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النتائج 1 - 10 من 29
Bioassay techniques and high-performance liquid chromatography for detection of oxytetracycline residues in tissues from calves.
1989
MacNeil J.D. | Korsrud G.O. | Naylor J.M. | Yates W.D.G.
Tissue specimens from muscle, liver, kidney, and injection sites were collected, and serum was obtained from 3 calves euthanatized on each of posttreatment days 5 and 22. Calves were treated with 6.7, 13.4, or 20 mg of oxytetracycline (OTC)/kg of body weight, IM, once daily for 3 days; these dosages are 1, 2, and 3 times the label dose, respectively. One control calf was euthanatized on each of posttreatment days 5 and 22. In treated male calves killed 2 days after the last injection, OTC residues were detected in all tissues and serum, using high-performance liquid chromatography. Tissues from all injection sites also were considered positive for antimicrobial residues, using swab test on premises (STOP), microbial inhibition test (MIT), and thin-layer chromatography-biautography (TLCB) test. Kidney tissues from a calf given 13.4 mg of OTC/kg and kidney and liver tissues from a calf given 20 mg of OTC/kg also were considered positive, using the MIT and TLCB. Results of the STOP only were considered positive for the liver and kidney of a calf given 20 mg of OTC/kg, but substitution of Saskatoon antibiotic medium-3 for the original medium (antibiotic medium-5) allowed the STOP to detect residues in these tissues from all treated calves. In female calves killed 19 days after the last injection, the STOP, MIT, and TLCB procedures revealed positive results for tissues from some injection sites, but revealed negative results for other tissues. High-performance liquid chromatographic analyses detected OTC in tissues from injection sites from all treated calves, in muscle and liver from a calf given 20 mg of OTC/kg, and in kidneys from calves given 13.4 or 20 mg of OTC/kg. The STOP, MIT, and TLCB procedures lacked the sensitivity of high-performance liquid chromatography for detection of OTC residues.
اظهر المزيد [+] اقل [-]Hypotension and cutaneous reactions associated with intravenous administration of etoposide in the dog.
1988
Ogilvie G.K. | Cockburn C.A. | Tranquilli W.J. | Reschke R.W. | Weigel R.M.
A study was undertaken to determine the pressor and toxic effects of etoposide, an antineoplastic agent, when administered IV in 0.9% sodium chloride solution (0.4 mg of etoposide/ml) over a 30-minute period to dogs at a dosage of 40 mg/m2 of body surface. On day 1, 6 adult German Shorthaired Pointers were anesthetized with halothane, and blood pressures were measured via a femoral artery catheter before, during, and after the etoposide was administered. Systolic, diastolic, and mean blood pressures of each dog increased significantly (P less than 0.01) within 30 minutes after initiation of etoposide infusion. On day 3, when the dogs were not anesthetized, etoposide was again administered to each dog, using the same dosage. Each dog developed a moderate to severe cutaneous reaction characterized by moderate to severe pruritus, urticaria, and swelling of the head and extremities that began during the second infusion of etoposide. These same cutaneous reactions were seen on day 30, when etoposide was administered to 3 of the previously treated dogs and 2 previously untreated Beagles. We concluded that the administration of the commercial preparation of etoposide is likely to cause a significant reduction in blood pressure of anesthetized dogs, and that the drug is likely to induce a moderate to severe cutaneous reaction when administered to unanesthetized dogs.
اظهر المزيد [+] اقل [-]Effects of tendon grip technique (frozen versus unfrozen) on in vitro surface strain measurements of the equine deep digital flexor tendon.
1996
Matthews G.L. | Keegan K.G. | Graham H.L.
Enzyme-linked immunosorbent assay for screening of milk samples for Salmonella typhimurium in dairy herds.
1995
Hoorfar J. | Wedderkopp A.
