Brief Summary of Minutes of Annual Meeting

October 30 Meeting convened at 8:00 AM. Following confirmation of the agenda we proceeded to remarks from the Administrative Adviser. Remarks concerned the timetable and the process to get a new project to replace the current NC-1009 approved. Written guidelines for computer submission of needed documentation were provided. As no CSREES representative was present at the meeting Dr. Benfield reminded us that we had previously received four electronic files with information from CSREES on NRI, budget themes, FY07 budget (president, house and senate versions pending finalization), and NRI personnel. Dr. Benfield also fielded questions from the committee on both topics specific to the project submission and more general questions on funding direction. The committee appreciates Dr. Benfield's commitment to the project. Dr. Chuck Schwab discussed the current state of the Feed Analysis Consortium, inc. (FeedAC, www.feedac.org; formerly the Ruminant Feed Analysis Consortium). For the remainder of the morning discussion was led by Dr. J. McNamara. The discussion during this time considered how the objectives of the new project would relate to each other and to objectives of the current project. Consensus was reached that the past strength of the committee was the breadth of committee members to understand how variations in feed composition interact with the dynamic metabolic processes inherent in the luminal microbial population and animal tissues and that continued interaction and integration was essential to meet the ultimate goal. It was also reaffirmed that improved understanding of these processes was continuous and incremental. Further, there is a commitment to incremental incorporation of knowledge into applied computer models and other quantitative criteria that can be used in the actual practice of feeding cows to optimize economic, food quality and environmental concerns. There was discussion of how qualitative, and semi-quantitative, and quantitative data obtained at microbial or tissue level feeds into ultimate practice. This process will require experimentation at all levels and will also involve additional computer modeling at an intermediate level to aide in integration and sensitivity analysis. This process is by nature iterative and is dependent on interaction among participants working on different aspects with a common goal. After breaking for lunch, the committee reconvened as a whole and then shortly broke up into Objective 1 (feed and microbial oriented) and Objective 2 (tissue metabolism oriented) subgroups with Objective 3 (modeling oriented) participants distributed into these groups. Planned work and opportunities for collaboration were discussed. October 31: Convened at 8:00 AM. Plans of work under objectives 1,2, and 3 were discussed further to explore more potential areas for collaboration. Officers for next year were elected. Armentano (Nov 05-Oct 06 Secretary) was promoted to Chair as per committee tradition. Bequette was elected as secretary (Nov 06- Oct 07) and chair (Nov 07- Oct 08) elect. Meeting for October 2007 (assuming success of the new project proposal) was set for Monday October 22 through noon October 23 in Indianapolis. Donkin offered to aid Armentano with meeting arrangements. McNamara will provide a draft of the project proposal electronically in the week following this meeting. Members were reminded to provide feedback to John McNamara on the proposal in time for a December 1 submission. Chair Hippen is responsible for the annual report and Secretary Armentano is responsible for the minutes (due December 15 in NIMSS). Group adjourned at about 11:00 am.

Objective 1 To quantify properties of feeds that determine the availability of nutrients critical to milk production. Research at PA demonstrated that ruminally protected choline (RPC) and dry propylene glycol (PG) fed to periparturient dairy cows had influences on blood metabolites via different mechanisms and through interactions with each other. Individual or additive effects of RPC or dry PG, however, did not elicit production responses likely due to a relatively positive energy balance based on pre and postpartum BHBA and NEFA values. Further research indicated that, while supplementing RPC, adding PG to the diet increased the demand of B12 for propionate metabolism and therefore, plasma B12 decreased. Without RPC, adding PG had no effect on B12. The absence of response to PG in cows fed no RPC, which also had lower plasma folates, possibly indicate that B12 is not fully available for methylmalonylCoA mutase when the efficiency of methionine synthase is limited by a lack of folates. The effects of monensin (M) on ruminal VFA and plasma glucose (Glu) metabolism was modeled at PA using transition dairy cows and isotopic tracers. WinSAAM, the Windows version of ConSAAM, adequately described and integrated ruminal VFA and blood glucose kinetics, resulting in accurate quantification of VFA and glucose metabolism. Monensin affects interconversions of ruminal VFA, increases propionate originated gluconeogenesis, and reduces glucose disposal rate in transition cows. Effects of concentration and duration of M on milk production efficiency was evaluated in multiparous Holstein cows. Results indicate that, in cows at peak lactation, M effects on ruminal fermentation may be achieved as soon as 10 d of application and short term application of 600 mg/g Rumensin dose may support milk production with a concomitant reduction in intake and no apparent utilization of body energy stores. The correlation (r = -0.66, P= 0.0002) between milk production efficiency and acetate to propionate ratio indicate an involvement of ruminal fermentation in improved feed utilization. Madin-Darby Bovine Kidney cell lines were characterized for use as an in vitro bovine model for peroxisome proliferator-activated receptors (PPARs). The CPT-1 (Carnitine Palmitoyl Transferase-1), ACOX (Acyl CoA Oxidase), LPL (Lipoprotein Lipase) and GAPDH (Glyceraldehyde Phosphate Dehydrogenase) were analyzed using semiquantitative and real time PCR. The results suggest that the MDBK cell line is a promising model to evaluate the role of PPARs for the bovine. (PA). Following research involved treatment of Madin-Darby Bovine Kidney cells with fatty acid PPAR agonists. Of tested fatty acids, palmitate was the most effective at affecting PPAR responsive genes in MDBK cells, followed by linolenic and linoleic while oleic and CLA fatty acids were ineffective. Samples of wet distillers grains from 3 plants were analyzed for fat content by acid hydrolysis/petroleum ether, di-ethyl ether, and fatty acid determination by GLC. (WI) GLC analysis shows significant variation in oil content of these samples. Acid hydrolysis ether extract underestimated fatty acid content and did not correlate well with variation in fatty acid content. Di-ethyl ether also did not correlate much better with fatty acid content. Fatty acid quantification is recommended for determination of fat content in wet distillers grains. In an experiment designed to test the effect of inclusion of protected amino acids, blood meal, or fish meal as high biological value proteins to distillers grains-based diets, milk protein content was improved somewhat by the addition of protected amino acids and blood meal. Diets were not improved by protein supplements designed to improve the lysine delivery of the basal diet, though cows were responsive to an overall improvement in