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891.
John M. Martin Andrew C. Hogg Petrea Hofer Frank A. Manthey Michael J. Giroux 《Cereal Chemistry》2014,91(2):176-182
A small increase in amylose content may impact end‐product quality of wheat. The effect of elevated amylose content in durum wheat is not known. We surveyed 255 durum wheat accessions and found two genotypes that lacked the SGP‐A1 protein. These genotypes were crossed to Mountrail, an adapted durum genotype, to create populations segregating for the SSIIa‐Ab null allele. Our goal was to determine the influence of allelic variation at the SSIIa‐A locus on semolina properties and end‐product quality with noodles as a test product. Amylose content increased 3% and cooked noodle firmness increased 2.8 g·cm for the SSIIa‐Ab class compared with the SSIIa‐Aa class for the PI 330546 source, but no change in either trait was detected between classes for the IG 86304 source. The SSIIa‐Ab class had a 10% reduction in flour swelling compared with the SSIIa‐Aa class for both crosses. Grain protein and semolina yield did not differ between SSIIa‐A classes. The relationship between flour swelling power and noodle firmness did not differ between SSIIa‐A allelic classes within a cross. The different results for amylose content and noodle firmness between these sources may be because the two sources of the SSIIa‐Ab null mutation contributed different linkages to the segregating populations. Results show that the SSIIa‐Ab allele could be used to produce durum‐based products that are slightly more firm in texture. However, the effect of the SSIIa‐Ab allele may depend on the source. 相似文献
892.
A review of various studies on the population dynamics of feral horses (Equus caballus) in western North America reveals considerable variation both among and within individual herds, thereby rendering generalizations of questionable validity. In most populations, females commence reproduction at 3–4 years of age, with approximately one half of the mares in these age classses bearing foals in a given year. However, recent studies indicate that a modest but variable fraction (15–35%) of the 2-year olds in some populations may produces young. Among older age classes, fecundity rates generally range between 60% and 85%. Survival ratesamong foals and older animals probably average 90% and 95%, respectively, except in years of particularly adverse weather conditions (i.e. severe winters and drought). Although annual rates of increase of at least 20% have been documented in some herds, a more realistic average for most populations probably approximates 15%. Recent studies have demonstrated that population estimates based on aerial counts underestimate the actual number of animals present by a factor of 10–60%, depending upon the type of terrain and vegetation over which the census was flown. 相似文献
893.
A twenty-one-year-old male sandbar shark (Carcharhinus plumbeus) demonstrated signs of chronic weight loss even though its appetite remained unchanged. In addition, the gradual development of a red, circular lesion on its ventral body was noted. After months without any significant changes, a ventral fistula appeared revealing the tip of a wire exposed within its center. The shark was immobilized via intramuscular remote injection through dartgun with etomidate; removed from its exhibit tank; and clinically examined with radiographic imaging, a cell blood count/serum chemistry evaluation, and the use of a metal detector along the body wall. A metallic hook was identified in the coelom about 10 cm cranial to the external fistula. The shark was transferred to an isolation pool for 1 mo. A second immobilization via immersion in eugenol was conducted in order to perform a celiotomy. The hook was located in a liver lobe and was surgically removed. After a prolonged recovery from anesthesia, the shark was released into its primary tank and recovered uneventfully, although some of the skin sutures sloughed prematurely. 相似文献
894.
Water budget and annual ring growth of pines for different groundwater depth conditions Relation between annual ring width and water supply was examined for different groundwater depth in an old pine stand on a sandy soil. The quotient Ereal/Epot is a suitable parameter to quantify water stress. Multiple regression analyses were used to describe the dependence between annual ring width and water stress. Mean growth of basal area can be expressed by Ereal/Epot of the actual and previous year. This site specific function was used to quantify growth reduction affected by ground-water lowering for various soil conditions. 相似文献
895.
J. Michael Christensen Terrence R. Tiersch 《Journal of the World Aquaculture Society》1996,27(3):340-346
Abstract.— Refrigerated storage of sperm is useful for genetic study and artificial breeding of fishes. Due to the potential loss of donor males, storage is important in species such as channel catfish Icralurus punctatus from which sperm cannot be stripped. This study addresses short-term storage (at 4 C) of channel catfish sperm by evaluation of storage methods employed for other species and for cryopreservation of channel catfish sperm. The objectives were to evaluate: 1) storage of intact testes and storage of sperm suspended in an extender solution; 2) use of various storage containers with and without supplemental oxygen; 3) use of extender solution with and without the addition of an antibiotic/antimycotic cocktail; 4) use of extender solution with and without the addition of methanol; and 5) use of extender solution with and without the addition of glucose and methanol. Sperm suspended in extender solution retained motility significantly longer (9 d) than did sperm in intact testis (2 d). Sperm stored in Zip-loc® plastic bags inflated with pure oxygen retained motility significantly longer (12 d) than did sperm stored in Zip-loc® plastic bags without supplemental oxygen (7 d), or sperm stored in plastic beakers (8 d) or test tubes (8 d) without supplemental oxygen. Sperm stored with the addition of antibiotic/antimycotic cocktail or methanol retained motility significantly longer (10–12 d) than did sperm stored without additives (6–8 d). Sperm stored in extender solution without glucose retained motility significantly longer (19–21 d) than did sperm stored in extender with glucose (13–16 d). Motility was retained for as long as 21 d in sperm stored in extender solution with 5% methanol and without glucose. In each experiment, loss of motility was associated with bacterial growth. 相似文献
896.
