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31.
To meet the needs of sport horses, horseshoes of various styles and materials have been implemented to enhance performance. Steel shoes are commonly used for their affordability and longevity; however, the use of aluminum horseshoes is being adopted to satisfy the various requirements of certain equestrian activities. Owing to the importance of the allure of movement in many aspects of competitive riding, the lightweight nature of aluminum horseshoes has been recognized to accentuate foreleg action. By performing a repeated-measures crossover study on nine healthy stock-type horses, the effects of these two horseshoe types on forelimb action were analyzed at the trot using two-dimensional kinematics. Horses were trotted in hand for three repetitions over a distance of 50.1 meters on days 4, 18, 32, and 46 postshoeing for two 6-week shoeing cycles. Video footage was collected and analyzed using gait analysis software (EquineTec) for each repetition. The measured stride length, fetlock extension, elbow and knee range of motion, and minimum and maximum elbow angle remained constant between treatments. However, there was a significant treatment effect on minimum carpal angle and maximum hoof height, with aluminum shoes having a larger minimum carpal angle than those in steel shoes (P < .05) and a lower maximum hoof height (P < .05). An overall 3-degree difference in minimum carpal angle and approximate 2.5-cm difference in maximum hoof height was observed between treatments. This finding is of particular importance to performance horse disciplines for which a lesser degree of knee action is desirable.  相似文献   
32.
Tropical Animal Health and Production - This study shows the absence of the world’s most common bacterial zoonoses caused by Brucella abortus and Brucella melitensis in cattle, goats and dogs...  相似文献   
33.
The objective of this preliminary study was to establish a reference range for plasma fructosamine concentration and fructosamine-albumin ratio in healthy ferrets and to compare these reference intervals to values obtained from hypoglycemic ferrets. Fructosamine concentration has been shown to reflect blood glucose concentration over the previous 1 to 2 weeks in other animal species, and may be a useful indicator of chronic hypoglycemia in ferrets diagnosed with insulinoma. Plasma fructosamine was measured with an automated colorimetric assay using nitroblue tetrazolium. Thirty-two clinically healthy and 5 hypoglycemic ferrets were included in the study. The reference interval in healthy ferrets for fructosamine was 110 (98 to 123) – 203 (191 to 218) μmol/L, and the reference interval for plasma fructosamine-albumin ratio was 5.1 (4.6 to 5.6) – 8.6 (8.2 to 9.0) μmol/g. Results for hypoglycemic ferrets were within the ranges for both fructosamine and fructosamine-albumin ratio. As there were no significant differences between the healthy and hypoglycemic ferrets, this study suggests that fructosamine concentration and fructosamine-albumin ratio are not likely to be useful in determining insulinoma-associated chronic hypoglycemia in ferrets.  相似文献   
34.
Understanding the spatial ecology of juvenile freshwater fish beyond summer months is an essential component of their life history puzzle. To this end, declines in the natural populations of sympatric Muskellunge (Esox masquinongy) and Northern Pike (Esox lucius) in the upper St. Lawrence River prompted study of spatiotemporal patterns and habitat requirements associated with earlier life stages of these congeneric, freshwater predators in fall and overwinter periods. Over 75 age-0 esocids were tagged and passively monitored using acoustic telemetry in four nursery embayments in fall and winter months from 2015 and 2017 months to elucidate spatiotemporal ecology and test hypotheses related to emigration. Presence, residency, space and habitat use were assessed and modelled against key environmental (i.e. water temperature and level) and biological (total length) covariates using mixed effect models. Muskellunge were found to spend more time in deeper, littoral regions with canopy-forming, submerged aquatic vegetation while Northern Pike aggregated in the deepest, highly vegetated region of their nursery embayment. Results suggest fish may exhibit transitionary movements in fall months and may span outwards into nearshore regions along the main river channel. Studies informing coastal restoration initiatives to increase Muskellunge production are encouraged to assess sympatric habitat use relative to prominent embayment structures and further explore depth partitioning by these young predators. With a substantial influence from water-level regulation on use of nursery habitat, future studies must work in concert with management plans aimed at producing more natural riverine cycles and thus increased recruitment of Esox species.  相似文献   
35.
