Effect of anemia on various reactions of the domestic swine due to physical exertion. I. Initial values and characteristics of anemia]

In six anaemic and six healthy pigs at rest the following values were determined:--rectal temperature, heart rate, respiratory rate, haemoglobin (Hb), haematocrit (Hk), total haemoglobin (THb), plasma volume, blood volume, plasma osmolarity, lactic acid and glucose content of plasma, blood pH, carbon dioxide tension and base excess. There were significant differences between anaemic and normal pigs in Hb, THb, relative THb, Hk, mean cell haemoglobin concentration, lactic acid content; in the ECG there were differences in QT and ST intervals and the ratio of diastole to systole.     

Effect of anemia on various reactions of domestic swine due to physical exertion. 4. Changes of serum acid-base equilibrium]

Carbon dioxide tension, pH and the excess of base were determined in blood samples obtained from the posterior vena cava of six healthy and six anaemic pigs subjected to ten minutes of exercise on a belt moving at 78 m/min at 22-24 degrees C and relative humidity of 55-65%. The fall in these values during physical exertion was greater in anaemic than in healthy pigs. The roles of buffering capacity and rise in body temperature, and the relationship between blood lactic acid and base excess were discussed.     

Effect of anemia on various reactions of the domestic swine due to physical exertion. 3. Changes in plasma glucose and lactic acid concentrations]

Six anaemic and six healthy pigs were exercised for ten minutes on a belt moving at 78 m/min. Initial blood glucose values in healthy pigs averaged 71.2 mg/100 ml, and they changed very little during and after exercise. Initial values were similar in anaemic pigs (70.7 mg/100 ml), but they increased continuously, during exercise, reaching a peak of 157.4 mg/100 ml one minute after the end of exercise. Blood lactic acid increased from 1152 to 2463 mmol/litre in healthy pigs during the first minute of exercise, and then fell gradually. In anaemic pigs it increased from 1652 to 8478 mmol/l during the ten minutes of exercise, and then fell gradually. Correlations between lactic acid and haemoglobin content, between rectal temperature and Hb, and between lactic acid and changes in rectal temperature were discussed.     

Lactic acid content of blood plasma in domestic swine of various breeds during physical exertion]

Lactic acid was determined by an enzymic method in plasma samples taken from 20 pigs of the German Edelschwein, German Landrace, German Saddleback and Edelschwein/Landrace crosses before, during and after being made to run on a band moving at 1.3 metres/second for ten minutes, at 10 degrees C and relative humidity of 65-75%. A special method was used to assess the degree of exertion. The lactic acid curve showed that Edelschwein and German Saddlebacks had a low regulatory capacity while German Landrace and the crossbred pigs had a large capacity. For assessing differences attributable to individuals or to breeds, the occurrence of the maximum lactic acid concentration during or after exercise was of special significance.     

Effect of the type of management and training on heart rate, rectal temperature and respiration rate of domestic swine during physical exertion]

29 pigs (meat type of German Landrace) were kept in groups in a confined space (0.48 m2 a head; group E), in a normal area (1.2 m2 a head; group N) or in a normal area plus daily exercise (group L). After having been kept under these conditions for specified periods, the pigs were made to run on a band moving at 1.1 metres a second for 2 km. During exercise the heart rate increased to 275 beats a minute in group E and only 180 in group L. In group L the recovery pulse rate was greater and the absolute and relative heart weight smaller than in group L; rectal temperature after exercise was also higher than in group L. Values for group N lay between those of groups E and L. The relationship of respiration rate to rectal temperature after exercise was greater in group L than in groups E and N. Physical fitness of groups E and N was inferior to that of group L.     

Evaluation of blood glucose concentration during exertion. 6. Effect of anemia on the glucose regulation capacity of domestic swine in standardized running exercise]

Individual mean blood glucose values and the scatter of individual values were determined in six healthy and six anaemic pigs before, during and after ten minutes of exercise on a belt moving at 78 m/min (environmental temperature 22-24 degrees C, relative humidity 55-65%). The glucose regulatory capacity of anaemic pigs was inferior to that of healthy pigs. Blood glucose regulation was related to haemoglobin content and to the increase in rectal temperature during exercise.     

Glucose concentration in blood during exertion. 5. Use of the total distribution of blood glucose values during physical exercise or the estimation of response to exertion in various breeds of swine]

Blood glucose was determined by an enzymic method in 56 pigs of the German Edelschwein, German Landrace, German Saddleback breeds and Edelschwein/Landrace crosses before, during and after exercise on a belt moving at 1.3 metres/second for ten minutes, at 10 degrees C (winter) or 22-34 degrees C (summer) and relative humidity of 65-75%. Total plasma glucose was calculated from the plasma volume. Total scatter of values for blood glucose concentration and total plasma glucose was greater in Edelschwein and Saddlebacks than in Landrace and the crossbred pigs. There was a close and significant relationship between individual regulatory capacity and breed. The total scatter of blood glucose values was greater in winter than in summer.     

Gas metabolism and body temperature during submaximal, maximal and supramaximal physical activity of swine

VO2, VCO2, gas exchange ratio (R = VO2/VCO2), and rectal body temperature were continuously measured on 6 young fattening pigs and 16 boars during repeated runs (0.7, 1.3, and 2.5 m/s-1) on a horizontally moving belt. Close correlations, almost linear, were found to exist between VO2, VCO2, and rectal temperature in situations in which VO2 moved close to its individual maximum as a result of preselected challenge intensity. None of these 3 parameters was increased further and in keeping with turnover, if higher challenge intensities were chosen.     

Morphological changes in the pineal body of domestic swine (Sus scrofa domesticus) depending on light]

The cerebral epiphysis of twelve gilts, aged 6.5 months, was histologically, histochemically, and histometrically tested, after the animals had been kept permanently under artificial light, 100 lux, or in darkness, interrupted twice a day by two hours of lighting, over ten weeks altogether. The parenchymal cells of the epiphyses of the animals kept in darkness changed clearly from those of the other group with constant exposure to light. Changes in the darkness animals included significant enlargement of the cell nuclear volume by 33 per cent, increase in nucleoli count as well as increases of lipids and ribonucleic acid in cytoplasm.