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1.
The concentration of potassium in plasma and in red blood cells was determined in 948 horses. The coefficient of correlation between the two parameters was low. In 436 of these horses, which were clinically healthy, the red blood cell potassium (RBCK+) levels did not fit within a normal distribution curve, but a bimodal distribution was observed with a section point at 90 mmol/litre. In 90 per cent of these normal horses, mean RBCK+ content was 97.5 mmol/litre. In the remaining 10 per cent, mean RBCK+ concentration was 93.8 mmol/litre. A subdivision into a ‘low potassium group’ and a ‘high potassium group’ was made. In 10 out of 15 horses in the ‘low potassium group’, bimonthly sampling over a period of one year showed that RBCK+ content remained low. In the remaining five horses an increase was observed.  相似文献   

2.
Six broodmares that were genetically tested to be heterozygous (H/N) and six broodmares that were tested to be homozygous negative (N/N) for Equine Hyperkalemic Periodic Paralysis (HYPP), that were descendents of the same stallion, were used in a replicated 3×3 Latin square experiment to determine the genetic-diet relationships in the HYPP syndrome.1 The mares were fed rations consisting of 65% pelleted concentrate and 35% Coastal Bermuda grass hay that provided 1.1 (diet A), 1.9 (diet B) and 2.9% (diet C) potassium. The experimental periods were 14 days long, resulting in 28 meals per period. At meals 1 and 27, blood samples were taken every 30 minutes for 12 hours and every 10 minutes from 2 to 5 hours post-feeding. Total urine and fecal collections were made on the last 4 days of each period.Water, feed and fecal samples were analyzed for sodium and potassium content. Blood was analyzed for packed cell volume (PCV) and plasma potassium (K+) and sodium (Na+) concentrations.Apparent absorption of potassium was 99.8% across all diets, and potassium was excreted principally in the urine. More potassium was retained when the horses were fed diet B than diets A or C. Apparent absorption of sodium was 99.6% with no difference by diet. Neither potassium nor sodium balances were affected by HYPP status.There was no post-prandial pattern of plasma K+ concentration seen when the horses were fed the low potassium diet. When fed the higher potassium diets, they had greater plasma K+ values and exhibited a post-prandial peak at 2 to 5 hours after feeding. This peak occurred in all of the horses, meaning that plasma K+ cannot be used as a diagnostic aid for the presence of the HYPP mutation. By meal 27, some adaptation had occurred resulting in lower plasma K+ values when the horses were fed the higher potassium diets. The horses had increased plasma K+ concentrations throughout the post-prandial period while fed diet B compared to diet A, agreeing with the positive potassium balance seen in this experiment. The HYPP H/N horses had lower plasma Na+ concentrations in the early post-prandial hours and continuously greater PCV values than the HYPP N/N horses.  相似文献   

3.
This study was conducted to investigate the relationships between the concentrations of potassium, sodium, calcium and magnesium of plasma and muscle in horses, as interactions between these ions can be important in the development of muscle cell injury. Blood samples and gluteal muscle biopsies were taken from 20 healthy Standardbreds to determine the potassium concentration in plasma (cK+(P)), red blood cells (cK+(RBC)), and muscle (cK+(M)), and the calcium and magnesium concentrations in plasma and muscle. No correlations were found between cK+(P), cK+(RBC), and cK+(M). Significant positive correlations were found between cK+(M) and muscle magnesium (p<0.01); and cK+(P) and plasma calcium (p<0.005). Significant negative correlations were found between cK+(M) and the percentage of muscle water (p<0.005); and the muscle magnesium and calcium concentrations (p<0.02).  相似文献   

4.
This study demonstrated that the feeding of treatment diets with calculated dietary cation-anion balances (DCAB) of +370.43 (H) and -25.69 (L) did not have significant effects on blood pH, pCO2, and HCO3-. Serum Ca2+, P, Na+, and Cl- as well as plasma PTH did not differ (P > .05) between the two treatment groups. Serum K+ was higher (P< .05) in horses fed diet H rather than diet L. The DCAB of the diet significantly affected urinary Ca2+, P, Na+, K+, and Cl- excretion in the young growing horse. Urine Ca2+ and Cl- levels were higher (P < .01) in horses fed diet H versus diet L. Furthermore, levels of P, Na+, and K+ in the urine were higher (P < .01) in horses on diet H as opposed to diet L. Results of this study indicate that horses were able to maintain acid-base status regardless of diet. However, these data imply that growing horses consuming diets low in DCAB may be predisposed to abnormal bone mineralization due to the increase in calcium excretion which could lead to a weakening of the skeletal system.  相似文献   

