نشریه علوم دامی (پژوهش و سازندگی)
پیاپی 82 (بهار 1388)

The effects of administration of three lactobacilli isolates on performance, carcass characteristics and some blood factors of broiler chickens were investigated. Total of 320 day old male chicks (Ross 308) were randomly distributed to 4 experimental groups of 4 replicates of 20 chicks. Control group did not receive any probiotic culture in drinking water. Groups lactobacillus sp.1, L. rhamnosus and L. sp.2 received one of the three lactobacilli culture in final concentration of 10.6 log cfu/ml of drinking water from 9 to 49 days of age. Administration of L. rhamnosus culture resulted the highest body weight gain on day of 49 in comparison to the other groups (p<0.05). Lactobacilli did not influence the feed intake, weight and length of internal organs and carcass characteristics of chicks and blood factors except of spleen weight, jejunum length and total carcass weight (p>0.05).

A total of 270 chukar partridges were used in this study to determine the effects of grower diet with differing crude protein (CP) and metabolisable energy (ME) levels on the body weight (BW), live weight gain (LWG), feed intake (FI), feed conversion ratio (FCR) and carcase characteristics of chukar partridge raised in captivity. Chukar partridges were fed on grower diets containing 3 level of CP (14, 15.5 and 17%) and 3 level of ME (2800, 3000 and 3200Kcal/kg) from 8 to 16 weeks of age. Nine grower diets were arranged in a 3×3 factorial design with 3 levels of CP and 3 levels of ME. Each treatment was replicated three times with each replicate consisting of 5 males and 5 females. There were no significant effects of ME and CP on BW and LWG at 16 weeks of age (p< 0.05). The FI and FCR for 8 to 16 weeks period were not affected by dietary CP level. But the daily mean FI and FCR decreased when the ME level of grower diet increased (p< 0.05), the lowest FI and FCR were in partridges fed on a diet containing 3200KcalME/kg. The carcase and breast weights of male partridges affected by dietary ME level (p< 0.05), the lowest carcase and breast weights of male partridges were in groups fed on a diet containing 3000KcalME/kg. Weights of all carcase components of the male partridges were significantly greater than those of the carcase components of the females. There were no significant interaction between CP and ME levels on BW, LWG, FI, FCR and carcase characteristics (p< 0.05). It is concluded that the grower diet for chukar partridge raised for meat production should contain at least 14%CP and 2800KcalME/kg.

In this study were used production, reproduction, management and economic parameters resulted from recording of 7 flocks with 1133 head of breeding ewe during annual cycle of production in village system. The profit equation were evaluated for two situations: 1) current situation, that there is not any pay for grazing in range, 2) In this situation, assumed for grazing in range pay as same as grazing in pasture of residual crop and hay farm. To calculate the economic value for traits, the level of trait included in profit equation was increased by 0.1 standard deviation, while all other traits were held at their mean value and change in profit was as the absolute economic value for trait. To calculate the relative economic values, the absolute economic value of each trait divided by the absolute economic value of weight of wool. Sensitivity analysis of relative economic values to price levels of inputs and outputs was carried out. In the current situation, live weight or carcass weight accounted for 95.04% of revenue and wool and manure the remaining 4.96% Feeding and management costs (variable costs) represented about 73.97% and 23.68% (97.65%) of total cost respectively. For the current situation, relative economic values were 33.09 for conception rate, 43.27 for litter size, -2.67 for mature ewe live weight, 1.0 for weight of wool, 30.55 and 35.64 for lamb survival at 3 and 6 month of age, 15.71 for 6-month live weight, 10.87 for dressing percentage, -7.57 for proportion of fat-tail to carcass, 0.59 for fat-tail weight and 25.03 for carcass weight without fat-tail at 6 month of age. The relative economic values of considered traits for situation 2 were slightly less than current situation. Litter size and conception rate were the most important traits in a breeding objective for ewe in village system. Lamb survival at 3 and 6 month of age and carcass weight without fat-tail were the most important traits in a breeding objective for lamb in village system. Sensitivity analysis of relative economic values to changes in prices of input and output indicated that change in cost of input (feed and management) by ± 20% changed relative economic values of traits by equal to less than %2.4, while, change in output (carcass weight without fat-tail) by ± 20% changed these values more than %20.

