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Eslami A.,Islamic Azad University at Rasht | Zahedi S.S.,Agriculture and Natural Resources Research Center
African Journal of Agricultural Research | Year: 2011

Using satellite imagery processing technique, we can separate planting poplar lands with a low cost, high speed and precision. The present study was conducted in northern Iran using Indian Remote Sensing (IRS) satellite data in July 2006 and ILWIS software to identify the cultivated surfaces of poplar. Field visitation recorded 548 ground control points by GPS in the way of features in various areas of Guilan Province. Ground control point map was overlaid on satellite color composite (sample sat) as training points map (pixels). In supervised classification, box classifier, maximum likelihood, minimum distance and minimum mahalanobis distance were used to determine user's accuracy, overall accuracy and kappa coefficient of each method, separately. Results indicate that spectrum reflex of poplar species is different from other vegetations and separable; but it has very close interference with conifer forest, natural forest, rice field and canebrake. By determining suitable training points, poplar cultivated surfaces could be identified. Among the classification methods, maximum likelihood with 91.48% of overall accuracy and 90.75% of kappa coefficient is the best method for separating planting poplar lands compared to the other methods. © 2011 Academic Journals.

Barazandeh A.,University of Jiroft | Moghbeli S.M.,University of Jiroft | Vatankhah M.,Agriculture and Natural Resources Research Center | Mohammadabadi M.,Shahid Bahonar University of Kerman
Tropical Animal Health and Production | Year: 2012

Data and pedigree information used in the present study were 3,022 records of kids obtained from the breeding station of Raini goat. The studied traits were birth weight (BW), weaning weight (WW), average daily gain from birth to weaning (ADG) and Kleiber ratio at weaning (KR). The model included the fixed effects of sex of kid, type of birth, age of dam, year of birth, month of birth, and age of kid (days) as covariate that had significant effects, and random effects direct additive genetic, maternal additive genetic, maternal permanent environmental effects and residual. (Co) variance components were estimated using univariate and multivariate analysis by WOMBAT software applying four animal models including and ignoring maternal effects. Likelihood ratio test used to determine the most appropriate models. Heritability h a 2 estimates for BW, WW, ADG, and KR according to suitable model were 0.12 ± 0.05, 0.08 ± 0.06, 0.10 ± 0.06, and 0.06 ± 0.05, respectively. Estimates of the proportion of maternal permanent environmental effect to phenotypic variance (c 2) were 0.17 ± 0.03, 0.07 ± 0.03, and 0.07 ± 0.03 for BW, WW, and ADG, respectively. Genetic correlations among traits were positive and ranged from 0.53 (BW-ADG) to 1.00 (WW-ADG, WW-KR, and ADG-KR). The maternal permanent environmental correlations between BW-WW, BW-ADG, and WW-ADG were 0.54, 0.48, and 0.99, respectively. Results indicated that maternal effects, especially maternal permanent environmental effects are an important source of variation in pre-weaning growth trait and ignoring those in the model redound incorrect genetic evaluation of kids. © 2011 Springer Science+Business Media B.V.

Karami M.,Agriculture and Natural Resources Research Center | Ponnampalam E.N.,Australian Department of Primary Industries and Fisheries | Hopkins D.L.,Australian Department of Primary Industries and Fisheries
Meat Science | Year: 2013

Twenty-four entire male Kacang kid goats were fed diets containing 3% canola (n = 12) or palm oil (n = 12) supplements for 16. weeks. The goats had an initial live weight of 14.2 ± 1.46. kg and were fed a mixed ration ad libitum (10.4. MJ/ME and 14% crude protein). There was no difference in feedlot performance due to diet. Inclusion of canola oil reduced (P<0.05) kidney fat weight and increased (P<0.05) linolenic acid (18:3n.3) concentration in the blood plasma, m. longissimus lumborum (LL), liver, and kidney. The palm oil diet increased (P<0.05) myristic (14:0) and palmitic (16:0) acid content in the blood, but this did not alter these fatty acids in the LL muscle. Lipid oxidative substances in the liver and LL from palm oil fed kids were higher (P<0.05) than those from canola supplemented kids. The incorporation of canola oil into the goats' diet increased muscle omega-3 fatty acid content, but lipid oxidation was lowered in the blood and muscle LL. © 2013.

Kadivar A.,Shahrekord University | Ahmadi M.R.,Shiraz University | Vatankhah M.,Agriculture and Natural Resources Research Center
Tropical Animal Health and Production | Year: 2014

This study was performed to investigate the effect of periparturient body condition score on the occurrence of clinical endometritis and postpartum resumption of ovarian activity in dairy cows. Eighty-seven lactating Holstein cows, fed with a total mixed ration diet, were included into the study. Body condition scoring (using a 5-point scale with quarterpoint divisions) was performed by the same investigator using the visual technique every 2 weeks, from 2 weeks before until 6 weeks after calving. Palpation of the reproductive tract and ultrasonographic assessment of ovaries for detection of corpus luteum using a rectal linear probe was also performed at 2, 4, and 6 weeks after calving. Cows with clinical endometritis had significantly lower body condition score (BCS) than normal cows at all weeks pre- and postcalving, and cows that did not ovulate until 45 days after calving had a significantly lower BCS pre- and postpartum. Cows that did not ovulate until 45 days after calving also lost more BCS from 2 weeks before to 4 weeks after calving. Besides, first ovulation after calving take occurred later in cows with clinical endometritis compared to normal cows (P <0.05). In conclusion, low BCS is a risk factor for postpartum endometritis and delayed cyclicity in dairy cows. BCS loss from dry-off to early lactation and occurrence of clinical endometritis can significantly affect postpartum ovarian activity. © Springer Science+Business Media Dordrecht 2013.

