Expression and cellular localization of monocarboxylate transporters (MCT2, MCT7, and MCT8) along the cattle gastrointestinal tract.

Fourteen members of the monocarboxylate transporter (MCT, SLC16) family have been identified, each having a different tissue distribution and substrate specificity. The expression of monocarboxylate transporters MCT1 and MCT4 have been studied in the gastrointestinal tract of ruminants; however, details of the expression of other MCT isoforms in the various parts of ruminant gastrointestinal tract are lacking. Reverse transcription with the polymerase chain reaction was used to study the regional distribution of MCT2, MCT3, and MCT5-MCT14 in the cattle gastrointestinal tract and verified the existence of MCT mRNA transcripts for MCT2, MCT3, MCT4, MCT7, MCT8, MCT9, MCT10, MCT13, and MCT14 in the ruminal and abomasal epithelia, mRNA transcripts for MCT2, MCT3, MCT4, MCT7, MCT8, MCT10, MCT13, and MCT14 in the jejunum, and mRNA transcripts for MCT2, MCT3, MCT4, MCT7, MCT8, MCT13, and MCT14 in the caecum of cattle. At the cellular level, immunohistochemical studies localized MCT2, MCT7, and MCT8 proteins in the cattle rumen, abomasum, jejunum, and caecum. This is the first study to detect the expression of various MCT isoforms in the gastrointestinal tract of a ruminant species. Our data suggest that these transporter proteins are involved in essential physiologic processes and are possible molecular targets for studying the regulation of the transport of short-chain monocarboxylates, aromatic amino acids, and thyroid hormones across the gastrointestinal tract of cattle.

Identification and Distribution of the Interstitial Cells of Cajal in the Abomasum of Goats.

The interstitial cells of Cajal (ICCs) are regarded as pacemakers and are involved in neurotransmission in the gastrointestinal tract (GIT) of animals. However, limited information is available about the existence of ICCs within the GIT of ruminants. In this study, we investigated the ultrastructural characteristics and distribution of ICCs in goat abomasum using transmission electron microscopy and c-kit immunohistochemistry. Two different kinds of c-kit immunoreactive cells were observed in the abomasum. The first was identified as ICCs, which appeared to be multipolar or bipolar in shape, with some processes. These c-kit immunoreactive cells were deposited in the submucosal layer, myenteric plexus between the circular and longitudinal muscle layers, and within the longitudinal and circular muscle layers of the abomasum. The second type of cell was round in shape and was identified as mast cells, which were located in the submucosal layer as well as in the lamina propria. Ultrastructurally, ICCs were also observed as stellate or spindle-shaped cells, which were consistent in shape with our c-kit immunoreactive cells. In the cytoplasm of ICCs, numerous mitochondria, rough endoplasmic reticulum, and caveolae were detected. ICCs were located in the myenteric plexus between the longitudinal and circular muscle layers (ICC-MY), with the longitudinal and circular muscle layer was replaced as "intramuscular layers" (ICC-IM), and in the submucosal layer (ICC-SM). In addition, we found ICCs surrounding nerve fibers and smooth muscle cells, where they formed heterocellular junctions in the form of close membrane associations or gap junctions and homocellular junctions among the processes of the ICCs. In the current study, we provide the first complete characterization of ICCs within the goat abomasum and propose that ICCs might have a key role in producing contractions in the ruminant stomach for proper absorption of nutrients.

Impact of aging on distribution of IgA+ and IgG+ cells in aggregated lymphoid nodules area in abomasum of Bactrian camels (Camelus bactrianus).

