نشریه علوم دامی (پژوهش و سازندگی)
پیاپی 88 (پاییز 1389)

Hair samples، obtained from 56 dromedary camel (aged <1 to 12 years of age) in Khorasan province، were examined. Analysis of variance indicated a significant (P<0. 05) effect of sex on interrupted medullated، non medullated fibers، shoulder and hump staple length، and also on coefficient variation of mean down fiber diameter. There was significant different (P<0. 01) on interrupted medullated fibers and non medullated fibers of inner coat and shoulder، flank and hump staple length between young camel and other females of different age groups. The range of inner coat was 69. 4 and 96 percent that related to aged and adult groups in females respectively. The young and adult female camels have minimum and maximum of 15. 6 and 31. 16 μm mean down fiber diameter respectively.

In order to evaluate the fleece weight and the characteristics of wool fibers، 47 Arkhamerino×Ghezel (ARG) F1 ewes and 40 Arkhamerino×Moghani (ARM) F1 ewes were sampled in 15-month old. Greasy fleece weights (FW) were recorded immediately after shearing. Fiber diameter (FD)، variability of Fiber diameter (CVf)، staple length (SL)، kemp percentage (KP) and Modulated fibers percentage (MP) were assessed. FW، FD، CVf، SL، KP and MP in ARG were 1281. 92±33. 37gr، 27. 46±0. 53mic، 39. 09±1. 26 %، 15. 12±0. 49cm، 0. 67±0. 25 % and 5. 71±1. 17 % and in ARM were 1355. 56±62. 48gr، 26. 17±0. 9mic، 44. 88±2. 3 %، 13. 37±0. 60cm، 3. 21±0. 55 % and 11. 26±1. 71 %، respectively. The GLM procedure was used to analyze data for different genotypes and types of birth. The genotype had a significantly effect on CVf، SL، KP and MP (p<0. 05). ARM half-breeds had higher CVf، KP and MP but ARG half-breeds had higher SL. The type of birth had not any significant effect on fleece characteristics.

Double hump cameluse (Bactrian camelus) in Ardabil province are included as an adapted genetic resourse and great national welth that has been exposed to extinction because of the change of transporting system، illegal slautring and smuggles. In order to obtain the information about rearing double hump camels، all of members of their community (84 heads) in Moghan region were been investigated. At Moghan plain only sevene tribe are rearing Bactrian camelus. The type of this nomadic camels are meat-mohair، and rearing syestem is often semiambulant. Mean lengh of gestation period، percent calving in herd، period of estrous in seasonal mating and lengh mating were 384±12. 3 days، 99. 3±3. 2 percent، 9. 58±2. 7 days and 16. 84±4. 5 minutes، respectively. First mating with perganancy of femals was at three years old but first mating with fertilizer for males was in four years old. More of calving at seasonal winter and percent calving dead، abortion of fetus، twin birth and unfertilization were about zero. The mean birth wieght of kid camel dam and females was 40. 16±4. 6، 38. 25±4. 4 kg respectively. Mean length of milking 356±18. 3 days and the mean weaning kids at 350±32 day observed. The mean of pasturing/year was 246±39 month and grazing sesons are including spring، summer and autumn. The mean supplementry feeding/day for each of camels was 8. 54±1. 76 kg and often was included of alfalfa and spinouse plant for example alhagi camelurum، salsola، astaragalus and serseume. The mean of salt consumming/year at spring and summer was 63. 75±20. 85 kg for each members. Fattening camels is not current between camlus mans of Moghan region. The mean of total production of hair and mohair/ year was 8. 46±2. 56 kg.

This experiment was carried out in order to investigate the effect of heat stress and antioxidant (100 IU vitamin E and 50 mg/kg zinc) on birds receiving diet containing fish oil (unsaturated fatty acid) on performance and oxidative stability of thigh chicken meat. One hundred and sixty arbor acres female broilers were randomly assigned into 2x2 factorial treatment groups، temperature in 2 levels 300C and 200C and diet content %5 USFA with and without antioxidant (100ppm vitamin E and 50 mg/Kg. Zn) There were 4 replicates of 10 birds each. Meat samples stored at 40C and MDA produced at 0، 3، 6 days were measured by TBA method. The results showed that high environment decreases weight gain and increased feed efficiency (p<0. 05) but antioxidant addition to diet had no significant effect on these parameters. Results also demonstrated that heat stress increase USFA، mono unsaturated fatty acid (MUFA)، proportion unsaturated fatty acid to saturate fatty acid (USFA/SFA) and increased MDA produce in 0، 3 and 6 days (p<0. 05). Heat stress increased percentage fatty acid، gross energy and serum MDA Diet supplemented with antioxidant decreased USFA، omega-6 (n-6)، omega-3 (n-3)، polyunsaturated fatty acid (PUFA)، USFA/SFA and MDA produced at 0، 3 and 6 days. Also، USFA and gross energy of meat were higher in diet supplemented with antioxidant.

