Biomedical subjects

W Baumgartner

Publications and source records attributed to W Baumgartner.

At least 91 records · Page 5Linked to original sources

PubMed1992

[Evaluation of basic feed in dairy cow nutrition].

The basic feeds hay, grass silage and corn silage out of 70 dairy farms were investigated for the correct evaluation of their concentration of raw protein (RP) and gross energy (NEL) lactation. Three different kinds of rations were grouped: type A (estimated feed mass, table data contents), type B (weighed feed mass, table data contents), type C (weighed feed mass, analysed contents). Concerning gross energy lactation significant differences between C and A and C and B could be detected. Calculations of the expected milk yield (Milk Yield Potential, MYP) out of gross energy lactation and of raw protein were carried through and compared, using each, analysis data and table standards. MYP out of raw protein in basic feeds significantly exceeds the possible milk yield out of gross energy concentration, referring to table standards and analysis data as well. Raw protein-MYP of analysed data was significantly higher than of table standards, whereas gross energy MYP calculated with analysed data did not agree with table standards.

Animal Feed↗

PubMed1992

[The effect of the lactation period on the cell content of sheep milk].

Milk samples of 201 ewes were examined in 6 week intervals during a complete lactation period. Those samples were analyzed for the presence of pathogenic bacteria and the somatic cell count was determined. Besides, the California Mastitis Test (CMT) was performed and the udder was clinically examined. The cell counts were found to depend on the lactation period. During 6 weeks following parturition the cell count was 63,000 cells/ml. This number decreased towards the 24th week of lactation to 32,000 cells/ml. At the end of lactation this value increased again to 425,000 cells/ml. The median value of ewes with normal udder health was 56,000 cells/ml milk. For samples from which pathogenic bacteria were isolated this value was 159,000 cells/ml. The most frequent pathogens isolated from the milk samples were coagulase-negative cocci (59.6% of bacteriologically positive samples), the median number being 88,000 somatic cells/ml in these sheep. Coagulase-positive cocci were isolated in 25.3% of the samples, the median value of the cell count was 295,000 cells/ml. In 12.1% of the samples streptococci were found. The median value was 167,000 cells/ml. From the remaining 3.0% of bacteriologically positive samples Pasteurellae, E. coli and Actinomycetae were isolated. The median value of the somatic cell count was 184,000 cells/ml. We consider coagulase-positive cocci therefore as the most pathogenic bacteria for the ovine udder.

Animals↗

PubMed1991

Mechanisms of blood flow during pneumatic vest cardiopulmonary resuscitation.

Mechanisms of blood flow during cardiopulmonary resuscitation (CPR) were studied in a canine model with implanted mitral and aortic flow probes and by use of cineangiography. Intrathoracic pressure (ITP) fluctuations were induced by a circumferential pneumatic vest, with and without simultaneous ventilation, and by use of positive-pressure ventilation alone. Vascular volume and compression rate were altered with each CPR mode. Antegrade mitral flow was interpreted as left ventricular (LV) inflow, and antegrade aortic flow was interpreted as LV outflow. The pneumatic vest was expected to elevate ITP uniformly and thus produce simultaneous LV inflow and LV outflow throughout compression. This pattern, the passive conduit of "thoracic pump" physiology, was unequivocally demonstrated only during ITP elevation with positive-pressure ventilation alone at slow rates. During vest CPR, LV outflow started promptly with the onset of compression, whereas LV inflow was delayed. At compression rates of 50 times/min and normal vascular filling pressures, the delay was sufficiently long that all LV filling occurred with release of compression. This is the pattern that would be expected with direct LV compression or "cardiac pump" physiology. During the early part of the compression phase, catheter tip transducer LV and left atrial pressure measurements demonstrated gradients necessitating mitral valve closure, while cineangiography showed dye droplets moving from the large pulmonary veins retrograde to the small pulmonary veins. When the compression rate was reduced and/or when intravascular pressures were raised with volume infusion, LV inflow was observed at some point during the compressive phase. Thus, under these conditions, features of both thoracic pump and cardiac pump physiology occurred within the same compression. Our findings are not explained by the conventional conceptions of either thoracic pump or cardiac compression CPR mechanisms alone.

