profit.

The aim of this study was to qtl mapping of body weight traits from hatch to 45 days on chromosome one in Japanese quail. For this purpose, a crossbred population from a four-generation crossbreeding pattern was used. The four strains A and M Texas, Wild, Italian Speckled and Tuxedo Japanese quail were crossed in diallel-cross, creating the first generation. Then, from the crossbreed of first generation, a mapping population including second, third and fourth generations was created. Blood samples were collected for DNA extraction and amplification of microsatellite markers on the chromosome 1 of the subcutaneous veins in tubes containing 0.5% EDTA. Observations included body weight traits from birth to 45 days with an interval of 5 days. The effects of markers and components of variance were performed with three models of additive, dominance and additive-dominance with AI-REML procedure of GVCBLUP software. Based on the estimated effects of markers, the point with the highest value of F statistic was reported as the QTL location. The results of QTL analysis in the additive model for hatch weight traits, 5 and 30 days indicate the presence of QTLs affecting body weight traits at the end, QTLs of 10, 15, 20, 25, 40 and 45 day body weight traits in the middle and for body weight trait 35 days, they were at the beginning of chromosome one. In the dominance model, QTLs affecting body weight traits including hatch, 5, 10, 15, 35, 40 and 45 in the middle and for body weight traits 20, 25 and 30 at the end of chromosome one were identified. The percentage of additive and dominance genetic variance due to markers in different models ranged from 0.17 to 9.4% and 3.3 to 23.3% of the total phenotypic variance, respectively. Therefore, the results of this study confirm the existence of at least two distinct gene loci with additive effects and dominance affecting body weight traits on chromosome one in Japanese quail.

Meat is an important source of protein and energy, which contains large amounts of essential amino acids and fats along with vitamins and minerals. The livestock industry is one of the most important sources of pollutants due to its high consumption of energy and water, as well as the production of excrement. In the present study, the environmental impact of cattle beef production in three industrial, semi-industrial and traditional breeding methods were evaluated using Life cycle assessment method in Mazandaran province. The environmental impacts of producing one ton of cattle beef were evaluated by IMPCAT 2002+ methods in the form of 15 midpoint environmental indicators and 4 endpoint environmental indicators. The results showed that in the industrial and semi-industrial production method, direct pollutants from livestock farm and in the traditional production method, the use of concentrate has the highest impact on creating intermediate environmental indicators. In different production methods, human health in the range of 1.72 to 1.92 Pt, ecosystem quality in the range of 13.36 to 17.5 Pt, climate change in the range of 1.41 to 1.62 Pt and the resources in the range of 0.31 to 0.46 Pt were changed. Also the final environmental indicator showed that the highest and lowest final environmental indicator occurs in the industrial and traditional production methods at the rate of 21.58 and Pt 16.81 per ton of live weight.