Journal of Agricultural Sciences and Natural Resources
Year:2008 | Volume:15 | Issue:3|Papers Count:30

Iran is one of the main producers of caviar. The main objective of this study was to rank export goal markets of caviar and investigates Iran's relative advantages in exporting this commodity from 2000 though 2005. Data set were obtained from United Nation, World Bank, International Trade Center, and World Trade Organization database. For investigating Iran's relative advantages in caviar exporting, Revealed Comparative Advantage's index was applied. For ranking of export goal markets Riddle and Numerical Taxonomy processes were used. Indexes that were used in these two processes for each importer country include mean value of caviar import, the ratio of caviar import value to total world's caviar import value, the ratio of caviar import value to total import value of each country, import preference index, coefficient of variance of caviar import value, and increase in caviar import value's demand. The results of this study revealed that Iran had relative advantages in caviar exporting in all studied years. Riddle process suggest Japan, South Korea, Oman, France and Norway respectively and Numerical Taxonomy process suggest Sweden, Germany, South Korea, England and Cyprus as the best alternatives for caviar exporting.

Technical and Vocational Training organization plans and implements different training programs for the industry's growth and productivity, specially agricultural industry and a lot of trainees after training and acquiring the necessary technical and vocational skills enter the work cycle every year. This organization also provides and implements in-service training proportionate to industrial and organizational needs to improve workers, empowerment. The present study was performed to examine the attitude of the managers of agricultural sector's industries (employers) and the trainees of technical and vocational centers (trained persons) towards the effect of technical and vocational training on agricultural industry in Golestan province. The present research is descriptive which was performed by survey method and the measurement tool was questionnaire (employer's questionnaire and trainee's questionnaire). The research findings showed that there was a significant relationship between the completion time of the training course and the type of the trainee's attitude towards the effect of technical and vocational training while there was no significant relationship between the trainee's monthly income and the type of their attitude towards the effect of technical and vocational training. The results also show that there is no significant difference in the type of the employers and trainee's attitude towards the effect of technical and vocational training according to the town of their activity and dwelling place, but there is a significant difference in the type of the trainee's attitude towards the effect of technical and vocational training according to the training course.

Inheritance, transformation and neoformation are the three main origins of clay minerals. Factors such as topography, parent material, ground water table, climate and land use change may affect their relative quantity and distribution pattern. This study was carried out in south-west Golestan in three different ground water table depths and forest, dry farming and hydromorphic conditions. The main soil moisture and temperature regimes are xeric-thermic and udic-mesic and the parent material is loess. The results showed that illite, smectite and kaolinite minerals are the main minerals in all studied soils. In the forest land with good drainage, well-leaching and lower pH, chlorite has not been observed. In hydromorphic Soils with the near surface ground water and poor drainage, the amount of smectite minerals was maximum and its origin was mainly related to neoformation. In soil under dry farming and deep ground water, drainage is favorable and the leaching process have provided favorable condition for K+ release and transformation of illite into smectite. Decrease in amount of illite with depth is mainly due to its transformation to smectite and in soils with poor drainage and near surface ground water can be related to limitation of lessivage and physical weathering due to seasonal variation of temperature and moisture. Occurrence and stability of vermiculite in the forest land is due to high leaching, increasing Al activity and relatively low pH of soil. Kaolinite has the inheritance origin and there is no clear relation between its quantity, ground water table and land use. Land use and ground water table depths are the most effective factors in distribution pattern and the relative amount of smectite and illite minerals. The distribution of vermiculite however is mainly affected by climate.

