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991.
992.
Effects of the oviduct and wheat germ agglutinin on enzymatic digestion of porcine zona pellucidae 总被引:1,自引:0,他引:1
Seventy-two crossbred gilts were utilized to examine whether the oviduct rendered zona pellucidae resistant to protease digestion, whether the uterus reversed this resistance and whether such a uterine reversal was necessary for hatching. Oocytes were aspirated from follicles 22 to 28 h after onset of estrus (d 0); oviductal and uterine oocytes or embryos were collected on d 1 to 6. These oocytes and embryos were subjected to a solution containing .1% trypsin and .1% pronase (37 degrees C) for observation of zona pellucidae digestion. Zonae of oviductal oocytes were more (P less than .001) resistant to digestion than were follicular oocytes. Placement of follicular oocytes in oviducts for 30 min rendered zona pellucidae more (P less than .001) resistant to protease digestion than oocytes not exposed to oviductal secretions. Resistance of zona pellucidae to proteases, however, decreased (P less than .001) after entry into the uterus. Zonae of morulae retained in oviducts took longer (P less than .001) to digest than those recovered from the uterus. Blastocysts also were treated with wheat germ agglutinin (WGA; 50 micrograms/ml) for 40 min to determine whether artificial induction of zona resistance to enzymatic digestion affected the ability of embryos to hatch. Though WGA treatment delayed (P less than .001) enzymatic digestion of zona pellucidae, time from collection to hatching was not affected. This experiment indicated that the oviduct delayed enzymatic digestion of the zona pellucidae, whereas the uterus reversed this delay. The re-establishment of enzyme susceptibility after uterine entry, however, appeared to be unrelated to the subsequent ability of blastocysts to hatch. 相似文献
993.
994.
Indirect hemagglutination for Eperythrozoon suis detection in experimentally and spontaneously infected swine 总被引:5,自引:0,他引:5
G Baljer K Heinritzi L Wieler 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(6):417-423
Ten splenectomized and non-splenectomized pigs were experimentally infected with E. suis bearing red blood cells in order to determine the antibody response. All animals were monitored for antibody titer by indirect hemagglutination over a period of 80-290 days postinfection. Latent E. suis infection only yielded a detectable antibody titer in one pig. Acutely infected pigs had a titer ranging up to 1:640. Maximum antibody response lasted only 2 months and dropped below the level of detection of our assay within 2 to 3 months. At this time, the clinical symptoms could reappear and antibodies were again detectable. However, no booster effect was observed with this second outbreak. We also determined the antibody frequency in 138 pigs from 16 herds in Southern Germany. Pigs from only 4 out of 6 clinically positive herds had antibody titer against E. suis. 20 out of 78 pigs of the clinical positive herds demonstrated a detectable E. suis antibody titer. In 10 herds that were asymptomatic and presumed uninfected all 80 pigs were serologically negative for E. suis. 相似文献
995.
Michail N. Patsikas DVM PhD Timoleon Rallis DVM PhD Stefanos E. Kladakis DVM Aggelos K. Dessiris DVM PhD 《Veterinary radiology & ultrasound》2001,42(3):235-237
Isolated splenic torsion in a dog was diagnosed using computed tomography (CT). The enlarged non enhanced spleen and a twisted soft tissue mass effect represented the rotated pedicle were the main findings. Abdominal radiography and ultrasonography were not conclusive. 相似文献
996.
R M Dabareiner J P Watkins G K Carter C M Honnas T Eastman 《Journal of the American Veterinary Medical Association》2001,219(1):82-86
OBJECTIVE: To determine clinical, radiographic, and scintigraphic abnormalities in and outcome of horses with septic or nonseptic osteitis of the axial border of the proximal sesamoid bones. DESIGN: Retrospective study. ANIMALS: 8 horses. PROCEDURE: Data collected from medical records included signalment; history; horse use; severity and duration of lameness; results of perineural anesthesia, radiography, ultrasonography, and scintigraphy; and outcome following surgery. RESULTS: Five horses did not have any evidence of sepsis; the other 3 had sepsis of the metacarpophalangeal or metatarsophalangeal joint or the digital synovial sheath. All horses had a history of chronic unilateral lameness. Three of 5 horses improved after diagnostic anesthesia of the metacarpophalangeal or metatarsophalangeal joint; the other 2 improved only after diagnostic anesthesia of the digital synovial sheath. Nuclear scintigraphy was beneficial in localizing the source of the lameness to the proximal sesamoid bones in 4 horses. Arthroscopy of the palmar or plantar pouch of the joint or of the digital synovial sheath revealed intersesamoidean ligament damage and osteomalacia of the axial border of the proximal sesamoid bones in all horses. All 5 horses without sepsis and 1 horse with sepsis returned to their previous uses. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that osteitis of the axial border of the proximal sesamoid bones is a distinct entity in horses that typically is associated with inflammation of the associated metacarpointersesamoidean or metatarsointersesamoidean ligament and may be a result of sepsis or nonseptic inflammation. Arthroscopic debridement may allow horses without evidence of sepsis to return to their previous level of performance. 相似文献
997.
