The development of intestinal lesions after inoculation with Brachyspira hyodysenteriae was followed by repeated endoscopy and biopsy sampling through a caecal cannula. Seven eight-week-old pigs were cannulated and inoculated, two were cannulated but not inoculated, and two pigs were inoculated but not cannulated. Endoscopy, biopsy, and blood sampling to determine SAA (serum amyloid A), haptoglobin, cortisol, and WBC counts were performed at scheduled time-points. At the third day of disease, endoscopy showed a hyperaemic, perturbed mucosa and excessive amount of mucus. Histologically, crypt hyperplasia, depletion of goblet cell mucus, and erosions were noted. Simultaneously, elevated acute phase proteins and circulating monocytes, and decreased number of intraepithelial CD3(+) cells were observed. After five days the pigs recovered. Intestinal lesions were demarcated and interspersed among apparently normal mucosa and blood parameters returned to initial values. Endoscopy through an intestinal cannula made it possible to follow the development of intestinal alterations in vivo and describe the sequential events during the course of swine dysentery. The number of animals used in a study could thus be minimised and the precision of the experiment increased.
The aim of this study was to examine blood concentrations of amino acids, glucose and lactate in association with experimental swine dysentery. Ten pigs (approximately 23kg) were orally inoculated with Brachyspira hyodysenteriae. Eight animals developed muco-haemorrhagic diarrhoea with impaired general appearance, changes in white blood cell counts and increased levels of the acute phase protein Serum Amyolid A. Blood samples were taken before inoculation, during the incubation period, during clinical signs of dysentery and during recovery. Neither plasma glucose nor lactate concentrations changed during the course of swine dysentery, but the serum concentrations of gluconeogenic non-essential amino acids decreased during dysentery. This was mainly due to decreases in alanine, glutamine, serine and tyrosine. Lysine increased during dysentery and at the beginning of the recovery period, and leucine increased during recovery. Glutamine, alanine and tyrosine levels show negative correlations with the numbers of neutrophils and monocytes. In conclusion, swine dysentery altered the blood concentrations of amino acids, but not of glucose or lactate.
The aim of this study was to examine changes in the systemic immune response during the incubation period and following the onset of clinical swine dysentery, including the recovery period. Ten healthy conventional pigs were inoculated with Brachyspira hyodysenteriae. Blood was sampled at pre-inoculation, at days 4 and 14 post-inoculation, during the first 4 days with clinical signs of dysentery and at days 1, 3, 7, 11 and 15 of the recovery period. Eight pigs developed haemorrhagic diarrhoea. Flow-cytometric analyses of lymphocyte subpopulations showed that all animals, including the two that remained healthy, had an increase in CD8alpha+ CD4- cells and gammadelta T cells at days 4 and 14 post-inoculation. In addition, an increase in CD4+ CD8alpha+ cells and CD8alpha+ CD8beta+ cells was observed at days 4 and 14 post-inoculation in animals that developed dysentery. During clinical signs of dysentery, the acute-phase protein serum amyloid A was increased. There was a two- to threefold increase in both neutrophils and monocytes during signs of dysentery and at the beginning of the recovery period. The numbers of CD8alpha+ CD8beta- CD4-, CD45RA- lymphocytes also increased during the dysentery period. Circulating CD21+ cells and CD21+ CD45RA- cells decreased at the end of the incubation period, during signs of dysentery and at the beginning of the recovery period. The dysentery-affected animals developed antibodies to B. hyodysenteriae-specific antigens (approximately 16 kDa and approximately 30 kDa) from the first day of recovery, and gammadelta T cells showed an increase during the recovery period. In comparison with pre-inoculation, increased numbers of monocytes, neutrophils, CD8alpha+ CD8beta- CD4- lymphocytes and CD45RA- lymphocytes were observed during clinical dysentery. Increased numbers of neutrophils, gammadelta T cells and specific antibodies were seen during the recovery period.
REASONS FOR PERFORMING STUDY The degradation of glycogen and its two forms, proglycogen (PG) and macroglycogen (MG) has been studied in horses performing different types of exercise, but no information is available about the resynthesis of PG and MG after exercise. OBJECTIVES To determine the resynthesis of PG and MG in skeletal muscle after intermittent uphill exercise. METHODS At a training camp 9 well-trained Standardbred trotters performed a training session comprising a warm-up period, 7 repeated 500 m bouts of exercise on an uphill slope and a recovery period. Muscle biopsies (m. gluteus medius) for analysis of PG, MG, glucose and glucose-6-phosphate were taken at rest, at the end of exercise and 1, 4, 8, 24, 48 and 72 h post exercise. Blood samples for analysis of glucose, lactate and insulin were collected before exercise, immediately after the last bout of exercise and then as for the muscle biopsies. RESULTS The MG and PG concentration pre-exercise was 311 - 47 and 305 +/- 55 mmol/kg dwt respectively. The exercise caused a decrease in PG (A 63 +/- 26 mmol/kg dwt) and MG (delta 136 +/- 68 mmol/kg dwt). Immediately after the last sprint plasma glucose and lactate increased compared to values pre-exercise. During the first hour post exercise there was a further decrease in MG in 7 out of 9 horses. The rate of glycogen resynthesis during 1-24 h was higher for MG than for PG. The rate of muscle glycogen resynthesis thereafter was slower and did not differ between MG and PG up to 72 h. CONCLUSION After repeated bouts of exercise on a slope, resynthesis of glycogen is a slow process and the resynthesis of proglycogen differs from that of macroglycogen. The fraction most depleted during exercise (MG) had no resynthesis during the first hour of recovery but then had the highest rate of resynthesis during the remainder of the first 24 h period. POTENTIAL RELEVANCE If the time between exercise sessions during training is too short the recovery period will be inadequate for complete restoration of muscle glycogen.
