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91.
Extract The microclimate of the fleece is important for a number of reasons. First, it may be considered as a buffer system between the animal and the macroclimate and, as such, has an important influence on the way the sheep manipulates its body temperature control mechanism. Secondly, it is an important component of the environment in which can be found large numbers of micro-organisms, some of which are harmful to the animal and some harmful to the fleece. Thirdly, it influences the survival and habits of a number of ectoparasites and these, too, can be harmful to the animal and the fleece. 相似文献
92.
Yabsley MJ McKibben J Macpherson CN Cattan PF Cherry NA Hegarty BC Breitschwerdt EB O'Connor T Chandrashekar R Paterson T Perea ML Ball G Friesen S Goedde J Henderson B Sylvester W 《Veterinary parasitology》2008,151(2-4):279-285
To identify the tick-borne pathogens in dogs from Grenada, we conducted a serologic survey for Ehrlichia canis in 2004 (104 dogs) and a comprehensive serologic and molecular survey for a variety of tick-borne pathogens in 2006 (73 dogs). In 2004 and 2006, 44 and 32 dogs (42.3% and 43.8%) were seropositive for E. canis, respectively. In 2006, several tick-borne pathogens were identified by serology and PCR. DNA of E. canis, Anaplasma platys, Babesia canis vogeli, Hepatozoon canis, and Bartonella sp. were identified in 18 (24.7%), 14 (19.2%), 5 (7%), 5 (7%), and 1 (1.4%) dogs, respectively. Six (8.2%) dogs were seropositive for Bartonella vinsonii subsp. berkhoffii. All dogs were seronegative and PCR-negative for Rickettsia spp. Coinfection with two or three pathogens was observed in eight dogs. Partial 16S rRNA E. canis and A. platys sequences were identical to sequences in GenBank. Partial 18S rRNA gene sequences from the Grenadian H. canis were identical to each other and had one possible mismatch (ambiguous base) from H. canis detected from Spain and Brazil. Grenadian B. c. vogeli sequences were identical to B. c. vogeli from Brazil and Japan. All of the detected pathogens are transmitted, or suspected to be transmitted, by Rhipicephalus sanguineus. Results of this study indicate that dogs from Grenada are infected with multiple tick-borne pathogens; therefore, tick-borne diseases should be included as differentials for dogs exhibiting thrombocytopenia, leukopenia, fever, or lethargy. One pathogen, E. canis, is also of potential public health significance. 相似文献
93.
94.
The records of 65 horses with peritonitis examined at two uk referral centres over a period of 12 years were reviewed. Peritonitis was defined in terms of the horse's peritoneal fluid containing more than 5 x 10(9) nucleated cells/l. Horses that had developed peritonitis after abdominal surgery or a rupture of the gastrointestinal tract were excluded. Of the 65 horses, 56 (86 per cent) survived to be discharged. Follow-up information was obtained from practice records and telephone calls to the owners for 38 of the horses. Of these, 32 (84 per cent) had survived for at least 12 months and were considered to be long-term survivors; the others six were euthanased within 12 months. Thirteen (34 per cent) of the horses discharged had experienced complications that could have been sequelae to peritonitis and eight of the 13 were euthanased. The cause of the peritonitis was identified in 15 cases; survival rates were lowest in horses with peritonitis secondary to urinary tract involvement or intra-abdominal masses. Of the other 50 cases, 47 (94 per cent) survived to discharge, but two were euthanased owing to recurrent colic. 相似文献
95.
Imogen S.F. Henderson BVSc Robert P. Franklin DVM DACVIM Pamela A. Wilkins DVM PhD DACVIM DACVECC Raymond C. Boston PhD 《Journal of Veterinary Emergency and Critical Care》2008,18(5):496-502
Objective – To investigate the association between blood lactate concentration, measured at admission and following 12–36 hours of treatment, and age, diagnosis, and survival in neonatal foals. Design – Retrospective, observational study. Setting – Two equine referral hospitals. Animals – One hundred and twelve foals ≤96 hours of age were included. Interventions – Arterial or venous blood samples were obtained from all foals at admission and surviving foals at 12–36 hours. Measurements – The lactate concentration (LAC) was recorded at 2 time points: admission (LAC‐Admission) and 12–36 hours following treatment (LAC‐24 hours). Main Results – LAC decreased by 0.05 mmol/L for each increased hour of age at presentation. Premature/dysmature foals demonstrated increased odds of nonsurvival of 55% for each 1 mmol/L increase in LAC‐Admission while foals with major diagnoses of neonatal encephalopathy (NE), enteritis and ‘Other’ had increased odds of nonsurvival of 52%, 113%, and 247%, respectively, for each 1.0 mmol/L increase in LAC. Blood‐culture positive foals had significantly lower LAC than blood culture negative foals. LAC‐Admission and LAC‐24 hours were significantly larger in nonsurviving foals. LAC‐Admission of >6.9 mmol/L and LAC‐24 hours >3.2 mmol/L, respectively, correctly classified 85.6% and 94.1% of cases as survivors or nonsurvivors. No differences were found when the 24‐hour change in LAC was investigated in terms of outcome, age at admission, or major diagnosis; however, LAC‐24 hours remained significantly associated with survival. Conclusions – Admission or persistent hyperlactatemia is associated with a nonsurvival. Younger foals, premature/dysmature foals, and foals with neonatal encephalopathy had the largest LAC. 相似文献
96.
