98 research outputs found
Thermal Conditions Within Pens Fitted With Differing Zone-Heating Options and Resulting Performance of Newly Weaned Pigs in a Wean-to-Finish Facility
Research was conducted to assess the effects of the type of zone heater and floor mat used in a wean-to-finish building on the thermal environment created for newly weaned pigs and resulting pig performance. Gas-fired brooder heaters were compared to electric heat lamps and farm-cut wood sheathing was compared to commercial [unheated] rubber floor mats. No consistent differences in air temperature near the heating zone were found between either of the treatments. However, black-globe temperatures in pens having gas-fired heaters and/or wood mats were consistently warmer than in their comparison pens. Temperature deviations during the 26-day study period were similar statistically for both air and black-globe temperatures (about ±2.5°F) for all treatments, as were the temperature deviations from pen to pen for all treatment combinations (±1.7°F or less). Pig health was affected by an outbreak of porcine reproductive and respiratory syndrome (PRRSV). Performance of the disease-challenged pigs was similar for the two heating systems. However, pigs in pens having wood sheathing on the floor below the zone heater consumed more feed on a daily basis than those resting on rubber mats. This evidence supports statistically significant (P\u3c0.05) advantages for the wood mats in pig weight (+3%) and average daily gain (+6%) over the 26-day study period. Feed-to-gain ratios over this same time period were similar for all treatments. The fact that there was greater radiant heating (as indicated by warmer black-globe temperatures) with gas-fired heaters in this study suggests that extra adjustments in heater height and gas pressure may have been needed to obtain equivalent heating effects, and that additional information on placement and adjustment of zone heaters also would be useful to producers. The data collected in this study and associated experience of farm management imply that producers can develop an similarly stable thermal environment for nursery pigs using either electric heat lamps or gas-fired brooder heaters. The improved heating effect and pig performance observed in this study with floor mats made from wood sheathing have positive practical implications. Sheets of wood sheathing are readily available from many local lumber suppliers and hardware stores and can be purchased at a fraction of the price of commercial rubber mats. A small amount of labor is required to quarter the sheets, and we donât recommend re-using the wood mats. But, the results of this study suggest that wood sheathing should be investigated further as a floor-mat option
Assessment of Ventilation Management Training Workshops
To achieve optimum swine performance, producer understanding of environmental control systems in mechanically or naturally ventilated facilities is extremely important. A ventilation workshop: âManaging Your Unseen Employee: The Ventilation Systemâ was established. The primary objective of the training was to give swine producers and managers enough quality information so they could go back to their operations and properly assess their own ventilation systems and make appropriate adjustments as needed. The training workshops were established to be a multi-state and multi-disciplinary effort between South Dakota, Nebraska, Iowa and Minnesota universities. Ag engineers and animal scientists from each state participated in developing the workshop materials and delivery of the program. Four basic needs emerged that would enhance program delivery. These needs included basic environmental factors and their effects on pigs, ventilation system design principles, trouble-shooting ventilation problems, and hands-on demonstrations of instrumentation and ventilation equipment. A 1.8 m by 2.4 m by 2.4 m mobile ventilation room was used for the hands-on training. The mobile ventilation room was equipped with two variable-speed, 30-centimeter fans and one 30-cm, single-speed fan; a four-stage controller; and three types of air inlets. From 2002 to 2007, over 1000 people producing over 20 million pigs participated in more than 60 workshops. The backgrounds of participants included managers, feed consultants, extension educators, and veterinarians. Key points gained by producers included proper ventilation settings, trouble-shooting techniques, temperature control, and the effects of static pressure on airflow
Feedlot Surface Conditions and Ammonia Emissions
Moisture and urine were applied to a feedlot surface in a 2x2 factorial design. Forced-air wind tunnels were used to determine differences in the net flux of ammonia (NH3) being volatilized. Surface DM, pH and surface temperature were all analyzed within each treatment to determine effect on NH3 net flux. No effects of urine were detected. There were differences detected due to moisture and moisture*time with the dry plots releasing significantly more NH3
Feedlot Surface Conditions and Ammonia Emissions
Moisture and urine were applied to a feedlot surface in a 2x2 factorial design. Forced-air wind tunnels were used to determine differences in the net flux of ammonia (NH3) being volatilized. Surface DM, pH and surface temperature were all analyzed within each treatment to determine effect on NH3 net flux. No effects of urine were detected. There were differences detected due to moisture and moisture*time with the dry plots releasing significantly more NH3
Expression of Lewisâa glycans on polymorphonuclear leukocytes augments function by increasing transmigration
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141391/1/jlb0753.pd
Case Study: Producer concerns and perceptions regarding the effect of methane on cattle production and the environment: A survey of Nebraska producers
