Monitoring the bovine fetus during stage II of parturition using pulse oximetry

Measurement of oxygen saturation using pulse oximetry is an established method of continuous monitoring of the well-being of the human fetus during parturition. In veterinary medicine, pulse oximetry has been used almost exclusively in intensive care and anesthesiology. The goal of the present study was to investigate the physiological changes in oxygen saturation of the bovine fetus during stage II of parturition and to determine whether the findings can be used to predict postnatal acidosis. The correlation between the oxygen saturation (SpO(2)) measured via pulse oximetry and the oxygen saturation (SaO(2)) of arterial blood measured via blood gas analysis was determined in 23 newborn calves. In addition, the oxygen saturation was monitored continuously via pulse oximetry (FSpO(2)) in 33 bovine fetuses during stage II of parturition. Correlations between the FSpO(2) values during the last 30 and 5min of stage II of parturition and the postpartum values for pH, partial pressures of oxygen and carbon dioxide, bicarbonate concentration, BE, SaO(2) and lactate concentration in arterial blood were determined. There was a high correlation between SpO(2) and SaO(2) postpartum (r=0.923). The FSpO(2) values correlated moderately with the pH and BE and weakly with the lactate concentration postpartum; calves with a pH5.4mM/L had significantly lower FSpO(2) values than non-acidotic calves. FSpO(2) values <30% for a period of at least 2min had the highest predictive value for a calf born with a pH<7.2. Pulse oximetry is a novel method of monitoring the bovine fetus during parturition; however, technical modifications are required to improve its usefulness

Laparoscopic ovariectomy in standing cows

The main objective of this study was to evaluate laparoscopic ovariectomy and to develop an optimal surgical technique for this procedure in standing cattle. Eight cows underwent laparoscopic ovariectomy. In two cows, a bilateral flank approach was used and in six cows, both ovaries were removed via a left flank approach. An important prerequisite for ensuring sufficient intrabdominal space for instrumentation, optimal endoscopic orientation and easy access to the ovaries and uterus was withholding feed for at least 36 h prior to surgery. The cows were sedated with xylazine and the portal sites infiltrated with lidocaine. The portal for the laparoscope was at the ventral angle of the left paralumbar fossa, approximately 10 cm cranioventral to the tuber coxae. The instruments were inserted through two portals approximately 20 cm and 30 cm ventral to the tuber coxae. After abdominal insufflation with carbon dioxide, the left ovary was grasped and local anesthetic was injected into the mesovarium and mesosalpinx. The mesovarium was transected using bipolar cauterization and the ovary removed through an extended instrument portal. The right ovary was removed in the same way. The incisions were closed with single interrupted absorbable sutures in the musculature and single interrupted non-absorbable sutures in the skin. The procedure lasted 120-150 min. Bilateral laparoscopic ovariectomy via left flank approach in standing cows is feasible. This procedure involves special instrumentation, but is minimally invasive and allows optimal visualization of the ovaries and uterus

Einsatz einer GnRH-Vakzine bei Stute und Hengst zur Beeinflussung von unerwünschtem Verhalten: Eine retrospektive Studie von 31 Fällen