protein amount. (WI) Holstein bull calves were fed starter feeds containing 0, 28, or 56% DDG. (SD) Inclusion of DDG in calf starters increased the number of papillae in rumens per unit area; however the positive influence of this was diminished by decreased size and surface area of individual papillae. Growth of calves were not affected by addition of distillers grains into diets. To determine the effects of feeding corn germ on dairy cow performance, diets for lactating cows were formulated with increasing concentrations of corn germ at 0, 7, 14, and 21% of the diet DM. Inclusion of corn germ at 7% and 14% of dietary dry matter resulted in increased milk and fat yields, however, inclusion of corn germ at 21% of diet DM decreased concentration and yield of milk fat. (SD) To measure the effects of feeding ground flaxseed on BW, BCS, milk yield, milk composition and milk fatty acid profile, 24 Holstein cows fed diets containing whole sunflower seed, ground flax seed, or linseed oil from 7 to 105 DIM. (ND) Cows fed ground flaxseed increased milk fat concentration and yields of FCM and SCM when compared with diets containing linseed oil or whole sunflower seed. To assess the role of protozoa in biohydrogenation (BH) of dietary unsaturated FA, and to determine if inhibition of methanogenesis increased BH, dual-flow continuous culture vessels were modified to retain protozoa. (OH) Experimental treatments were 10-d faunated or defaunated (DEF) sub-periods. Once daily, the fermenters were fed 40 g of a 30:70 concentrate:forage diet containing either no additive, 4% animal-vegetable fat, bromoethanesulfonate (BES 250 µM, methane inhibitor), or monensin ( MON 2.5 µM). Digestibilities of OM and NDF were increased, whereas total VFA concentration decreased by DEF. Methanogenesis was unaffected by defaunation but tended to be decreased by MON. The acetate:propionate ratio decreased and molar proportions of butyrate, isobutyrate, and isovalerate increased by DEF. Isovalerate was increased by MON. Dietary fat increased the flow (mg/day) of the trans (t) BH intermediates t10 and t11, and the effect was more pronounced by DEF. There was no interaction for total t18:1/total unsaturated FA. The flow of CLA was unaffected by DEF or by treatments other than added fat. MON did not affect flows of t10, t11, or total t18:1 FA. Protozoal counts were not different between dietary treatments, but BES increased the generation time from 43.2 to 55.6 h. Subsequent cluster analysis of denaturing gradient gel electrophoresis confirmed a loss of a group of protozoa-associated methanogens (identified by sequence analysis of excised bands). Ruminal, post-ruminal and total tract crude protein (CP) digestion of two low-quality forages originating from central Iranian deserts (Kochia scoparia, Atriplex domorphostegia) were evaluated using in situ, three-step, and DaisyII incubator procedures. (MN) Ruminal CP disappearance of Kochia was lower than Atriplex after 12 h incubation in the rumen, but there was no difference (P > 0.05) between forages after 16 h incubation. Likewise, total tract CP digestion of Kochia (86.6 %) tended to be lower than Atriplex (88.6 %) when using the three-step procedure, while total tract CP digestion of Kochia (88.4%) was significantly less than for Atriplex (91.3%) when using the DaisyII procedure. There was a good relationship between the procedures for evaluating CP digestion of halophyte forages. A combination of in-situ and in vitro evaluations of mechanical-extracted soybean meal with fresh soy gums indicate that application of fresh soy gums onto mechanically extracted soybean meal can increase RUP but that processing can overprotect protein from digestion in the intestine. (MN) Using a three-step procedure to evaluate consistency in processing procedures, intestinal protein digestion of four ruminal protected soybean products and three sources of distillers dried grains with solubles were evaluated. (MN) Variation in processing of each protected soybean product was not great; however mean intestinal protein digestion varied greatly, ranging from 68.2 to 83.0% among the four soybean products. For distillers grains there was a fairly large variation in processing of DDG-A (range of 69.6 to 75.5%), and DDG-C (range of 77.2 to 85.3%). From these types of observations, it appears that the three-step procedure can be a useful method for evaluating quality control of protein within and among processing procedures. (OH) Historically, research evaluating ruminal nitrogen transactions has primarily focused on aspects concerning the degradative, assimilatory and metabolic fates of nitrogenous compounds. The microbiological aspects of these processes have been integrated into nutritional goals of improving the efficiency of microbial protein synthesis, maximizing amino acid supply to the host animal, and (or) minimizing the loss of nitrogenous compounds in animal waste. As described in the paper by Morrison and Yu, microbiological techniques have advanced from phenotypic descriptions of pure and mixed cultures to metagenomic comparisons of population structure in vivo. Correspondingly, although major shifts in microbial populations have been associated with large in vivo treatment differences, more narrow treatment differences have demonstrated shifts in microbial populations that are only relatively comparable to differences among animals fed the same diets, indicating considerable variability in microbial populations occupying similar niches. As nutritionists move toward more sophisticated dietary modeling approaches based on some overall average animal response, we must better account for the variability in model predictions for feeding groups of animals to decrease current reliance on dietary safety factors and anecdotal animal assessment strategies to prevent ruminal acidosis or shortages of rumen degraded protein. Dietary factors influencing ruminal degradative capacity and outflow of microbial protein include the types and numbers of protozoa, the availability of specific nitrogenous and carbohydrate fractions, rumination activity, stratification and location in the rumen, and time after feeding. Diet, fecal, urine, and manure samples were collected from dairies in the Pacific Northwest and analyzed for chemical and isotopic composition and for ammonia volatilization rates in vitro (ID). Cumulative ammonia loss was estimated based on daily emissions and daily manure and ammonia samples were analyzed for 15N abundance. Correlations between cumulative ammonia losses and 15N abundance of manure N ranged from r = 0.70 to r = 0.92 and the relationship was linear. This study demonstrated that ammonia emitted from cattle manure during storage is highly depleted in 15N and changes in 15N of aged manure could potentially be used to predict ammonia emissions from cattle manure. Sugar supplementation can stimulate rumen microbial growth and possibly fiber digestibility; however, increasing ruminal carbohydrate availability relative to RDP can promote energy spilling by microbes or decrease rumen pH. Therefore, an experiment was conducted with lactating cows to determine the effects of matching molasses supplementation with urea and monensin supplementation on corn silage (CS) or alfalfa hay (AH)-based diets. (OH) All diets were balanced to have 16.2% CP, 18.0% forage NDF and 41.0% NFC. Treatments had no effect on milk or protein yield, but monensin decreased milk fat from 3.25 to 2.72 % in CS diets but not in AH diets. Rumen