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121.
122.
Melanie L. Church Paul M. Barrett Julie Swenson John M. Kinsella Vasyl V. Tkach 《Veterinary ophthalmology》2013,16(1):65-72
Using slit‐lamp biomicroscopy, conjunctival biopsy, and morphological identification, a flock of four Greater rheas (Rhea americana) in Arizona were diagnosed with conjunctivitis secondary to Philophthalmus gralli (P. gralli) infection. Aquatic snails from the exhibit’s water source were identified as Melanoides tuberculatus, a known vector for P. gralli. Comparison of partial sequences of DNA regions from P. gralli adults removed from the rheas and metacercariae from the aquatic snails demonstrated a 100% match, confirming the source of infection. The flock was divided into two treatment groups: the most severely affected rheas received both manual removal of trematodes and praziquantel 1% ointment OU q12 h and the least severely affected rheas were only given praziquantel 1% ointment OU q12 h. The rheas were permanently relocated away from the infected water source and aquatic snails. Initial resolution was seen at 17 weeks in the most severely affected rhea, which had 675 adult P. gralli removed and topical praziquantel. The two rheas that only received topical praziquantel showed resolution within 3 and 15 weeks. Current recommendations for treating P. gralli include: manual removal of trematodes, topical praziquantel 1% ointment, and relocation away from infected water sources and aquatic snails. 相似文献
123.
Gillian J. McLellan Jeremy P. Kemmerling Julie A. Kiland 《Veterinary ophthalmology》2013,16(2):111-118
Objective To validate intraocular pressure (IOP) readings obtained in cats with the TonoVet® tonometer. Animals studied IOP readings obtained with the TonoVet® were compared to IOP readings determined by manometry and by the Tono‐Pen XL? in 1 normal cat and two glaucomatous cats. TonoVet® and Tono‐Pen XL? readings were also compared in a further six normal and nine glaucomatous cats. Procedures The anterior chambers of both eyes of three anesthetized cats were cannulated and IOP was varied manometrically, first increasing from 5 to 70 mmHg in 5 mmHg increments, then decreasing from 70 to 10 mmHg in 10 mmHg decrements. At each point, two observers obtained three readings each from both eyes, with both the TonoVet® and Tono‐Pen XL?. IOP was measured weekly for 8 weeks with both tonometers in six normal and nine glaucomatous unsedated cats. Data were analyzed by linear regression. Comparisons between tonometers and observers were made by paired student t‐test. Results The TonoVet® was significantly more accurate than the Tono‐Pen XL? (P = 0.001), correlating much more strongly with manometric IOP. In the clinical setting, the Tono‐Pen XL? underestimated IOP when compared with the TonoVet®. Conclusions Both the TonoVet® and Tono‐Pen XL? provide reproducible IOP measurements in cats; however, the TonoVet® provides readings much closer to the true IOP than the Tono‐Pen XL?. The TonoVet® is superior in accuracy to the Tono‐Pen XL? for the detection of ocular hypertension and/or glaucoma in cats in a clinical setting. 相似文献
124.
Surface quality and gluing performance of black spruce samples prepared by peripheral straight-edge knife planing and sanding were studied. Four wavelengths (1.5, 1.9, 3.1, and 6.5 mm) and four rake angles (15°, 20°, 25°, and 30°) were tested for peripheral planing. Three feed speeds (4, 10.5, and 17 m/min) and three grit size sandpapers (80, 100, and 120) were studied for sanding. The resulting surfaces were glued with an isocyanate adhesive and tested to evaluate their gluing performance (shear strength and percent wood failure). Results revealed that planing with a rake angle of 20° and wavelengths of up to 3.1 mm produced wood surfaces with adequate glueline shear strength. Sanding with 80-grit sandpaper produced the best glueline shear strength, regardless of feed speed. After accelerated aging, the loss of gluing performance was lower for the sanded samples compared with that of planed samples. In general, sanding process produced better wood surfaces for bonding with the adhesive studied. 相似文献
125.
Extract Sir:- I am concerned about the validity of the Complement Fixation Test (C.F.T.) for Brucella ovis in rams. 相似文献
126.
Courant F Antignac JP Laille J Monteau F Andre F Le Bizec B 《Journal of agricultural and food chemistry》2008,56(9):3176-3184
In the present study, the occurrence of the main sex steroid hormones in milk, egg, and meat was evaluated on the basis of a highly specific gas chromatography-tandem mass spectrometry measurement method. Globally, the results indicated that targeted estrogens and androgens occurred at similar levels (concentration levels in the 10-100 ng kg (-1) range) in the analyzed muscle and milk samples. The same compounds occurred at about 10-fold higher concentrations (i.e., in the 100-1000 ng kg (-1) range) in eggs and kidney samples. More precisely, egg and milk appeared as a non-negligible sources of estradiol (i.e., 2.2 +/- 0.8 and 3.1 +/- 2.0 ng day (-1), respectively), whereas testosterone exposure is caused by ingestion of meat and/or egg (i.e., 12.2 +/- 48.2 and 5.2 +/- 2.3 ng day (-1), respectively). The provided exposure data will be further exploited in the scope of a risk assessment study regarding endocrine disruption associated with these molecules. 相似文献
127.
