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Abstract Background Carcass fatness is an important trait in most pig breeding programs. Following market requests, breeding plans for fresh pork consumption are usually designed to reduce carcass fat content and increase lean meat deposition. However, the Italian pig industry is mainly devoted to the production of Protected Designation of Origin dry cured hams: pigs are slaughtered at around 160 kg of live weight and the breeding goal aims at maintaining fat coverage, measured as backfat thickness to avoid excessive desiccation of the hams. This objective has shaped the genetic pool of Italian heavy pig breeds for a few decades. In this study we applied a selective genotyping approach within a population of ~ 12,000 performance tested Italian Large White pigs. Within this population, we selectively genotyped 304 pigs with extreme and divergent backfat thickness estimated breeding value by the Illumina PorcineSNP60 BeadChip and performed a genome wide association study to identify loci associated to this trait. Results We identified 4 single nucleotide polymorphisms with P≤5.0E-07 and additional 119 ones with 5.0E-07 Conclusions Further investigations are needed to evaluate the effects of the identified single nucleotide polymorphisms associated with backfat thickness on other traits as a pre-requisite for practical applications in breeding programs. Reported results could improve our understanding of the biology of fat metabolism and deposition that could also be relevant for other mammalian species including humans, confirming the role of neuronal genes on obesity.

Abstract Background In the domestic rabbit (Oryctolagus cuniculus), classical genetic studies have identified five alleles at the Extension locus: ED (dominant black), ES (steel, weaker version of ED), E (wild type, normal extension of black), eJ(Japanese brindling, mosaic distribution of black and yellow) and e (non-extension of black, yellow/red with white belly). Sequencing almost the complete coding sequence (CDS) of the rabbit MC1R gene, we recently identified two in-frame deletions associated with dominant black (c.280_285del6; alleles ED or ES) and recessive red (c.304_333del30; allele e) coat colours. It remained to characterize the eJallele whose phenotypic effect is similar to the Orange and Sex-linked yellow loci of cat and Syrian hamster. Results We sequenced the whole CDS in 25 rabbits of different coat colours including 10 Japanese and 10 Rhinelander (tricolour) rabbits and identified another 6 bp-in frame deletion flanked by a G > A transition in 5' (c.[124G>A;125_130del6]) that was present in all animals with Japanese brindling coat colour and pattern. These mutations eliminate two amino acids in the first transmembrane domain and, in addition, cause an amino acid substitution at position 44 of the wild type sequence. Genotyping 371 rabbits of 31 breeds with different coat colour this allele (eJ) was present in homozygous state in Japanese, Rhinelander and Dutch tricolour rabbits only (except one albino rabbit). Rabbits with eJ/eJ genotype were non fixed at the non-agouti mutation we previously identified in the ASIP gene. Segregation in F1 and F2 families confirmed the order of dominance already determined by classical genetic experiments with a possible dose effect evident comparing eJ/eJ and eJ/e animals. MC1R mRNA was expressed in black hair skin regions only. Conclusions The c.[124A;125_130del6] allele may be responsible for a MC1R variant determining eumelanin production in the black areas. However, the mechanism determining the presence of both red and black hairs in the same animal seems more complex. Expression analyses of the c.[124A;125_130del6] allele suggest that MC1R transcription may be regulated epigenetically in rabbits with the Japanese brindling phenotype. Further studies are needed to clarify this issue.

PRKAG3 is a major gene for meat quality and production in pigs. In this study, we investigated two single nucleotide polymorphisms (SNPs) of the PRKAG3 promoter region (g.-995A>G and g.-311A>G) in 381 pigs of different breeds. Association between these SNPs and three major haplotypes, constructed including other three substitutions (c.89C>A, c.154A>G and c.595G>A) and different traits (meat quality parameters: pH 2h , pH u , glycogen and lactate content, glycolytic potential and cathepsin B activity of Semimembranosus muscle; estimated breeding values and random residuals for growth performances and carcass traits) were analysed in 271 Italian Large White performance tested pigs. A significant effect ( P = 0.043) of the g.-995A>G SNP on cathepsin B activity and a suggestive effect ( P = 0.067) of the g.-311A>G SNP on pH u were found. The haplotype [g.-995G:g.-311G:c.89A:c.154G:c.595G] was associated with pH u ( P = 0.024), glycolytic potential ( P = 0.040) and cathepsin B activity ( P = 0.086). This study on haplotypes, including promoter region SNPs, contribute to explain the effect of this gene on meat quality traits in pigs. [ABSTRACT FROM AUTHOR]

