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L. Mosharraf Boroujeni, J. Keramat,
Volume 4, Issue 4 (1-2001)
Abstract

Recent restrictions on the use of artificial food colours have prompted extensive research on natural pigments as suitable substitutes. The red beet Beta vulgaris L. has been found as a suitable source of natural red pigment since beet powder and concentrates can conveniently be used in food products. In this research, hot and cold extractions of randomly selected red beets were used after preparation and blanching. The extracts were filtered and passed through a column of Amberlite XAD-7 resins after adjusting the pH to 2.5. The adsorbed colour compounds were extracted from the resins by eluting the column with acidified alcohol. The solvent was removed by vacuum rotary evaporator and solid colour was obtained, using a freeze dryer.

Physicochemical properties of the solid colour were determined by measuring ash and sugar contents of the solid colour. Also, its purity and stability were investigated under different conditions.

The amount of ash and sugar were negligible. The highest stability was observed at a pH value of 5 under cold and dark storage conditions. The purity of the solid colour was determined by scanning in the range of visible wavelengths and preparative TLC. The result showed that purity of the colour as a hundred percent betacyanins. The yield of production was calculated as 2.7 g powder per kilogram of beet. The colour was used in producing ice cream and frozen sherbets, which showed to be a suitable replacement for artificial colour carmoisine. Also the production cost of the colour was as low as less than 0.1 percent of that of ice cream or frozen sherbets.


S. Saboory Halestani, S.h. Dokhani, G.h. Kabir, R. Shokrani,
Volume 4, Issue 4 (1-2001)
Abstract

Four cultivars of olive, Kalamata, Marri, Zard and Fishmi were obtained from Roodbar town and treated with two methods, natural and controlled fermentation with Lactobacillus plantarum as a starter culture at 25°C for 100 days. HPLC analysis experiments were conducted during the whole study period. A higher level (1.08% w/w) of total acidity was produced in Fishmi cultivar especially in the natural fermentation (0.8-1.1 g lactic acid/ml) than in other cultivars. Individual organic acids were determined by HPLC. Quantitative changes of organic acids in olives showed (P<0.0l) an increasing pattern of lactic and acetic acids during fermentation, but decreasing levels of malic and citric acids were revealed. The highest level of lactic acid (1.1% w/v) was observed in Zard cultivar and the type of fermentation had no effect on acid production. Malic and citric acids gradually disappeared during 50 days of fermentation period and this change was faster for citric acid during controlled fermentation. Malic acid did not follow this pattern.
S.h. Dokhani, L. Rabiei Motmaen,
Volume 5, Issue 1 (4-2001)
Abstract

Physicochemical characteristics of potato (Solanum tuberosum L.) are very important for storage and processing qualities. The amount of reducing sugars (glucose and fructose) and organic acids at harvest, during and after storage is the most important factor. In this study, three potato cultivars (Moran, Marfona and Agria) were collected, dry cleaned and graded into three sizes. They were analyzed for specific gravity and dry matter content. Potato tubers were stored at 4°C and about 85% R. H. for 15 weeks and then reconditioned at room temperature (25±l)°C for 4 weeks. During the storage period of tubers, sugars (sucrose, glucose and fructose) were analyzed on a weekly basis, but citric, D-malic and D-pyroglutamic were analyzed on a monthly basis by high performance liquid chromatography (HPLC). Data were analyzed statistically in a completely randomized design with sampling and Duncans multiple range test.

The total sugar and organic acid contents of tubers significantly increased during the 15 weeks of storage at 4°C and decreased after reconditioning at room temperature. The size of tubers did not affect the accumulation of total sugars. Dry matter content and specific gravity of Agria tubers were higher than those of both Moran and Marfona. Also accumulation of reducing sugars was lower in Agria than in Moran and Morfona initially and after the storage and reconditioning periods. Therefore, Agria must be suitable for processing into chips or dry powder.


