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Diurnal variation in fecal concentrations of acid-detergent insoluble ash and alkaline-peroxide lignin from cattle fed bermudagrass hays of varying nutrient content

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Journal of Animal Science and Biotechnology 2015年第4期6卷 410-415页

作者： Juvenal Kanani Dirk Philipp Kenneth P Coffey Elizabeth B Kegley Charles P West Shane Gadberry john jennings Ashley N Young Robert T Rhein Division of Agriculture University of Arkansas Department of Plant and Soil Science Texas Tech University

Background： The effect of time of fecal sampling on the accuracy of acid-detergent insoluble ash （ADIA） and alkaline-peroxide lignin （APL） for the prediction of fecal output （FO） in cattle was evaluated. Eight ruminally cannulated cows （594 _＋ 35.5 kg） were allocated randomly to 4 bermudagrass [Cynodon dactylon （L.） Pers.] hay diets markedly different in crude protein concentration （79-164 g/kg） with 2 replicates per diet for 3 periods. Cows were offered hay individually at 20 g DM/kg of body weight daily in equal feedings at 08：00 and 16：00 h for a 10-d adaptation period followed by 5-d of total fecal collection. Fecal grab samples also were taken each day during the fecal collection period at 06：00, 12：00, 18：00, and 24：00 h either directly from the rectum or from freshly voided feces. Samples were composited within cow and time across the 5 d total fecal collection period. Additionally, forage, ort, and fecal samples were analyzed for concentrations of APL and ADIA. Results： Fecal concentrations of ADIA and APL were not affected by sampling time （P 〉 0.22）, even though diet affected （P 〈 0.01） fecal ADIA and APL concentrations. There were no diet x sampling time interactions （P ≥ 0.60）. Estimates of FO and dry matter digestibility （DMD） from ADIA and APL were not affected （P 〉 0.16） by sampling time or the diet x sampling time interaction （P 〉 0.74）. Estimates of FO and DMD from markers from different sampling times or all different combinations of sampling time were not different （P 〉 0.72） from those of total collection among internal markers. Conclusion： Little variation in concentrations of ADIA and APL in daily fecal excretion across time increases flexibility in fecal grab sampling schedules for predicting FO and DMD.

关键词： Digestibility Fecal sampling time Internal markers Bermudagrass Cattle

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Comparison of acid-detergent lignin,alkaline-peroxide lignin,and acid-detergent insoluble ash as internal markers for predicting fecal output and digestibility by cattle offered bermudagrass hays of varying nutrient composition

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Journal of Animal Science and Biotechnology 2014年第3期5卷 310-317页

Background： The potential for acid-detergent insoluble ash （ADIA）, alkaline-peroxide lignin （APL）, and acid-detergent lignin （ADL） to predict fecal output （FO） and dry matter digestibility （DMD） by cattle offered bermudagrass [Cynodon doctylon （L） Pers.] hays of different qualities was evaluated. Eight ruminally cannulated cows （594 ± 35.5 kg） were allocated randomly to 4 hay diets： low （L）, medium low （ML）, medium high （MH）, and high （H） crude protein （CP） concentration （79, 111,131, and 164 g CP/kg on a DM basis, respectively）. Diets were offered in 3 periods with 2 diet replicates per period and were rotated across cows between periods. Cows were individually fed 20 g DM/kg of body weight in equal feedings at 08：00 and 16：00 h for a 10-d adaptation followed by a 5-d total fecal collection. Actual DM intake （DMI）, DMD, and FO were determined based on hay offered, ort, and feces excreted. These components were then analyzed for ADL, APL, and ADIA concentration to determine marker recovery and marker-based estimates of FO and DMD. Results： Forage DMI was affected by diet （P = 0.02）, and DMI from MH and H was greater （P 〈 0.05） than from L. Apparent DMD tended （P = 0.08） to differ among diets while FO （P = 0.20） was not affected by diet treatments. Average ADL recovery （1.16） was greater （P 〈 0.05） than that of ADIA （1.03） and APL （1.06）, but ADIA and APL did not differ （P = 0.42）. Estimates of FO and DMD derived using APL and ADIA were not different （P≥0.05） from total fecal collection while those using ADL differed （P 〈 0.05）. There was no diet by marker interaction （P≥ 0.22） for either FO or DMD. Conclusion： Acid-detergent insoluble ash and APL accurately predicted FO and DMD of cattle fed bermudagrass hay of varying nutrient composition. These internal markers may facilitate studies involving large numbers of animals and forages. Results from such studies may be used to develop improved equations to predict energy values of forages based on the relationship of di

关键词： Acid-detergent insoluble ash Alkaline-peroxide lignin Bermudagrass Cattle Digestibility Marker

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White (Trifolium repensL.) and Arrowleaf (Trifolium vesiculosumSavi) Clover Emergence in Varying Loblolly Pine (Pinus taedaL.) Tree Alley Spacings

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American Journal of Plant Sciences 2019年第4期10卷 659-669页

作者： Taylor C.Adams Dirk Philipp David M.Burner john jennings Becky Mc Peake Amanda J.Ashworth Daniel H.Pote Joan M.Burke Robert Rhein Department of Poultry Science University of ArkansasFayettevilleARUSA Animal Science Department University of ArkansasFayettevilleARUSA Retired US Department of AgricultureDale Bumpers Small Farms Research CenterBoonevilleARUSA Cooperative Extension Service University of ArkansasLittle RockARUSA US Department of Agriculture Poultry Production and Product Safety Research UnitFayettevilleARUSA US Department of Agriculture Dale Bumpers Small Farms Research CenterBoonevilleARUSA

