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991.
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Young, rapidly growing foals can be fed rations that sustain good growth rates, as long as the proper mineral balance is included. Rations causing significant postprandial hyperglycemia/hyperinsulinemia, such as sweet feeds, should be avoided if the foal is from a bloodline known to be predisposed to osteochondritis dissecans (OCD). Protein intake should not be less than 14% dry matter intake in the first year of life in order to promote optimal growth rates and development. Calcium, phosphorus, copper, and zinc intakes should also be increased in the first 2 years of life. 相似文献
993.
Modelling soil variation: past, present, and future 总被引:14,自引:0,他引:14
994.
Nitrate leaching from the Broadbalk Wheat Experiment, Rothamsted, UK, as influenced by fertilizer and manure inputs and the weather 总被引:5,自引:0,他引:5
Abstract. Nitrate leaching was measured over the eight drainage seasons spanning the nine years from 1990–1998 on the 157‐year old Broadbalk Experiment at Rothamsted, UK. The weather pattern of two dry, three wet and three dry years was the dominant factor controlling nitrogen (N) loss. Both the concentration of nitrate in the drainage waters and the amount of N leached increased with the amount of N applied, mostly because of long‐term, differential increases in soil organic matter and mineralization. On average, losses of N by leaching were 30 kg ha?1yr?1 when no more than the optimum N application was applied and were typical of amounts leached from arable land in the UK. Losses increased significantly in both amounts and as the percentage of N applied for supra‐optimal applications of N and from autumn‐applied farmyard manure (FYM). Extra spring‐applied fertilizer was very effective at increasing yields on plots given FYM in the autumn but at the expense of leaching losses three times those from optimum fertilizer N applications. Losses increased after potatoes because they left significant amounts of mineral N in the soil, and decreased after forage maize because it used applied N more effectively. Losses measured 120 years ago from identical treatments were 74% greater than current losses because of today's larger yields and more efficient varieties and management practices. Average concentrations of nitrate in drainage waters did not exceed the EU limit of 11.3 mg NO3‐N l?1 until supra‐optimal amounts of N fertilizer (>150–200 kg ha?1yr?1) were applied in spring or FYM was applied in autumn. However some drainage waters from all plots, even those that have not received fertilizer for >150 years, exceeded the limit when rain followed a dry summer and autumn. Nitrate leaching into waters will remain a problem for profitable arable farming in the drier parts of Eastern England and Europe despite increased N use efficiency. 相似文献
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To the editor: During the preparation of an article on the repair of rupture of the cranial cruciate ligament in dogs, I made a survey of the members of the American College of Veterinary Surgery in active practice with a special interest in orthopedics. They were asked to specify their preferences for treatment of this condition in small (under 16 kg) and large dogs.
A total of 111 replies were obtained. Repair in small dogs was to a great extent achieved by lateral suture stabilization by using a variety of materials such as fishing line, multifilament nonabsorbable suture, and stainless steel wire. Lateral extracapsular techniques were also used in large dogs; however, the tibial plateau leveling osteotomy was also used frequently. The data are summarized as follows: 相似文献
A total of 111 replies were obtained. Repair in small dogs was to a great extent achieved by lateral suture stabilization by using a variety of materials such as fishing line, multifilament nonabsorbable suture, and stainless steel wire. Lateral extracapsular techniques were also used in large dogs; however, the tibial plateau leveling osteotomy was also used frequently. The data are summarized as follows: 相似文献
999.
Lillian R. Aronson VMD Diplomate ACVS Clare Gregory DVM Diplomate ACVS 《Veterinary surgery : VS》1999,28(3):135-140
OBJECTIVE: To describe the clinical history of 3 cats with possible hemolytic uremic syndrome (HUS) after renal transplantation. STUDY DESIGN: This case series documents historical findings, physical examination findings, clinical pathologic features, necropsy and histopathologic findings of 3 cats with possible HUS. RESULTS: Two cats had chronic renal failure; 1 cat had acute renal failure secondary to ethylene glycol toxicity. A renal transplant was performed in each of the 3 cats without obvious problems. Complications that would support a diagnosis of HUS, including anemia, thrombocytopenia, and azotemia occurred within 24 hours in 1 cat, within 8 days in a second cat, and 2 months after transplantation in the third cat. In 2 cats, HUS was likely secondary to cyclosporine immunosuppression. In the third cat, HUS may have been secondary to allograft rejection. Renal biopsies from all 3 cats were suggestive of HUS. CONCLUSION AND CLINICAL RELEVANCE: In human beings, HUS in transplant recipients may occur secondary to immunosuppressive drugs, vascular rejection, or recurrence of original disease. Graft loss occurred in all 3 cats in this study and the mortality rate was 100%. Clinicians caring for these patients need to be aware of this disorder because early recognition and treatment is critical in the management of post-transplant HUS. 相似文献
1000.
Rebecca L. Stepien DVM MS Keith G. Benson DVM Lisa J. Forrest VMD 《Veterinary radiology & ultrasound》1999,40(6):606-610
Right lateral, left lateral and ventrodorsal radiographs were obtained in 20 normal ferrets (11 male). Three independent observers recorded measurements of the cardiac silhouette and results for each parameter were averaged. Long axis (length), short axis (width) and total of length plus width (L+W) were recorded in each view. Comparative measurements were calculated, including the ratio of L+W/length of thoracic vertebrae 5-8, and a modified vertebral heart score (VHS) method, measuring the heart in vertebral units. Measurements made in ventrodorsal views were usually larger than corresponding measurements in lateral views. Weight and most absolute measurements differed significantly between male and female ferret (P<0.05), but the differences in absolute measurements were not apparent when related to measures of body size (Ratio and modified VHS methods). Given the variability in body weight and size in ferrets, measurements of the cardiac silhouette normalized for body size may be more universally applicable than absolute measurements. 相似文献