A. Mirlohi, M.a. Hajabassi, S.j. Razavi, E. Ghanaati,
Volume 5, Issue 1 (4-2001)
Abstract

Soil loss due to erosion is a common problem in most parts of Iran. Reduced soil organic matter and lack of proper agricultural management have intensified the problem in recent years. Conservation tillage systems are becoming more widely used in corn production in other parts of the world because of soil losses due to wind and water erosion and energy inputs. Changes in tillage methods, however, create different environments for the germination, development and maturation of corn plants. Most corn hybrids have been selected and developed under conventional tillage systems but these hybrids mayor may not be well adapted to both systems. This study aims to evaluate the performance of five locally grown corn hybrids under zero and conventional tillage methods. The experiment was conducted for 2 years on a plot of land specified for this study. Experimental design was a split plot with randomized complete block arrangement and four replications.

Seedling and juvenile plant growth were not affected by tillage method and were similar for all hybrids. Plant dry matter was affected significantly by the cropping system and was lower in no-till method. Plant leaf area index and stem diameter reduced significantly in the no-till system. Reduction was greater in the second year of the experiment. Also grain yields were significantly different among years, tillage method and plant genotypes. Yield reduction was highest in the second year of the experiment under no-till cropping system. There was no interaction between tillage method and corn genotypes, indicating that, usually genotypes perform similarly with regard to grain yield under both tillage methods. The results suggest that corn production under no-till system in Isfahan is probably associated with yield reduction.


M. Shivazad, A. Seidavy,
Volume 5, Issue 1 (4-2001)
Abstract

An experiment was conducted in order to study the possibility of compensatory growth by changing dietary nutrients concentration in the female Arian broiler chicks using a completely randomized design by means of standard and diluted diets. By standard diet is meant diet recommended by Arian’s guide catalogue and by diluted diet is meant the diet used in Iran broiler farms. However, both diets contain the same nutrient/energy ratios. Chicks in the seven treatments received in their starter, grower and finisher stages standard and standard and standard, standard and diluted and diluted, diluted and standard and diluted, diluted and diluted and standard, diluted and standard and standard, diluted and diluted and diluted, standard and standard and diluted respectively. Furthermore each treatment contained three replicants and each replicant contained 30 chicks. This experiment was conducted in autumn using 630 female Arian broiler chicks for eight weeks.

 It was concluded that weight gain of chicks receiving standard diets during all stages of their growing period was the same as the chicks receiving diluted diet during their starter period and standard diets during grower and finisher periods. Feed consumption and feed conversion ratio of these treatments were statistically lower than other treatment groups. Furthermore, production index and percentage of mortality was better than other treatment groups. Likewise, viscera% and abdominal fat% remained significantly constant in all treatment groups. But the cost of feed per unit of live body weight was lower in the treatment receiving diluted diets in all three stages of their growing period.


A. Foroozandeh, A.h. Samie, G.r. Ghorbani,
Volume 5, Issue 1 (4-2001)
Abstract

The objectives of this study include the determination of the growth potential of Naeini lambs when fed with diets varying in energy and protein concentrations and also an investigation of the influence of level of energy and/or protein intake on carcass characteristics and composition. Ninety Naeini weather lambs (initial live weight 29.89 ± 2.9 kg) were used in a 92-day feeding experiment. Animals were blocked to each of nine dietary treatments. Diets contained either 2, 2.25 or 2.5 Mcal ME/Kg DM and 11.7, 13.2 or 14.7% CP diets were fed in a 3 × 3 factorial arrangement in randomized complete blocks.

Lambs fed with high energy diets consumed significantly more feed (P<0.05) than lambs given the medium (ME) or low energy (LE) diets. The average final body weight and daily weight gain for lambs fed with HE, ME and LE diets were 41.4, 38.3, 34.5 Kg and 162, 124, 74 g/d, respectively, which were significantly different (P<0.05). Feed conversion ratio in HE group was significantly lower (8.3) than ME (10.4) or LE (14.3) groups. Energetic efficiencies and protein efficiencies were better for HE than for ME and LE diets. Increasing dietary energy significantly (P<0.05) improved energy and protein efficiencies of the diets. Dressing percentage, lean meat and eye muscle depth were significantly (P<0.05) improved with increasing levels of energy in the diet, but also increased dissectible fat. No significant changes were observed in bone percentage and body ash due to any changes in dietary energy. As the protein level of rations increased, feed conversion ratio and carcass meat percentage increased, but carcass protein percentage decreased.


