Land,irrigation water,greenhouse gas,and reactive nitrogen burdens of meat,eggs, and dairy production in the United States

Livestock production impacts air and water quality, ocean health, and greenhouse gas (GHG) emissions on regional to global scales and it is the largest use of land globally. Quantifying the environmental impacts of the various livestock categories, mostly arising from feed production, is thus a grand challenge of sustainability science. Here, we quantify land, irrigation water, and reactive nitrogen (Nr) impacts due to feed production, and recast published full life cycle GHG emission estimates, for each of the major animal-based categories in the US diet. Our calculations reveal that the environmental costs per consumed calorie of dairy, poultry, pork, and eggs are mutually comparable (to within a factor of 2), but strikingly lower than the impacts of beef. Beef production requires 28, 11, 5, and 6 times more land, irrigation water, GHG, and Nr, respectively, than the average of the other livestock categories. Preliminary analysis of three staple plant foods shows two- to sixfold lower land, GHG, and Nr requirements than those of the nonbeef animal-derived calories, whereas irrigation requirements are comparable. Our analysis is based on the best data currently available, but follow-up studies are necessary to improve parameter estimates and fill remaining knowledge gaps. Data imperfections notwithstanding, the key conclusion—that beef production demands about 1 order of magnitude more resources than alternative livestock categories—is robust under existing uncertainties. The study thus elucidates the multiple environmental benefits of potential, easy-to-implement dietary changes, and highlights the uniquely high resource demands of beef.Appreciation of the environmental costs of food production has grown steadily in recent years (e.g., refs. 1–3), often emphasizing the disproportionate role of livestock (4–12). Although potentially societally important, to date the impacts of this research on environmental policies (7, 13, 14) and individual dietary choices have been modest. Although pioneering early environmental burden estimates have tended to address wide food classes (notably the animal-based portion of the diet; e.g., refs. 9 and 15), most policy objectives and individual dietary choices are item specific.For example, a person may consider beef and chicken mutually interchangeable on dietary or culinary grounds. However, even if an individual estimate of the environmental cost of one item exists, it is often not accompanied by a directly comparable study of the considered alternative. Even in the unlikely event that both estimates are available, they are unlikely to consider the costs in terms of more than one metric, and often rely on disparate methodologies. Therefore, environmentally motivated dietary choices and farm policies stand to benefit from more finely resolved environutritional information. Although early work yielded a short list of item-specific environmental cost estimates (16), those estimates were often based on meager data, and addressed a single environmental metric (typically energy), thus requiring expansion, updating, and further analysis to enhance statistical robustness (8).Current work in the rapidly burgeoning field of diet and agricultural sustainability falls mostly into two complementary approaches. The first is bottom–up, applying rigorous life cycle assessment (LCA) methods to food production chains (17–22). Whereas early LCAs focused primarily on greenhouse gas (GHG) emissions (23–26), or in some cases GHGs and energy use (5, 27), more recent LCAs often simultaneously address several additional key metrics (17, 19–21, 28, 29), notably land, water, and reactive nitrogen (Nr, nitrogen fertilizer) use. Some studies also include emissions of such undesirable gases (in addition to GHGs) as smog precursors or malodors (30, 31), or adverse contributions to stream turbidity or erosional topsoil loss (e.g., refs. 32–34). This bottom–up approach is extremely important, and is poised to eventually merge with the top–down national efforts described in the next paragraph. This merger is not imminent, however, because the bottom–up approach considers one or at most a handful of farms at a time. Because of wide differences due to geography (35), year-to-year fluctuations (36), and agrotechnological practice (17, 37), numerous LCAs are required before robust national statistics emerge. Eventually, when a large and diverse LCA sample is at hand, the picture at the national level will emerge. Currently, however, the results from an LCA conducted in Iowa, for example, are unlikely to represent Vermont or Colorado. Given the current volume and scope of LCA