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排序方式: 共有449条查询结果,搜索用时 0 毫秒
441.
Kearns CF McKeever KH Roegner V Brady SM Malinowski K 《Veterinary journal (London, England : 1997)》2006,172(3):460-465
Plasma concentrations of adiponectin and leptin were measured in 23 mature Standardbred mares (age: 10 ± 3 years) and 12 weanling fillies (10 Quarter Horse/Belgian crossbreds and two Quarter Horses; aged: 4 ± 3 months) to test the hypothesis that adipocytokines are proportional to adiposity in horses. Rump fat thickness was measured using B-mode ultrasound and percent body fat (% fat) calculated using a published formula for the estimation of fatness in horses. Plasma adiponectin and leptin were determined using radioimmunoassay. In the absence of purified equine adiponectin or leptin, results were expressed as human equivalents (HE) of immunoreactive (ir) adipocytokines.Plasma ir-leptin HE concentration was positively correlated (r = 0.543; P < 0.001) with percent body fat and (r = 0.556; P < 0.001) to fat mass in all horses. The plasma ir-leptin HE concentration was lower (P = 0.03) in weanlings (1.90 ± 0.34 ng/mL HE) than in mature mares (3.47 ± 0.50 ng/mL HE). The ratio of ir-adiponectin HE to ir-leptin HE was negatively correlated (r = −0.621; P < 0.001) to percent fat and (r = −631; P < 0.001) to fat mass in all horses. The ratio of ir-adiponectin HE to ir-leptin HE was higher (P < 0.001) in weanlings (3.04 ± 0.51) than mature mares (1.03 ± 0.13). These data suggest that leptin is proportional while adiponectin is inversely proportional to adiposity in horses. 相似文献
442.
T DelCurto R C Cochran L R Corah A A Beharka E S Vanzant D E Johnson 《Journal of animal science》1990,68(2):532-542
Two experiments were conducted to evaluate the influence of supplemental protein concentration on the intake and utilization of dormant range forage by beef cattle. In Exp. 1,97 pregnant Hereford x Angus cows (avg wt = 454 kg) were assigned randomly to three isocaloric treatment supplements: 1) low protein (LP), 13% CP; 2) moderate protein (MP), 25% CP; and 3) high protein (HP), 39% CP. In Exp. 2, 15 ruminally and 12 esophageally cannulated steers (avg wt = 319 and 355 kg, respectively) were assigned randomly to LP, MP and HP treatments and were used in a 22-d winter grazing trial to evaluate forage intake and utilization characteristics. In Exp. 1, cow body condition (BC) and BW changes responded in linear (P less than .01) and quadratic (P less than .01) fashions to increasing protein concentration, with MP and HP displaying the least BC and BW loss from trial initiation (d 1) through d 84. From d 84 to calving (avg calving date = d 120), only the HP supplement continued to be effective in minimizing BC loss (P less than .01). Calf birth weight tended (P = .17) to increase in a linear fashion to increasing supplemental protein concentration, but calf ADG and cow reproductive efficiency were unaffected (P greater than .10). In Exp. 2, forage OM intake responded in a quadratic fashion (P less than .10), with the MP treatment having the highest NDF digestibility and ruminal OM fill. In conclusion, beef cow BC and BW losses during the winter grazing period were minimized with increasing supplemental CP concentration. Intake and utilization of dormant forage by steers were improved with moderate (26%) levels of CP in the supplement. 相似文献
443.
Perrine Benmansour Michelle L Husulak José L Bracamonte Shannon G Beazley Elanor Withnall Tanya Duke‐Novakovski 《Veterinary anaesthesia and analgesia》2014,41(4):346-356
ObjectiveTo examine the cardiopulmonary effects of infusions of remifentanil or morphine, and their influence on recovery of horses anesthetized with isoflurane and dexmedetomidine.Study designRandomized crossover study with 7-day rest periods.AnimalsSix adult horses (507 ± 61 kg).MethodsAfter the horses were sedated with xylazine, anaesthesia was induced with ketamine and diazepam, and maintained with isoflurane. After approximately 60 minutes, a dexmedetomidine infusion was started (0.25 μg kg?1 then 1.0 μg?1 kg?1 hour?1) in combination with either saline (group S), morphine (0.15 mg kg?1 then 0.1 mg kg?1 hour?1; group M), or remifentanil (6.0 μg kg?1 hour?1; group R) for 60 minutes. Mean arterial pressure, heart rate, end-tidal carbon dioxide tension, and end-tidal isoflurane concentration were recorded every 5 minutes. Core body temperature, cardiac output, right ventricular and arterial blood-gas values were measured every 15 minutes. Cardiac index, systemic vascular resistance (SVR), intrapulmonary shunt fraction, alveolar dead space, oxygen delivery and extraction ratio were calculated. Recoveries were videotaped and scored by two observers blinded to the treatment. Data were analyzed using repeated measures anova followed by Dunnett’s or Bonferroni’s significant difference test. Recovery scores were analyzed using a Kruskal–Wallis test.ResultsNo significant differences were found among groups. Compared to baseline, heart rate decreased and SVR increased significantly in all groups, and cardiac index significantly decreased in groups S and M. Hemoglobin concentration, oxygen content and oxygen delivery significantly decreased in all groups. The oxygen extraction ratio significantly increased in groups M and R. Lactate concentration significantly increased in group S. Recovery scores were similar among groups.Conclusions and clinical relevanceDexmedetomidine alone or in combination with remifentanil or morphine infusions was infused for 60 minutes without adverse effects in the 6 healthy isoflurane-anesthetized horses in this study. 相似文献
444.