J. Torkamani,
Volume 5, Issue 2 (7-2001)
Abstract

The main objective of the present study is to analyze the effects of agricultural crop insurance on farmers’ technical efficiency and risk attitude. Required data came from questionnaires that were completed by the Institute for Planning and Agricultural Economics of the Ministry of Agriculture. Farmers’ technical efficiency and attitude toward risk were estimated using stochastic frontier production function and equally likely certainty equivalent method for both insured and non-insured groups. Results revealed that effects of agricultural insurance on farmers’ technical efficiency were significantly positive in the three study regions.

Results of estimating risk aversion coefficients of study farmers showed a positive effect of insurance on risk aversion coefficients. However, this effect was significant only in two of the climatic regions under study.


M. Afyuni, M.r. Mosaddeghi,
Volume 5, Issue 2 (7-2001)
Abstract

Tillage system effect, Conventional (CT) vs. No-Till (NT), on soil physical properties and Br transport was studied at two locations in North Carolina. The soil types were a Typic Paleudults at Coastal Plain (site 1) and a Typic Kanhapludults at Piedmont (site 2). Bulk density (BD), total porosity (TP), macroporosity (MP), and saturated hydraulic conductivity (Ks) .were measured in plant row (R), and trafficked (T) and untrafficked (N) interrows. A rainfall simulator was used to apply two early season rainfalls to 1 m2 plots where KBr suspension was surface applied for Br leaching study. The first simulated rainfall event (30 min) consisted of a low (1.27 cm h-1) or a high (5.08 cm h-1) rate applied, 24 h after Br application. One week later, the high rainfall rate was repeated on all plots.

 Soil samples were taken two days after applying first and second simulated rainfall (a week between them) and the end of season from different depths for measuring Br concentrations. Soil physical properties were affected by both tillage system and position.

Bulk density was higher in NT versus CT and in T position versus Rand N positions. Total porosity was lower in NT versus CT but MP was significantly higher in NT. Saturated hydraulic conductivity was about 90% lower at T position versus N and R positions. Coefficient of variation was quite large, making it difficult to obtain statistical differences between tillage systems. The surface l0-cm of soil contained the highest Br concentration for depth treatments with treatment differences occurring primarily in 0 to 25 cm depth. In first and second sampling dates, more Br leached under NT versus CT system. However, there was no significant difference between the two tillage systems in Br leaching at the end of the growing Season. In site 1, Br leached more due to the coarse texture and high Ks of the soil.


R. Honarnejad, M. Shoai-Deylami, M. Mesbah,
Volume 5, Issue 2 (7-2001)
Abstract

In order to analyze the genetics of tobacco cultivars’ resistance to blue mould (Peronospora tabacina A.) and to estimate the combining ability of the four resistant and susceptible tobacco cultivars (Bel 61-10, Bergerac C, Samsoun and Trumpf) received from CORESTA, these cultivars were crossed in 1997 in a half-diallel crossing system and in 1998 their parents and their progenies were sowed. Also to estimate gene effects controlling resistance and susceptibility of cultivars and to obtain F2, BC1 and BC2 generations, F1 generation was selfed and backcrossed with their parents. In 1999, the six generations (P1, P2, F1, F2, BC1 and BC2) from six families were evaluated in a complete block design with 3 replications and the resistance of genotypes against Peronospora tabacina were evaluated by the standard method of CORESTA and the parents with their F1 and F2 progenies were analyzed as a 4×4 half-diallel crossing system.

The ANOVA showed significant differences among genotypes concerning resistance to Peronospora tabacina and the generation means analysis indicated fit of families Bel 61-10 x Bergerac C and Bel 61-10 x Trumpf with additive-dominance model. The rest of the families showed non-allelic digenic interactions (epistasis) and were fit to 6-parameter model of Mather and Jinks. Because of moderate to high narrow sense heritability of resistance to Peronospora tabacina (from 34 to 85% for different families), the selection of resistant lines may be successful. The results showed significant GCA of parents for the resistance to Peronospora tabacina. So, the role of additive effects of genes concerning resistance to Peronospora tabacina was recognized and the estimated heritability (in the narrow sense) was from 72% to 75% for this trait.


