Development of new pig carcasses classification formulas and changes in the lean meat content in Latvian pig population

摘要

Pig classification is based on objective estimation of the lean meat content of the carcasses. The European Union established a common framework for the classification of pig carcasses. Carcass classification serves as a quality development tool to encourage the breeding of animals, from which it is possible to get high quality carcasses for processors and consumers. It is a common practice to recalculate pig carcasses classification formulas and update existing classification methods (or develop new methods) after every five years.The representative samples of 145 pig carcasses from all regions of Latvia were used for the dissection trial. The precisely dissected carcasses with the warm carcass weight 60–110 kg were selected according to fat thickness and gender of pigs (the sex ratio were 50% females and 50% castrated males). From the experimental data were developed new formulas for the four methods Intrascope (Optical Probe); Manual method (ZP); Pork Grader (PG200); Optigrade MCP. During sampling the average warm carcass weight was 89.31 kg. New coefficient was detected and formula was developed for calculation of carcass standard presentation in all cases if some of the carcass parts are missing; for the missing head 8.345, for the missing tail 0.072, for the missing forefeet 0.764, for the missing hind feet 1.558. The comparison between the currently used and new experimentally obtained formulas showed difference up to 1.86% in lean meat content. The results suggest high accuracy of new regression formulas, which fully meets requirements of EU legislation.