African trypanosomes cause human sleeping sickness and livestock trypanosomiasis in sub-Saharan Africa. We present the sequence and analysis of the 11 megabase-sized chromosomes of Trypanosoma brucei. The 26-megabase genome contains 9068 predicted genes, including approximately 900 pseudogenes and approximately 1700 T. brucei-specific genes. Large subtelomeric arrays contain an archive of 806 variant surface glycoprotein (VSG) genes used by the parasite to evade the mammalian immune system. Most VSG genes are pseudogenes, which may be used to generate expressed mosaic genes by ectopic recombination. Comparisons of the cytoskeleton and endocytic trafficking systems with those of humans and other eukaryotic organisms reveal major differences. A comparison of metabolic pathways encoded by the genomes of T. brucei, T. cruzi, and Leishmania major reveals the least overall metabolic capability in T. brucei and the greatest in L. major. Horizontal transfer of genes of bacterial origin has contributed to some of the metabolic differences in these parasites, and a number of novel potential drug targets have been identified.  相似文献   
36.
Indole derivatives including bromoindoles have been isolated from the South Pacific marine sponges Rhopaloeides odorabile and Hyrtios sp. Their structures were established through analysis of mass spectra and 1D and 2D NMR spectroscopic data. Their potential inhibitory phospholipase A2 (PLA2), antioxidant and cytotoxic activities were evaluated. The new derivative 5,6-dibromo-l-hypaphorine (9) isolated from Hyrtios sp. revealed a weak bee venom PLA2 inhibition (IC50 0.2 mM) and a significant antioxidant activity with an Oxygen Radical Absorbance Capacity (ORAC) value of 0.22. The sesquiterpene aureol (4), also isolated from Hyrtios sp., showed the most potent antioxidant activity with an ORAC value of 0.29.  相似文献   
37.
Wheat presents an important genetic diversity that could be useful to look for cultivars with reduced allergencity. omega5-Gliadins have been described as major allergens for wheat allergic patients suffering from wheat-dependent exercise-induced anaphylaxis (WDEIA) and some cases of chronic urticaria (U). Our objective was to study the influence of genetic variability at the Gli-B1 locus encoding for omega5-gliadins on the reactivity of IgE antibodies from these patients. We selected cultivars expressing 13 alleles at Gli-B1 including a wheat/rye translocation and studied the reactivity to gliadins of a rabbit antiserum specific for omega5-gliadins and of IgE from 10 patients. The antiserum and IgE from nine patients with WDEIA and U strongly detected omega5-gliadins expressed by most of the Gli-B1 alleles but showed no or faint responses to the gliadins and secalins extracted from the translocated wheat. The selection of genotypes lacking the Gli-B1 locus may reduce wheat allergenicity.  相似文献   
38.
为了丰富玉米赤霉烯酮(ZEN)解毒菌种库,通过采集湖南省邵阳市等7个省市粮食样品,筛选获得1株能够高效降解ZEN的解淀粉芽孢杆菌NS2。采用高效液相色谱法检测降解前后ZEN的含量发现,液态发酵72 h,该菌对5 mg·L-1 ZEN标准品的降解率高达96.0%,固态发酵72 h,菌株对玉米粉中2.5 mg·L-1 ZEN标准品的降解率高达88.2%。采用高效液相色谱与四级杆飞行时间质谱联用技术检测该菌处理后的ZEN降解产物,未检测出具有毒性作用的α-玉米赤霉烯醇(α-ZOL)、β-玉米赤霉烯醇(β-ZOL)等ZEN的类似物。此外,抗菌活性试验与木聚糖酶、纤维素酶和蛋白酶活性试验显示降解菌NS2还能通过产生具有抗菌作用的次生代谢产物,抑制病原微生物大肠杆菌和鼠伤寒沙门氏菌的生长。上述结果表明,解淀粉芽孢杆菌NS2可以高效降解ZEN,具有潜在应用前景,为ZEN解毒产品的开发与应用奠定了材料基础。  相似文献   
39.
Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (>1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention.  相似文献   
40.
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