We investigated the ability of an antibody-specific, O antigen-based ELISA to document Salmonella typhimurium herd infections by screening of milk samples. Three cattle populations, 20 herds with no history of salmonellosis, 8 herds with history of S. typhimurium episodes within the previous 7 months, and 220 herds of unknown disease status, were tested. A herd was considered ELISA positive if at least 5% of the cows had OD values > 0.3. Among the 20 herds without history of salmonellosis, only 2 herds were ELISA positive, whereas all 8 herds with a known history of salmonellosis were ELISA positive (herd specificity, 0.9 and herd sensitivity, 1.0). A significant correlation (P < 0.001) was found between the OD values of serum and milk samples from cows in the herds with a history of salmonellosis. It was concluded that ELISA testing of individual milk samples can be used for surveillance of herds for S. typhimurium infections, but further modifications are needed to test bulk tank milk samples.
اظهر المزيد [+] اقل [-]Early insulin response to an intravenous glucose tolerance test in horses.
1994
Giraudet A. | Hinchcliff K.W. | Kohn C.W. | McKeever K.H.
Plasma insulin concentration of many species has a characteristic early or acute-phase response in the minutes after IV administration of glucose, However, the plasma insulin response of horses soon after the Iv administration of glucose has not been examined, whereas the more prolonged response has been evaluated. We examined the plasma insulin and glucose concentration responses of adult mares during the 30 minutes after rapid Iv administration of glucose (0.33 g/kg of body weight). Plasma glucose concentration peaked at 664 +/- 54 mg/dl within I minute of cessation of glucose administration, whereas insulin concentration peaked at 326 +/- 24 pmol/L at 2 minutes after the end of glucose administration. Thus, these mares had an acute insulin response, consistent with that observed in other species, including dogs, human beings, and cattle.
اظهر المزيد [+] اقل [-]Detection of viral antigens in bluetongue virus-infected ovine tissues, using the peroxidase-antiperoxidase technique.
1985
Cherrington J.M. | Ghalib H.W. | Sawyer M.M. | Osburn B.I.
Antibiotic and sulfonamide agents in bob veal calf muscle, liver, and kidney.
1991
Wilson D.J. | Franti C.E. | Norman B.B.
During the fiscal year 1988, USDA-FSIS detected 3,095 antimicrobial violations in bob veal calves, using the calf antibiotic and sulfonamide test. Of the 3,095 carcass submissions involved, 945 were tested further to identify the causative agents. The results of tests on the available kidney, liver, and muscle specimens are reported. Kidney specimens yielded a specific agent most often (71.2%), with neomycin (42.6%) being cited most among agents found in kidneys. Neomycin was found less frequently in liver (4.5%) and muscle (0.2%). Among all tissues, unidentified microbial inhibitors were either the largest or second largest category found (kidney, 10.5%; liver, 27.1%; muscle, 7.8%), and no other agent exceeded 7.0% (streptomycin in kidney). The proportion of liver and muscle specimens that had unidentified microbial inhibitors is particularly important because the next most common classes were streptomycin in liver at 5.5% and sulfamethazine in muscle at 2%. The frequency of unidentified microbial inhibitors may justify the addition of tests to the FSIS battery for identification of agents. Not all tissues were tested for sulfonamides, hence these agents are likely to have been underreported. Less than 10% of the muscle specimens evaluated yielded an agent, suggesting most calf antibiotic and sulfonamide test-positive carcasses may have been safe with regard to residues in meat, although organs might have been adulterated. Specimens for verification were not selected completely randomly from the population of all calf antibiotic and sulfonamide test-positive animals and calves selected for testing were not chosen strictly by random sampling; therefore, extrapolation of the contents of this report to the bob veal calf industry must be done with caution.
