R. Bras. Zootec.. 01/Aug/2016;45(8):489-98.
Dorper sheep utilizing feed resources efficiently: a Mediterranean case study
The aim of the study was to determine the effect varying feeding systems would have on meat quality and production. The study looked at 45 Dorper lambs which were subjected to three different feeding protocols representing three alternate production systems: extensive grazing system (Group G), an intensive feedlot system being fed concentrate + alfalfa hay (Group C), and a semi-intensive production system comprising grazing + concentrate (Group GC). The lambs were slaughtered 62 days after weaning at approximately four months of age and meat quality factors such as pH, colour, shear force, cooking and water loss, as well as carcass characteristics; back fat thickness, muscle depth, muscle width, and muscle area were measured instrumentally on the longissimus dorsi muscle. A new measuring index was used to assess feed cost against weight gain to determine performance for profitability. In calculating cost kg-1 live weight gain, the extensive grass-fed production was significantly lower, approximately 70% less than the intensive feedlot system. Very little significant effect on meat quality was seen among the three systems. Slaughter weight had a significant effect on hot carcass weight, cold carcass weight, and drip loss. The lean carcass trait of the Dorper breed was a major positive attribute, but minor benefits gained in meat quality with the feedlot production system did not justify the substantial additional cost of production. Dorper sheep can be considered efficient feed converters on pasture, and thus a suitable breed for lamb meat production in countries like Turkey, where feed costs are the main contributor to farm outgoing.