فهرست مطالب m. vatankhah

The first step in designing livestock breeding programs is to decide on appropriate breeding objectives. The most significant factor in the inefficiency of livestock breeding programs is the undesired breeding goals, which causes the selection pressure to be applied to the wrong traits. The production system, market conditions, and flock competence cause the breeding goals to be different from each other. This research was conducted to investigate the production system and cost-benefit analysis of Kurdi sheep flocks in the mountainous regions of Kurdistan province under the conditions of village breeding, as well as estimate the economic values and relative importance of traits and determine the breeding goals of this breed.
In an entire production period, seven flocks of Kurdi sheep of the mountain type were covered and investigated to collect detailed information about the breeding system. The parameters required for analysis in the used model include flock structure, production variables, management variables, feed consumption variables, management costs, marketing costs, fixed costs, and prices gathered directly from the covered flocks, market, and scientific sources. The collected data were used to estimate the economic values, economic weights, and relative importance of the traits and determine the breeding goals. In this study, the economic value of traits was calculated using a deterministic static model, and the total annual profit of the flock was calculated by deducting the costs from the system's revenues under survey. The economic values of each trait were defined as a change in the profit obtained per one-unit increase in the desired trait while keeping other traits constant at the population average. The economic weights of traits were also calculated by multiplying the economic value of each trait by the genetic standard deviation of that trait. After determining the relative importance of the traits, the traits present in the breeding goals were determined in order.
The study of the dynamics of Kurdi sheep flocks, and their reproduction and survival characteristics in the conditions of rural farming showed that the survival rate of ewes, pregnancy rate, frequency of lambing, and litter size were 97%, 84%, 20%, and 1.08, respectively, and the rates of lamb survival until weaning and after that were 85% and 96%, respectively. In this way, the number of weaned and salable lambs per head of breeding ewe were 0.90 and 0.54, respectively. The cost-benefit analysis of sheep flocks showed that the costs of feeding, labor, veterinary services, fixed, transportation of animal feed, and marketing were 55.7%, 21.5%, 15.6%, 4.7%, 1.8%, and 0.7% of the total costs, respectively. Meat was the first with 99.5%, and wool with 0.5% was the second source of flocks’ income. The profit from each head of breeding ewe per year was 11313953 Rials, and the ratio of income to cost and the ratio of cost to income were 1.38 and 0.73, respectively. The absolute economic values were positive for all investigated traits except for the live weight traits of the replacements, and the culled mature ewes. Calculation of economic weight and relative importance of traits showed that reproductive traits, survival traits, and productive traits were important, respectively. The traits of pregnancy rate and litter size were the most important, and the live weight of replacements and wool production were the least important in increasing profitability or reducing costs.
The efficiency of each head of breeding ewe compared to costs was calculated as 38%, which has increased by about 3% compared to the last four years. These figures showed that the profit from each head of breeding ewe is noticeable, and the policy of freeing the price of livestock inputs in recent years has not had a significant effect on the profitability of Kurdi sheep breeding in rural conditions. Of course, the number of salable lambs per head of breeding ewe as the net reproduction efficiency in this study was low, and with its improvement, the economic efficiency will also be better.  By examining each trait, it was determined that the breeding goals of this breed, in order of importance, included pregnancy rate, litter size, lamb survival until weaning, lambing frequency, lamb survival from weaning to sale, lamb live weight at sale, ewe live weight at maturity (with a negative value), ewe survival, replacements’ weight (with a negative value) and wool production. This ranking should be considered in breeding programs. In an entire production period, seven flocks of Kurdi sheep of the mountain type were covered and investigated to collect detailed information about the breeding system. The parameters required for analysis in the used model include flock structure, production variables, management variables, feed consumption variables, management costs, marketing costs, fixed costs, and prices gathered directly from the covered flocks, market, and scientific sources. The collected data were used to estimate the economic values, economic weights, and relative importance of the traits and determine the breeding goals. In this study, the economic value of traits was calculated using a deterministic static model, and the total annual profit of the flock was calculated by deducting the costs from the system's revenues under survey. The economic values of each trait were defined as a change in the profit obtained per one-unit increase in the desired trait while keeping other traits constant at the population average. The economic weights of traits were also calculated by multiplying the economic value of each trait by the genetic standard deviation of that trait. After determining the relative importance of the traits, the traits present in the breeding goals were determined in order. The study of the dynamics of Kurdi sheep flocks, and their reproduction and survival characteristics in the conditions of rural farming showed that the survival rate of ewes, pregnancy rate, frequency of lambing, and litter size were (97%), (84%), (20%), and (1.08), respectively, and the rate of Lamb survival until weaning and after that were (85%) and (96%), respectively. In this way, the number of weaned and salable lambs per head of breeding ewe were (0.90) and (0.54), respectively. The cost-benefit analysis of sheep flocks showed that the costs of feeding, labour, veterinary services, fixed, transportation of animal feed, and marketing were (55.7%), (21.5%), (15.6%), (4.7%), (1.8%), and (0.7%) of the total costs, respectively. The meat was the first, with (99.5%), and produced wool, with (0.5%), was the second source of flocks’ income. The profit from each head of breeding ewe per year was (11313953) Rials, and the ratio of income to cost and the ratio of cost to income were (1.38) and (0.73), respectively. The absolute economic values were positive for all investigated traits except for the live weight traits of the replacements, and the culled mature ewes. Calculation of economic weight and relative importance of traits showed that reproductive traits, survival traits, and productive traits were important, respectively. The traits of pregnancy rate and litter size were the most important, and the live weight of replacements and wool production were the least important in increasing profitability or reducing costs. The efficiency of each head of breeding ewe compared to costs was calculated as (38%), which has increased by about (3%) compared to the last four years. These figures show that the profit from each head of breeding ewe is noticeable, and the policy of freeing the price of livestock inputs in recent years has not had a significant effect on the profitability of Kurdi sheep breeding in rural conditions. Of course, the number of salable lambs per head of breeding ewe as the net reproduction efficiency in this study was low, and with its improvement, the economic efficiency will also be better. By examining each trait, it was determined that the breeding goals of this breed, in order of importance, include pregnancy rate, litter size, lamb survival until weaning, lambing frequency, lamb survival from weaning to sale, lamb live weight at sale, ewe maturity live weight (with a negative value), ewe survival, replacements weight (with a negative value) and wool production. This ranking should be considered in breeding acts and programs.

