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ObjectiveTo evaluate the cardiopulmonary changes induced by intravenous butorphanol administration in guineafowl anesthetized with sevoflurane.Study designProspective experimental trial.AnimalsEight adult guineafowl (Numida meleagris) weighing 1.61 ± 0.49 kg were used for the study.MethodsBirds were anesthetized with sevoflurane and allowed to breathe spontaneously. After endotracheal intubation, end-tidal sevoflurane was adjusted to 1.0 individual sevoflurane MAC that was previously determined in triplicate using a standard bracketing technique. The brachial artery was catheterized for direct pressure measurement and blood sampling. Heart rate and rhythm were monitored by electrocardiography and respiratory rate was recorded. Baseline data were recorded 30 minutes after induction. Then, end-tidal sevoflurane was adjusted to 0.8 individual MAC and after 15 minutes physiologic variables were measured again. Subsequently, butorphanol (4 mg kg?1) was administered intravenously over 10 seconds and physiologic responses were recorded at 1, 5, 10, 15, 20, 30 and 45 minutes after administration.ResultsButorphanol administration was associated with arrhythmias in all birds, including second-degree atrioventricular block, sinus arrest, ventricular and supraventricular tachycardia and ventricular premature complexes. Heart rate and arterial blood pressures decreased significantly 1 minute after butorphanol administration. Two birds developed severe hypotension, apnea and ventricular fibrillation 5 minutes after administration, and one died.Conclusions and clinical relevanceThe butorphanol dose (4 mg kg?1) that produces clinically relevant sevoflurane MAC reduction in guineafowl caused severe adverse cardiopulmonary effects in two birds and was considered unsafe under the conditions used in this study.  相似文献   
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The aim of this study was to investigate the effects of different concentrations of oral supplementation with selenium (Se) upon ram sperm parameters. Thirty rams managed in stall under intensive system were used and divided into five groups (six animals per group) as follows: control group (G1) mineral mixture supplementation without Se, group 2 (G2) mineral mixture supplemented with 5 mg/kg Se, group 3 (G3) supplemented with 10 mg/kg Se, group 4 (G4) supplemented with 15 mg/kg Se and group 5 (G5) supplemented with 20 mg/kg Se. For each group, there was an adjustment period of 14 days. The experimental period was 350 days. Every 56 days, the animals were weighed and semen samples were collected by electroejaculation. Semen analysis included volume, mass moviment, total motility, vigour, concentration and morphology. For plasmatic and acrosomal membrane integrity evaluation and mitochondrial membrane potential were used a combination of fluorescent probes. Differences between means values obtained by analysis of variance were verified by Tukey test with 5% probability. There was no statistical difference between treatment groups in relation to volume, mass moviment, total motility, vigour, concentration, plasma and acrosomal membrane integrity (p > .05). Sperm morphology was different between treatment groups, the G1 (0 mg of selenium) had the highest percentage of major defects (11.11 ± 1.11a; p < .05). It was concluded that selenium decrease the percentage of sperm defects and did not directly influence on ram sperm volume, mass moviment, total motility, vigour, concentration and membrane integrity.  相似文献   
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The vascular changes associated with endometrial maturation in preparation for embryo implantation depend on numerous growth factors, known to regulate key angiogenic events. Primarily, the vascular endothelial growth factor (VEGF) family promotes vascular growth, whilst the angiopoietins maintain blood vessel integrity. The aim was to analyse protein levels of VEGFA ligand and receptors, Angiopoietin‐1 and 2 (ANG1/2) and endothelial cell receptor tyrosine kinase (TIE‐2) in the ovine endometrium in the follicular and luteal phases of the oestrus cycle and in response to ovarian steroids. VEGFA and its receptors were localized in both vascular cells and non‐vascular epithelium (glandular and luminal epithelium) and stroma cells. VEGFA and VEGFR2 proteins were elevated in vascular cells in follicular phase endometrium, compared to luteal phase, most significantly in response to oestradiol. VEGFR1 was expressed by epithelial cells and endothelial cells and was stimulated in response to oestradiol. In contrast, Ang‐1 and Ang‐2 proteins were elevated in luteal phase endometrium compared to follicular phase, and in response to progesterone, evident in vascular smooth muscle cells and glands which surround TIE‐2‐expressing blood vessels. Our findings indicate that VEGFA is stimulated by oestradiol, most predominantly in follicular phase endometrium, and Ang‐1 and 2 are stimulated by progesterone and were increased during the luteal phase of the oestrus cycle, during the time of vascular maturation.  相似文献   
