جستجوی مقالات مرتبط با کلیدواژه « Economic values » در نشریات گروه « علوم دام »

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 aims of the present study were to estimate economic values and to determine breeding goals of functional traits of Lori sheep in the rural development system with two strategies, one lambing per year and three births in two years. For this purpose, functional parameters, management and economics of 32 flocks (according to Cochran's sample size formula) under the cover of a livestock breeding plan with a capacity of 3000 generative ewes from 2013 to 2015 were analyzed for two production cycles using a bio-economic model. The performance data were obtained from Animal Breeding Center of Iran and management and economic data were collected through preparation of a questionnaire and interviews with farmers. The results showed profit per head of ewe in the strategy of one lambing per year and three births in two years was 1723376 and 3429140, respectively. In both strategies, feeding considered more than 75 percent of total costs and the sales of meat with 98.5% had the highest percentage of total costs and revenues. In addition, in both strategies, relative economic coefficient of the number of lambs born per ewe had the highest relative economic value and wool produced for per ewe had the lowest relative economic value. Litter size and conception rate were the most important traits in the breeding objective for ewe in village system. Birth weight, weaning weight, yearling weight and survival at 3 and 12 months of age were the most important traits in the breeding objective for ewe lamb in village system. The strategy of three lambings in two years was superior to one lambing per year strategy due to the increase in the number of lambs for consumer sales.

The aims of interbreeding for the first level in planning interbreeding programs are generally maximize the improvement in the economical efficiency of the production system by means of increase the average of characteristics. The purpose of this research was to estimate the economic values for milk production traits, fat percentage, protein percentage, and lifetime of native cows of Ilam province and also consideration of their sensitivity to any change in productive and economical parameters in the production system.
Using a deterministic bio-economical model and economic and production parameters of Native cow, was estimated economic values of milk yield, fat percentage, protein percentage, herd life at the Ilam province in 2013. The economic values of each trait was estimated with increase of one unit of average traits used for the amount of annual profit change, so that were constant the other traits. Calculation of Revenues and Costs: Estimation of economical factors needs explanation of production system, revenue and costs sources and their relationship with existing characteristics for the aim of interbreeding. Costs are expressed as fixed and current. Current costs are depending on the level of cattle production. Fixed costs are independent of production level and including building and installations, machinery and so on.to calculate the nutritional costs for each age group of animals, four different levels according to the life style were defined by order. These levels include: from birth to weaning (bull calf and heifer before weaning),from weaning to selling age (bull calves in 8-months year old and heifers in 17 months of age, from selling age till the age of first delivery (for replaced heifers)and regenerator cows(over two years old). According to the definition, economical factor of each characteristic is described as a change in the net profit of factory for a unit of addition in the average considered characteristic in a way that the average of other characteristics in the population doesn’t change. In this research to calculate the economical factors of characteristics while other characteristics are in between in the population, the average for the considered characteristic was increased once by one unit and the difference of earned and profit or base mode was considered as the economical factor of that characteristic.
In the system of Native cows production, the economic values of milk yield, fat percentage, protein percentage, herd life were estimated 0.002079, 0.999782, 1 and - 0.000351 respectively. In the native cow's fostering system, revenue resources include annual sale of milk, bull calf, surplus heifer, annual, omitted regenerator cow and annual manure. Earned revenue out of annual milk sale equaled 43.54% of the total revenue which appropriated the greatest amount of revenue resources. Other revenue resources were including bull calf, surplus heifer and the sale of omitted cow that appropriated 11.23%, 32.37%, 10.04% and 2.81% of the revenues respectively. The costs were divided into two parts including annual fixed charge which contained the cost of building, installations, equipment and repairs. Annual current cost which contained nutritional costs, hygiene and reproduction, work force, cattle selling and transportation of manure from its place per each head of regenerator cow. Fixed annual cost per each head of regenerator cow equaled 4572556.56 Rial, which contained 14.44 percentage of the total costs .annual current cost per each head of regenerator cow equaled 27094514.46 Rials which appropriated85.56 percentage of the total cost. Among the current costs ,nutritional cost by 84.25% appropriated the most part .other current costs including workforce ,cattle sale and manure transportation from its place equaled 9.38% and costs of hygiene and reproduction appropriated 6.36% of the current costs.
Thus estimated the annual avenue of production system for Native cows -1801718.005 Rials. The results showed that positive amount of an economical factor to produce milk; selection of an average for an increase in the characteristic causes an increase in profiting in native cow's production system. According to the importance of interval in calving as a characteristic and specifically its influence in the situation of limitation in systems, it is suggested that interbreeding should be done to decrease it.