Viju V. Pillai Tiffany G. Kei Shannon E. Reddy Moubani Das Christian Abratte Soon H. Cheong Vimal Selvaraj 《Animal Science Journal》2019,90(9):1149-1160
Mechanisms that direct reprogramming of differentiated somatic cells to induced pluripotent stem cells (iPSCs), albeit incomplete in understanding, are highly conserved across all mammalian species studied. Equally, proof of principle that iPSCs can be derived from domestic cattle has been reported in several publications. In our efforts to derive and study bovine iPSCs, we encountered inadequacy of methods to generate, sustain, and characterize these cells. Our results suggest that iPSC protocols optimized for mouse and human somatic cells do not effectively translate to bovine somatic cells, which show some refractoriness to reprogramming that also affects sustenance. Moreover, methods that enhance reprogramming efficiency in mouse and human cells had no effect on improving bovine cell reprogramming. Although use of retroviral vectors coding for bovine OCT4, SOX2, KLF4, cMYC, and NANOG appeared to produce consistent iPSC‐like cells from both fibroblasts and cells from the Wharton's jelly, these colonies could not be sustained. Use of bovine genes could successfully reprogram both mouse and human cells. These findings indicated either incomplete reprogramming and/or discordant/inadequate culture conditions for bovine pluripotent stem cells. Therefore, additional studies that advance core knowledge of bovine pluripotency are necessary before any anticipated iPSC‐driven bovine technologies can be realized. 相似文献
445.
S D Brandyberry R C Cochran E S Vanzant T DelCurto L R Corah 《Journal of animal science》1991,69(10):4128-4136
Two 25-d trials (late summer and early winter) were conducted to determine the influence of supplementation method on forage use and grazing behavior. Fifteen ruminally and 12 esophageally fistulated steers (316 and 400 kg, respectively) were blocked by weight and assigned randomly to one of three treatments: 1) self-feeding supplement (via Calan gates) with salt as a limiting agent; 2) daily hand-feeding supplement plus salt; and 3) daily hand-feeding supplement without salt. Supplement intake was restricted to .95 kg.steer-1.d-1 with .23 and .40 kg of salt.steer-1.d-1 during summer and winter, respectively. Neither season nor supplementation method affected forage (1.64% of BW) or total (1.89% of BW) OM intake (P greater than .10). Total OM digestibility was greater (P less than .05) in the summer, in salt-supplemented steers, and when steers were self-fed supplement. Digestibility of NDF was greater (P less than .05) in the summer than in early winter, but did not differ among treatments (P greater than .10). Fluid dilution rate was greater (P less than .05) for salt-fed and self-fed steers during the summer but similar among treatments (P greater than .10) during the winter. Total VFA concentrations did not differ among treatments during summer, but were slightly greater (P = .07) in hand-fed steers during the winter. Steers fed supplements containing salt consistently displayed lower (P less than .01) acetate:propionate ratios, and self-fed steers had lower (P less than .01) acetate:propionate ratios during the summer. Ruminal ammonia concentrations did not differ (P greater than .10) among treatments and between periods.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
446.
