Cardiopulmonary reference standards in the pregnant sheep (Ovis aries): a comparative study of ovine and human physiology in obstetrics.

1. Complete blood counts, respiratory rate, tidal volume, arterial and mixed venous blood gases; heart rate, cardiac output, and arterial, pulmonary artery, central venous and pulmonary wedge pressures were determined in 10 pregnant adult sheep of 42.7-65.7 kg body weight. 2. Arithmetic means, standard deviations, and coefficients of variation were calculated to develop reference values; in addition, the 95% confidence limits for ranges were established. 3. Comparison of derived data with that from non-pregnant sheep shows changes similar to those seen when examining pregnant and non-pregnant humans. 4. These results indicate the pregnant sheep is an acceptable model for human obstetrical research.     

Blood gas,cardiopulmonary, and urine electrolyte reference values in the pregnant yellow baboon (Papio cynocephalus)

We measured urine sodium and potassium; respiratory rate, lung water, and arterial and mixed venous blood gases; adult and fetal heart rates; hematocrit, plasma sodium and potassium; cardiac output; and arterial, pulmonary artery, central venous, and pulmonary wedge pressures in 13 clinically normal, pregnant yellow baboons (papio cynocephalus). Arithmetic means, standard deviations, and coefficients of variation were calculated to develop reference values; in addition, the 95% confidence limits for ranges were established and regression analyses were performed to determine relationships between parameters. Comparison of derived data with those from published values for nonpregnant baboons indicated differences similar to those seen when examining pregnant and nonpregnant humans.     

Energy and water use by invasive goats (Capra hircus) in an Australian rangeland, and a caution against using broad-scale allometry to predict species-specific requirements

Feral goats (Capra hircus) are ubiquitous across much of Australia's arid and semi-arid rangelands, where they compete with domestic stock, contribute to grazing pressure on fragile ecosystems, and have been implicated in the decline of several native marsupial herbivores. Understanding the success of feral goats in Australia may provide insights into management strategies for this and other invasive herbivores. It has been suggested that frugal use of energy and water contributes to the success of feral goats in Australia, but data on the energy and water use of free-ranging animals are lacking. We measured the field metabolic rate and water turnover rate of pregnant and non-pregnant feral goats in an Australian rangeland during late summer (dry season). Field metabolic rate of pregnant goats (601 ± 37 kJ kg^− 0.73 d^− 1) was 1.3 times that of non-pregnant goats (456 ± 24 kJ kg^− 0.73 d^− 1). The water turnover rate of pregnant goats (228 ± 18 mL kg^− 0.79 d^− 1) was also 1.3 times that of non-pregnant goats (173 ± 18 kg^− 0.79 d^− 1), but the difference was not significant (P = 0.07). There was no significant difference in estimated dry matter digestibility between pregnant and non-pregnant goats (mean ca. 58%), blood or urine osmolality, or urine electrolyte concentrations, indicating they were probably eating similar diets and were able to maintain osmohomeostasis. Overall, the metabolic and hygric physiology of non-pregnant goats conformed statistically to the predictions for non-marine, non-reproductive placental mammals according to both conventional and phylogenetically independent analyses. That was despite the field metabolic rate and estimated dry matter intake of non-pregnant goats being only 60% of the predicted level. We suggest that general allometric analyses predict the range of adaptive possibilities for mammals, but that specific adaptations, as present in goats, result in ecologically significant departures from the average allometric curve. In the case of goats in the arid Australian rangelands, predictions from the allometric regression would overestimate their grazing pressure by about 40% with implications for the predicted impact on their local ecology.     

