165 research outputs found

    Climate Dependent Heat Stress Mitigation Modeling for Dairy Cattle Housing

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    Dairy cattle are susceptible to heat stress with reported milk production loss exceeding 1.2 billion dollars in 2010. Heat stress occurs when the local thermal environment prevents adequate dissipation of metabolic heat production over extended periods. Implementing mitigation strategies in order to reduce heat stress has been a crucial need as dairy housing has transitioned from pasture to indoor housing systems. In order to maximize production, producers need the most effective cooling system to reduce heat stress. A heat stress mitigation model was developed using TMY3 data sets as inputs. The objectives of this research were to: (i) analyze the thermal environment’s ability to reduce heat stress in dairy cattle in selected regions using TMY3 data, (ii) model Holstein cattle subjected to various environmental modification systems (elevated airspeed, evaporative pad cooling, direct sprinkling) by region, (iii) create a universal barn/cooling system model to apply to selected regions with given TMY3 data inputs, and (iv) develop contour maps with optimal cooling system recommendations throughout the United States. A transient thermal balance model was developed using equations and parameters from published heat stress models in order to quantify heat dissipation from a dairy cow to her environment. The model was initially tested and evaluated using two TMY3 stations (Fresno, California SN:723890 and Eau Claire, Wisconsin SN:726435). The model’s predictions were within one standard deviation of field data. Once validated, the model was applied to all 215 TMY3 Class 1 stations and contour maps of the U.S. were created for producers to determine which cooling strategy is the most economical in their region

    Heavy-Duty Stoichiometric Compression Ignition Engine with Improved Fuel Economy over Alternative Technologies for Meeting 2010 On-Highway Emission

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    The objectives of the reported work were: to apply the stoichiometric compression ignition (SCI) concept to a 9.0 liter diesel engine; to obtain engine-out NO{sub x} and PM exhaust emissions so that the engine can meet 2010 on-highway emission standards by applying a three-way catalyst for NO{sub x} control and a particulate filter for PM control; and to simulate an optimize the engine and air system to approach 50% thermal efficiency using variable valve actuation and electric turbo compounding. The work demonstrated that an advanced diesel engine can be operated at stoichiometric conditions with reasonable particulate and NOx emissions at full power and peak torque conditions; calculated that the SCI engine will operate at 42% brake thermal efficiency without advanced hardware, turbocompounding, or waste heat recovery; and determined that EGR is not necessary for this advanced concept engine, and this greatly simplifies the concept

    Disruption of female reproductive function by endotoxins

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    Endotoxemia can be caused by obesity, environmental chemical exposure, abiotic stressors, and bacterial infection. Circumstances that deleteriously impact intestinal barrier integrity can induce endotoxemia and controlled experiments have identified negative impacts of lipopolysaccharide (LPS; an endotoxin mimetic) on folliculogenesis, puberty onset, estrus behavior, ovulation, meiotic competence, luteal function and ovarian steroidogenesis. In addition, neonatal LPS exposures have transgenerational female reproductive impacts, raising concern about early life contacts to this endogenous reproductive toxicant. Aims of this review are to identify physiological stressors causing endotoxemia, to highlight potential mechanism(s) by which LPS compromises female reproduction, and identify knowledge gaps regarding how acute and/or metabolic endotoxemia influence(s) female reproduction

    A supplement containing multiple types of gluconeogenic substrates alters intake but not productivity of heat-stressed Afshari lambs