ammonia concentration decreased with the addition of molasses but increased with molasses + urea in the CS diets. Ammonia and MUN remained unchanged in the AH diets. Diets did not affect (P>0.21) ruminal pH or DMI. Sugar supplementation might require urea to support microbial protein synthesis in corn silage diets balanced for moderate CP and perhaps especially if monensin is fed. To compare the effects of whole plant silage and grain produced from NutriDense® (ND), leafy NutriDense® (LND), or a conventional yellow dent (YD) hybrid on rumen fermentation, total tract nutrient digestibility, and performance 20 multiparous Holstein cows, four of them surgically fitted with ruminal cannulas, were fed diets containing 30.6% corn silage and 27.7% corn grain provided from the three hybrids. (IL) Feeding ND grain and (or) LND silage reduced the intakes of nonfibrous carbohydrates and starch but increased the intake of ether extract. Apparent digestibility of starch in the total tract was highest for the diet that contained LND silage and YD grain, whereas the amount and percentage of ether extract that was apparently digested in the total tract was increased and tended to be increased, respectively, by the addition of ND grain and (or) LND silage to the diets. Ammonia nitrogen in the ruminal fluid tended to be increased by feeding ND grain and (or) LND silage as did concentration of milk urea nitrogen. The ND grain and LND silage were similar to the conventional grain and silage for the feeding of lactating dairy cows. Objective 2 To quantify metabolic interactions among nutrients that alter synthesis of milk. The mRNA levels of NADP+-dependent isocitrate dehydrogenase (IDH1) have been observed to increase by 2.3-fold after parturition compared to late pregnancy and remained elevated thereafter. (AZ) Quantification in changes of IDH1 expression showed that IDH1 mRNA increased in parallel with ²-casein expression induced by extracellular matrix. Fetal calf serum and insulin repressed, whereas prolactin stimulated the expression of IDH1 mRNA in a dose-dependent fashion. Inhibitory effects of insulin on IDH1 mRNA levels were antagonized by cotreatment with prolactin. In contrast, treatment with prolactin in the presence of extracellular matrix further increased IDH1 mRNA and protein accumulation. Prolactin-induced IDH1 expression was inhibited by the mitogen-activated protein kinase (MAPK) inhibitors PD98059 and U0126, and Janus tyrosine kinase 2 (Jak2) inhibitor AG490, suggesting that both MAPK and Jak2 contribute to regulation of IDH1 expression by prolactin. Finally, treatment of BME-UV cells with ±-ketoglutarate and palmitic acid reduced IDH1 transcript levels. Expression of IDH1 in bovine mammary epithelium is modulated by regulators of differentiation including extracellular matrix and lactogenic hormones as well as metabolic effectors. Pilot tracer and gene expression were studied in lactating mice (days 11-13). (MD) Initial findings confirm those observed with bovine mammary explants in that plasma glucose is not the sole nor main source of carbon skeletons for mammary lactose (glucose and galactose) synthesis. In fact, over 50% of lactose is synthesized de novo within the mammary gland of the mouse with nearly equal contributions from the Krebs cycle (via PEPCK-c) and from plasma glycerol. Gene expression of PEPCK isoforms in the liver and in the mammary glands were similar to those previously observed in the bovine mammary gland. Flux and contributions to overall Krebs cycle metabolism of primary substrates available to the rumen and small intestinal tissues were determined by using rumen epithelial (REC) and duodenal mucosal cells (DMC) isolated from Angus bulls. Data suggest that the partial catabolism of glucose to lactate and possibly alanine may play a role in conserving glucose 3-carbon units for hepatic gluconeogenesis. Furthermore, increasing the supply of glutamate to REC and DMC increased the flux of Krebs cycle intermediates from glutamate, thereby reducing the entry of other substrates entering at or beyond ±-ketoglutarate.(MD) In order to better understand transcriptional regulation of phosphoenolpyruvate carboxykinase (PEPCK), a rate-limiting enzyme for gluconeogenesis, an experiment was conducted to clone and sequence the bovine PEPCK gene and to identify promoter elements. (IN) Bovine genomic sequence information, available through the National Center for Biotechnology Information (NCBI) and BLAST searched for matches to the 5 end of PEPCK-C based on sequence data previously generated in our laboratory by cDNA cloning (Genbank accession: NM_174737) allowed cloning of a 1000 bp sequence that included the first few bases of the coding region and ligated the sequence to a luciferase reporter gene. Promoter truncations have been generated. In efforts to characterize the effect of dexamethasone treatment on induction of gluconeogenesis in cattle through pyruvate carboxylase (PC), putative glucocorticoid response elements in the second and third promoter region of bovine PC have been identified. (IN) Approximately 1200 bp upstream of the first exon that is associated with each of the three promoters of bovine PC was amplified from bovine genomic DNA. Promoter/reporter constructs were generated for each promoter region. Promoters were truncated from the 5 end to generate a series of constructs for each of the three promoters which have been transfected separately into rat hepatoma H4IIE cells. Stable cell lines containing the promoter constructs have been selected and amplified. Experiments are ongoing to determine the minimal promoter elements necessary for activity of each promoter and responsiveness to glucocorticoids. Injection of cows with 5mg/d of glucagon and glucagon plus 500 ml/d of glycerol drench for 14 d after calving increase plasma glucose and insulin and decrease NEFA concentration on a short-term basis. (IA) Glucagon plus glycerol decreased total liver lipids and increase liver glycogen content. Furthermore, glycerol decreased plasma NEFA concentration and accelerated hepatic TAG removal. These responses suggest that glucagon, glycerol, and glucagon plus glycerol have the potential to treat fatty liver disease in dairy cows. Poor biological efficiency of nitrogen (N) use decreases farm profitability and results in substantial N waste. If we could find ways to produce high quantities of milk per cow with only 15% CP diets, we could decrease urinary N excretion by ~40%. To identify genes associated with metabolism that are key regulatory points and are up- or down-regulated by protein-deficient diets, 12 lactating cows were fed either a standard diet fed to high-producing lactating cows with ~19% protein or diets containing 11 or 15% CP. (MI). Feeding 11% CP for 10 d reduced milk yield 16%, increased the conversion of feed N to milk N by 47%, and decreased milk urea nitrogen (MUN) 66%. Feeding 11% CP for 3 d increased the efficiency of N use 54% and dramatically decreased urinary N excretion 67%. With increased dietary protein, we observed a linear increase in BUN and MUN and a linear decrease in creatinine. As the calculated body protein balance indicates, this was not a sustainable metabolic adaptation. Gene expression in tissues using our BMET microarray is an ongoing evaluation. A study on dietary protein requirements evaluated the effects of phase feeding on lactation performance. (AL) Cows in 4 pens, two pens per treatment were fed either a standard 17% or a 13 and a 