Selection for nutrients by pregnant goats on a microphyll desert scrub

The behavioral consequences of pregnancy in goats were studied to test the hypothesis that pregnant females on rangeland select a diet richer in nutrients once the demands of gestation increase, and that nutrient content in goat diets changes with the grazing season. A total of 12 mature mixed breed goats either pregnant (n = 6) or non-pregnant (n = 6) were used during the dry period (February to May). Dietary samples obtained from the oral cavity of grazing goats (restrained with a short light rope permanently tightened around their neck) were used for chemical analyses. Across months, pregnant goats selected diets higher (P < 0.01) in crude protein (CP) than non-pregnant goats; this nutrient did not meet the requirements of late gestating goats. Pregnant goats made use of less (P < 0.01) fibrous feeds than non-pregnant goats. In order to cope with changing nutrient demands for pregnancy, goats adjusted their diet by increasing the selection of plants with 32% higher calcium content compared to forages selected by non-pregnant goats. The physiological state of goats did not alter the levels of phosphorus (P), magnesium (Mg) and sodium (Na) in their diets; these minerals were adequate to meet the demands of pregnancy. There were no effects of physiological state on concentrations of copper (Cu), zinc (Zn), manganese (Mn) and iron (Fe) in the goat diets during the dry season, with levels adequate for sustainability of pregnancy. Pregnant goats did not seek forages lower in tannins, alkaloids, saponins and terpenes. It was concluded that to cope with increasing pregnancy costs, goats adjusted their diets increasing selection of forages or plant parts with high nutritional value to maximize their net nutrient budget.     

Pregnancy in goats does not influence intake of novel or familiar foods with or without toxins

Some hypothesize that mammals decrease intake of foods that contain toxins during pregnancy to protect the fetus. We conducted a longitudinal study of feeding behavior to determine if pregnancy-related changes in food selection and intake occurred in goats. Goats eat modest amounts of toxic plants, some of which contain teratogenic or abortifacient compounds, but it is not known if pregnant and non-pregnant goats differ in food selection. The embryo is susceptible to toxins during all stages of pregnancy, but especially so during organogenesis early in pregnancy. Thus, we hypothesized that food selection and intake by pregnant versus non-pregnant goats may differ during various stages of pregnancy. We examined the following predictions that stem from this hypothesis: relative to non-pregnant goats, pregnant goats may alter selection of familiar foods that contain toxins, and of familiar and unfamiliar foods that do not contain toxins. We fed 14 plants with known or probable teratogenic properties during two pregnancies. We also offered beet pulp containing 0.5% LiCl during one pregnancy to test for increased sensitivity to toxins. In addition, we offered novel foods several times during one pregnancy to test for increased food neophobia or neophyllia. Finally, we measured intake of the basal ration by pregnant and non-pregnant goats daily throughout both pregnancies. Both pregnant and non-pregnant goats ate modest amounts of the plants with toxins and of beet pulp with LiCl. Both groups limited intake of novel foods and beet pulp with LiCl to the same degree. Finally, pregnant and non-pregnant goats did not differ in intake (per kg MBW) of the basal ration—dry matter, energy, or protein—in either pregnancy. Thus, the data do not support the notion that goats experienced pregnancy-related changes in food selection or intake.     

Effect of oxytocin on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha during the oestrous cycle and early pregnancy in the goat.

The effect of subcutaneous oxytocin on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin (PG) F2 alpha (PGFM) was examined in the goat at various periods during the oestrous cycle and early pregnancy. 100 i.u. oxytocin was administered daily for 4 day, the dose being divided and given at 0900 and 2100 h; PGFM concentrations were assessed after the first treatment of each day. On days 3-6 (oestrus, day 0) PGFM concentrations increased significantly (P less than 0.001) within 15 minutes and both non-pregnant and mated goats exhibited oestrus behaviour by day 7. Significant (P less than 0.01) increases in PGFM were also produced on days 7-10, in both non-pregnant and pregnant goats, but the responses diminished from day 7 to day 10; only one goat (non-pregnant) came into oestrus. There was a marked difference in response between groups, however, during days 12-15. In non-pregnant goats significant (P less than 0.05) increases in PGFM were detected on days 13-15, but in pregnant animals oxytocin was without effect. Similarly, oxytocin did not increase PGFM concentrations on days 17-20 of pregnancy. However, uterine responsiveness reappeared in pregnant goats with significant (P less than 0.01) increases in PGFM on days 24 and 25.     