Animals↗

PubMed1991

[The cell count in sheep and goat milk].

The udder health of 404 sheep from 23 flocks and 397 goats from 15 herds in Lower Austria was examined. In order to determine cell levels, the Schalm Test (equivalent to the California mastitis test) and a fluoroscopic "Fossomatic" cell count appliance were employed. The resultant physiological median levels of somatic cell content were established as 71,000 cells/ml for sheep milk and 415,000 cells/ml for goat milk. Significant factors influencing the cell count levels were the milking technique in both species and age in sheep but not in goats. The pathogens most frequently isolated as causes of chronic or latent mastitis were coagulase-positive and -negative cocci.

Animals↗

PubMed1990

Is atrial activation beneficial in heart transplant recipients?

Because of the distortion of atrial morphology that occurs during cardiac allograft transplantation in humans, the beneficial effects of properly sequenced atrial and ventricular activation are unclear in these patients. To evaluate the atrial contribution to ventricular pump performance in heart transplant recipients, arterial pressure and cardiac output during pacing from either chamber were measured in nine patients 10 +/- 1 days after transplantation. Systolic, diastolic and mean systemic arterial pressures were significantly higher during atrial pacing compared with ventricular pacing: 143 +/- 23 versus 125 +/- 20 mm Hg, 73 +/- 15 versus 66 +/- 14 mm Hg and 94 +/- 17 versus 84 +/- 16 mm Hg, respectively (p less than 0.05 for all). In addition, cardiac output decreased from 5.5 +/- 1.4 to 4.6 +/- 1.5 liters/min (p less than 0.005) for atrial versus ventricular pacing. Thus, there is a significant atrial contribution to cardiac performance in patients after heart transplantation. This may have clinical implications in those patients who later require a permanent pacemaker.

Atrial Function↗

PubMed1990

[The occurrence and distribution of maedi-visna virus infection in lower Austrian sheep breeding establishments].

In a period of one year blood samples of 374 sheep of Lower Austrian flocks were examined in intervals of two months for antibodies against Maedi-Visna (MV). Further on specific attention was paid to the prevalence of MV-infection in the flocks. The antibody-titers were determined by means of agar gel-immunodiffusion test. In 5 (23.8%) of 21 flocks 45 (12.0%) of the sheep were seropositive. Seroprevalence varied within the examined breeds: 19 (27.1%) of 70 Karakul-sheep, 18 (28.1%) of 64 East-Friesian milk-sheep, 7 (9.4%) of 74 Merino sheep and 1 (0.9%) of 111 mountain sheep. None of 55 black-headed sheep showed MV seropositive reaction. Clinical symptoms of Maedi-disease were especially observed in milk-sheep and for the first time in Austria in Karakul-sheep. Unfavorable housing conditions (insufficient room, bad climatic conditions), breed specific behavior patterns (crowding of Karakul-sheep) and a high prevalence of MV infections promote a high incidence the disease.

Animals↗

PubMed1990

Core cooling remains the most effective technique of extended heart-lung (HL) preservation: further experimental evidence.

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Animals↗

PubMed1990

[Seroepidemiologic studies of the agent of respiratory diseases in cattle].