5.
Equine recurrent uveitis (ERU) is an immune‐mediated disease causing repeated or persistent inflammatory episodes which can lead to blindness. Currently, there is no cure for horses with this disease. Mesenchymal stem cells (MSCs) are effective at reducing immune cell activation in vitro in many species, making them a potential therapeutic option for ERU. The objectives of this study were to define the lymphocyte phenotype of horses with ERU and to determine how MSCs alter T‐cell phenotype in vitro. Whole blood was taken from 7 horses with ERU and 10 healthy horses and peripheral blood mononuclear cells were isolated. The markers CD21, CD3, CD4, and CD8 were used to identify lymphocyte subsets while CD25, CD62L, Foxp3, IFNγ, and IL10 were used to identify T‐cell phenotype. Adipose‐derived MSCs were expanded, irradiated (to control proliferation), and incubated with CD4+ T‐cells from healthy horses, after which lymphocytes were collected and analyzed via flow cytometry. The percentages of T‐cells and B‐cells in horses with ERU were similar to normal horses. However, CD4+ T‐cells from horses with ERU expressed higher amounts of IFNγ indicating a pro‐inflammatory Th1 phenotype. When co‐incubated with MSCs, activated CD4+ T‐cells reduced expression of CD25, CD62L, Foxp3, and IFNγ. MSCs had a lesser ability to decrease activation when cell‐cell contact or prostaglandin signaling was blocked. MSCs continue to show promise as a treatment for ERU as they decreased the CD4+ T‐cell activation phenotype through a combination of cell‐cell contact and prostaglandin signaling.  相似文献   

6.
Reasons for performing study: The incidence and implications of positive blood cultures in mature horses with diarrhoea is unknown. The diagnosis of bacteraemia may alter treatment and prognosis. Hypothesis: The proportion of horses with diarrhoea that are blood culture positive is higher than previously assumed and a positive blood culture has a negative impact on survival. Methods: Blood cultures were taken at admission and 24 h after admission from 31 mature horses with diarrhoea. Results: Nine (29%) horses were blood culture positive within 24 h of admission. Organisms isolated included Corynebacterium spp. (n = 6), Streptococcus spp. (n = 2), Pantoea agglomerans (n = 1), Gram‐negative rod (n = 1), Bacillus spp. (n = 1) and yeast (n = 1). Horses with positive blood cultures were significantly less likely to survive. Prior treatment with antimicrobial drugs had no significant effect on blood culture status. Horses with positive blood cultures had a significantly higher heart rate, packed cell volume (PCV) and plasma potassium concentration at admission, and a higher PCV and lower total plasma protein concentration 24 h after admission. Conclusions: Positive blood cultures occur more frequently than previously reported, and may have a negative impact on survival in horses with diarrhoea. Potential relevance: Results of blood cultures may be useful in formulating a prognosis for horses with diarrhoea. Further research is required to determine the effect of antimicrobial treatment on outcome.  相似文献   

7.
Summary

In the present study E. coli strains isolated from the faeces of ten horses with diarrhoea and 14 horses without diarrhoea were characterized. All horses were culture negative for Salmonella species. Nine colonies of E. coli from each faecal sample were picked at random and a DNA fingerprint was made by means of a polymerase chain reaction (PCR) using Enterobacterial Repetitive Intergenic Consensus (ERIC) primers. The number of E. coli genotypes did not differ significantly between horses with and without diarrhoea. In addition, all E. coli strains with different DNA fingerprints were tested by PCR for genes encoding the virulence factors K88, F41, F17, CS31a, Stal, LT1, VT2, CNF, BFP, and intimin. Genes coding for K88, F41, BFP, STal, VT2, and CS31A were not detected. Genes for CNF were found in strains from one horse with diarrhoea and one horse with normal faeces. Genes for LT1 (n=1) and intimin (n=1) were found only in strains from horses with normal faeces. Genes for F17 fimbriae were found in strains from three horses with diarrhoea (30%) and in none of the strains from healthy horses. In two of these horses, E. coli strains with different DNA polymorphism patterns were F17 positive; however, none of these strains possessed LT1, Sta1, or CNF genes. Haemolytic E. coli strains were only isolated from two horses with diarrhoea and from none of the healthy horses. Nineteen percent of all E. coli strains did not ferment lactose. Eight per cent of these lactose‐negative strains were from horses with diarrhoea, whereas 32% were from horses without diarrhoea. In conclusion, virulence factors were present in E. coli isolates from horses with and without diarrhoea, except for F17, which was only found in E. coli isolated from horses with diarrhoea. F17‐positive E. coli might have importance as cause of diarrhoea in horses, but further studies are needed.  相似文献   