Khanchezar A.,Shiraz University | Izadpanah K.,Shiraz University | Salehi M.,Agriculture and Natural Resources Research Center
Journal of Phytopathology | Year: 2012

Spiroplasma citri was associated with a disease of safflower characterized by stunting, yellowing, phloem discoloration and local or general necrosis in the Fars province of Iran. It was identified by ELISA using a locally produced polyclonal antiserum, by PCR with specific primers and isolation in culture medium. The 16S rDNA restriction fragment length polymorphism patterns of safflower isolates were identical with those of the other S. citri isolates. A known isolate of S. citri from periwinkle induced stunting, yellowing, phloem discoloration and wilting in safflower seedlings when transmitted by dodder under greenhouse conditions. A primer pair designed on the basis of S. citri plasmid was more sensitive than those based on spiralin gene or 16S rDNA for the detection of S. citri. Based on the sequence of the spiralin gene, S. citri isolates from safflower as well as other Iranian isolates were variable and grouped into two genetic clusters with 91.9-92.9% identity between groups. This is the first report of association of S. citri with a safflower disease. © 2012 Blackwell Verlag GmbH.

Mohammadi H.,University of Tehran | Moradi Shahrebabak M.,University of Tehran | Moradi Sharebabak H.,University of Tehran | Vatankhah M.,Agriculture and Natural Resources Research Center
Czech Journal of Animal Science | Year: 2012

Genetic parameters for reproductive traits in Zandi sheep were estimated from data records of 5025 lambs from 178 sires and 1967 dams collected between the years 1993 and 2010 using ASReml statistical package. Genetic parameters were estimated for four basic and two composite traits. Year of lambing and age of ewe were used as fixed effects. Due to repeated record of ewe animal direct genetic effects and permanent environmental effects were considered random. The heritability estimates for conception rate, number of lambs born, number of lambs born alive, number of lambs alive at weaning, number of lambs born per ewe exposed, and number of lambs weaned per ewe exposed were low with linear model - 0.05, 0.14, 0.12, 0.09, 0.05, and 0.04 respectively while the estimates resulting from threshold analysis were 0.11, 0.19, 0.14, 0.16, 0.12, and 0.11, respectively. Estimates of heritabilities for animal genetic and permanent environmental effects were low mainly due to the typical strong influence of environmental factors on reproductive traits. Estimates of repeatabilities for animal permanent environmental effects were low to medium by linear analysis, and medium by threshold analysis. These estimates of genetic parameters may provide a basis for deriving selection indexes for reproductive traits.

Vatankhah M.,Agriculture and Natural Resources Research Center | Salehi S.A.,Jihad Agricultural Organization
Small Ruminant Research | Year: 2010

The data set used in this study consisted of 22,493 records of ewe body weight, measured a maximum of four times per year on 1935 ewes, collected from 1989 to 2007 inclusive from a Lori-Bakhtiari research flock at Shooli station in Shahrekord. Genetic and non-genetic parameters were estimated using restricted maximum likelihood and GLM procedure in multi-trait animal model. The model included the fixed effects age of ewe, stage of production and year of recording, and random effects direct additive genetic, permanent environmental and residual. The animal model was employed to identify the effect of ewe body weight (as classification and continuous variable) on ewes productivity traits. The age of ewe, stage and year of production had significant (p<0.01) effect on ewe body weight. The least squares means of ewe body weight ranged from 55.78 to 65.01kg, increasing with age of ewe, the maximum body weight observed in 5 years old group and then decreased in the older age groups. The lowest ewe weight was seen at mating. The maximum ewe weight observed after parturition and decreased after weaning and at shearing. The heritability estimates of ewe weight at different stages of production as various traits were high (0.40-0.49). The estimates of genetic correlation between ewe weights at different stages of production were high and ranged from 0.89 to 0.99. Ewe body weight at mating affected all traits related to ewe's productivity significantly (p<0.05 or 0.01). There was a rising pattern in conception and lambing rate as weight of ewe increased up to overall mean plus 5kg (56.59-61.58kg) and a decline thereafter. The least squares means of number of lambs born and weaned, total litter weight (kg) at birth and weaning per ewe exposed increased with increasing ewe weight at mating. The total litter weight (g) at birth and weaning per kg body weight of ewe exposed decreased with increasing ewe weight at mating. The least squares means of total litter weight (g) at birth and weaning per kg metabolic body weight of ewe (BWT0.75) exposed increased with ewe weight up to overall mean plus 5kg and then declined. Thus, the highest productivity was for ewes ranging in weight from mean plus and minus 5kg at mating in Lori-Bakhtiari ewes (56.58±5kg). © 2010 Elsevier B.V.