In a period of three years epidemiological studies were carried out in Styria concerning the occurrence of antibodies against BRSV (Bovine Respiratory Syncytial Virus), Adeno I Species 3-Virus, Adeno II Species 8-Virus, PI-III (Parainfluenza 3-Virus), IBR/IPV-Virus and Chlamydia. A total of 1376 serum samples were examined and showed different titers of specific antibodies against respiratory pathogens. 449 blood samples were submitted to serological examinations in the year 1984, 525 in 1985 and 402 in 1986. Antibodies against BRSV could be found in 17.4% of the sera or in 55.9% of the herds. Specific antibodies against Adeno I Species 3 occurred in 33.9% of the sera resp. in 74.2% of the units. 35.2% of the cows or 80.1% of the herds showed positive SN-titres against Adeno II Species 8. IBR/IPV-specific antibodies were detected in 2.3% of the sera resp. 3.8% of the herds. Antibodies against Chlamydia could be found in 8.8% of the cows or in 22.6% of the units. In the years mentioned above significant differences of antibodies against BRSV, Adeno I Species 3, Adeno II Species 8 and Chlamydia could be observed, but not against PI-III and IBR/IPV as well. By means of the Chi-Square-Test significant differences between Simmentaler, Austrian Brown Cattle and Holstein Friesian regarding antibodies against IBR/IPV and Adeno II Species 8 could be found. No significant differences between the serological results of herds, which contained on of the three breeds could be observed.

Animals↗

PubMed1989

[Risks of intravenous injection into the tail of cattle].

Since several years collecting blood from the tail vessels in bovine practice gained a wider range of propagation. Recently veterinarians tried to inject drugs intravenously into the tail vessels of the bovine tail. Therefore we carried out anatomical studies concerning the position of the blood vessels of the bovine tail. 24 tails of slaughtered cattle, which were of different breeds and age (1-4 years old), were examined in respect to the course of their arteries and veins as well on the ventral side. By means of necropsy, frozen cross sections, corrosion anatomy and radiography the position of the tail vessels to each other were compared. In the area of the 2nd to 7th coccygeal vertebra the position of the arteries and veins were being determined. Following results were obtained: 1. The A. cocc. med. runs always ventral in the midline of the tail. 2. The number of ventral veins proximal on the tail varies from 1 to 3. 3. The course of the Vena(ae) cocc. mediana(ae) in the tail region examined is inconstant. The vein lies either left, right, dorsal or ventral of the A. cocc. med. The vein can also cross the area. 4. In 8 of 19 examined cases the V. cocc. med. was closely left to the artery (area of the 5th coccygeal vertebra). After radiologic examination it can be stated that this region can be used for collecting blood of the V. cocc. med. In case of intravenous application of considerable amounts of drugs into the vein of the tail a certain portion can get easily into the closely attached artery and severe complications, as necrosis of the tail can occur. Therefore our clinic recommends generally the use of the Vena jugularis externa for intravenous injection.

Animals↗

PubMed1989

Negative intrathoracic pressure decreases independently left ventricular filling and emptying.

The mechanism for the fall in left ventricular (LV) stroke volume with normal and obstructed inspiration is controversial with changes proposed in LV preload and afterload. During respiration extending over several cardiac cycles, changes in both LV filling and emptying could occur, rendering demonstration of any responsible mechanism difficult. To evaluate the independent effects of negative intrathoracic pressure (NITP) on LV filling and emptying, we have analyzed the effects of NITP confined to either diastole or systole using electrocardiogram (ECG)-triggered phrenic nerve stimulation in six anesthetized closed-chest dogs. Lung volume was either maintained by completely obstructing the airway or allowed to increase during NITP. With diastolic NITP and the airway obstructed during phrenic nerve stimulation, LV filling volume (integrated mitral flow) significantly decreased (-37 +/- 6.1% SE) associated with increases in LV and right atrial filling pressures at end diastole relative to both atmospheric and esophageal pressures. Right atrial pressure relative to either atmospheric or esophageal pressure increased significantly more than left atrial pressure. The ensuing LV stroke volume (integrated ascending aortic flow) decreased significantly (-30.8 +/- 5.9%). With NITP confined to systole and at constant LV preload, LV stroke volume also decreased (-12.9 +/- 2.5%) associated with an increase in LV systolic pressure relative to esophageal pressure. Similar significant changes were observed despite a smaller fall in esophageal pressure when lung volume was allowed to increase during either diastolic or systolic NITP. We conclude that 1) NITP confined to diastole decreases LV filling and the ensuing LV stroke volume, most likely by ventricular interdependence; 2) NITP confined to systole also decreases LV stroke volume, presumptively by imposing an increased afterload on the LV; 3) both diastolic and systolic mechanisms should contribute to a decreased LV stroke volume during normal and obstructed inspiration; and 4) if the effects of intrathoracic pressure changes were to extend over several cardiac cycles, mechanisms exist to account for either increases or decreases in LV volumes.

