Inaugural ASAS–CAAV Asia Pacif ic Rim Conference Abstracts

Advances in Digestive Physiology Metabolism and Health46 Maternal and offspring intestinal responses to gestationalnutrition in the ruminant: Growth, vascularity, and angiogenic factorexpression. A. M. Meyer* 1 , D. A. Redmer 1 , J. M. Wallace 2 , K. A. Vonnahme 1 ,L. P. Reynolds 1 , B. W. Hess 3 , and J. S. Caton 1 , 1 Center for Nutrition andPregnancy, Department of Animal Sciences, North Dakota State University,Fargo, ND, USA, 2 Rowett Institute of Nutrition and Health, University ofAberdeen, Bucksburn, Aberdeen, UK, 3 Department of Animal Sciences,Laramie, WY, USA.Small intestinal growth, development, and vascularization are often-overlookedbut essential processes driving nutrient uptake and expenditure, immunologicalcompetence, neonatal survival, postnatal growth, and metabolic regulationvia a cadre of hormones and growth factors. Tissue vascularization is crucialfor nutrient transport both to and from the intestine; thus, angiogenesis, or theformation of blood vessels, is critical for proper intestinal function. Maternalintestinal mass, cellularity, proliferation, and vascularity are responsive tophysiological states such as pregnancy and lactation. Additionally, intestinaldevelopment during the perinatal period includes growth via cell proliferation,hypertrophy, and increased vascularization. Restricted and excessive nutrientintake during gestation effect maternal intestinal mass, proliferation, cell size,and vascularity, although these responses are affected by diet composition,stage of gestation, age, and species of the dam. Changes in intestinal mass andblood flow alter both the nutrient needs and nutrient uptake potential by thedam, suggesting possible mechanisms by which the maternal system meets thedemands of gestation and lactation while also partially explaining differencesobserved in fetal development and postnatal performance. Fetal intestinal growthand vascularity have been decreased or increased by altered maternal nutritionin various studies. In some cases the effects of maternal gestational nutritionon the offspring small intestine appear to persist even when offspring receivesimilar postnatal management. Nutritional effects on intestinal vascularityhave been accompanied by changes in messenger RNA expression of vascularendothelial growth factor (VEGF), its receptors, endothelial nitric oxide (NO)synthesis, and soluble guanylate cyclase (NO receptor), implying possibleregulatory roles of VEGF and NO in these responses. Nutritional modulationor other therapeutics may provide means to stimulate intestinal blood flow orangiogenesis or both, affording potential opportunity to overcome growth orhealth challenges in ruminants.Key Words: angiogenesis, intestine, ruminant47 Application of new advances in digestive physiology as theyapply to swine nutrition. J. S. Radcliffe*, Purdue University, West Lafayette,IN.Advances in our knowledge of nutrition and digestive physiology are beingaided by an increasing array of molecular biology techniques. This allowsfor a fundamental understanding of various processes that may impact ourunderstanding of how pigs should be fed. However, at times there is a largedisconnect between basic research findings and their application on the farm.This talk will focus on recent, basic research findings and their potentialapplication to swine nutrition. In particular the talk will focus on recentdevelopments in our understanding of nutrient absorption and regulation, andhow this information may be used in the future to more accurately feed swine.Key Words: digestive physiology, nutrition48 In vivo and in vitro immunomodulation by mannanoligosaccharides in pigs. T. M. Che* and J. E. Pettigrew, Department ofAnimal Sciences, University of Illinois, Urbana-Champaign, IL, USA.Mannan oligosaccharides (MOS), derived from the cell wall of yeastSaccharomyces cerevisiae, has been shown to affect innate and humoralimmunity in animals. The MOS enhances phagocytosis by murine phagocytesand reduces the intensity of the wattle hypersensitivity reaction in pullets.Feeding MOS to animals increases the immunoglobulin levels in plasma, bile,and colostrum. These findings suggest that MOS potentially have the abilityto affect cytokine secretion by stimulated macrophages and to modulate theimmune response of animals against surrounding immunological challenges.Recent discovery reveals that MOS may enhance the immune response viaactivation of cytokine release but prevent overstimulation of the