Advanced reproductive techniques in goats. 总被引:2,自引:0,他引:2
K N Bretzlaff J E Romano 《Veterinary Clinics of North America: Food Animal Practice》2001,17(2):421-34, viii
The use of ultrasonography for pregnancy diagnosis and reproductive tract evaluation in the goat has become more common in the past decade. Pregnancy-specific hormone assays are commercially available for pregnancy determination in goats. Hormonal methods of synchronization of estrus for artificial insemination have been refined, but a number of factors still make pregnancy results variable. Caprine embryo transfer is widely used commercially. More advanced reproductive techniques such as in-vitro production of embryos and cloning have been accomplished in goats; success rates with these techniques will likely rapidly improve. 相似文献
998.
Seidler T Alter T Krüger M Fehlhaber K 《Berliner und Münchener tier?rztliche Wochenschrift》2001,114(9-10):375-377
On transport and at the abattoir animals are confronted with a lot of stressors, such as sound/noise, crowding/mixing, pollutants and infectious agents that act on the organism. After transport stress an endogenous contamination is often seen in slaughter carcasses and presents a hazard for the consumer. These events are often correlated with a rise in endotoxin level (Misawa et al., 1995; Morales et al., 1992) and a modified immune response. Previous own investigations confirm this hypothesis (Zucker and Krüger, 1998, Seidler et al., 2000). The attempt was made to investigate the impact of selected stressors (short term transport (1 h), long term transport (7-8 hrs), high temperature, high humidity and intense handling/moving) on bacterial translocation, endogenous contamination, endotoxin levels and bactericidal activity of body fluids. 相似文献
999.
1000.
Naganobu K Hagio M Sonoda T Kagawa K Mammoto T 《American journal of veterinary research》2001,62(1):127-129
OBJECTIVE: To determine effects of hypercapnia on arrhythmias in ducks anesthetized with halothane. ANIMALS: 12 ducks, 6 to 8 months old, weighing 1.1 to 1.6 kg. PROCEDURES: Each duck was anesthetized with a 1.5% mixture of halothane in oxygen, and anesthetic depth was stabilized during a 20-minute period. We added CO2 to the inspired oxygen to produce CO2 partial pressures of 40, 60, and 80 mm Hg in the inspired gas mixture.The CO2 partial pressure was increased in a stepwise manner. When arrhythmias were not evident during inhalation of the gas mixture at a specific CO2 partial pressure, the CO2 partial pressure was maintained for 10 minutes before a sample was collected for blood gas analysis. When arrhythmias were detected, a sample for blood gas analysis was collected after the CO2 partial pressure was maintained for at least 2 minutes, and CO2 inhalation then was terminated. RESULTS: During the stabilization period, PaCO2 (mean +/- SD) was 33 +/- 5 mm Hg,and arrhythmias were not detected. In 6 ducks, arrhythmias such as unifocal and multifocal premature ventricular contractions developed during inhalation of CO2. Mean PaCO2 at which arrhythmias developed was 67 +/- 12 mm Hg. In 5 of 6 ducks with arrhythmias, the arrhythmias disappeared after CO2 inhalation was terminated. CONCLUSION AND CLINICAL RELEVANCE: Analysis of data from this study indicated that hypercapnia can lead to arrhythmias in ducks during halothane-induced anesthesia. Thus, ventilatory support to maintain normocapnia is important for managing ducks anesthetized with halothane. 相似文献