H. Zahiraddini, S.r. Mirai Ashtiani, M. Shivazad, A. Nikkhah,
Volume 5, Issue 2 (7-2001)
Abstract

Two experiments were conducted to investigate the effect of dietary energy levels on the performance of Arian broiler chicks. Trial 1 was performed in summer and trial 2 in fall. Both experiments were accomplished in 5×2 factorial designs, involving 5 levels of dietary metabolizable energy and two sexes. Each of the 10 resulting treatments was replicated 4 and 3 times in trials 1 and 2, respectively. The metabolizable energy contents in diets number 1 to 5 were 2800, 2900, 3000, 3100 and 3200 Kcal/kg for starter (0-4 weeks) period and 2900, 3000, 3100, 3200 and 3300 Kcal/kg for grower (4-7 weeks) period, respectively. The ratios of energy to each nutrient were the same for all diets in each stage of the experiments.

In both experiments, body weight gain and feed conversion ratio improved significantly (P<0.01) when diets with higher levels of energy were consumed. Feed intake was affected (P<0.01) by the dietary energy content only in summer (trial 1) resulting from the reduced intake of chicks fed with the lowest energy level. Abdominal fat percentage was decreased (P<0.01) in chicks fed with the lowest energy diet in summer. In both experiments, the cost of the feed per unit of live body weight was reduced (P<0.01) in accordance with the reduction in diet density. As expected, body weight gain, feed conversion ratio, abdominal fat and cost of the feed per unit of live body weight for male chicks were significantly better than the same values for females (P<0.01).


A. Karimi, A. Samie, J. Pourreza,
Volume 5, Issue 2 (7-2001)
Abstract

This experiment was carried out to study the effects of supplemental Cu (0, 100 and 200 mg/kg) and vitamin C (0, 400 and 800 mg/kg) on cholesterol and other blood components in broiler chicks. A total of 360-day-old chicks in a completely randomized block design in a factorial arrangement were used. At 56 days of age one male and one female from each pen were selected, slaughtered and blood samples were collected at slaughtering time for further analysis. After separation of serum, cholesterol, fat components, Cu and vitamin C contents of serum were measured using the relevant methods.

 Copper, vitamin C, cholesterol, LDL and HDL of serum were significantly (P<0.05) affected by vitamin C and Cu supplementation. Hematocrit and mortality were not significantly affected.


S. Yarahmadi, S.r. Mirai Ashtiani, R. Ebadi, G.h. Tahmasebi,
Volume 5, Issue 2 (7-2001)
Abstract

In this study 130 honeybee colonies in 4 locations (Damavand, Tehran, Qum and Karaj-Savojbolagh) were sampled to determine the phenotypic correlations among 9 morphological and 3 production traits. The morphological traits were length (FL) and width (FB) of fore wing, cubital index (CI), length of hind leg (HL), length of probosics (LP), slender index (SI), length (WL) and width (WT) of wax mirror, distance between wax mirror (WD), index of wax mirror (IW) and corbicular area (CA). The production traits were honey yield (WH), pollen gathering (WP) and wax: production (WW). Data were subjected to analysis of variance, phenotypic correlations, stepwise regression and path coefficient analysis. Results of phenotypic correlations demonstrated that correlations between FL with FB (0.65), WL (0.361), WT (0.261), HL (0.555) and LP (0.257), WH with WP (0.300), WW with WH (0.560) and CA with WH (0.234) were significant (P≤0.01). FB with WH (r=0.204) was also significant but there was no significant correlation between CA and WP. Results of stepwise regression and path coefficient analysis showed that whereas morphological traits were settled as independent variables, much of the corresponding changes in production traits remain uninterpreted. In spite of the significant correlations among several morphological and production traits, body measurements alone are not suitable criteria to select colonies for high productions of honey, pollen and wax.
A. Hemmant, O. Taki,
Volume 5, Issue 2 (7-2001)
Abstract

Any mechanical force exerted on a potato tuber during the harvesting may result in mechanical damage. A few weeks prior to harvesting, haulm destruction could improve the rheological properties of the tuber and reduce its susceptibility to mechanical damage. The effects of elevator and oscillatory sieve diggers and haulm destruction on potato loss and mechanical damage were studied on a farmer field in Fereidan region of Isfahan. Two haulm management treatments (destruction and non-destruction) along with five potato diggers (elevator digger with a long main web and with agitator, elevator digger with primary and secondary webs and with agitator, elevator digger with a main web and with/without agitator, and reciprocating riddle digger) were laid out in a strip block design within a randomized complete block design with four replications. The main crop variety, namely Marfona, was planted in the field.