This working proposal aims to establish an Internal Medicine Network (IMN) model for the appropriate management of the poly-pathological complex patient in the different phases of his illness natural hystory. The IMN is based on an organization recalling the Hub and Spoke system already used for existing specialized networks. The Internal Medicine Unit (IMU) is the natural destination of acutely ill patients suffering from systemic or multi-organ diseases. Three are the IMU specific tasks: i) to stabilize acute, severe, poly-pathologic and complex patients; ii) to develop difficult etiological diagnosis in these patients and in those who should necessarily be admitted to the hospital, not being possible, for different reasons, alternative routes; iii) to select the acute poly-pathological complex patient's priorities. The expected results of a new model of integration system inside the IMN are: i) reduction and rationalization of expenditure in the medical area, increasing effectiveness, quality and safety guaranteeing patient centrality; ii) patients stratification based on characteristics of gravity, acute illness, estimated duration of hospitalization; iii) reduction of inappropriate hospital admissions ensuring connections between hospital and primary care units; iv) definition of different care pathways for patients hospitalized due to non-communicable diseases; v) implementation of new common medical records. The public-private partnership inside the IMN could be able to increase appropriateness reducing health costs. Patient-centered problems assessment, together with integration, cooperation, coordination and effective communication are some simple rules useful to achieve tangible results in a complex system and the IMN model represents its practical application. [ABSTRACT FROM AUTHOR]

A shortcut to identify DNA markers associated with economic traits is to use a candidate gene approach that is still useful in livestock species in which molecular tools and resources are not advanced or not well developed. Mutations in the growth hormone receptor (GHR) gene associated with production traits have been already described in several livestock species. For this reasonGHRcould be an interesting candidate gene in the rabbit. In this study we re-sequenced all exons and non-coding regions of the rabbitGHRgene in a panel of 10 different rabbits and identified 10 single nucleotide polymorphisms (SNPs). One of them (g.63453192C>G or c.106C>G), located in exon 3 was a missense mutation (p.L36V) substituting an amino acid in a highly conserved position across all mammals. This mutation was genotyped in 297 performance tested rabbits of a meat male line and association analysis showed that the investigated SNP was associated with weight at 70 days (P < 0.05). The most frequent genotype (GG) was in animals with higher weight at this age, suggesting that the high directional selection pressure toward this trait since the constitution of the genotyped line might have contributed to shape allele frequencies at this polymorphic site. [ABSTRACT FROM AUTHOR]

The hospital internal medicine (IM) needs to adapt to the socio-demographic changes occurred during the last thirty years: patients currently show an increased overall complexity owing to the increase in the average age of the patients admitted, to more several and severe comorbidities, and a higher concentration in our wards of most severe cases. Our departments have to change in order to pursue a more efficient organization and to offer care to users modulated according to their needs and conditions. The Intensity of Care in Internal Medicine Group of the Federation of Associations of Hospital Doctors on Internal Medicine - Lazio carried out a population-based study in eight Internal Medicine wards of the region with the aim of characterizing the patients there admitted, using the modified early warning score (mEWS), monitoring and evaluating the outcomes of hospitalization. This has allowed us to determine the cut-off of the score indicating a greater statistical probability of a fatal outcome corresponding to 3, contrary to what originally reported by Subbe et al. in 2001. According to our results into the Departments of IM should be provided an area of high care, where monitor and stabilize the patients admitted with a mEWS score ≥ 3, before transferring them to the wards of lower intensity of care. This organizational model of the high care of medical patients has the benefit of offer the technical and professional assistance appropriate to the level of clinical risk, with more intensive care to more critical stages of illness. [ABSTRACT FROM AUTHOR]

