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91.
92.
Objective— To report use of a locking compression plate (LCP) for fetlock arthrodesis in Thoroughbred racehorses after catastrophic disruption of the suspensory apparatus.
Study Design— Retrospective case study.
Animals— Racing Thoroughbreds (n=6) with a catastrophic breakdown injury of the suspensory apparatus.
Methods— Medical records (2004–2006) of horses that had fetlock arthrodesis using an LCP were reviewed. Preoperative recorded variables were: age, gender, affected limb, injury type and occurrence, limb support used and time to surgery. Recorded surgical variables were: implants used and cost, surgery time, and anesthetic recovery method. Postoperative recorded variables included: treatment, physical status, complications, and outcome.
Results— Of 6 Thoroughbred racehorses that had LCP arthrodesis, 4 were sound for breeding purposes the next year and 2 horses were euthanatized (1 at 16 days, 1 at 68 days) because of proximal interphalangeal joint (PIJ) luxation. No surgical complications were associated with implant application. Postoperative complications were similar to those reported for other arthrodesis techniques.
Conclusions— LCP is a viable option for fetlock arthrodesis in Thoroughbred racehorses after catastrophic suspensory apparatus disruption.
Clinical Relevance— Adequate fetlock stability can be achieved with an LCP, and although the repair is likely more stable it is ∼3 times more expensive than using a limited contact dynamic compression plate (LC-DCP) with cortical screws. 相似文献
Study Design— Retrospective case study.
Animals— Racing Thoroughbreds (n=6) with a catastrophic breakdown injury of the suspensory apparatus.
Methods— Medical records (2004–2006) of horses that had fetlock arthrodesis using an LCP were reviewed. Preoperative recorded variables were: age, gender, affected limb, injury type and occurrence, limb support used and time to surgery. Recorded surgical variables were: implants used and cost, surgery time, and anesthetic recovery method. Postoperative recorded variables included: treatment, physical status, complications, and outcome.
Results— Of 6 Thoroughbred racehorses that had LCP arthrodesis, 4 were sound for breeding purposes the next year and 2 horses were euthanatized (1 at 16 days, 1 at 68 days) because of proximal interphalangeal joint (PIJ) luxation. No surgical complications were associated with implant application. Postoperative complications were similar to those reported for other arthrodesis techniques.
Conclusions— LCP is a viable option for fetlock arthrodesis in Thoroughbred racehorses after catastrophic suspensory apparatus disruption.
Clinical Relevance— Adequate fetlock stability can be achieved with an LCP, and although the repair is likely more stable it is ∼3 times more expensive than using a limited contact dynamic compression plate (LC-DCP) with cortical screws. 相似文献
93.
Larry R. Schaeffer 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(6):413-417
Interbull has been responsible for comparing dairy bulls across countries since the mid‐1980s. The current methodology is called MACE (multiple across country evaluations) which has been in use since 1995. Now that genomic data are being utilized in many countries, this has led to two serious problems. The first is that of preselection of young bulls such that the young animals are no longer a random sample of progeny from a sire by dam mating pair. Secondly, some countries are becoming less willing to share genomic data with Interbull. Both issues raise concern over the future of Interbull and international comparisons. This paper suggests a competition model as a potential replacement for MACE. The competition model makes pairwise comparisons between all pairs of bulls within a country and combines these differences across countries through bulls that are used in more than one country. Pedigree information is ignored as are all genomic data because bulls are treated as fixed. The model produces one international ranking of bulls averaging out any genotype by environment interactions which may exist. The competition model is illustrated by a small example. The limitations and advantages of the competition model are discussed. 相似文献
94.
Lydia J. Tong Whitney Ong Frances Hulst Gabrielle Tobias Kimberly Vinette Herrin Larry Vogelnest 《Journal of Exotic Pet Medicine》2018,27(4):53-60
Iridophores are iridescent cutaneous pigment cells found in reptiles, fish, and amphibians. Neoplasms of iridophores are rarely reported, and little is known about their behaviour, metastatic potential, and prognostic indicators. This paper reports details of the clinical course and pathological findings of metastatic iridophoroma in a veiled chameleon (Chamaeleo calyptratus) and red-barred dragon (Ctenophorus vadnappa). The veiled chameleon presented with a subcutaneous mass on the right lateral elbow and was diagnosed as an iridophoroma on fine needle aspiration. It was otherwise clinically normal. Within 35 days of excision, multiple secondary skin masses developed which were often non-pigmented and required microscopic examination to identify them as iridophoroma metastases. There were in total 54 days between the first detection of the primary mass and end stage, extensive cutaneous and visceral metastatic disease, and there had been no detectable primary mass during routine clinical examination 128 days prior to death. The red-barred dragon presented with a white sub-mandibular mass. While undergoing an excisional biopsy the animal expired, post-mortem examination revealed a cutaneous malignant iridophoroma with tumour cell clusters seen in pulmonary arterial vessels, suggesting that surgical handling of iridophoroma could precipitate the release of circulating tumour cell clusters. This is the first iridophoroma described in a red-barred dragon and the second report of a malignant iridophoroma in a veiled chameleon. Timely detection and careful excision of lizard iridophoroma may be an important factor in clinical outcome. 相似文献
95.