The results showed that the percentages of undigged and soil-covered tubers were significantly different among the potato diggers tested. These losses were due to the dices located to the sides of shares or gage wheels and wrong adjustments on the diggers. Comparing the performance of reciprocating riddle with elevator diggers, its sieving capacity was low and the severity of the mechanical damage and the numbers of tubers covered with soil were high. Haulm destruction was effective in reducing the peeler type damage (the less than 3 mm deep damage to flesh). Although the elevator digger with a main web (elevator chain) and without agitator had the least mechanical damage index, the differences among the elevator diggers tested were not significant (5%).


A. Aryavand, H. Fathpour,
Volume 5, Issue 2 (7-2001)
Abstract

Muteh wildlife refuge, with an area of about 220,000 ha, is situated at 95 km north of Isfahan. In this refuge, 511 species of vascular plants belonging to 284 genera and 59 families live along with 117 species of vertebrate animals belonging to 84 genera and 37 families.

 Rare plants of the area were classified into two categories of “endangered” and “vulnerable” according to IUCN, 1996 categories. The endangered species include Astragalus chaetopodus Bunge. Astragalus eriostomus Bornm. Astragalus indistinctus Podl. and Maassoumi Cousinia phyllocephala Bornm. and Gauba Cousinia rhaphiocephala Rech. f. Cousinia straussii Hausskn. and C. Winkl. Ferula kashanica Rech. f. Onobrychis psoraleifolia Boiss. var. Psoraleifolia and var. pleiophylla Bornm. The vulnerable species include Bunium caroides (Boiss.) Hausskn. ex Bornm. Dielsiocharis kotschyi (Boiss.) O. E. Schultz Dionysia caespitosa (Duby) Boiss. Dorema ammoniacum D. Don. Dorema aucheri Boiss. Dracocephalum kotschyi Boiss. Echinophora platyloba DC. Hymenocrater bituminosus Fisch. and C. A. Mey. Pimpinella deverroides (Boiss.) Boiss. Prangos cheilanthifolia Boiss. and Thymus daenensis Celak subsp. daenensis.

 The rare animal species of the region were classified into four categories: “critically endangered”, “endangered”, “vulnerable”, and “conservation-dependent species”. The critically endangered species are Felis silvestris Schreber F. caracal Schreber Jaculus blanfordi Murray (mammals) Gypaetus barbatus Falco pelegrinoides F. cherrug and F. peregrinus (birds). The endangered species include Vulpes cana Blanford Ochotona rufescens Gray (mammals) Falco naumanni F. columbarius Chlamydotis undulata (birds) and Varanus griseus (reptilian). The vulnerable species are Gazella subgutturosa Guldensteadt Canis lupus Linnaeus Meles meles Linnaeus Hyaena hyaena Linnaeus (mammals) and Aquila chrysaetos (bird). And, finally, the conservation-dependent species include Ovis orientalis Linnaeus Capra aegagrus Elxleben Panthera pardus Linnaeus (mammals) and Ammoperdix griseogularis (bird). The results from this survey were compared with the findings from the survey of some other protected areas in Iran.


M.j. Nazemosadat, A.r. Sepaskhah, S. Mohammady,
Volume 5, Issue 3 (10-2001)
Abstract

In the Islamic Republic of Iran, the occurrence of chilling and freezing stresses have frequently caused great damages to crops and horticultural products. In southern Fars Province (south Iran) the cultivation of citrus orchards is popular and the economic losses due to injury from chilling and freezing stresses may exceed billions of Rials annually. The drop of ambient air temperature (above zero) reduces the ordinary metabolism activity of plants and causes chilling stress. If the temperature drops below zero and remains there for a considerable time, intercellular freezing may occur. This process always kills the cells and provokes tissue injury. In the present study, the possibility of predicting daily minimum temperature using the dew point of a previous day measured at 18:30 was examined.

