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排序方式: 共有133条查询结果,搜索用时 15 毫秒
1.
Variations in parameters of liver function and plasma progesterone related to underfeeding and ketosis in a dairy herd 总被引:2,自引:0,他引:2
Twenty-eight Norwegian Red Cattle dairy cows were fed silage ad libitum and restricted amounts of concentrates. Blood samples were collected before morning feeding, once or twice weekly, from 2 weeks before to 12 weeks after calving. Parameters of liver function, carbohydrate status and fertility were recorded in order to assess their interrelationships. Eight cows were treated for clinical ketosis. Four of these had to be treated 2 or 3 times. Aspartate aminotransferase and bilirubin showed the highest within-animal coefficients of correlation with acetoacetate. Analysis of variance revealed a significant effect of carbohydrate status (indicated by plasma acetoacetate levels) on the levels of aspartate aminotransferase, glutamate dehydrogenase and sorbitol dehydrogenase, though only a small part of the total variation was explained by this factor. The estimated volume density of liver fat in the 4th week of lactation averaged 6.0 +/- 6.4% (+/- SD) ranging from 0.1-25.1%. Liver fat content at this stage of lactation was not significantly correlated with other indicators of liver function or carbohydrate status. Cows treated for clinical ketosis had significantly lower plasma progesterone values at the time of first ketosis treatment than untreated multiparous cows. The frequency of high progesterone values (greater than 3 ng/ml) being significantly lower in treated than in untreated cows during the period from 3-5 weeks post partum, though not at later stages. In conclusion, the results revealed a significant relationship between carbohydrate status and liver function, and also between clinical ketosis and luteal function. 相似文献
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John Ellis Sheryl Gow Nicholas Pilfold Stacey Lacoste Nicholas J. Lunn Evan S. Richardson David McGeachy Megan Owen Bruce Rideout 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(7):725
Bordetella bronchiseptica is a promiscuous bacterium that infects a variety of species but has not been reported in free-ranging polar bears (Ursus maritimus). Sera from 385 polar bears from the western Hudson Bay region, 1986 to 2017, were tested for reactivity to B. bronchiseptica with enzyme-linked immunosorbent assays using anti-canine IgG and Streptococcus protein G as secondary reagents. Sera from bears had variable reactivity to B. bronchiseptica antigens, and there was no difference among bears that had a history of coming near the town of Churchill, Manitoba, and bears that did not. Although the sources of exposure were not determined, equivalent results in both groups suggest that potential exposure to humans (aside from handling during sampling) and their animals (dogs) was not an important co-factor in sero-positivity to B. bronchiseptica. 相似文献
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John Ellis Sheryl Gow Carrie Rhodes Stacey Lacoste Lyndsay Kong Kristyna Musil Elisabeth Snead 《The Canadian veterinary journal. La revue veterinaire canadienne》2016,57(5):531-534
The immune responses in control dogs [1 to 4 years of age, body condition score (BCS): 4 to 5 out of 9] were compared to those of aging dogs (based on breed and body size) either categorized as lean (BCS: 4 to 5 out of 9) or obese (BCS: 8 to 9 out of 9). Of interest were the serum titers to the following common agents found in vaccines, canine parainfluenza virus (CPIV), canine parvovirus (CPV), canine distemper virus (CDV), canine respiratory coronavirus (CRCoV), and Bordetella bronchiseptica. There were no statistical differences in the antibodies to CPIV, B. bronchispetica, and CRCoV, among the age/weight categories, nor among the age/weight categories and the time, in days, between the date of sample collection and the date of the last recorded vaccination for CPIV, B. bronchiseptica, CPV, and CDV. For CPV, the control dogs had significantly (P < 0.002) higher serum neutralization (SN) titers than the lean geriatric dogs and the obese geriatric dogs. For CDV SN titers, the only statistically significant (P = 0.01) difference was that the control dogs had higher SN titers than the lean geriatric dogs. 相似文献
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Licht BG Lin S Luo Y Hyson LL Licht MH Harper KM Sullivan SA Fernandez SA Johnston EV 《Journal of the American Veterinary Medical Association》2007,231(10):1520-1528
OBJECTIVE: To determine clinical characteristics and mode of inheritance of seizures in a family of Standard Poodles. DESIGN: Case series. ANIMALS: 90 Standard Poodles descended from the same maternal bloodline (30 with probable idiopathic epilepsy [PIE] and 60 without any history of seizures). PROCEDURES: Researchers contacted owners to determine whether dogs had ever had any seizures and, if so, the nature of any such seizures and any potential underlying causes. Dogs were considered to have PIE if they were between 6 months and 7.5 years old at the time of seizure onset and had no evidence of any underlying cause. To determine the mode of inheritance, segregation analyses were designed to allow the family to be analyzed as a whole, as opposed to as nuclear families. Competing models of inheritance were compared statistically for their ability to explain the data. RESULTS: Of the dogs with PIE, 28 (93%) had focal onset seizures with or without secondary generalization. Median age of onset was 3.7 years; 6 dogs were > 5 years old at the onset of seizures. Segregation analyses strongly suggested that PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that in this family of Standard Poodles, PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. Seizures often had focal, as opposed to generalized, onsets, and it was not uncommon for seizures to begin after 5 years of age. 相似文献
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Data for the adsorption of ethyl methylphosphonofluoridate from aqueous and the vapour phases onto montmorillonite and kaolinite clays, onto soil organic matter preparations, and onto a limited number of soils are reported. These show that the phosphonofluoridate was absorbed from the vapour phase onto the dry clay preparations by physical-chemical forces but was not adsorbed by the organic soil materials. In a general way adsorption onto dry soils could be related to their clay contents when the organic matter contents were low. Water was found to compete effectively with the phosphonofluoridate for adsorption sites, and it is concluded that this molecule will be most effectively retained by dry soils low in organic matter and rich in clay. Mechanisms for its adsorption onto clays are discussed. 相似文献
7.