Comparison of cardiopulmonary effects of dexmedetomidine administered as a constant rate infusion without loading dose in sheep and goats anaesthetised with sevoflurane

The purpose of this study was to compare the cardiopulmonary effects of dexmedetomidine in anaesthetised sheep and goats. The initial vasopressor effects were prevented by using a constant rate infusion (CRI), without a loading dose.In six sevoflurane anaesthetised goats and sheep dexmedetomidine was infused as CRI (2 μg/kg/h). Before, during and for 30 min after the infusion, cardiac output (CO), systemic and pulmonary arterial pressures, heart rate (HR), respiratory mechanics, inspired and expired gas concentrations, arterial and mixed venous blood gases and the plasma concentration of dexmedetomidine were measured.In goats, CO, HR and mean arterial pressure decreased below baseline values by 20, 40 and 20%, respectively. Systemic vascular resistance (SVR) only decreased after the infusion. Gas exchange and respiratory mechanics remained unchanged. In sheep, CO did not change and SVR decreased progressively up to 45% below baseline. Changes in gas exchange and respiratory mechanics were mild but highly variable. The plasma concentrations of dexmedetomidine were similar in sheep and goats.In conclusion, goats seem to be more sensitive to centrally mediated cardiovascular effects of dexmedetomidine than sheep, which is not related to dexmedetomidine disposition. Adverse pulmonary effects were completely prevented by CRI without loading dose in goats but not in sheep.     

Prostaglandin F2 alpha-induced prolactin release and luteolysis in the goat.

Injection of prostaglandin F2 alpha (PGF2 alpha) initiated a significant increase in plasma prolactin levels in all goats except those in anoestrus. Luteolysis occurred in non-pregnant goats during the mid luteal phase when the goats were given PGF2 alpha either with or without the suppression of prolactin release by bromocryptine (CB154). Luteolysis and subsequent parturition also occurred in pregnant goats in mid and late gestation after PGF2 alpha injection, with an associated release of prolactin and decrease in plasma progesterone. Acute prolactin release in response to injection of thyrotrophin releasing factor may have had a transient effect on plasma progesterone levels, but did not appear to be luteolytic in either pregnant or non-pregnant goats.     

Cerebral Strokes Associated with Pregnancy and the Puerperium

Thirty-one cases of ischaemic cerebral stroke occurring in association with childbirth were fully investigated. The pathological basis of non-haemorrhagic carotid territory strokes in pregnant or puerperal women proved to be similar to that in non-pregnant women of the same age group. Over 70% were due to occlusive cerebral arterial disease or ischaemic lesions unrelated to thrombosis of the intracranial venous system. Comparisons are made with some other reported series in which only a minority of the patients were investigated by angiography, but in which intracranial venous occlusion was assumed to be the primary lesion. It seems likely that many of these patients may also have suffered arterial rather than venous lesions.     

Determination of cardiac output and other reference physiology parameters in lightly anesthetized dogs

1. Cardiac output; arterial, pulmonary artery, central venous and pulmonary wedge pressures; heart rate, hematocrit, and plasma sodium and potassium; arterial and mixed venous blood gases; and respiratory rates were measured in 45 mixed sex, non-pregnant, clinically normal mongrel dogs of 8-30 kilograms body weight following light anesthesia with halothane/50% N20-02. 2. Arithmetic means and standard deviations were calculated to develop tables of reference values. 3. Mean measured cardiac outputs were found to be 31-59% higher in these dogs than the values indicated by published standards; cardiac indices were 30-44% higher; heart rates were 16-30% lower; calculated stroke volumes were 60-112% greater; and total peripheral resistances were 35-57% less than the standard published values. 4. All other measured or calculated parameters fell within previously published canine or human reference limits.     

