11 research outputs found
Analysis of feeding behavior of group housed growingâfinishing pigs
Feeding behavior and time spent eating contains valuable information that can be used for managing livestock, identifying sick animals, and determining genetic differences within a herd. Individual animal feeding behavior, in a commercial-sized pen, was recorded using radio-frequency identification (RFID) technology and a series of multiplexers. Data were collected on 960 pigs (mixed barrows, 406 and gilts, 600) over 4 grow-out periods. The animals entered the facility at 24.6 ± 5.4 kg (mean ± standard deviation) at approximately 65 days of age and exited the facility at 101.4 ± 13.8 kg (between 116 and 133 days later). Time spent at the feeder was analyzed for the effects of days on feed, sex, weight gain, and health effects. The amount of time spent at the feeder averaged 68.8 min dayâ1 pigâ1 over the grow-out period, and increased from the day the pigs enter the facility (24.0 ± 1.6 min dayâ1 pigâ1; mean ± standard error) until plateauing at approximately 40 days later (76.7 ± 2.4 min dayâ1 pigâ1; age ~ 105 days). After the plateau, barrows spent 13.6 more minutes per day at the feeder than gilts. Pigs classified as âhigh gainingâ (79.2 ± 5.1 min dayâ1 pigâ1) spent more time at the feeder than pigs classified as either ânormalâ (72.6 ± 2.6 min day-1 pigâ1) or âlow gainingâ (67.6 ± 5.3 min dayâ1 pigâ1). This initial manuscript demonstrates the potential of utilizing feeding behavior or time spent eating as a method of managing animals
NUTRIENT TRANSPORT IN RUNOFF AS AFFECTED BY DIET, TILLAGE, AND MANURE APPLICATION RATE
Feedlot operators may increase profitability by including distillers grains in finishing diets. However, the nutrients remaining in the byâproduct are concentrated by about a factor of three during the distillation process. Manure can be applied to meet singleâ or multipleâyear crop nutrient requirements. The water quality effects of the use of distillers grains in feedlot diets and multipleâyear manure application have not been well quantified. The objectives of this study were to (1) compare the runoff water quality effects resulting from the application of manure derived from corn and distillers grain diets, (2) examine the effects of till and noâtill conditions on runoff nutrient transport, and (3) compare the water quality impacts of 1â, 2â, and 4âyear phosphorus (P) based manure application rates. Simulated rainfall events were applied to 0.75 m wide Ă 2 m long plots soon after manure application. No significant difference in dissolved phosphorus (DP) or total P (TP) load was found between the corn and distillers grain treatments. The runoff load of TP was significantly larger on the noâtill plots than on the till plots. The amount of particulate phosphorus (PP), DP, and TP transported in runoff was significantly affected by multiâyear application of manure. The TN content of runoff was similar for till and noâtill conditions on the plots containing manure obtained from the distillers grain diet. The environmental effects of the use of manure from a distillers grain diet and multipleâyear manure application should be considered when developing nutrient management plans