 It was found that the prediction of minimum temperature is possible if the dew points are modified on the basis of the air relative humidity. For the episodes that relative humidity varies from 45% to 55%, minimum temperature at day i+1 was found to be almost equal to the dew point on the previous day (day i). For the periods that relative humidity is above (below) this range, the minimum temperature on day i+1 was observed to be greater (lower) than the estimated dew point on day i.


H. Noushad, A. Ronaghi, N. Karimian,
Volume 5, Issue 3 (10-2001)
Abstract

Nitrogen fertilizer application for corn (Zea mays L.) based on available N of soil can decrease the need to N fertilizer and, consequently, reduce the risk of environmental pollution, especially that of groundwater and drinking water. The objectives of this study were i) determining soil N03-N critical level at 4 to 6 leaf stage, ii) to study soil nitrate distribution, iii) determining N rate required for maximum corn grain yield, iv) measuring soil residual nitrate nitrogen after harvesting, and v) using hand chlorophyll meter to evaluate N status of corn. The experiment was conducted under field conditions in Bajgah and Kooshkak research stations (Fars Province) in 1996 using a split plot randomized complete block design with four replications. Main plots were control, 60, 120, and 180 kg N ha-1 as urea. At 4 to 6 leaf stage each main plot was divided into two sub-plots and N was applied at 60 kg N ha-1 rate to one sub-plot and the other sub-plot was left as control.

 Results showed that critical soil N03-N level at 4 to 6 leaf stage in 0-30 cm depth for 90 percent relative yield in Bajgah was 12-14 and for Kooshkak was 8-10 mg kg-1 soil. The highest coefficient of determination between corn grain yield and soil N03-N in 0-30 cm depth for Bajgah was in furrow sample and for Kooshkak was in furrow and shoulder composite sample. In both sites, maximum corn grain yield, with 15.5% moisture content, was about 14 mg ha-1 that was obtained through the application of 120 kg N ha-1 as preplant plus 60 kg N ha-1 as sidedress which is about 1/2 of the application rate used by local farmers. The highest residual soil N03-N after harvesting was 24 and 18 and the lowest was 2.6 and 3 mg kg-1 soil for Bajgah and Kooshkak soils, respectively. When maximum corn grain yield was obtained, chlorophyll meter reading at the middle of leaf blade at dough stage, was 49 for both sites. It seems that N fertilizer application rate by local farmers is excessive.


A.h. Jalali, M.j. Bahrani,
Volume 5, Issue 3 (10-2001)
Abstract

The effect of N levels and planting densities on quantitative and qualitative characteristics of grain yield in grain sorghum (cv. Kimia) was studied in summer 1998 at Kushkak Agricultural Research Station, Shiraz University. The experiment was a spilt plot with 4 replications in which 4 levels of planting densities (7.7, 10, 15.4, 20 seeds m-2) were applied as main plots and 4 levels of N (0, 40, 80, 120 Kg N ha-1) as subplots.

 N application rates up to 120 kg N ha-1 increased grain yield (7240 kg ha-1), but due to increased planting density (5336 kg ha-1) the highest yield obtained from 15 seeds m-2. Interaction of N and planting density was also significant. Application of 80 kg N ha-1 and highest planting density produced 8702 kg ha-1 of grain. Different grain yields in different levels of N and planting densities were due to increased number of grains per basic branches of panicle and increased number of panicle per m-2. The trend of variation of crop growth rates (CGR) was similar to the trend of grain yield. Nitrogen application increased grain protein contents but planting density had no significant effect on grain protein. Phenolic compounds (tannins) decreased with increasing N application and with decreasing planting density. A negative correlation was observed between increased N content and increased phenolic compounds.