اظهر المزيد [+] اقل [-]Nutritional composition and heavy metal content in breast and thigh muscles of wild and intensively reared common pheasants (Phasianus colchicus) النص الكامل
2020
Flis, Marian | Grela, Eugeniusz R. | Żukowska, Grażyna | Gugała, Dariusz
Differing conditions in captive breeding and in the wild have impact on the mineral profile of the pheasant carcass and its heavy metal contents. This may be an indicator of environmental contamination. The study evaluated the nutritional composition and selected macro- and trace element contents (heavy metals in particular) in usable sections of pheasant breast and thigh muscles originating from captive breeding and wild birds. The tests were performed on the breast and thigh muscles of 20 wild and 20 farm bred birds from around Lublin, Poland, with equal sex representation. The nutrient and lead, cadmium, chromium, and nickel contents were determined using inductively-coupled plasma atomic emission spectroscopy. The farmed pheasants had a higher proportion of breast muscle. The thigh muscles of all birds had a higher fat content than the breast muscles (5.1 g vs. 3.4 g per kg of natural weight). The macroelement level depended on the muscle type and bird origin. The trace element content also did and gender dependence was also evident. The wild birds contained more cadmium in the breast muscles and lead in both muscles than the farm-raised ones. The high quality and usefulness of wild and farmed pheasant meat is confirmed. It has advantageous macro- and trace element contents and permissible heavy metal contents except for lead in wild birds. The heavy metal level can be a bioindicator of their environmental occurrence. In wild birds, the lead level may also reflect birdshot remnants.
اظهر المزيد [+] اقل [-]Evaluation of the effect of surgical and immunological castration of male pigs on boar taint compounds in oral fluid and fat tissue by LC-MS/MS method النص الكامل
2020
Woźniak-Sobczak, Barbara | Cybulski, Piotr | Jabłoński, Artur | Witek, Sebastian | Matraszek-Żuchowska, Iwona
An effective way of preventing undesirable boar taint in pork meat caused by the presence of androstenone, skatole and indole is surgical castration of piglets. This, however, arouses growing social opposition. An alternative method of inhibiting the development of unpleasant odour is immune castration. The aim of the study was to compare the effectiveness of both methods of castration for the elimination of the compounds responsible and to assess the suitability of oral fluid for pre-slaughter predictive testing for boar taint. The research material was pooled oral fluid and fat samples taken from gilts and surgically and immunologically castrated piglets. The samples were tested with a liquid chromatography– tandem mass spectrometry method developed in this research. The compounds giving rise to boar taint were found only sporadically above the accepted limits; only one sample of oral fluid contained skatole at a concentration above 200 μg L⁻¹ and one contained indole more concentrated than 100 μg L⁻¹. Indole above the limit value was also detected in one fat sample. In none of the tested samples was androstenone found. The results indicate the similar effectiveness of both methods of piglet castration on the reduction of compounds generating boar taint. The usefulness of testing oral fluid for the ante-mortem prediction of boar taint has not been fully confirmed and further investigation is needed.
اظهر المزيد [+] اقل [-]Detection of myxoma virus in the classical form of myxomatosis using an AGID assay: statistical assessment of the assay’s diagnostic performance النص الكامل
2020
Kwit, Ewa | Osiński, Zbigniew | Lavazza, Antonio | Rzeżutka, Artur
The aim of the study was to estimate the diagnostic sensitivity (DSe) and specificity (DSp) of an agar gel immunodiffusion (AGID) assay for detection of myxoma virus (MYXV) in the classical form of myxomatosis and to compare its diagnostic performance to that of molecular methods (IAC-PCR, OIE PCR, and OIE real-time PCR). A panel of MYXV-positive samples of tissue homogenates with low (1 PCR unit – PCRU) and high (3,125 PCRU) virus levels and outbreak samples were used for method comparison studies. The validation parameters of the AGID assay were assessed using statistical methods. The AGID attained DSe of 0.65 (CI₉₅%: 0.53–0.76), DSp of 1.00 (CI₉₅%: 0.40–1.00), and accuracy of 0.67 (CI₉₅%: 0.55–0.76). The assay confirmed its diagnostic usefulness primarily for testing samples containing ≥3,125 PCRU of MYXV DNA. However, in the assaying of samples containing <3,125 PCRU of the virus there was a higher probability of getting false negative results, and only molecular methods showed a 100% sensitivity for samples with low (1 PCRU) virus concentration. The overall concordance of the results between AGID and IAC-PCR was fair (ĸ = 0.40). Full concordance of the results was observed for OIE PCR and OIE real-time PCR when control reference material was analysed. Findings from this study suggest that AGID can be used with some limitations as a screening tool for detection of MYXV infections.
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