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Author Bernabucci, U.; Biffani, S.; Buggiotti, L.; Vitali, A.; Lacetera, N.; Nardone, A. doi  openurl
  Title The effects of heat stress in Italian Holstein dairy cattle Type Journal Article
  Year 2014 Publication Journal of Dairy Science Abbreviated Journal J. Dairy Sci.  
  Volume 97 Issue 1 Pages 471-486  
  Keywords Animals; Breeding; Cattle; Dietary Fats/analysis; Dietary Proteins/analysis; Female; Genetic Variation; Heat Stress Disorders/*veterinary; *Hot Temperature; Humans; Humidity; *Lactation; Linear Models; Milk/chemistry; Parity; Phenotype; Weather; dairy cow; heritability; production trait; temperature-humidity index breaking point  
  Abstract The data set for this study comprised 1,488,474 test-day records for milk, fat, and protein yields and fat and protein percentages from 191,012 first-, second-, and third-parity Holstein cows from 484 farms. Data were collected from 2001 through 2007 and merged with meteorological data from 35 weather stations. A linear model (M1) was used to estimate the effects of the temperature-humidity index (THI) on production traits. Least squares means from M1 were used to detect the THI thresholds for milk production in all parities by using a 2-phase linear regression procedure (M2). A multiple-trait repeatability test-model (M3) was used to estimate variance components for all traits and a dummy regression variable (t) was defined to estimate the production decline caused by heat stress. Additionally, the estimated variance components and M3 were used to estimate traditional and heat-tolerance breeding values (estimated breeding values, EBV) for milk yield and protein percentages at parity 1. An analysis of data (M2) indicated that the daily THI at which milk production started to decline for the 3 parities and traits ranged from 65 to 76. These THI values can be achieved with different temperature/humidity combinations with a range of temperatures from 21 to 36°C and relative humidity values from 5 to 95%. The highest negative effect of THI was observed 4 d before test day over the 3 parities for all traits. The negative effect of THI on production traits indicates that first-parity cows are less sensitive to heat stress than multiparous cows. Over the parities, the general additive genetic variance decreased for protein content and increased for milk yield and fat and protein yield. Additive genetic variance for heat tolerance showed an increase from the first to third parity for milk, protein, and fat yield, and for protein percentage. Genetic correlations between general and heat stress effects were all unfavorable (from -0.24 to -0.56). Three EBV per trait were calculated for each cow and bull (traditional EBV, traditional EBV estimated with the inclusion of THI covariate effect, and heat tolerance EBV) and the rankings of EBV for 283 bulls born after 1985 with at least 50 daughters were compared. When THI was included in the model, the ranking for 17 and 32 bulls changed for milk yield and protein percentage, respectively. The heat tolerance genetic component is not negligible, suggesting that heat tolerance selection should be included in the selection objectives.  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1525-3198 (Electronic) 0022-0302 (Linking) ISBN Medium Article  
  Area Expedition Conference  
  Notes (up) LiveM, ft_macsur Approved no  
  Call Number MA @ admin @ Serial 4617  
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Author Shrestha, S.; Hennessy, T.; Abdalla, M.; Forristal, D.; Jones, M.J. url  openurl
  Title Determining short term responses of Irish dairy farms under climate change Type Journal Article
  Year 2014 Publication German Journal of Agricultural Economics Abbreviated Journal German Journal of Agricultural Economics  
  Volume 63 Issue 3 Pages 143-155  
  Keywords  
  Abstract This study aimed to determine short term farm responses of Irish dairy farms under climate change. The Irish National Farm Survey data and Irish weather data were the main datasets used in this study. A set of simulation models were used to determine grass yields and field time under a baseline scenario and a future climate scenario. An optimising farm level model which maximises farm net income under limiting farm resources was then run under these scenarios. Changes in farm net incomes under the climate change scenario compared to the baseline scenario were taken as a measure to determine the effect of climate change on farms. Any changes in farm activities under the climate run compared to the baseline run were considered as farm’s responses to maximise farm profits. The results showed that there was a substantial increase in yields of grass (49% to 56%) in all regions. The impact of climate change on farms was different based on the regions. Dairy farms in the Border, Midlands and South East regions suffered whereas dairy farms in other regions generally fared better under the climate change scenario. For a majority of farms, a substitution of concentrate feed with grass based feeds and increasing stocking rate were identified as the most common farm responses. However, farms replaced concentrate feed at varying degree. Dairy farms in the Mid East showed a move towards beef production system where medium dairy farms in the South East regions shifted entire tillage land to grass land. Farms in the South East region also kept animals on grass longer under the climate change scenario compared to the baseline scenario.  