Understanding the soil quality indices on different landscape position and use appropriates indices would result in a better land management in such areas. The main objective of the current study was to assess some indicators of soil quality in almond orchards in Saman region, Shahrekord. The experiment consisting of a split-plot design arranged in a randomized complete block with three replicates. Tree parallel transects (as block), each 10 meter away from each other were selected in two slope aspects (North and South as main-plots). Soil samples were taken from the top 30 cm in four slope positions from summit to toe slope position (as subplots) under Almond tree (canopy spaces) and in open spaces with an interval of 10 meters. Soil texture, bulk density, electrical conductivity and the concentrations of total organic carbon, total N, microbial respiration, alkaline and acid phosphates activities and N mineralization were measured. The results indicated that the lower slope positions including foot slope and toe slope had the highest amounts of clay, organic C, total N, EC, alkaline and acid phosphates activities, N mineralization and C mineralization rates. The amounts of total organic C and N mineralization rates reflect the differences between the two slope aspects. The highest amount of, clay and C mineralization observed in the toe slopes of north aspect. In addition, both aspects and sampling locations had significant interaction effects on all soil quality indicators. Therefore, most soil properties are depended largely on landscape position that could have a long-term influence on soil development and evolution. Among the measured soil properties, the amounts of organic carbon, microbial respiration and phosphates activity are more suitable indicators for assessing the effects of landscape position on soil quality in the studied area.

Priming is one of the seed enhancement methods that might be resulted in increased seed performance (germination and emergence) under stress conditions. The objective of this research was to evaluate effect of priming on seed germination under wide range of temperature in cotton. Treatments were combinations of seven temperatures (15 to 45oC by 5oC interval) and two seed treatments (control and primed seeds). Hydro priming method was used; seeds of cotton Siokra324 were moistened in water for 16 h at 25oC. Results indicated that priming affects seed germination components. Primed seeds had more uniform at all temperatures with less time to reach 10 and 90% of maximum germination. Priming affected germination response to temperature; primed seeds germinated at broader range of temperature. Optimal temperature, with lower base temperature and higher ceiling temperature. Optimal temperature was 38oC for control seeds, but was 35–45oC for primed seeds. It can be concluded that priming improves cotton seed germination under a wide range of temperatures.

In order to determine the most important yield component of two wheat (Triticum aestivum) cultivars (Zagros and Koohdasht), a RCBD experiment was conducted with five sowing dates (14 December, 20 Januery, 18February, 20 March, 16 April) with three replications. In this research, grain yield/plant was considered as a function of grain No/plant and mean single grain weight. While grain No/plant was considered as a function of three components (spike No/plant, Spikelet No/spike and fertile floret/spikelet). Our results based on onthogenic relationships and path analysis coefficients revealed that both cultivar and sowing dates can affect the most important yield component. Our results indicated that cultivars have different responses to sowing dates  and these differences were clear for some characteristics as the most important yield component , the most important component of grain No/plant, and compensatory effects of yield components, specially for mean grain weight and grain number. In this respect results indicated that for Koohdasht cultivar, grain No/plant is more important than mean grain weight to determine grain yield/ plant and fertile spikelet/spike was the most component which affected grain No/plant, while the effects of sowing dates on the most determinant component of grain yield/ plant was completely variable, but similar to Koohdasht cultivar, spikelet No/spike was the most important component that affected grain No/plant in Zagros cultivar.

In order to evaluate the effects of harvesting time on germination indices and early growth of seedling, seeds of four canola cultivars (Hyola308, Hyola401, Hyola420 and RGS003) were sown at Rice Research institute of Iran, Rasht in a split plot design in randomized complete block basis with 3 replications in 2005-2006 growing season. The seeds of four canola cultivars at four harvesting times (based on seed moisture content in one third of bottom siliques of inflorescence on main stem: 45%, 35%, 25%, 15% were obtained at grain maturity stage. The seeds were surface sterilized and tested for standard germination analysis. The experimental design was a factorial in a Completely Randomized basis with 3 replications. Germinated seeds were counted at fifth and seventh days and germination percentage, seedling length, seedling fresh weight, seedling dry weight, vigor index, germination index (GI), germination rate (GR), energy of germination (GE) and mean germination time (MGT) were measured. Results showed that there was significant difference between germination indices at different harvesting times. There was also significant difference 5 between germination indices in canola cultivars. Mean Germination Time was the maximum in first harvest and germination index, germination rate, energy of germination and vigor index had the highest values in the fourth harvest. Hyola401 cultivar had the most vigorous germination and seedling growth than the rest.