17% CP diet on a three day cycle for 24 d periods in a double switchback design. Diet had no effect on milk production, but milk protein content for the 17% CP diet was 3.34% compared with 3.21% for the phase-feeding treatment. To: 1) establish the relationship between transfer of blood urea-N to and utilization of recycled urea-N within the digestive tract (GIT) and 2) establish the relationship between plasma urea concentration and urea-N recycled to the GIT, independent of diet induced events occurring within the GIT, 4 sheep (28.1 ± 0.6 kg) were fed a low protein (6.8% CP, DM basis) diet and assigned to four rates of i.v. urea infusion (0, 3.8, 7.5, 11.3 g urea-N/d; 10-d periods) according to a balanced 4 X 4 Latin square design. Results suggests that transfer of blood urea to the GIT is highly dependent upon blood urea concentration and it is less limiting for nitrogen retention than is the efficiency of capture of recycled urea-N by microbes in the GIT. (MD) To determine the effect of reducing ruminally degradable protein (RDP) with constant ruminally undegradable protein in mid-lactation dairy cow diets 40 mid-lactation Holstein and Jersey by Holstein cross-bred cows were fed diets with CP contents of 18, 16.8, 15.7, or 14.5% and formulated RDP contents of 11.3, 10.4, 8.5 and 7.6% of dry matter, respectively. (VA) Milk urea nitrogen decreased linearly as the CP content of the diets declined. Results suggest that mid-lactation dairy cows can be fed diets with RDP contents as low as 8.5% of dry matter, which is less than that recommended by NRC (2001). The use of principal component analysis (PCA) and multivariate analysis (MA) to assess the relationship between milk fatty acid (FA) concentration (%) of total FA methyl esters) and diet induced milk fat depression (MFD) was examined. (MD) The PCA and MA analysis in the present study, confirms previous reports that t10-18:1 may be involved in MFD and suggest that t6,7,8-18;1 could also be important in MFD. Among the CLA isomers, the t10c12 CLA and t7c9 CLA isomer were consistently negatively correlated to milk fat percentage. Following PCA, a lactating mouse model was used to re-examine isomeric effects on fat depression. The study treatments were: 1) c18: 1- c9 (oleic acid)-Control; 2) Partially hydrogenated vegetable fat (negative control), 3) t7-18:1; 4) t9-18:1; 5) t11-18:1; and 67) t10c12-18:1 at 5% of total calories. A preliminary report showed that t10c12-18:1 and t7-18:1 depressed milk fat, confirming our principal components analysis. The relationships between mammary gene expression patterns were examined along with effects of a milk fat-depressing diet (MFD) on mammary gene expression patterns using microarray technology. (MD). Differentially expressed genes included 21 associated with insulin action, 24 with glucose metabolism, and 27 with cytokine action. Mammary from MFD had >3-fold down regulation for a gene encoding a novel nuclear protein responsible for normal triglyceride synthesis and induction of key lipogenic genes (e.g.PPARs, CEBPs) in mice. These data showed that milk fat depression is associated with complex changes in mammary transcript expression patterns. The lactation performance of dairy cows fed wet distillers grains (WDG) for a complete lactation was evaluated. (SD) Relative to a control diet not containing distillers grains, feeding of WDG at 15% of diet DM for the entire lactation increased milk component percentage and yields, feed efficiency, body condition and body weight gain while maintaining milk yield and feed intake. Feeding 15% of diet as WDG during the dry period through early lactation (-60 to 70 DIM) did not effect production of milk but increased milk protein content, BW, and BCS. Objective 3 To use these quantitative relationships to challenge and refine computer-based nutrition systems for dairy cattle. Recent model evaluations have looked at the sensitivity of model predictions to changes in nutrient content based on the underlying belief that knowing the impact of these pertubations on model predictions would allow for better allocation of resources when choosing nutrient analysis. In attempts to define the level of precision reasonably achievable by models, a dataset is being constructed from recently (past 3 to 5 years) published literature. The data set will be used to define the precision with which measures of economic importance related to milk production for dairy farms can be measured. (Akey) Because reports indicate that the 2001 NRC young calf sub-model tends to under-predict growth of calves and there is a known relationship between growth rate of replacement heifers and lactation performance, attempts to determine if there is a systemic bias to the sub-model are being made. Current efforts are to program the young calf sub-model into a spreadsheet format so that individual equations can be explored. It has been observed previously that the digestion and metabolism model known as Molly underpredicts milk component yield responses to nutrition and consequently overpredicts body energy store responses. (VA) To further account for this, cows were fed 0, 3, or 6 kg of concentrate daily throughout 670 d of lactation. Milk synthesis parameters for Molly and a more simple lactation model were fitted to the data to allow comparisons of model structure. The original model predicted lactose, protein, and fat yields with root mean square prediction errors (RMSPE) of 17.8%, 22.4%, and 20.1%, respectively. The RMSPE for predictions of lactose, protein, and fat yields by the revised model were 8.7%, 10.2%, and 11.8%, respectively with slope bias of 6.8, 2.8, and 2.8% of the MSPE, respectively. The RMSPE for predictions of body weight by Molly95 was 19.3% with mean and slope bias of 62.1 and 20.7%, respectively as compared to a RMSPE of 7.3% for the revised model with mean and slope bias of 9.7 and 2.9%, respectively. It was concluded that representing mammary synthetic capacity as a function of active cell numbers had merit relative to the original representation of mammary synthetic capacity in Molly. Using models, Molly and CPM Dairy, nutrient inputs were varied to assess their importance in animal outputs using typical CA dairy rations. (CA) The nutrient levels that varied were soluble carbohydrate (SC), starch, crude protein (CP), soluble CP (PS), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (LG), ether extract (EE), lysine and methionine and nutrients were varied individually, +/- 20% from base values. Animal outputs used to assess impacts of changes in ration nutrient inputs on model predictions were fecal nitrogen (N), urinary N, milk N (Molly only), microbial dry matter, milk (ME, MP and AA allowable milk in CPM Dairy), milk fat (Molly only) and milk protein (MP allowable milk protein in CPM Dairy). Both models had similar sensitivities to ration nutrient changes, and there was very little difference in model responses among rations. For both models, predicted animal outputs were most sensitive to changes in CP, NDF and PS (LG in CPM only; EE in Molly only) supporting the need for chemical analysis of these nutrients. Molly was sensitive to an amino acid (AA), even if it was not limiting animal production, due to N excretion in milk and urine. Estimated AA allowable milk in CPM was the only output that was sensitive to a limiting AA. Both models were insensitive to changes in SC, and ADF, indicating that model libraries for these values are adequate for ration formulation and/or evaluation.