97.
D E Henderson A M Slickman S K Henderson 《Journal of agricultural and food chemistry》1999,47(7):2563-2570
The antioxidant activity of capsaicin, as compared to BHT and melatonin, was determined by the direct measurement of lipid hydroperoxides formed upon linoleic acid autoxidation initiated by AIBN. The formation of four isomeric lipid hydroperoxides was detected after reverse-phase HPLC separation. Data from three detectors, UV absorption, glassy carbon electrode electrochemical detection, and postcolumn chemiluminescence using luminol, were compared. Capsaicin was more effective than melatonin in suppressing the formation of lipid hydroperoxides but not as effective as BHT. The formation of capsaicin and BHT dimers was observed during oxidation, and the dimers were characterized using APCI MS(n). 相似文献
98.
To study the intestinal fatty acid absorption in fish in vitro, enterocytes were isolated from the intestine of rainbow trout and incubated with an equimolar mixture of seven fatty acids [16:0, 18:1n-9, 18:2n-6, 18:3n-3, 20:4n-6, 20:5n-3 and 22:6n-3] in which the component carrying a radioactive label was varied. The fatty acid mixture was presented in the form of micelles formed by sonication with sodium taurocholate. Control studies showed that the presence of sodium taurocholate in the incubation medium caused an immediate 23% increase in the mortality of the cells but the remaining cells were viable. The effect of the bile salt on cellular permeability was evident at longer exposure periods. The proportions of 14C-labelled 20:5n-3 and 22:6n-3 present as monomeric fatty acids in the micellar solutions were higher than those of 16:0, 18:1n-9, 18:2n-6, 18:3n-3 and 20:4n-6. The rates of uptake of 14C-labelled 20:4n-6, 20:5n-3 and 22:6n-3 by enterocytes were significantly lower than those of the other fatty acid substrates over the first minute of incubation but no significant differences in uptake rate between fatty acids were obvious over a 15 min incubation period. Notable differences were observed between substrates in their distribution pattern in enterocyte lipid classes. Although most of the radioactivity from all radiolabelled substrates was recovered in triacylglycerols, the amounts of 14C- labelled 16:0, 20:4n-6, 20:5n-3 and 22:6n-3 recovered in the polar lipid fraction were higher than those of 14C-labelled C18 substrates, particularly after 15 min. Conversely, the initial esterification rates of 18:1n-9, 18:2n-6 and 18:3n-3 into triacylglycerols were significantly higher than those of 20:4n-6, 20:5n-3 and 22:6n-3. It is concluded that isolated enterocytes can be used for the study of the mechanism of intestinal fatty acid absorption in fish. 相似文献
99.
Henderson SM Baker J Williams R Gunn-Moore DA 《Journal of Feline Medicine and Surgery》2003,5(1):37-41
An 18-month-old domestic short-haired neutered male cat presented with a nodular dermal thickening on a digit. Biopsy demonstrated pyogranulomatous inflammation with moderately frequent acid-fast bacilli. A member of theMycobacterium terrae complex was isolated. There was no evidence of systemic involvement. Treatment was initiated with enrofloxacin, rifampicin and clarithromycin. After 2 months there was no longer any clinically apparent dermal thickening. Treatment was continued for a further 3 months using enrofloxacin and rifampicin. 相似文献
100.
1. Small flocks of ducks (Anasplatyrhynchos domesticus) were exposed to two stimuli, a small mobile vehicle and a walking human, to investigate their flight responses. 2. Experiment 1. Flocks were herded around an annular arena by each stimulus at 0.5 ms(-1) and the flight distance between the stimulus and the centre of the flock, and individual positions within the flock were recorded every 10 s. Flocks maintained a significantly longer distance from the human (6.0 m) than the vehicle (5.1 m) and usually did not maintain visual contact with either stimulus. Significant consistency in individual positions within the flock was found within and between trials. 3. Experiment 2. Flocks were exposed to each stimulus which approached them as they were feeding in a circular arena. The latencies for cessation and resumption of feeding were recorded and the paths followed by the flocks described. Ducks showed a significantly shorter latency to cease feeding in response to the human (4.9 s) compared with the vehicle (6.9 s). 4. Domestic ducks apparently perceive an approaching human as a greater threat than a small vehicle. The findings are discussed in relation to the development of herding robots. 相似文献