This experiment was conducted to evaluate the effects of changing time of starter، grower and finisher feeding periods on performance and carcasses quality of broilers in a completely randomized design. Six hundred and thirty Ross- 308 strain of broiler were randomly assigned to 7 dietary treatments with three replicate and thirty bird in each replicate and investigated for eight weeks in three different feeding periods. In control group feeding periods were feeding periods those recommended by NRC. Other 6 treatments included: S17G42F56، S25G38F56، S17G42F62، S25G42F52، S21G46F52، S21G38F56. At the end of experiment period the results showed that there were significantly difference between treatments in performance and carcasses quality (P<0. 05). There was significantly difference between treatments about average daily feed intake (P<0. 05). High amount of average daily feed intake (111. 55 g) was observed in 3 experimental group. Average daily weight gain was significantly difference between treatments (P<0. 05). High amount of average daily weight gain (57. 17 g) was observed in 7 experimental group. There was significantly difference between treatments about average final live weight (P<0. 05). High amount of live weight (3250 g) was observed in 7 experimental group. There were not any significantly difference among experimental groups in feed conversion and feed price (P>0. 05). However better feed conversion (1. 82 g: g) and low price of feed intake fir obtaining per kilogram of live weight (438 Toman/kg) were observed in 7 experimental group. Carcasses traits were significantly affected by different feeding periods (P<0. 05). There were significantly difference between treatments in breast meat percent (P<0. 05). High percent of breast meat (36. 36) was observed in 2 experimental group. There were significantly difference between treatments in thigh percent (P<0. 05). High amount of thigh percent (32. 48) was observed in 7 experimental group. The overall results of the present study indicate that in broiler with using the feeding periods like 7 experimental group، the improvement of performance and carcasses traits and reducing feed price is possible.

In order to compare two linear-linear (LLM) and linear-threshold (LTM) models in prediction of breeding values، two populations consisting of 6700 animals were simulated using of the Visual Basic programming language. In both populations the heritability’s for the first and second trait were assumed to be 0. 30 and 0. 10 respectively، but the genetic correlation between two traits was 0. 50 in population A and -0. 50 in population B. Selection of parents did on two trait selection index and mating of selected parents conducted randomly for 15 years. The second trait transformed into a categorical trait assigning 50 % of observed data in the first category، 34 % in the second، and 16 % in the third using the probit function. In the LLM breeding values were predicted under animal model and derivative free restricted maximum likelihood methodology and in the LTM predicted breeding values were obtained using a Bayesian method، implemented via Gibbs sampling procedure. Pearson correlation between two models for predicted breeding values in two populations (A and B) in continues trait (0. 93 and 0. 88) and in the threshold trait (0. 82 and 0. 62) was relatively high. Ranked correlation between predicted breeding values of two models was similar to Pearson correlation. Accuracy of selection in tow populations in the LLM was higher than LTM. The results indicated that the LLM was superior to LTM in prediction of breeding values and the LLM more accurately considers genetic correlation between traits than LTM.