research, and the complexity and variability of the problem, LCAs are still too few and too local to adequately sample the multifaceted, diverse US food system, and thus to collectively become nationally scalable.The second agricultural sustainability research thrust, into which this study broadly falls, is a top–down analysis of national (10, 16, 38) or global (8, 39–41) production statistics. The top–down approach we follow here is conceptually straightforward, as described schematically in Fig. 1. The environmental needs (land, irrigation water, etc.) of feed production are collected and distributed among the feed-consuming animal categories. This is termed the partitioning step, and is based on information about the number of animals raised or slaughtered mass in each category, as well as the characteristic feed ration in each category. The burdens attributed to each category are divided by the caloric or protein mass output of that animal category, yielding the final result, the environmental burden per consumed unit (e.g., agricultural land needed per ingested kilocalorie of poultry). This method is mainly appealing because it (i) circumvents the variability issues raised above by using national or global aggregations; and (ii) it is based on relatively solid data. For the United States in particular, US Department of Agriculture (USDA) data tend to be temporally consistent, nearly all-inclusive (e.g., records of the main crops are based on close to 100% of the production), and are reported after some (albeit modest) quality control. The key challenge with this approach is obtaining defensible numerical values and uncertainty ranges for the tens if not hundreds of parameters needed in the calculations, many of which are poorly constrained by available data. Such parameters include, for example, the average feed required per animal per day or per kilogram of weight gain, or the relative fraction of pasture in beef and dairy diets. The values vary as a function of, at least, season, geographical location, and agrotechnology used. One research effort, focused on a single location, is unlikely to yield definitive results. Significant progress in both approaches is primarily realized through the tenacious and painstaking amassing of many independent analyses over time; analyses from which robust, meaningful statistics can be derived. Because of the challenges associated with each of the research thrusts discussed above, quantitatively robust, multimetric estimates that are comparable across different categories and represent the average national environmental burdens have yet to be devised. Although estimates of total national energy use and GHG emissions by agriculture do exist (e.g., refs. 4, 5, 42, and 43), they require further statistical evaluation. The costs in terms of land, irrigation water, and Nr are even less certain.Open in a separate windowFig. 1.A simplified schematic representation of the information flow in calculating environmental burdens per consumed calorie or gram of protein. Feed supply and requirements (blue boxes at top) previously yielded (38) the fraction of each feed class consumed by each animal category; e.g., pork requires 23 ± 9% of concentrated feed. Combined with the environmental burdens (green boxes at left; land, irrigation water, and nitrogen fertilizer for each of the three feed classes), these fractions yield the burdens attributed to each animal category. Finally, dividing those overall environmental burdens attributed to each of the five livestock categories by the number of calories (or grams of protein) nationally consumed by humans in the United States, we reach the final result of this paper (yellow box at bottom). Most input data (left and top boxes) is known with relative accuracy based on USDA data, whereas environmental burdens of pasture and average feed requirements are less certain.Applying a top–down, uniform methodology throughout, here we present estimates of land, irrigation water, GHG, and Nr requirements of each of the five main animal-based categories in the US diet—dairy, beef, poultry, pork, and eggs—jointly providing 96% of the US animal-based calories. We do not analyze fish for two reasons. First, during the period 2000–2013, fish contributed ≈14 kcal per person per day, ≈0.5% of the total and 2% of the animal-based energy (750 kcal per person per day) in the mean American diet (44). In addition, data addressing feed use by fisheries and aquaculture are very limited and incomplete (relative to the five categories considered). We do not claim to cover all important environmental impacts of livestock production. Rather, we focus on key metrics that can be reliably defined and quantified at the national level with currently available data.     

