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Item Open Access Effects of ractopamine HCl dose and treatment period on pig performance in a commercial finishing facility(2013-04-24) Main, R.G.; Dritz, Steven S.; Tokach, Michael D.; Goodband, Robert D.; Nelssen, Jim L.; DeRouchey, Joel M.; dritz; mtokach; goodband; jnelssen; jderouchObjective: To evaluate effects of ractopamine HCl (RAC) dose and treatment period on growth performance and carcass composition in a commercial finishing environment. Materials and methods: In Experiment One, a total of 880 pigs (PIC L337 × C22; initially 106.5 ± 0.5 kg) were allotted to four treatments, including doses of 0, 5.0, 7.5, and 10.0 ppm of RAC for 21 days before slaughter. In Experiment Two, 1035 gilts (initially 103.2 ± 0.62 kg) were allotted to nine treatments. Treatments included doses of 5 or 10 ppm RAC for 7, 14, 21, or 28 days before slaughter and a control treatment without RAC. Results: In Experiment One, average daily gain (ADG), gain-to-feed ratio (G:F), and carcass yield increased (linear, P < .05) with increasing dose of RAC. The largest numeric differences were observed as RAC dose increased from 0 to 5 ppm. In Experiment Two, ADG and G:F were greater (P < .05) for pigs fed 5 ppm RAC for 14, 21, or 28 days and for pigs fed 10 ppm for all treatment periods than for control pigs. Carcass yield was greater in pigs fed 10 ppm RAC (P < .05) than in pigs fed 5 ppm RAC or in the controls. RAC dose (5 ppm versus 10 ppm) did not affect carcass lean measures (P > .16). Implications: Feeding RAC at 5 to 10 ppm for 14 to 28 days before slaughter increases ADG, G:F, and carcass yield of pigs reared in a commercial finishing environment.Item Open Access Effects of creep feeder design and feed accessibility on preweaning pig performance and the proportion of pigs consuming creep feed(2013-04-24) Sulabo, R.C.; Tokach, Michael D.; DeRouchey, Joel M.; Dritz, Steven S.; Goodband, Robert D.; Nelssen, Jim L.; mtokach; jderouch; dritz; goodband; jnelssenObjective: To determine the effects of creep feeder design and feed accessibility on preweaning performance and the proportion of eaters of creep feed. Materials and methods: A total of 54 sows and their litters were assigned to three treatments: rotary feeder with hopper, rotary feeder without hopper, and pan feeder. A creep diet with 1.0% chromic oxide was offered ad libitum from Day 18 until weaning (Day 21). Fecal samples were collected from piglets with sterile swabs 3 to 12 hours before weaning. Piglets were categorized as “eaters” when either of the two fecal samples was colored green; otherwise, they were categorized as “non-eaters.” Pigs were weighed Days 0 (birth), 18, and 21, and litter creep-feed disappearance was determined daily. Results: There were no differences (P > .05) in preweaning gains and weaning weights of pigs and litters using the different types of creep feeder. Litters provided creep feed using the rotary feeder with the hopper had 2.7 times lower total creep-feed disappearance than litters using the rotary feeder without the hopper and the pan feeder (P < .001). However, the rotary feeder with the hopper produced the highest proportion of pigs consuming creep feed within the litter (80%; P < .001). Implications: The proper choice of creep feeder is essential to manage creep feeding and to maximize the number of eaters in the litter. A creep feeder with a hopper may create more eaters with less feed wastage.Item Open Access Feed additives for swine: Fact sheets – prebiotics and probiotics, and phytogenics(2013-04-24) Jacela, J.Y.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Nelssen, Jim L.; Renter, David G.; Dritz, Steven S.; jderouch; mtokach; goodband; jnelssen; drenter; dritzThere is increasing pressure for livestock producers to minimize the use of antibiotics as growth promoters in food animals. Supplementing beneficial microorganisms in the gastrointestinal tract is one potential alternative. A diverse population of beneficial and potentially harmful microorganisms exists in the gastrointestinal tract of the pig. In a healthy animal, a delicate balance between these two groups of organisms is maintained. However, during times of stress, such as during weaning in the case of piglets, this balance may be affected and can lead to a rapid growth of harmful microorganisms. This may result in poor performance or disease. Thus, prebiotics and probiotics have been the subject of much research over the years as potential replacements for antibiotic growth promoters in pigs.Item Open Access Feed additives for swine: Fact sheets – high dietary levels of copper and zinc for young pigs, and phytase(2013-04-24) Jacela, J.Y.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Nelssen, Jim L.; Renter, David G.; Dritz, Steven S.; jderouch; mtokach; goodband; jnelssen; dritz; drenterCopper and zinc play important roles in many physiological processes. Dietary copper levels of 5 to 10 ppm and zinc levels of 50 to 125 ppm are generally enough to meet the pig’s nutrient requirement for these processes. However, when supplied at high concentrations (100 to 250 ppm for copper and 2000 to 3000 ppm for zinc), these two minerals are known to exert positive influences on growth rate. In addition, copper is efficacious even when antibiotics also are included in the diets.2 This suggests that the response to copper is additive to the response to antimicrobials. Response to high levels of dietary copper decreases with increasing age and with longer periods of administration.3 Zinc fed at high dietary levels (2000 to 3000 ppm) reduces incidence of diarrhea and increases weight gain in newly weaned pigs. However, these high levels of dietary zinc are beneficial to pigs only during the early phases of the nursery period.6 Thus, feeding period for high dietary levels of zinc should be limited to approximately 3 weeks after weaning. Additive effects are usually not observed in weaned pigs when high levels of copper and zinc are added together. However, the data is conflicting and this observation needs to be further investigated. Recent research has indicated that feeding high levels of zinc until pigs reached 12 kg, then feeding high levels of copper for the remainder of the nursery period, was the most cost-effective strategy.Item Open Access Feed additives for swine: Fact sheets – flavors and mold inhibitors, mycotoxin binders, and antioxidants(2013-04-24) Jacela, J.Y.