Circadian variations of plasma renin activity (PRA), aldosterone and electrolyte concentrations in plasma in pregnant and non-pregnant goats

The aim of this study was to estimate and analyse circadian variations of the renin-angiotensin-aldosterone system (RAA) activity in blood of goats and the influence of late pregnancy on the circadian variations of RAA system. The study was carried out on a group of 17 non-pregnant and 9 pregnant goats. The animals were kept in uniform environmental conditions, (9 h light/15 h darkness). Blood samples were collected seven times over a period of 24 h, every 4 h. Plasma renin activity (PRA), plasma aldosterone (PA), sodium, potassium and chloride concentrations were determined. PRA and PA of both groups changed during 24 h, with the highest values in the dark phase and with higher RAA system activity (especially during the night) in the pregnant goats. In the non-pregnant goats, no circadian changes in PRA and PA were observed. The circadian changes in PRA and PA found in pregnant goats had acrophases at 06:27 h and 01:13 h, respectively. Plasma electrolyte concentrations in both groups of goats also changed during 24 h. These results suggest that circadian changes of potassium concentration in plasma of goats during late pregnancy may be one of the main factors affecting the RAA system.     

Influence of pregnancy, lactation and environment on haematological profiles in Danish landrace dairy goats (Capra hircus) of different parity.

1. Haematological analysis was performed in young and adult non-pregnant, non-lactating, early and late pregnant, early mid- and late lactating Danish landrace goats from five herds. The purpose was to determine whether their levels are significantly different in these states and the effect of age and parity on the changes. 2. The haematocrit, haemoglobin concentration, number of erythrocytes and leukocytes were higher in 8-12 month old non-pregnant and 1-2 year old pregnant goats than in adult pregnant and lactating goats of over 2 years of age. Haematocrit, haemoglobin concentration and the number of erythrocytes decreased in late pregnancy and early lactation. 3. At the same time mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration slightly increased. 4. The changes were directly proportional to parity, more in pluriparous than in primiparous goats. 5. After parturition the former group of parameters increased and the latter decreased. 6. There was an increase in the number of total leukocytes close to and after parturition due to neutrophils and lymphocytes and it was more pronounced in the first lactation than in pluriparous goats. 7. There were significant differences in many parameters between goats from different herds (within similar physiological states).     

Prostaglandin production by horse embryos and the effect of co-culture of embryos with endometrium from pregnant mares

Embryos, endometrial biopsies, and uterine lavage fluid were collected from pregnant and non-pregnant mares 14 days after ovulation. Embryos were cultured for 20.5 h with and without endometrial tissue from pregnant mares, and endometrial tissue was cultured alone. Endometrial content of PGF tended to be higher (P = 0.06) in non-pregnant than in pregnant mares, but the amount of PGF released from tissue during culture was similar for pregnant and non-pregnant mares. Lavage fluid from non-pregnant mares also tended (P = 0.08) to contain higher concentrations of PGF. Coincubation of embryos with endometrium from pregnant mares significantly (P = 0.01) lowered concentrations of PGF in medium. Tissue concentrations and release of PGE-2 and 6-keto-PGF-1 alpha were similar in endometrial samples from pregnant and non-pregnant mares and prostaglandin production was unaffected by the presence of an embryo during incubation. Horse embryos released all three prostaglandins during a 20.5-h incubation.     

Continuity of arterial and venous extra-alveolar interstitium in excised rabbit lungs

