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911.
Vivo J Morales JL Díz A Galisteo AM Monterde JG Agüera E Miró F 《Anatomia, histologia, embryologia》2006,35(3):184-189
The right intracranial portion of the oculomotor, trochlear and abducent nerves were removed from six adult German shepherd dogs and analysed by light and electron microscopy. In all cases the nerve sectional area was calculated. Unmyelinated and myelinated fibres were analysed and number, diameter and cross-sectional area were calculated. In myelinated fibres, also calculated were the corresponding axon area and diameter, and myelin sheath thickness. The mean number of myelinated fibres was 8543.50 +/- 1231.85 being the unmyelinated 1402 +/- 241.58 in the oculomotor nerve; 1509 +/- 223.17 and 287.67 +/- 72.28 in the trochlear nerve and 2473.00 +/- 211.41 and 231.25 +/- 92.67 respectively in the abducent. The mean diameter was 10.23 +/- 0.68 microm in myelinated and 0.43 +/- 0.21 for unmyelinated in oculomotor nerve, 10.53 +/- 0.55 microm and 0.33 +/- 0.04 for the trochlear, and 10.45 +/- 1.27 microm and 0.47 +/- 0.09 in the abducent nerve respectively. This study reveals that oculomotor, trochlear and abducent nerves of the dog show structural and ultra-structural features similar to the same nerves in other species. 相似文献
912.
Heather E Clarke Helen Kado-Fong David J Maggs 《Journal of veterinary diagnostic investigation》2006,18(4):388-391
The purpose of this study was to report methods currently recommended by commercial laboratories for collecting, shipping, and processing of samples for feline herpesvirus type 1 (FHV-1) testing using polymerase chain reaction (PCR) and to determine the effect of temperature and time on the ability of 1 PCR method to detect FHV-1 DNA in experimental and clinical samples. Eleven laboratories offering FHV-1 PCR were surveyed. There was notable variation in sample types and shipping conditions recommended and PCR protocols used by these laboratories. Subsequently, using a single PCR method, FHV-1 DNA was detected in samples exposed to various temperatures within the laboratory. Finally, FHV-1 PCR was performed on paired clinical samples collected from 25 cats and shipped at ambient temperatures via US Postal Service (USPS) or with an ice pack via a courier. Samples sent by USPS were exposed to significantly longer transit time and arrived at significantly higher temperature than did samples sent by courier. Despite this, all sample pairs yielded concordant results when tested for FHV-1 DNA using this PCR method. Although it may not be necessary for samples collected for detection of FHV-1 DNA using this PCR method to be shipped under the most expedient or temperature-controlled conditions, this should be verified for a variety of PCR assays and sample types. 相似文献
913.
Fernández-Varón E Ayala I Marín P Carrión A Martos N Escudero E Cárceles CM 《Equine veterinary journal》2006,38(4):342-346
REASONS FOR PERFORMING STUDY: Danofloxacin is a fluoroquinolone developed for veterinary medicine showing an excellent activity. However, danofloxacin pharmacokinetics profile have not been studied in horses previously. OBJECTIVE: To study the pharmacokinetics following i.v., i.m. and intragastric (i.g.) administration of 1.25 mg/kg bwt danofloxacin to 6 healthy horses. METHODS: A cross-over design was used in 3 phases (2 x 2 x 2), with 2 washout periods of 15 days (n = 6). Danofloxacin (18%) was administered by i.v. and i.m. routes at single doses of 1.25 mg/kg bwt. For i.g. administration an oral solution was prepared and administered via nasogastric tube. Danofloxacin concentrations were determined by HPLC assay with fluorescence detection. Tolerability at the the site of i.m. injection was monitored by creatine kinase (CK) activity. RESULTS: Danofloxacin plasma concentration vs. time data after i.v. and i.g. administration could best be described by a 2-compartment open model. The disposition of i.m. administered danofloxacin was best described by a one-compartment model. The terminal half-lives for i.v., i.m. and i.g. routes were 6.31, 5.36 and 4.74 h, respectively. Clearance value after i.v. dosing was 0.34 l/kg bwt/h. After i.m. administration, absolute bioavailability was mean +/- s.d. 88.48 +/- 11.10% and Cmax was 0.35 +/- 0.05 mg/l. After i.g. administration, absolute bioavailability was 22.36 +/- 6.84% and Cmax 0.21 +/- 0.07 mg/l. CK activity following i.m. dosing increased 3-fold over pre-injection levels 12 h after dosing and subsequently approached (but did not reach) normal values at 72 h post dose. CONCLUSIONS: Systemic danofloxacin exposure achieved in horses following i.m. administration was consistent with the predicted blood levels needed for a positive therapeutic outcome for many equine infections. Conversely, danofloxacin utility by the i.g. route was limited by low bioavailability. Tolerability associated with i.m. administration was high. POTENTIAL RELEVANCE: Pharmacokinetics, blood levels and good tolerability of i.v. and i.m. administration of danofloxacin in horses indicates that it is likely to be effective for treating sensitive bacterial infections. 相似文献
914.
