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51.
Schmidt DA Barbiers RB Ellersieck MR Ball RL Koutsos EA Griffin ME Grobler D Citino SB Bush M 《Journal of zoo and wildlife medicine》2011,42(1):33-39
Serum chemistry analyses were compared between captive and free-ranging giraffes (Giraffa camelopardalis) in an attempt to better understand some of the medical issues seen with captive giraffes. Illnesses, including peracute mortality, energy malnutrition, pancreatic disease, urolithiasis, hoof disease, and severe intestinal parasitism, may be related to zoo nutrition and management issues. Serum samples were collected from 20 captive giraffes at 10 United States institutions. Thirteen of the captive animal samples were collected from animals trained for blood collection; seven were banked samples obtained from a previous serum collection. These samples were compared with serum samples collected from 24 free-ranging giraffes in South Africa. Differences between captive and free-ranging giraffes, males and females, and adults and subadults were analyzed by using a 2 x 2 x 2 factorial and Fisher's least significant difference for mean separation; when necessary variables were ranked and analyzed via analysis of variance. Potassium and bilirubin concentrations and alanine aminotransferase (ALT) activities were different between captive and free-ranging giraffes, but all fell within normal bovid reference ranges. The average glucose concentration was significantly elevated in free-ranging giraffes (161 mg/dl) compared with captive giraffes (113 mg/dl). All giraffes in this study had glucose concentrations higher than bovine (42-75 mg/ dl) and caprine (48-76 mg/dl) reference ranges. Differences were also seen in lipase, chloride, and magnesium though these findings are likely not clinically significant. There were no differences detected between sexes. Adults had higher concentrations of potassium, total protein, globulins, and chloride and higher gamma glutamyltransferase activities, whereas subadults had higher concentrations of phosphorus. Within the captive group, nonimmobilized animals had higher concentrations of total protein and globulins. Captive giraffe diets need further investigation to determine if the differences seen in this study, especially glucose and bilirubin concentrations and ALT activities, may result in some health problems often seen in captive giraffes. 相似文献
52.
Oliver A. H. Jones Mahon L. Maguire Julian L. Griffin Young-Ho Jung Junko Shibato Randeep Rakwal Ganesh K. Agrawal Nam-Soo Jwa 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(4):539-554
A metabolomics based approach has been used to study the infection of the Hwacheong rice cultivar (Oryza sativa L. cv. Hwacheong) with compatible (KJ201) and incompatible (KJ401) strains of the rice blast fungal pathogen Magnaporthe grisea. The metabolic response of the rice plants to each strain was assessed 0, 6, 12, 24, 36, and 48 h post inoculation. Nuclear
Magnetic Resonance (NMR) spectroscopy and Gas and Liquid Chromatography Tandem Mass spectrometry (GC/LC-MS/MS) were used to
study both aqueous and organic phase metabolites, collectively resulting in the identification of 93 compounds. Clear metabolic
profiles were observed at each time point but there were no significant differences in the metabolic response elicited by
each pathogen strain until 24 h post inoculation. The largest change was found to be in alanine, which was ~30% (±9%) higher
in the leaves from the compatible, compared to the resistant, plants. Together with several other metabolites (malate, glutamine,
proline, cinnamate and an unknown sugar) alanine exhibited a good correlation between time of fungal penetration into the
leaf and the divergence of metabolite profiles in each interaction. The results indicate both that a wide range of metabolites
can be identified in rice leaves and that metabolomics has potential for the study of biochemical changes in plant-pathogen
interactions. 相似文献
53.
54.
Simulation study of the competitive ability of erect, semi-erect and prostrate cowpea (Vigna unguiculata) genotypes 总被引:1,自引:1,他引:1
Ecophysiological simulation models provide a quantitative method to predict the effects of management practices, plant characteristics and environmental factors on crop and weed growth and competition. The INTERCOM interplant competition model was parameterised, calibrated by monoculture data for three cowpea (Vigna unguiculata) genotypes that differed in growth habit, common sunflower (Helianthus annuus) and common purslane (Portulaca oleracea), and used to simulate competition of cowpea cover crops with sunflower or purslane. The simulation results were compared with observations from field competition experiments in 2003 and 2004. INTERCOM more accurately simulated actual field data for the competition of cowpea genotypes and sunflower than companion field experiments for the competition of cowpea and purslane. The validated simulation model of cowpea and sunflower at two densities was used to study the effects of cowpea growth habit on final biomass production of cowpea and sunflower. The model suggested that erect growth habit was more competitive than semi‐erect and prostrate growth habit, when cowpea genotypes were grown with sunflower. Cowpea leaf area distribution was important to higher cowpea biomass production, while cowpea height growth was important to reduce sunflower biomass. Our simulation approach is suggested as a method for crop breeders to gauge the likely success of selection for competitive crops before undertaking expensive long‐term breeding experiments. 相似文献
55.