OBJECTIVE:To investigate influence of the Rendement Napole (RN-) mutation on proglycogen (PG) and macroglycogen (MG) content in skeletal muscles before and after exercise and evaluate glycogen concentrations within various muscle fiber types.ANIMALS:5 pigs with the RN- mutation and 3 noncarrier pigs.PROCEDURE:Pigs performed 2 exercise tests on a treadmill. In the first, pigs (mean body weight, 27 kg) ran a distance of approximately 800 m. In the second, pigs (mean body weight, 63 kg) ran until fatigued. Biopsy specimens (biceps femoris muscle) for determination of PG and MG contents were obtained before and after exercise, 24 hours after the first test, and 3 hours after the second test. Histochemical analysis was performed on specimens obtained before and after the second test.RESULTS:Before exercise, PG stores did not differ markedly between groups, but MG stores were twice as high in pigs with the RN- mutation, compared with noncarrier pigs. The MG content decreased to a similar extent in both groups after exercise. Resynthesis of MG was greater in pigs with the RN- mutation than in noncarrier pigs by 3 hours after exercise. A low glycogen content after exercise was observed in many type I and type IIA fibers and in some type lIB fibers.CONCLUSIONS AND CLINICAL RELEVANCE:The RN- mutation was associated with high MG stores in skeletal muscle that did not influence exercise performance. The RN- mutation did not impair glycogenolysis during exercise but may induce faster resynthesis of MG after exercise.
The aim of this study was to examine the levels of circulating leukocytes and lymphocyte subpopulations before and immediately after experimentally induced swine dysentery. Twenty-one healthy crossbred pigs (approximately 22 kg) were orally inoculated with Brachyspira hyodysenteriae. Blood was sampled before inoculation and when clinical signs of swine dysentery occurred. Pigs that remained healthy were sampled when killed. Total and differential white blood cell counts were performed, and lymphocyte subpopulations were analysed using flow cytometry. Following a mean incubation period of 13 days, 12 pigs developed swine dysentery, whereas nine remained healthy throughout the study. Before inoculation, pigs that subsequently developed swine dysentery displayed higher levels of circulating gamma delta T cells (mean +/- se; 30.7 +/- 3.5 %) compared with pigs that remained healthy (14.9 +/- 1.4 %). Sick animals also displayed lower levels of CD8 cells (24.6 +/- 1.5 %), cytotoxic/suppressor T cells (10.9 +/- 1.3 %) and CD4 CD8 T cells (8.1 +/- 1.0 %) than the pigs that remained healthy (34.9 +/- 3.1 %; 17.6 +/- 2.0 %; 13.6 +/- 2.3 %). No difference was observed in leukocyte counts before inoculation. At onset of swine dysentery, there was an increase in monocytes (from 1.5 +/- 0.2 x 10 to 3.8 +/- 0.5 x 10 l) and CD4 CD8 T cells (from 5.8 +/- 0.9 to 8.9 +/- 0.7 %). In conclusion, gamma delta T cells and CD8 cells may be associated with susceptibility to experimentally induced swine dysentery, whereas monocytes and CD4 CD8 T cells appear to be the major responding leukocytes during the disease.
The purpose was to investigate the degradation of proglycogen and macroglycogen in skeletal muscle during intense exercise. Ten Standardbred trotters performed a maximal treadmill exercise test comprising a warm-up period, an exercise period, starting at 7 m/s with increments of 1 m/s every 60 s until the onset of fatigue (mean +/- s.d. 246 +/- 32 s) and a walking recovery period. Muscle biopsies were taken at rest, immediately after exercise and 15 min postexercise. The exercise caused a marked anaerobic metabolism as shown by the decrease in both muscle ATP and creatine phosphate and increase in muscle lactate. Free muscle glucose increased immediately postexercise and a further increase was noted 15 min later. There was a significant decrease (P<0.05) in proglycogen (57.1 +/- 22.2 mmol/kg dw) and macroglycogen (63.0 +/- 65.5 mmol/kg dw) during exercise. The proglycogen concentration tended to increase 15 min after exercise (19.9 +/- 27.3 mmol/kg dw; P = 0.06). The results from this study demonstrate that both proglycogen and macroglycogen contribute equally to glycogenolysis during intense exercise and suggest that glycogen resynthesis starts in the proglycogen pool.
Three methods for quantifying aluminum in water samples are compared. An electrothermal atomic absorption method is assumed to be free of interferences and has an applicable range of 10 to above 1000 μg Al l-1. The colorimetric ferron method has multiple interferences and is useful in the 50–1500 μg Al l-1 range. The fluorimetric method based on lumogallion has few important interferences and is useful to below 1 μg Al l-1.