The efficiency of nitrogen in cattle manures when applied to a double‐annual forage cropping system

The use of cattle manure (CM) for fertilization presents challenges for optimizing nitrogen (N) use. Our work aimed to assess N efficiencies, in a 6‐year experiment with three biennial rotations of four crops: oat–sorghum (first year) and ryegrass–maize (second year) in a rainfed humid Mediterranean area of Spain. Fertilization treatments included the following: control (no N), 250 kg mineral N ha^?1 year^?1 (250MN), three CM rates (supplying 170, 250 and 500 kg N ha^?1 year^?1) and four treatments where the two lowest CM rates were complemented with either 80 or 160 kg mineral N ha^?1 year^?1. Treatments were distributed randomly in each of three blocks. Maximum dry‐matter yield (~44–49 t ha^?1 rotation^?1) was achieved in the third rotation, and only the control and the 170CM yielded significantly less. Within the limitations of the EU Nitrate Directive, the N steady state supply of 170CM always requires a complement of mineral N (80 kg N ha^?1) to maximize N agronomic efficiency. The maximum N‐fertilizer replacement value (250CM vs. 250MN) was 0·67, without significant differences between the two treatments in other N‐related efficiency indexes, which indicates that plants took advantage of residual‐N effects. Nitrogen losses by leaching in the 250CM treatment were around 5–7% of the N applied. This reinforces the sustainability of manure recycling in long cropping seasons.     

The chemistry of humic and fulvic acids extracted from argentine soils—I. Analytical characteristics

Five humic and three fulvic acids were extracted from Argentine Chestnut, Brunizem, Solod and Solonetz soils and analysed by electrometric, spectroscopic and spectrometric methods. There were great similarities in elementary analysis, functional group content, absorption characteristics in the visible region and in the IR, and in the ESR measurements between the humic acids and, similarly, between the fulvic acids. There were distinct differences between the humic and fulvic acids in C, H, N and O content, distribution of oxygen in functional groups, E₄/E₆ ratios and free radical content.     

Effectiveness of Twenty-Four Barley Resistance Genes Against Powdery Mildew (Erysiphe graminis DC f. sp. hordei Em. Marchal) in Spain

Twenty-four near-isogenic barley lines, with a cv.‘Pallas’ background, carrying different mildew resistance genes were subjected in 1987, 1989 and 1990 to natural infection by the pathogen at several different and contrasting Spanish sites in order to study its virulence. The virulence genes proved to be geographically grouped into three regions: western (Valladolid), southern (Sevilla) and northern and northeastern (Navarra, Lleida and Girona). The mildew population of Lleida was more variable when compared with Navarra and Valladolid. Overall, the most effective resistance genes were: Ml-a13 + Ml-(Ru3), mlo and Ml-(1402).     

The role of small reserves in plant conservation in a region of high diversity in eastern Spain

The Valencian region, in eastern Spain, is home to ≈3050 vascular plant species, 68 of which are listed under the critically endangered IUCN category. To afford protection to our endangered, rare and endemic flora, a network of small (2-20 ha) statutory reserves has been created by the Regional Wildlife Service. These are termed “micro-reserves” and encompass a large number of individual species and natural habitats. The objective is to monitor long term changes in the plant populations and to carry out active management of the protected plants. In the selection of plots, criteria of distinctiveness and endangerment of plants was followed. Eight years after the onset of this initiative, plant micro-reserves have become an essential tool for the effective protection of the diverse flora of this Mediterranean region.     

Experimental use of polyamide bands in combination with intramedullary pinning for repair of oblique femoral fractures in rabbits

OBJECTIVE: To evaluate the use of polyamide bands, manufactured for securing electrical cables, for repair of oblique femoral fractures in rabbits. STUDY DESIGN: Experimental study. ANIMALS: Twelve nulliparous, 21-25-week-old, California female rabbits. METHODS: Rabbits were divided into 3 groups (n=4) and studied for 14, 28, or 56 days. A Z-shaped mid-diaphyseal femoral osteotomy was repaired with a 2.5 mm intramedullary pin and a polyamide 6.6 cerclage band. Healing was evaluated at intervals by physical examination, limb use, femoral radiographs, and callus histology. RESULTS: Rabbits had early limb use with good wound healing. From the 1st day, movement of the hip and stifle joints was satisfactory. Radiographically, fractures were healed at 28 days. Histologically, there was no foreign body reaction and bone healing was normal. CONCLUSION: Nylon cerclage band application was accomplished easily, maintained reduction, and resulted in good healing and limb use. CLINICAL RELEVANCE: Sterilized nylon bands, manufactured for electrical use, can be used for cerclage in rabbits.     

Retrospective study of the prevalence of postanaesthetic hypothermia in cats

A retrospective study of 275 anaesthetic records of cats was undertaken to examine the prevalence of postanaesthetic hypothermia, its clinical predictors and consequences. Temperature was recorded throughout anaesthesia. The temperature reached at the end was classified as hyperthermia (>39.50 °C), normothermia (38.50 to 39.50 °C), slight hypothermia (38.49 to 36.50 °C), moderate hypothermia (36.49 to 34.00 °C) or severe hypothermia (<34.00 °C). Statistical analysis consisted of multiple regression to identify the factors that affect the temperature at the end of the procedure. Before premedication, the mean (sd) temperature was 38.2 (1.0) °C. At 60, 120 and 180 minutes from induction, the temperature was 35.4 (1.4) °C, 35.0 (1.5) °C and 34.6 (1.5) °C, respectively. The prevalence of hypothermia was slight 26.5 per cent (95 per cent CI 21.7 to 32.0 per cent), moderate 60.4 per cent (95 per cent CI 54.5 to 66.0 per cent) and severe 10.5 per cent (95 per cent CI 7.4 to 14.7 per cent). The variables associated with a decrease in the temperature recorded at the end of anaesthesia were the duration of anaesthesia, the reason for anaesthesia (abdominal and orthopaedic surgeries significantly reduced the temperature when compared with minor procedures) and the anaesthetic risk (high-risk cats showed lower temperatures than low-risk cats). The temperature before premedication was associated with an increase in the final temperature.