Steven C Zicker Karen J Wedekind Dennis E Jewell 《Veterinary Clinics of North America: Small Animal Practice》2006,36(6):1183-98, v
Nutritional antioxidants have experienced a surge in research and interest in the past 20 years. this surge may be attributed to the improved methodology for investigation as well as the focus on diseases and aging processes related to oxidative stress that lend themselves to opportunistic outcomes. As such, the field of veterinary nutritional antioxidant research is also beginning to yield some interesting results, albeit, small in number compared with laboratory animals and human beings. Nonetheless, this article updates the practitioner on recent advances in research involving nutritional antioxidant applications in companion animals. 相似文献
915.
Waghorn TS Leathwick DM Rhodes AP Lawrence KE Jackson R Pomroy WE West DM Moffat JR 《New Zealand veterinary journal》2006,54(6):271-277
AIM: To establish the prevalence of anthelmintic resistance in parasitic nematodes on sheep farms in New Zealand. METHODS: A cross-sectional prevalence study was conducted, using a standardised faecal nematode egg count (FEC) reduction (FECR) test (FECRT) for ivermectin, at a full (0.2 mg/kg) and half (0.1 mg/kg) dose rate, and albendazole, levamisole and albendazole-levamisole in combination, on 60 lambs (n=10 per group) on farms selected from throughout New Zealand. Farms that conformed with selection criteria were chosen at random (n=80) or with a history of suspected resistance to macrocyclic lactone (ML) anthelmintics (n=32). Resistance to an anthelmintic was inferred when there was <95% reduction in FEC 7-10 days after treatment. Larval cultures were performed for all control groups and for treated groups for which resistance was evident. RESULTS: Of the farms randomly selected, 36% showed > or =95% FECR for all anthelmintics tested; resistance to ivermectin at 0.1 and 0.2 mg/kg liveweight was evident on 36% and 25% of these farms, respectively. Resistance to both ivermectin (0.2 mg/kg) and levamisole was evident on 8/80 (10%) farms, to ivermectin and albendazole on 10/80 (13%) farms, and to ivermectin, levamisole and albendazole on 6/80 (8%) farms. The prevalence of resistance to a half dose of ivermectin tended to be more prevalent on farms with a history of suspected ML resistance (p=0.06). Resistance to albendazole was seen across all the main parasite genera, and to levamisole in Nematodirus, Ostertagia (= Teladorsagia) and Trichostrongylus species. Resistance to ivermectin was dominated by Ostertagia spp, although Cooperia, Nematodirus and Trichostrongylus species were also implicated. CONCLUSION: Anthelmintic resistance in parasitic nematodes of sheep is common in New Zealand. Not only was resistance to albendazole and levamisole common, but resistance to the ML, ivermectin, was at a higher prevalence than expected. Sheep farmers and advisors in New Zealand need to re-evaluate the way they manage parasites, and more research is urgently needed if the steady decline in anthelmintic susceptibility is to be halted. 相似文献
916.
Skoufos I Voidarou Ch Bezirtzoglou E Tzora A 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(10):499-501
In total, 308 paired-samples of teat duct material and milk, were collected before and 50-70 min after machine-milking, from 30 ewes. Samples were processed bacteriologically. For analysis of results, we compared changes in bacterial isolation following milking, for duct and milk samples; statistical significance was assessed by the Sign Test. Bacteria were isolated from 18 (6%) duct and 19 (6%) milk samples collected before the milking procedure; respective figures after it, were 81 (26%) and 33 (11%). In 77 (25%) cases, bacteriological findings in the two duct samples of each pair were different; in seven cases bacteria were isolated only before, whilst in 70 cases bacteria were isolated only after milking (P < 0.005); respective results for milk samples were 26 (8%): 6 and 20 cases (P = 0.693). The majority of bacterial isolates were staphylococci, accounting for 63% of 99 isolates. The milking procedure predisposes to entrance of bacteria into the teat duct; however, increased bacterial isolation from the teat did not result to increased mammary infections, likely as a consequence of defence mechanisms present in healthy teats. 相似文献
917.