8.
Reasons for performing the study: Intestinal hyperammonaemia (HA) has been infrequently reported in individual horses; however, there have been no studies describing clinical and laboratory data as well as short‐ and long‐term outcome in a larger number of cases. Objectives: To describe clinical and laboratory data and short‐ and long‐term outcome in a large group of horses with intestinal HA. Methods: Multi‐centred, retrospective study; case records of horses with HA were reviewed and any horse with a clinical or post mortem diagnosis of intestinal HA was included. Hyperammonaemia was defined as a blood ammonium (NH4+) concentration ≥60 µmol/l and horses with a diagnosis of primary hepatic disease were excluded. Relevant data were recorded and, if appropriate, data from survivors were compared to nonsurvivors to identify potential prognostic indicators. Results: Thirty‐six cases, 26 mature horses and 10 foals with intestinal HA were identified. Case histories included diarrhoea, colic and neurological signs and the most common clinical diagnosis was colitis and/or enteritis. The most common clinical and laboratory abnormalities included tachycardia, increased packed cell volume, hyperlactataemia and hyperglycaemia. Fourteen horses (39%) survived to discharge; NH4+ concentration on admission was the only parameter significantly associated with survival. All surviving horses and foals for which follow‐up information was available recovered completely and returned to their intended use without further complications. Conclusions and potential relevance: Intestinal HA occurs in mature horses and foals and can be associated with severe clinical and laboratory abnormalities; further studies are required to investigate predisposing factors and delineate possible differences in aetiologies.  相似文献   

9.
SUMMARY Vitamin B12 and folate concentrations were determined by radioimmunoassay in groups of horses in Queensland. Highest serum vitamin B12 levels were found in supplemented performance horses. These, together with pastured horses that included pregnant and lactating mares, had significantly greater serum folate activity than permanently stabled animals. The range of red cell folate concentrations was much narrower in horses in training than from any other group. Red cell folate may be a better indicator of a horse's folate status than the serum folate value. Vitamin B12 and folate concentrations were highest in spring and summer. Small intestinal dysfunction in 2 horses was not associated with vitamin B12 or folate malabsorption. Serum folate levels returned to normal 24 h after intramuscular injections of 75 to 150 mg folic acid, whereas serum vitamin B12 values remained elevated for at least one week following injections of 8 to 10 mg to non-supplemented horses.  相似文献   

10.
Cytokines produced by T helper (Th) cells are important in orchestrating the immune response during health and disease. Recent reports indicated that cytokine mRNA expression in foals is often quantitatively lower than that of adult horses suggesting that foal T cells are not fully mature. Here, peripheral blood mononuclear cells from foals and adult horses were stimulated with phorbol 12-myristate 13-acetate and analyzed for intracellular interferon-gamma (IFN-γ), interleukin-4 (IL-4) and IL-10 production, representing the Th1, Th2 and regulatory TR1 cell phenotypes respectively, by flow cytometry. In agreement with previous reports, all three cytokines were quantitatively reduced in foals compared to adults. However, the balance between Th1 and Th2 cytokines (IFN-γ/IL-4 ratio) showed a clear Th1-biased response in foals by 6 and 12 weeks of life, while similar IFN-γ/IL-10 ratios were found in foals and adult horses. By day 5 after birth, intracellular IFN-γ production by foal CD4+ and CD8+ T cells resembled that in adults. Overall, IL-4 production was low in foals. IL-4+ cells peaked at day 5 of age when IL-4 was mainly produced by IgE+ cells. Relative percentages of IL-4+ Th2 cells were significantly lower in foals at all time points. The data suggested that equine neonates and young foals have an impaired Th2 response, that the immune response of foals is Th1 biased, that IFN-γ production by Th and cytotoxic T cells is qualitatively similar to adult horses, and regulatory IL-10 production by T cells is developmentally mature in foals during the first three months of life.  相似文献   

