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

Abstract: The subject of the current research was to calculate profitability and economic values of production and functional traits in sheep of Bulgarian dairy synthetic population, reared at the Agricultural Institute – Stara Zagora. The study period was 7 years (2010-2016) and the average annual number of ewes in the flock was 188. The semi-intensive production system practised involved winter indoor lambing and summer grazing on pasture. Data were processed using the Program for calculating economic weights for sheep EWSH2. Profit and profitability in the flock had negative values – (-52.70 BGN) and -19.3%. Marginal economic values of the most important traits in dairy sheep – milk production and number of lambs born per ewe were estimated to 0.707 BGN per liter and 65.40 BGN per lamb, respectively. Litter size, milk yield, conception rate of ewes and ewe lambs and productive lifetime of ewes showed the highest economic importance. A very low economic weight was calculated for the wool production due to the market prices of wool. Conception rate of female animals and productive lifetime of ewes need to be more thoroughly investigated, as they are not currently an object of selection in dairy sheep breeding. Achieving competitive and economically sustainable productive systems in sheep farming is associated with a constant desire to increase the economic value of animals.

Download Full-text

Current challenges for trait economic values in animal breeding

Czech Journal of Animal Science ◽

10.17221/161/2020-cjas ◽

2020 ◽

Vol 65 (No. 12) ◽

pp. 454-462

Author(s):

Zuzana Krupová ◽

Emil Krupa ◽

Ludmila Zavadilová ◽

Eva Kašná ◽

Eliska Žáková

Keyword(s):

Feed Efficiency ◽

Ghg Emissions ◽

Selection Response ◽

Animal Production ◽

Animal Breeding ◽

Animal Performance ◽

Economic Values ◽

Breeding Values ◽

Breeding Objective ◽

Economic Selection

Modern selection approaches are expected to bring about the cumulative and permanent improvement of animal performance and profitability of animal production. Breeding values of traits along with trait economic values (EVs) are utilised for economic selection purposes with many species all over the world. Currently, some challenges related to trait EVs in animal breeding should be considered. First, the selection response based on the higher accuracy of genomic selection may be reduced due to improper weighting of the trait breeding values of selection candidates. A comprehensive approach applied in bioeconomic models allows suitable trait EV calculations. Further challenges comprise the new breeding objectives associated with climate change, environmental mitigation and animal adaptability. The estimation of EVs for traits influencing greenhouse gas (GHG) emissions has been mostly based on including the value of CO<sub>2</sub> emission equivalent in the trait EVs, on calculating EVs for feed efficiency traits and on methane yield as a direct trait of GHG emission. Genetic improvement of production, functional, feed efficiency and methane traits through the application of multi-trait selection indices was found to be crucial for mitigation of emissions and farm profitability. Defining the non-market values of traits connected with climate protection could be a useful solution for including these traits in an economic breeding objective. While GHG emissions mostly change the costs per unit of production, animal adaptability in its complexity influences animal performance. Clear definitions of disease, fertility, mortality and other breeding objective traits allow the proper calculation of trait EVs, and an accurate estimation of trait genetic parameters could lead to sufficient economic selection response. This complex approach could be beneficial for more effective utilisation of inputs and overall economic and environmental sustainability of animal production.

Download Full-text