This study was carried out to determine effects of gamma irradiation on ruminal crude protein degradation of corn grain and its escaped protein type by using nylon bags and SDS-PAGE techniques. Duplicate nylon bags of untreated or irradiated corn grain at dose of 25, 50 and 75 kGy were suspended in the rumen of four non-lactating Holstein cows for 2, 4, 6, 8, 12, 16, 24 and 48 h. Intestinal crude protein digestibility was measured using mobile nylon bag technique. Degradation parameters and effective degradability of crude protein were calculated by fitting data to a non-linear equation. Means were separated using orthogonal contrast for detecting linear, quadratic and cubic relationships. Gamma irradiation decreased linearly (p<0.001) washout fraction, had cubic effect (p<0.01) on potentially degradable fraction, and decreased linearly (p<0.001) effective degradability of crude protein. Electrophoretic analyses of untreated corn grain revealed that two zein subunits remained in bags evenafter 48 h of incubation and the main part of escaped protein was zein subunits. At zero incubation time, large amount of albumin and globulin were disappeared, but in gamma irradiated corn grain, these subunits were remained in bags in the latest incubation period. In irradiated samples, most part of escaped protein was two subunits of zein and globulin fractions. Gamma irradiation increased intestinal digestibility of crude protein and its effect was linear. Based upon these results, gamma irradiation appeared to be effective in decreasing ruminal protein degradability and increasing intestinal protein digestibility.

This research was carried out to investigation of grazing effects on some soil chemical characteristics. For this purpose, Kojur region in western of Noshahr was selected. By field inspection, three different areas including (reference area, key area and critical area) were recognized. Then, information of soil samples were obtained from to horizon of soil profile (0-10cm, 10-30cm), in two times of before and after grazing season. Five soil samples were taken from each horizon from each area. Firstly, data were tested for normality of distribution. Analysis of variance was used to test the treatment effects. Duncan test was indicate to separate the means. Results show that carbon, total nitrogen and organic matter decreased with increasing of grazing intensity. Value of pH, C/N, K and P were higher in heavy grazing. This research showed, heavy grazing jeopardized the sustainability of the ecosystem by creating negative changes in soil chemical and vegetation characteristic.

This study was conducted to determine the effects of different levels of canola seed (0, 5, 10, 15, 20 and 25%) in diet of laying hens on performance and egg quality traits. One hundred and ninety two laying hens were used in a completely randomized design with 6 treatments, 4 replicates of 8 birds per replicate. Hens had free access to experimental diets for 12 weeks. Performance traits were recorded daily and egg quality traits were measured monthly.The results showed that substitution of canola seed up to 15% in the diet had not considerable negative effects on performance and egg quality traits; however, the best results were obtained by 10% replacement. Feed intake, egg production, egg mass output (53.43 vs. 49.97 grams) decreased significantly (p<0.05) and feed conversion ratio (1.83 vs. 1.94) increased significantly (p<0.05) by substitution of 20 and 25% canola seed. Egg weight and feed cost per kilogram egg mass were not affected significantly by experimental diets. Increasing levels of full fat canola seed had no significant effect on shell breaking strength, egg specific gravity, albumen height and haugh unit. Shell thickness and shell weight decreased significantly (p<0.05) in higher inclusion of full fat canola seed (20 and 25%). In this regard, the highest values (0.3 mm and 9.87%) were obtained by substitution of 10 and 5% canola seed, respectively. Increasing canola seed levels significantly increased (p<0.01) yolk color. In conclusion, the results indicated that canola seed can be used in diet of laying hens by 10% of ration.

