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991.
Diagnostic evaluation of, and treatment planning for, different periodontal diseases of dogs are a common problem in veterinary dentistry. Therefore the aim of the present study was to propose a classification for inflammatory periodontal disease. One hundred and twenty-three male and female poodles (from two to over 12 years) were used for the clinical investigations; 120 periodontitis teeth were analysed for pathomorphological signs of inflammation. The recorded data made it possible to differentiate five forms of gingivitis (gingivitis simplex, hyperplastica, ulcerosa, granulomatosa and desquamativa) and three forms of periodontitis (juvenile, rapidly progressive adult and chronic adult periodontitis). The pathomorphological investigations allowed a differentiation between acute progressive inflammation, chronic nonprogressive inflammation, chronic proliferative inflammation and chronic resorptive inflammation. It is concluded that standardised diagnoses as well as the pathomorphological background may be helpful tools for providing effective treatment strategies.  相似文献   
992.
Rabbit haemorrhagic disease virus (RHDV) was illegally released in New Zealand in August 1997. The initial release and spread of the virus was conducted by landholders in an effort to reduce costs associated with more conventional control methods (poisoning and shooting). Serum was collected from wild rabbits throughout the Otago region prior to the release and from 13 sites in the months following the first epizootic. Following the occurrence of the first RHDV epizootic on 13 pastoral farming properties a range of survival rates was found. The major factor influencing the survival rate was found to be the method of release, with widespread use of carrot or oat baits containing RHDV resulting in poor kills. Widespread use of baits also resulted in higher levels of antibody in surviving adult rabbits with a higher proportion of adult females surviving the epizootic, compared with properties where the disease was allowed to spread naturally. A correlation was found between survival rate and the percentage of surviving adults with high levels of antibody. These results suggest that poor kill rates are not due to poor spread of the virus, that the large-scale use of baits resulted in protective immunisation and that rabbit control should in the future be achieved through establishing naturally spreading epidemics rather than widespread use of baits.  相似文献   
993.
994.
Information provided by wool growers in Queensland, Australia between 1995 and 1997 was used to assess the prevalence and spatial distribution of louse (Bovicola ovis) infestation in sheep flocks. The estimated prevalence of louse-infested flocks was 40% (95% confidence interval, 35-46%). Although the prevalence of infestation was higher in western regions (41-50%) compared to the south region of Queensland (31%), the difference was not statistically significant (P > 0.05). Significant (P = 0.02) clustering of infested flocks was detected in the south region where two foci were apparent. We conclude that Queensland sheep flocks have a moderate prevalence of louse infestation, and that clustering of infestation is not strong. The control of lice is an industry-wide issue that needs to be addressed by most wool growers in Queensland.  相似文献   
995.
A study was undertaken to compare Tifton 85 (T85) and Coastal (CBG) bermudagrasses for effects of cultivar and age at harvest on yields of DM and digestible DM, in vitro digestion, nutrient content, cell wall composition, in situ digestion kinetics, and feed intake and digestion by growing beef steers. In Exp. 1, T85 and CBG forages staged for growth in May or July of 1993 were harvested at 3, 4, 5, 6, 7, and 8 wk from subplots. Tifton 85 bermudagrass had 7.1% greater DM yield, 18.2% higher (P < .05) digestible DM yield, and 7.1% greater IVDMD than CBG, and, after 5 wk of forage growth, IVDMD of both T85 and CBG decreased with increased age at harvest (P < .05). In Exp. 2, T85 and CBG forages staged for growth in July 1997 were harvested at 2, 3, 4, 5, 6, and 7 wk from subplots. Even though T85 had higher concentrations of NDF and ADF than CBG, T85 had 34.1% higher DM yield, 47.9% higher digestible DM, 55.0% higher digestible NDF, 91.7% higher digestible ADF, greater IVDMD, in vitro NDF and ADF disappearances, and higher in situ DM and NDF digestion (P < .05). Coastal bermudagrass had higher concentrations of lignin and lower concentrations of total neutral sugars, arabinose, glucose, and xylose than T85 (P < .05). In vitro digestibilities of DM, NDF, and ADF were lower and concentrations of ADF and lignin were greater for 7- vs 6-wk harvests of both T85 and CBG (P < .05). In Exp. 3, T85 and CBG forages staged for growth in July 1997 were harvested as hay at 3, 5, and 7 wk from .8-ha pastures and fed to 36 individually penned growing beef steers (initial BW = 244 kg) to quantify ad libitum intake without supplementation. Tifton 85 bermudagrass had lower concentrations of lignin and ether-linked ferulic acid and greater concentrations of NDF, ADF, hemicellulose, and cellulose than CBG (P < .05). Steers fed T85 had higher (P < .05) digestion of DM, OM, NDF, ADF, hemicellulose, and cellulose than steers fed CBG. Digestion of NDF, ADF, hemicellulose, and cellulose decreased (P < .05) with increased age at harvest for both cultivars. In conclusion, T85 produced more DM and had more digestible nutrients in vitro, in situ, and in vivo than CBG, and 3 and 5 wk of growth would be recommended ages to harvest either cultivar.  相似文献   
996.
