Factors affecting depth of muscle as a carcass quality parameter

By T. Cottrell, C. Dewey, R. Friendship, C. Ribble Department of Population Medicine, University of Guelph - This article is taken from the University of Guelph Swine Research Review 2005 report. Pigs produced with consistently large muscle depth are valuable for both the packer and the producer. The pork is more valuable for the packer because it meets the demands of the consumer.

5 December 2005

4 minute read

Factors affecting depth of muscle as a carcass quality parameter - By T. Cottrell, C. Dewey, R. Friendship, C. Ribble Department of Population Medicine, University of Guelph - This article is taken from the University of Guelph Swine Research Review 2005 report. Pigs produced with consistently large muscle depth are valuable for both the packer and the producer. The pork is more valuable for the packer because it meets the demands of the consumer.

Background

The producer is rewarded economically by receiving a higher dollar value for these pigs. However, producing a consistently lean, heavily muscled pig is difficult.

Objectives

To determine the farm-level factors associated with producing pigs with carcasses with large muscle depth.

Results

A survey of 90 farms was conducted to determine the relationship between farm-level factors and carcass quality as measured over a 2-year time period. All pigs were weighed prior to marketing by 47% of the producers and a further 32% of the producers weighed some of their pigs. On average, 58% of pigs were weighed before marketing. Most producers used a single source of genetics for their gilts and boars but usually these sources differed. The average muscle depth recorded was 62 mm (SD=7.7) with a median of 62.5 mm and a farm level coefficient of variation of 12%. Compared to farms using multiple sources of genetics, using a specific source of gilts and a specific source of boars reduced the variation in the muscle depth.

Increasing hot carcass weight by 1 kg increased muscle depth by 0.34 mm. Producers raising the grower pigs in a continuous flow barn had a reduction in muscle depth (-70 mm) compared to producers who raised grower pigs in all in all out facilities (by barn, room or pen). Increasing the size of the sow herd by 50 sows, increased the muscle depth by .10 mm. However, farms with more boars had lower muscle depth. This may be a reflection of the positive effect of purchased semen used for AI.

Take Home Message

To increase muscle depth of carcasses, producers would be advised to

Use all in all out finisher facilities (by pen, room or barn)
Focus on using boars that have a high EBV for muscle depth

To reduce variation in fat depth in the pigs shipped from one farm

use a specific single source of gilt genetics and boar genetics known for muscle depth

We appreciate the support provided to us by the producers and packing plant who through their generosity gave of their time to complete surveys and shared their data. This study has received funding from the University of Guelph-OMAF animal research program.

Source: Animal & Poultry Science University of Guelph - Reproduced September 2005