Beth A Valentine Wilson K Rumbeiha Terry S Hensley Richard R Halse 《Journal of veterinary diagnostic investigation》2007,19(2):212-215
Over a 12-day period, 13 animals in a herd of 110 beef cattle developed ataxia with profound muscle fasciculations progressing to recumbency. Twelve animals (5 adults and 7 calves from 8-10 months of age) died, and 1 cow was euthanized. Hemorrhagic diarrhea occurred in some, but not all, animals. The onset of clinical signs was at least 12 hours after the cattle had gained access to contents of old buildings used for storage, and the majority of deaths occurred within 24 to 48 hours after the onset of clinical signs. Approximately 9 kg of unidentified pellets were found strewn in the barn area where the cattle had been. Autolysis considered more severe than expected for the postmortem interval, suggestive of high body temperature before death, and congestion of body tissues were the only significant findings detected in the cow that was euthanized and submitted for necropsy examination. The clinical history and lack of postmortem lesions were most consistent with toxicity. A toxic level of arsenic (6.18 ppm) was detected in the kidney, and metaldehyde was detected in the liver. The pellets were analyzed and found to contain both arsenic and metaldehyde, consistent with a discontinued molluscicidal product. 相似文献
8.
Marta I Sabara June E Larence Stacey Halayko 《Journal of veterinary diagnostic investigation》2003,15(5):447-453
The ability of a Japanese quail fibrosarcoma cell line (QT-35) to support the replication of avian metapneumoviruses belonging to the 3 subgroups A (14/1 virus), B (Colorado virus), and C (Hungary virus) enabled the development of assays for the detection and evaluation of virus-specific antibodies. On the basis of the results of enzyme-linked immunosorbent assay (ELISA), plaque reduction neutralization assay (PRNA), immunofluorescent assay (IFA), and Western blot analysis, some degree of antigenic cross-reactivity was observed between prototype viruses belonging to each of the 3 subgroups A, B, and C. The antigen produced in QT-35 cells was found to be superior with respect to its reactivity with virus-specific antibodies, as determined when used in ELISA and IFA. Standardization of both the input virus and the virus-specific antibodies in PRNA enabled a more detailed analysis of the antigenic relationship between these viruses. Specifically, it was observed that 14/1 virus shared more neutralizing regions with Hungary and Colorado viruses than did either of these viruses with 14/1 virus. In addition, Hungary virus shared comparatively fewer neutralizing epitopes with the Colorado virus than did 14/1 virus. Western blot analysis of the reactivity patterns of virus antigen, produced in QT-35 cells, with subgroup-specific antibodies identified a cross-reactive protein migrating at approximately 18 kD. These assays and the information from the Western blot will enable further analysis of avian metapneumovirus isolates to determine antigenic relationships. 相似文献
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Kochendoerfer GG Chen SY Mao F Cressman S Traviglia S Shao H Hunter CL Low DW Cagle EN Carnevali M Gueriguian V Keogh PJ Porter H Stratton SM Wiedeke MC Wilken J Tang J Levy JJ Miranda LP Crnogorac MM Kalbag S Botti P Schindler-Horvat J Savatski L Adamson JW Kung A Kent SB Bradburne JA 《Science (New York, N.Y.)》2003,299(5608):884-887
We report the design and total chemical synthesis of "synthetic erythropoiesis protein" (SEP), a 51-kilodalton protein-polymer construct consisting of a 166-amino-acid polypeptide chain and two covalently attached, branched, and monodisperse polymer moieties that are negatively charged. The ability to control the chemistry allowed us to synthesize a macromolecule of precisely defined covalent structure. SEP was homogeneous as shown by high-resolution analytical techniques, with a mass of 50,825 +/-10 daltons by electrospray mass spectrometry, and with a pI of 5.0. In cell and animal assays for erythropoiesis, SEP displayed potent biological activity and had significantly prolonged duration of action in vivo. These chemical methods are a powerful tool in the rational design of protein constructs with potential therapeutic applications. 相似文献