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161.
D E Brooks D J McCoy G S Martin 《Journal of the American Veterinary Medical Association》1985,187(12):1377-1379
Uterine rupture was diagnosed in 2 postpartum mares with hemorrhagic vaginal discharge. Both mares had abdominal pain, as evidenced by pawing, kicking at the abdomen, or attempting to roll. Peritoneal fluid analysis was useful in establishing a diagnosis. One mare had many RBC in the peritoneal fluid and was anemic; this mare was managed medically with oxytocin, antibiotics, and blood transfusion. The mare was able to raise her foal to weaning age. The second mare had many RBC, degenerate neutrophils, and intracellular and extracellular bacteria in peritoneal fluid. Surgical repair of the uterus was performed, and the mare was treated for peritonitis. The mare later became pregnant. 相似文献
162.
Martin Furr Mary Kay Tinker Lucy Edens 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(3):183-188
This study was conducted to develop an equation for the prediction of outcome in neonatal foals undergoing treatment in an intensive care unit (ICU). Fifty-three physical examination, historical, and clinicopathologic variables were analyzed from the records of 99 neonatal foals (<14 days of age) treated in the neonatal ICU of the Equine Medical Center. The outcome was recorded and the results were categorized into either surviving or nonsurviving groups. The mean values for the 2 groups were compared, and variables that differed significantly between the two groups were retained and used to construct a logistic regression equation. Retained variables were heart rate, temperature, and neutron phil count. The predictive equation then was tested prospectively in 2 additional groups of foals from 2 separate ICUs. The predicted outcome was compared to the actual outcome, and performance variables were calculated. Sensitivity (.83), specificity (.87), negative predictive value (.72), and positive predictive value (.93) were determined for foals from one neonatal ICU; the sensitivity (.83), specificity (.44), negative predictive value (.44), and positive predictive value (.83) were lower for foals at a second, separate ICU. 相似文献
163.
Effects of zinc sulfate (0 vs 1,142 ppm supplemental zinc from zinc sulfate) and feeding frequency (1 x vs 12x daily) on ruminal protozoa numbers, fermentation patterns and amino acid passage were investigated using four ruminally and abomasally cannulated mature Jersey steers in a 4 x 4 Latin square experiment. Steers (530 kg) were fed a 50:50 roughage:concentrate diet at 1.5 times their NEm requirement. Experimental periods were 14 d in duration; ruminal, abomasal and fecal samples were collected at 6-h intervals during the last 3 d of each period. Protozoa numbers tended to be lowest (1.82 x 10(6)/ml) in steers fed zinc 1 x and tended to be highest (3.83 x 10(6)/ml) in steers fed zinc 12 x daily (P less than .10). Frequent feeding decreased ruminal pH .24 units and increased total VFA 20.7%, ammonia 22.7% and ruminal digestion of dietary amino acids (AA) 61.6% (P less than .05). Zinc supplementation decreased ruminal digestion of dietary AA 35.8% (P less than .05) and the abomasal passage of bacterial OM and AA 21.2% (P less than .05) and increased ruminal output of amino acids as a percentage of intake 15.1% (P less than .05). Although it increased escape of dietary AA, zinc sulfate decreased postruminal passage of bacterial AA and resulted in a net negative effect on total postruminal AA passage as a percentage of intake. The effects of zinc on ruminal AA digestion may be more closely related to an interaction of zinc with dietary CP rather than to an effect of Zn on ruminal microbial populations. 相似文献
164.
J. W. Hornbeck C. T. Smith Q. W. Martin L. M. Tritton R. S. Pierce 《Forest Ecology and Management》1990,30(1-4):55-64
Effects of whole-tree clearcutting are being studied in three major forest types in the northeastern United States: a spruce-fir forest in central Maine, a northern hardwood forest in New Hampshire, and a central hardwood forest in Connecticut. At each site we sampled total and extractable nutrient capitals, inputs and outputs of nutrient ions in precipitation and streamflow, nutrient removals in harvested products, and nutrient accumulation in regrowth. Depending upon location, combined losses of nutrients in harvested products and increased leaching to streams were in the ranges of 374–558 kg ha−1 for Ca, 135–253 kg ha−1 for K, 50–65 kg ha−1 for Mg, 248–379 kg ha−1 for N, and 19–54 kg ha−1 for P. Opportunities for replacing these losses over the next rotation are best for N. Data on inputs in precipitation versus outputs in streamflow indicate that, once effects of harvest subside, most N in precipitation will stay within the forest. By contrast, Ca shows a net output of 8–15 kg ha−1 year−1 from uncut watersheds, and the added leaching losses due to harvest may have a serious impact on Ca capital. This is especially the case for the Connecticut site, where total site capital for Ca is only about 4000 kg ha−1. 相似文献
165.
The sensitivity and specificity of postbreeding plasma progesterone levels as a pregnancy test for dairy cows.
