Technical Notes: Sampling Rate for Measurement of Piglet Thermoregulatory Behavior

Diurnal piglet behavior of heat lamp usage was recorded by photographic time lapse technique at 15 min intervals for 24 h and expressed as the percentage of litter mates using the heat lamp. The 15 min behavioral data was then divided into subsets with a sampling interval of 30, 45, 60, 75, 90, or 120 min; and data series comprised of the averages of 15 min data corresponding to each of the augmented sampling intervals. Correlation analyses between the subsets and the average data series indicated that a sampling interval of up to 60 min results in reliable measurement of the dynamic heat lamp usage of the piglets

A Study on the Air Flow and Odor Emission Rate from a Simplified Open Manure Storage Tank

This study presents a numerical evaluation of air flow and odor emission rate from an open manure storage tank. Odor emission rate is needed to facilitate the odor dispersion study and to compare different odor sources in terms of odor emission. The concentration at the manure surface, the tank dimensions, and wind speed were used to calculate air flow and the emission rate. The SIMPLER algorithm developed by Patankar (1980) and a two-layer turbulence model were used in the numerical simulation with a grid of 152 ¥ 139. The predicted emission rate agreed with the field measurement results found in the literature. Experimental verification of the air flow showed that the flow pattern and velocity profile prediction were also in agreement with the experimental results. The calculated odor-emission rate was a function of the manure surface area, the odor concentration at the manure surface, the tank dimensions, and the wind speed

Method and means for odor control in waste water lagoons

A method for controlling odor in a waste water lagoon comprises the steps of aerating a top horizontal layer of a lagoon adjacent its upper surface at a depth of approximately 12 to 24 inches by introducing air through a plurality of nozzles submerged in the layer to create a plurality of air bubbles in the layer. The nozzles are moved horizontally through the layer. A device for controlling the odor in waste water lagoons includes a support structure with an elongated boom operatively secured to the support structure and extending outwardly therefrom to operatively contact water in an adjacent lagoon. Compressed air is delivered through a plurality of downwardly extending nozzles on the boom into a layer of water on the top of the lagoon approximately 12 to 24 inches deep. Power elements are secured to the boom to cause the boom to move horizontally with respect to the lagoon while the compressed air is being delivered through the nozzles

Effects of Feeding Distillers Dried Grains with Solubles to Finishing Swine on Animal Performance, Manure Characteristics, and Odorous Emissions

Seventy-two finishing pigs were used to evaluate the effects of distillers dried grains with solubles (DDGS) on pig performance, manure characteristics, and odorous emissions. Three diets containing 0, 5, and 10% DDGS were fed during six 4-wk feeding periods. Week 1 served as a dietary adjustment period. Animals were housed in two feeding rooms (six pigs per room) with one treatment per room. A new group of animals (average initial Body Weight = 85.8 kg) was used for each feeding period. Diets were replicated four times. Rooms were equipped with individual shallow manure storage pits that were cleaned once weekly (day 7). On day 4 and 7 of each week manure pit samples and air samples in 10-liter Tedlar bags for olfactometry analysis were collected from each room. Dynamic dilution triangular forced-choice olfactometry was conducted using the Ac’scent International Olfactometer (St. Croix Sensory, Stillwater, MN) located in the Iowa State University Engineering Department of Agricultural and Biosystems. No differences in animal performance, as measured by average daily gain and feed efficiency, were observed (P \u3e .05). Greater feed disappearance (P \u3c .10) was observed from animals fed 10% DDGS. A nonsignificant trend of increasing odor, in terms of odor dilution threshold, was observed with increasing dietary concentration of DDGS (P = .16). A nonsignificant trend for increasing odor with increasing DDGS demonstrates the potential for diet formulation to improve odor. This increase in odor was likely due to the increased levels of dietary crude protein, amino acids, and elemental sulfur that were observed with increasing DDGS in the diets. Diet manipulation as a means to reduce odor needs to be investigated further