Ziel dieser Studie war es, die Wirkung einer GnRH-Vakzine (Equity®) auf das Verhalten und die Gonadenfunktion von Pferden mit unerwünschtem Verhalten zu untersuchen. Anhand eines Fragebogens wurden der Grund für die Behandlung erfragt, sowie die Befunde der klinischen, rektalen palpatorischen und ultrasonographischen Untersuchungen und das Verhalten von 21 Stuten und 10 Hengsten vor und nach der zweimaligen Verabreichung der GnRH-Vakzine miteinander verglichen und das Auftreten von unerwünschten Nebenwirkungen dokumentiert. Bei 84 % der Fälle konnte eine Verminderung des störenden Verhaltens festgestellt werden. Bei den Stuten waren die Ovarien nach der Impfung signifikant kleiner als vor der Impfung (p ≤ 0.05). Auch der grösste sowie der zweitgrösste Follikel auf den Ovarien waren signifikant kleiner nach der Impfung (p ≤ 0.05). Bei den Hengsten konnte kein signifikanter Unterschied in der Hodengrösse vor und nach der Impfung festgestellt werden. Die Studie konnte zeigen, dass die Vakzine für Pferde gut verträglich ist. Nur in 6.5 % der Fälle traten geringe lokale Nebenwirkungen auf. Schlüsselwörter GnRH-Vakzine - Gonadenfunktion - Hengst - Stute - Verhalten The aim of this study was to investigate the effect of a GnRH vaccine (Equity®) on behavior and gonadal function in horses with unwanted behavior. The reason for the treatment was asked using a questionnaire and the findings of physical examination, rectal palpation as well as rectal ultrasonography, were recorded. The results of these examinations and the behavior of 21 mares and 10 stallions before the first and after the second administration of the GnRH vaccine were compared. In 84 % of all cases a decrease of the unwanted behavior could be observed. In the mares the ovaries were significantly (p ≤ 0.05) smaller after vaccination than before. The largest and the second largest follicle on the ovaries were also significantly smaller after vaccination. In the stallion there was no significant difference in the size of testicles before and after vaccination. The study showed that the vaccine is well tolerated in horses and only little local adverse reactions appeared in 6.5 % of all cases. Key words behavior - GnRH vaccine - gonadal function - mare - stallio

Influence of long-term treatment with equine somato-tropin (EquiGen®) on gonadal function in stallions with poor semen quality

The aim of the present study was to investigate the spermatogenic and Leydig cell activity in stallions with impaired semen quality after treatment with equine somatotropin. Experiments were performed using 18 adult clinically healthy stallions with poor semen quality which did not pass breeding soundness evaluation. The animals were randomly divided into a treatment (n = 9) and a control (n = 9) group. Over a period of 90 days, nine stallions received a daily intramuscular injection of 10 mg recombinant equine somatotropin (EquiGen, BresaGen Limited, Adelaide, Australia) and 9 control animals were injected with the same amount of physiological saline solution. During and until 2 months after treatment, semen characteristics and daily sperm output as well as plasma testosterone concentrations were determined monthly in all stallions. In addition, testosterone concentration measurement after stimulation with hCG was performed in all animals immediately before and at the end of the treatment period as well as 2 months later. Our results demonstrate that equine somatotropin (EquiGen) given daily in a dose of 10 mg per animal during 90 days had no significant effect neither on plasma testosterone concentrations and hCG-induced testosterone release nor on semen quality parameters in adult stallions with poor semen characteristics

Effects of hypertonic sodium bicarbonate solution on electrolyte concentrations and enzyme activities in newborn calves with respiratory and metabolic acidosis

OBJECTIVE: To determine concentrations of electrolytes, total bilirubin, urea, creatinine, and hemoglobin; activities of some enzymes; and Hct and number of leukocytes and erythrocytes of newborn calves in relation to the degree of acidosis and treatment with a hypertonic sodium bicarbonate (NaHCO(3)) solution. ANIMALS: 20 acidotic newborn calves with a blood pH or = 7.2. PROCEDURES: Approximately 10 minutes after birth, acidotic calves were treated by IV administration of 5% NaHCO(3) solution. The amount of hypertonic solution infused was dependent on the severity of the acidosis. RESULTS: Treatment resulted in a significant increase in the mean +/- SEM base excess from -8.4 +/- 1.2 mmol/L immediately after birth to 0.3 +/- 1.1 mmol/L 120 minutes later. During the same period, sodium concentration significantly increased from 145.3 +/- 0.8 mmol/L to 147.8 +/- 0.7 mmol/L. Mean chloride concentration before NaHCO(3) administration was significantly lower in the acidotic calves (99.6 +/- 1.1 mmol/L) than in the control calves (104.1 +/- 0.9 mmol/L). Calcium concentration in acidotic calves decreased significantly from before to after treatment. Concentrations of potassium, magnesium, and inorganic phosphorus were not affected by treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of hypertonic NaHCO(3) solution to acidotic neonatal calves did not have any adverse effects on plasma concentrations of several commonly measured electrolytes or enzyme activities. The treatment volume used was smaller, compared with that for an isotonic solution, which makes it more practical for use in field settings