The purpose of this study was to investigate the effectiveness of mindfulness-based cognitive therapy on executive functions and emotion regulation in overweight and obese adolescents. The present study is a pre-test, post-test with control group. The statistical population of the study consisted of obese and overweight male students in Isfahan who referred to health centers in Isfahan city in 1397. The sample consisted of 36 obese and overweight male students who were selected by convenience sampling from those referring to health centers in Isfahan. Research tools including Graz and Romer emotion regulation difficulty questionnaire, Wisconsin and Stroop test were used to measure executive functions. The results showed that mindfulness-based cognitive therapy was effective on BMI, emotion regulation and executive functions (p <0.001) but was not significant in interaction with BMI (p> 0.05). These findings may explain the utility of mindfulness-based approaches to adolescent obesity by influencing the executive functions of the brain and emotion regulation of adolescences.

Crossbreeding is used in order to take advantage of the different and complementary strong points of two or more breeds and to utilize hybrid vigor. In this study the results of sheep crossbreeding have been reviewed from published over the last years in Iran. The results showed that much of the crossbreeding in the sheep industry in Iran due to incorrect selection of breeds was not suitable. The main disadvantages points of Iranian sheep are low reproduction performance, low longevity, insufficient growth rate, unsuitable carcasses composition and feed efficiency, respectively. While, in the most crossbreeding schemes have been done between Iranian breeds of sheep, focused on improve growth traits and reduced fat-tail weight, which created low and no significant changes in crossbreds for these traits, leading to reducing economical efficiency and unsustainable of rearing sheep in semi-intensive or village system over last years. Sustainability could been achieved by combining desirable characteristics from the indigenous breeds to keep fitness and marketability with those of specialist exotic breeds that had already demonstrated genetic potential for traits of economical importance for commercial production. However, research findings suggested that in well-planned efforts to create composite breeds (with minimum 50% native) using the prolific breeds (such as Romanov), with high mothering ability, low maturity age, suitable carcass composition and medium ewe body weight could increased productivity of sheep in village system in Iran.