Airway Obstruction↗

PubMed1989

[Diaphragmatic eventration in a breeding sow].

A sow of 190 kg weight suddenly died, one day before due to delivery, though seeming to be quite healthy a few hours previously. Pathomorphological investigation revealed a 11 cm wide gap in the diaphragma in the area of the hiatus oesophageus with an eventratio diaphragmatica simplex incarcerata. The pathogenesis is suggested to be a widening of an inborn small gap in the diaphragma through the increase of intraabdominal pressure due to pregnancy and beginning labour.

Animals↗

PubMed1988

Mitral and aortic blood flows during spontaneous respiration in dogs.

Left sided hemodynamic events during respiration remain a controversial subject. Left ventricular (LV) hemodynamic events were evaluated during obstructed and partially obstructed inspiration in anesthetized dogs acutely instrumented with mitral (Qm) and ascending aortic (Qa) flow probes. This allows classification of the inspiratory decrease in LV stroke volume as either a diastolic event (e.g., ventricular interdependence) in which case the LV inflow volume (integral of Qm) should decrease before the LV outflow volume (integral of Qa), or a systolic event (e.g., afterload or contractility) in which case outflow (integral of QA) should decrease before inflow (integral of Qm). During either unobstructed (n =8) or partially obstructed (n = 5 spontaneous ventilation, Qm reached both its inspiratory minimum and expiratory maximum prior to the associated minimum and maximum values for integral of in 80% or more of the respiratory cycles. Thus, a diastolic event dominates both in reducing the subsequent LV outflow during the expiratory increase in intrathoracic pressure. However, because a diastolic event did not occur first at all times, a systolic event must occur first at all times, a systolic event must also be present. If a rapid change in intrathoracic pressure occurred during diastole, integral of Qm invariably immediately increased. If a rapid in intrathoracic pressure occurred during systole, integral of Qa could change independently of the preceding integral of Qm. Both systolic and diastolic mechanisms contribute to the inspiratory fall in LV output. These mechanisms will not be clearly delineated without evaluating the effects of intrathoracic pressure within a single cardiac cycle.

Airway Obstruction↗

PubMed1988

Effects of changes in left ventricular loading and pleural pressure on mitral flow.

The cause of the fall in left ventricular (LV) stroke volume (SV) during a fall in pleural pressure (Pp1) has been in dispute for over a century. We have defined the changes in the temporal relationship between LV inflow (Qm) and outflow (Qa) in a canine preparation to test the mutually exclusive hypotheses that the fall in LVSV is caused only by changes during diastole (e.g., ventricular interdependence) or only by changes during systole (e.g., afterload). The ability of the experimental preparation to measure the results of acute changes in right heart volume or output and acute changes in LV afterload was validated in open-chest studies with and without pericardial constraint. In closed-chest studies, with a fall in Pp1 during a Mueller maneuver Qm reached both its inspiratory minimum and expiratory maximum before Qa in 80% of the Mueller maneuvers, invalidating both hypotheses, which each required that one flow lead the other in 100% of the Mueller maneuvers. Review of individual records suggested that if the rapid changes in Pp1 occurred during systole, Qa could vary in a manner independent of the preceding Qm. These studies suggest that both diastolic and systolic events may contribute to the fall in SV, while causing opposite changes in LV volumes.

Animals↗

PubMed1987