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81.
Abigail E. Baxter Rory O. Maguire Garnett Whitehurst David Holshouser Mark Reiter 《Communications in Soil Science and Plant Analysis》2019,50(1):65-76
Soybean (Glycine max) commonly experience Mn deficiencies in the coarse-textured soils of Coastal Plain Virginia, especially under high pH conditions. The objective of this study was to investigate the ability of a novel coated fertilizer to provide Mn and B to soybeans in soils where Mn deficiency is common and B deficiency, although far less common than with Mn, is possible. A 60-d greenhouse experiment was conducted with three treatments: control, uncoated KCl, and Mn +B coated KCl applied to Bojac and Dragston sandy loams. Soil and whole plant tissue samples were collected throughout the experiment. Bojac and Dragston soils treated with the coated KCl contained 12.0 mg kg?1 and 15.8 mg kg?1 more Mehlich 1 – Mn, 21.7 mg kg?1 and 23.0 mg kg?1 more Mehlich 3 Mn, and 4.5 mg kg?1 and 4.6 mg kg?1 CaCl2 – Mn than the control and uncoated KCl, respectively. Coated KCl increased above ground tissue Mn by 42.9 mg kg?1 compared to the control and the uncoated KCl treatments in the Bojac soil, while the Dragston soil showed no significant differences in Mn tissue concentration between treatments. Above ground tissue, Mn was much lower in the Dragston soil than the Bojac, probably due to greater organic matter which chelates Mn keeping it less plant available. Boron concentrations did not differ in plant tissue or soil, regardless of the extraction method. Results indicate that the coated KCl product could consistently provide increased Mn concentration in acidic sandy soils despite varying levels of organic matter, but is not effective for B. 相似文献
82.
OBJECTIVE: To determine and analyse the immunophenotype and histological appearance of naturally occurring cases of lymphosarcoma in Australian cats. DESIGN: A prospective multi-institutional study of naturally occurring feline lymphosarcoma. METHODS: One hundred and eighteen cats were referred for diagnosis and/or management of suspected lymphosarcoma. Tissue samples for histopathological analysis and immunophenotyping were collected as biopsies or at necropsy from 109 cases. Histological classification of the neoplasms followed the Working Formulation Classification System. Four multi-species cross-reactive antibodies were used to classify tumours as having a B or T cell phenotype. RESULTS: Seventy-six (70%) cases were B cell tumours and 28 (26%) were T cell tumours. The remaining 5 (4%) specimens failed to stain with the four antibodies. Histologically, 11 (10%) cases were classified as low-grade, 72 (66%) were medium-grade and 26 (24%) were high-grade tumours. There were no significant associations between age and either histological grade or immunophenotype. Mediastinal and leukaemic cases were significantly more likely to be T cell tumours (P < 0.001 and P < 0.001, respectively). CONCLUSIONS: In contrast to previously documented studies in the cat, the majority of cases of lymphosarcoma were of B cell phenotype and intermediate histological grade. Based on our data, the histological phenotype of lymphosarcoma is unlikely to predict immunotype, nor are cases of certain immunotypes likely to be of specific histological subtype. Considered in relation to previous reports, the findings suggest that epidemiological factors operating in these cats to produce lymphosarcoma may be different to those operating in North American and UK cat populations. 相似文献
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85.
Brittany D. Kammerer Tien-Chieh Hung Randall D. Baxter Swee J. Teh 《Fish physiology and biochemistry》2016,42(1):219-232
Abiotic factors like salinity are relevant to survival of pelagic fishes of the San Francisco Bay Estuary. We tested the effects of 4 parts per thousand (ppt) salinity increases on Delta Smelt (DS) in a laboratory experiment simulating salinity increases that might occur around the low-salinity zone (LSZ) (<6 ppt). Adult DS, fed 2 % body mass per day, starting at 0.5 ppt [freshwater (FW)], were exposed to weekly step-increases of 4 ppt to a maximum of 10 ppt saltwater (SW) over 19 days, and compared to FW controls. DS (n = 12/treatment per sampling) were sampled at 24, 72, and 96 h (1, 3, and 4 days) post-salinity increase for analyses of hematocrit, plasma osmolality, muscle water content, gill chloride cell (CC) Na+/K+-ATPase (NKA) and apoptosis after being weighed and measured (n = 3 tanks per treatment). No apparent increase in length or weight occurred nor did a difference in survival. Following step-increases in SW, hematocrit increased over time. Other fish responses generally showed a pattern; specifically plasma osmolality became elevated at 1 day and diminished over 4 days in SW. Percent muscle water content (%) did not show significant changes. CCs showed increased NKA, cell size and apoptosis over time in SW, indicating that CCs turnover in DS. The cell renewal process takes days, at least over 19 days. In summary, DS are affected by salinities of the LSZ and ≤10 ppt, though they employ physiological strategies to acclimate. 相似文献
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87.
