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61.
The pharmacokinetics and dosage regimen of cefotaxime following its single subcutaneous administration (10 mg/kg) were investigated in buffalo calves. Plasma and urine samples were collected over 10 and 24 h post administration, respectively. Cefotaxime in plasma and urine was estimated by microbiological assay technique using E. coli as test organism. The pharmacokinetic profiles fitted one-compartment open model. The peak plasma levels of cefotaxime were 6.48 ± 0.52 µg/ml at 30 min and the drug was detected upto 10 h. The absorption half-life and elimination half-life were 0.173 ± 0.033 h and 1.77 ± 0.02 h, respectively. The apparent volume of distribution and total body clearance were 1.17 ± 0.10 l/kg and 0.45 ± 0.03 l/kg/h, respectively. The urinary excretion of cefotaxime in 24 h, was 5.36 ± 1.19 percent of total administrated dose. A satisfactory subcutaneous dosage regimen for cefotaxime in buffalo calves would be 13 mg/kg repeated at 12 h intervals.  相似文献   
62.
The present study was undertaken to evaluate porous hydroxyapatite (HAp), the powder of which was prepared by a novel aqueous solution combustion technique, as a bone substitute in healing bone defects in vivo, as assessed by radiologic and histopathologic methods, oxytetracycline labeling, and angiogenic features in Bengal goat. Bone defects were created in the diaphysis of the radius and either not filled (group I) or filled with a HAp strut (group II). The radiologic study in group II showed the presence of unabsorbed implants which acted as a scaffold for new bone growth across the defect, and the quality of healing of the bone defect was almost indistinguishable from the control group, in which the defect was more or less similar, although the newly formed bony tissue was more organized when HAp was used. Histologic methods showed complete normal ossification with development of Haversian canals and well-defined osteoblasts at the periphery in group II, whereas the control group had moderate fibro-collagenization and an adequate amount of marrow material, fat cells, and blood vessels. An oxytetracycline labeling study showed moderate activity of new bone formation with crossing-over of new bone trabeculae along with the presence of resorption cavities in group II, whereas in the control group, the process of new bone formation was active from both ends and the defect site appeared as a homogenous non-fluoroscent area. Angiograms of the animals in the control group showed uniform angiogenesis in the defect site with establishment of trans-transplant angiogenesis, whereas in group II there was complete trans-transplant shunting of blood vessel communication. Porous HAp ceramic prepared by an aqueous combustion technique promoted bone formation over the defect, confirming their biologic osteoconductive property.  相似文献   
63.
This retrospective study reports the presence and incidence of nasal turbinates in the nasopharynx (nasopharyngeal turbinates) in a population of brachycephalic dogs and cats exhibiting signs of upper respiratory disease. Medical records were reviewed for 53 brachycephalic dogs and 10 brachycephalic cats undergoing upper airway endoscopy. Nasopharyngeal turbinates were identified in 21% of brachycephalic animals, including 21% of dogs and 20% of cats. Pugs accounted for 32% of all dogs in the study population and 82% of dogs with nasopharyngeal turbinates. The presence of nasopharyngeal turbinates may play a role in upper airway obstruction in the brachycephalic airway syndrome.  相似文献   
64.
Trypanosoma evansi infection typically produces wasting disease, but it can also develop into a neurological or meningoencephalitis form in equids. Trypanosomiasis in horses was treated with quinapyramine sulfate, and all the 14 infected animals were recovered clinically. After clinical recovery, four animals developed a neurological form of the disease at various intervals. Two of these animals treated with diminazene aceturate recovered temporarily. Repeated attempts failed to find the parasite in the blood or the cerebrospinal fluid (CSF), but all of the animals were positive in enzyme-linked immunosorbent assay. The calculation of the antibody index (AI) in the serum and the CSF and polymerase chain reaction (PCR) analysis of the CSF and brain tissue were carried out to confirm the neuro-infection. We found PCR and AI analyses of the CSF to be useful tools in the diagnosis of the neurological form of trypanosomiasis when the organism cannot be found in the blood or CSF. The increased albumin quotient is indicative of barrier leakage due to neuroinflammation. The biochemical changes in the CSF due to nervous system trypanosomiasis include increases in the albumin quotient, total protein, and urea nitrogen. It seems to be the first report on relapse of the nervous form of trypanosomiasis in equids even after quinapyramine treatment in endemic areas.  相似文献   
65.