This study was conducted to investigate nutritive value of ensiled pistachio epicarp, possibility of different levels replacement of ensiled pistachio epicarp with corn silage and its effects on growth rate and carcass composition of lambs. To investigate nutritive value, gas production experiment, dry matter and crude protein digestibility by nylon bag method and determination of digestibility by two-stage Tilley and Terry method were done. Four groups of ten male lambs (age 6 months and average weight 35.23±0.66 Kg), were fed for 90 days, iso-caloric, iso-nitrogenous diets, containing either no added ensiled pistachio epicarp (control) and added levels 8.7, 17.33 and 26 percentage ensiled pistachio epicarp in rations (based on dry matter). After 90 days feeding, the lambs were slaughtered. The results showed that feeding lambs with ensiled pistachio epicarp up to 8.7 percentage of total dry matter intake did not affect lambs performance, feed conversion, body composition and health of animals. Pistachio by-product or the residue of pistachio after peeling has potentially high nutritive value but its biological effects in ruminants have not been studied extensively. Iran is one the main pistachio producer in the world and majority of pistachio is being produced in Kerman province. There is about 298939 hectares of pistachio garden in Iran and annual dry pistachio production is 307036 tones. The by-product of pistachio is about 491257 ton annually. This by-product contains: %64.5 epicarp, %25 cluster, %10 leaf and %0.5 nut and shell. There are some problems with this by-product are including: 1- deterioration in less than 24 hours so it could not stored for long term. 2-Pistachio epicarp contains high level of tannins and other phenolic compounds, and there is little information about its effects in ruminants. 3- This by-product is potentially an environmental pollutant and cost effective for disposal. This project was conducted to study the nutritive value of dried and ensiled pistachio by-product and assess its effect on performance of fattening lambs.

In this study body weight traits at hatch, 14, 28, 42 and 49 days, age of sexual maturity, carcass yield and mean of daily weight gain were compared in three strains of Japanese quail. 51 male and 51 female of each strain were randomly selected from the base population, located in separate cages and collected their eggs in every day and for two weeks. Mean of hatch weight in wild, black and white strains was 7.2, 7.1 and 6.9 respectively and differences were not significant. Body weight in other ages was significantly affected by strain and sex(p<0.001). Difference between LSM of carcass yield in wild, black and white were not significant. Age of sexual maturity in females in wild strain was more than that the rest. Difference of Mean of weight gain in three strain were significant except ages of 1 to 14 and 42 to 49 days (p<0.05). The result of this study indicated that wild strain have highest performance.

In this study, fattening performance and carcass characteristics of native male kids in the Fars province were studied by using factorial with two factors in Completely Randomize Design. The first factor was ecotype (A) consist of Torky (A1), Darabi (A2) and Mamasani (A3). The second factor was energy level of diets (B) include low (B1), medium (B2) and high (B3) energy with 1.9, 2.1, and 2.3 Mcal of ME per kg of diet respectively. One hundred and seventeen head male kids at six months age were divided into nine treatments of 13 kids per each. Duration of fattening period was 100 days. At the end of fattening period, six kids (from each group) were slaughtered at random. Initial body weight for A1, A2, A3 treatments were 20.4, 20.39, 20.37 kg (p>0.05) and for B1, B2 and B3 treatments were 20.38, 20.37 and 20.4 kg respectively (p>0.05). Final body weight for A1, A2, A3 were 29.15, 29.94, 28.55 kg (p<0.05) and for B1, B2 and B3 were 28.19, 29.5 and 29.91 kg respectively (p<0.01). Average daily gains (ADG) for A1, A2, A3 were 88, 95, 81 g (p<0.05) and for B1, B2 and B3 were 76, 92 and 95 g respectively (p<0.01). Feed intake (FI) for A1, A2, A3, B1, B2 and B3 were 0.932, 0.872, 0.836; 0.909, 0.901, 0.860 kg/head/day and feed conversion ratio (FCR) were 10.59, 9.18, 10.32; 11.96, 9.79 and 9.05 respectively. FI and FCR between goat ecotypes were not different, but between diets were different. Dressing percentage for A1, A2, A3, B1, B2 and B3 were 43.9, 44.2, 43.8; 43.3, 43.7, 44.9, Lean percentage were 74.5, 71.1, 70.8; 71.9, 72.2, 72.3, fat depots percentage were 3.21, 4.33, 4.98; 3.77, 4.04, 4.72 and bone percentage were 20.7, 23.6, 23.3; 22.8, 22.75, 22.03 respectively and had not significant differences between ecotypes and diets. Internal fat depots percentage for A1, A2, A3 were 3.73, 3.97, 4.02 (p>0.05) and for B1, B2 and B3 were 3.03, 4 and 4.69 respectively (p<0.01). Interaction effects of A and B factors on fattening performance and carcass characteristics were not statistically different. In this trial high energy diet had better ADG and FCR, so use of this diet in fattening is sujedted. Due to result of this trial on growth rate of Fars native kids, it may be suitable genetic progress with selection.