We studied the interdependence of arterial and venous extra-alveolar vessel (EAV) leakage on the rate of pulmonary vascular fluid filtration (measured as the change in lung weight over time). Edema was produced in continually weighed, excised rabbit lungs kept in zone 1 (alveolar pressure = 25 cmH2O) by increasing pulmonary arterial (Ppa) and/or venous (Ppv) pressure from 5 to 20 cmH2O (relative to the lung base) and continuing this hydrostatic stress for 3-5 h. Raising Ppa and Ppv simultaneously produced a lower filtration rate than the sum of the filtration rates obtained when Ppa and Ppv were raised separately, while the lung gained from 20 to 95% of its initial weight. When vascular pressure was elevated in either EAV segment, fluid filtration always decreased rapidly as the lung gained up to 30-45% of its initial weight. Filtration then decreased more slowly. The lungs became isogravimetric at 60 and 85% weight gain when the Ppa or Ppv was elevated, respectively; when Ppa and Ppv were raised simultaneously substantial fluid filtration continued even after 140% weight gain. We conclude that the arterial and venous EAV's share a common interstitium in the zone 1 condition, this interstitium cannot be represented as a single compartment with a fixed resistance and compliance, and arterial and venous EAV leakage influences leakage from the other segment.     

Pregnancy-specific protein B and progesterone concentrations in French Alpine goats throughout gestation.

The 34 French Alpine dairy goats originated from a single flock and were artificially inseminated 44 h after synchronization of oestrus. They were bled daily at the jugular vein from 15 to 27 days after AI. An early pregnancy diagnosis by RIA of progesterone concentration was performed 21 days after AI. In pregnant goats (greater than 1.5 ng progesterone/ml) daily sampling was extended until 30 days after AI and, from those, 9 were bled every 2 weeks until the end of pregnancy and at 50 and 63 days post partum. Pregnancy-specific protein B (PSPB) was also assayed. The kidding rate was 67.6% (23/34). PSPB concentrations (ng/ml) in pregnant goats were significantly different from those of non-pregnant goats at 24 days after AI (0.82 +/- 0.18 vs 1.78 +/- 0.19; mean +/- s.e.m.) and rose to 40 ng/ml at the end of pregnancy. From Day 25 and throughout gestation, females with 2 fetuses had higher PSPB concentrations than did those with a single fetus (P less than 0.05). In the 2 goats exhibiting late embryonic mortality according to progesterone concentrations, one had a PSPB profile very similar to those of pregnant goats until 30 days while the other did not show any elevation of PSPB concentration. It is concluded that PSPB profiles in goats are similar to those found in cows throughout pregnancy and that PSPB RIA may be useful for pregnancy diagnosis or diagnosis of late embryonic mortality.     

Rate of clearance of immunoreactive hCG from the serum of the pregnant bonnet monkey (Macaca radiata)

The rate of clearance of immunoreactive hCG (human chorionic gonadotrophin) from serum in six pregnant and three non-pregnant monkeys was determined by radioimmunoassay, following the i.v. injection of 2 mg of highly purified hCG. The study revealed that the disappearance of hCG takes place in two phases in both groups, an initial fast (197.5 ± 14.5 min for pregnant and 94 ± 4.8 min for non-pregnant monkeys) phase, followed by a slow (1230 ± 62 min for pregnant and 966 ± 43 min for non-pregnant monkeys) phase. The rate of clearance appears to be faster in non-pregnant than in pregnant monkeys.     

Responses of the uterine circulation to sympathetic nerve stimulation

Pregnant and non-pregnant sheep uteri were perfused in situ with arterial blood at a constant flow rate. Unilateral stimulation (1-2 ma, u ms pulse) of the distal end of the severed sympathetic chain (L3-L4) at frequencies between 5 and 25 Hz produced a graded increase in uterine artery pressure in both horns. At 25 Hz, pressure in the horn ipsilateral to the stimulated sympathetic chain increased by 28 +/ 2% in four pregnant animals and 32 +/ 5% in six non-pregnant ewes. The response of the contralateral horn was significantly smaller than that of the ipsilateral horn (P less than or equal to 0.05). The response was alpha-mediated since it was abolished by local injection of dibenzyline into the middle uterine artery. The responses of the pregnant and non-pregnant animals were similar, indicating that pregnancy did not alter the alpha-adrenergic responses of the uterine vasculature.     

