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971.
Objective To compare plasma colloid osmotic pressure (COP) of both maternal and fetal blood, before and after hemorrhage, and replenishment with Oxyglobin Solution (Biopure Corporation, Cambridge, MA, USA), hetastarch or whole blood in pregnant ewes. Study design Prospective, randomized study. Animals A total of 17 adult Rambouillet ewes at 131 (128–133) [median (minimum, maximum)] days gestation, weighing 56 (46, 63) kg. Methods Ewes and fetuses were chronically instrumented with catheters in a maternal jugular vein, maternal carotid artery and fetal femoral artery. Twenty milliliters per kilograms of blood were removed from each ewe over 1 hour. The ewes were then given 20 mL kg?1 of either Oxyglobin Solution (n = 5), hetastarch (n = 6), or autologous whole blood (n = 6) IV. Maternal plasma COP was measured before hemorrhage, after hemorrhage, after replenishment, and 1 and 2 hours later. Fetal plasma COP was measured after maternal hemorrhage and 2 hours after maternal volume replenishment. Results Median COP of all ewes before hemorrhage was 20 (16, 24) mm Hg and after hemorrhage (p < 0.05), decreased to 16 (11, 19) mm Hg. After volume replenishment, the COP of the Oxyglobin Solution group was 22 (21, 25) mm Hg, the autologous whole blood group was 17 (16, 22) mm Hg and the hetastarch group was 20 (17, 21) mm Hg. The COP of the Oxyglobin Solution group was significantly greater (p < 0.05) than the COP of the hetastarch group immediately and 60 minutes after volume replenishment, and greater (p < 0.05) than that of the autologous whole blood group at 60 minutes after volume replenishment. The COP of all the fetuses after maternal hemorrhage was 16 (12, 19) mm Hg and at 120 minutes after maternal volume replenishment was 15 (11, 18) mm Hg. There were no differences in COP between or within any of the fetal groups. Conclusions When used to treat blood loss, Oxyglobin Solution increases plasma COP more than an equal volume of hetastarch in the first hour following administration. Maternal administration of Oxyglobin Solution did not alter fetal COP. Clinical relevance Oxyglobin Solution is a more potent colloid than hetastarch. Oxyglobin Solution did not appear to translocate fluid from the fetal to maternal circulation.  相似文献   
972.
With worldwide development of anthelmintic resistance, alternative approaches to the chemotherapeutic dominant approach for the control of parasitic nematodes in sheep are urgently required. As natural enemies of nematodes, nematophagous fungi offer the exciting possibility of an alternative to the dominant anthelmintic approach for parasite control in ruminants. Permanent sheep pasture harbor a promising array of nematophagous fungi and merits further investigation. One hundred and fifty samples of soil, old and fresh faeces were collected from 10 Irish sheep pastures. The three methods employed for the isolation of nematophagous fungi include the Baermann technique, flotation method and the sprinkling–baiting technique. Twenty-nine nematophagous fungi were observed of which 12 were predacious and 17 were endoparasitic. The most prevalent fungi were Cystopage lateralis, Stylopage hadra, Drechmeria coniospora and Meristacrum asterosperum. Permanent sheep pasture is a good source of nematophagous fungi and hence may harbor potential biological control agents. Monacrosporium cionopaga, Duddingtonia flagrans, D. coniospora and Hirsutella rhoissilensis were detected in fresh faecal samples indicating they may have survived the gastrointestinal tract and therefore a viable option as a biological control agent.  相似文献   
973.
Active hepatitis E virus (HEV) infections in two Brazilian swine herds were investigated. In study 1, 26 piglets born to five anti-HEV positive sows were monitored from birth to post-partum week 22. Serum samples were screened for the detection of anti-HEV antibodies and a nested RT-PCR used to examine the HEV genome. Passive transfer of immunity was confirmed. At week 22, 23/26 (88.4%) of the piglets had seroconverted. Genome amplification was achieved in a feces pool from one holding pen and in one serum sample, both from 13-week-old animals. Histology was suggestive of a potential HEV infection. In the second study, 47 piglets born to six anti-HEV-positive sows were monitored after weaning. Seroconversion was determined in eight animals at 6-8 weeks of age. HEV RNA was detected in two pools from a holding pen for 12-16-week-old animals. Brazilian isolates were classified as genotype 3. This is the first molecular evidence of HEV infection in Brazilian pig herds.  相似文献   
974.
Objective  To evaluate the quality of brachial plexus blockade with 0.75% ropivacaine in domestic chickens.
Study design  Prospective experimental trial.
Animals  Six 30-week-old female chickens, weighing 4.5 ± 0.4 kg.
Methods  Six brachial plexus injections were performed after anesthetic induction with isoflurane. After achieving adequate muscle relaxation, the animals were positioned in dorsal recumbency and injected with ropivacaine (1 mL kg−1). The birds recovered and assessments of motor function and response to pinch were scored every 5 minutes for 180 minutes. The scores were from zero (no response) to three (greatest response). The scores over time were analyzed using a Wilcoxon nonparametric test with statistical significance accepted if p  ≤ 0.05.
Results  There was a significant difference ( p  < 0.05) from 15 to 130 minutes and 15 to 120 minutes for motor and sensory blocks, respectively. The onset of both blocks took 15 minutes and the effective periods of sensory and motor anesthesia were 105 and 115 minutes, respectively. Comparison between blocks at different times did not demonstrate significant differences ( p  > 0.05).
Conclusions and clinical relevance  No complications were observed after the technique. Brachial plexus blockade with 0.75% ropivacaine is a simple and effective technique for procedures on the thoracic limb of domestic chickens.  相似文献   
975.
A 15-y-old castrated male Maine Coon cat was evaluated for an ulcerated soft tissue mass on the right hindlimb that had been observed for 4 mo and had grown rapidly. A 3 × 3 cm soft, raised, amorphous, and ulcerated subcutaneous mass was observed on the lateral right metatarsus. In-house cytology via fine-needle aspiration was nondiagnostic. Incisional biopsy of the mass and further staging was declined, and amputation was elected. The amputated limb was submitted for histopathology, which revealed severe chronic nodular granulomatous dermatitis and multifocal granulomatous popliteal lymphadenitis with large numbers of intralesional fungal hyphae. Fungal PCR and sequencing on formalin-fixed, paraffin-embedded tissue identified Chalastospora gossypii. No adjunctive therapy was elected at the time. The patient has done well clinically 1 y post-operatively. C. gossypii is a rare microfungus found worldwide and is considered a minor pathogen of several plants. To our knowledge, infection by this fungus has not been reported previously in veterinary species. Features in our case are comparable to other mycotic infections. Nodular granulomatous mycotic dermatitis and cellulitis, although uncommon, should be a differential for soft tissue masses in veterinary species; C. gossypii is a novel isolate.  相似文献   
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