TheGPR120gene (also known asFFAR4orO3FAR1) encodes for a functional omega-3 fatty acid receptor/sensor that mediates potent insulin sensitizing effects by repressing macrophage-induced tissue inflammation. For its functional role,GPR120could be considered a potential target gene in animal nutrigenetics. In this work we resequenced the porcineGPR120gene by high throughput Ion Torrent semiconductor sequencing of amplified fragments obtained from 8 DNA pools derived, on the whole, from 153 pigs of different breeds/populations (two Italian Large White pools, Italian Duroc, Italian Landrace, Casertana, Pietrain, Meishan, and wild boars). Three single nucleotide polymorphisms (SNPs), two synonymous substitutions and one in the putative 3′-untranslated region (g.114765469C > T), were identified and their allele frequencies were estimated by sequencing reads count. The g.114765469C > T SNP was also genotyped by PCR-RFLP confirming estimated frequency in Italian Large White pools. Then, this SNP was analyzed in two Italian Large White cohorts using a selective genotyping approach based on extreme and divergent pigs for back fat thickness (BFT) estimated breeding value (EBV) and average daily gain (ADG) EBV. Significant differences of allele and genotype frequencies distribution was observed between the extreme ADG-EBV groups (P < 0.001) whereas this marker was not associated with BFT-EBV. [ABSTRACT FROM AUTHOR]

The English spotting coat color locus in rabbits, also known as Dominant white spotting locus, is determined by an incompletely dominant allele (En). Rabbits homozygous for the recessive wild-type allele (en/en) are self-colored, heterozygous En/en rabbits are normally spotted, and homozygous En/En animals are almost completely white. Compared to vital en/en and En/en rabbits, En/En animals are subvital because of a dilated (“mega”) cecum and ascending colon. In this study, we investigated the role of the KIT gene as a candidate for the English spotting locus in Checkered Giant rabbits and characterized the abnormalities affecting enteric neurons and c-kit positive interstitial cells of Cajal (ICC) in the megacolon of En/En rabbits. Twenty-one litters were obtained by crossing three Checkered Giant bucks (En/en) with nine Checkered Giant (En/en) and two en/en does, producing a total of 138 F1 and backcrossed rabbits. Resequencing all coding exons and portions of non-coding regions of the KIT gene in 28 rabbits of different breeds identified 98 polymorphisms. A single nucleotide polymorphism genotyped in all F1 families showed complete cosegregation with the English spotting coat color phenotype (θ = 0.00 LOD  = 75.56). KIT gene expression in cecum and colon specimens of En/En (pathological) rabbits was 5–10% of that of en/en (control) rabbits. En/En rabbits showed reduced and altered c-kit immunolabelled ICC compared to en/en controls. Morphometric data on whole mounts of the ascending colon showed a significant decrease of HuC/D (P<0.05) and substance P (P<0.01) immunoreactive neurons in En/En vs. en/en. Electron microscopy analysis showed neuronal and ICC abnormalities in En/En tissues. The En/En rabbit model shows neuro-ICC changes reminiscent of the human non-aganglionic megacolon. This rabbit model may provide a better understanding of the molecular abnormalities underlying conditions associated with non-aganglionic megacolon. [ABSTRACT FROM AUTHOR]

A 291 bp short interspersed nuclear element (SINE) insertion in the porcine vertnin (VRTN) gene on porcine chromosome 7 was shown to affect vertebral number and several production traits: allele Q (with the insertion) increases vertebral number compared to the wild type allele (WT, without insertion). In this study we genotyped this polymorphism in eight pig breeds (Italian Large White, Italian Duroc, Italian Landrace, Cinta Senese, Mora Romagnola, Casertana, Apulo Calabrese, and Nero Siciliano) and in Italian wild boars to evaluate allele frequency distribution of the two alleles. Allele Q was the most frequent in Italian Landrace and Italian Duroc (0.738 and 0.545, respectively) whereas it was the less frequent in all other breeds and was absent in wild boars. Association study was carried out in two Italian Large White samples. These two groups of animals were constituted by performance tested pigs for which estimated breeding values (EBV) and random residuals (RR) for several traits (average daily gain, back fat thickness, feed:gain ratio, lean cuts and ham weight) were calculated: i) 270 pigs chosen without any criteria (random group), that were also measured for several meat quality traits; ii) 560 gilts with extreme and divergent EBV for back fat thickness. For these animals vertebral number was not available. Results of the association analyses indicated that allele Q was associated with a lower ham weight, confirming indirectly, the negative correlation reported by other studies between vertebral number and this trait. No other trait was associated with the analysed VRTN polymorphism. [ABSTRACT FROM AUTHOR]