The aggregated lymphoid nodules area (ALNA) in the abomasum is a special organized lymphoid tissue discovered only in Bactrian camels at present. This study aimed to explore the impact of aging on distribution of IgA+ and IgG+ cells in ALNA in abomasum of Bactrian camels. Twenty-four Alashan Bactrian camels were divided into the following four age groups: young (1-2years), pubertal (3-5years), middle-aged (6-16years) and old (17-20years). IgA+ and IgG+ cells in the lamina propria of ALNA were observed and analyzed using immunohistochemical and statistical techniques. The results showed that, in ALNA, the distribution of IgA+ and IgG+ cells were diffuse, and only a few were in subepithelium dome (SED) and most of them in non-SED. Meanwhile, there were significantly more IgA+ cells than IgG+ cells in SED from the young to the middle aged group, but which reversed in old group (P<0.05). However, the aging significantly decreased the densities of IgA+ and IgG+ cells populations in non-SED (P<0.05); in SED, there were no significant differences between the densities of IgA+ and IgG+ cells, but which were both significantly lower in old group than those in young group (P<0.05). The results demonstrated that, in mucosal effector sites, the aging significantly decreased the densities of IgA+ and IgG+ cells populations and impacted on the defense barriers formed by IgA and IgG, but had no impact on the scattered characteristics. In inductive sites, the aging dramatically declined their densities, and they should have close relationships with immune memory. These findings lay the foundation for further researching the mucosal immune disorder or decline caused by aging, and especially underscore the importance of researching the impact of aging on the relationship between IgA+ and IgG+ cells populations and the microbiota colonized in abomasum of Bactrian camels.

Comparative analysis of the merino sheep and Iberian red deer abomasum during prenatal development.

The aim of this study is to describe differences in the ontogenesis of the abomasum in sheep (domestic ruminant) and deer (wild ruminant). Histomorphometric and immunohistochemical analysis were carried out on 50 embryos and fetuses of the sheep and 50 red deer from the first prenatal stages until birth. To compare similar periods of gestation in both species, we calculate the percentages of gestation. The appearance of the abomasum was earlier in the red deer (22% gestation) than in the sheep (25% gestation). Throughout development the epithelium happened sequentially, being of the types pseudostratified to simple cylindrical. This important modification was earlier in the red deer than the sheep. At 46% gestation in red deer and 50% in sheep, gastric pits were observed on the surface of abomasal folds. Our studies suggest a close link between the initial formation of these pseudoglandular structures and the clear separation of lamina propria and submucosa separated by de muscularis mucosae. At 54% gestation in red deer and at 60% in sheep, in the bottom of these pits the first outlines of glands were distinguishable. Finally, the presence of neuroendocrine and glial cells were detected in deer at earlier stages than in sheep.

Localization and secretion of epidermal growth factor in the parotid gland and its intragastric kinetics in sheep.

Ruminants secrete a large quantity of saliva that is rich in electrolytes; however, it remains unclear whether their parotid saliva contains epidermal growth factor (EGF). The present study was set up to examine the distribution of EGF and transforming growth factor-alpha (TGF-alpha) in the ovine parotid and submandibular glands and the salivary secretion of EGF-like binding activity (EGF-LBA) as the sum of EGF and TGF-alpha in conscious sheep. We also measured changes in the intragastric concentration of EGF-LBA in the ovine rumen and abomasum, and examined the effect of bilateral diversion of parotid saliva on intragastric EGF-LBA concentration in sheep. Both the ovine parotid and, to a lesser extent, the submandibular glands contained EGF-LBA. Immunohistochemical study showed that EGF and TGF-alpha-immunoreactivities were localized in the ductal epithelium in both glands. Transcriptional expression of EGF and TGF-alpha mRNA was demonstrated in both glands by reverse transcription-polymerase chain reaction (RT-PCR). In conscious sheep, the parotid gland continuously secreted EGF-LBA in the saliva before feeding, and the secretion of parotid EGF-LBA was markedly increased during feeding. After diversion of the parotid saliva for 1 week, EGF-LBA concentration in the ruminal fluid, but not in the abomasal fluid, decreased in the postprandial period, indicating that parotid EGF-LBA is a primary source of EGF-LBA for the rumen fluid during the postprandial period in sheep. Moreover, RT-PCR detected the expression of TGF-alpha mRNA in the rumen and abomasum and that of EGF in the abomasum, implying that these stomachs possibly supply, in part, EGF-LBA to the luminal fluid.