M. Keith Chaffin DVM MS Michael A. Walker DVM Newell H. Mcarthur DVM MS PhD Elias E. Perris DVM Nora S. Matthews DVM 《Veterinary radiology & ultrasound》1997,38(2):102-111
Magnetic resonance imaging (MRI) was performed on gthe brain of 5 normal, anesthetized, neonatal (age 3-to-6 days) Quarter Horse foals. The objectives of the study were to develop a technique for imaging the brain of neonatal foals, and to ascertain their normal brain anatomy. Interavenous propofol was administered for induction and maintenance of general anesthesia. Using spin echo MR techniques, T1 weighted sagittal and transverse views, and spin density and T2 weighted transverse views were successfully made of each foal. MR images provided excellent visualization of many anatomic struictures of the brain and head. MRI of the bgrain is feasible for selected neonantal equine patients. 相似文献
897.
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
898.
Michael B. Jackson 《Pest management science》1983,14(1):25-32
A fertile soil contains sufficient water-filled pores to replenish losses by evapotranspiration and to sustain growth. However, too many such pores can be detrimental because the exchange of gases between the soil, plant roots and the aerial environment is impaired by the water they contain (waterlogging). The consequences include an accumulation of metabolically generated gases (such as ethylene), oxygen deficiency and the production of potentially toxic substances. Knowledge of these effects, and their consequences for growth, hormone production and inorganic nutrient uptake, enhance the prospects for ameliorating flooding injury by prophylactic or restorative means. Theexamples described are (a) the use of more porousmedia for plant containers in the nutrient film technique (NFT) of glasshouse crop production; (b) fungistatic, acid neutralising and oxygen-releasing seed coatings; (c) boron and nitrogen fertilisation; (d)foliar applications of cytokinins and gibberellins; (e) the inhibition of ethylene action or stimulation of ethylene production in aquatic species. 相似文献
899.
Within 15 min after application of pollen to the stigma of carnation flowers (Dianthus caryophyllus L. cultivar ‘White Sim’), ethylene (C2H4) production by the gynoecium had increased substantially. Pollen germination did not start until 1 h after pollination. Analysis of materials removed from pollen by a brief rinse with an aqueous solvent showed the presence of high concentrations of the C2H4 precursor, 1-aminocyclopropane-1-carboxylic acid (ACC). This compound, which was found to be present in pollen from a number of flower species and which increased in concentration as the anthers developed, may be an important mediator of the early response of flowers to pollination. 相似文献
900.
John K. House BVMS Bradford P. Smith John Maas V. Michael Lane Bruce C. Anderson Thomas W. Graham Michael V. Pino 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(2):105-111
Two 2-year-old Salers cattle from different herds raised on pasture were evaluated for retarded growth and diarrhea. Increase of liver enzyme activities and prolonged sulfobromophothalein (BSP) half life (T1/2) indicated liver disease with impaired liver function. Histopathologic examination of liver biopsies revealed a micronodular cirrhosis with marked deposition of hemosiderin in hepatocytes, Kupffer cells, and arterioles. Transferrin saturation (TS) and liver iron content were markedly increased, consistent with a diagnosis of hemochromatosis. Both animals were euthanatized due to deterioration in their condition. Necropsy findings included hepatomegaly and hemosiderin accumulation in the liver, lymph nodes, pancreas, spleen, thyroid, kidney, brain and other glandular tissue. Continued surveillance of the second herd (serum iron, total iron binding capacity [TIBC], unsaturated iron binding capacity [UIBC], and TS), identified a heifer as a hemochromatosis suspect in a subsequent generation. Liver biopsies from that animal revealed the same histopathologic changes as the previous 2 animals, and similar increases in liver iron content (8,700 ppm, normal range 45 to 300 ppm). The 3 affected cattle were all products of line breeding programs and shared a common ancestor. The absence of dietary iron loading in conjunction with the histopathologic and metabolic findings were consistent with a diagnosis of primary hemochromatosis. The reported disease is similar to idiopathic hemochromatosis in human beings in which there is a hereditary defect in iron metabolism. 相似文献