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91.
92.
We determined whether cows in low (LBC) or high body condition (HBC) would consume different amounts of green pine needles (Pinus ponderosa). Cows (mature; open Hereford and Hereford x Angus) were fed a maintenance basal diet (alfalfa pellets) for Exp. 1 and 2; during Exp. 3 and 4, cows were fed high-protein and high-energy diets, respectively. Experiment 5 was a grazing study on rangeland during winter in South Dakota; diets were determined by using bite counts. Mean BCS (1 = emaciated, 9 = obese) was 7.5 for HBC cows and <4.0 for LBC cows during the experiments. During Exp. 1, LBC cows consumed more (P = 0.001) pine needles than did HBC cows (5.5 +/- 0.25 vs. 1.0 +/- 0.14 g/kg of BW daily, respectively). During Exp. 2, there was a day x treatment interaction (P = 0.001) as LBC cows consumed variable, but greater, amounts of pine needles than did HBC cows (3.7 +/- 0.19 vs. 1.3 +/- 0.12 g/kg of BW daily, respectively). When fed a high-protein/low-energy diet, LBC cows ate more (P = 0.04) pine needles than did HBC cows. When fed a low-protein/high-energy diet, there was a day x treatment interaction (P = 0.001) because LBC cows consumed more pine needles than did HBC cows for the first 3 d of the study, and then consumption by LBC animals decreased during the last 4 d. These experiments suggest that the protein:energy ratio may be an important factor in the ability of cows to tolerate terpenes, and that cows were not able to sustain an increased quantity of needle consumption on a low-protein diet. During the 25-d grazing study, there was a day x treatment interaction (P = 0.001) as LBC animals selected more pine needles (up to 25% of daily bites) on some days compared with HBC cows. Weather influenced pine needle consumption because pine needle bites by LBC cows were related (r(2) = 0.60; P = 0.001) to days of greater snow depth and lower minimum daily temperatures. Both LBC and HBC cows increased selection of pine needles from trees during cold, snowy weather, but the magnitude of the increase was greater for LBC cows. The LBC cows consumed more pine needles than did HBC cows in all experiments, except when cows were fed a low-protein diet. This study indicates that both body condition and protein intake are important factors in pine needle consumption. 相似文献
93.
Arroyo LG Vengust M Dobson H Viel L 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(5):494-498
A 10-day-old quarter horse colt was presented for signs of disorientation and inability to nurse. Hydronephrosis/hydroureters, with concomitant pyelonephritis and a severe electrolytes disturbance, were diagnosed. The clinical findings closely resembled those described for a syndrome of transient pseudohypoaldosteronism in human neonates. 相似文献
94.
Ogunremi O Halbert G Mainar-Jaime R Benjamin J Pfister K Lopez-Rebollar L Georgiadis MP 《Preventive veterinary medicine》2008,83(1):41-51
We evaluated the indirect fluorescent-antibody (IFA) test and complement-fixation (CF) test for diagnosis of equine piroplasmosis in the absence of a gold standard. Using Evan's blue, we estimated the specificity of the IFA test on a parasite-free, field horse population to be 98% (95% confidence interval=97, 99). We observed an excellent test agreement (kappa=0.83) between two collaborating laboratories when the IFA test was performed on identical samples from an endemic area. Using Bayesian analysis with informative prior probability distributions, we estimated the sensitivity of the IFA test to be 92% (95% probability interval, PI=81, 98), and specificity to be 95% (95% PI=88, 99). The CF test sensitivity and specificity estimates were 28% (95% PI=15, 47) and 99% (95% PI=96, 100), respectively. We found the IFA to be superior to the CF test, and the inclusion of Evan's blue in test protocol improved the performance of the IFA test. We conclude that the IFA test for Babesia caballi is a sensitive and specific test for the diagnosis of equine piroplasmosis. 相似文献
95.
Alberta De Stefani Laurent S Garosi Fraser J McConnell Francisco J Llabres Diaz Ruth Dennis Simon R Platt 《Veterinary radiology & ultrasound》2008,49(2):135-140
Spinal epidural empyema is defined an accumulation of purulent material in the epidural space of the vertebral canal. Spinal epidural empyema should be considered as a differential diagnosis in dogs with pyrexia, spinal pain, and rapidly progressing myelopathy. Magnetic resonance (MR) imaging is the imaging test of choice in humans. Here, we describe the MR imaging features of five dogs with confirmed spinal epidural empyema. The epidural lesions appeared as high or mixed signal masses in T2-weighted (T2W) images. Increased signal within the spinal cord gray matter at the site of the lesion was detected in T2W images in all dogs. Two patterns of enhancement were detected on postcontrast T1-weighted (T1W) images. Mild to moderate peripheral enhancement was seen in three dogs and a diffuse pattern of enhancement was seen in one. Discospondylitis was identified in three dogs on T1W postcontrast images. Decompressive spinal surgery was performed in all dogs. Bacteria isolated from the abnormal epidural tissue were Enterobacter cloacae, coagulase-positive Staphylococci, Pasteurella multocida, and Escherichia coli. In one dog bacteria were not isolated. These MR imaging features, along with appropriate clinical signs, can allow prompt diagnosis and appropriate treatment planning. 相似文献
96.