Vatankhah M.,Agriculture and Natural Resources Research Center
Journal of Agricultural Science and Technology | Year: 2013

The data set employed in this study was comprised of a number of 6,800 records of lamb's longevity and their survival rate, collected from 1989 through 2009, from the Lori-Bakhtiari experimental flock at the Shooli Station in Shahrekord, Iran. The data were analyzed using linear models and proportional hazard models with Weibull function. These models included fixed factors and direct additive genetic, maternal additive genetic, maternal common environmental and residual random effects. Genetic parameters were estimated using Restricted Maximum Likelihood (REML) procedure fitting a sire model as well as animal models including different combinations of direct and maternal effects. Estimates of direct heritabilities of longevity and survival rate from different linear models were low (0.01 to 0.09). The maternal heritability ranged from 0.00 to 0.04, and decreaced with increase in the age of lambs. The estimates of heritability in logarithmic scale, original scale and effective heritability obtained from the sire and animal models with Weibull function were medium to high (0.08 to 0.55) and were higher than those estimated through different linear models. The maternal heritability estimated through Weibull models decreased with the age of lambs (0.25 to 0.01). These results indicated that the accuracy of the Estimated Breeding Values (EBV) of lambs' survival rate from birth up to yearling age, using linear animal models vs. proportional hazard models, would be low vs. medium to high, respectively. Both animal and maternal genetic effects should be considered in the models for improving the survival rate up to 4 months of ages.

Vatankhah M.,Agriculture and Natural Resources Research Center | Talebi M.A.,Agriculture and Natural Resources Research Center | Zamani F.,Agriculture and Natural Resources Research Center
Small Ruminant Research | Year: 2012

The data set used in this study consisted of 1099 records of body condition score (BCS) and respective reproductive and productive traits from 442 ewes, recorded over a 3. year (2006-2008) period, of a Lori-Bakhtiari research flock at the Shooli station. The aim was to determine the relationship of BCS with reproductive and productivity performance. Body condition scoring was assessed 1-2. days before mating, based on a scale of 1-5, by palpation of muscling and fat deposition over and around the vertebrae in the loin region. The data set was analyzed using a model that included BCS, as well as other factors that affected reproductive and productive traits. The results showed that the overall mean ewe body condition at mating was 2.6, the highest relative frequency (32%) being observed for a BCS of 2.5. Of the total ewes, 62.1% recorded a BCS of between 1 and 2.5. The effect of ewe BCS was significantly (P<0.01) related to ewe body weight, reproductive traits (conception rate, litter size at birth, weaning rate, number of estrous cycles to conception in each season) and the ewe's productivity (total litter birth weight and weaning weight per ewe exposed). Ewe body weight at mating increased by 3.1. kg with each increasing unit of BCS. The least square means for most of the reproductive and all of the productive traits increased, with increasing ewe BCS - reaching maximum values at a BCS of 3.5 and then decreasing in the presence of other factors affecting these traits. For most of the considered traits, the differences between ewes with a BCS of 3 and 3.5 were low and not significant (P>0.05). It is therefore recommended to maintain the BCS of ewes at mating in the range of 3-3.5, to optimize the profitability of flocks in this breed. © 2012 Elsevier B.V.

Modarres Najafabadi S.S.,Agriculture and Natural Resources Research Center
International Journal of Acarology | Year: 2012

The quality of the host plant affects the development and survival of two-spotted spider mite (TSSM) Tetranychus urticae Koch. The biology and fertility life tables of T. urticae on six cultivars of common bean (Phaseolus vulgaris L.) (chiti Khomein, chiti Ks21189, red Akhtar, red Ks31169, white Pak and white G11867) were studied at constant laboratory conditions (272C, 705% relative humidity and 16L:8D h). Immature developmental times of male and female mites were significantly influenced by bean cultivars. This time was significantly longer on white Pak and white G11867 than on the other cultivars, whereas total fecundity per female was higher on red Akhtar than the other cultivars. There were significant differences among the forms of the survival curves of mites on the bean cultivars. Statistical comparisons of the jackknifed intrinsic rate of natural increase (rm), net reproductive rate (R 0), generation time (T), doubling time (DT) and finite rate of increase () suggest unsuitability of the cultivars white Pak and white G11867 as hosts for the development of TSSM. rm, R 0 and of the T. urticae had the highest value on red Akhtar and the lowest on white Pak and T and DT varied significantly on different cultivars and the shortest and longest values were obtained on red Akhtar and white Pak, respectively. The lower population rate of the mite could be the result of antibiotic resistance in the cultivars white Pak and white G11867. © 2012 Copyright Taylor and Francis Group, LLC.

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