The applicability of ribotyping based on 16S and 23S rRNA was evaluated for molecular epidemiological studies. Forty-eight isolates of Pasteurella multocida isolated from different hosts and geographical locations and one reference isolate were ribotyped. Only four ribotypes were found. All the isolates including reference isolate from wild carnivores had the same ribotype, though they had different serotypes. The isolate from a tiger had one band in addition to the bands present in the major ribotype. The isolates from lions represented two ribotypes; of these ribotypes, one (r2) had an additional band of 3.6 kbp, which was absent in all other ribotypes. The second ribotype (r4) from a lion had one band missing (6 kbp) that was present in the other ribotypes. These isolates were further typed using ERIC-PCR and REP-PCR. With ERIC-PCR and REP-PCR, higher D values of 0.83 and 0.89 were obtained. The current study revealed that ribotyping is not a very efficient typing tool for use in molecular epidemiology for differentiation of isolates.  相似文献   
66.
The palatine tonsils of five young horses formed 10-12 cm elongated follicular structures extending from the root of the tongue on either side to the base of the epiglottis and lateral to the glossoepiglottic fold. The stratified squamous non-keratinized epithelium of the outer surface was modified into crypts as reticular epithelium by heavy infiltration of lymphoid cells from underlying lymphoid follicles. In places, lymphoid tissue reaching almost to the surface and with only one to two cell layers intact was identified as the lymphoepithelium. Langerhans cells with Birbeck granules were interspersed between epithelial cells. Lymphoid tissue organized in lymphoid follicles constituted the parenchyma of the palatine tonsil. CD4-positive cells were more numerous and CD8-positive lymphocytes less numerous compared with their distribution in the lingual tonsil. B cells and macrophages were also more numerous than in the lingual tonsil and lectins showed a different pattern of attachment. M cells were not observed. High endothelial venules with well-developed vesiculo-vacuolar organelle had structural evidence of transendothelial and interendothelial migration of lymphocytes. Striated muscles as seen in the deeper lamina propria mucosae of the lingual tonsil were absent. The immunohistological and ultrastructural characteristics of the equine palatine tonsil are similar to those of humans but differ from those of the lingual tonsil and are consistent with a role as an effector and inductor immunological organ.  相似文献   
67.
There are severe international trade restrictions on foot-and-mouth disease (FMD) affected areas. Because of endemic nature of FMD, India started FMD control programme (FMD-CP) using mass vaccination in selected states including Haryana (year 2003). Although no significant incidence of the disease was reported after launching FMD-CP in the state but in order to participate in international trade of animal and animal products, veterinary authorities have to prove that there is no FMD virus (FMDV) circulation in the animal population, for which it is necessary to differentiate the FMD infected and vaccinated animals. For this purpose, an in-house indirect ELISA utilizing baculovirus-expressed FMDV non-structural protein (NSP) 3A was used to find evidence for virus circulation (prevalence of anti-NSP 3A-specific antibodies) by examining serum samples that were collected either before start of FMD-CP or after completion of third phase (Pre-4th) of vaccination in Haryana (India). A significant reduction (P < 0.01) in prevalence of anti-NSP 3A-specific antibodies (possibly carriers) was observed 2 years after launching FMD-CP in Haryana. However, in cattle the percentage of animals with anti-NSP 3A-specific antibodies was found to be significantly higher (P < 0.01) than buffalo, both before (P < 0.01) and after (P < 0.01) launching FMD-CP in the state. The findings of this study suggest that use of FMDV vaccine in cattle and buffaloes in endemic areas reduces virus circulation (carriers) in the vaccinated herds and that the current 3ANSP-ELISA can be successfully used to monitor the FMDV circulation in endemic areas.  相似文献   
68.