Enteric methane production from cattle and its effect on climate change has been a topic of debate. Multiple studies have explored methods to reduce cattle enteric methane production while simultaneously improving performance. However, most strategies developed have not been widely implemented by cattle producers. Knowledge of producer concerns and perceptions on methane production from cattle and its effect on the environment may be limited. Therefore, the objectives of this survey were to determine what Nebraska producers know about methane production by cattle and how it affects performance and to determine whether different age groups, regions of Nebraska, and production size and type affects producer opinions on enteric methane production and climate change. The survey had a response rate of 22%. Regarding climate change, approximately 39% of producers disagreed, 33% were neutral, and 28% agreed they were concerned. However, producers in central and eastern Nebraska were closer to neutral than producers in western Nebraska (P \u3c 0.05). Younger producers perceived cattle to have a more positive effect on the environment and reported that they were more likely to adopt new management techniques that have been shown to improve animal performance than older producers (P \u3c 0.05). Most producers reported receiving production-related information from veterinarians (47.6%), followed by the âotherâ category (34.9%), the University of Nebraska (15.6%), and state and federal governments, which were the lowest (1.4 and 0.6%, respectively). In the last 3 yr, approximately 57% of producers attended one or fewer extension meetings, but 37% had not attended any extension meetings
Case Study: Producer concerns and perceptions regarding the effect of methane on cattle production and the environment: A survey of Nebraska producers
Enteric methane production from cattle and its effect on climate change has been a topic of debate. Multiple studies have explored methods to reduce cattle enteric methane production while simultaneously improving performance. However, most strategies developed have not been widely implemented by cattle producers. Knowledge of producer concerns and perceptions on methane production from cattle and its effect on the environment may be limited. Therefore, the objectives of this survey were to determine what Nebraska producers know about methane production by cattle and how it affects performance and to determine whether different age groups, regions of Nebraska, and production size and type affects producer opinions on enteric methane production and climate change. The survey had a response rate of 22%. Regarding climate change, approximately 39% of producers disagreed, 33% were neutral, and 28% agreed they were concerned. However, producers in central and eastern Nebraska were closer to neutral than producers in western Nebraska (P \u3c 0.05). Younger producers perceived cattle to have a more positive effect on the environment and reported that they were more likely to adopt new management techniques that have been shown to improve animal performance than older producers (P \u3c 0.05). Most producers reported receiving production-related information from veterinarians (47.6%), followed by the âotherâ category (34.9%), the University of Nebraska (15.6%), and state and federal governments, which were the lowest (1.4 and 0.6%, respectively). In the last 3 yr, approximately 57% of producers attended one or fewer extension meetings, but 37% had not attended any extension meetings
Adiponectin reduces glomerular endothelial glycocalyx disruption and restores glomerular barrier function in a mouse model of type 2 diabetes
Adiponectin has vascular anti-inflammatory and protective effects. Although adiponectin protects against the development of albuminuria, historically, the focus has been on podocyte protection within the glomerular filtration barrier (GFB). The first barrier to albumin in the GFB is the endothelial glycocalyx (eGlx), a surface gel-like barrier covering glomerular endothelial cells (GEnCs). In diabetes, eGlx dysfunction occurs before podocyte damage; hence, we hypothesized that adiponectin could protect from eGlx damage to prevent early vascular damage in diabetic kidney disease (DKD). Globular adiponectin (gAd) activated AMPK signaling in human GEnCs through AdipoR1. It significantly reduced eGlx shedding and the TNF-αâmediated increase in syndecan-4 (SDC4) and MMP2 mRNA expression in GEnCs in vitro. It protected against increased TNF-α mRNA expression in glomeruli isolated from db/db mice and against expression of genes associated with glycocalyx shedding (namely, SDC4, MMP2, and MMP9). In addition, gAd protected against increased glomerular albumin permeability (Psâalb) in glomeruli isolated from db/db mice when administered intraperitoneally and when applied directly to glomeruli (ex vivo). Psâalb was inversely correlated with eGlx depth in vivo. In summary, adiponectin restored eGlx depth, which was correlated with improved glomerular barrier function, in diabetes
Patent Politics: Intellectual Property, the Railroad Industry, and the Problem of Monopoly
As winter descended on Washington in December 1878, the Forty-fifth Congress gathered for what promised to be a hectic third and final session. At this critical juncture in American politics, the Senate found itself embroiled in a long and complex discussion of the virtues and deficiencies of the patent system.
Patent policy resonated with powerfully felt ideologies and tapped into strongly felt beliefs. Patents were exclusive privileges that the federal government granted to certain individuals for a limited period of time, and, like all monopoly grants, their regulation raised some of the most fundamental questions of the age. The monopoly issue confronted every branch of nineteenth-century American government as well as every jurisdiction: federal, state, and local. In essence, the issue boiled down to two interrelated questions: Did the government have the authority to regulate the monopolies it had created? And, if so, how?
The ramifications of the patent issue were practical as well as ideological. At its core, it posed a special challenge for two groups of economic actors, namely, farmers and railroads, who were often at odds not only with Congress but also with each other
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