Cardiovascular disease in the equine neonate

Cardiac disease in the equine neonate occurs infrequently. Murmurs are often heard in foals and are not considered significant unless they persist beyond 4 days of age. Congenital cardiac defects are the most common form of primary cardiac disease in the foal, with ventricular septal defects occurring most frequently. Other neonatal foal diseases such as ruptured bladders, white muscle disease, neonatal respiratory distress syndrome, and septicemia have secondary cardiac involvement.     

Diseases diagnosed in broiler chicken flocks in Victoria, Australia, 1977 to 1984

During the period July 1977 to June 1984, specimens from 1402 broiler chicken flocks were submitted to the Veterinary Research Institute, Victoria, Australia for investigation of morbidity, mortality and, or, poor performance. A total of 19,450 post mortem examinations, as well as numerous ancillary tests, were performed. The findings on these flocks are presented and the consequences of some particular diseases noted.     

Diagnosis of pulmonary thromboembolism in a cat using echocardiography and pulmonary scintigraphy

A 10-year-old male cat was presented with sudden onset of respiratory difficulties. Clinical examinatlon revealed an acute dyspnoea with cyanosis associated with a left systolic heart murmur. Standard thoracic radiographs excluded pulmonary oedema and showed very few pulmonary changes given the intensity of the respiratory compromlse. Echocardiographic examination revealed hypertrophic cardiomyopathy and a thrombus In the right pulmonary artery. Pulmonary sclntlgraphy confirmed a pulmonary thromboembolism with hypovascularisatlon of the left cranial lobe and of the ventral segment of the right lobe. Conservative treatment was instituted using an antibiotic (doxycycllne), anticoagulants (heparin, coumadine) and a calcium lnhlbitor (diltiazem). The cat was given absolute rest. The general condition of the animal improved.     

Changes on carbohydrates and nitrogen content in the bark tissues induced by artificial chilling and its relationship with dormancy bud break in Prunus sp.

Stem cuttings of peach, nectarine, plum and apricot, obtained from 1-year-old shoots at leaf drop in autumn, were exposed at a constant 3.0 ± 0.1 °C to simulate different chilling accumulation treatments (0, 500, and 1000 chilling hours). A set of 10 excised shoots was forced to budbreak after chilling accumulation; a second set of 10 excised shoots was used to analyse sugars, starch, and ammonium-, nitric- and proteinaceous-nitrogen content in the bark tissues. Sorbitol, fructose and glucose were the main sugars in the bark tissues, whereas sucrose and rafinose showed the lowest quantities in all Prunus sp. studied. Sorbitol and starch concentration decreased whereas glucose and fructose concentration increased with chilling. Ammonium-nitrogen showed the more dramatic increase with medium chilling treatment, decreasing again at high chilling exposure. No modifications in proteinaceous- and nitric-nitrogen levels were observed due to chilling. Chilling treatments increasing flowering intensity showed high ammonium- and proteinaceous-nitrogen content in the bark tissues of the stem cuttings, whereas those reducing flowering intensity showed high starch and nitric-nitrogen content, in three of the four Prunus sp. studied. Ammonium-nitrogen content gives the highest correlation with flowering intensity.     

Radiometrische Untersuchungen zu Sorptionsverhalten und Abbau von 14C-PCB sowie 14C-Picloram in verschiedenen Böden

Radiometric analyses of sorption and degradation of ¹⁴C-PCB and ¹⁴C-Picloram in different soils Adsorption - desorption isothermes with ¹⁴C-PCB (2,3,4-trichlorodiphenyl) and ¹⁴C-picloram (4-amino-3,5,6-trichloropyridin-carbonic acid) were determined on 15 different soils. The rates of decomposition were determined on 3 soils. The adsorption of PCB was very intense with K-factors according to Freundlich (soil:solution = 1:20) varying from 16 to 9861. Adsorption increased with increase of organic matter and Fe-content. Picloram showed low adsorption rates, with K-factors varying from 0,01 to 18 (soil:solution = 1:4). The chemical is adsorbed by the organic matter. Decrease of pH increases the adsorption. The correlation of the K-factors with %C, % clay, pH, CEC and %0Fe_o was computed. The decomposition tests were monitored over a period of 183 days (25°C, 80% water capacity) and yielded decomposition rates of < 0,1% PCB and < 2% picloram. This difference might be due to the structure of the substance. The decomposition of PCB depends most likely on the degree of sorption. No relation between the decomposition of picloram and sorption or soil properties was found.     

