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1.
Cows and newborn (just after the birth, and on the 1st, 3rd, 5th and 10th days after it) calves were tested for the peculiarities of the electrolyte blood composition and acid-base balance under normal and diarrheic conditions. The values of Na+/K+, Cl-/HCO3-, Pn/Ca2+ ratios in the blood serum of sick animals remain unchanged, which testifies to the deep disturbances of the water-salt metabolism in tissues.  相似文献   

2.
Blood gas and acid-base status was determined in 126 Caesarean-derived calves. The newborn calves were assigned by venous blood pH value at birth to three groups as follows: Group 1 (normal): pH above 7.2; Group 2 (slight acidosis): pH 7.2 to 7.0; and Group 3 (severe acidosis): pH below 7.0. Following Caesarean section births 80 (63.5%) calves had normal acid-base values, while 30 (23.8%) had a slight acidosis, and 16 (12.7%) had severe acidosis. The degree of hypoxia was similar in each group. Six calves (37.5%) in Group 3 died within 48 h of birth. The blood gas and acid-base status of Caesarean-derived. calves was not significantly influenced by any examined parameters with the exception of sex in Groups 1 and 2. The occurrence of meconium-stained calves was 9.1% (n = 11), and only two calves were slightly or severely acidotic immediately after birth.  相似文献   

3.
10 Blood acid-base changes were studied at 17 degrees C in immersed crabs (Carcinus maenas) exposed to hypoxic and hyperoxic conditions, by measuring the pH and the CO2 partial pressure, PbCO2, and by calculating the bicarbonate concentration. 20 Hyperoxia first induces a marked respiratory acidosis with a rise of PbCO2. This acidosis is compensated thereafter by a non-ventilatory increase of the blood buffer base concentration. These results are discussed in relation to the general problems concerning the control of the blood acid-base balance in aquatic animals.  相似文献   

4.
Infection perorally with enteropathogenic E. coli (ST +LT) bacteria in 57 newborn piglets gave rise to watery diarrhoea in 50 (88%) piglets and was lethal in 17 (34 %) cases. The diarrhoea was associated with a progressing partially compensated metabolic acidosis indicated by significantly decreased pH, pCO2 and RE values. The acidosis (BE-values) was significantly correlated with increased blood LA and serum K+ values. The dehydration during the disease was confirmed by increased Hb, Hct, serum protein and urea values as well as loss of weight. The changes were most pronounced in piglets that died and a BE value of —10 mmol/1 seemed to be a critical limit at which the prognosis could be considered poor. The changes in acid-base status and water balance was confirmed in 64 piglets with spontaneous cases of E. coli diarrhoea.  相似文献   

5.
Formation of acid-base homeostasis in newborn calves takes place simultaneously with developing metabolic respiration-excretion and buffer system resulting in fast adaptation of animals to new environmental conditions.  相似文献   

6.
Homeostasis of acid-base condition in newborn calves is ensured with metabolic, respiration--excretion and buffer systems, which allows for fast adaptation of animals to new living condition.  相似文献   

7.
This study investigated the effects of malate supplementation on blood acid-base balance and serum lactate levels in a 137-day feedlot experiment with bull calves. Animals were allotted to one of two experimental groups: (1) A control group (no supplementation), and (2) a group receiving a salt of DL-malic acid. Blood pH, pCO2, HCO3-, base excess, serum L-lactate and productivity parameters were evaluated. Our data reveal that under the conditions of the present experiment malate supplementation did not have any significant effect on productivity parameters by comparison with non-supplemented animals. As regards acid-base balance, no significant effects attributable only to malate were observed. In conclusion, the time-course and the overall means of serum L-lactate for both groups in both growing and finishing periods (0.44 +/- 0.04 mmol/l and 0.39 +/- 0.02 mmol/l, respectively, for control animal; and 0.54 +/- 0.03 mmol/l and 0.49 +/- 0.01 mmol/l, respectively, for supplemented animals) suggests that malate does not have any beneficial effects in animals fed a diet of similar characteristics to that given in this study.  相似文献   

