Larry D. Jacobson University of Minnesota

Resources Authored

Factsheets

Heat Exchangers in Swine Facilities

Publish Date: 04/04/2012

Ventilation air-to-air heat exchangers are used in swine housing facilities to reduce supplemental heating cost and to preheat incoming fresh air. There is potential for heat exchanger use in some swine barns, since as much as 90% of the total heat loss from an insulated swine nursery facility occurs through the minimum ventilation air exchange. Heat exchangers recover a portion of this loss, depending upon design and maintenance. In addition to reducing fuel use, heat exchangers preheat the incoming ventilation air thereby reducing the potential for drafts on piglets and reducing frosting problems when air enters directly from outside. Heat exchangers also improve air distribution, because warmed inlet air will not drop as rapidly as cold inlet air.


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Resources Reviewed

Factsheets

Science of Smell Part 3 : Measurement and Detection of Odors from Swine Operations

Publish Date: 11/27/2012

As perceived by humans, odors have five basic properties that can be quantified: 1) intensity, 2) degree of offensiveness, 3) character, 4) frequency, and 5) duration, all of which contribute to the neighbor’s attitude towards the odor as well as the pig production generating the odor. It is generally accepted that the extent of objection and reaction to odor by neighbors is highly variable. The reaction can be based on previous experience, relationship to the odor-producing enterprise and the sensitivity of the individual. Weather (temperature, humidity, wind direction) affects the volatility of compounds, preventing or enhancing movement into the gaseous phase where an odor can be dispersed downwind.


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Factsheets

Science of Smell Part 1 : Perception and Physiological Responses to Odors

Publish Date: 11/27/2012

Olfaction, the sense of smell, is the least understood of the five human senses. This, among other factors, makes the task of reducing livestock odors a considerable challenge. This factsheet explains the terminology used to describe odorants and odor, how the human olfactory system works, and how humans respond to odor.


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Factsheets

Seasonality of hog prices

Publish Date: 08/23/2006

Hog prices historically have shown variation from month to month with a tendency for the changes to follow a degree of seasonal regularity from year to year. Because the changes during the year are repetitive or consistent, they are a useful input into production, marketing, or pricing decisions. Seasonal price changes result from changes in the supply of hogs and pork, changes in consumer demand for pork products, or a combination of these factors. Seasonal variations in pork supply are less pronounced now than they were 15 to 20 years ago. With more of the production coming from larger operations, sow farrowings are more evenly distributed throughout the year; however, there is still enough month-tomonth variation in farrowings to bring significant seasonal changes in levels of pork production. Consumer demand for pork and for particular retail cuts and products also varies somewhat from one period of the year to another.


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Factsheets

Shallow Gutter Manure Collection Systems

Publish Date: 06/03/2006

Research has shown and field experience has verified that corrosive and odorous gas production increases with storage time and storage temperature. Manure can be removed from a swine barn by: (1) manual or mechanical scraping, (2) gravity draining, (3) flushing with dump tanks, siphons or pumping systems with automatic or manually controlled valves, or (4)…


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