St. Croix sheep produce a rapid and greater cellular immune response contributing to reduced establishment of Haemonchus contortus.

The objective of this study was to determine breed differences in immune response shortly following Haemonchus contortus infection. Peripheral and local cellular and humoral immune responses were evaluated in 24 St. Croix hair lambs and 24 Dorset×(Finn-Rambouillet) wool lambs at 0, 3, 5 and 7 days after infection with 10,000 L3 H. contortus larvae. Blood samples taken immediately before harvest revealed no differences in circulating effector cell populations, yet there were significant differences in levels of circulating neutrophils. Across all time points, hair lambs had a higher average circulating neutrophil concentration (3018 cells/µl) than wool lambs (1818 cells/µl; P<0.05). Infected hair lambs also had greater serum total-IgA compared to wool lambs (1.8 vs 0.9 mg/ml; P=0.006). Breeds did not differ in eosinophil or globule leukocyte (GL) counts in abomasal tissue, but infiltration of these cell populations increased with time. Globule leukocyte counts peaked at day 3 after infection whereas eosinophil numbers continued to increase to day 7 after infection. When averaged across all time points, abomasal neutrophil counts were higher in hair lambs (831 cells/mm(2)), than wool lambs (561 cells/mm(2); P<0.0001). Total abomasal lymph node (ALN) weight increased exponentially from 2.60 g at day 0 to 6.57 g by day 7 in hair lambs whereas ALN weight only marginally increased in wool lambs and was significantly lower than hair lambs by day 7 (P=0.0003). This result suggests a greater expansion of lymphocytes in the ALN promoting early development of antigen-specific acquired immune responses in hair lambs. Greater IgA production and infiltration of immune cells to the abomasal mucosa at an earlier stage of infection may limit establishment of adult parasites and thereby shorten the duration and severity of infection.

Oxyntic cell differentiation during physiological cell renewal in abomasal mucosa of adult cattle.

The origin and differentiation of the oxyntic cell lineage during physiological cell renewal was investigated by light and electron microscopy in the abomasal mucosa of adult cattle. The morphologically heterogeneous oxyntic cell population exhibits various developmental subtypes depending on the position within the oxyntic unit. Pre-oxyntic cells of the isthmus and neck represent the immature precursors. Though heterogeneous with respect to the degree of canalicular and tubulovesicular membrane development, they all contain secretory granules resembling those of either isthmus cells, immature surface mucous cells, neck cells or young chief cells. A secretory granule-free stem cell is not present in the bovine. Downward to the gland base genesis of canalicular as well as tubulovesicular membranes is gradually completed; thus pre-oxyntic cells give rise to mature oxyntic cells. Older degenerative oxyntic cells, primarily located within the gland bottom, are characterized by progressive involution of canalicular and tubulovesicular membranes. Towards the pit, differentiation of pre-oxyntic cells is associated with atypical and incomplete development of canaliculi and tubulovesicles. In consequence, these superficial oxyntic cells have a reduced secretory capacity from a morphological point of view.

An immunohistochemical study on the development of progastricsin-immunoreactive cells in the bovine abomasal mucosa.

The development of progastricsin-immunoreactive cells in the abomasal mucosa of cattle fetuses was studied by immunohistochemistry. Progastricsin-immunoreactive cells were detected first in the fundic and pyloric regions of 52 cm in crown-rump length (CRL) fetuses (about 180 days of gestation). The frequency of occurrence of progastricsin-immunoreactive cells and the intensity of their immunoreactivity increased with the progress of gestation, but most of these immunoreactivities were restricted to the basal portion of the fundic and pyloric glands. After birth, in the fundic mucosa, progastricsin immunoreactivities were found not only in the chief cells but also in the surface mucous cells of the gastric pits. In the cow, the immunoreactivity of the surface mucous cells was even stronger than that of the chief cells. In the pyloric mucosa, progastricsin immunoreactivities were found in the gastric pits and in the basal portion of the pyloric glands, but they were organized in small groups and showed a patchy distribution in the basal portions.

