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71.
A five-year-old German shepherd dog was presented with a severe scrotal dermatitis of four weeks duration which had failed to respond to antibiotic and corticosteroid therapy. Dermato-histopathology indicated that the lesion was a necrolytic process suggestive of the hepatocuta-neous syndrome. Clinical biochemistry investigations indicated the presence of acute hepatocellular damage and cholestasis. The animal was fed a biscuit meal which was damp and mouldy. Penicillium vindication was grown from this feedstuff and three mycotoxins, citrinin, ochratoxin A and sterigmatocystin, were found; substances which have been associated with renal and hepatic lesions in dogs and laboratory animals. Symptomatic therapy and nutritional management, led to rapid clinical improvement. Subsequent plasma biochemistry confirmed that hepatic enzyme activities were returning to normal levels.  相似文献   
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The morphology of complex deposits of Pleistocene sediments covering the upper continental slope between Lindenkohl Canyon and South Toms Canyon results from both depositional and erosional processes. Small slump or slide features were detected primarily on the flanks of canyons or valleys and were observed to occur only within Pleistocene-aged sediments. Eocene to Miocene sediments are exposed over much of the mid- and lower slope in this area.  相似文献   
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Seven well-controlled studies conducted under multiple management conditions demonstrated that ceftiofur, a late-generation veterinary parenteral cephalosporin, is effective for the treatment of bovine foot rot in beef and dairy cattle. Two preliminary dosage titration studies using a challenge model compared the efficacy of ceftiofur (1.1 mg or 2.2 mg ceftiofur equivalents [CE]/kg administered once daily for 3 days) with placebo. One preliminary clinical study evaluated the efficacy of ceftiofur sodium (1.0 mg CE/kg once daily for 3 days) in lactating dairy cows. Two clinical trials evaluated the efficacy of ceftiofur sodium versus placebo for naturally occurring foot rot, and two trials compared the efficacy of ceftiofur sodium or hydrochloride (1.0 mg CE/kg) with oxytetracycline (6.6 or 10 mg/kg), each administered once daily for 3 days, for treatment of acute foot rot in beef cattle. All trials demonstrated the efficacy of ceftiofur for treatment of acute bovine foot rot. Ceftiofur and oxytetracycline were comparable in efficacy, with ceftiofur having excellent injection-site tolerance and short or no milk discard or preslaughter withdrawal.  相似文献   
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This study determined whether the interval from estrus to ovulation was altered by giving P.G. 600 to sows at weaning. Mixed-parity sows received P.G. 600 i.m. (n = 72) or no treatment (n = 65) at weaning (d 0). Beginning on d 0, sows were observed for estrus twice daily. At the onset of estrus and thereafter, ultrasound was performed twice daily to determine the average size of the largest follicles and time of ovulation. Weaning age (20.1+/-0.4 d) did not differ (P > 0.10) between treatments. More P.G. 600 sows expressed estrus within 8 d (P < 0.01) than controls (94.4% vs 78.4%, respectively). Parity was associated with expression of estrus (P < 0.02), with 78% of first-parity and 93% of later-parity sows exhibiting estrus. However, no treatment x parity effect was observed (P > 0.10). The interval from weaning to estrus was reduced (P < 0.0001) by P.G. 600 compared with controls (3.8+/-0.1 d vs 4.9+/-0.1 d). Follicle size at estrus was not affected by treatment (P > 0.10). The percentage of sows that ovulated did not differ (P > 0.10) for P.G. 600 and control sows (90.3% vs 81.5%, respectively). Time of ovulation after estrus was not affected by treatment and averaged 44.8 h. However, univariate analysis indicated that the interval from weaning to estrus influenced the interval from estrus to ovulation (r = 0.43, P < 0.0001). Further, multivariate analysis showed an effect of treatment on the intervals from weaning to estrus, weaning to ovulation (P < 0.0001), and estrus to ovulation (P < 0.04). Within 4 d after weaning, 81% of the P.G. 600 sows had expressed estrus compared with 33% of controls. However, this trend reversed for ovulation, with only 35% of P.G. 600 sows ovulating by 36 h after estrus compared with 40% of controls. The estrus-to-ovulation interval was also longer for control and P.G. 600 sows expressing estrus < or = 3 d of weaning (45 h and 58 h, respectively) than for sows expressing estrus after 5 d (39 h and 32 h, respectively). Farrowing rate and litter size were not influenced by treatment. However, the interval from last insemination to ovulation (P < 0.02) indicated that more sows farrowed (80%) when the last insemination occurred at < or = 23 to > or = 0 h before ovulation compared with insemination > or = 24 h before ovulation (55%). In summary, P.G. 600 enhanced the expression of estrus and ovulation in weaned sows but, breeding protocols may need to be optimized for time of ovulation based on the interval from weaning to estrus.  相似文献   
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Cattle and sheep, grazed successively on the same pasture and given the same supplementary feeding, developed ataxia and several animals became recumbent. Three cattle died within two weeks and the worst affected sheep were killed for laboratory examination. The supplementary diet which consisted largely of a distillery by-product, malt culms, was submitted for mycological examination and fed to two housed lambs. Aspergillus clavatus was cultured from the culms, and both the affected sheep and the housed lambs showed cerebrospinal degenerative changes. The clinical signs and neuropathology were closely similar to a mycotoxicosis, attributed to A clavatus, which is seen infrequently in cattle in France, Bulgaria, South Africa and China.  相似文献   
79.
Ceftiofur sodium, a broad-spectrum cephalosporin, is active against gram-positive and gram-negative pathogens of veterinary importance. This study was designed to compare the bioequivalence of the sodium salt in cattle after a single intramuscular (i.m.) or subcutaneous dose (s.c.) of 2.2 mg ceftiofur equivalents/kg body weight. The criteria used to evaluate bioequivalence were (1) the area under the curve from time of injection to the limit of quantitation (LOQ) of the assay (AUC0-LOQ), and (2) time concentrations remained above 0.2 microg/mL (t>0.2). Twelve crossbred beef cattle were enrolled in a three-period, two-treatment crossover trial, with a minimum 2-week washout period between doses of 2.2 mg ceftiofur equivalents/kg. Blood samples were collected serially for up to 72 h post-injection. Plasma samples were then analyzed using a validated assay that measures ceftiofur, and all desfuroylceftiofur-related metabolites, by high-performance liquid chromatography (HPLC) as the stable derivative, desfuroylceftiofur acetamide. A maximum plasma concentration (Cmax) of 13.9+/-3.55 microg/mL was observed from 0. 67-2.0 h after i.m. administration, whereas a Cmax of 13.6+/-3.85 microg/mL was observed from 0.67-3.0 h after s.c. administration. The AUC0-LOQ was 108+/-35.0 microg. h/mL after i.m. dosing, compared with 105+/-29.8 microg. h/mL after s.c. dosing. The pre-established criterion for equivalence of the AUC0-LOQ for the i.m. and s.c. routes of administration was satisfied. The t>0.2 was 49.2+/-8.55 h after i.m. administration, compared with 47.0+/-9.40 h after s.c. administration. The pre-established criterion for equivalence of the t>0.2 for i.m. and s.c. administration was satisfied. The equivalence of AUC0-LOQ and t>0.2 for i.m. and s.c. administration of 2.2 mg ceftiofur equivalents (CE)/kg doses of ceftiofur sodium suggest similar therapeutic efficacy and systemic safety for the two routes of administration.  相似文献   
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