Gingival overgrowth is a common clinical finding that most often represents reactive hyperplasia as a result of inflammatory gingival disease related to dental plaque. Irritation fibroma (IF), pyogenic granuloma (PG), peripheral ossifying fibroma (POF), and peripheral giant cell granuloma (PGCG) are non-neoplastic enlargements of the gingiva that are categorized as reactive hyperplastic lesions. Most of these lesions have a similar clinical appearance, i.e., a sessile or pedunculated nodule at the interdental papilla; the color varies from pale pink to red. All reactive gingival lesions show some variations in terms of gender, type, location, duration, and histologic features. Here, we present a case of PGCG in a 10-year-old male with its clinical presentations as well as radiological and histological features along with the management procedure. Choice of treatment for our case was surgical excision, fluoride therapy, and oral hygiene maintenance. The patient remained tumor-free for 18 months and is still on regular follow-up.

One of the breeding programs for sheep is the nucleus breeding scheme (Kosgey and Okeyo 2007). The nucleus breeding system, including open or close nucleus, is a good start for genetic improvement in many populations. Unlike the close nucleus schemes, there is a reciprocal gene flow in open nucleus schemes, where the best animals from base layer could be transferred to the nucleus layer (Kosgey et al. 2006). In the original nucleus breeding scheme, a constant genetic variation was assumed for the trait of interest across different generations (Hopkins and James 1978). However, it is well realized that the additive genetic variance is decreased after several generations of intense selection. Thus, the actual genetic gain is likely less than the expected genetic gain. In other words, the outcomes of these breeding schemes are likely affected by the intensity of selection as well as the relative size of the nucleus population to the size of whole population. The aim of current study was to investigate the effect of relative nucleus size at three levels of 5, 10 and 15 percent and the effect of selection intensity in males and females at three levels of high (i.e. selection proportion in male and female candidates were 1 and 20 percent, respectively), moderate (i.e. selection proportion in male and female candidates were 5 and 50 percent, respectively) and weak (i.e. selection proportion in male and female candidates were 10 and 80 percent, respectively) on the amount of biasness of predicted genetic gain due to ignoring the effect of selection on genetic variance. An open nucleus breeding scheme was deterministically simulated using data from Lori Bakhtiari sheep breed, consisting a nucleus herd of 1005 ewes and a base herd of 4019 ewes (Vatankhah 2005). Birth weight was the breeding goal trait and selection was carried out using one individual performance record. The generation was assumed to be overlapped and three and six age groups were considered for males and females, respectively. The age of parents at first lambing was 2 years and 0.94 yearling lamb was produced per ewe. One ram was mated to 33 ewes. The additive genetic variance for breeding goal trait was 0.11 and its heritability was set to 0.30. For a given size of the nucleus and a constant rate of transferring ewes from base population to nucleus (x), there was an optimum rate of migration of nucleus rams into the base population (w), that maximized the expected genetic gain and minimized the genetic lag between nucleus and base populations, with or without accounting for the effect of selection on the genetic variance. By increasing the relative size of the nucleus, from 5 to 15 percent of whole population, the biasness of the predicted genetic gain was increased from 11.84 to 16.67 percent. At a given rate of x, the bias of genetic gain prediction which originated from ignoring the effect of selection, varied nonlinearly as the rate of w increased and had a minimum value at the optimal value of w. At a particular rate of w, increasing the rate of x, was associated with higher rate of bias. The rate of bias increased from 12.2 to 16.54 percent, as the intensity of selection increased. The reason could be the markedly reduction in the genetic variance of considered trait due to selection at high selection intensities. In open nucleus schemes, the amount of bias changed from 14.18 to 17.72, as a consequence of increasing the intensity of selection. Across all levels of selection intensity in open nucleus programs, the lowest bias was observed at the rate of 0.75 for w. Evaluation of joint effect of relative nucleus size and intensity of selection, showed that at high selection intensity and relative nucleus sizes higher than 10 percent, the amount of bias was not likely to be influenced by nucleus size. Ignoring the effect of selection on genetic variance could result in a biased prediction of genetic gain in the nucleus breeding schemes. However, the optimal ram transfer rate from nucleus to base population was independent from the effect of selection intensity. The lowest bias was observed for the scheme with optimum transfer rate. Results of the current study revealed that at weak selection intensity, the effect of selection could be ignored and the breeding program could be optimized for ram transfer rate from nucleus to the base populations. However, at high selection intensities, the ignorance of this effect might result in wrong conclusions.