8.
Pregnancy complicated by poor control of diabetes is associated with a higher risk of embryopathies, spontaneous abortions and perinatal mortality. A number of authors suggest an involvement of reactive oxygen species (ROS) in diabetic pregnancy. Determining lipid peroxidation products (LP), scavenging enzyme activities and the umbilical cord blood's acid-base balance may contribute to an adequate diagnosis of the neonate at birth. Nevertheless, such measurements seem to have limited value in practical clinical routine. The present study evaluates LP, antioxidant defence and acid-base status related to diabetic pregnancy. Twenty-eight women with type 1 diabetes (PGDM), 19 with gestational diabetes (GDM) and 13 control cases were investigated. An additional control group consisted of 15 healthy patients with negative diabetic history; all women underwent vaginal delivery. Immediately after delivery cord blood samples and placental tissue were collected for malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) determination. Additionally, pH, pCO2, pO2 and base excess were measured in both vessels and compared to identify and exclude double venous samples. MDA levels in both cord blood and placental homogenates were significantly higher in both pregestational and gestational diabetic groups, but SOD activity was significantly diminished. Cord blood GSH was markedly elevated in PGDM and GDM. We have also shown significant differences in acid-base parameters in infants of PGDM group. Statistical analysis was performed using the Mann-Whitney U-test.These findings indicate an excessive oxidative stress in pregnancy complicated by diabetes mellitus. Evaluating LP products and scavenging enzyme activities may be valuable, sensitive indexes of fetal/neonatal threat in diabetic pregnancy in humans. Since oxidative stress is an important pathway for fetal injury, we believe that obtaining adequate measurements at the time of birth would contribute to clarifying the fetal/neonatal status in a medical and legal context and might be of value in altering therapy in newborn infants.  相似文献   

9.
Panting and acid-base regulation in heat stressed birds   总被引:1,自引:0,他引:1  
1. Studies in respiratory physiology and acid-base balance of panting birds exposed to high Tas show that flying as well as nonflying birds can use the respiratory system simultaneously for gas exchange and evaporative cooling. 2. The present study proves that well acclimated hand-reared birds can effectively regulate a normal CO2 level and acid-base status in arterial blood, when exposed to extremely high temperatures (50-60 degrees C). 3. In many birds practising simple or "flush-out" panting, the dead space can be reduced to a volume which is estimated to be approx 15% the volume of the respiratory tract. 4. These two modes of ventilation, shallow and high-rate, restricted to the nonrespiratory surfaces, may ensure the avoidance of CO2-washout and limit lung ventilation to the volumes needed for oxygen consumption. 5. This view supports earlier theories, suggesting the existence of physiological shunt mechanisms which operate during thermal panting in birds.  相似文献   

10.
The effect of experimental metabolic acidosis and its correction for nitrogen and energy metabolism was studied in new-born calves. It was discovered that a change in the acid-base balance towards acidosis causes a sharp increase in "ammoniogenesis", urea formation and inhibition of the tricarboxylic acid cycle, which is also observed in calves suffering from dyspepsia with symptoms of acute diarrhea. Alongside with the use of therapeutic measures for treating dyspepsia of new-born calves, it is necessary to control the acid-base balance of blood in the calves and in case of revealing the acidosis state to use means of its correction.  相似文献   

11.
This essay will treat, first, the defended parameters of acid-base status in avian blood and their modification under conditions pertinent to the life of birds, and, second, urinary acidification and its role in maintenance of acid-base balance. Of the two topics, urinary acidification is of particular interest to the author, has received less sustained attention experimentally and has been infrequently reviewed (Sykes, 1971), so it will receive attention here. The reports cited in the essay concern primarily adult birds outside periods of egg-laying.  相似文献   