11.
High-intensity exercise and competition are associated with depressed immune function. Young horses, which participate in high-intensity exercise and competitions, are at increased risk for the development of infectious disease due to depression of immune function. The effects of branched-chain amino acid (BCAA) supplementation on the immune status of young racing horses were evaluated, determining whether BCAA might help to avoid or reduce immune suppression during exercise and competitions. Twenty horses (10 male and 10 female) were treated with BCAA supplementation; another twenty untreated horses (10 male and 10 female) constituted control group. Peripheral blood was collected from each animal and evaluated for lymphocyte subsets, phagocytosis analysis of monocytes and granulocytes, lymphocyte proliferative response, and expression of cytokine-encoding messenger ribonucleic acids (mRNAs). The numbers of CD4+, CD8+, and major histocompatibility complex (MHC) class II+ cells in females of the treated group were significantly higher than those in females of the control group. The lymphocyte proliferative response in female of the treated group also was significantly higher than that in females of the control group. In addition, expression of mRNAs encoding interleukin-1β (IL-1β) and interferon-γ (IFN-γ) in females of the treated group was significantly higher than that in females of the control group. There were no significant differences between males of the treated and control groups. The results of this study indicated the positive effects of BCAA supplementation in counteracting immunosuppression in young female racing horses during and following high-intensity exercise.  相似文献   

12.
To study the canine immune system we generated a mouse model engrafted with canine lymphocytes using NOD SCID IL2R common gamma chain ?/? (NSG) mice as recipients (Ca-PBL-SCID). Engraftment of canine peripheral blood lymphocytes (PBLs) was determined post-injection with 107 peripheral blood mononuclear cells (PBMCs) into irradiated NSG mice using flow cytometry and fluorescently labeled antibodies specific to canine helper T cells (CD45+ CD4+), cytotoxic lymphocytes (CD45+ CD8+), regulatory T cells (CD45+ CD4+ Foxp3+), and B cells (CD45+ Ig+ CD21lo). Canine CD45+ lymphocytes were detectable as early as day 1 in the peritoneal cavity, and beginning at 9 days in the blood, bone marrow, and spleen. CD4+ T cells, of which Foxp-3+ CD25hi cells constituted a minor percentage, were the predominant lymphocyte population at 9 days post engraftment contrasting with increasing proportions of CD8+ CTL's and Ig+ B cells beginning at 16 days. Canine immunoglobulin was initially detected in the serum of Ca-PBL-SCID mice at 9 days post-engraftment and peaked in concentration at day 36. From day 28 to 52 post-engraftment 30% of the Ca-PBL-SCID mice became markedly anemic and thrombocytopenic, yet gross and histopathologic examination of bone marrow, kidneys, spleen, liver, and intestine revealed no obvious lesions. Blood smear evaluation revealed agglutination of mature red blood cells, reticulocytes and a regenerative anemia. These findings demonstrate that NSG mice are capable of engraftment of canine PBLs yet develop graft versus host disease similar to Hu-PBL-SCID mice.  相似文献   

13.
Sheep peripheral blood lymphocytes have been studied using a number of surface markers. Thus 16.6 ± 2.4% (mean ± S.E.) were surface immunoglobulin positive (sIg+) by direct immunofluorescence, 35.9 ± 2.1% formed Fc rosettes with bovine red blood cells (RBC) sensitized with rabbit antibody (Fc+) and 28.4 ± 2.0% formed rosettes with sheep red blood cells (RBC) in the presence of 4% dextran (DS+). The percentage of both Fc+ and DS+ lymphocytes tended to increase with age of the animals. Demonstration of these markers allowed computation of two further subpopulations: null cells lacking sIg and a receptor for sheep RBC, and Fc·null cells lacking a receptor for Fc and sheep RBC. The former population, which contained a proportion of Fc+ lymphocytes comprised 49.8 ± 3.8% of blood lymphocytes and the latter 38.4 ± 3.0%.Separation on nylon wool columns, selective rosette enrichment and depletion on density gradients and stimulation with phytomitogens have shown sIg+ and Fc+ lymphocytes to be nylon wool adherent and unresponsive to phytohaemagglutinin (PHA) and Concanavalin A (Con A) and DS+ lymphocytes to be nylon wool non-adherent and responsive to PHA and Con A. The data also indicates a major overlap of the lymphocyte subpopulations bearing sIg and Fc which are apparently B lymphocytes. Moreover these data support the contention that E-rosette formation with sheep RBC in the presence of dextran is a marker for sheep T cells. The data also indicates that Fc·null cells are T cells, eluting in the non-adherent fraction from nylon wool. It is probable that a proportion of these cells bear a SRBC receptor too weak for present detection methods.  相似文献   