Ultrasonically detectable characteristics of the uterus and embryo and palpable uterine tone were assessed in 10 postpartum mares. A bright fern-like pattern of ultrasonic uterine echogenicity, outlining the endometrial folds, was observed for an average of 2.1 ±0.2 days following parturition (range, 1 to 3 days). Unexpectedly, the uterus was quiescent throughout the postpartum interval, based on daily one-minute contractility scans. Contractility was maximal on Days 12 to 15 of pregnancy in both postpartum (n=7) and nonparturient (n=7) mares. The mean diameter of ultrasonically detectable intrauterine fluid collections increased (P<0.05) abruptly between days 1 and 2 postpartum and gradually decreased (P<0.05) between days 4 and 7; no collections were detected after day 16. There was no effect of day on echogenicity of the intrauterine fluid collections; on all days, fluid was relatively black or nonechogenic, suggesting that puerperal endometritis was not a problem in this group. Because the increase in intraluminal fluid occurred after parturition and in temporal association with a decrease in diameter and tone of the uterus, the fluid collections apparently represented a physiologic influx from the involuting uterus rather than residual placental fluid. Involution of the horns was completed by day 27 (formerly nongravid horn) and day 31 postpartum (formerly gravid horn), based on failure to detect further significant decreases in diameter. However, the formerly gravid horn was larger (P<0.05) in diameter than the formerly nongravid horn on each of Days 1 to 35 postpartum (end of experiment), indicating residual effects on uterine size. When averaged over both horns, uterine diameters were larger on Days 0 to 24 (Day 0=day of ovulation) of pregnancy in postpartum mares than in nonparturient mares; by Day 25, diameters were similar between statuses. By approximately Day 6 of pregnancy, uterine contractility and ultrasonic endometrial exhotexture were similar between postpartum mares and nonparturient mares. Uterine tone was greater (P<0.05) in postpartum mares than in nonparturient mares on all days between Day 0 and 25. An unexpected, transient increase in uterine tone was detected on Day 5 of pregnancy in both postpartum mares and nonparturient mares. No differences were found between reproductive statuses in patterns of embryo mobility, the day of fixation of the embryonic vesicle (postpartum, Day 15.3 ±0.4; nonparturient, Day 15.0 ±0.3), and diameter of the embryonic vesicle on the day of fixation (postpartum, 22.1 ±1.4 mm; nonparturient, 19.4 ±l.6mm). However, mean uterine tone and mean horn diameters on the side of fixation were greater (cranial and middle cornual segments; P<0.05) or tended to be greater (caudal segment; P<0.1 ) on the day of fixation in postpartum mares than in nonparturient mares. In all postpartum mares, fixation occurred in the formerly nongravid horn. Enhanced uterine tone in postpartum mares may account for the occurrence of fixation on the same day for the two reproductive statuses, despite the larger uterus in postpartum mares. 相似文献
56.
Paul B. Brown Mark E. Griffin M. Randall White 《Journal of the World Aquaculture Society》1993,24(1):80-89
Culture of hybrid striped bass has been expanding in the United States and further growth has been predicted, however, several problem areas exist, including a lack of nutritional information. This series of studies offered reciprocal cross juvenile hybrids several of the commercially available feeds and several different types of purified experimental diets. Weight gain and feed efficiency of fish fed the commercially available feeds formulated to meet the general requirements of salmonids were better than fish fed feeds formulated to meet the nutritional requirements of catfish. Experimental diets containing casein as the primary protein source were unpalatable regardless of the level of fish oil added (6 or 12%) but were accepted if 10% menhaden fish meal was added. Addition of lower levels of fish meal resulted in decreasing degrees of acceptance. Thus, the minimum level of fish meal that elicited a feeding response appeared to be between 510% of the dry diet. A crystalline amino acid test diet was palatable, and weight gain of fish fed that diet was 65–91% of the weight gain recorded for fish fed the positive control diets. Addition of L-arginine, L-methionine or L-cystine to a purified diet containing casein did not result in dietary acceptance. Whole-body proximate composition offish revealed a general trend toward increased lipid levels with increasing levels of dietary lipid. All fish exhibited microvessicular hepatopathy, regardless of diet fed. Hepatocytes contained both glycogen and lipid in the cytoplasm. 相似文献
57.
Michael Johns Addison Lawrence Joe Fox Wade Griffin 《Journal of the World Aquaculture Society》1981,12(2):305-321
One of the critical factors in commercial penaeid shrimp culture production is the availability of postlarvae to stock grow-out ponds. This study investigates the economic feasibility of rearing penaeid shrimp from nauplii to postlarvae (hatchery phase). The facility design used is based on the hatchery operated by Texas A&M university at Galveston, Texas. The Generalized Budget Simulation Model for Aquaculture developed at Texas A&M University was used for the analysis. A ten-year planning horizon was used for the analysis. Six different systems ranging in size from 5 ten-metric ton tanks to 60 ten-metric ton tanks were examined. Annual cost and return budgets were developed for the six systems assuming they operated 6 and 12 months per year. Investment costs, break-even prices and quantities, and net present value were estimated for each system. Results show that commercial hatcheries, using 10-metric ton tanks, could be profitable above and including 20 tanks for those operating only six months annually and above and including 10 tanks for those operating 12 months annually. 相似文献
58.
59.
Mycocentrospora acerina on Outdoor Lettuce. 总被引:1,自引:1,他引:0
60.
Pretreatment of rhesus macaques with nonlethal total-body x-irradiation (400 R) prolonged survival time from an average of 15 hours to 101 hours after intravenous (IV) inoculation of 50 microgram of staphylococcal enterotoxin B (SEB)/kg of body weight. Radiation exposure per se did not produce detectable cardiorenal changes; however, the longer survival after SEB challenge exposure in x-irradiated rhesus macaques was associated with improved cardiorenal functions if compared with that of nonirradiated macaques given the same dose of SEB. Total-body radiation exposure 4 days prior to IV SEB inoculation prevented typical SEB-induced decreases (where measured at 5 hours) in cardiac output, stroke volume, TcH2O, CPAH, Cosm, and urine flow, as well as increases in total peripheral and renal resistance. A theory concerning the significance of radiation-induced leukopenia on modification of SEB-induced cardiorenal functions is postulated. 相似文献