The effects of water logging on root and shoot growth of chickpea genotypes; including Flip 97-530 (Kabuli) and Rupali (Desi) were examined in Research Glasshouse at CSIRO, Perth, Western Australia (WA.) During 2005. Glass wall root growth boxes (0.1×0.24×1.0m) were used as experimental units. Data were analyzed based on Randomized Complete Block Design with three replications. Water loggings were induced when the first root reached to 50 cm. The water level was maintained on the surface for 12 days. After that, water was removed by draining the root growth boxes. Results shoed that leaf area and shoot biomass were significantly decreased by water logging, but differences between genotypes were not significant. Root biomass significantly decreased in water logging treatment. In water logging condition, more than 86% of root biomass belonged to 0-20 cm layer of soil surface and less than 14% belonged  to 20-40 cm, while in control condition, more than 85% of root biomass was located in 0-40 cm layer and less than 15% belonged to lower layers (deeper than 40 cm). Flip 97-530 had more root biomass than Rupali genotype in both control and water logging treatments. Nodules activities were stopped during water logging, but after that, dramatically increased in a way that, there were no significant in number and weight of nodules per plant on water logging and control treatment.

This experiment was conducted in Sadough Salinity Research Farm subordinating to National Salinity Research Center (NSRC) in two years during 2003 and 2004 in order to determinate of threshold values in cotton (Gossypium hirsutum L.) cultivars to salt tolerance. Treatments were saline water (main plots) in four levels: 2 (control), 6, 10 and 14 dS/m and subplots were cotton cultivars in three levels: Varamin, Bakhteghan and Siokra. Soil salinity (ECe) in root zone determined by soil sampling during of growth season, orderly and variation of relative yield (Yr) to ECe investigate with linear and sigmoidial models. Therefore, salinity threshold values for Varamin, Bakhteghan and Siokra cultivars obtained 4.1, 4.8 and 5.0 dS/m, upon linear model and in sigmoidial model C50 obtained for above varieties 12.05, 13.31 and 12.56 dS/m respectively. The effect of saline water treatments on yield was significant in %5 probability, so that, the highest yield produced in control treatment with 1834.0 kg.ha-1 and 6, 10 and 14dS/m treatments produced %9.5, %34.1 and % 58.9 less yield than control, respectively.

Kouhmian forest which is a part of western Hyrcanian vegetation is located at the northern slope of Alborz range Mountain in south-west of Azadshahr, Golestan province. The lowest and highest of its height are 250 and 1550 m.a.s.l. The floristic-physiognomic investigation which was performed by walked-field procedure at 2nd seasonal sequence show that flora of this region includes 113 plant species that belong to 101 genera and 60 families. The families of Rosaceae (10 species), Labiatae (6 species), Asteraceae (6 species) with Graminae, Solanaceae, Polygonaceae and Papilionaceae which are contained 4 species and Aspediacea with Ulmaceae which are contained 3 species were the most important families, that contained 39 percent of the total species. Phanerophytes (40%), Hemi cryptophytes (37%) and Cryptophytes (14%) were the most important structure groups of the local biological spectrum according to Raunkaiaer method, whereas according to Suzuki-Arakane method caespitose Hemi cryptophytes, broad- leaved decidous trees and Rhizom-Geophytes were the most important life forms. The chorological study according to Zohary method showed that plants of Euro-Siberian region and Hyrcanian province were common in study area whereas the least elements plant belonged to Plural region (Euro- Sib., Ir-Tur., Medit., Ir- An., and Pontic) with Euro- Sib., Ir- Tur. and Exin- Hyr. Phytogeographical regions. Moreover the damaged-factors were observed in the research area, that one mentioned as following: development of Viscum album (as semi-parasitic agent), high distribution of Labiatae family e.g. (Marrubium vulgar), some trees like Crataegus spp. and Mespilus germanica, also distribution of farmlands among forest areas. Therefore according to the current study and for conservation & preservation of this area, supplement and comprehensive study would be suggested.