14.
Early diagnosis of MAP infection is a pressing need to enable efficient intervention with the spread of MAP infection in herds. Hence, study of lymphocyte subsets and their expressed adhesion molecules could contribute in defining a distinct diagnostic marker (or markers) at the subclinical period of the infection that could in turn facilitate the development of effective diagnostic approach. In accordance with this objective, milk and blood samples were collected from two groups of cattle naturally infected with MAP and their corresponding negative controls. Group (C) comprised 3-4 year-old ELISA negative/PCR positive-cattle that were considered as subclinical seronegative low shedder group (early stage). Group (A) included 6-8 year-old ELISA positive-cattle, which were considered as a clinical seropositive group (late stage). Flow cytometry of B cells, CD8+, CD4+ and γδ cells and the adhesion molecules CD44+, CD62L, LFA-1 and LPAM-1 indicated increase in CD4+ and B cells levels, with higher levels in blood than milk of group A, and significant expression of CD44+ in blood and milk and LPAM-1 in blood only. The CD8+ cells count in milk was higher than blood in the late stage. The peculiar feature of the early stage (group C) was the high level of γδ cells in the blood and milk, with tendency to express high level of CD62L. Compelling evidence could support the assumption that the dominant γδ cells at early stage of MAP infection could be of CD8CD2−WC+1+ phenotype. γδ cells appear as promising markers in defining early changes of MAP infection due to their important role in priming innate and cell mediated immunity. Possible utilization of these peculiar changes in the γδ cells level in the early diagnosis of MAP infection should be the subject of further research.  相似文献   

15.
Objective: To determine whether in healthy horses and those with colic, exposure of peritoneal fluid to room air affects values obtained on biochemical analysis. Study Design: Prospective study. Animals: Adult horses with a primary complaint of acute abdominal pain (n=29) and 12 healthy horses. Methods: Peritoneal fluid was aseptically collected under aerobic and anaerobic conditions. After collection, pH, PCO2, PO2, HCO3?, Na+, ionized Ca2+, K+, lactate, and glucose were immediately measured using a commercial blood gas analyzer. Biochemical variables were compared between aerobically and anaerobically obtained samples using a paired t‐test. Results: In healthy horses, peritoneal fluid samples collected under anaerobic conditions had higher PCO2 and ionized Ca2+ and lower PO2, HCO3?, and pH compared with samples exposed to air. No differences were observed for K+, Na+, glucose, and lactate. In horses with colic, samples collected anaerobically had higher PCO2, ionized Ca2+, Na+, and glucose and lower PO2, HCO3?, and pH value compared with samples exposed to air. No differences were observed for K+ and lactate. Conclusion: Exposure of peritoneal fluid to room air had a significant effect on pH, PCO2, PO2, and variables associated or dependent on changes in pH such as HCO3? and ionized Ca2+. Interpretation of biochemical analysis of peritoneal fluid may be influenced by sample collection method.  相似文献   