Long limb bones were dissected from 30 Camborough x Canabrid pigs serially slaughtered at birth, 14, 28, 56, and 84 d of age to determine the growth patterns of long limb bones (humerus and radius for the forelimb and femur and tibia for the hindlimb) in relation to live weight from birth to 84 d of age, weighing up to approximately 31 kg. Relationships between individual long limb bone measurements (Y) and live weight or transformations of live weight (X) were evaluated using allometric analyses. Hindlimb bones tended to have higher growth coefficients than forelimb bones (P < .05), suggesting an anterior-posterior gradient of long limb bone growth. However, centripetal gradients of growth for long limb bones were not evidential (P > .05). Greater diameter growth compared with length growth of the long limb bones indicated that the differentiation in growth for diameter and length of the long limb bones was an effective response to the functional requirements of standing, walking, and running following birth.  相似文献   
997.
Ergocryptine is an ergot alkaloid that affects dopaminergic activity principally by interacting with D2-type receptors. In this study the ability of ergocryptine and several other ergot alkaloids to release [3H]dopamine from isolated nerve endings was demonstrated using in vitro superfusion of rat striatal synaptosomes. Ergocryptine, ergocristine, and bromocryptine produced an elevation in baseline dopamine release of approximately 400% with effective concentrations (EC50) of approximately 30 microM. Ergotamine, ergonovine, ergovaline, and ergocornine were devoid of activity. The time-course of the ergocryptine-stimulated release was relatively slow compared with amphetamine, nicotine, or K+-stimulated [3H]dopamine release; the maximal increase in release required a 5-min treatment. A number of receptor antagonists were examined for their ability to block ergocryptine-stimulated release. Of the dopaminergic, adrenergic, serotonergic, GABA-ergic, and cholinergic antagonists examined, only phentolamine produced a moderate attenuation in evoked release. Omission of Ca++ from the medium did not affect ergocryptine-evoked release. Following ergocryptine treatment, the synaptosomes were fully responsive to other stimulant. The results indicate that, in addition to interacting with dopamine receptors, several ergot alkaloids may produce dopaminergic effects by increasing the release of dopamine from central nerve endings. Several mechanisms to account for the evoked neurotransmitter release are discussed.  相似文献   
998.
Appraisal of the indirect fluorescent antibody test (IFAT) and antigen enzyme linked immunosorbent assay (ELISA) serological tests as carried out to detect cattle exposed to Theileria parva at the National Veterinary Research Centre, Muguga (NVRC), Kenya is reported. Using sera from T. parva naive cattle and cattle experimentally exposed to T. parva, the two tests were appraised in terms of their sensitivity and specificity. IFAT and ELISA had the same sensitivity of 90% while ELISA had a higher specificity (90%) than IFAT (80%). A comparison was also made of the capability of the two tests to detect exposure of dairy cattle to T. parva prior to immunization against East Coast fever (ECF). The positive outcome from the IFAT was significantly higher (chi 2 = 30.36; P < 0.001) than that from the ELISA. The agreement between the two tests was low (Kappa = 0.21). The two tests indicated a higher risk of ECF in the study area than was expected. Indications are that the ELISA has been effectively adopted at NVRC.  相似文献   
999.
An improved ability to quantify differences in the fabrication yields of beef carcasses would facilitate the application of value-based marketing. This study was conducted to evaluate the ability of the Dual-Component Australian VIASCAN to 1) predict fabricated beef subprimal yields as a percentage of carcass weight at each of three fat-trim levels and 2) augment USDA yield grading, thereby improving accuracy of grade placement. Steer and heifer carcasses (n = 240) were evaluated using VIASCAN, as well as by USDA expert and online graders, before fabrication of carcasses to each of three fat-trim levels. Expert yield grade (YG), online YG, VIASCAN estimates, and VIASCAN estimated ribeye area used to augment actual and expert grader estimates of the remaining YG factors (adjusted fat thickness, percentage of kidney-pelvic-heart fat, and hot carcass weight), respectively, 1) accounted for 51, 37, 46, and 55% of the variation in fabricated yields of commodity-trimmed subprimals, 2) accounted for 74, 54, 66, and 75% of the variation in fabricated yields of closely trimmed subprimals, and 3) accounted for 74, 54, 71, and 75% of the variation in fabricated yields of very closely trimmed subprimals. The VIASCAN system predicted fabrication yields more accurately than current online yield grading and, when certain VIASCAN-measured traits were combined with some USDA yield grade factors in an augmentation system, the accuracy of cutability prediction was improved, at packing plant line speeds, to a level matching that of expert graders applying grades at a comfortable rate.  相似文献   
1000.
The role of the ixodid tick Hyalomma lusitanicum Koch 1844 as a vector of Mediterranean or tropical theileriosis (caused by the protozoan parasite Theileria annulata Dschunkowsky et Luhs 1904) in southern Spain was studied. Hyalomma lusitanicum was the most common tick, and the only species of the genus Hyalomma L., found on T. annulata-infected cattle from the theileriosis enzootic area studied (province of Cádiz, southern Spain). Likewise, we found that all sera of the cattle previously considered as suspected of theileriosis by clinical signs, tested for T. annulata antibodies, were positive and all blood samples of these suspected cattle examined had infected erythrocytes. Partially fed H. lusitanicum adults were collected in the field on T. annulata-infected cattle in this enzootic area and fed on an uninfected calf in an experimental farm free of theileriosis and ticks. At approximately 3 weeks post-tick feeding on the calf, this became positive for T. annulata antibodies and T. annulata merozoites were found in erythrocytes from blood smears. These results show the ability of H. lusitanicum to transmit the protozoan parasite T. annulata to susceptible cattle and indicate that H. lusitanicum is probably an important vector of T. annulata in the enzootic area surveyed.  相似文献   
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