This investigation was carried out to study of the effect of monensin on performance, blood metabolites and urine pH of Moghani finishing lambs. Forty male Moghani lambs with mean body weight of 30.89 1.44 kg and 5-6 months of age were used in a 84-day feeding trial. The trial was carried out using completely randomized design with 4 treatments. The applied treatments were:1) control (without monensin) 2) 15 mg monensin per kg of dry matter 3) 30 mg monensin per kg of dry matter and 4) 45 mg monensin per kg of dry matter. For measuring blood metabolites and urine pH, 3 lambs were randomly selected from each treatment and blood samples were collected. The results indicated that monensin increased average daily gain and final weight in lambs fed monensin as compared with control group (P<0.05). Average daily gain and final weight were highest in 30 mg monensin group (193.69 gr, 47.24 kg respectively) and lowest in control group (135.83 gr, 42.41 kg respectively). Feed consumption was significantly different between experimental treatments. Feed consumption was highest in 15, 30 mg monensin (1.281, 1.279 Kg respectively) and lowest in control and 45 mg monensin group (1.237, 1.214 kg respectively). Although monensin improved feed conversion ratio (FCR), effect was not significant (P>0.05). Monensin had significant effect on blood glucose and phosphorus but had no significant influence on urea, calcium and total protein. Monensin had no significant effect on urine pH (P>0.05). The results of economical evaluation of experimental rations indicated that variable benefit per head lamb was highest in 30 mg monensin (137144 Rials) and lowest in control group (57650 Rials). According to this trial, due to desirable effects of monensin on lamb performance, use of monensin is recommended.

The objectives of this study were to measure urea nitrogen levels in blood serum (SUN) of lactating cows in Gonbad-kavoos area and relationship between their concentrations with some nutritional and environmental factors. Blood samples were collected in three periods (late summer, late autumn and late winter) from cows of four dairy farms (herd 1, herd 2, herd 3 and herd 4). Samples were taken 2-3 hours after morning feeding. Total mean serum urea nitrogen for all cows was 15.13±0.13 mg/dl. Mean serum urea nitrogen concentrations were significantly higher in herd 2 than in other herds and in herd 3 and 4 than in herd 1(P<0.05), but there was no significant difference between herd 3 and 4 (P>0.05) (respectively 14.39±0.22, 16.11±0.31, 14.70±0.21 and 15.36±0.29 mg/dl for herds 1, 2, 3, and 4). A highly significant difference (P<0.05) observed between the levels of SUN in herds that use urea in their silages and those who not use urea in their silages (respectively 15.41±0.19 and 14.85±0.18). Also, concentrations of SUN were significantly higher in herds that had used of commercial concentrates (herds 2 and 4) than in herds that had mixed their concentrates in farm (herds 1 and 3) (p<0.05) (respectively 15.75±0.22 and 14.54±0.15 mg/dl). Based on this study, serum urea nitrogen concentrations in Gonbad dairy herds were in acceptable status.

This research work was conducted to investigate the effect of using honeybee royal jelly as a protein source in tris extender on survival and motility characteristics of ram spermatozoa. Three Dallagh rams semen samples were pooled and subjected to six treatments, tris extender plus 0, 1, 2, 3, 4 and 5 percent of royal jelly, in a randomized complete block design with sub-samples in an experimental unit. Results of experiment showed that effect of royal jelly treatment improved survival of ram spermatozoa significantly (P<0.01). At post freezing stage, percentages of live and motile spermatozoa were improved with an increase of royal jelly in tris extender from 0 to 4% (34 and 31.32 to 37.32 and 34.41). Effect of tris extender with four percentage of royal jelly and tris extender with five percentage of royal jelly on live and motility of spermatozoa (37.45 and 34.56) was not significant (P<0.01). Therefore, the addition of four percent of royal jelly in tris extender is recommended for dilution and freezing ram semen.

