اهداف اصلاحی گوسفند کردی استان ‌کردستان در سیستم روستایی

هدف از پژوهش کنونی، بررسی سامانه پرورش و تحلیل هزینه-فایده گله‌های گوسفند کردی مناطق کوهستانی استان کردستان در شرایط پرورش روستایی و همچنین برآورد ارزش اقتصادی صفات و تعیین اهداف اصلاح نژاد بود. به همین منظور، در یک دوره کامل تولیدی، هفت گله گوسفند کردی تیپ کوهستان برای جمع‌آوری اطلاعات دقیق از سامانه پرورش، تحت پوشش و بررسی قرار گرفتند. فراسنجه‌های مورد نیاز برای تجزیه و تحلیل در مدل مورد استفاده شامل: ساختار گله، متغیرهای تولیدی، متغیرهای مدیریتی، متغیرهای غذای مصرفی، هزینه‌های مدیریت، هزینه‌های بازاریابی، هزینه‌های ثابت و قیمت‌ها مستقیماً از گله‌های تحت پوشش، بازار و یا منابع علمی استخراج و استفاده شدند. داده‌های جمع‌آوری شده جهت برآورد ارزش های اقتصادی، وزن اقتصادی، اهمیت نسبی صفات، تجزیه و تحلیل حساسیت ارزش های اقتصادی و تعیین اهداف اصلاحی مورد استفاده قرار گرفتند. بازده خالص تولیدمثل در این نژاد برابر با 0.54 و سود حاصل از هر راس میش در هر سال برابر با 11313953 ریال و نسبت درآمد به هزینه و نسبت هزینه به درآمد به ترتیب برابرب با 1.38 و 0.73 بودند. بررسی وزن اقتصادی صفات نشان داد صفات میزان آبستنی، تعداد بره‌‌ها در هر زایمان میش، زنده‌مانی بره تا شیرگیری، فراوانی بره‌زایی، زنده‌مانی بره از شیرگیری تا فروش، وزن بره در زمان فروش، وزن بلوغ میش (با ضریب منفی)، زنده‌مانی میش، وزن جایگزین‌ها (با ضریب منفی) و تولید پشم به ترتیب دارای بیشترین اهمیت بودند. صفات مذکور را بر اساس این رتبه‌بندی و برای افزایش سودآوری گله‌ها می توان در برنامه‌های اصلاح نژادی گوسفند کردی در نظر گرفت.

breeding objectives for kurdi sheep of kurdistan province in the village system

introduction: 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.materials and methods: 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.results and discussion: 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.conclusions: 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.materials and methods: 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.results and discussion: 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.conclusion: 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.