Sleep-wake patterns in children with intrauterine growth retardation

The purpose of this study was to characterize the sleep patterns of children with intrauterine growth retardation, known to be at risk for neurodevelopmental disorders, and seek a possible correlation with behavior, concentration, and attention problems. The sleep patterns of 26 children with intrauterine growth retardation aged 4 to 7 years were compared with those of 47 control children using activity monitors (actigraphs). In addition, data were collected from the parents regarding sleep habits, behavior, concentration, and attention. Children with intrauterine growth retardation aged 4 to 7 years were found to have a tendency toward poorer quality of sleep than their matched controls. This inclination was statistically significant only for one sleep measure, the true sleep time. A tendency toward increased fragmentation of sleep, prolonged waking, and decreased sleep efficiency, although not statistically significant in this study, was demonstrated. Our results showed that 58% of the children with intrauterine growth retardation, compared with 40% of the children in the control group, could be defined as "poor sleepers" (sleep efficiency lower than 90% or three or more waking episodes per night). This disturbed sleep profile is probably an integral part of the neurodevelopmental profile typical of these at-risk children. No significant correlations were found between sleep quality and behavior, concentration, and attention problems.     

Interaction of calbindin D28k and inositol monophosphatase in human postmortem cortex: possible implications for bipolar disorder

OBJECTIVES: Therapeutically relevant concentrations of lithium (Li) exert an uncompetitive inhibition on inositol monophosphatase (IMPase). It has recently been shown that calbindin D28k (calbindin) activates IMPase. Purified calbindin attaches to a specific amino acid sequence on purified IMPase enhancing its activity by several hundred fold. We studied whether calbindin activates IMPase in postmortem human brain crude homogenate, whether differences in calbindin levels between lymphocytes and brain may be responsible for our previous finding of reduced IMPase activity in lymphocytes but not brain of bipolar patients, and whether calbindin protein levels are altered in postmortem brain from bipolar patients versus control subjects and schizophrenic and major depressive patients. METHODS: IMPase activity in human postmortem brain specimens with or without 10 microM human recombinant calbindin was quantified spectrophotometrically in an enzyme-linked immunosorbent assay (ELISA) reader. Calbindin protein levels in postmortem brain were determined using Western blot analysis. RESULTS: Supplementation of human recombinant calbindin to postmortem human brain crude homogenate enhanced IMPase activity by 3.5-fold. No difference in postmortem temporal cortex calbindin protein levels was found between bipolar patients versus comparison groups. Two-fold higher calbindin protein levels were found in Li-treated bipolar patients compared with other bipolar patients. Subchronic Li treatment in mice did not affect brain calbindin protein levels significantly. Chronic Li treatment reduced calbindin protein levels in the frontal cortex but not in the hippocampus. CONCLUSIONS: Calbindin is a physiological activator of IMPase in human brain. Protein levels of calbindin are not altered in postmortem temporal cortex of bipolar patients.     

Association between mutations in the CARD15 (NOD2) gene and Crohn's disease in Israeli Jewish patients

Ulcerative colitis (UC) and Crohn's disease (CD) are heterogeneous disorders characterized by chronic intestinal inflammation. Genetic predisposition is a major risk factor in both diseases. The CARD15 (NOD2) gene has been implied as a candidate gene in the pathogenesis CD. Our aim was to delineate the frequency of three missense and one frameshift variant of CARD15 in Israeli Jewish CD and UC patients. DNA was extracted from blood samples from 238 unrelated inflammatory bowel disease (IBD) patients, 68 with UC and 170 with CD. The DNA was genotyped for two missense mutations, R675W and G881R, and one frameshift mutation, 980FS981X. Mutations in CARD15 were observed with significantly greater frequency in CD patients (46/170, 27%) than in UC patients (7/68, 10%) (P = 0.005). Homozygous and compound heterozygous carriers were restricted to seven (4%) patients with CD as compared to none of the UC patients (P = 0.01). Similar rates in Ashkenazi and non-Ashkenazi Jewish patients were observed. Age-of-onset of disease was lower in Ashkenazi mutation carriers as compared to non-carriers of Ashkenazi origin (18.7 +/- 8.6 years vs. 25.8 +/- 13.4 years, respectively, P = 0.03). No other phenotypic characteristics could distinguish mutation carriers from non-carriers. We conclude that germline mutations in the CARD15 gene are more frequently found in CD than UC patients and appear to predict an earlier age-of-onset in Ashkenazi Jewish patients. No association could be demonstrated between CARD15 mutations and specific disease course or behavior.     

Alginate scaffold for organ culture of cryopreserved-thawed human ovarian cortical follicles

Purpose  

To compare macroporous alginate scaffolds with Matrigel for culturing frozen-thawed human primordial follicles in organ culture.     

Sialylation of ICAM-2 on Platelets Impairs Adhesion of Leukocytes via LFA-1 and DC-SIGN

Intercellular adhesion molecule (ICAM)-2 is highly expressed on platelets and endothelium and is a counter-receptor for the leukocyte integrin, lymphocyte function-associated antigen-1 (LFA-1) and for the dendritic cell-specific, ICAM-grabbing non-integrin (DC-SIGN) protein. In this study, we investigated structural and functional differences between ICAM-2 from platelets and that from endothelial cells. The isoelectric point (pI) of ICAM-2 from HUVEC was pH 3.5-4.3, whereas that of platelet ICAM-2 was more acidic at pH 3.0-3.7. This charge difference was abolished by treatment with N-glycanase or neuraminidase, thus it was due to cell-specific N-linked glycosylation. Purified, immobilized platelet ICAM-2 supported 50% less adhesion of LFA-1-bearing T cells than did purified HUVEC ICAM-2 and no adhesion was observed of monocyte-derived immature dendritic cells via DC-SIGN to platelet ICAM-2. Treatment of platelet ICAM-2 with neuraminidase abolished these functional differences. These findings demonstrated that physiologic sialylation of platelet ICAM-2 renders it less able than endothelial ICAM-2 to support adherence of leukocytes.