Refereed publications of NC-1009 Committee members during 2006

Ametaj, B.N., B.J. Bradford, G. Bobe, R.A. Nafikov, Y. Lu, J.W. Young, and D.C. Beitz. 2005. Strong relationships between mediators of the acute phase response and fatty liver in dairy cows. Can. J. An. Sci. 85:165-175. Bateman, H. G., II, A. E. Beem, C. C. Stanley, C. C. Williams, and C. F. Hutchison. 2005. Case study: Using urine pH as a predictor for ketosis in transition dairy cows. Prof. Anim. Sci. 21:515-520. Benefield, B.C., M. Liñeiro, I.R. Ipharraguerre, and J.H. Clark. 2006. NutriDense Corn Grain and Corn Silage for Dairy Cows. J. Dairy Sci. 89:1571-1579. Chung, Y. H., H. G. Bateman, II, C. C. Williams, C. C. Stanley, D. T. Gantt, T. W. Braud, L. L. Southern, J. D. Ward, P. G. Hoyt, and G. A. Sod. 2006. Effects of methionine and lysine on fermentation in vitro and in vivo, nutrient flow to the intestine, and milk production. J. Dairy Sci. 89:1613-1620. DeFrain, J. M., A. R. Hippen, K. F. Kalscheur 2006. Feeding lactose to increase ruminal butyrate and the metabolic status of transition dairy cows. J. Dairy Sci. 89:267-276. DeFrain, J. M., Hippen, A. R., Kalscheur, K. F., J. M. Tricarico. 2005. Effects of dietary alpha-amylase on metabolism and performance of transition dairy cows. J. Dairy Sci. 88 (12):4405-4413. Douglas, G. N., T. R. Overton, H. G. Bateman, II, H. M. Dann, and J. K. Drackley, 2006. Prepartal plane of nutrition, regardless of dietary energy source, affects periparturient metabolism and dry matter intake in Holstein cows. J. Dairy Sci. 89: 2141-2157. Drackley, J.K., S.S. Donkin, and C.K. Reynolds. 2006. Invited Review. Major Advances in Fundamental Dairy Cattle Nutrition. J. Dairy Sci. 89 1324-1336. Edwards, J.E., Bequette, B.J., McKain, N., McEwan, N.R., & Wallace, R.J. (2005) Influence of flavomycin on microbial numbers, microbial metabolism and gut tissue protein turnover in the digestive tract of sheep. Br. J. Nutr. 94: 6470. El-Kadi, S.W., Baldwin, R.L.VI., Sunny, N.E., Owens, S.L., Bequette, B.J. (2006) Intestinal protein supply alters amino acid, but not glucose, metabolism by the sheep gastrointestinal tract. J. Nutr. 136: 12611269. Fadel, J. G. 2004. Estimating parameters of non-linear segmented models. Journal of Dairy Science. 87:169173. Firkins, J. L., A. N. Hristov, M. B. Hall, and G. A. Varga. 2006. Integration of ruminal metabolism in dairy cattle. J. Dairy Sci. 89:5561-5586. Golombeski, G. L, K. F. Kalscheur, A. R. Hippen, D. J. Schingoethe. 2006. Slow-release urea and highly fermentable sugars in diets fed to lactating dairy cows J. Dairy Sci. 89: 4395-4403. Gressley, T. F., S.M. Reynal, J.J. Olmos Colmenero, G.A. Broderick and L.E. Armentano. 2006. Development of a tool to insert abomasal infusion lines into dairy cows. J. Dairy Sci. 89: 3965-3967. Hammon, H. M., C. Philipona, Y. Zbinden, J.W. Blum, and S.S. Donkin. 2005. Effects of Dexamethasone and Growth Hormone Treatment on Hepatic Gluconeogenic Enzymes in Calves. J. Dairy Sci. 88:2107-2116. Hanigan, M.D., France, J., Mabjeesh, S.J., McNabb, W.C., MacRae, J.C., and Bequette, B.J. (2005). Mammary protein turnover estimated from phenylalanine kinetics in the lactating dairy goat. Can. J. Anim. Sci. 85: p. 548. Hill, T. M., J. M. Aldrich, R. L. Schlotterbeck, and H. G. Bateman, II. 2006. Effects of feeding calves different rates and protein concentrations of twenty percent fat milk replacers on growth during the neonatal period. Prof. Anim. Sci. 22:252-260. Hill, T. M., J. M. Aldrich, R. L. Schlotterbeck, and H. G. Bateman, II. 2006. Effects of feeding rate and concentrations or protein and fat of milk replacers fed to neonatal calves. Prof. Anim. Sci. 22:374-381. Jacobs, J. L., F, Diez-Gonzalez, R. L. Phillips and M. D. Stern. 2005. Detection of transgenic maize Cry1Ab protein subjected to ruminal digestion. J. Anim. Feed Sci. 14(4):655-664. Liu W, Degner SC, Romagnolo DF. 2006. Trans-10, Cis-12 Conjugated Linoleic Acid Inhibits Prolactin-Induced Cytosolic NADP+-Dependent Isocitrate Dehydrogenase Expression In Bovine Mammary Epithelial Cells. J. Nutr. 136:2743-2747. Mesgaran, M. D. and M. D. Stern. 2005. Ruminal and post-ruminal protein disappearance of various tropical feeds determined by the mobile nylon bag, in vitro and three-step procedures. Anim. Feed Sci. Technol. Vol 118/1-2:31-46. Nafikov, R.A., B.N. Ametaj, G. Bobe, K.J. Koehler, J.W. Young, and D.C. Beitz. 2006. Prevention of fatty liver in transition dairy cows of subcutaneous injections of glucagon. J. Dairy Sci. 89:1533-1545. Oba, M., Baldwin, R.L., IV, Owens, S.L, & Bequette, B.J. (2005) Metabolic fates of ammonia nitrogen in ruminal epithelial and dudoenal mucosal cells isolated from growing sheep. J.Dairy Sci. 88: 3963-3970. Reveneau, C., C.V.D.M. Ribeiro, M.L. Eastridge, N.R. St-Pierre, and J.L. Firkins. 2005. Processing whole cottonseed moderates fatty acid metabolism and improves performance by dairy cows. J. Dairy Sci. 88:4432-4355. Tapia, M. O., M. D. Stern, A. L. Soraci, R. Meonuck, W. Olson, S. Gold, R. L. Koski-Hulbert, and M. J. Murphy. 