Dynamic model for the effects of K fertilizer on crop growth, K-uptake and soil-K in arable cropping. 2. Field test of the model

Abstract. The validity of the model described in Greenwood & Karpinets (1997) was tested against the results of single year, multi level K fertilizer experiments. Measurements of plant mass, %K in the plant and K activity ratio in soil had been made at harvest and at intervals during the growing season on spring wheat, summer cabbage and turnips. Reasonably good agreement was obtained between these measurements and simulated values when the two 'crop' parameters (defining the dependence of critical and maximum possible %K on plant mass) were adjusted for each crop. Also good agreement was generally obtained for plant weight and plant %K at harvest in less detailed experiments on 10 other crops. Values of the two 'crop' parameters for 12 of the crops were strongly correlated with one another suggesting that a single 'crop' parameter may be all that is required to define most inter-species differences in plant-K demand.
Simulations with the model indicate that, in central England, no response of 10 crops to K fertilizer would be likely on soils containing more than 170 mg of 1 M ammonium nitrate extractable-K/kg of soil and having clay contents of between 15 and 45%. Shortcomings of the model and opportunities for advance are discussed.
A simplified version of the model runs on the Internet at: http://www.qpais.co.uk/moda-djg/potass.htm     

Bovine ocular squamous cell carcinoma: an epidemiological perspective.

Epidemiological studies on bovine ocular carcinoma were reviewed. Reports on the frequency and the distribution of the disease indicate that it is still a very prevalent and economically important disease. It is recognized throughout North America, but is more frequent in lower latitudes under range conditions. Etiological factors including ultraviolet light, circumocular apigmentation and viruses, as well as the pathogenesis, are considered in light of current knowledge on carcinogenesis of this tumor. It is likely that the induction of bovine ocular carcinoma is multifactorial and the precise roles played by each of the various factors are not yet understood.     

Professor James T. Baxter (1925–1985)

Veterinary Research Communications -     

A review of toxoplasmosis of animals in the U.S.S.R

Information on the serologic and parasitologic prevalence of Toxoplasma gondii infection in domestic and wild animals of the U.S.S.R. is reviewed. Although complement-fixing antibodies to T. gondii were widely prevalent in animals, little information is available on the presence of viable T. gondii in tissues of animals. Reports of epizootics in which T. gondii was suspected to be the causative agent of toxoplasmosis are summarized. Also, the strict economic impact of toxoplasmosis on agriculture in the U.S.S.R. needs evaluation.     

Experimental model of hypochloremic metabolic alkalosis caused by diversion of abomasal outflow in sheep

Hypochloremic metabolic alkalosis accompanied by hypokalemia and hyponatremia was induced experimentally in 7 adult sheep by diversion (loss) of gastric contents through an Ivan and Johnston cannula placed in the cranial part of the duodenum just distal to the pylorus. Cannula placement was easily accomplished, and cannulae were tolerated well by the sheep. Volume of effluent produced during the 60- to 120-hour period of diversion ranged from 7.7 to 14.9 L and tended to be greatest during the first 24 hours. All sheep became dehydrated, with mean PCV and plasma total protein concentration increases of 94.2 and 61.7%, respectively. Plasma chloride concentration decreased in linear fashion from a prediversion mean of 113 mEq/L (range, 111 to 117 mEq/L) to an end-point mean of 54 mEq/L (range, 45 to 65 mEq/L). Plasma sodium and potassium concentrations also decreased, though potassium concentration increased terminally. There were rapid increases in arterial blood pH and bicarbonate and base excess concentrations during the first 48 hours after diversion. However, during the final stages of diversion, sheep developed superimposed metabolic acidosis with increased plasma lactate concentration and high anion gap.