Fine structure of developing gastric parietal cells in the bovine abomasum.

Developmental changes in the fine structure of gastric parietal cells were studied in bovine fetuses and neonates. Definitive parietal cells first appeared as non-granular light cells at five months of fetal age (in a 48 cm long fetus). At this age they had a microvillous apical surface and cytoplasmic vesicles which accumulated at the apex. Intracellular canaliculi appeared with an increase in mitochondria at six to seven months of fetal age. Fully differentiated parietal cells were present from the eighth month of gestation. At birth they were similar in appearance to those of the adult abomasum.

Antibody-containing cells in the abomasal mucosa of sheep with genetic resistance to Haemonchus contortus.

The frequency distribution of parasite-specific antibody-containing cells (ACC) and total immunoglobulin-containing cells (ICC) in the abomasal mucosa was examined in genetically resistant and random-bred sheep, following infection with Haemonchus contortus, to determine whether the two genotypes differed in the development of a local immune response. Immunofluorescence staining was used to detect ACC and ICC of IgA, IgG1, IgG2 and IgM classes. No ACC were found in the abomasum of any of the sheep before infection. ACC were first detected in the abomasal mucosa of both the resistant and susceptible sheep seven days after infection, reached a peak level on day 21 and then declined. At all observation times, the majority of ACC in both genotypes were of the IgA isotype, followed by IgG1 and IgM. The IgG2-ACC response was negligible compared with the IgA and IgG1 response. The comparison of genotypes showed that the resistant sheep had significantly more IgA-ACC on days 14, 21, 28 and 35, and significantly more IgG1-ACC than random-bred sheep on days 14, 21 and 28. The numbers of IgG2- and IgM-ACC did not differ between the genotypes. The abomasal mucosa of the resistant sheep was also found to have significantly more ICC than the mucosa of random-bred sheep; IgA-ICC predominated at all the observation times followed by IgG1 and IgM. These results suggest that IgA and IgG1 antibodies, produced locally in response to infection, may play a role in mediating genetic resistance to haemonchosis in sheep.

Effect of Ostertagia ostertagi secretions and various putative secretagogues and inhibitors on aminopyrine accumulation in dispersed bovine abomasal gland cells.

Aminopyrine accumulation in suspensions of isolated gastric glands was used to determine the effect of Ostertagia ostertagi secretions and putative secretagogues and inhibitors on abomasal parietal cells. Parasite secretions did not affect acid production nor did histamine. Dibutyryl cyclic adenosine monophosphate (cAMP) and pentagastrin significantly increased aminopyrine accumulation by gastric glands and cimetidine, omeprazole and thiocyanate significantly decreased aminopyrine accumulation confirming their roles as stimulators and inhibitors of gastric acid production, respectively.

Light and electron microscopic investigation of the lectin-binding pattern in the oxyntic gland region of bovine abomasum.

For the first time the expression of glycoconjugate residues in the oxyntic gland region of bovine abomasum has been investigated by means of lectin histochemistry. For light microscopic investigations, a battery of ten lectins, Con A, PSA, UEA I, WGA, LEA, SNA, RCA120, MPA, DBA and SBA was used. For electron microscopic examinations, WGA and RCA120 were utilized. The staining pattern of the lectins in all exocrine cell types of the oxyntic gland region is described. Compared to the results of monogastric species our study reveals some similarities, but just as many differences in the composition of glycoconjugate residues in bovine exocrine cell types. Typical for surface mucous cells is the amount of L-fucose, N-acetyl glucosamine residues and Galbeta1, 4GlcNAc sequences in the secretory granules. SNA could serve as a marker for surface mucous cells, because this lectin exclusively stains the plasma membrane and the secretory granules of surface mucous cells and the extracellular mucus. L-fucose and N-acetyl glucosamine are typical for the secretory granules of mucous neck cells. In addition, the secretory granules show the highest amount of N-acetyl galactosamine residues of all exocrine cells, so that DBA and SBA are recommended as marker lectins for mucous neck cells. Most lectins strongly stain the intracellular membrane system of oxyntic cells. The cocktail of glycoconjugates in the vicinity of the HCI production site provide protection against chemical injury. In chief cells only the apical plasma membrane is more or less labeled with all lectins apart from SNA. Specific marker lectins for oxyntic cells or chief cells of the bovine have not been characterized.