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    Citation: Mahjoubi, E., Amanlou, H., Yazdi, M. H., Aghaziarati, N., Noori, G. R., Vahl, C. I., . . . Baumgard, L. H. (2016). A supplement containing multiple types of gluconeogenic substrates alters intake but not productivity of heat-stressed Afshari lambs. Journal of Animal Science, 94(6), 2497-2505. doi:10.2527/jas2015-9697Thirty-two Afshari lambs were used in a completely randomized design with a 2 x 2 factorial arrangement of treatments to evaluate a nutritional supplement designed to provide multiple gluconeogenic precursors during heat stress (HS). Lambs were housed in thermal neutral (TN) conditions and fed ad libitum for 8 d to obtain covariate data (period 1 [P1]) for the subsequent experimental period (period 2 [P2]). During P2, which lasted 9 d, half of the lambs were subjected to HS and the other 16 lambs were maintained in TN conditions but pair fed (PFTN) to the HS lambs. Half of the lambs in each thermal regime were fed (top-dressed) 100 g/d of a feed supplement designed to provide gluconeogenic precursors (8 lambs in HS [heat stress with Glukosa {HSG}] and 8 lambs in PFTN [pair-fed thermal neutral with Glukosa]) and the other lambs in both thermal regimes were fed only the basal control diet (HS without Glukosa [HSC] and pair-fed thermal neutral without Glukosa). Heat stress decreased DMI (14%) and by design there were no differences between the thermal treatments, but HSG lambs had increased DMI (7.5%; P < 0.05) compared with the HSC lambs. Compared with PFTN lambs, rectal temperature and skin temperature at the rump, shoulder, and legs of HS lambs were increased (P < 0.05) at 0700 and 1400 h. Rectal temperature at 1400 h decreased for HSG lambs (0.15 +/- 0.03 degrees C; P < 0.05) compared with HSC lambs. Despite similar DMI between thermal treatments, ADG for HS and PFTN lambs in P2 was decreased 55 and 85%, respectively, compared with lambs in P1 (P < 0.01). Although the prefeeding glucose concentration was not affected by thermal treatment or diet, HSG lambs had increased postfeeding glucose concentration compared with HSC lambs (P < 0.05). In contrast to the glucose responses, circulating insulin was influenced only by thermal treatment; HS lambs had increased insulin concentration (P < 0.01) before feeding and decreased concentration (P < 0.05) after feeding compared with PFTN lambs. Heat-stressed lambs had decreased NEFA concentration before feeding (P < 0.01) but not after feeding relative to PFTN lambs. Although this nutritional strategy did not affect ADG, the lower rectal temperature in HSG lambs indicates that dietary inclusion of a mixture of glucogenic precursors can potentially benefit animal health during HS

    Methods for reproductive tract scoring as a tool for improving sow productivity

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    Improving sow lifetime productivity (SLP) is essential for maximizing farm profitability. Study objectives were to determine the accuracy for different vulva scoring methods in a commercial production system and to assess whether gilt reproductive tract scoring (evaluated by vulva width; VW) prior to puberty could serve as useful gilt selection criteria. To accomplish this objective, 958 prepubertal replacement gilts in a commercial system were evaluated at approximately 15 weeks of age. Gilt body weight was recorded in addition to four different methods to evaluate VW. Methods for VW assessment included digital caliper measurement (mm), visual evaluation and scoring by trained farm personnel (Farm Score; FS), and two methods using scoring tools (Vulva Score Method A and B; VSA and VSB, respectively) specifically calibrated from the VW distribution measured on gilts from previous studies. The VSA and FS methods assigned gilts to one of three categories (S, M, L and 1, 2, 3, respectively) whereas VSB classified gilts vulvas using a five-point scoring system (1 to 5). At 15-wk of age, a low proportion of variability in vulva size (27.8 ± 0.1 mm) could be explained by BW (62.2 ± 0.2 kg; R2 = 0.05). All three scoring methods were effective in categorizing gilts based upon VW, as the measured VW size within methods differed by score (P \u3c 0.01). The proportion of gilts achieving their first parity increased with score for VSA (64.7, 73.2, and 84.4%; P = 0.02), VSB (66.0, 71.7, 79.2, 76.4, and 84.2%; P = 0.02), and FS (67.2, 75.0, and 88.8%; P = 0.03), but VSA, VSB, and FS did not influence percentage of gilts achieving their second parity (P = 0.32, 0.29, and 0.30, respectively). Litter performance of gilts scored as M or L using VSA improved with an increased total born over two parities compared to those scored as S (23.96 vs. 26.38 pigs; P \u3c 0.01) as well as born alive (21.13 vs. 23.05 pigs; P \u3c 0.05). Results were similar for VSB, where scores 2-5 had greater total born (23.97 vs. 26.33 pigs; P \u3c 0.01) and born alive (21.11 vs. 23.02 pigs; P \u3c 0.05) through two parities compared to gilts scored 1. Using the FS method, total born pigs tended to be increased (P = 0.06) through two parities for gilts having a 2 or 3 vulva score compared to those scored as a 1. Collectively, assessing VW at approximately 15 wk of age may identify sows with improved productivity through two parities as breeding herd females