2005. Patulin-producing molds in fermented feeds and effects of patulin on fermentation by ruminal microbes in continuous culture. Anim. Feed Sci. Technol. 119:247-258. Ure, A.L., T.R. Dhiman, M.D. Stern and K.C. Olson. 2005. Treated extruded soybean meal as a source of fat and protein for dairy cows. Asian-Aust. J. Anim. Sci. 18(7):980-989. Velez, J.C. and S.S. Donkin. 2005. Feed Restriction Induces Pyruvate Carboxylase but not Phosphoenolpyruvate Carboxykinase in Dairy Cows. J. Dairy Sci. 88: 2938-2948. Wheeler, E. F., P.A. Topper, Y. G.A. Varga, N. Brown, R.E Graves. V. Ishler, A.J. Heinrichs. V Blanes Vidal. 2006. Ammonia emission monitoring using flux chamber methods. In Proceedings AgEng 2006, World Congress. Bonn, Germany. 8 pp on CD. Wheeler, E.F., P.A. Topper, G.A. Varga, N. Brown, V. Blanes-Vidal, A.J. Heinrichs, T.L. Richard. R.E. Graves and V. Ishler, G.I. Zanton, and M.L. Moody. 2006. Reducing ammonia emission from dairy housing using nutritional strategies. In Proceedings Agricultural Air Quality Workshop, Washington DC. pp. 1229-1235. Williams, E.L., S.M. Rodriguez, D.C. Beitz, and S.S. Donkin. 2006. Effects of short-term glucagon administration of gluconeogenic enzymes in the liver of midlactation dairy cows. J. Dairy Sci. 89:693-703. Williams, E.L., S.M. Rodriguez, D.C. Beitz, and S.S. Donkin. 2005. Effects of short-term glucagon administration on gluconeogenic enzymes in the liver of mid-lactation dairy cows. J. Dairy Sci. 89:693-703. Williams, E. L., M. M. Pickett, G. A. Varga, and S. S. Donkin. 2006. Effect of dietary carbohydrate and monensin on expression of gluconeogenic enzymes in liver of transition dairy cows. J. Anim. Sci. (In Press). Book chapters and reviews during 2006 Bequette, B.J., Sunny, N.E., El-Kadi, S.W., & Owens, S.L. (2006) Application of stable isotopes and mass isotopomer distribution analysis to the study of intermediary metabolism of nutrients. J. Anim. Sci. 84(E. Suppl.):E50-E59. (Invited Review). Boston, R. C. and M. D. Hanigan. (2006). Segmented, constrained, nonlinear, multi-objective, dynamic optimization methodology applied to the dairy cow ration formulation problem in a situation where some of the constraints may be discontinuous. In: J. Dijkstra (Ed.) Modelling Nutrient Utilization in Farm Animals. Wageningen. pp 257-274. Firkins, J.L. and Z. Yu. 2006. Characterisation and quantification of the microbial populations of the rumen. Pages 19-54 in Ruminant Physiology, Digestion, Metabolism and Impact of Nutrition on Gene Expression, Immunology and Stress. K. Sejrsen, T. Hvelplund, and M.O. Nielsen, eds. Wageningen Academic Publishers, Wageningen, The Netherlands. Hanigan, M. D., H. G. Bateman, J. G. Fadel, J. P. McNamara, and N. E. Smith. (2006). An ingredient-based input scheme for Molly. In: J. Dijkstra (Ed.) Modelling Nutrient Utilization in Farm Animals. Wageningen. pp. 328-348. Hanigan, M. D., H. G. Bateman, J. G. Fadel, J. P. McNamara, and N. E. Smith. 2006. An ingredient-based input scheme for Molly. In: Nutrient digestion and utilization in farm animals: Modelling Approaches. ed. E. Kebreab, J. Dijkstra, A. Bannink, W. J. J. Gerrits, and J. France. CAB Publishing. p 328-348. Non-refereed publications during 2006 Bequette, B. Can we define nutrient requirements by following the metabolic highways of macronutrient use? Nutritional Sciences Series lecture, The Ohio State University (Columbus, OH) (May 20, 2005). Bequette, B. Mammary Gland Requirements. Eleventh DISCOVER Conference on Food Animal Agriculture: Amino Acid Requirements of Dairy Cows. Nashville, IN (August 28-31, 2005). Bequette, B. Mass Isotopomer Distribution Analysis for Studying Intermediary Macronutrient Metabolism. FASS Joint Meeting Symposium Stable Isotope Tracer Techniques for Non-ruminant Nutrition Research and Their Practical Applications, Cincinnati, OH, (July 26, 2005). Bequette, B. Reducing nitrogen excretion in ruminants: The potential to increase urea recycling. 3rd Mid-Atlantic Nutrition Conference, Timmonium, MD, (March 24, 2005). Bequette, B. Regulation of key metabolic processes in lactation. FASS Joint Meeting Symposium Exploring the Boundaries of Efficiency in Lactation: Metabolic Relationships in Supply of Nutrients in Lactating Cows (co-presentation with S. Donkin, Purdue), Cincinnati, OH, (July 25, 2005) Bequette, B. The roles of amino acids in milk yield and components. 17th Florida Ruminant Nutrition Symposium. Gainesville, FL. (February 1-2, 2006). Hill, M., R. Schlotterbeck, J. Aldrich, and G. Bateman. True or false? Feeding calves accurately is easy. Hoards Dairyman July 10, 2006. pp. 480. Ipharraguerre, I.R., and J.H. Clark. 2006. Dairy Cow Response to Sources and amounts of Supplemental Protein. Illinois Dairy Report. Pp. 11-15. Ipharraguerre, I.R., and J.H. Clark. 2006. Effects of Source of Supplemental Protein on Nitrogen Passage to the Small Intestine. Illinois Dairy Report. Pp. 16-20. Ishler, V. and G. A. Varga. 2005. How to use NDF digestibility information in ration balancing. Hoards Dairyman. Osman, M., N. Mehyar, G. Bobe, J. Coetzee, and D. Beitz. 