Julie Bitz-Thorsen Katja Häkli Shripathi Bhat Kim Præbel 《Ecology of Freshwater Fish》2020,29(1):40-49
In northern Fennoscandian lakes, monophylogenetic lineages of postglacial fishes are radiating into several adaptive forms, but the speciation process is still at an incipient stage. The speciation process has received increased attention over the years, but the underlying mechanisms and drivers are still debated and poorly understood. European whitefish (Coregonus lavaretus [L.]) is the most abundant fish species in these lakes and has evolved into several ecomorphs adapted to different trophic niches and habitats. Genetic divergence has been observed among these ecomorphs, but the mechanism(s) responsible for the ongoing build-up of reproductive isolation has still to be revealed. As these systems are young in evolutionary time (<10 kyr), prezygotic and postzygotic extrinsic isolation mechanisms are thought to be more likely to contribute to the reproductive isolation than intrinsic isolation mechanisms. We determined the gonadosomatic index (GSI) of three ecomorphs in two replicated lake systems and used GSI as a proxy to investigate the prezygotic isolation mechanism, allochrony, as a driving factor of divergence in this adaptive radiation of whitefish. We found that the three ecomorphs differed in GSI values within and between lakes, suggesting different spawning times of the ecomorphs. We also show that males of one ecomorph had equal onset of maturity as another ecomorph, giving novel insights into the ongoing gene flow observed between ecomorphs. The result supports allochrony as a driver for the divergence process of whitefish ecomorphs, but more evidence is still needed to rule out that the three ecomorphs make use of different spawning grounds. 相似文献
128.
Silicon has been reported to reduce drought stress on many crops, but limited studies have evaluated this effect with rice using calcium silicate slag from the phosphorus fertilizer industry as a source of Si. A greenhouse study was performed to address this issue. Four slag rates (0, 1,000, 2,000 and 4,000 mg/kg) and two application methods (surface application and incorporation) were evaluated under two moisture regimes (flood and 50% field capacity) for drought stress mitigation in a mineral soil that is typical for rice production. Slag application significantly elevated plant‐available Si in the soil and Si accumulation in plant tissues, and tended to improve rice shoot and root biomass relative to the untreated control under both flooding and drought stress. Increased carbon isotope discrimination (△13C) and decreased proline in rice leaves subjected to drought stress indicate that this slag may reduce drought stress in rice, which was supported by restoration of foliage density, transpiration, photosynthesis rate and sugar accumulation to at or near flooded levels following the highest slag application. This study supports the usage of calcium silicate slag in rice production as it could improve Si availability and reduce drought stress. 相似文献
129.
Churchill JA 《Journal of veterinary medical education》2008,35(2):275-280
Functioning effectively as a veterinarian requires proficiency in multiple learning styles. Whether the goal is to design a nutrition course, plan a veterinary curriculum, or help students develop interpersonal, communication, and leadership skills, students benefit when content, design, and delivery are balanced to meet their learning-style preferences. An overview of four different learning style models is presented: the Myers-Briggs Type Indicator (MBTI), Kolb's Learning Style Model, the Felder-Silverman Learning Style Model, and the Herrmann Brain Dominance Instrument (HBDI). A whole-brain approach (HBDI) was used in the development and implementation of the small-animal clinical nutrition course at the University of Minnesota College of Veterinary Medicine. One educational objective of this course is to help students develop mental dexterity, increasing their proficiency in both their preferred and their less preferred modes of learning. The instructional goals are to deliver the content of the small-animal clinical nutrition course through exercises that meet the needs of learners in each thinking quadrant (left and right, cerebral and limbic) at least part of the time. Examples of exercises are presented to portray a balanced or whole-brain approach to teaching clinical nutrition. 相似文献
130.
Abdolvahab Farzan Robert M. Friendship Catherine E. Dewey Anne C. Muckle Jeff T. Gray Julie Funk 《Canadian journal of veterinary research》2008,72(1):1-6
The objective of this study was to describe the distribution of Salmonella spp. on Ontario grower-finisher pig farms. Eighty swine farms were visited from January through July 2004. On each farm, fecal samples were collected from 5 pens, 2 rectal samples and 1 pooled sample from fresh manure on the floor per pen. Salmonella was isolated from 91 (11%) of the 800 rectal samples and 73 (18%) of the 397 pooled samples. Overall, Salmonella was recovered from 37 (46%) of the 80 farms. On each positive farm, Salmonella was cultured from 1 to 7 pigs or 1 to 5 pens. Of the 37 farms, 18, 13, 5, and 1 yielded 1, 2, 3, and 4 serovars, respectively. The most common serovars were S. Typhimurium var. Copenhagen, S. Infantis, S. Typhimurium, S. Derby, S. Agona, S. Havana, and S. enterica subsp. I:Rough-O. The 3 most frequent phage types were PT 104, PT 104a, and PT 104b. There was a statistically fair agreement between samples collected directly from pigs and pooled pen samples in determining the Salmonella status at the pen and farm level (kappa = 0.6, P < 0.0001). However, in 62 pens, Salmonella status, serovars, or phage types differed between the pig and pooled pen samples. The distribution of Salmonella on the swine farms in this study indicates that, in developing an intervention strategy, priority should be given to farms positive for S. Typhimurium var. Copenhagen. Also, the variation in Salmonella status between pig and pooled pen samples deserves consideration in a sampling strategy. 相似文献