A model was designed according to NRC (2001) equations, which simulates growth of preruminant calves based on three different indexes (Energy, Apparently digestible protein and mean of them). Results showed that the best estimation of calves weight in different ages was based on energy index (RMSD=7.251). Also model estimations of calves weight were generally greater than observations, so there were positive MBE values with RMSD=11.549, 16.705 and 7.251 respectively for mean index, apparently digestible protein and energy. Daily weight gain estimation according to energy index was lower than observed data, so MBE value was negative (RMSD=0.250). About the other two indexes (Apparently digestible protein and mean index), results showed that model estimations were greater than observations with positive MBE values (RMSD=0.241 and 0.307 respectively). Model made an over estimation about dry matter intake with positive MBE value (RMSD=0.666). According to model estimation trends, this model is a start point for designing a complex model. With respect to correct determination of observations trend, it seems a suitable model.

Genetic diversity of three lines of Iranian Silkworm (Japanies Lines) was assessed, using the AFLP markers. Samples (30 Larvae at 3 rd day of 5th instars from each line) were collected from Silkworm Research Institute (Rasht-Pasikhan). Genomic DNA was extracted from sericigence glands using phenol- chloroform method. In this Study ten PstI–TaqI primers combinations were used from which that 199 AFLP Polymorphic markers were generated. The dendrogram was constructed using the UPGMA method showed two groups, where Lines 31 and 103 were located in one group and line 107 in the other group. Average genetic diversity for total population and Primers was 0.3692. The lowest genetic diversity (0.1088) was observed for Line 31 and minimum was (0.1484) for Line 103. The maximum and minimum unbiased genetic distance was observed between Lines 31 and 107, and between Lines 31 and 103, respectively. Maximum and Minimum Polymorphism was observed in Lines 103 and 31, respectively. Genetic diversity of three lines of Iranian Silkworm (Japanies Lines) was assessed, using the AFLP markers. Samples (30 Larvae at 3 rd day of 5th instars from each line) were collected from Silkworm Research Institute (Rasht-Pasikhan). Genomic DNA was extracted from sericigence glands using phenol- chloroform method. In this Study ten PstI–TaqI primers combinations were used from which that 199 AFLP Polymorphic markers were generated. The dendrogram was constructed using the UPGMA method showed two groups, where Lines 31 and 103 were located in one group and line 107 in the other group. Average genetic diversity for total population and Primers was 0.3692. The lowest genetic diversity (0.1088) was observed for Line 31 and minimum was (0.1484) for Line 103. The maximum and minimum unbiased genetic distance was observed between Lines 31 and 107, and between Lines 31 and 103, respectively. Maximum and Minimum Polymorphism was observed in Lines 103 and 31, respectively.

An experiment was conducted to compare the effect of using different levels of fatty acid and calcium salt of fatty acid (fat powder) on male broilers' performance. A completely randomized design with five treatments and five replications with 16 Ross 308 male chicks for each treatment were used in this experiment. Treatments consisted of control (without fatty acids and fat powder), 3 and 6 percent fatty acid or fat powder. The whole feeding period was devided into starter and grower periods. All diets had the same metabolizable energy and protein level and for other nutrients recommended NRC (1994) was used. The results showed that performance of the chicks in different treatments was significantly different (P<0.05), so that treatment with 6 percent fatty acid provided significantly higher weight gain compare to other treatments (P<0.05). Treatments with 3 and 6 percent fatty acid showed improved feed conversion compared to treatments with 3 and 6 percent fat powder (P<0.05). Adding different levels of fat powder or fatty acid had no significant effect on carcass percentage, thigh percent and liver plus gall bladder percent but using 6 percent fatty acid resulted in higher abdominal fat percent compared to other treatments except control (P<0.05).

