Loin depth is one of the key characteristics that pork producers strive to increase because they are paid a premium for pigs with larger loins. So why has the average loin depth across the province dropped dramatically since the first quarter of 2005?
It’s a complicated issue, but perhaps the most likely culprit is disease.
Ontario pork producers have been battling several serious diseases over the past few years, including PRRS and circovirus. While the most obvious effects have been on increased mortality and morbidity rates and an increase in medication costs, the higher incidence of disease may also be having an effect on carcass characteristics.
Chris Hills works for Wallenstein Feed and Supply Ltd. He helps his customers analyze market hog data using Ontario Pork’s Online Information Network Knowledgebase (OINK). He often looks at the data and suggests to producers how marketing might be done differently to help them take advantage of premiums offered by the packers.
One of his clients came to him with a concern that the loin eye area of his hogs seemed to be decreasing steadily over time. Loin eye is a measurement of the meat in a pig’s back that makes up the pork chop and one of the key factors that those in the industry strive to maximize.
Hills took a look and discovered that the loin eye area of his producer’s stock was indeed declining. There had been eight turns through this particular barn over the span of about three years that seemed to show a steady decline. The market weight of the animals was not significantly different, but the average loin eye size had dropped from a high of 64.7 millimetres to 57.6 millimetres on the last group. “That’s huge!” says Hills.
The producer had changed genetics, but had switched to a line about three years ago which should have improved carcass quality. Hills contacted the genetics supplier and got recommendations for feed, but it has not made a difference. The producer has several other barns that are not using Wallenstein feed and they are all experiencing the same drop in loin eye area.
Hills was curious and raised the question among colleagues in the industry. He discovered that his producer was not alone and that data from Ontario Pork revealed that there had been a steady decline in loin eye area for all pigs marketed across Ontario since the first quarter of 2005.
In the same quarter of 2000, the average loin depth of pigs marketed in Ontario was 56.61 millimetres. It has increased every quarter until the first quarter of 2005, to a high of 63.17 millimetres, at which point it started to fall and has dropped each quarter since then to a low of 60.26 in 2006 (see chart 1). This is significant because it is not about one producer or one month. It is a measurement of all the pigs marketed in the province over the span of many months.