Impact of production strategies and animal performance on economic values of dairy sheep traits

Abstract

The objective of this study was to carry out a sensitivity analysis on the impact of various production strategies and performance levels on the relative economic values (REVs) of traits in dairy sheep. A bio-economic model implemented in the program package ECOWEIGHT was used to simulate the profit function for a semi-extensive production system with the Slovak multi-purpose breed Improved Valachian and to calculate the REV of 14 production and functional traits. The following production strategies were analysed: differing proportions of milk processed to cheese, customary weaning and early weaning of lambs with immediate sale or sale after artificial rearing, seasonal lambing in winter and aseasonal lambing in autumn. Results of the sensitivity analysis are presented in detail for the four economically most important traits: 150 days milk yield, conception rate of ewes, litter size and ewe productive lifetime. Impacts of the differences in the mean value of each of these four traits on REVs of all other traits were also examined. Simulated changes in the production circumstances had a higher impact on the REV for milk yield than on REVs of the other traits investigated. The proportion of milk processed to cheese, weaning management strategy for lambs and level of milk yield were the main factors influencing the REV of milk yield. The REVs for conception rate of ewes were highly sensitive to the current mean level of the trait. The REV of ewe productive lifetime was most sensitive to variation in ewe conception rate, and the REV of litter size was most affected by weaning strategy for lambs. On the basis of the results of sensitivity analyses, it is recommended that economic values of traits for the overall breeding objective for dairy sheep be calculated as the weighted average of the economic values obtained for the most common production strategies of Slovak dairy sheep farms and that economic values be adjusted after substantial changes in performance levels of the traits.

Influence of selected factors on growth performance of Suffolk lambs and their crossbreds

“…All these factors are closely connected to flock economy which is documented by partial economic values expressed by Wolfová et al (2009) or Krupová et al (2012). Moreover the flock profitability in Suffolk sheep population in Czech Republic is profitable only with governmental subsides 15.3 € or 15 % expressed by profit to costs ratio.…”

Impact of variation in production traits, inputs costs and product prices on profitability in multi-purpose sheep

“…These values were based on own investigations on sheep farms and records in the database of the Breeding Service of the Slovak Republic (unpublished data). Further characteristics of the production system can be found in Krupová et al (2009Krupová et al ( , 2012.…”

“…Production and economic data of these farms were close to the average values over the whole population of the Improved Valachian breed in Slovakia. Averages of those factors over the time period 2004 to 2010 are presented in Table 2 mic parameters used for the calculation can be found in Krupová et al (2009Krupová et al ( , 2012. Additional biological, production and economic parameters whose levels were varied in comprehensive analyses are presented in Table 3.…”

Review of Methodologies for Costs Calculating of Ruminants in Slovakia

“…Tabuľka 3 Prehľad nákladových položiek kalkulačného vzorca a ich relatívny podiel na celkových nákladoch kategórie (%) Table 3 Review of the individual items of costing formula and relative proportion of the total cost in category (%) Kategórie zvierat (1) Dojnice (2) Dojčiace kravy (3) Ovce (4) Autor (5) Daňo et al (2010aDaňo et al ( , 2010b, Poláčková et al (2006), Boudný (2010), Vláčil (2005), Krupová et al (2011c).…”