In this study production, reproduction, management and economic parameters obtained from 7 flocks with 600 head of native sheep were used during annual cycle of production in village systems. The economic values of traits were estimated using maximizing profit, revenue per cost and minimizing cost method. The results showed that the average profit per sheep per year, revenue per cost ratio and cost per revenue ratio for this system were 3,211,391Rials, 1.40 and 0.713, respectively. Feeding and husbandry costs represented about 64% and 20% of total cost, respectively. In maximizing profit method, average economic values (relative) of traits were 7,550.139 (1.102) Rials for survival rate, 7,630.49 (1.1143) Rials for conception rate, 7,172.632 (1.0475) Rials for lambing frequency, 6,520.575 (0.95228) Rials for lambing rate, 7,969 (0.9164) Rials for lamb survival rate to weaning, 8,150.719 (1.1903) Rials for kid survival rate to yearling, 6,847.3565 (1.00) Rials for lamb live weight at sale, -2610 (-1.93) Rials for body weight of sheep. In revenue per cost method the average economic values of aforementioned traits in all systems were 0.677, 0,683, 0.646, 0.592, 0.711, 0.726, 0.566, -0.293 respectively. The sensitivity of economic values to changes in prices of input parameters was low and to changes of prices in output parameters was high. Since the input parameters used in this study were collected from a wide range of management and climates conditions, estimated economic values could be used for designing the appropriate selection index for Kordi sheep.

In this study a bio-economic model was used for a flock with 195 breeding ewes and 20 rams to determine economic values of important traits in Zel sheep of Golestan including litter size, pre-weaning survival, post-weaning survival, ewe survival, birth weight, weaning weight, yearling weight, ewe mature weight, dressing percentage, conception rate and wool weight. In this model, fixed environment was assumed and herd profit was estimated from difference between costs and revenues. Relative economic values of the traits were estimated based on wool weight. The highest economic value was found for litter size with relative economic value of 139.82. After litter size, the most important relative economic values were 3.81 and 3.66 for ewe survival and dressing percentage, respectively. Economic values of all traits were positive except for birth weight (-0.98). Sensitivity analysis of economic values were carried out for 20% increase and decrease in price levels of input (concentrate, forage) and output (meat, wool) system. Economic values​​ of all traits except for birth weight and wool weight were changed by changing the price of meat. The economic values of ewe mature weight, dressing percentage and wool weight did not change with change in price of concentrate and forage .Sheep farming system can increase in profits by increasing in the amount and value of product. As the highest economic values were found for amount and value of the products especially amount of products, in order to increase system profit it is better to select for these traits in a breeding program.

In this study, production, reproduction, population, management and economic parameters resulted from recording of 12 industrial dairy farms with herd size 20 to 250 and a total of 1240 head of Holstein cows in a cycle of reproduction, during 2010 to 2012 were used to determine the economic values of important traits. The traits of economic importance that appeared in profit equation were durability traits (including survival rate in cow, calf to 3 months of age and heifer from 3 mo to parturition; cow and heifer weight and longevity of cow), health and reproduction traits (including conception rate, live birth rate, calving interval, calving difficulty rate, and age at first calving) and production traits (including calf weaning weight, weight of male fatten calf, milk, fat and protein yield). The economic values and the relative emphasis of traits estimated using maximizing profit by increasing one genetic standard deviation of each trait. The results showed that the sum of relative emphasis of different group of traits for different milk production levels were 38.15 to 36.05 percent for durability traits, 34.80 to 36.59 percent for reproduction and health traits and 27.05 to 27.80 percent for production traits, respectively. The relative emphasis of durability traits and reproduction and health traits decreasing and increasing respectively, with increasing milk production. The estimated relative emphasis of different traits, could be used to construct multiple trait selection indices in dairy cattle breeding programs.