In this study, records of 305-d and first lactation milk and fat yield of 102371 Holstein cows were used to estimate genetic parameters by DF-REML and univariate and bivariate animal model. These data were collected from 514 herds during 1991 to 2001 by Animal Breeding Center of Iran. Animals that with calving age out of 18-36 months and animals without any record were deleted. Sires from different countries were divided in 7 genetic groups and regions of Iran have been grouped in 5 climate regions based on extended De Martonne method. Heritability of milk and fat yield based on univariate model in different climate regions were ranged from 0.22 to 0.30 and 0.06 to 0.26, respectively. Mean of heritability based on bivariate model were ranged from 0.24 to 0.30 and 0.12 to 0.26, respectively. The difference of mean breeding values from the daughters of sires for each trait was significant (P<0.01). Given positive correlation between these traits, in most regions, the highest and lowest average breeding value were belonged to daughters of Newzland and Iranian sires, respectively.

This experiment was conducted to study the effect of feeding raw and treated bitter vetch using a completely randomized design with 10 treatment and 4 replicates on performance of broiler chicks. Four hundred and eighty day-old broiler chicks were placed in 40 experimental units (twenty in each unit). Treatments were included a corn-soybean based diet as control, raw bitter vetch, soaked in water for 72 h with exchanged of water every 12 h and dried (SD), soaked in water for 12 h, autoclaved (120ºС, 20 min) and dried (SAD) in three levels containing 5, 10 and 15% in starter (0-21d), 10, 15 and 20% in grower (21-42d) and 15, 20 and 30% in finisher (42-49d) periods. Feed intake, daily weight gain and feed efficiency ratio (FER) were not affected by feeding of bitter vetch during 0-21 d period. Chicks raised with diets include 20% SD, 15 and 20% raw bitter vetch in during 0-42d and 30% SAD, 30% SD, 20 and 30% raw bitter vetch during 0-49d periods had a lower feed intake than control group (P<0.05). Daily weight gain and body weight were significantly lower in all treatments in comparision to control group at 42 and 49 days of age (P<0.05). Feeding diets containing 20% SD, SAD and raw bitter vetch at 42 days and all bitter vetch treatments in total experimental period (0-49d) significantly increased FER (P<0.05). Carcass yield was not affected by diets include 15 and 20% SAD and also 15% raw bitter vetch. In all levels of SAD and 30% SD bitter vetch liver weight was higher in comparision to control diet (P<0.05). Pancreas weight was significantly higher in 30% SD bitter vetch in comparision with control diet (P<0.05). Moreover, treatments had no significant effects on relative percentage of abdominal fat at 49 days of age. the results showed if there is an economical explanation, we can include leveles of 5, 10 and 15% of SAD and raw bitter vetch in starter, grower and finisher diets of broiler chicks, respectively.

In order to investigate physical and mechanical properties of cement bonded particleboard manufactured from recycled rail road sleepers, this study has been conducted. In this study six treatments including effect of temperature (at two levels: 25oC and 60oC) and calcium chloride as additive (at 3 levels: 3%, 5% and 7%) on cement boards properties were studied. One-layer boards with density of 1 gr/cm3 and 15 mm thick were manufactured. Three boards were also manufactured as control boards using normal particles, cement and 7 percent chloride (based on dry weight of cement). Physical and mechanical properties of manufactured boards including modulus of rupture, modulus of elasticity, internal bond, water absorption, and thickness swelling were measured and compared with control boards. Collected data were analyzed. There were significant differences (with 95 percent confidence) among manufactured boards. Since manufactured boards at 25oC and using 7 percent calcium chloride had high mechanical properties and less water absorption and thickness swelling compared with those manufactured at 60oC using 3 percent calcium chloride, therefore their manufacturing conditions are recommendable for industrial application. 