Valéria Café Mar?al Anna Oevermann Tim Bley Patrizia Pfister Julien Miclard 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(1):113-115
A 4-month-old female Holstein Friesian calf was referred to the Veterinary Teaching Hospital, University of Berne, Switzerland for evaluation of ataxia, weakness, apathy and stunted growth. Clinical examination revealed generalized ataxia, propioceptive deficits, decreased menace response and sensibility. Postmortem examination did not reveal macroscopic changes of major organs. Histologically, the brain and the spinal cord lesions were characterized by polymicrocavitation, preferentially affecting the white matter fibers at the junction of grey and white matter and by the presence of Alzheimer type II cells. The liver revealed lesions consistent with a congenital portosystemic shunt, characterized by increased numbers of arteriolar profiles and hypoplasia to absence of portal veins. The pathological investigations along with the animal history and clinical signs indicated a hepatic encephalomyelopathy due to a congenital portosystemic shunt. 相似文献
97.
98.
Validation of the indirect fluorescent antibody and the complement fixation tests for the diagnosis of Theileria equi 总被引:1,自引:0,他引:1
Ogunremi O Georgiadis MP Halbert G Benjamin J Pfister K Lopez-Rebollar L 《Veterinary parasitology》2007,148(2):102-108
The indirect fluorescent antibody (IFA) test for Theileria equi was evaluated to assess test's suitability for the serological diagnosis of equine piroplasmosis, to provide performance parameters for the purpose of test validation, and to compare it with the complement fixation (CF) test. Using a protocol that included Evan's blue, the specificity of the IFA test was estimated at 99.0% for T. equi by the classical method of analysis, and 96.6% by the Bayesian method. The use of Evan's blue in the test protocol increased test specificity and contributed to an excellent test agreement between two collaborating laboratories (kappa = 0.96). Using Bayesian analysis, the sensitivity estimate for the IFA test was 89.2%. The CF test sensitivity and specificity estimates for T. equi were 63.1 and 96.4%, respectively, as determined by Bayesian analysis. The IFA test was more sensitive than the CF test but the specificity estimates were similar. 相似文献
99.
Effect of previous locoweed (Astragalus and Oxytropis species) intoxication on conditioned taste aversions in horses and sheep 总被引:1,自引:0,他引:1
Locoweed species (Astragalus and Oxytropis spp.) are a serious toxic plant problem for grazing livestock. Horses and sheep have been conditioned to avoid eating locoweed using the aversive agent LiCl. The objective of this study was to determine if previous locoweed intoxication affects food aversion learning in horses and sheep. Horses and sheep were divided into 3 treatment groups: control (not fed locoweed and not averted to a novel feed); locoweed-novel feed averted (fed locoweed and averted to a novel feed); and averted (not fed locoweed and averted to a novel feed). Animals in the locoweed-novel feed averted groups were fed locoweed during 2 periods of 21 and 14 d, respectively, with each feeding period followed by a 14-d recovery period. Animals were averted to a novel test feed at the end of the first locoweed-feeding period, and periodically evaluated for the strength and persistence of the aversion. During the first recovery period, locoweed-novel feed averted horses ate less (9.5% of amount offered) of the test feed than did control horses (99.8%) and did not generally differ from averted horses (0%). During recovery period 2, locoweed-novel feed averted horses (4.3%) differed (P = 0.001) in consumption (% of offered) of the test feed from controls (100%) and the averted group (0%). Locoweed-novel feed averted sheep differed (P = 0.001) from controls (14.4 vs. 99.5%, respectively, during recovery period 1), whereas locoweed-novel feed averted sheep did not differ (P > 0.50) from averted sheep (0.6%). During the second recovery period, control sheep (100%) differed (P < 0.05) from averted (0%) and locoweed-novel feed averted (12.2%) groups. Two intoxicated sheep (locoweed-novel feed averted) partially extinguished the aversion during the first recovery period, but an additional dose of LiCl restored the aversion. Two of 3 intoxicated horses had strong aversions that persisted without extinction; 1 horse in the locoweed-novel feed averted group had a weaker aversion. These findings suggest that horses and sheep previously intoxicated by locoweeds can form strong and persistent aversions to a novel feed, but in some animals, those aversions may not be as strong as in animals that were never intoxicated. 相似文献
100.
Kaliyamoorthy Kalidasan Nambali Valsalan Vinithkumar Dhassiah Magesh Peter Gopal Dharani Laurent Dufoss 《Marine drugs》2021,19(10)
Thraustochytrids are the most promising microbial source for the commercial production of docosahexaenoic acid (DHA) for its application in the human health, aquaculture, and nutraceutical sectors. The present study isolated 127 thraustochytrid strains from mangrove habitats of the south Andaman Islands, India to study their diversity, polyunsaturated fatty acids (PUFAs), and biotechnological potential. The predominant strains were identified as belonging to two major genera (Thraustochytrium, Aurantiochytrium) based on morphological and molecular characteristics. The strain ANVKK-06 produced the maximum biomass of 5.42 g·L−1, while ANVKK-03 exhibited the maximum total lipid (71.03%). Omega-3 PUFAs such as eicosapentaenoic acid (EPA) accumulated up to 11.03% in ANVKK-04, docosapentaenoic acid (DPA) up to 8.65% in ANVKK-07, and DHA up to 47.19% in ANVKK-06. ANVKK-06 showed the maximum scavenging activity (84.79 ± 2.30%) while ANVKK-03 and ANVKK-10 displayed the highest antibacterial activity against human and fish pathogens, S. aureus (18.69 ± 1.2 mm) and V. parahaemolyticus (18.31 ± 1.0 mm), respectively. All strains were non-toxic as evident by negative blood agar hemolysis, thus, the thraustochytrids are suggested to be a potential source of DHA for application in the health care of human and fish. 相似文献