Retrospective assessment of tolerability and efficacy of zoledronate in the palliative treatment of cancer-bearing dogs

Zoledronate is a bisphosphonate frequently used for the treatment of hypercalcaemia of malignancy and tumour-associated bone pain in dogs, however, there is a paucity of information regarding its use in veterinary medicine. The aim of this retrospective study was to report the tolerability of zoledronate in the palliative treatment of cancer-bearing dogs and secondarily to to assess the efficacy of zoledronate for the treatment of hypercalcaemia of malignancy. Thirty-seven dogs (22 with tumour-associated bone pain and 15 with hypercalcaemia of malignancy) that received 114 zoledronate infusions were included. Tolerability was assessed by the absence of post-zoledronate hypocalcaemia or other adverse events as defined by Veterinary Cooperative Oncology Group-Common Terminology Criteria for Adverse Events criteria. Efficacy was assessed by comparison of available ionized calcium levels before and after zoledronate administration in hypercalcaemic dogs. In 79% of zoledronate infusions, no adverse events were reported. The majority of adverse events which occurred in the other 21% of infusions could be attributed to concurrent chemotherapy or the underlying neoplastic disease. There was a small but significant increase in creatinine following treatment with zoledronate, however, none of the dogs developed clinically significant renal disease. In eight hypercalcaemic dogs with available ionized calcium following zoledronate administration, ionized calcium decreased rapidly within 7 days following treatment with zoledronate. Zoledronate is well-tolerated with few recorded adverse events, however, monitoring of serum creatinine is advised. Zoledronate seems to be effective in the treatment of hypercalcaemia of malignancy.     

Irrigation of lucerne with saline groundwater on a slowly permeable,duplex soil

Summary Lucerne was irrigated for three years on a slowly permeable, duplex soil, with saline water up to 2.4 dS m^–1 without significant yield decline. Irrigation water of 4.5 dS m^–1 significantly reduced yield. Lucerne yield was most closely related to the soil ECe of the 0–15 cm depth, rather than the total rootzone, and was described by; Relative yield=100–6.5 (ECe-2.1). While lucerne roots reached depths of at least 150 cm, approximately 80% of total root length was located in the 0–60 cm depth.Increasing salinity increased the plant concentrations of sodium and chloride, however, these changes were not closely related to changes in yield.Soil salinity increased with increasing salinity of the applied water. However, during the irrigation season water penetration and the accumulation of salt within the profile was predominantly restricted to the 0–60 cm depth. No portion of the applied irrigation water was available as a leaching fraction. Any leaching of salts to the watertable, particularly below 120 cm, was due to winter rainfall rather than the application of summer irrigation water.Ripping the soil to a depth of 75 cm increased water infiltration and resulted in increased crop yields, but did not significantly affect the crop relative yield-soil ECe relationship.From the results it is proposed that on the slowly permeable duplex soils, when watertable depth is controlled, management strategies for lucerne irrigated with saline water should be based on controlling the salinity of the shallow soil depths, to 60 cm.     

Carbohydrate composition in relation to structural stability, compactibility and plasticity of two soils in a long-term experiment

The effects of tillage on soil organic carbon content, carbohydrate content, monosaccharide composition, aggregate stability, compactibility and plasticity were investigated in a field experiment on a gleysol and on a cambisol under winter barley in South-East Scotland. Two long-term treatments (direct drilling and conventional mouldboard ploughing for 22 years) were compared with short-term direct drilling and broadcast sowing plus rotavation for 5 years. Carbohydrate released sequentially to cold water, hot water, 1.0 M HCl and 0.5 M NaOH was determined after hydrolysis as reducing sugar equivalent to glucose in both fresh and air-dried samples. All other measurements were made on dry soils only. About 3% of the soluble carbohydrate was extracted by cold water, 10% by hot water, 12% by HCl and 75% by NaOH from both the dry and fresh soils. The total reducing sugars of the fractions were proportional to the total organic carbon determined by dichromate oxidation or C analysis. Organic carbon and carbohydrates were concentrated near the surface of the direct drilled soil, but were more uniformly distributed with depth in the ploughed soil. The surface soil under direct drilling was more stable, less compactible and had greater plasticity limits than under ploughing. However, particle size distributions were unaffected by tillage so that differences in soil properties were attributed to differences in the quantity and quality of organic matter. Differences in compactibility, structural stability and plasticity limits between depths and tillage treatments correlated with total carbon and with total carbohydrates. The hot water extractable carbohydrate fraction correlated best with aggregate stability and the NaOH fraction correlated best with compactibility and plastic limit. Both fractions were greatest in the long-term direct drilled soil. The hot water fraction had a galactose plus mannose over arabinose plus xylose ratio of 1.0–1.6 in comparison to 0.4–0.7 in the NaOH fraction indicating that the microbial contribution within the hot water-soluble fraction was the greater. The hot-water fraction was likely to contain more exocellular microbial polysaccharides involved in the stabilizing of soil aggregates. The hot-water and NaOH carbohydrate fractions may be good indicators of soil organic matter quality relevant to the preservation of good soil physical conditions.     

Assessing the green sea urchin (Strongylocentrotus drobachiensis) stock in Maine, USA

The green sea urchin (Strongylocentrotus drobachiensis) fishery is of great importance to Maine’s economy. The fishery took off in the late 1980s as a result of expanding export markets, but has experienced substantial decline in landings since 1992 because of large decreases in urchin stock abundance. Fishery-independent surveys have not been conducted, and no formal stock assessment has been done prior to this study. Using the data collected from the fishery and urchin life history parameters derived from scientific studies, we conducted a formal stock assessment for the urchin stock. A stochastic observation-error length-structured model is used to describe the dynamics of the sea urchin population. A robust Bayesian approach is used for estimating fishery parameters because of concerns of possible outliers in fisheries data and mis-specification of priors. This study shows that the current stock is only 10% of the virgin stock biomass and that the exploitation rate is close to 40% suggesting that a large reduction in exploitation rate is necessary.     

Clinical signs, histopathology and genetics of experimental transmission of BSE and natural scrapie to sheep and goats

This paper compares the dinical signs, histopathology, detection of PrPSc protein and PrP genetics of the transmission of BSE to sheep and goats, with the effects of the transmission of natural scrapie from a brain homogenate from a single sheep. After intracerebral and oral inoculations there were similarities in the clinical signs due to the two sources of infection, but there were differences in pathology at the end stage of disease and in the genotypes of the sheep which succumbed to the challenges. The incubation period of BSE was associated with the sheep PrP codon 171 genotype, but the natural scrapie source, despite inducing disease only in known susceptible genotypes, showed no clear association with PrP genotype.