16.
In the present study E. coli strains isolated from the faeces of ten horses with diarrhoea and 14 horses without diarrhoea were characterized. All horses were culture negative for Salmonella species. Nine colonies of E. coli from each faecal sample were picked at random and a DNA fingerprint was made by means of a polymerase chain reaction (PCR) using Enterobacterial Repetitive Intergenic Consensus (ERIC) primers. The number of E. coli genotypes did not differ significantly between horses with and without diarrhoea. In addition, all E. coli strains with different DNA fingerprints were tested by PCR for genes encoding the virulence factors K88, F41, F17, CS31a, Sta1, LT1, VT2, CNF, BFP, and intimin. Genes coding for K88, F41, BFP, STa1, VT2, and CS31A were not detected. Genes for CNF were found in strains from one horse with diarrhoea and one horse with normal faeces. Genes for LT1 (n=1) and intimin (n=1) were found only in strains from horses with normal faeces. Genes for F17 fimbriae were found in strains from three horses with diarrhoea (30%) and in none of the strains from healthy horses. In two of these horses, E. coli strains with different DNA polymorphism patterns were F17 positive; however, none of these strains possessed LT1, Sta1, or CNF genes. Haemolytic E. coli strains were only isolated from two horses with diarrhoea and from none of the healthy horses. Nineteen percent of all E. coli strains did not ferment lactose. Eight per cent of these lactose-negative strains were from horses with diarrhoea, whereas 32% were from horses without diarrhoea. In conclusion, virulence factors were present in E. coli isolates from horses with and without diarrhoea, except for F17, which was only found in E. coli isolated from horses with diarrhoea. F17-positive E. coli might have importance as cause of diarrhoea in horses, but further studies are needed.  相似文献   

17.
AIM: To investigate the effects of lolitrem B intoxication on renal K+ secretion in response to increased tubular flow rates.

METHODS: Results are derived from a repeated measure pilot study of seven horses fed non-perennial ryegrass feed for a week prior to exposing them to perennial ryegrass seed and hay that contained an average of 2 ppm lolitrem B. At the end of the control and treatment period frusemide (1 mg/kg I/V) was administered and serial fractional excretion of K+(FEK+) and fractional excretion of Na+(FENa+) calculated. Baseline concentration of aldosterone in plasma, serum K+concentration and feed K+ concentration were also compared.

RESULTS: Key findings included a reduced change in FEK+ from 0 to 15 minutes in response to frusemide administration (p=0.022, Wilcoxon signed-rank test) and a reduced baseline concentration of aldosterone in plasma (p=0.022, Wilcoxon signed-rank test) during the treatment period compared with the control.

CONCLUSIONS: Results suggest that lolitrem B intoxication reduced flow-mediated K+ secretion and interfered with aldosterone production or secretion. However, further investigation is required to validate these findings and to further elucidate the underlying pathophysiology.

CLINICAL RELEVANCE: Lolitrem B intoxication in horses may cause disruption to electrolyte handling in addition to neurological deficits.  相似文献   

18.
A 21‐year‐old pony gelding presented for a 5 week history of diarrhoea, inappetance, progressive weight loss and lethargy. Differential diagnoses for chronic diarrhoea and weight loss in horses include: chronic salmonellosis, sand enteropathy, enterolith, parasitism (strongylosis, cyathostomiasis), NSAID induced ulcerative colitis, inflammatory bowel disease (granulomatous, lymphocytic‐plasmacytic or eosinophilic enterocolitis), gastrointestinal neoplasia (lymphosarcoma, squamous cell carcinoma), antibiotic associated clostridial overgrowth, altered diet or bacterial fermentation, peritonitis, Strongylus vulgaris induced arteriopathy (now quite rare) and abdominal mass or abscess. In this gelding, ante mortem diagnosis of CD3+ intestinal large granular lymphoma was made via cytology of abdominal fluid and immunohistochemistry of a rectal muscle biopsy. This report details the clinical, cytological and immunophenotypic findings of a case of large granular lymphoma in a horse.  相似文献   

19.
Twenty-four coccidia-free goats were reared artificially in indoor cages and allocated to 6 groups of 4 animals each. At 20 days of age, goats in groups 1–3 received 104,105 and 106 sporulated oocysts of Eimeria ninakohlyakimovae per goat, respectively, each as a single dose. Goats in group 4 received daily doses increasing over a 3-week period, starting with 100/day for the first week, followed by 1000, and 10 000/day in weeks 2, 3, respectively. Goats in group 5 received 104 oocysts following a challenge dose of 106 oocysts on day 32. Goats in group 6 were kept as uninoculated controls. Infected animals showed diarrhoea and weight loss. Goats in group 4 showed longer periods of diarrhoea and patency than other infected goats. Goats in group 5 showed the same severe clinical signs as those in group 3 but produced very low oocyst output after a challenge dose. The diarrhoea was associated with a reduction in alkaline phosphatase activity and increases in packed cell volume and haemoglobin. No significant differences were found in serum aspartate aminotransferase, alanine aminotransferase, total protein, albumin, globulin, Na+, K+,Cl− between groups during 48 days after inoculation. There were no serum enzyme indications of damage to the liver. Histological examination performed 100 days after inoculation revealed that inoculated goats had mild subacute to chronic proliferative enteritis in the lower small intestine and the large intestine, and the mesenteric lymph nodes, gallbladders and livers also showed slight histological lesions. The results showed that E. ninakohlyakimovae was highly pathogenic.  相似文献   