Histomorphometric analysis of the abomasum of the sheep during development.

Histomorphometric analyses were carried out on 64 embryos and fetuses and on 20 sheep (early postnatal to adult age). Histodifferentiation of the abomasum took place at 33 days of fetal life, with the appearance of abomasal villi at 53 days. By 64 fetal days, the epithelium had changed from pseudostratified to simple mucous cylindrical. Acidic glycoproteins appeared at 46 fetal days. Neutral glycoproteins did not appear until later stages of development, near birth. We believe that the configuration of a simple epithelium with acidic secretion is enhanced at birth by the secretion of neutral glycoproteins which act as a buffer against acidic substances, and particularly against the abomasal acidity during lactation. Growth curves and formulae were set out for each tissue layer.

An immunohistochemical study of endocrine cells in the abomasum of vagotomized calf.

The effect of thoraco-vagotomy on the distribution and frequency of chromogranin-, serotonin-, somatostatin- and gastrin-immunoreactive cells in the abomasum of the calf were investigated by immunohistochemistry. Calves were vagotomized at 1 week old and sampled 2 and 4 weeks later. The endocrine cells generally decreased in number in vagotomized calves as compared to non-operated control calves. However, the detailed responses of endocrine cells to vagotomy varied depending on the endocrine cell type, region of gastric mucosa, and period after vagotomy. The present result suggests that the vagus nerve has an influence on the intrinsic regulatory system by endocrine cell control in the ruminant abomasum.

Histologic and immunocytochemical study of endocrine cells in the gastrointestinal tract of the cow and calf.

The regional distribution and relative frequency of argyrophil cells, and of cells immunoreactive for 5-hydroxytryptamine (5-HT), substance P (SP), somatostatin, glicentin, glucagon, bovine pancreatic polypeptide (BPP), gastrin, leucine-enkephalin, gastric inhibitory polypeptide (GIP), cholecystokinin, secretin, motilin, and neurotensin were studied in 9 segments from the gastrointestinal tract of cows (greater than 1 year old) and calves (less than 3 months old). Argyrophil cells, 5-HT-immunoreactive cells, and somatostatin-immunoreactive cells were distributed throughout the gastrointestinal tract, whereas the other immunoreactive cells were more restricted in distribution. Most endocrine cells were more numerous in the calf than in the cow. This feature was most conspicuous in the abomasum. In the abomasum, argyrophil cells in the cow and calf and 5-HT-immunoreactive cells in the calf were found predominantly in the fundic region, whereas somatostatin-immunoreactive cells and gastrin-immunoreactive cells in the cow and calf and 5-HT-immunoreactive cells in the cow were most numerous in the pyloric region. Substance P-, glucagon-, BPP-, and leucine-enkephalin-immunoreactive cells were rarely detected. In the small intestine, argyrophil cells, 5-HT-, SP-, somatostatin-, gastrin-, GIP-, cholecystokinin-, secretin-, and motilin-immunoreactive cells were most numerous in the duodenum. Neurotensin-, glicentin-, glucagon-, and BPP-immunoreactive cells were detected with the highest frequency in the ileum. In the large intestine, argyrophil cells and 5-HT-, glicentin-, BPP-, somatostatin-, glucagon-, and SP-immunoreactive cells occurred with the highest frequency in the rectum.

Adverse immune reactions and the pathogenesis of Ostertagia ostertagi infections in calves.