Influence of pregnancy, lactation and environment on some clinical chemical reference values in Danish landrace dairy goats (Capra hircus) of different parity--II. Plasma urea, creatinine, bilirubin, cholesterol, glucose and total serum proteins.

1. Plasma urea, creatinine, bilirubin, glucose, cholesterol and total serum proteins were determined in Danish landrace goats from five herds in early and late gestation, during lactation and in dry goats. The purpose was to determine if there are sustained alterations in the levels of these parameters due to pregnancy and lactation and whether the changes are dependent on age, parity and environment. 2. Urea, creatinine and bilirubin were higher in young non-pregnant goats than in others. Urea decreased in goats at early and mid-lactation directly proportional to parity so that the higher the parity the more the decrease. 3. Creatinine was higher in young and adult non-pregnant goats than in others. There was an increase in late lactation that was greater in goats of higher parity than in others. 4. Bilirubin was higher in the mid-lactation stage, much more in goats of higher parity than in others. 5. Glucose concentration was lower in pregnant than in lactating goats and increased during lactation. The decrease during pregnancy was greater in higher parity goats than in others. 6. Plasma cholesterol and total serum proteins increased during lactation directly proportional to parity. 7. There were significant differences in biochemical parameters between goats from different herds (within similar physiological states). 8. Sustained alterations of these biochemical parameters occur during pregnancy and lactation in goats; the magnitude of changes depends on age and parity, and varies between herds.     

对比分析四维容积超声及彩色多普勒超声在胎儿肺静脉异位引流诊断中的应用

摘要 目的：对比分析四维容积超声及彩色多普勒超声在胎儿肺静脉异位引流（APVC）诊断中的应用价值。方法：采用回顾性分析方法,2019年1月到2022年1月选择在本院进行诊治的胎儿肺静脉异位引流孕妇60例作为研究对象,都给予四维容积超声及彩色多普勒超声,记录影像学特征并判断诊断价值。结果：在60例孕妇中,彩色多普勒超声检查判断为胎儿肺静脉异位引流51例,诊断敏感性为85.0 %;四维容积超声检查判断为胎儿肺静脉异位引流59例,诊断敏感性为98.3 %,四维容积超声检查对胎儿肺静脉异位引流的诊断敏感性明显高于彩色多普勒超声检查（P<0.05）。彩色多普勒超声检查与四维容积超声检查诊断的特异性都为100.0%。在60例孕妇中,判断为胎儿肺静脉异位引流心上型32例,心下型28例;心上型的肺静脉引流途径为肺静脉-垂直静脉-右上腔静脉22例、肺静脉-垂直静脉-左上腔静脉10例,心下型的肺静脉引流途径为肺静脉-垂直静脉-左头臂静脉-右上腔静脉6例、肺静脉-垂直静脉-门静脉22例。合并心脏畸形32例,合并畸形率为53.3 %;有51例孕妇终止妊娠,9例孕妇继续妊娠,其中8例未经治疗者新生儿期死亡,1例在3月龄死亡。结论：相对于彩色多普勒超声,四维容积超声在胎儿肺静脉异位引流诊断中的应用可提高诊断敏感性,可有效反映肺静脉回流情况,可指导临床进行早期干预。     

Pregnancy-associated glycoproteins (PAG) detection in milk samples for pregnancy diagnosis in dairy goats

In ruminants, glycoproteins synthesized in the outer layers of the trophoblast enter the maternal bloodstream. The assay of their concentration in plasma or in serum can be used for pregnancy diagnosis and to indicate feto-placental health status. In this study, concentrations of the pregnancy-associated glycoprotein (PAG) were investigated in the milk of dairy goats. The mean concentrations of PAG in milk were significantly higher in pregnant than in non-pregnant goats throughout the sampling period. Positive milk PAG levels were found in all pregnant animals from Day 32 after breeding, but remained at negative values in nonpregnant ones. This study reports for the first time a pregnancy diagnosis based on milk concentrations of PAG, that could be of great use on the farm.