TY - JOUR ID - 28535 TI - Economic Aspects of Mature Body Weight and Age at First Calving in Holstein Dairy Cattle of Iran JO - Iranian Journal of animal Science JA - IJAS LA - en SN - 2008-4773 AU - sadeghi, ali AU - moradi shahre babak, mohamad AU - nejati javaremi, ardashir AU - mirayi ashtiani, seyed reza AU - arimer, piter AU - jan bern, temti AU - taghi nejad, mahdi AD - Y1 - 2012 PY - 2012 VL - 43 IS - 2 SP - 269 EP - 278 KW - modeling KW - Production costs KW - selection Index DO - 10.22059/ijas.2012.28535 N2 - The aim followed in the present study was to investigate the economic aspects of , and to derive Economic Weights (EWs) for Mature Body Weight (MBW) as well as for age at First Calving (AFC) in Holstein dairy cattle of Iran. Economic values (EVs) for traits were estimated using trait-by-trait bio-economic models. Absolute EVs were RLs -16400 and -17900 per cow per year for MBW and AFC, respectively. Because of the negative effects of these traits on profitability, EWs of -7540 for MBW and -3760 for AFC are suggested for a national selection index. A one day increase in AFC increased production costs by Rls 39600 per cow per year. Sensitivity analysis revealed that the EV for MBW was more sensitive to changes in live weight price than to feed costs. Results obtained in this study can be used in the development of breeding objectives and in the cost- benefit analysis of management programs which aim at changing the attitudes of farmers and of their consultants towards decreasing costs and therefore increasing profitability. UR - https://ijas.ut.ac.ir/article_28535.html L1 - https://ijas.ut.ac.ir/article_28535_09326a4fda49156b63ffc0d73f79f882.pdf ER -