    Leaky Gut’s Contribution to Inefficient Nutrient Utilization

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    There are a variety of situations in an animal’s life when nutrient utilization is reprioritized from productive towards agriculturally unproductive purposes. Two well-known examples that markedly reduce production are heat stress and ketosis. Decreased feed intake, experienced during both disorders, is unable to fully explain production losses. Additionally, both disorders are characterized by negative energy balance, body weight loss, inflammation, and liver fat accumulation. While the metabolism of ketosis and heat stress has been thoroughly studied for the last 40 years, the initial insult in the cascade of events ultimately reducing productivity in both heat-stressed and ketotic cows has not been identified. To that end, we have generated preliminary data strongly implicating a metabolic disruptor, endotoxin, as the underlying cause in each case

    Ornamental plants: a summary of research, 1993-1994

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    Aesthetic evaluation of crabapples at the Secrest Arboretum in Wooster, Ohio: 1993-1994 / Erik A. Draper and James A. Chatfield -- Evaluation of crabapples for apple scab at the Secrest Arboretum in Wooster, Ohio: 1993-1994 / James A. Chatfield and Erik A. Draper -- The Ohio State University Water Quality Assessment Program / Mary Ann Rose, John Peterson and Laura Kramer -- Root rot of Taxus spp in Ohio caused by Phytophthora cinnamomi / Michael A. Ellis, Sally A. Miller, August F. Schmitthenner and Kenneth D. Cochran -- Winter injury on woody ornamental plants in Ohio: the winter of 1993-1994 / T. Davis Sydnor, James A. Chatfield, Randall H. Zondag, Pamela J. Bennett, Joseph F. Boggs, Kenneth D. Cochran -- Ornamental plant problems in Ohio: 1994 / James A. Chatfield, David J. Shetlar, Nancy Taylor, Joseph F. Boggs, Pamela J. Bennett, Randall H. Zondag, Michael A. Ellis, Allen Baumgard -- Ornamental plant problems in Ohio: 1993 / James A. Chatfield, Joseph F. Boggs, Paul Kauffman, David J. Shetlar, Nancy Taylor, Randall H. Zonda

    Ornamental plants: annual reports and research summaries

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    The Ohio State University Extension Nursery, Landscape, and Turf Team (ENLTT) -- Extension Nursery, Landscape, and Turf Team (ENLTT) directory -- An evaluation of composts for landscape soil amendments / Mary Ann Rose and Hao Wang -- Aesthetic evaluation of crabapples at Secrest Arboretum in Wooster, Ohio: 1994-1995 / James A. Chatfield, Erik A. Draper, Kenneth C. Cochran, Peter W. Bristol and Charles E. Tubesing -- Evaluation of crabapples for apple scab at Secrest Arboretum in Wooster, Ohio: 1995 / Erik A. Draper, James A. Chatfield, Kenneth C. Cochran, Peter W. Bristol and Charles E. Tubesing -- Emergence, longevity, and aesthetic evaluations of flowers in ornamental crabapples at Secrest Arboretum in Wooster, Ohio: 1995 / Erik A. Draper, James A. Chatfield and Kenneth C. Cochran -- Environmental and cultural ornamental plant problems in Ohio: 1995 / Pamela J. Bennett and Jane A. Martin -- 1995 -A Challenging Year for Ohio golf courses / Joseph W. Rimelspach, John R. Street, Karl Danneberger, William E. Pound, Barbara Bloetscher -- Plant insect pest problems in Ohio: 1995 / Joseph F. Boggs, David J. Shetlar, Gary Yu Gao, Daniel Balser, Douglas C. Caldwell, Randall H. Zondag and James A. Chatfield -- Gypsy moth in Ohio: 1995 / Allan Baumgard, David F. James and Randall H. Zondag -- Landscape ornamental disease problems in Ohio: 1995 / James A. Chatfield, Nancy Taylor, Randall H. Zondag, Mary Ann Rose, Gary Yu Gao, Daniel R. Balser and David J. Shetlar -- The Response of native and naturalized trees to construction activity / T. Davis Sydnor, Joseph F. Boggs and Mary Ann Ros
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