M. Zohravi, H. Nassiri Moghadam, F. Eftekhari Shahroodi, M. Danesh Mesgaran,
Volume 5, Issue 3 (10-2001)
Abstract

An experiment was carried out on 384 7d old commercial broiler chicks (Lohman) to study the effect of changes in source and level of dietary calcium and limestone particle size on the performance and tibial growth and calcification of broiler chicks. From day 1 to day 7, the chicks were fed with the commercial basal diet. On day 7, the chicks were weighted and randomly assigned to 64 groups, six chicks of similar body weight (82.2±5.4) per group. Each of the eight experimental diets was fed to eight groups of chicks for an experimental period of 49 days. Two calcium sources (oyster shell and limestone), two calcium levels (100% NRC and 85% NRC) and three particle sizes of limestone [ground (less than 0.15 mm), medium (0.6 to 1.18 mm) and coarse (1.18 to 4.75 mm)] were added to diets with the same energy based on a Randomized Complete Design, in which levels of calcium were nested into calcium sources. Particle sizes were nested into calcium sources and levels.

Limestone significantly increased phosphorus retention (in percentage of phosphorus ingestion) at the age of 21 and 56 days and increased tibial length, dry weight and ash weight at 56 days. Calcium level of 85% NRC significantly decreased feed intake and feed conversion, especially during the starter, and increased calcium retention (in percentage of calcium ingestion) at 21 and 42 days. Phosphorus retention and cortical thickness of tibia at 21 and 42 days, tibial dry weight, ash weight and ash percentage at 42 day, were significantly increased with calcium level of 100% NRC. Coarse and medium particle sizes of limestone as compared to ground particle size, significantly improved feed intake and feed conversion, especially during the starter. Medium particle size of limestone with calcium level of 85% NRC and coarse particle size of limestone with calcium level of 100% NRC, significantly improved tibia ossification characteristics and increased calcium and phosphorus retention. By using calcium level of 85% NRC, coarse and medium particle sizes of limestone compared to ground particle size, significantly diminished percentage of leg abnormalities.


A. Zare Shahneh, R. Mataji, M.j. Zamiri, M. Moradi Shar-E-Babak,
Volume 5, Issue 3 (10-2001)
Abstract

Effects of the β-adrenergic agonist metaproterenol were studied daily gain, carcass composition and feed consumption of Varamini female lambs were studied. Thirty lambs were randomly assigned to a randomized complete block design with three groups (treatments) and two blocks (live weight). The ration was similar for all groups (ME: 2.6 MCal/kg, CP: 14.9%) and lambs were fed ad libitum. Metaproterenol was injected subcutaneously at 0 (control), 7 (low dose) and 14 (high dose) µg kg-1 w75. Lambs were weighed at 20-day intervals.

Mean daily weight gain and feed conversion ratio improved significantly by metaproterenol (P<0.05), but feed intake was not affected. Hot carcass weight, carcass weight minus fat-tail, dressing percentage and longissimus muscle characteristics were different among the three groups (P<0.01). Physically separated fat from several depots and fat-tail weight significantly reduced in the metaproterenol groups. Carcass fat content decreased but carcass protein content increased in metaproterenol treated lambs.


R. Ebadi, R. Jafari, F. Majd, G.h. Tahmasbi, H. Zolphagharieh,
Volume 5, Issue 3 (10-2001)
Abstract

In this study, the control method of greater wax moth using male sterilization technique with gamma ray and chemical control methods were examined and compared. In order to determine the safe and effective dosage of gamma-ray to sterilize male pupae of the greater wax moth, an experiment was conducted in a complete randomized design with 5 treatments and 3 replicates with 50 male pupae in each replicate. Treatments included different levels of gamma-ray dosages with zero, 250, 300, 350 and 400 gray.

Release ratio of sterile to normal males was also studied in a similar experiment. Treatments included sterile-males, normal males and virgin females with the ratios of 1:1:1, 2:1:1, 3:1:1, 4:1:1 and 5:1:1. In this study, male pupae were irradiated with 350 grays of gamma-ray. The possible parthenogenetic reproduction of this pest was also studied. In order to compare the results from the male-sterile technique and the chemical control of this pest, another experiment was conducted in wax stores using 3 treatments with 3 replicates. Phostoxin was used as the most common chemical pesticide with a dosage of 1 tablet of 3 grams of 56% per 1 m3 space for the control of this pest.

The results showed that the best dosage to sterilize male pupae of the greater wax moth was 350 grays of gamma-ray. Also the best release ratio was four sterile male, one normal male for each normal female (4:1:1). Our results indicated that the females of the greater wax moth were not able to reproduce through parthenogenesis. There was no significant difference between the chemical and male-sterile methods for the control of this pest.



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