We report the results of investigations that were conducted in a sheep flock in Uttaranchal, India where repeated failure of anthelmintic medication was noted. The study revealed that Haemonchus contortus in sheep had developed resistance to benzimidazoles (fenbendazole, mebendazole and albendazole), imidazothiazole (levamisole) and salicylanide (rafoxanide), while it was fully susceptible to avermectins (ivermectin). Further, the suppression of nematode egg output in faeces of sheep naturally infected with multiple anthelmintic-resistant H. contortus following treatment with ivermectin tablet (0.4 mg/kg body weight (bw), orally), ivermectin injection (1% w/v, 0.2 mg/kg bw, subcutaneously) and ivermectin pour-on (0.5 w/v, 0.5 mg/kg bw) was also studied over a period of 10 weeks post treatment. It was noted that ivermectin tablet after initial clearance of infection (faecal egg count reduction 100%), could not prevent establishment of new patent natural infection for even a single day, while ivermectin pour-on and injection prevented the establishment of new infection for 7 and 14 days post treatment, respectively. Maximum protection period (duration for which mean faecal egg count of sheep reaches 500 eggs per gram of faeces or more) of 68 days was recorded in sheep treated with injectable ivermectin, followed by pour-on (60 days) and oral (53 days) preparations.  相似文献   
69.
ABSTRACT: Picobirnaviruses (PBV) are small, non-enveloped viruses with a bisegmented double-stranded RNA genome. In this study a PBV strain, PBV/Horse/India/BG-Eq-3/2010, was identified in the faeces of a 10 month old weaned female foal with diarrhoea in January 2010 from Kolkata, India. Surprisingly, sequence comparison and phylogenetic analysis of a short stretch of the RNA dependent RNA polymerase gene revealed close genetic relatedness (> 98% nucleotide identity) to a human genogroup I PBV strain (Hu/GPBV1) detected earlier from the same part of India. Our observations together with earlier findings on genetic relatedness between human and animal PBV warrant further studies on zoonotic potential.  相似文献   
70.
Pasteurella multocida is a causative agent of many major diseases of which haemorrhagic septiciemia (HS) in cattle & a buffalo is responsible for significant losses to livestock sector in India and south Asia. The disease outcome is affected by various host- and pathogen-specific determinants. Several bacterial species-specific putative virulence factors including the capsular and virulence associated genes have been proposed to play a key role in this interaction. A total of 23 isolates of P. multocida were obtained from 335 cases of various clinically healthy and diseased cattle. These isolates were examined for capsule synthesis genes (capA, B, D, E and F) and eleven virulence associated genes (tbpA, pfhA, toxA, hgbB, hgbA, nanH, nanB, sodA, sodC, oma87 and ptfA) by PCR. A total of 19 P. multocida isolates belonging to capsular type B and 4 of capsular type A were isolated. All isolates of capsular type B harboured the virulence associated genes: tbpA, pfhA, hgbA, sodC and nanH, coding for transferrin binding protein, filamentous hemagglutinin, haemoglobin binding protein, superoxide dismutase and neuraminidases, respectively; while isolates belonging to capsular type A also carried tbpA, pfhA, hgbA and nanH genes. Only 50 % of capsular type A isolates contained sodC gene while 100 % of capsular type B isolates had sodC gene. The gene nanB and toxA were absent in all the 23 isolates. In capsular type A isolates, either sodA or sodC gene was present & these genes did not occur concurrently. The presence of virulence associated gene ptfA revealed a positive association with the disease outcome in cattle and could therefore be an important epidemiological marker gene for characterizing P. multocida isolates.  相似文献   
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