The results of vaccinating two groups of puppies with commercial vaccines, both of which claimed to provide adequate protection with a final vaccination at 10 weeks of age, were compared. Groups of 19 and 20 puppies with similar titres of maternally derived antibodies against canine parvovirus (cpv), canine distemper virus (cdv) and canine adenovirus type 2 (cav-2) at four weeks of age were vaccinated at six and 10 weeks of age and their responses to each vaccination were measured by comparing the titres against cpv, cdv and cav-2 in the serum samples taken immediately before the vaccination and four weeks later. After the vaccination at six weeks of age, all 19 of the puppies in group 1 had responded to cpv and cdv, and 14 had responded to cav-2; in group 2, 17 of the 20 had responded to cpv, 19 to cdv and 15 to cav-2. In both groups the puppies that did not respond to the first vaccination had responded serologically to cpv, cdv and cav-2 at 10 weeks of age. 相似文献
918.
919.
del Castillo JR Laroute V Pommier P Zémirline C Keïta A Concordet D Toutain PL 《Journal of animal science》2006,84(11):3155-3166
Anorexigenic substances released during infection may hinder the therapeutic efficacy of in-feed antibiotics. Paracetamol (acetaminophen; PARA) inhibits the anorexia of infection and seems to improve the clinical efficacy of doxycycline (DOX) against bacterial respiratory disease in swine herds. In order to verify whether PARA selectively stimulates intake of DOX-medicated feed in diseased pigs, we documented the pharmacokinetics (PK) of DOX when coadministered with PARA and examined the effect of in-feed PARA on the interindividual variability in plasma concentrations after systemic exposure to in-feed DOX in swine herds with respiratory disease. Systemic exposure to DOX was measured with the area under the curve (AUC) of its plasma concentrations over time. First, a rich-sampling PK study of in-feed and i.v. DOX (10 mg/kg of BW) and PARA (30 and 10 mg/kg of BW, respectively) was performed on 5 pigs. The PK profiles of in-feed DOX were used in mathematical simulations to determine 5 optimal sampling times for the farm-based population PK study. A randomized, blind, parallel PK study was performed in 2 herds with bacterial respiratory disease, where liquid feed was fortified with DOX alone (5 mg x kg of BW(-1) x meal(-1)) or combined with PARA (15 mg x kg of BW(-1) x meal(-1)). Medicated meals were given twice, 12 h apart, to group-housed growing pigs (n > 50 pigs x treatment(-1) x herd(-1), totaling 215 pigs). Plasma concentrations of DOX and PARA were measured with HPLC. At variance with our expectations, PARA decreased (P = 0.069) mean AUC of in-feed DOX and did not decrease its variability (P > 0.34). Mean AUC of DOX increased with feed intake and with initial exposure to DOX, and was greater in sick animals. Therefore, symptomatic PARA-induced improvement in bacterial respiratory disease control with DOX is more likely caused by its analgesic/antipyretic effects than by its orexigenic effect. Interindividual variation in the AUC of DOX was large in pigs given group medication, even when sufficient feeding space was allowed and the amount of feed offered was greater than their requirements. Therefore, future studies to improve the efficacy of group antibiotic therapy should focus on feeding behavior characteristics as well as biopharmaceutical properties of medicated feeds. 相似文献
920.
The aim of this study was to develop sustained release plant extracts as a potential alternative to antibiotic growth promoters for growing pigs. Pellets with a core based on microcrystalline cellulose and 3 active compounds (eugenol, carvacrol, and thymol) were prepared using rotary fluidized-bed technology. Two particle sizes were produced that had a mean size of approximately 250 and 500 mum. Results show the process was able to produce pellets with a spherical and homogenous form when 10% of the active compounds were incorporated into the core. When active compounds were increased to 20%, the pellet became stickier, and the yield decreased from 90 to 65%. Different amounts of coating in the form of an aqueous-based ethylcellulose (EC) dispersion (Surelease) were applied to the core to modify the release of active compounds. The efficacy of the coating was evaluated in vitro using a flow-through cell apparatus. The time to achieve 50 and 90% dissolution increased with the increase in particle size (P < 0.05) and the increase in EC-coating level from 10 to 20% (wt/wt; P < 0.05), indicating the ability of the process to slow release depending on particle size and the amount of polymer applied. Differences in the release of the active compounds were observed in the same formulation of pellets, except for the formulation with small 10%-EC-coated particles, in which the active compounds were rapidly dissolved (more than 85% in 15 min or less). For all other formulations, the dissolution time for eugenol was always faster than for thymol or carvacrol. The close monitoring of plant extract behavior in the gastrointestinal tract could become a key factor in the continued use of phyto-molecules as alternatives to antibiotic growth promoters and in optimizing the balance between cost and efficacy. Different microencapsulation technologies can be used, of which the rotary fluidized bed warrants consideration because of the quality of the products obtained. 相似文献