The possible development of type-1 hypersensitivity reactions in the abomasal mucosa caused by soluble L3 products of Ostertagia ostertagi was studied in 4-month-old calves sensitized by repeated exposure to L3 over a 50-day period followed by anthelmintic treatment. Four groups each of 4 calves were used. Group 1 served as nonsensitized controls and group 2 as sensitized controls, group 3 was challenge exposed at 2-week intervals beginning at week 10 with a soluble L3 product (OAG), and group 4 was challenge exposed at 2-week intervals with an oral dose of L3, followed by anthelmintic treatment 3 days later. All calves infected with L3 became sensitized, as indicated by a positive reaction to an intradermal skin test. However, a passive cutaneous anaphylaxis was only partly effective in indicating the presence of homocytotropic antibody in the infected calves. Sensitized calves had significantly (P less than 0.05) higher eosinophil counts and plasma pepsinogen values for the entire 14 weeks than uninfected controls. Globule leukocyte and mast cell counts from the abomasal mucosa were also significantly (P less than 0.05) higher. Studies for possible immunomodulation revealed that lymphocyte counts decreased between every 2-week challenge-exposure period for groups-3 and -4 calves. A transient depression of blood lymphocyte (BL) responses to phytohemagglutinin (PHA), a T-cell mitogen, was observed over the first 8 weeks in the infected calves. Increases in BL responses to OAG were also observed. Differences were not observed in BL responses to pokeweed mitogen, a T- and B-cell mitogen. Blood lymphocyte responses to PHA in group-3 calves were low following the initial challenge exposure with OAG.(ABSTRACT TRUNCATED AT 250 WORDS)

Do the cardiac glands exist? 7. The cow.

The glands distributed in the narrow region of the abomasum contiguous to the omasum of the cow have been described as cardiac glands. We doubted this assertion and therefore performed histological and histochemical investigations of the glands to clarify their characteristics. 1. All glandular cells except the parietal cells in a few glands contiguous to the omasum react strongly to PAS, AB(pH 2.5), and PAS-AB(pH 2.5) staining, and moderately to AB(pH 0.5) staining. 2. Glandular cells at the base of these glands contain fine pepsinogen granules and a few parietal cells are distributed in these glands, indicating that they are undifferentiated gastric glands and that the so-called cardiac glands do not exist in the cow stomach. 3. Glandular cells in undifferentiated gastric glands are filled with PAS, AB(pH 2.5 and 0.5) and PAS-AB(pH 2.5) positive substances. Which gradually decrease and finally disappear with differentiation, remaining only in the neck (mucous neck cells) and the cells in the upper part of the glandular body (immature chief cells), in mature gastric glands. 4. Mature chief cells in differentiated gastric glands are distributed in the middle and lower bodies and base of the glands and contain a number of PAS and PAS-AB(pH 2.5) positive granules and a large number of coarse pepsinogen granules, while pepsinogen granules in the mucous neck cells and immature chief cells are finer. 5. In the cow the region in which undifferentiated gastric glands are located is very narrow. 6. Parietal cells in the cow stomach are numerous.(ABSTRACT TRUNCATED AT 250 WORDS)

Pathway of programmed cell death and oxidative stress induced by ß-hydroxybutyrate in dairy cow abomasum smooth muscle cells and in mouse gastric smooth muscle.