In this research 5633 records, which collected by Khojir Sheep Breeding Station of Tehran, during the 1994 to 2011 were used for estimate of (co)variance component and evaluation of inbreeding effects on birth weight (BW) and pre weaning mortality (PMW) in Zandi lamb. Genetic parameters were estimated using REML procedures. AIC criterion test were used to choose the most suitable model. The most suitable animal model for BW included direct additive genetic, maternal additive genetic, maternal permanent environmental and common litter effects, and suitable model for PMW were included direct additive genetic, maternal additive genetic and common litter effects. Also suitable threshold model was included sire additive genetic effects and litter effects, but the most appropriate sire model only including sire additive genetic effect. Direct and maternal heritability for BW was 0.11 and 0.08, respectively. Also, logit heritability and heritability obtained from threshold, animal and sire models were 0.14, 0.20 and 0.18, respectively. Genetic, environmental and phenotypic correlation between BW and PMW was -0.27, -0.23 and -0.28, respectively (p<0.05). The 27 percent of all animals in population were inbred. The mean of inbreeding coefficients in population and inbreed animals were 3.5 and 0.9 percent, respectively. The estimates of inbreeding depression were -3.5 g for BW and 0.1 percent for mortality, respectively (p<0.05).

Genetic parameters of body weight using random regression model were estimated using 22881 live body weight test day records collected on 6599 lambs during 1990 to 2007 at the rearing and Kurdi sheep breeding station in Shirvan. The model was included fixed effects (year of birth، sex of lamb، birth type of lamb and age of dam) and random effects direct additive genetic، maternal additive genetic، permanent environmental and residual. Random regression models were fitted with order 2 to 6 for direct additive genetic، maternal additive genetic and permanent environmental effects. Results indicated that the 6th order was more appropriate than others. The values of direct heritability with this model for lamb body weight at birth، 2، 3، 4، 5، 6، 7، 8، 9، 10، 11 and 12 months of age were estimated as 0. 06، 0. 27، 0. 31، 0. 35، 0. 35، 0. 33، 0. 30، 0. 28، 0. 27، 0. 28، 0. 29 and 0. 28 respectively. The values of maternal heritability with this model were estimated as 0. 24، 0. 03، 0. 06، 0. 09، 0. 10، 0. 12، 0. 13، 0. 12، 0. 11، 0. 10، 0. 10 and 0. 08 respectively. The proportion of permanent environmental variance to phenotypic variance was increased from 0. 05 for birth weight to 0. 69 for body weight at 2 months of age، up to 5 months of age reduced and then increased with increasing age of lamb. Direct and maternal genetic correlations between body weights at different ages were positive and ranged from 0. 16 to 0. 99 and 0. 25 to 1. 00، respectively، at closer ages were higher and decreased with increasing intervals age. In general the results obtained in this study suggested that lamb body weight were influenced by different factors (direct and maternal additive genetic and permanent environment)، and due to various estimated heritability for lamb body weight from birth to 12 months of age، it could be concluded that some different genes might be affect lamb body weight at birth to 12 months of age.

Data and pedigree information for Lori-Bakhtiari sheep used in this study were 6241 records of lamb survival from 1721 dams and 246 sires collected from 1989 through 2007، from a Lori-Bakhtiari flock at Shooli station in Shahrekord. To estimate the effect of environmental factors on survival lambs used GLM procedure from SAS. The models included fixed factors that had significant effects and random direct genetic، maternal genetic and residual effects. Genetic parameters were estimated using restricted maximum likelihood procedure applying univariate animal models with and without maternal effects and repeatability model. Results showed that the overall mean of cumulative lambs’ survival were 0. 98، 0. 97، 0. 97، 0. 95، 0. 94، 0. 90، 0. 82، 0. 78، 0. 75، 0. 72، 0. 69، 0. 68، 0. 68، and 0. 68 from birth up to 7، 14، 21، 30، 60، 90، 120، 150، 180، 210، 240، 270، 300، 330 and 365 days of age، respectively. The age of dam، sex of lamb، year of birth and birth weight of lamb as covariate had a significant (p<0. 05) effect on lamb survival، but the type of birth was not significant. The least square means of lamb survival increased with age of dam and then decreased in dams with more than 5 years old. The least square means of lambs’ survival in females was higher than the male lambs from birth up to 12 months of age. The birth weight of lamb had a highly significant (P≤0. 01) effect on lamb survival at all ages as quadratic regression. Direct and maternal heritability estimates of lamb survival ranged from 0. 01 to 0. 22 and 0. 01 to 0. 04، respectively. Direct heritability increased with age of lamb، while maternal heritability decreased. The repeatability estimate of lamb’s survival from birth to 12 months of age was 0. 48.