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We have investigated the reproductive development of the tropically adapted Santa Inês ram, the most common hair sheep in Brazil. From 8 to 48 weeks of age, 16 animals were evaluated for body and testis growth, semen parameters, testosterone concentrations and seminal plasma proteins, using two‐dimensional SDS‐PAGE. Animals were weaned at 30 days and kept in feedlots thereafter, receiving hay, concentrate (18% of crude protein) and mineral supplement. Body weight increased from 12.3 ± 0.7 to 54.3 ± 1.6 kg between 8 and 48 weeks (p < 0.05), but changes in thoracic perimeter and scrotal circumference were non‐significant after 36 weeks (p > 0.05). The percentage of motile sperm increased slowly until 23 weeks and more rapidly after that age, but significant changes in progressive motility occurred after 25 weeks. Presence of abnormal sperm related inversely to age. Most significant changes in sperm concentration occurred between 38 and 44 weeks (0.38 ± 0.05 to 1.14 ± 0.24 × 109 cells/ml, p < 0.05) and testosterone reached its highest concentrations at 42 weeks, decreasing afterwards. Rams reached puberty at 28.2 ± 0.8 weeks. The number of protein spots on seminal plasma gels was similar from 15 to 18 weeks (45 and 47 spots; p > 0.05), increased until 24 weeks (141 spots) and 28 weeks (170 spots; p < 0.05) and remained without significant (p > 0.05) changes from 28 to 48 weeks (186 ± 10 spots). Furthermore, the intensity of selected spots on 2D maps increased (p < 0.05) between 15 and 28 weeks, which preceded or coincided with the main developmental changes in sperm motility and percentage of defective sperm in the ejaculates. These results will support future studies designed to characterize specific seminal plasma proteins whose expression relate to the development of testis, epididymis and accessory sex glands.  相似文献   
66.
The aim of this study was to isolate Toxoplasma gondii and determine the viability of the parasite in fresh semen samples of clinically healthy adult dogs naturally infected. Eleven seropositive dogs with T. gondii IgG antibodies from southern Brazil were selected to confirm the presence and viability of T. gondii in fresh semen samples using in vitro isolation in Vero cell culture, polymerase chain reaction (PCR) and sequencing analysis. The presence of viable T. gondii was confirmed by in vitro isolation and PCR in five semen samples. The ITS1 region of the isolated protozoa (TG S4) was amplified and sequenced. The nucleotide sequence obtained was 99% compatible with the T. gondii DNA sequences stored in the GenBank. It has been shown that T. gondii tachyzoites may be isolated in vitro from fresh semen samples of clinically healthy dogs seropositive for T. gondii.  相似文献   
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The copper and zinc concentrations in the blood of stabled thoroughbred horses and in Australian Stock Horses mares at pasture, either late pregnant or lactating were determined by an atomic absorption spectroscopic method. The plasma concentration of the trace elements in these apparently normal horses were generally below the "normal" range. The plasma copper, caeruloplasmin copper, whole blood copper and plasma zinc concentrations in the stabled thoroughbreds were 0.76 +/- 0.19 micrograms/ml (n = 82), 0.56 +/- 0.14 micrograms/ml (n = 83), 0.75 +/- 0.18 micrograms/ml (n = 82) and 0.47 +/- 0.09 micrograms/ml (n = 83) respectively. The plasma copper and zinc concentrations of all the brood mares at pasture (pregnant and lactating) were 0.56 +/- 0.20 micrograms/ml and 0.47 +/- 0.11 micrograms/ml (n = 30). The plasma copper concentration of the pregnant group of mares (0.64 +/- 0.18 micrograms/ml; (n = 14) was greater than that of the lactating mares (0.49 +/- 0.21; (n = 16). Variation in the plasma copper concentration was also identified between stabled and farm horses, between horses of different stables and between horses of different ages. The proportion of plasma copper bound to caeruloplasmin was 73 +/- 11.8%. These low concentrations of copper and zinc in the plasma of apparently normal horses are of clinical significance since recent evidence has indicated that copper deficiency appears to promote the development of skeletal abnormalities in foals. An alternative to the use of a single plasma sample to identify the copper or zinc deficient horse was discussed.  相似文献   
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