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  Language English Summary Language Original Title  
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  Area Expedition Conference  
  Notes (up) TradeM Approved no  
  Call Number MA @ admin @ Serial 4672  
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Author Eory, V.; MacLeod, M.; Shrestha, S.; Roberts, D. url  openurl
  Title Linking an economic and a life-cycle analysis biophysical model to support agricultural greenhouse gas mitigation policy Type Journal Article
  Year 2014 Publication German Journal of Agricultural Economics Abbreviated Journal German Journal of Agricultural Economics  
  Volume 63 Issue Pages 133-142  
  Keywords  
  Abstract Greenhouse gas (GHG) mitigation is one of the main challenges facing agriculture, exacerbated by the increasing demand for food, in particular for livestock products. Production expansion needs to be accompanied by reductions in the GHG emission intensity of agricultural products, if significant increases in emissions are to be avoided. Suggested farm management changes often have systemic effects on farm, therefore their investigation requires a whole farm approach. At the same time, changes in GHG emissions arising offfarm in food supply chains (pre- or post-farm) can also occur as a consequence of these management changes. A modelling framework that quantifies the whole-farm, life-cycle effects of GHG mitigation measures on emissions and farm finances has been developed. It is demonstrated via a case study of sexed semen on Scottish dairy farms. The results show that using sexed semen on dairy farms might be a costeffective way to reduce emissions from cattle production by increasing the amount of lower emission intensity ‘dairy beef’ produced. It is concluded that a modelling framework combining a GHG life cycle analysis model and an economic model is a useful tool to help designing targeted agri-environmental policies at regional and national levels. It has the flexibility to model a wide variety of farm types, locations and management changes, and the LCA-approach adopted helps to ensure that GHG emission leakage does not occur in the supply chain.  
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  Language English Summary Language Original Title  
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  Area Expedition Conference  
  Notes (up) TradeM Approved no  
  Call Number MA @ admin @ Serial 4670  
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Author Bourgeois, C.; Fradj, N.B.; Jayet, P.-A. url  doi
openurl 
  Title How cost-effective is a mixed policy targeting the management of three agricultural N-pollutants Type Journal Article
  Year 2014 Publication Environmental Modelling & Assessment Abbreviated Journal Environmental Modelling & Assessment  
  Volume 19 Issue 5 Pages 389-405  
  Keywords cost-effectiveness; mixed policy; n-input tax; land use policy; nitrogen pollutants; bioeconomic model; mathematical linear programming; miscanthus; nonpoint pollution-control; reed canary grass; biomass production; abatement costs; energy crop; miscanthus; nitrogen; model; efficiencies; instruments  
  Abstract This paper assesses the cost-effectiveness of a mixed policy in attempts to reduce the presence of three nitrogen pollutants: NO (3), N O-2, and NH (3). The policy under study combines a tax on nitrogen input and incentives promoting perennial crops assumed to require low input. We show that the mixed policy improves the cost-effectiveness of regulation with regard to nitrates, whereas no improvement occurs, except for a very low level of subsidy in some cases, for gas pollutants. A quantitative analysis provides an assessment of impacts in terms of land use, farmers’ income, and nitrogen losses throughout France and at river-basin scale.  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1420-2026 ISBN Medium Article  
  Area Expedition Conference  
  Notes (up) TradeM Approved no  
  Call Number MA @ admin @ Serial 4661  
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Author Acharya, T.; Fanzo, J.; Gustafson, D.; Ingram, J.; Schneeman, B.; Allen, L.; Boote, K.; Drewnowski, A.; Ewert, F.; Hall, S.; Hendley, P.; Howden, M.; Janssen, S.; Jones, J.; Latulippe, M.; Lotze-Campen, H.; McDermott, J.; Meijl, H.V.; Nelson, G.; Newsome, R.; Roulin, A.; Scholes, B.; Tanumihardjo, S.; Tavill, G.; van der Mensbrugghe, D.; Wiebe, K. url  openurl
  Title Assessing Sustainable Nutrition Security: The Role of Food Systems: Working Paper Type Report
  Year 2014 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords ftnotmacsur  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C., U.S.A. Editor  
  Language Summary Language Original Title  
  Series Editor ILSI Research Foundation: Center for Integrated Modeling of Sustainable Agriculture and Nutrition Security Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes (up) TradeM Approved no  
  Call Number MA @ admin @ Serial 4995  
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