This report describes a four-day-old, full-term Connemara colt, presented for the evaluation of a progressive inability to rise unassisted. A diagnosis of nutritional muscular dystrophy was made based on muscular weakness, elevated muscle enzymes and low vitamin E, selenium and glutathione peroxidase activity. The foal was treated with intramuscular vitamin E-selenium and made a full recovery. 相似文献
88.
NI Christensen PJ Canfield PA Martin MB Krockenberger DS Spielman KL Bosward 《Australian veterinary journal》2009,87(5):175-181
Objectives To determine (1) the common types of canine splenic disorders, and the breeds affected, that are diagnosed by cytopathological and histopathological examination in Sydney, Australia and (2) the accuracy of cytopathological examination compared with histopathological examination for the diagnosis of canine splenic disorders. Design 69 cytopathological and 51 histopathological diagnoses of canine splenic disorders presented to the Veterinary Pathology Diagnostic Services, The University of Sydney during 2006 and 2007 were tabulated and analysed; 17 cases examined both cytopathologically and histopathologically during 2001–07 were also analysed. Results The most common cytopathological diagnoses were benign disorders of growth, vascular disturbances and necrosis (29%), followed by no abnormalities detectable (28%), malignant neoplasms (20%), equivocal diagnoses (20%) and inflammatory disorders (3%). The most common breeds were Kelpie crosses and mixed breeds. The most common histopathological diagnoses were benign disorders of growth, vascular disturbances and necrosis (49%), followed by malignant neoplasms (43%) and inflammatory disorders (8%). The most common breeds were German Shepherd Dogs, Boxers and Maltese Terriers. Cytopathological and histopathological diagnoses were in complete agreement in 59% of cases, partial agreement in 29% and disagreement in 12%. Conclusion Benign disorders of growth, vascular disturbances and necrosis were the most commonly diagnosed canine splenic disorders, both cytopathologically and histopathologically. Kelpie crosses presented most frequently for cytopathological examination. German Shepherd Dogs were the most common breed diagnosed histopathologically with haemangiosarcoma. Although cytopathological and histopathological splenic examinations are complementary for diagnosis, this study has shown a high correlation for complete and partial agreement between the two. 相似文献
89.
Seizures during medetomindine sedation and local anaesthesia in two dogs undergoing skin biopsy 总被引:1,自引:1,他引:0
Each of two dogs presented for multiple skin biopsies were sedated with intravenous medetomidine and lignocaine was injected subcutaneously to provide local anaesthesia for skin biopsy. One dog had a seizure during skin biopsy and again immediately following reversal of medetomidine with atipamezole. The other dog developed seizures 2 h following skin biopsy at which time the medetomidine was reversed with atipamezole. Both dogs were neurologically normal with no history of seizures prior to the procedure and remained neurologically normal for 14 weeks and 9 months, respectively, following the procedure. A drug interaction between the α2 -adrenergic agonist medetomidine and lignocaine is suspected and highlights the potential for seizures following the subcutaneous administration of relatively large doses of lignocaine under medetomidine sedation. 相似文献
90.
R. Roehe N.P. Shrestha W. Mekkawy E.M. Baxter P.W. Knap K.M. Smurthwaite S. Jarvis A.B. Lawrence S.A. Edwards 《Livestock Science》2009,121(2-3):173-181
Genetic parameters of piglet survival traits and birth weight were estimated on the first generation data of a selection experiment aimed at improving piglet survival using a multiple trait linear and threshold model. Data on 5293 piglets for survival at birth, at day one after birth and during the entire nursing period, as well as individual birth weight and litter size, were recorded in an outdoor production system. Genetic effects of piglet survival traits and birth weight were estimated based on threshold and Gaussian models, respectively, using a Bayesian approach. The statistical model included as fixed effects selection group, parity, gender, fostering, gestation length and month of farrowing and, alternatively, an adjustment for litter size. Direct genetic effects (i.e. the piglet's genetic potential) for piglet survival and birth weight were estimated separately, whereas maternal genetic and environmental effects could only be estimated for the given data structure in a combined litter effect. Posterior means of heritabilities for direct genetic effects of survival at birth, at first day after birth and the entire nursing period, as well as birth weight, were 0.08, 0.07, 0.08 and 0.20, respectively. Genetic correlations among survival traits were in the range of 0.29 to 0.40 and indicate that these traits were mainly attributable to different genetic effects. Genetic correlations between direct effects of survival traits and birth weight ranged between 0.18 and 0.23 and were reduced when weights of stillborn piglets were omitted in the analysis or the traits were adjusted for litter size. The magnitudes of direct genetic effects of survival traits are substantially higher than estimates in the literature, which may indicate that these traits have a higher genetic influence under outdoor conditions. The use of birth weight in the multiple trait estimation provided important information for the estimation of survival traits due to its favourable genetic correlations with survival, its high heritability and its high information content as a continuously measured trait. 相似文献