pig’s immunesystem. The MOS can activate porcine alveolar macrophages to secrete tumornecrosis factor-α (TNF-α). However, MOS, when fed to pigs or appliedin vitro, alleviates the inflammatory response of alveolar macrophages byreducing TNF-α and increasing IL-10. Further, immunomodulatory functionsof MOS have been proved in a porcine reproductive and respiratory syndromevirus (PRRSV) challenge study. As we know, PRRSV strongly modulates thehost's immune responses through reducing the total and differential leukocytecounts, inducing a variety of cytokines and delaying cell-mediated immunity.Dietary MOS is associated with rapidly increased numbers of total white bloodcells, lymphocytes, and neutrophils in PRRSV-infected pigs at the early stage ofinfection. Infected pigs fed MOS have a lowered fever, reduced serum TNF-α,and increased serum IL-10. Additionally, the data analysis from the AffymetrixGeneChip Porcine Genome Array indicates that MOS changes the expressionof thousands of genes caused by PRRSV in peripheral blood mononuclear cellsand bronchoalveolar lavage fluid cells. Briefly, modulation of the immunestatus of pigs via dietary MOS may promisingly bring favorable effects andprovide a novel prospect in improving pig health and production, but furtherresearch is still needed.Key Words: immunomodulation, mannan oligosaccharides, pigs49 A comparative study of three diagnostic techniques(FIRSTtest, polymerase chain reaction, and enzyme-linked immunosorbentassay) for detecting porcine ileitis on a pig farm. D. J. Yu 2 , C. K. Mah* 1 ,X. H. Li 1 , and B. Yin 2 , 1 Elanco Animal Health, Shanghai, China, 2 College ofAnimal Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian,China.The main objective of this cross-sectional study was to compare and evaluatethree different diagnostic techniques, namely FIRSTtest, PCR, and ELISA,used in detecting ileitis infection status in a pig farm. A total of 120 pigs with15 pigs in each different age group (3, 6, 9, 12, 15, 18, 21, and 24 wk of age)were randomly tested. The results showed that tool pigs from 9 to 12 wk of agehad a higher positive rate of ileitis tested with FIRSTtest and PCR diagnostictechniques. In this study, FIRSTtest was found to be more sensitive thanPCR in detecting Lawsonia intracellularis antigen in porcine fecal samples.The positive samples tested with FIRSTtest and PCR showed a significantcorrelation with the soft tool samples from the ileitis-suspected pigs. FIRSTtesttechnique was also found to be valid because it had good correlation with theserology findings. Trends of positive rate for porcine ileitis tested with ELISAmethod lagged behind those tested by FIRSTtest and PCR by as much as 4wk. The study findings indicated that FIRSTtest, being a recently developedqualitative test, is a quick, reliable, and easy-to-use test kit to detect porcineileitis on the farm site.Key Words: porcine ileitis, FIRSTtest, comparative study50 Pig personality, obesity and metabolic programming. R.Zhao*, X. Yang, D. Xia, L. Li, S. Wei, and Q. Sun, Nanjing AgriculturalUniversity, Nanjing, China.Different breed of pigs differ in personality, growth rate and carcass quality,yetthe mechanism underlying the formation and integration of the breed-specifictraits is elusive. In the present study, Chinese Erhualian (EHL) and EuropeanPietrain (PIE) pigs were subjected to a coping characteristic test, Backtest, at3, 10 and 17 days of age and a 2 hrs transport trial at the body weight of 20kg. We observed distinct breed differences not only in growth and obesity, butalso in stress-coping styles. EHL pigs demonstrated higher stress resistancecompared to PIE pigs, which was associated with 2-fold higher basal plasmacortisol concentration yet lower cortisol increase responding to stress. Higheradrenocortical steroidogenic capacity, characterised by enhanced ACTHsignaling and augmented expression of StAR and steroidogenic enzymes, mayresult in higher basal cortisol level, whereas higher expression of GR, MR,11βHSD1, but lower 11β-HSD2 in hippocampus may account for higher stresstolerance in EHL pigs owing to a more effective negative feedback regulationof HPA axis activity. GR expression was found to be breed-specific in otherperipheral tissues including liver, muscle and fat, which is associated withbreed-specific properties in hepatic gluconeogenesis, muscle energy metabolisnand fat deposition. To test the hypothesis that the breed-specific phenotypes andpattern of GR expression in EHL pigs is a result of natural selection under the17