12.
The state of the acid-base balance and of the blood coagulation system was studied in starvation of young (5-6-month-old) and old (24-26-month-old) male rats during starvation. The periods of the maximal changes coincided in both systems; in the young animals the onset of the acidotic crisis and hypercoagulation development occurred earliear and were more pronounced. Old animals proved to be more resistant to the conditions of starvation and died later than the young ones.  相似文献   

13.
As revealed in this study, metabolic acidosis is observed in experimental animals the influence of "murine" toxin and Y. pestis fraction I, which is manifested by the parameters of the acid-base state, the gas composition of blood and the content of electrolytes.  相似文献   

14.
The turnover rate of glucose, the irreversible disposal rate of lactate, and the rate of gluconeogenesis from lactate were calculated by tracer methods in four normal and four alloxan-diabetic dogs under control conditions as well as in chronic, stable metabolic acidosis and alkalosis. Acidosis was produced by feeding dogs 0.8-1 g.kg-1.day-1NH4Cl over 1 week, alkalosis was produced by feeding dogs a chloride-free diet and injections of furosemide. Mean plasma pH in the three states were 7.28 +/- 0.013, 7.40 +/- 0.024, and 7.51 +/- 0.015 in normal dogs, and 7.22 +/- 0.025, 7.42 +/- 0.009, and 7.49 +/- 0.002 in the diabetic dogs. Respective mean plasma bicarbonate levels were 14.6 +/- 0.88, 22.0 +/- 0.80, and 32.4 +/- 1.88 mequiv. in normal dogs, and 12.3 +/- 1.30, 22.6 +/- 0.66, and 35.0 +/- 1.14 mequiv. in diabetic animals. In normal dogs shifts in acid-base balance had no effect on the level of plasma glucose or the turnover rate of glucose. In diabetic dogs plasma glucose level was significantly elevated by alkalosis. Plasma lactate was positively correlated with plasma pH (r = 0.69, p less than 0.01) and was in general higher in diabetic than in normal animals. The increment in concentration was due to a decreased clearance of lactate from the plasma. The irreversible disposal rate was not changed by the acid-base status. Whereas a larger fraction of lactate removed from the plasma appeared in glucose in diabetic animals, this fraction was not changed significantly by shifts in the acid-base status.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
The aim of the present study was to determine the effects of the potential methane reducer fumaric acid on the fattening performance and acid-base balance of growing bulls fed two different silage types as roughage (maize and grass silage). A total of 62 fattening bulls (German Holstein breed, initial body weight: 266 +/- 42 kg), randomly assigned to eight feeding groups, received four levels of fumaric acid (0, 100, 200 or 300 g/d) at each silage type. The daily feed and water intake and the live weight were measured over the whole testing period of 280 days. In blood samples, blood cells and blood gases as a parameter of acid-base status were analysed. Feed and faeces were collected to determine the apparent nutrient digestibility. Five animals from each group fed maize or grass silage, supplemented with 0 g or 300 g fumaric acid, were slaughtered at 580 kg body weight. After slaughter, rumen fluid pH was measured and dressing percentage was calculated. Neither the total feed intake (8.81 +/- 0.07 kg/d) nor the daily weight gain (1277 +/- 24 g/d) was influenced significantly by treatments. Fumaric acid supplementation did not influence the erythrocyte count or the blood gas concentration. The silage type significantly influenced the apparent digestibility of the whole diet. The dressing percentage was slightly higher (p < 0.1) after fumaric acid supplementation. No signs of an incompatibility to fumaric acid on the animals were observed over the whole experimental period. However, it seems to be necessary to conduct more long-term studies with different silage types and addition of organic acids combined with direct measurements of methane.  相似文献   

