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91.
Absorption of cysticerci in cattle after treatment of taenia saginata cysticercosis with praziquantel 总被引:1,自引:0,他引:1
Two groups of calves aged 10 to 15 weeks were orally infected with either 6000 or 30,000 Taenia saginata eggs. Three to four months later they were treated with praziquantel, three doses of 50 mg kg-1 on three consecutive days. All the cysticerci were killed by the drug and most were absorbed by between six and nine months after treatment. From then on there was little further absorption and residual calcified cysts were still found in the carcases up to 24 months after drug treatment. These residual calcified cysts were particularly common in the heart muscles and would probably have been detected at meat inspection. 相似文献
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93.
1. Conventional or gnotobiotic chicks, when injected from 1 d to 3 weeks of age with adrenocorticotrophic hormone (120IU/kg, three times weekly), showed a depressed growth rate, adrenal hypertrophy and depletion of cholesterol form the adrenal glands. 2. Feeding a diet supplemented with aureomycin (10 mg/kg) did not have any consistent ameliorating effect on the response of the stressed bird as judged by the above parameters. 3. It was found that treating germfree chicks with five daily injections of sterile milk on days 3 to 7 did not depress growth rate at any time, nor could differences in adrenal size or cholesterol stores be detected at the end of the 21-d experimental period. The responses were not modified by feeding an aureomycin-supplemented diet. 相似文献
94.
Peripheral alpha- and beta-adrenergic control of uterine blood flow (UBF) during acute heat stress of the gravid ewe was investigated. An electromagnetic blood flow probe was surgically implanted around the left miduterine artery and catheters inserted in the left carotid artery and right jugular vein in ewes between d 120 and 130 of gestation. Four or more days postsurgery, ewes were fitted with instruments to measure rectal temperature (Tr), heart rate (HR), respiratory rate (RR), blood pressure (BP) and UBF. One-half hour after instrument calibration, a 15-min thermoneutral control period was initiated with carotid artery blood samples taken at 5-min intervals for pH and PCO2 determinations. Ewes were then subjected to a heat challenge that reached 40 C at 2 h. All physiological data were recorded every 5 min as 1-min mean values. In seven experiments on five ewes, an alpha-adrenergic blocking drug, phenoxybenzamine (PB) was infused at 1 mg/min for 15 min subsequent to maximum depression of UBF. A beta-adrenergic blocking drug, propranolol (PR) was infused at .35 mg/min for 15 min in eight experiments on five ewes. Analysis of variance comparisons were made between the control period and heat stress infusion periods within the PB and PR experiments. Further comparisons were made between the start and 5, 10 or 15 min of PB or PR infusion in order to test drug effects during an acute heat stress. Rectal temperature HR, RR and arterial pH were higher (P less than .05) at the start of PR and PB infusions than during the thermoneutral control period.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
95.
Harrison TM Stanley BJ Sikarskie JG Bohart G Ames NK Tomlian J Marquardt M Marcum A Kiupel M Sledge D Agnew D 《Journal of zoo and wildlife medicine》2011,42(2):317-321
A 14-yr-old female eastern black rhinoceros (Diceros bicornis michaeli) presented with progressive suppurative osteomyelitis in her left hind lateral toe. beta-Hemolytic Streptococcus sp. was isolated. The animal was treated with multiple systemic antibiotics, and topical wound cleansing. Repeated debridements and nail trimmings were performed for 5 mo prior to electing amputation. The toe was surgically amputated under general anesthesia between the first and second phalanges. Analgesia was diffused into the wound topically via a catheter and elastomeric pump. The open amputation site was covered with adherent drapes and a negative-pressure wound therapy device provided vacuum-assisted closure (V.A.C.) for 72 hr. Three months later this animal developed a deep dermal ulcer on the lateral aspect of the right hind limb, at the level of the stifle. Methicillin-resistant Staphylococcus aureus was isolated. The wound was managed by initial daily lavage, followed by 1 mo of V.A.C. therapy, with 72 hr between dressing changes. Clinically, this therapy expedited the formation of healthy granulation tissue and overall healing was accelerated. The animal tolerated the machine and bandage changes well via operant conditioning. The use of negative-pressure wound therapy appeared to shorten time to resolution of slow-healing wounds in black rhinoceros. 相似文献
96.
Tara M Harrison Richard R Dubielzig Timothy R Harrison Modesto McClean 《Journal of zoo and wildlife medicine》2006,37(4):545-548
A 4-yr-old male guanaco (Lama guanicoe) in a multispecies exhibit presented with a laceration in the axillary region. The laceration was surgically repaired. Medical treatment was initiated with penicillin G procaine and benzathine (1920 IU/kg, i.m., s.i.d. for 14 days), and enrofloxacin (2.4 mg/kg, i.m., s.i.d. for 14 days). The animal was later treated with trimethoprim-sulfadiazine (24 mg/kg, p.o., s.i.d. for 10 days). Twenty-six days after initial presentation, the guanaco was suspected to be blind. An ophthalmic examination confirmed retinal damage. On postmortem histological evaluation, there was outer retinal atrophy that was most severe in the central retina with localized foci of complete retinal atrophy; lesions were similar to those observed in enrofloxacin retinal toxicity in cats. 相似文献
97.
98.
Tara M Harrison Jamee Black Moorman Steven R Bolin Nicole L Grosjean Ailam Lim Scott D Fitzgerald 《Journal of veterinary diagnostic investigation》2007,19(2):191-194
An adult female crested porcupine (Hystrix cristata) was evaluated for acute onset of neurologic signs including head tilt, circling, and ataxia. She was found dead in her holding area 2 days after initially exhibiting clinical signs. Necropsy was unremarkable. Histopathology of brain tissue revealed the presence of protozoal cysts associated with inflammation as the underlying cause of clinical signs and death. Immunohistochemical staining of brain tissue for Toxoplasma gondii was strongly positive. PCR on fresh brain confirmed T. gondii as the causative organism. An adult male in the same enclosure has demonstrated similar neurologic signs over the past 3 years and has failed to respond to various medical treatments. Clinical disease associated with T. gondii has not been previously reported in this porcupine species or any other Old World porcupines, although there are several reports of clinical toxoplasmosis involving New World porcupine species. 相似文献
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100.