Trigonella foenum-graecum (Fenugreek) and Foeniculum vulgare (Fennel)، in feed on growth performance traits including: Average daily feed intake (ADFI)، average daily gain (ADG) and feed conversion rate (FCR) and on antimicrobial activity of gut micro flora traits including: total number of bacteria in samples (TNB)، number of G- bacteria in samples (NGB)، number of Coli form bacteria in samples (NCFB) and recognition of Salmonella throughout the samples gathered from Ileum of chicks of different treatments. Trial containing 4 treatments (rations) and 3 replicates with 12 pens and 15 chickens per each pen (totally 180 chicks). Rations were balanced by NRC tables for different stages of growth from 1-21 and 21-42 days of old. The treatments were: 1. Control diet (without additives)، 2. Diet accompanied with 2 mentioned mixed powder plants (0. 5% of total diet)، 3. Diet with TF mixed powder plant and 4. Diet with FV mixed powder plant. All of additives through of diets were mixed to 0. 5% of total diet weights. According to the results the most ADFI (116. 19 and 116. 02gr/d) and ADG (53. 30 and 52. 98gr/d) related to treatment number 4 and 2 respectively. They were significantly different with other treatments (p<0. 05). Mentioned measures for treatments number 3 and 1 (control) were 103. 19، 112. 88 and 45. 26، 50. 39 gr/d respectively. FCR for treatment number 4، 2، 3 and 1 were 2. 19، 2. 18 2. 28 and 2. 24 respectively. The treatment group of 4 and 2 had a significant different with 3 or 1 (p<0. 05). Also culturing analysis of gut micro flora samples shown that the lowest total count of bacteria (TNB) belonged to number 2 and then 3 treatments with measure of 8. 83 for both of them (on basis of log10). The highest count belonged to control and then to number 4 treatments with counting of 10. 00 and 9. 50 respectively. The differences between two groups were significant (p<0. 05). By the same way، this algorithm repeated for counting of G- and Coli form bacteria، so the treatments 3 and 2 had the lowest (7. 33 and 7. 83 for G-، 6. 00 and 6. 50 for Coli form)، and the treatments 1 and 4 had the highest (both 9. 33 for G-، 9. 00 and 7. 17 for Coli form) counting of bacteria through the samples. The differences between this two groups for 2 type of bacteria were significant (p<0. 05). Results of culturing and isolating Salmonella for all the samples were negative.

In this study the data of birth weight (BW)، three months (3MW)، six months (6MW)، nine months (9MW) and yearling weights (YW) of Moghani sheep breed were used to estimate effects of environmental factors and genetic and phenotypic parameters. The data were collected from Jafar-Abad sheep breeding research station during twelve years period (1995 to 2006). Estimates of (co) variance components and genetic parameters were obtained using single and multiple trait models. The fixed effects were Year birth، month birth، sex of lamb، birth type and age of dam. The age of lamb at weighting was also used as covariate. Direct heritability estimates from five traits analyses were 0. 2±0. 03 for BW، 0. 18±0. 04 for 3MW، 0. 19±0. 04 for 6MW، 0. 29±0. 04 for 9MW and 0. 21±0. 04 for YW. Estimates of maternal heritability were 0. 18±0. 04 and 0. 18±0. 04 for BW and 3MW، respectively. Estimates of genetic correlations among growth traits were positive and ranged from 0. 48 to 0. 98.

The purpose of this study was to evaluate effect of gamma and electron beam irradiation on aflatoxin content of contaminated corn grain with fungi. Corn grain samples containing aflatoxin were exposure to gamma rays and electron beam، then content of aflatoxin was measured with HPLC apparatus. Experiment was conducted in a completely randomized design with five treatments (gamma or electron beam irradiation doses) and four replicates. The amount of aflatoxin decreased (p<0. 05) as irradiation doses increased. Gamma irradiation at doses of 10، 15، 20 and 25 kGy reduced the amount of aflatoxin by 14، 24، 49 and 69%، respectively، whereas، electron irradiation at the same doses reduced it by 11، 23، 46 and 66%، respectively. At doses less than 25 kGy، irradiation did not decontaminate aflatoxin completely; therefore higher irradiation doses are recommended. Based upon these results، gamma and electron beam irradiation were judged to be useful methods for reducing aflatoxin content of contaminated corn grain and decreasing it under permission level.

An experiment was conducted to evaluate the effects of inorganic and organic trace minerals sources (Zn، Cu، Mn، Fe، Se) on performance، egg quality and egg trace minerals concentrations of laying hens. Ninety 34-wk of age Lohmann LSL hens were used in completely randomized block design with 3 experimental groups and 3 replicates in each group with 10 hens in each replicate. The experimental diets were fed included: control (without inorganic and organic trace minerals); control with 0. 25% inorganic trace minerals and control with 0. 1% organic trace minerals. The hens performance، egg quality and egg trace minerals concentrations were evaluated in 28-d period. The results showed that the use of inorganic and organic trace minerals sources could not affected the production، egg quality and egg trace minerals concentrations (p>0. 05).