Agroforestry systems have the potential to provide year-long income opportunities via the integrated forage or crop, timber, and livestock. Legumes are an attractive alternative option during the growing season when more traditional forages may not be as productive. The objective of this study was to test the establishment of arrowleaf and white clover grown under varying pine tree alley widths. In 2011, existing forage was removed in 15-yr old loblolly pine tree row alleys of different widths (3.7, 4.9, 7.3, and 9.8 m), including an open area. Arrowleaf, as an annual, was replanted in 2012. Seedlings were counted twice/year, while dry matter was measured three times/year. Photosynthetically active radiation (PAR) was measured in all alley widths to compare light penetration through the canopy. Hot and dry conditions occurred throughout 2012, affecting results. In 2012 and 2013, the greatest PAR for most treatments was observed in June. Seedling counts for all treatments were greatest immediately after establishment, and gradually declined throughout the course of the study. Dry matter yields increased throughout the growing season, and were greatest in arrowleaf clover in the open area on all measurement dates;however, increased weed pressure and repeated flooding affected yields. This study demonstrated that clover establishment in shady wooded areas is possible, but only under suitable environmental conditions.

关键词： White Clover Arrowleaf Clover Dry Matter Yield Seedling Count Agroforestry

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Are Northeastern U.S. forests vulnerable to extreme drought?

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Ecological Processes 2017年第1期6卷 351-363页

作者： Adam P.Coble Matthew A.Vadeboncoeur Z.Carter Berry Katie A.jennings Cameron D.McIntire john L.Campbell Lindsey E.Rustad Pamela H.Templer Heidi Asbjornsen Department of Natural Resources and the Environment University of New Hampshire56 College Rd.114 James HallDurhamNH 03824USA. Earth Systems Research Center University of New Hampshire8 College RoadDurhamNH 03824USA. Northern Research Station USDA Forest Service271 Mast RoadDurhamNH 03824USA. Department of Biology Boston University5 Cummington MallBostonMA 02215USA.

In the Northeastern U.S.,drought is expected to increase in frequency over the next century,and therefore,the responses of trees to drought are important to *** is recent debate about whether land-use change or moisture availability is the primary driver of changes in forest species composition in this *** argue that fire suppression from the early twentieth century to present has resulted in an increase in shade-tolerant and pyrophobic tree species that are drought intolerant,while others suggest precipitation variability as a major driver of species *** this debate,an emerging hypothesis is that mesophication and increases in the abundance of mesophytic genera(e.g.,Acer,Betula,and Fagus)resulted in forests that are more vulnerable to *** review examines the published literature and factors that contribute to drought vulnerability of Northeastern *** assessed two key concepts related to drought vulnerability,including drought tolerance(ability to survive drought)and sensitivity(short-term responses to drought),with a focus on Northeastern *** assessed drought-tolerance classifications for species,which revealed both consistencies and inconsistencies,as well as contradictions when compared to actual observations,such as higher mortality for drought-tolerant *** to drought sensitivity,recent work has focused on isohydric/anisohydric regulation of leaf water ***,based on the review of the literature,we conclude that drought sensitivity should be viewed in terms of multiple variables,including leaf abscission,stomatal sensitivity,turgor pressure,and dynamics of non-structural *** considered drought sensitive(e.g.,Acer,Betula,and Liriodendron)may actually be less prone to drought-induced mortality and dieback than previously considered because stomatal regulation and leaf abscission in these species are effective at preventing water potential from reaching critica

关键词： Acer Betula Drought sensitivity Drought tolerance Quercus Northeastern U.S. Temperate deciduous

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The Impact of COVID-19 on Teenage Homicide Incidence:A Retrospective Review of Forensic Autopsy Cases in Maryland from 2018 to 2021

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Journal of Forensic Science and Medicine 2023年第2期9卷 177-181页

作者： Sahel Sabet Azm Benjamin Shuster Breanna jennings Stephanie Dean john A.Stach Pamela Southall Ling Li Forensic Medicine Graduate SchoolUniversity of Maryland BaltimoreBaltimoreMarylandUSA Office of the Chief Medical Examiner BaltimoreMarylandUSA

Homicides in the United States disproportionately affect minorities,and previous research also indicates that increased economic deprivation and social disorganization correlates with increased rates of *** COVID-19 pandemic has exacerbated economic disparities and may have magnified existing disparities in homicide *** studies have examined the incidence of teenage homicides throughout the United States,especially during the COVID-19 *** was a retrospective case review of homicides involving youth between the age group of 13 and 19 years from 2018 to 2021 in the state of *** aim of this study was to assess COVID-19 affected rates of youth homicide.A total of 230 teenage homicides occurred in Maryland from 2018 to 2021 with 113 cases during the pre-COVID-19 pandemic period(2018/2019)and 117 cases during the COVID-19 pandemic(2020/2021).The majority of teenage homicide victims were African−American *** than 83%and 79%of victims were African−American in 2018/2019 and 2020/2021,*** were also predominantly male(90%in 2018/2019 and 88%in 2020/2021).Maryland has a population of approximately 6 million people and is made up of 23 countries and Baltimore *** half of the overall incidents of teenage homicide took place in Baltimore City(49.6%pre-COVID-19 and 44.4%during COVID-19,respectively).While the average victim age did not vary considerably between 2018/2019(17.8 years)and 2020/2021(17.5 years),the percentage of cases involving victims ages 13-15 years more than doubled from 5.3%of cases in 2018/2019 to 12%of cases in 2020/*** majority of teenage homicide cases were due to firearm injuries(91.7%,n=211),but during the COVID-19 pandemic,there was a rise in violence involving sharp objects such as *** incidence of teenage homicide did not change considerably during the COVID-19 pandemic,although we did observe a trend toward younger males who were African American.

关键词： COVID-19 pandemic medicolegal investigation teenage homicide violence violent crime

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