In this study we resequenced 1729 bp of the rabbit melanocortin 4 receptor (MC4 R) gene in 31 rabbits from different breeds/lines and identified ten polymorphisms: one was an indel and 9 were single nucleotide polymorphisms (SNPs). The indel and 5 SNPs were in the 5′-flanking region, 3 were synonymous SNPs and one was a missense mutation (c.101G>A; p.G34D), located in a conserved position of the extracellular tail of the MC4 R protein. The missense mutation was analyzed in a panel of 74 rabbits of different breeds and in 516 performance tested rabbits of a commercial paternal line under selection for growth efficiency. Association analysis indicated that rabbits with the less frequent genotype in this population (DD) had a lighter weight at 70 postnatal days than animals with genotype GD (P < 0.10) and animals with genotype GG (P < 0.05). This is the third study on candidate genes, after those on GH1 and IGF2 that reported a marker associated with finishing weight. Therefore, it seems that a candidate gene approach in rabbit based on previous information accumulated in other livestock species could be useful to identify genes explaining a fraction of variability of performance traits with potential application on rabbit breeding and selection. [ABSTRACT FROM AUTHOR]

The aim of the paper is to identify the role of the hospital Internal Medicine specialist in the Internal Medicine Unit (IMU) through a clinical and statistical analysis of the patients referred to them by identifying the activities that differentiate them from patients in General Medicine and Emergency Departments, i.e. diagnosis and treatment of complex patient with varying degrees of instability, identifying priorities in the acute problems of co-morbidities. The modified early warning score (MEWS), an internationally validated marker, was chosen to assess and stratify the clinical instability of patients referred to the IMU. A literature review was carried out, and a cut-off score of 3 was chosen to define the critical patients referred to the IMU; a MEWS value of 4 defines the need for transfer to the Intensive Care Unit (ICU) or Intensive Cardiac Care Unit (CCU), considered the primary end point in most of the studies examined. To better characterize the internist’s role today, a strength, weaknesses, opportunity, threats (SWOT) analysis was performed and examined, and commented upon. A total of 101 articles were reviewed and 5 were selected. The case histories relating to the IMU appear to be made up of complex patients with conditions that are, in most cases, acute and unstable. From 10% to 17% of patients present a MEWS of 3 or more that defines a condition of severe clinical instability requiring continuous observation and non-invasive multi-parametric monitoring. From 5% to 7% of cases present a MEWS of 4 or more and therefore require transfer to the ICU/CCU or risk rapid death. Approximately 40% of patients present MEWS of 1-2 and still have disease flare-up, but with a lesser degree of instability; however, these patients could experience a potentially negative disease development if not promptly and properly treated. Approximately 40% of patients have MEWS of 0 and represent the group of fragile patients that cannot be studied, diagnosed or stabilized on an outpatient basis. The critical analysis of the literature review and the SWOT analysis suggest that the two specific hospital internist’s tasks are: i) to stabilize acute, severe and complex patients with multiple pathologies; and ii) to develop etiologically difficult diagnoses in these and in fragile patients who need to be admitted to the hospital because the alternative diagnostic routes, for various reasons, cannot be used. [ABSTRACT FROM AUTHOR]

A few studies have shown that a microsatellite at intron 1 of the insulin-like growth factor 1 (IGF1) gene is associated with several production traits in a few pig populations. In the current work we evaluated associations between this microsatellite and production traits in Italian Large White and Italian Duroc pigs. Association studies were carried out on a total of 1120 animals using two experimental designs: i) a selective genotyping approach based on extreme and divergent Italian Large White pigs for back fat thickness (BFT) estimated breeding value (EBV) or on extreme and divergent Italian Duroc pigs for visible intermuscular fat (VIF) EBV; and ii) analysis of unselected pigs (random groups) coming from populations of the two breeds. Allele distributions between Italian Large White and Italian Duroc pigs were different (P<0.05) with longer alleles being more frequent in Italian Large White. Results of the association analyses from two different random groups showed that this marker affects average daily gain EBV, lean cut EBV and BFT EBV in Italian Large White and BFT EBV in Italian Duroc (P<0.05). Association analysis carried out with random residuals confirmed, to some extent (P=0.096), the effects on BFT in the same animals. However, this result was not confirmed in the two extreme and divergent Italian Large White groups used in the selective genotyping experexperiment. These inconsistent results may indicate that the effect of the IGF1 microsatellite is doubtful in the investigated finishing pigs. [ABSTRACT FROM AUTHOR]