20.
The purpose of this, trial was to determine the effect of hyperkalemic periodic paralysis (HYPP) on exercise tolerance in Quarter Horses. Five HYPP affected and five nonaffected horses were matched for age, size, gender and reproductive status. HYPP status was diagnosed by DNA analysis and potassium chloride challenge testing. Plasma lactate concentration and heart rate were used as indicators of work intensity. Serum potassium concentrations were also monitored. Two exercise experiments were conducted, the first being forty-five minutes of slow, aerobic exercise (hacking) and the other being moderate, partially anaerobic exercise (galloping). Post-exercise the horses were cooled out by randomly assigning them to either forty minutes, of standing still or forty minutes of walking. Heart rates of HYPP affected and unaffected horses were not significantly different during exercise or recovery. Plasma lactate concentrations changed slightly following slow exercise and were significantly higher for HYPP affected horses (P=0.01).At the end of exercise, values were 1.4±0.2 mmol/L and 1.0±0.1 mmol/L for HYPP affected and unaffected horses, respectively. Following moderate exercise, plasma lactate concentrations were much greater, and the difference (P<0.001) between affected and unaffected horses was more marked: immediately following exercise concentrations were 10.6±1.8 and 6.2±1.0 mmol/L in affected and unaffected horses, respectively. The higher post-exercise plasma lactate concentrations in affected horses indicates increased anaerobic muscle metabolism. Serum potassium concentrations rose following exercise and significantly higher values were seen in horses that were walked rather than stood still post-exercise.Hyperkalemic periodic paralysis (HYPP) is a dominant autosomal genetic defect occurring in American Quarter Horses and related breeds. 1–5 The condition is widely geographically distributed and has been estimated to affect 0.4% of all Quarter Horses.6 Signs include sporadic attacks of muscle fasciculation, muscle spasm, sweating and weakness. Oral administration of potassium chloride produces a more severe hyperkalemia in HYPP affected horses and induces clinical attacks.1 Electromyography reveals widespread continuous, spontaneous, muscle contraction.2 Some people believe that HYPP affected horses are suitable for riding7; others have expressed doubts about the safety of this practice and the exercise tolerance of affected horses. HYPP affected horses have an unstable muscle membrane potential causing random muscle fiber contractions,2,8 which could antagonize purposeful movement. This, in combination with increases in extracellular potassium concentration occurring during exercise,9–11 may cause affected horses to stumble or collapse while being ridden, posing a danger to both horse and rider. In HYPP affected people, potassium concentration rises approximately one to two hours after exercise during which time HYPP attacks can occur.9,10 For these reasons, the exercise tolerance of HYPP affected horses and the effects of exercise on spontaneous HYPP attacks deserves investigation.We standardized the exercise test and chose heart rate and plasma lactate concentrations as indicatoors, of exercise tolerance and energy metabolism.12 Heart rate is the major determinant of oxygen delivery to muscle and the rate rises with exercise intensity until it reaches a plateau at high velocities.13,14 Several lines of investigation indicate that plasma lactate concentrations reflect muscle work. Lactate release from resting muscle is minimal but large amounts are released during strenuous exercise.15–17 Lactate release increases with increasing muscle work.16,18 During exercise, muscle oxygen consumption increases until eventually a plateau is reached after which no further increase in oxygen consumption in response to increased work loads is possible.18 At this point the mitochondrial electron chain transport system is operating at its maximal possible rate, energy production can only be supplemented by the use of inefficient anerobic glycolytic metabolism and the muscle starts to release lactate. If the concentrations of plasma lactate are high, the muscles are depending on anaerobic metabolism and are working closer to exhaustion16,18–21The objectives of this experiment were twofold. One was to determine if HYPP adversely affects exercise performance. The second was to study the effects of cooling out, by either standing still or walking, on serum potassium and plasma lactate concentrations.  相似文献   

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