Blood gas analysis of bovine fetal capillary blood during stage II labor

The aim of this study was to determine whether blood gas variables in fetal capillary blood during the last 30 min of stage II labor can be used to diagnose fetal asphyxia. Twenty-five newborn calves were used to investigate the correlation between capillary blood gas values obtained from the dorsolateral aspect of the distal pastern and those in arterial and venous blood. The pH, partial pressure of oxygen, partial pressure of carbon dioxide, concentration of bicarbonate, base excess and oxygen saturation were determined. The bicarbonate concentration (arterial, r=0.759; venous, r=0.766; both P<0.0001) and base excess (arterial, r=0.730; venous, r=0.807; both P<0.0001) had the highest correlations. Fetal capillary blood was collected during the last 30 min of stage II labor and the results of blood gas analysis were compared with those of arterial and venous blood collected immediately after birth in 38 calves. The pH (arterial, r=0.806; venous, r=0.885; both P<0.0001) and base excess (arterial, r=0.822; venous, r=0.871; both P<0.0001) had the highest correlations. The pH and base excess were significantly lower after birth than during the last 30 min of stage II labor. The severity of fetal acidosis during stage II labor can be easily and reliably determined using the pH or base excess of fetal capillary blood

Electrolytes in bovine prepartum mammary secretions and their usefulness for predicting parturition

Accurately predicting parturition in cows can be difficult because of the variability in gestation length and uncertainty of the time of parturition. The goal of the present study was to determine the electrolyte concentrations of prepartum mammary secretions of gravid cows and to investigate retrospectively the possible predictive relationships between these concentrations and the time of parturition. Twenty-three cows were sampled once daily for 3 to 12 d before they calved. The concentrations of calcium, inorganic phosphorus, chloride, magnesium, sodium, and potassium were determined by photometric methods. In addition, the concentrations of calcium, magnesium, and inorganic phosphorus were determined using rapid test kits. The correlation between the photometrically measured electrolyte concentrations and the time of parturition was highest for inorganic phosphorus (r = 0.74). The inorganic phosphorus concentration was 11.8 to 26.5 mmol/L in cows that calved within 24 h of sample collection. When 11.8 mmol/L was used as a cutoff concentration for inorganic phosphorus, 21.7, 47.8, and 87.0% of cows calved within 24, 48, and 72 h, respectively. Within 12 d prepartum, the time of parturition can be estimated, with an error of +/- 32.4 h, by using the results of simultaneous determination of inorganic phosphorus and sodium concentrations in mammary secretions and a formula derived from a multiple regression analysis. The results of a phosphate field test positively and significantly correlated with those of the photometric analysis (r = 0.69) and the time of parturition (r = 0.41)

Blood gas and acid-base analysis of arterial blood in 57 newborn calves

The pH, partial pressure of oxygen (pO(2)), partial pressure of carbon dioxide (pCO(2)), concentration of bicarbonate (HCO(3)(-)), base excess and oxygen saturation (SO(2)) were measured in venous and arterial blood from 57 newborn calves from 55 dams. Blood samples were collected immediately after birth and 30 minutes, four, 12 and 24 hours later from a jugular vein and a caudal auricular artery. The mean (sd) pO(2) and SO(2) of arterial blood increased from 45.31 (16.02) mmHg and 64.16 (20.82) per cent at birth to a maximum of 71.89 (8.32) mmHg and 92.81 (2.32) per cent 12 hours after birth, respectively. During the same period, the arterial pCO(2) decreased from 57.31 (4.98) mmHg to 43.74 (4.75) mmHg. The correlation coefficients for arterial and venous blood were r=0.86 for pH, r=0.85 for base excess and r=0.76 for HCO(3)(-). The calves with a venous blood pH of less than 7.2 immediately after birth had significantly lower base excess and HCO(3)(-) concentrations for 30 minutes after birth than the calves with a venous blood pH of 7.2 or higher. In contrast, the arterial pO(2) was higher in the calves with a blood pH of less than 7.2 than in those with a higher pH for 30 minutes after birth