Several studies have shown that porcine chromosome 2 (SSC2) harbors important quantitative trait loci (QTL) for production traits. In particular, an imprinted QTL for muscle mass production is determined by a mutation in the IGF2 gene (intron3-g.3072G>A). We recently identified and analysed single nucleotide polymorphisms (SNPs) in genes (cathepsin D, CTSD g.70G>A; cathepsin F, CTSF g.22G>C; lactate dehydrogenase A, LDHA g.46G>T) localized on SSC2 (including the IGF2 intron3-g.3072G>A SNP) showing association with production traits in Italian Large White pigs and/or localizing them on QTL regions. Here we analysed these markers applying a selective genotyping approach based on estimated breeding values (EBVs). Three groups of Italian Large White pigs each made by animals with the most positive (n. 50) and most negative (n. 50) EBVs for average daily gain (ADG), backfat thickness (BFT) or weight of lean cuts (LC) and one group of Italian Duroc pigs made by 50 animals with most positive and 50 animals with most negative EBV for visible intermuscular fat (VIF) were genotyped. In Italian Large White pigs, allele frequency differences for the IGF2 intron3-g.3072G>A SNP between the two extreme tails for all groups were highly significant (considering all analysed animals: P=9.53E-20 for LC; P=3.16E-15 for BFT; P=4.41E-6 for ADG). Significant allele frequency differences were also observed for the CTSD g.70G>A (P=0.0002 for ADG; P=0.00068) and LDHA g.46G>T (P=2.32E-5 for ADG) polymorphisms. These results provide further support on the effects of these polymorphisms or genes whose application on marker assisted selection programs could be envisaged. [ABSTRACT FROM AUTHOR]

The identification of the breed of origin of farm animals has recently assumed particular relevance, since increasing interests in marketing mono-breed labelled lines of beef and dairy products have in fact created the need to protect them from frauds. In order to develop DNA based breed traceability and authentication protocols, the first step is the identification of breed specific markers with high discriminatory power among breeds. We analysed two single nucleotide polymorphisms (SNP) identified in exon 2 (g.72779776C>T) and exon 3 (g.72783182A>G) of the KIT gene (a candidate gene for the spotting locus) in seven cattle breeds with different coat colour patterns (Italian Holstein-Friesian, no. = 61; Italian Brown, no. = 60; Italian Simmental, no. = 78; Jersey, no. = 60; Rendena, no. = 51; Reggiana, no. = 128; and Modenese, no. = 52). The two alleles of both SNPs were detected in all analysed breeds making their use unsuitable in breed traceabilty with a deterministic approach. Italian Simmental was almost fixed for the most common alleles (g.72779776C and g.72783182A). Haplotype analysis showed that spotted breeds (Italian Holstein-Friesian and Italian Simmental) had only two haplotypes, of which one ([C:A]) with high frequency (90% and 99%, respectively). Analysis of molecular variance (AMOVA) averaged over the two markers indicated that genetic variation between spotted and non-spotted groups of breeds amounted to 25.3% (P<0.05), supporting a possible involvement of the KIT gene in influencing the spotted phenotype, but probably not determining it, as we previously suggested. Pairwise Fst values indicated significant differences among almost all pair of investigated breeds. The high discriminatory power of the analysed SNPs is an important characteristic for the inclusion of these markers in SNP panels useful for breed allocation and traceability based on probabilistic approaches. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the allele frequency distribution at the DGAT1 p.K232A polymorphic site in seven Italian dairy and dual purpose cattle breeds. On the whole, 651 animals belonging to Italian Holstein (116), Italian Brown (105), Italian Simmental (95), Valdostana Red Pied (95), Rendena (62), Reggiana (128) and Modenese (50) breeds were genotyped by PCR-RFLP. Sequencing was carried out to confirm results of the genotyping protocol. The DGAT1 p.232K allele was identified in Italian Holstein (25.4%), Reggiana (17.2%), and with very low frequency in Italian Simmental, Valdostana Red Pied and Rendena (<1%). In Italian Brown and Modenese, this allele was not detected. These results indicated that this polymorphic site can be considered for association studies only in Italian Holstein and Reggiana breeds. Deviation from Hardy- Weinberg equilibrium was observed in the Reggiana breed (P<0.01) in which there was an excess of heterozygous sires and absence of animals with the p.232KK genotype. This result should be further evaluated because the analysed sires represented almost all bulls available for artificial insemination in this breed. Comparison of allele frequencies at the DGAT1 locus with several other Holstein populations showed a wide range of variability, probably due to different selection strategies adopted. [ABSTRACT FROM AUTHOR]