IMAGING DIAGNOSIS—RADIOGRAPHIC,ULTRASONOGRAPHIC, COMPUTED TOMOGRAPHIC,AND FLUOROSCOPIC APPEARANCE OF A DISTAL PELVIC LIMB ARTERIOVENOUS MALFORMATION IN A YOUNG GERMAN SHEPHERD DOG 下载免费PDF全文
Layla S. Shaikh Shannon P. Holmes Kurt T. Selberg Carla Jarrett Steven D. Holladay Justin Thomason Amanda E. Coleman 《Veterinary radiology & ultrasound》2016,57(2):E16-E21
A German shepherd puppy presented for evaluation of a suspected arteriovenous fistula on the distal aspect of the right pelvic limb. Radiographs demonstrated expansion and resorption of the tarsal and metatarsal bones, and ultrasound detected a vascular abnormality. Using computed tomographic angiography, a complex arteriovenous malformation (AVM) involving the distal tibia, tarsus, and the metatarsus and an osteochondritis dissecans (OCD) lesion of the talus were identified. Based on these findings, therapeutic limb amputation was performed. Fluoroscopic angiography, vascular casting, and dissection were then used to further characterize features of this previously unreported AVM with concurrent bony lesions and OCD. 相似文献
447.
G M Shannon O L Shotwell W F Kwolek 《Journal of the Association of Official Analytical Chemists》1983,66(3):582-586
A method was developed for the determination of aflatoxin B1 in commercially prepared feeds. The method incorporates methylene chloride and citric acid solution extraction, cleanup on a small silica gel column, and thin layer chromatography for quantitation. Commercial turkey starter, catfish chow, medicated pig starter, broiler finisher, rabbit chow, horse feed, rat chow, and dog chow were investigated. The feeds were spiked with naturally contaminated corn at 4 different levels of aflatoxin B1 (16-130 microgram/kg). Three assays were run on each of the 32 combinations of feed and levels of aflatoxin. Mean recoveries were 85.9-92.8% at levels of 16.5, 32.9, 65.8, and 131.6 micrograms/kg. The relative standard deviation per assay was 18.6%. This method is more rapid and less involved than most previously published methods for mixed feeds. 相似文献
448.
Migratory geese affect agricultural production by removing biomass and by depositing fecal nutrients. This study used 15N as a tracer to examine the quantitative effects of goose fecal N contributions on agricultural production. Barley (Hordeum vulgare cv. Datal) was grown for the production of 15N-labeled grain and straw. Two Canada geese (Branta canadensis Taverners) were fed the grain after harvest to obtain 15N-labeled and unlabeled feces. Net N mineralization and micro-plot studies both indicated that in comparison to barley grain
and straw, goose feces provided the greatest amount of available N to the soil and to the subsequent crop, and consequently
higher barley yields (59% and 62% increase, respectively). However, C mineralization was greater from grain, with 56% evolved
compared to 49% and 26% for feces and straw, respectively. Goose feces also provided the greatest addition of N for the barley
plants, with fertilizer N recovery efficiency (FNRE) of 16%, compared to FNRE of 10% from the grain amendment, and 1.2% from
the straw amendment. The amount of N available in fecal material from leftover grain consumed by grazing geese is small in
comparison to total crop needs, but is a potential source of mineral N during the critical early growth of crops grown in
cold, high-latitude soils.
Received: 16 May 1999 相似文献
449.
Andrew H. Schlueter Shannon D. Dehghanpir Bonnie Boudreaux Christopher Robinson Jose Cesar Menk P. Lima Ingeborg M. Langohr 《Journal of veterinary diagnostic investigation》2021,33(4):753
Mesotheliomas are uncommon neoplasms that arise from mesothelial cells in either the abdominal or thoracic cavities and are rarely diagnosed in cats. A 10-y-old spayed female domestic shorthair cat was presented to the Louisiana State University oncology service for evaluation of a large amount of abdominal effusion. Abdominal ultrasound identified a large mesenteric mass with numerous ill-defined nodules. An abdominocentesis was performed with cytologic and immunocytochemical findings consistent with a neoplastic effusion, with large clusters of epithelioid cells that exhibited strong cytoplasmic expression of pancytokeratin, vimentin, and Wilms tumor 1 antigens. Further testing was declined, and meloxicam was prescribed until the cat died 23 d after initial presentation. Upon postmortem examination, the omentum was contracted into a firm mass adhered to multiple organs and accompanied by numerous small white nodules throughout the abdominal cavity. On histopathology and immunohistochemistry, neoplastic cells were found throughout the abdominal cavity; 60–95% exhibited moderate-to-strong cytoplasmic immunoreactivity for cytokeratin, vimentin, and Wilms tumor 1 protein. The final diagnosis was an epithelioid mesothelioma. Our case illustrates the utility of cytology, immunocytochemistry, and its relation to histology and immunohistochemistry. We also reviewed the reported cases of feline mesothelioma. 相似文献