In this study 5025 records from the Lori-Bakhtiari sheep stud were used to predict phenotypic, genetic and environmental change in ewe traits from 1989 to 2004. Best linear unbiased prediction (BLUP) of breeding values were estimated by Drivative Free Restricted Maximum Likelihood (DFREML) procedure using single and multi-trait animal model. Phenotypic, genetic and environmental trends were calculated by regressing of the average phenotypic values, predicted breeding values and environmental values in the year of ewe birth respectively. The estimated phenotypic trends were –0.1223 kg for ewe body weight, -0.0415 kg for greasy fleece weight, 0.6639% for conception rate, 0.0003 for number of lambs born per ewe lambing, 0.0094 for number of lambs weaned per ewe lambing, 0.0380 kg for total birth weight per ewe exposed and 0.4227 kg for total weaning weight per ewe exposed. The estimated genetic trends were 0.0603 kg, -0.0004 kg, 0.0183%, -0.0012, -0.0007, 0.0030 kg and 0.0211 kg from single trait analysis and 0.0549 kg, -0.0006 kg, 0.0089%, -0.0008, -0.0008, 0.0030 kg and 0.0230 kg respectively from multi-trait analysis. The estimated phenotypic and environmental trends were significant but genetic trends were not significant (P<0.05) for often traits.

In this study external fat-tail dimensions (upper, middle and lower width, length, length of gap, depth and upper circumference) and fat-tail weights collected on 724 Lori-Bakhtiari sheep were used to study external fat-tail dimensions and their relationships with fat-tail weights. Sheep were 3 months to 6 years old and slaughtered at the industrial slaughter house of Joneghan in Chaharmohal and Bakhtiari province in 2003. The mean of fat-tail dimensions were estimated as 15.83, 23.85, 24.73, 26.52, 14.96, 14.12 and 52.59 cm for upper width, middle width, lower width, length, length of gap, depth and upper circumference, respectively. Fat-tail weight varied from 0.10 to 20.60 with overall mean of 2.71 kg. Fat-tail percentage varied from 1.18 to 37.18 with overall mean of 11.87 percent. The effects of fixed factors of age, sex and body condition of sheep on all of traits were highly significant (p<0.0001). The least square means of all traits except fat-tail percentage were increased with increasing age of sheep. Lowest least square mean (± s.e) of 2.12 ± 0.25 kg fat-tail weight and 7.91 ± 0.72% fat-tail were observed for sheep having body condition score of 1 and the highest least square mean with fat-tail weight of 9.84 ± 0.56 kg and fat-tail percentage of 20.59 ± 1.63 were observed for sheep having body condition score of 5. Estimation of correlation coefficients among external fat-tail dimensions and fat-tail weight were positive and varied from 0.60 between upper fat-tail width and fat-tail weight to 0.83 between upper circomference of fat-tail and fat-tail weight. Upper circumference of fat-tail accounted for %69.5 of variation of fat-tail weight. This study showed that fat-tail weight in live sheep of Lori-Bakhtiari could be estimated using external fat-tail dimensions with very high accuracy (r = 0.904).

In this study 2510 records of reproductive traits from the mating of 879 ewes with 164 rams of Bakhtiari sheep breed, during 1989 to 1997, were used in order to estimate the effects of environmental factors on their reproductive performance. The mean and standard errors of reproductive traits were as follows: conception rate, 0.9±0.01 number of lambs born per ewe exposed, 1.06±0.01 number of lambs born alive per ewe exposed, 1.01 ±0.0l, number of lambs weaned per ewe exposed, 0.93±0.01 litter size alive at birth, 1.10±0.01 litter size at weaning, 1.01±0.02 and number of lambs weaned per lambing ewe, 1.09±0.01. The effect of joining year was highly significant (P, 0.01) for all of the considered reproductive traits. Age of ewe at joining time was also a significant (P<0.05 and 0.01) source of variation for most of the reproductive traits. Maximum reproductive performance occurred for ewes of 4 to 5 years of age. Mating time was also a significant factor (P<0.05 and 0.01) for all of the reproductive traits. Maximum reproductive performance occurred for ewes mated during the first half of the mating season. Type of birth was a highly significant factor (P<0.0l) for the number of lambs alive and weaning traits. However, due to significant effects of environmental factors on considered traits, and in order to increase reproductive efficiency, one should improve environmental conditions (barn, management, feeding system and ... ) as well as organizing mating plan for the first half of the mating season and make a suitable age combination of ewe herd. In this combination, decreasing the percentage of ewes older than five years could benefit herd performance.