Background: In the domestic rabbit (Oryctolagus cuniculus), classical genetic studies have identified five alleles at the Extension locus: ED (dominant black), ES (steel, weaker version of ED), E (wild type, normal extension of black), ... (Japanese brindling, mosaic distribution of black and yellow) and e (non-extension of black, yellow/red with white belly). Sequencing almost the complete coding sequence (CDS) of the rabbit MC1R gene, we recently identified two in-frame deletions associated with dominant black (c.280_285del6; alleles ED or ES) and recessive red (c.304_333del30; allele e) coat colours. It remained to characterize the ... allele whose phenotypic effect is similar to the Orange and Sex-linked yellow loci of cat and Syrian hamster. Results: We sequenced the whole CDS in 25 rabbits of different coat colours including 10 Japanese and 10 Rhinelander (tricolour) rabbits and identified another 6 bp-in frame deletion flanked by a G > A transition in 5' (c. [124G>A;125_130del6]) that was present in all animals with Japanese brindling coat colour and pattern. These mutations eliminate two amino acids in the first transmembrane domain and, in addition, cause an amino acid substitution at position 44 of the wild type sequence. Genotyping 371 rabbits of 31 breeds with different coat colour this allele (...) was present in homozygous state in Japanese, Rhinelander and Dutch tricolour rabbits only (except one albino rabbit). Rabbits with .../... genotype were non fixed at the non-agouti mutation we previously identified in the ASIP gene. Segregation in F1 and F2 families confirmed the order of dominance already determined by classical genetic experiments with a possible dose effect evident comparing .../... and .../e animals. MC1R mRNA was expressed in black hair skin regions only. Conclusions: The c.[124A;125_130del6] allele may be responsible for a MC1R variant determining eumelanin production in the black areas. However, the mechanism determining the presence of both red and black hairs in the same animal seems more complex. Expression analyses of the c.[124A;125_130del6] allele suggest that MC1R transcription may be regulated epigenetically in rabbits with the Japanese brindling phenotype. Further studies are needed to clarify this issue. [ABSTRACT FROM AUTHOR]

The English spotting coat color locus in rabbits, also known as Dominant white spotting locus, is determined by an incompletely dominant allele (En). Rabbits homozygous for the recessive wild-type allele (en/en) are self-colored, heterozygous En/en rabbits are normally spotted, and homozygous En/En animals are almost completely white. Compared to vital en/en and En/en rabbits, En/En animals are subvital because of a dilated (“mega”) cecum and ascending colon. In this study, we investigated the role of the KIT gene as a candidate for the English spotting locus in Checkered Giant rabbits and characterized the abnormalities affecting enteric neurons and c-kit positive interstitial cells of Cajal (ICC) in the megacolon of En/En rabbits. Twenty-one litters were obtained by crossing three Checkered Giant bucks (En/en) with nine Checkered Giant (En/en) and two en/en does, producing a total of 138 F1 and backcrossed rabbits. Resequencing all coding exons and portions of non-coding regions of the KIT gene in 28 rabbits of different breeds identified 98 polymorphisms. A single nucleotide polymorphism genotyped in all F1 families showed complete cosegregation with the English spotting coat color phenotype (θ = 0.00 LOD  = 75.56). KIT gene expression in cecum and colon specimens of En/En (pathological) rabbits was 5–10% of that of en/en (control) rabbits. En/En rabbits showed reduced and altered c-kit immunolabelled ICC compared to en/en controls. Morphometric data on whole mounts of the ascending colon showed a significant decrease of HuC/D (P<0.05) and substance P (P<0.01) immunoreactive neurons in En/En vs. en/en. Electron microscopy analysis showed neuronal and ICC abnormalities in En/En tissues. The En/En rabbit model shows neuro-ICC changes reminiscent of the human non-aganglionic megacolon. This rabbit model may provide a better understanding of the molecular abnormalities underlying conditions associated with non-aganglionic megacolon. [ABSTRACT FROM AUTHOR]