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1.
Abstract. Anecdotal and circumstantial evidence have suggested that the Olsen test underestimates plant-available phosphorus (P) in basaltic soils in Northern Ireland. Therefore, the ability of this test to predict plant-available P in basaltic (and non-basaltic) soils was investigated by regressing Olsen-P data against herbage P indices calculated from plant tissue test data using the diagnosis and recommendation integrated system. The average Olsen-P concentration for a range of fields situated on basaltic soils was considerably lower than the average Olsen-P concentration for a range of fields situated on non-basaltic soils, and yet mean sward P status, as given by the herbage P indices, was similar for both groups of fields. Herbage P indices were also much better correlated with Olsen-P measurements in non-basaltic soils than in basaltic soils. Furthermore, at low Olsen-P values (≶9mgPL−1 ) some swards on basaltic soils were genuinely deficient in P, while others were sufficient or even in surplus for this nutrient. The results confirm that Olsen-P is inadequate as a predictor of plant-available P in basaltic soils. It is concluded that an alternative soil test is needed to provide a reliable assessment of plant-available P in basaltic soils, to prevent overuse of fertilizer and manure P and to minimize the amounts of P entering local watercourses. 相似文献
2.
Canine distal renal tubular acidosis and urolithiasis 总被引:1,自引:0,他引:1
D J Polzin C A Osborne F W Bell 《Veterinary Clinics of North America: Small Animal Practice》1986,16(2):241-250
Distal RTA is characterized by decreased distal renal tubular hydrogen ion secretion, decreased ability to acidify urine, hypercalciuria, hyperphosphaturia, hypocitraturia, and metabolic acidosis. Because of the resulting alterations in urine composition and pH, patients with distal RTA are predisposed to urolithiasis and renal calcification. Diagnosis of distal RTA is important because it is a potentially reversible disorder that, left untreated, may cause nephrocalcinosis, recurrent urolith formation, moderate to severe metabolic acidosis, and renal failure. 相似文献
3.
This paper examines the views of members of the veterinary profession towards the change in orientation of professional practice that is occurring. It contrasts the values of veterinarians with those of doctors, dentists, lawyers and accountants. Particular attention is given to the areas of business efficiency, competition and advertising. Data was derived from self-completion questionnaires containing 40 Likert scales which were mailed to 300 members of each of the five professions. 相似文献
4.
Phalangeal and navicular bone hypoplasia and hoof malformation in the hind limbs of a foal 下载免费PDF全文
Smith DR Leach DH Bell RJ 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(1):28-30,31-34
Anatomical anomalies in the hind feet of a seven month old Appaloosa foal were identified and investigated through the use of gross anatomical dissection, radiography and angiography. Abnormalities were restricted to the distal aspect of both hind legs, the right hind leg being more severely affected. Anatomically the right foot resembled that of an equine fetus of approximately 120 days gestational age. Disruption of vascular perfusion to hoof structures was evident in both hind legs and was related to areas of abnormal bone conformation as well as to areas of abnormal ossification and calcification. Phalangeal and navicular bone hypoplasia were apparent as were soft tissue and joint anomalies. Although the etiology of the defects identified remains obscure, several theories are suggested, namely heritability, acquired defects and the possible teratogenic effects of clenbuterol. 相似文献
5.
Two cats with chronic eosinophilic skin disease were investigated. The clinical investigation of the skin disease in one cat was limited and inflammatory bowel disease was diagnosed post mortem. A history of weight loss and a palpably thickened bowel in the second cat suggested concurrent gastrointestinal disease. Diagnosis of inflammatory bowel disease was confirmed on biopsy. Treatment with azathioprine and methylprednisolone acetate resolved the signs of gastrointestinal disease, the pruritus and 95% of the skin lesions. The concurrence of eosinophilic papulocrustous dermatitis and eosinophilic bowel disease raises the possibility of their being linked bv a common aetiology or pathophysiology. 相似文献
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Fracture of the medial intercondylar eminence of the tibia in horses treated by arthroscopic fragment removal (21 horses) 下载免费PDF全文
9.
Objective To establish the prevalence of intussusceptions involving the caecum in a population of horses admitted to a university hospital for colic. Design Retrospective clinical study Methods Medical records of all horses admitted to the Massey University Veterinary Teaching Hospital between 1991 and 2004 were examined for information of those horses diagnosed with an intussusception involving the caecum. Results A total of 135 horses were admitted for colic surgery during the study period and 61 horses had a diagnosis of ileocaecal (37), caecocaecal (5) or caecocolic intussusception (19) made either at surgery or necropsy. Of the horses with ileocaecal intussusception, 32 had an incomplete hand-sewn ileocaecostomy without reduction and 29 survived to discharge. All the horses with caecocaecal intussusceptions were diagnosed preoperatively via rectal examination and/or transabdominal ultrasound: 2 were euthanased at surgery and 3 survived to discharge. In the 19 horses with caecocolic intussusceptions, manually reduction at surgery was performed in 6 and 5 of them survived to discharge. A typhlectomy was performed via a colotomy in 6 horses, 3 of which survived to discharge. Conclusions The high prevalence of intussusceptions involving the caecum seen at this referral centre may indicate a higher prevalence in New Zealand than is reported elsewhere in the world. Clinical relevance Intussusceptions involving the caecum should be considered as a differential diagnosis in horses presenting with chronic low-grade colic. Transabdominal ultrasound is useful for identifying caecocaecal and caecocolic intussusceptions. Hand-sewn side-to-side incomplete ileocaecostomy is a quick, effective and safe method of surgical treatment of ileocaecal intussusceptions. 相似文献
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