The prevailing paradigm is that immunosuppressed individuals are more susceptible to infection and are at higher risk of infection from Cryptosporidium oocysts if present in drinking water. To test this hypothesis, three immune conditions were examined: genetically immunocompromised T cell deficient CD-1 nude mice, B and T cell deficient Fox Chase CB-17/IcrClB SCID mice, and chemically immunosuppressed C57Bl/6 mice. Chemical immunosuppression was induced with a single subcutaneous injection of methylprednisolone acetate (MPA) at 600 mg/kg. The MPA immunosuppressed C57Bl/6 mice were characterized by a sustained decrease in circulating CD3, CD4 and CD8 T-lymphocytes of greater than 80% and a similar decrease in B-lymphocytes. A sharp rise in circulating mature segmented neutrophils followed MPA injection, dropping sharply after 10-14 days, mirroring the decrease in lymphocytes. The cessation of oocyst production after MPA was not accompanied by a radical rise in circulating CD3 or CD4 T-lymphocytes, but rather a rise in CD8 T-lymphocytes. The ID50 for the MPA immunosuppressed C57Bl/6 mice was 122 oocysts, whereas the ID50 for the C57Bl/6 immunocompetent group was 44. The genetically immunocompromised mice showed similar differences. The ID50 for CD-1 nude mice was 166 oocysts compared to 64 in CD-1 immunocompetent mice. For Fox Chase CB-17/IcrClB SCID and the immunocompetent CB-17 mice, the ID50's were 83 and 60 oocysts, respectively. These results suggest that the lack of an immune response does not increase the ability of C. muris to establish a productive infection and produce oocysts. 相似文献
96.
97.
Red and white wheats must be segregated for marketing purposes because they have different end uses. Identification of wheat color is not straightforward, and currently there is interest in characterizing red and white wheats using spectroscopic methods and chemical tests. The kernels of both red and white wheats exhibit natural fluorescence that can be readily viewed under UV light, although it is not possible to differentiate the fluorescence spectra of red and white wheats by visual inspection only. Fluorescence emission spectra in the wavelength range of 370–670 nm for 91 wheat samples consisting of 48 red (from 30 cultivars) and 43 white (from 18 cultivars) were analyzed by partial least squares (PLS) and neural networks analyses (NNA). Samples included cultivars that were difficult to classify visually as well as wheat harvested after rainfall. Classification accuracies were ≈85% for calibration and ≈72% for the validation samples by both analyses. A plot of β‐coefficient vs. wavelength in PLS analysis indicated that fluorescence of red wheat cultivars was greater than that for white wheat cultivars at 425 (±20) nm wavelength. Fluorescence of white wheat cultivars was greater than that for red cultivars at 587 (±35) nm. Fluorescence emission at ≈450 nm from wheat samples increased in intensity after treatment with NaOH. The increase was greater for red than for white wheat. Wheat harvested after rainfall also exhibited a slight increase in fluorescence. 相似文献
98.
Methyl anthranilate (MA), a food grade flavor and fragrance additive, has been reported to be an effective non-lethal bird repellent in a variety of situations. Despite the experimental success of MA, field studies have yielded widely differing levels of efficacy. Diminished efficacy in some field trials probably results from the failure of specific formulations to retain or protect the active ingredient under natural conditions. Therefore, a clearer understanding of the physical and chemical factors affecting the stability of MA is needed. We undertook a series of laboratory studies on hydrolysis, photolysis and microbial degradation of MA, the results of which could be useful in the development of appropriate formulation strategies and residue analyses. We found the n-octanol:water partition coefficient, (P) to be 84. MA is not subject to hydrolysis at 25°C in phosphate buffer media at pH 5·0, 7·0 and 9·0. MA slowly photodegrades under simulated UV ‘sunlight’. Forty-four percent of MA is lost after 432 h illuminance at 1·25 mW cm−2, which is equivalent to approximately 1200 h natural sunlight (40°N, noontime, June). Kinetic data indicate that the initial step of photolysis, subsequent to excitation, is a second-order reaction with respect to MA. A major photodegradation product appeared in an amount of about 10% of the mass balance and was determined to be an oxidized trimer of MA. MA is primarily affected by aerobic microbial degradation. For a 12:12 h light:dark, under laboratory illumination, 12% of water-solubilized material can be lost in the first seven days. Losses were 30% and 42% at 16 and 27 days, respectively. Under conditions of optimal bacterial growth (warmth and darkness) loss of MA was 22% at nine days and 100% by 20 days. The susceptibility of MA to microbial degradation is promising for the prospects of developing formulated, environmentally safe, bird repellents. 相似文献
99.
Yohei Kawasaki Yu Tanaka Keisuke Katsura Larry C. Purcell Tatsuhiko Shiraiwa 《Plant Production Science》2016,19(2):257-266
The difference in yields of cultivars may be causing difference in soybean yield between Japan and the USA. The objective of this study was to identify the effect of the cultivar on dry matter production and to reveal the key factors causing the differences in yield by focusing utilization of solar radiation in recent Japanese and US soybean cultivars. Field experiments were conducted during two seasons in Takatsuki, Japan (34°50′), and in a single season in Fayetteville (36°04′), AR, USA. Five Japanese and 10 US cultivars were observed under near-optimal conditions in order to achieve yields as close to their physiological potential as possible. The seed yield and total aboveground dry matter (TDM) were measured at maturity as long as radiation was intercepted by the canopy. The seed yield ranged from 3.10t ha?1 to 5.91t ha?1. Throughout the three environments, the seed yield of US cultivars was significantly higher than that of Japanese cultivars. The seed yield correlated with the TDM rather than the HI with correlation coefficients from .519 to .928 for the TDM vs. .175 to .800 for the HI, for each of the three environments. The higher TDM of US cultivars was caused by a higher radiation use efficiency rather than higher total intercepted radiation throughout the three environments. The seasonal change in the TDM observed in four cultivars indicated that dry matter productivity was different between cultivars, specifically during the seed-filling period. 相似文献
100.