Normal and abnormal presentation, position and posture of twin calving were studied at calving time of 2265 Holstein dairy cows. The objectives of this study were: 1) the survey of normal and abnormal presentation, position and posture of fetuses in twin births of Holstein dairy cows. 2) To evaluate of dystocia due to disposition of twins at calving time. The data were analyzed using Chi- square and Macnemar methods. There were 125 (5.51%) twin births out of 2265 calvings. Anterior longitudinal and posterior longitudinal presentation in both fetuses were: 71.2% and 2.4%, respectively. The rate of posterior longitudinal and anterior longitudinal for the first and the second fetuses were 10.4%. The rate of anterior longitudinal and posterior longitudinal in the first and the second fetuses were 16%. There was no malposition. The highest malposture rate (4.8 %) in anterior presentation was lateral head deviation whereas hip joint flexion (breech presentation) was the highest (4.4 %) malposture in posterior presentation. The rate of dystocia in the first and the second fetuses were: 25.6% and 32%, respectively. Twinning in Holstein dairy cows increases significantly the incidence of dystocia (p<0.05). There is a significant correlation between the presentation and posture of the first fetus in twin births (p<0.05).

In this study, we used seven microsatellite markers (GUJ0023, GUJ0083, GUJ0055, GUJ0099, GUJ0041, GUJ0059 and GUJ0052), that showed high level polymorphism for analyzing of genetic variation in four quail strain [Canadian Pharach (CP), Spanish Pharach (SP), English White (EW) and Manchurian Golden (MG)] from Meybod research station. Whole blood samples were collected from 150 individuals belonging to four strains. Total Genomic DNA was extracted by the GUSN-Silica Gel kit. The PCR reactions were successfully done with all primers. All of locus-strain combinations tested for Hardy-Weinberg equilibrium by chi-square and likelihood ratio. All locus-strain combinations deviated from Hardy-Weinberg equilibrium except GUJ0023 in Canadian Pharach and Spanish Pharach strain, GUJ0099 in Manchurian Golden strain and GUJ0052 in Canadian Pharach and Manchurian Golden strains (P<0.05). The effective number of alleles per locus varied from 2.8064 (GUJ0099) to 4.4662 (GUJ0023). The highest and the lowest PIC values belonged to GUJ0023 in Spanish Pharach (0.6964) and GUJ0083 in English White strains (0.4415) respectively. The expected heterozygosity varied between 0.7438 and 0.5450. The lowest and highest DS, Rogers, Wright and coancestry genetic distances were obtained between (CP) with (SP) and (EW), respectively. The phylogenies based on DA, DS, Rogers, Wright and coansectry distances by unweighted pair-group method using an arithmetic average (UPGMA) were showed CP, SP and MG are together at one cluster and EW at another. We can conclude that microsatellite markers could be a useful tool for screening of biodiversity in quail populations. We have described informative quail microsatellite markers that would form a useful resource base of DNA markers as part of our initiative to develop a genetic map for quail. Furthermore, these studied markers could be used as a tool in future phylogenetic studies aimed at improving our understanding of the relatedness of quail to chickens and guinea fowl. The trend in comparative mapping in poultry is taking several directions including the analysis of cDNA clones and radiation hybrid mapping, and our results would contribute to this collective effort.