The Harki sheep is a fat-tailed breed which medium- sized body and dairy- meat sheep. In this study parameters of production, reproduction and economic management obtained from data recorded for Harki sheep breed was evaluated in five flocks with 500 ewe during annual cycle of production in village system in 2012. Traits included; fertility, pregnancy rate, weight lambs from birth to the end of period, survival rate of lambs, wool production weight, average daily gain and milk production. A bioeconomic model was written for rearing system and flock information, economic values using maximum profit orientation was calculated by partial derivative of the profit function for a production system with one lambing per year by the Ecoweight software. To calculate economic values, change in system profit per unit change in the trait while was kept the other characters in the average, and was considered the average change in profit as an economic value. First all costs, revenues, profits and flock structure determined then intered input files and run the software. The relative economic values for birth weight, daily gain from birth until weaning, daily gain from weaning until end of period, conception rates ewes, little size, lamb survival at weaning, lifetime, milk yield during the standardized milking period of 150 d, milk fat, milk protein and fleece weight were 6.12, 0.68, 0.515, 2.36, 2.12, 2.54, 16.72, 3.54, 0.047, 0.024 and 1 respectively. Breeding objective in Harki sheep breed were productive lifetime, birth weight, milk yield, lamb survival at weaning, conception rates ewes, little size, wool yield, daily gain from birth until weaning, daily gain from weaning until end of period, milk fat and milk protein.

In this study production, reproduction, management and economic parameters resulted from recording 6 flocks with 1228 heads of breeding ewes during one year were used to determine the breeding objectives of Lori-Bakhtiari sheep in nomadic production system. A bio-economic model used to determine economic value for each trait in maximum profit, efficiency and minimum cost interests. For deriving economic weights, change in profit by one percent increase in mean of a trait, while all other traits werefixed at their means, were calculated and then divided by amount increased in that trait. To calculate the relative economic values, the absolute economic value of each trait was divided by the absolute economic value of the weight of wool. Sensitivity of economic weights to ±20 percentage changes in prices of costs and revenues were analysed. Economic analysis of system indicated that, costs, revenue, and profit per ewe per year were 1128200, 887255, and -240945 Rials, respectively. Labour costs with 55.7 % and revenue from live weight accounted for about 97.3 %, had the highest percentage of total costs and revenue, respectively. Feed and fixed costs represented about 36.9 % and 1.8 % of total costs, respectively. Lamb live weight at 5-month, litter size, lambing frequency, conception rate, lamb survival at birth, lamb survival from birth to 5 months, mature ewe live weight, fleece weight in ewes, ewe and replacement survival rate were represented in profit equation and accepted as breeding objectives. Relative economic values in maximum profit interest were, 2.64 for 5-month lamb live weight, 57.33 for litter size, 73.41 for lambing frequency, 97.88 for conception rate, 92.60 for lamb survival at birth, 113.96 for lamb survival from birth to 5 months, -0.067 for mature ewe live weight, 1 for weight of wool, 215.05 for ewe survival and 59.67 for replacement survival rate. It was concluded that litter size, lambing frequency, conception rate and survival rates, were the most important traits in breeding objectives. Sensitivity of economic weights with regard to meat price change was higher than the others.

To assess the economics of rural sheep production systems and estimation of economic values of important traits in Zandi breed, bio-economic approach was used. In order to estimate economical parameters for using in bio-economical equations and to calculate the EVs of traits, two farms with the flock sizes of 500 and 450 head of Zandi sheep breed in Varamin were studied since the beginning of September 2010 to September 2011. EVs (economic values) of six important traits including pregnancy rate (FE), litter size (LS), lamb weights at birth (BW0), 3 (weaning; BW3), 6 (BW6) months old and survival rate until the age of 6 months (SRL6) were estimated. To estimate the EV of each trait, the level of the trait was increased by both 1% of its mean value and 1 unit while all other traits were constant in their mean values and the amount of change in the profit of system was considered as the EV of the trait. The sensitivity of the EVs was investigated by changing prices of feed and live weight of animals by ±20%. The economic analysis results indicated that the average of feeding cost ratio to the overall costs; and also the average of management cost ratio to the overall costs of rural sheep production system were 64.5 and 33.2 percent respectively and the average annual profit of each breeding ewe in rural sheep production system was 1109594 Rials. The most important trait in this system was FE, followed by LS, BW6, SRL6, BW3 and BW0, respectively when used by 1% increase.