2006. Acute effects of subcutaneous injection of glucagon and/or oral administration of glycerol on blood metabolites and hormones of Holstein dairy cows affected with fatty liver disease. A.S. Leaflet R2090. ISU Animal Industry Report. Richard, T., E. Wheeler, and G .A. Varga. 2005. Strategies for reducing gas emissions from dairy farms. Dairy Nutrition Conference, Grantville, PA. Varga, G. A. 2006. Things to look for to determine if you are doing a good job with emphasis on transition cow and early lactation. Feed Compounder, January. Seminars and Invited Presentations during 2006 Stern, M. D., A. Bach and S. Calsamiglia. 2005. New concepts in protein nutrition of ruminant animals. Proc. XII Biennial Congress of the Mexican Assoc. of Specialists in Anim. Nutr. (AMENA). Pages 1-25. Stern, M. D., A. Bach and S. Calsamiglia. 2006. New concepts in protein nutrition of ruminants. Proc. 21st Ann. Southwest Nutr. & Management Conf. Proc. p. 45-66. Published abstracts during 2006 Arieli, A., C. M. Martinez, T. W. Cassidy, and G. A. Varga. 2006. Effects of concentration and duration of Rumensin application on milk production efficiency in multiparous Holstein cows. J. Dairy Sci. 89:126 Abdelqader, M. M., A. R. Hippen, D. J. Schingoethe, K. F. Kalscheur, K. Karges, M. L. Gibson. 2006. Corn germ from ethanol production as an energy supplement for lactating dairy cows. J. Dairy Sci. 89(Suppl 1):156 (abstr). Bach, A., S. Calsamiglia and M. D. Stern. 2005. Nitrogen metabolism in the rumen. J. Dairy Sci. 88 (E. Suppl.).E9-E21. Bequette, B.J., Owens, S.L., El-Kadi, S.W., Sunny, N.E., & Shamay, A. (2005) Use of 13C-mass isotope distribution analysis (MIDA) to define precursors for lactose and amino acid synthesis by bovine mammary explants. J. Dairy Sci. 88(Suppl. 1):289. Bionaz, M., E. Shirk, J. P. Vanden Heuvel, C. R. Baumrucker, E. Block, and G. A. Varga. 2006. Treatment of Madin-Darby Bovine Kidney cells with fatty acid PPAR agonists. J. Dairy Sci. 89:335 Bionaz, M., C. R. Baumrucker, J. P. Vanden Heuvel, E. Block, G. A. Varga. 2006. Characterization of Madin-Darby Bovine Kidney cell line for PPARs. J. Dairy Sci. 89:335 Brown, A.W., M.M. Bohan, N. Mehyar, A.H. Trenkle, and D.C. Beitz. 2006. Effects of TNF-alpha as a simulated stressor on adipose and liver tissues from rats fed varying diets. FASEB J. 20:A126. Brown, N., V. Ishler, R. Chung, T. Cassidy, K. Hyler and G. A.Varga. 2005. Effect of forage processing and corn particle size on milk production and composition, and nutrient digestibility for high producing Holstein dairy cows. J. Dairy Sci. 88 (Suppl 1): 99. Chung, Y. H., T. W. Cassidy, I. D. Girard, P. Cavassini and G. A. Varga. 2005. Effects of rumen protected choline and dry propylene glycol on production responses of periparturient Holstein dairy cows. J. Dairy Sci. 88 (Suppl 1): 61 Chung, Y.-H., T. W. Cassidy, I. D. Girard, P. Cavassini, and G. A. Varga. 2005. Effects of rumen protected choline and dry propylene glycol on feed intake and blood metabolites of Holstein dairy cows. J. Dairy Sci. 88 (Suppl 1): 61 El-Kadi, S., Baldwin, R., VI, Sunny, N., Owens, S.L., & Bequette, B.J.. (2005) Postruminal protein infusion increases leucine use by the gastrointestinal tract of sheep while glucose utilization remains unchanged. J. Anim. Sci. 83 (Suppl. 1):128. Firkins, J. L., A. N. Hristov, M. B. Hall, and G. A. Varga. 2005. Integration of ruminal metabolism in dairy cattle. J. Dairy Sci. 88 (Suppl 1): 124. Firkins, J.L. 2006. Ruminal nitrogen metabolism: The current nutritional outlook. J. Dairy Sci. 89 (Suppl. 1):153. Firkins, J.L., A.N. Hristov, M.B. Hall, G.A. Varga, and N.R. St-Pierre. 2006. Integration of ruminal metabolism in dairy cattle. J. Dairy Sci. 89 (E. Suppl.):E31-E51. Galbreath, C.W., M.R. ONeil, J.D. Kirsch, J.W. Schroeder, K.G. Odde, G.P. Lardy, K.A. Vonnahme. 2006. Effect of feeding flax or linseed meal on progesterone clearance rate in ovariectomized ewes. J. Anim. Sci. (Abstr.). Girard, C. L., Y.-H. Chung, and G.A.Varga. 2006. Effects of rumen protected choline and dry propylene glycol supplements on plasma concentrations of folates and vitamin B12 in periparturient Holstein dairy cows. J. Dairy Sci.89:230. Hanigan, M. D., H. G. Bateman, J. G. Fadel, and J. P. McNamara. (2006). Metabolic models of ruminant metabolism: recent improvements and current status, J. Dairy Sci. E Suppl: E52-E64. Hanigan, M. D., H. G. Bateman, J. G. Fadel, and J. P. McNamara. 2006. Metabolic Models of Ruminant Metabolism: Recent Improvements and Current Status. J. Dairy Sci. 89:E52-E64. Hanigan, M. D., H. G. Bateman, J. G. Fadel, J. P. McNamara. 2006. Metabolic models of ruminant metabolism: recent improvements and current status. Journal of Dairy Science. 89 (E. Suppl.): E52-E64. Hill, T. J. Aldrich, H. Bateman, and R. Schlotterbeck. 2006. Effect of altering theoretical rumen undegraded soybean protein in a calf starter. J. Dairy Sci. 89(Suppl. 1): 437 (Abstr.). Hill, T., J. Aldrich, H. Bateman, and R. Schlotterbeck. 2006. Effect of altering theoretical rumen degraded and metabolizable protein in a calf starter. J. Dairy Sci. 89(Suppl. 