The administration of exogenous ß-hydroxybutyrate (ß-HB), as well as fasting and caloric restriction, is a condition associated with ß-HB abundance and decreased appetite in animals. Increased ß-HB and decreased appetite exist simultaneously in some diseases, such as bovine left displaced abomasums (LDA) and human chronic gastritis. However, the effects of ß-HB on stomach injuries have not been explored. To elucidate the possible effects of exogenous ß-HB on the stomach, mice were injected intraperitoneally with ß-HB, and bovine abomasum smooth muscle cells (BSMCs) were treated with different concentrations of ß-HB. We found that ß-HB induced BSMCs endoplasmic reticulum- and mitochondria-mediated apoptotic cell death. ß-HB promoted Bax expression and caspase-12, -9, and -3 activation while blocking Bcl-2 expression. ß-HB also promoted AIF, EndoG release and p53 expression. ß-HB acted on key molecules in the apoptotic cell death pathway and increased p38 and c-June NH2-terminal kinase phosphorylation while inhibiting ERK phosphorylation and PCNA expression. ß-HB upregulated P27 and P21 mRNA levels while downregulating cyclin and CDK mRNA levels, arresting the cell cycle. These results suggest that BSMCs treated with ß-HB can induce oxidative stress, which can be prevented by intracellular calcium chelators BAPTA/AM but not antioxidant NAC. Additionally, these results suggest that ß-HB causes ROS generation through a Ca2+-dependent mechanism and that intracellular Ca2+ levels play a critical role in ß-HB -induced apoptotic cell death. The impact of ß-HB on programmed cell death and oxidative stress in vivo was confirmed in murine experiments. For the first time, we show oxidative stress effects of ß-HB on smooth muscle. We propose that ß-HB is a possible cause of some stomach diseases, including bovine LDA.

Differential immune response between fundic and pyloric abomasal regions upon experimental ovine infection with Haemonchus contortus.

The effect of experimental haemonchosis on the number of tissue eosinophils, plasma cells and lymphocyte subpopulations was evaluated in the fundic abomasal region, the pyloric abomasal region and the abomasal lymph node of Blackbelly lambs, which are resistant to infection, and Columbia lambs, which are susceptible to infection. An increase in the number of tissue eosinophils and CD4+ and WC1(+)γδ T-cells was observed in the pyloric abomasal region of Blackbelly lambs and correlated with lower worm burden and greater resistance to infection. Increases in IgA+ plasma cells from the pyloric abomasal region were observed in both infected groups, but there was no difference between the groups. Therefore, increases in IgA+ plasma cells did not explain the resistance observed. Infection caused a significant increase in tissue eosinophils in the abomasal lymph node of Blackbelly lambs and a decrease in the number of CD4+ T-cells in lambs of both breeds. CD8+ T-cells and IgG+ and IgM+ plasma cells were not associated with either infection or resistance. In this work, clear differences were observed in the numbers of CD4+ and WC1(+)γδ T-cells, tissue eosinophils and IgA+ plasma cells between the abomasal regions studied. These differences indicate that the immunological response is not homogenous in all abomasal mucosa and that evaluating the response from a single abomasal region may not be representative of the cellular response across the abomasum.

Peritoneal fluid analysis in dairy cows with left displaced abomasum and abomasal volvulus.

Peritoneal fluid (PF) was evaluated in 40 cows with left displaced abomasum (LDA) and 15 cows with abomasal volvulus (AV). PF was obtained by abdominocentesis at the right ventral abdomen at admission. Simultaneously, a blood sample was taken from the jugular vein. Biochemical and cytological variables in blood and PF specific for ischaemia, inflammation and cell damage were compared. Total protein, albumin, glucose and cholesterol were normal in PF of cows with LDA and AV. Although L-lactate increased in both groups, cows with AV had significantly higher values (LDA: 1.47/0.69/2.68 mmol/l; AV: 6.45/4.55/12.89 mmol/l (median/1. quartile/3. quartile)). D-dimer (LDA: 0.50/0.22/0.88 mg/l; AV: 1.11/0.40/1.85 mg/l) and LDH (LDA: 663/437/943 U/l; AV: 1099/750/1439 U/l) were only increased in PF of cows with AV. The number of leucocytes was normal; however, significantly more peritoneal neutrophils appeared necrotic or apoptotic after AV. PF of cows with abomasal displacement showed distinctive features of ischaemia and inflammation. Characteristics of haemostatic dysfunction and cell damage were mainly evident in PF of cows with AV. The results suggest that anti-inflammatory therapy is indicated in each cow with abomasal displacement. Additionally, medical treatment should be directed to prevent complications of ischaemia and reperfusion in cows with AV.