The aim of this study was to evaluate sound (control sample) and decayed wood of Iranian beech (Fagus orientalis) with a NDT stress wave method. Sapwood samples, with dimensions of 9 by 19 by 200 mm were decayed in laboratory soil-bed tests, based on European pre-standard ENV-807. The decay was evaluated by measuring percentage of mass loss (W), static modulus of elasticity (MOEs) in three-points bending test and also bending dynamic modulus of elasticity (MOEd) and longitudinal dynamic modulus of elasticity (Ed,l) using a NDT stress wave method after 6, 12, 18 and 24 weeks of exposure. The results show that both static and dynamic MOE measurements provide a more sensitive insight into property changes from fungal degradation compared with mass loss percentages. In this regard MOEd is more reliable compared with MOEd,l. There was also a strong correlation (r2=0.97) between the MOEs and MOEd for both sound and decayed Iranian beech. Furthermore, acceptable correlation was found between MOEd and mass loss percentages (r2=0.77).

To find the most effective soil properties on canopy cover of range plants, three rangeland type were selected with same elevation and geographical aspect. These habitat types include shrubland, grass-shrubland and grassland. The soil properties, including calcium, magnesium, phosphors, potassium, lime, ammonium, nitrate, organic material, pH, EC, bulk density, moisture, and soil texture were measured. The plant cover in each site in the representative stand was measured. The CCA and PCA were used in this study to obtain environment gradients and the most effective elements on the plant cover. The results showed that from the grassland to shrubland, organic material, potassium and silts were decreased, while pH and sands were increased. The most effective elements were organic matter and moisture in grassland, the nitrate and clay in grass-shrubland, and lime and sand in shrubland.

Knowledge of salinity-evaporation relation may be of prime importance in numerous situations, e.g. water balance in reseervoirs and lakes, and designing evaporation ponds. Invoking such a relationship is the aim of the present paper. Seven treatments of drinking water (as control) and saline water with salinities of 41, 68, 81, 203, 407, and 610 dS/m were designed in Pardis of Ferdowsi University of Mashhad. Evaporation was measured from containers with a surface area of 650 cm2 during one month period (Apr. 21 to May 18, 2006). There was a climatology station just near the study area. A linear regression was stablished  between measured values of evaporations and salinity levels. On the average, evaporation decreases as salinity increases. However the coefficieny of vationss (0.29-0.33) were not correlated with salinity level. Measured evaporations were compared with those of Dalton and Penman equations. There was a better fit for Penman equation, as its GSDER is closer to one (1.5-3.9) and its ME is low (0.1-1.2) as is compared with Dalton equation (higher GSDER and ME).

The purpose of this study was to determine the chemical composition and digestibility of olive cake produced in Golestan province. Olive cake was air-dried to reduce its moisture from 60-65% to 10-15% for storage and then its chemical composition and digestibility was determined using castrated sheep. For this purposes, 3 male castrated Dalagh lambs on the average 42±0.5 kg weight were used. Chemical composition of olive cake included dry matter (per cent), crude energy (cal/gr), crude protein (per cent), crude fat (per cent) and crude fiber (per cent) were 35, 3922.18, 7.69, 15.55 and 29.2. In addition, chemical composition of air-dried olive cake included dry matter (per cent), crude energy (cal/gr), crude protein (per cent), crude fat (per cent) and crude fiber (per cent) were 88.75, 3753.39, 9.5, 10.1 and 36.3. Results of apparent digestibility showed that dry matter, crude protein, crude fat and crude fiber were 13.28, 26.10, 74.67 and 28.7 percent, respectively.

67873 first lactation records of Holstein cattle were used to compare the performance of imported bull in different climates of Iran for milk and fat traits. Data were collected by the Iranian Animal Breeding Center from 1995 to 2001. Heritability estimated using REML method and derivative – free algorithm for milk yield and fat yield ranged from 0.16 to 0.25 and 0.06 to 0.24, respectively. Genetic correlations among regions ranged from 0.76 to 0.99 for milk yield and 0.46 to 0.99 for fat yield, respectively. In conclusion, different genetic parameters, low correlation between some regions and reran king of bull indicated that genotype by environment interaction may be present.