1): 437 (Abstr.). Hristov, A.N., L. Campbell, and J. H. Harrison. 2006. Evolution of 15N abundance in cattle manure in relation to cumulative ammonia losses. J. Dairy Sci. 89 (Suppl. 1):357. Kadegowda, A. K. G., L. S. Piperova, and R. A. Erdman Principal component and multivariate analysis of milk fatty acid composition data from experiments designed to induce dietary milk fat depression in lactating cows. 2005. J. Dairy Sci. Vol. 88(Suppl. 1):176. Karnati, S.K.R., C.V.D.M. Ribeiro, J.T. Sylvester, and J.L. Firkins. 2006. Inhibition of methane synthesis on biohydrogenation in the presence or absence of protozoa in continuous culture. J. Dairy Sci. 89(Suppl. 1):127. Karnati, S.K.R., J.T. Sylvester, L.E. Gilligan, and J.L. Firkins. 2006. Manipulation of fermentation profile and methane production with microbial inhibitors and protozoal retention in continuous culture. J. Dairy Sci. 89(Suppl. 1):127-128. Linke, P. L., A. R. Hippen, K. F. Kalscheur, D. J. Schingoethe 2006. Glycerol from soy diesel production as a feed supplement to lactating dairy cows. J. Dairy Sci. 89:1872 (abstr). Loor, J. J., L. Piperova, R. E. Everts, S. L. Rodriguez-Zas, J. K. Drackley, R. A. Erdman, and H. A. Lewin. 2005. Mammary gene expression profiling in cows fed a milk-fat depressing diet using a bovine 13,000 oligonucleotide microarray. J. Dairy Sci. 88(Suppl. 1):120. Markantonatos, X., Y. Aharoni, T. Cassidy, R. K. McGuffey, L. F. Richardson, and G. A.Varga. 2006. A simulation model to integrate ruminal Volatile Fatty Acids (VFA) and blood glucose metabolism in transition dairy cows under steady state conditions. J. Dairy Sci. 89:72. Mpapho, G. S., A. R. Hippen, K. F. Kalscheur, D. J. Schingoethe 2006. Lactational performance of dairy cows fed wet corn distillers grains for the entire lactation. J. Dairy Sci. 89 (Suppl 1):1871 (abstr). Nester, P.L., J W. Schroeder, K.A. Vonnahme, M.L. Bauer, W.L. Keller, D. E. Schimek. Altering milk production and composition of early lactation dairy cows fed flax seed. J. Dairy Sci. (Abstr.). Oelker, E.R., C. Reveneau, and J.L. Firkins. 2006. Effects of molasses and monensin in alfalfa hay or corn silage diets on rumen fermentation, total digestibility and milk production in Holstein cows. J. Dairy Sci. 89(Suppl.1):127. Osman, M.A., N.A. Mehyar, G. Bobe, J.F. Coetzee, D.C. Beitz, and K. Koehler. 2006. Acute effects of subcutaneous injections of glucagon and/or oral administration of glycerol on blood metabolites and hormones of dairy cows affected with fatty liver disease. J. Anim. Sci. 84(Suppl. 1)/J. Dairy Sci. 89(Suppl. 1):266. Petersen, A.B., Baldwin, R., VI, Bequette, B.J., and Kohn, R.A. (2006) Effect of ruminally degraded protein source on microbial protein flow in Holstein cows. J. Dairy Sci. 89 (Suppl. 1): p.142. Riasi, A., M.D. Stern, M. Danesh Mesgaran, M.J. Ruiz Moreno. 2005. Ruminal and post ruminal crude protein digestion of halophyte forages (Kochia scoparia, Atriplex domorphostegia) determined by various procedures. J. Dairy Sci. (Suppl. 1) 88:383. Stern, M. D., M. R. Moreno, M. O. Tapia, M. J. Murphy, G. I. Crawford and K. Nelsen. 2006. Studies using continuous culture fermenters and a three-step in situ/in vitro procedure to estimate protein metabolism in ruminants Stern, M.D. T. K. Miller-Webster, W. H. Hoover, M. Ruiz Moreno, C. A. Macgregor. 2005. Effects of soy gum application to soybean meal on protein degradation by ruminal microbes and intestinal protein digestion. J. Animal Sci. (Suppl. 1) 83:90. Stern, M.D., M.R. Moreno and C.A. Macgregor. 2005. Effects of various methods used to process soybean meal on protein digestion in the rumen and small intestine. 2005 Conference on Gastrointestinal Function, Chicago, IL. Volume 2:24. Thomas, M., A. R. Hippen, K. F. Kalscheur, D. J. Schingoethe 2006. Growth and performance of Holstein dairy calves fed distillers grains. J. Dairy Sci. 89 (Suppl 1):1864 (abstr). Thomas, M., A. R. Hippen, K. F. Kalscheur, D. J. Schingoethe 2006. Ruminal development in Holstein dairy calves fed distillers grains. J. Dairy Sci. 89 (Suppl 1):437 (abstr). Ungerfeld, E., Bequette, B.J., Owens, S.L., & Kohn, R. (2005) Measurement of volatile fatty acid interconversion as a means to study the role of thermodynamics in the control of fermentation. J. Dairy Sci. (Suppl. 1) Van Saun, R. J., A. Todd, G.A. Varga. 2005. Serum Mineral Concentrations and Risk of Periparturient Disease. Amer. Assoc. Bov. Pract. Williams, E.L., S. Rodriguez, D.C. Beitz, and S.S. Donkin. 2005. Effects of short-term glucagon administration on gluconeogenic enzymes in the liver of mid-lactation dairy cows. J. Dairy Sci. 88 (Suppl. 1)/J. Anim. Sci. 83 (Suppl. 1):79. Theses and Dissertations El-Kadi, S.W. 2006. REGULATION OF MACRONUTRIENT METABOLISM BY THE GASTROINTESTINAL TRACT OF RUMINANTS. PhD dissertation. University of Maryland, pp. 152. Thomas, M. 2006. Growth, rumen development, and metabolism of holstein calves fed distillers grains. M.S. Thesis, South Dakota State University, Brookings, 80 pp.

Prepared by A. R. Hippen at South Dakota State University (arnold.hippen@sdstate.edu)