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Plasma progesterone levels on day 4 and day 8 postbreeding were measured for one hundred and eighty-four dairy cows. These two parameters (PPD4, PPD8), their absolute difference (PPDIFF) and their ratio (PPRATIO) were assessed for their ability to identify cows not conceiving, using the principles of sensitivity and specificity. PPD4 was significantly higher (p less than 0.10) and PPD8, PPDIFF and PPRATIO were significantly lower (p less than 0.01) in cows remaining open than in pregnant cows. Evaluating each parameter separately, PPDIFF greater than 3.00 units had the highest specificity, 85.7%, but a low sensitivity (27.0%). Combining two parameters using series interpretation to increase specificity resulted in the best combination of specificity (87%) and sensitivity (27%). Maximum specificity was 97% for PPD4 less than or equal to 1.00 units and PPD8 greater than 4.00 units, and also for PPD4 less than or equal to 1.00 units and PPDIFF greater than 3.00 units, but sensitivity was very low (7% and 10% respectively). Predictive values of the test results with the best specificity were evaluated; given the population pregnancy rate of 54%, none exceeded 50%, indicating that the plasma progesterone parameters were not very useful for identifying open dairy cows. 相似文献
166.
The objective of this study was to examine the effects of Aspergillus oryzae fermentation extract (Amaferm) on the in vitro ruminal fermentation of coastal bermudagrass, soluble starch and amino acids. Mixed ruminal microorganisms were incubated in anaerobic media for either 24 h (Amaferm alone, soluble starch, amino acids) or 48 h (bermudagrass). Amaferm was added to the incubation bottles (n = 4) at concentrations of 0, .4 or 1.0 g/liter. When mixed ruminal microorganisms were incubated with only Amaferm, the 1.0 g/liter concentration increased the production of hydrogen (H2; P less than .001), methane (CH4; P less than .01), acetate (P less than .05), butyrate (P less than .01), total VFA (P less than .05) and NH3 (P less than .05). Addition of both levels of Amaferm to soluble-starch fermentations tended to enhance the production of H2 (P less than .11), CH4 (P less than .15), acetate (P less than .29) and total VFA (P less than .19); propionate production was increased (P less than .10) by 1.0 g/liter Amaferm, resulting in a decrease (P less than .05) in the acetate:propionate ratio. Fermentation of amino acids plus 1.0 g/liter Amaferm enhanced the production of acetate (P less than .05), propionate (P less than .05), valerate (P less than .01) and total VFA (P less than .10) and decreased the acetate:propionate ratio (P less than .05). In addition, NH3 production tended (P less than .19) to increase with both levels of Amaferm. When bermudagrass was the substrate, few changes in fermentation products were observed with Amaferm treatment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
167.
168.
The ecological effects of planting exotic Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] in Central Europe are still poorly understood. The aim of this study was to answer the question of whether Douglas-fir affects tree specific arthropod communities in different mature forest types (Douglas-fir, spruce and beech dominated) in Southern Germany. Therefore, arthropod communities of stem and tree crown strata of Douglas-fir and spruce (Picea abies L.) were sampled in the years 1999–2001 using arboreal photo-eclectors and flight interception traps. Statistical analysis was conducted for all species and focused on conifer specialists at three levels: (1) species diversity, (2) guild structure and (3) community structure. Within the stem stratum, species diversity was significantly higher on spruce than on Douglas-fir independent of year and stand composition. This could not be explained by a single feeding guild, rather by species changing strata during the vegetation period. In contrast, species diversity in tree crowns was approximately the same for both conifer species. However, communities in Douglas-fir crowns were conspicuously different from those in spruce crowns, especially in the Douglas-fir dominated stand type. While zoophagous insects exhibited higher activity on Douglas-fir in 2000, xylophagous beetles were more abundant on spruce in 2001. In European beech stands with widely spaced Douglas-fir trees, the site specific and broad-leaved tree related fauna might be maintained. In addition, Douglas-fir with its resource of Adelges cooleyi and crowns that overtop the broad-leaved tree canopy, offer additional resources for several aphidophagous and thermophile species. 相似文献
169.
170.
Characteristic site disturbance due to harvesting and extraction machinery traffic on sensitive forest sites with peat soils 总被引:2,自引:0,他引:2
Ciaran Nugent Christopher Kanali Philip M. O. Owende Martin Nieuwenhuis Shane Ward 《Forest Ecology and Management》2003,180(1-3):85-98
The effects of wood harvesting and extraction machinery traffic on sensitive forest sites with peat soils were characterised with the objective of quantifying the threshold levels beyond which significant site impacts (compaction and rutting) would occur. The treatments involved running the machines in selected extraction racks (i.e., 3 m wide machine routes) while conducting normal wood thinning and extraction operations comprising one and two passes by the harvester and the forwarder with full payload, respectively. Soil disturbance thresholds were established by testing the level of significance of the difference in induced soil damage and compaction before and after machine traffic treatments. For volumetric soil water content lying between 10.0 and 14.9%, threshold cone penetration resistance levels for two 600/55–30.5 tyres were found to range from 594 to 640 kPa for deep-raised peat soil with initial strength lying between 524 and 581 kPa. In general, the proportion of the total rut depth data in each rack that exceeded the threshold level of 21.5 cm was about 5%. The threshold value corresponds to sinkage equivalent to 15% of the overall wheel diameter of the harvester, above which machine mobility would be hampered considerably. In addition, after harvester traffic the mean rut depth per unit rack length was 10.2×10−2 cm/m, and it ranged from 0.7 to 24.7×10−2 cm/m. 相似文献