16.
The effect of ethanol on maternal and fetal blood gases and acid-base balance was determined in six conscious instrumented near-term pregnant ewes for maternal intravenous infusion of 3 g ethanol/kg total body weight administered as six doses of 0.5 g ethanol/kg total body weight over 8 h. Maternal and fetal blood ethanol concentrations, determined in two animals, were maximal at 8 h (3.74 and 3.82 mg/mL, respectively) and were virtually identical during the 24-h study. Maternal and fetal blood gases and acid-base balance were not significantly altered during and after ethanol administration compared with preinfusion values. The data demonstrate that, during near-term ovine pregnancy, the equivalent of a binge-type drinking episode does not produce fetal hypoxia or acidosis. Furthermore, these data do not support the postulated involvement of ethanol-induced fetal hypoxia in the mechanism of ethanol teratogenesis.  相似文献   

17.
Rats exposed to 25 or 300 ppm NH3 vapor for 5-15 days 6 hr daily showed dose-dependent blood ammonia after 5 days. Brain and blood glutamine were also increased at the same time in rats exposed to 300 ppm. The blood ammonia concentration of the exposed rats resumed control levels at 10 and 15 days while hepatic citrulline synthesis increased above that of the controls. The animals exposed to 300 ppm NH3 showed initially a slight acidosis. As circulating ammonia decreased, brain and blood glutamine returned to the control range. Our findings support the idea that ureagenesis is aimed mainly at the removal of NH+4 with only secondary and small effects on the acid-base balance.  相似文献   

18.
In a study of the acid-base changes in the blood of rabbits during and following transfusions of citrated blood and of heparinized blood, it was observed that, with citrated blood, pH decreased and carbon dioxide tensions rose. With heparinized blood, the acid-base balance was maintained within normal limits following transfusions.The potential hazards of rapid massive citrated blood transfusions in the anesthetized patient during operation must be kept in mind.  相似文献   

19.
H. Levison  P. R. Swyer 《CMAJ》1965,92(21):1127-1129
The relation between oxygen consumption, metabolic status and prognosis was studied in two infants with identically low arterial oxygen tensions (20 mm. Hg) due to cyanotic congenital heart disease. The first patient had low oxygen consumption, arterial blood acidosis and increased arterial lactate, and died at the age of 36 hours. The second had normal oxygen consumption, arterial acid-base balance, lactate and pyruvate, and survived. Since arterial oxygen tensions were similar in both, it was concluded that compensatory factors, such as cardiac output, pulmonary and systemic blood flow and increased oxygen saturation at normal pH levels (Bohr effect), are important in maintaining tissue oxidation and preventing anaerobiosis and lactate production. The importance of a knowledge of acid-base status in the immediate prognosis of cyanotic congenital heart disease is stressed. The treatment of acidosis by buffer therapy may be an important palliative, improving cardiac output and tissue oxidation, and should be undertaken as soon as possible before irreversible cellular damage has occurred.  相似文献   

20.
We have recently shown that background presence of chronic metabolic acid-base disorder markedly alters in vivo acute CO2 titration curve. These studies were carried out to assess the influence of chronic respiratory acid-base disorders on response to acute hypercapnia and to explore whether the chronic level of plasma pH is the factor responsible for alterations in the CO2 titration curve. We compared whole-body responses to acute hypercapnia of dogs with preexisting chronic respiratory alkalosis (n = 8) with that of normal animals (n = 4) and animals with chronic respiratory acidosis (n = 13). Chronic respiratory alkalosis and acidosis, as well as the acute CO2 titrations, were produced in unanesthetized dogs within a large environmental chamber. For comparison with our data on chronic metabolic acidosis and alkalosis, plasma bicarbonate levels, which are secondarily altered in chronic respiratory acid-base disorders, were used as an index of chronic acid-base status of the animals. Results indicate that, as with chronic metabolic acid-base disorders, a larger increment in plasma bicarbonate occurs during acute hypercapnia when steady-state plasma bicarbonate is low (respiratory alkalosis) than when it is high (respiratory acidosis). Yet, in further analogy with the metabolic studies, plasma hydrogen ion concentration is better defended at higher plasma bicarbonate levels in accordance with mathematical relationships defined by the Henderson-Hasselbalch equation. Combined results demonstrate that the influence of chronic acid-base status on whole-body response to acute hypercapnia is independent of initial plasma pH.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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