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Nelssen, Jim L.; Renter, David G.; Dritz, Steven S.; jderouch; mtokach; goodband; jnelssen; drenter; dritzUnder the conditions of modern swine production, pigs need to be fed a balanced diet that meets their daily nutritional requirement for maintenance, growth, and reproduction. However, nutrient intake is largely determined by voluntary feed intake, which is greatly influenced by the chemical senses of olfaction and taste. Thus, it is essential to make sure that diets being offered to pigs are highly palatable to ensure high feed intake. This is especially important during times when pigs have decreased appetite, such as the first few days post weaning. Therefore, it is believed that enhancement of taste or smell through the use of flavors may help to improve the palatability of diets and, consequently, feed intake.Item Open Access Feed additives for swine: Fact sheets – carcass modifiers, carbohydrate-degrading enzymes and proteases, and anthelmintics(2013-04-24) Jacela, J.Y.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Nelssen, Jim L.; Renter, David G.; Dritz, Steven S.; jderouch; mtokach; goodband; jnelssen; drenter; dritzThere is increasing consumer demand for leaner and healthier pork products. Improvements in genetics, new technologies, and increased understanding of nutrition have become instrumental in helping producers meet this demand. Continued research also has led to the development of products that can be included in swine diets as carcass modifiers. A dietary carcass modifier is broadly defined as any component of the diet that alters the resulting carcass composition of pigs. Generally, the mechanism of action of carcass modifiers is aimed at increasing protein and muscle deposition while reducing fat deposition. These products vary in the mechanisms by which they modify carcass quality. In addition, not all carcass modifiers are approved for use in pig diets, for public-health reasons. Understanding the modes of action and differences between these products is important for safe and effective use.Item Open Access Feed additives for swine: Fact sheets – acidifiers and antibiotics(2013-04-24) Jacela, J.Y.; DeRouchey, Joel M.; Tokach, Michael D.; Goodband, Robert D.; Nelssen, Jim L.; Renter, David G.; Dritz, Steven S.; jderouch; mtokach; goodband; jnelssen; dritz; drenterFeed additives are non-nutritive products used in swine diets to improve production efficiency and performance. If chosen carefully and used properly, feed additives can be effective and can help increase the profi tability of pig production. Not all feed additives are the same or provide a benefi cial response and, therefore, choosing a product will depend on the farm’s specific situation and needs. This series of fact sheets includes some of the major classifications of products used as feed additives. Every effort has been made to ensure that all the information in every fact sheet is current and based on the latest scientific publications available at the time of writing. The objective of these fact sheets is to discuss some of the basic concepts to help producers improve their understanding of these products. They also aim to promote more responsible and judicious use of feed additives. Feed-additive products used in swine diets include natural and synthetic substances and have been grouped in this series of fact sheets according to the classifications shown in the text box. Each group of feed additives is discussed in a separate fact sheet, with special emphasis on some of the common questions that producers might have for each product. Feed additives offer a variety of potential benefits. However, they add to total production cost and should be evaluated carefully. Because their use in pig diets is to improve performance and profitability, an effective feed-additive product must be able to pay for itself. It must be able to provide an improvement in productivity that is, at minimum, equivalent to the added cost of the feed-additive product. This highlights the value of scientifi c data from well-designed experiments as the basis for evaluating such products. Having access to such information is critical in determining if one product’s claims are actually possible and repeatable in commercial settings. Producers must always try to verify that the data for a particular product came from controlled, unbiased experiments with supporting statistical data. When choosing between feed-additive products, priority for using a specific product should be given to those that have been shown to provide consistent results in research trials.Item Open Access Determining the accuracy of gestation feed drops(2012-04-06) Schneider, J.D.; Tokach, Michael D.; Dritz, Steven S.; Nelssen, Jim L.; DeRouchey, Joel M.; Goodband, Robert D.; mtokach; dritz; jnelssen; jderouch; goodbandSummary Objective: To determine the accuracy of three different types of gestation feed drops. Materials and methods: Econo, Accu, and Ultra feed drops (Automated Production Systems, Assumption, Illinois) were attached to feed lines at three angles (90˚, 75˚, and 60˚). Feed was collected and weighed at settings of 2, 4, 6, 8, and 10 lb (0.9, 1.8, 2.7, 3.6, and 4.65 kg) for the Econo and Accu feed drops and 2, 4, 6, and 8 lb for the Ultra feed drops. Results: There was a drop type × angle × feed level interaction (P < .01) for the feed settings versus the actual amount dropped. At 90˚, the relationship between the feeder setting (x) and actual quantity of feed dropped was best described by the regression equation (1.156x + 0.244) for the Econo, (1.010x + 0.072) for the Accu, and (1.009x + 0.231) for the Ultra feed drops. At 75˚, the regression equations were (1.014x – 0.139) for the Econo, (0.997x + 0.057) for the Accu, and (1.005x + 0.156) for the Ultra feed drops. At 60˚, the regression equations were (0.689x – 0.076) for the Econo, (0.989x – 0.249) for the Accu, and (0.951x + 0.026) for the Ultra feed drops. Implications: The type of feed drop and its angle relative to the feed line influences the amount of feed dispensed at a feeder setting. The Accu and Ultra feed drops more accurately dispense the correct amount of feed than the Econo feed drops.
