Temperature‐dependent feed requirements in farmed blue mussels (Mytilus edulis L.) estimated from soft tissue growth and oxygen consumption and ammonia‐N excretion

Feed requirements were estimated from specific growth rates in standardized soft tissue dry weight (SGR_DW’) and atomic O:N ratios for mussels fed seven rations of microalgae (5–735 μg C h^?1 ind^?1) at 7 and 14°C respectively. The mean oxygen consumption and ammonia‐N excretion rates were significantly higher at 14°C (0.29 μg O² and 27.3 μg N ind^?1 h¹) compared with those at 7°C (0.16 μg O² and 11.4 μg N ind^?1 h^?1) (P < 0.05), resulting in O:N ratios between 3 and 45 at 7°C and 7 and 28 at 14°C. Low O:N ratios indicate protein catabolism and an unfavourable condition, whereas high ratios indicate that carbohydrate is the primary energy source. The measured SGR_DW’ suggests minimum feed requirements of ~240 and ~570 μg C ind^?1 h^?1 for weight maintenance at 7 and 14°C, with corresponding O:N ratios of 24 and 16, respectively, indicating a more stressed condition at 14°C. A 0.5% SGR_DW’ day^?1 was obtained by ~565 (O:N = 29) and ~680 (O:N = 23) μg C ind^?1 h^?1 at 7 and 14°C respectively. A positive and significantly higher SGR_DW’, with the lowest feed ration at 7°C compared with a negative SGR_DW’ at 14°C (P < 0.05), indicated that storage time can also possibly be prolonged at low temperatures if the mussels are not fed.     

Tolerability and pharmacokinetic profile of a novel benzene‐poly‐carboxylic acids complex with cis‐diammineplatinum (II) dichloride in dogs with malignant mammary tumours

The pharmacokinetic profile, tolerability and efficacy of benzene‐poly‐carboxylic acids complex with cis‐diammineplatinum (II) dichloride (BP‐C1) were studied in dogs with mammary cancer. A three‐level response surface pathway designed trial was performed on seven dogs. At each level BP‐C1 was administered subcutaneously daily for 7 days followed by a 7‐day rest period in a dose escalating manner. Adverse events according to VCOG‐CTCAE, performance status and tumour progression were recorded. The pharmacokinetic profile followed a two‐compartment model with rapid absorption, short distribution, and a slow elimination phase. The overall elimination half‐life was 125 h. The maximum tolerated dose of BP‐C1 was estimated to be above 0.46 mg kg^?1. A significant reduction in VCOG‐CTCAE toxicity which correlated negatively with increasing dose was found. The dogs' general performance status remained unchanged. No decrease in total tumour burden was found, although temporary tumour reduction was seen in some target tumours.     

Open geospatial technology standards and their potential in plant pest risk management—GPS-enabled mobile phones utilising open geospatial technology standards Web Feature Service Transactions support the fighting of fire blight in Norway

The threat posed by invasive alien species to global crop production and biodiversity is recognized as one of the major drivers of global change today. Here we report on a successful implementation and operational use of new technology to support risk- and crisis management in the case of fighting an invasive plant disease. The open geospatial standards Web Feature Service Transaction (WFS-T) was implemented in software for GPS-enabled mobile phones communicating with a GeoServer backend in order to track down and eradicate disease outbreaks and susceptible host plants. This new technology offering georeferenced events online from field provides new possibilities for real time action in risk and crisis management.     

Soil fertility in three cropping systems after conversion from conventional to organic farming

Abstract

Temporal changes in the scores of selected soil fertility indices were studied over six years in three different cases of organic crop rotation located in southern, eastern and central Norway. The cropping history and the initial scores of fertility indices prior to conversion to organic cropping differed between the sites. Crop yields, regarded as an overall, integrating fertility indicator, were in all rotations highly variable with few consistent temporal trends following the first year after conversion. On the site in eastern Norway, where conversion followed several years of all-arable crop rotations, earthworm number and biomass and soil physical properties improved, whereas the system was apparently degrading with regard to P and K trade balances and contents in soil. On the other two sites, the picture was less clear. On the southern site, which had a relatively fertile soil before conversion, the contents of soil organic matter and K decreased during the six-year period, but the scores of other fertility indices showed no trends. On the site in central Norway, there were positive trends for earthworm-related indices such as worm biomass and tubular biopores, and negative trends for soil porosity. The results, especially those from the eastern site, illustrate the general difficulty in drawing conclusions about overall fertility or sustainability when partial indicators show divergent trends. Consequently, the study gave no unambiguous support to the initial working hypothesis that organic farming increases inherent overall soil fertility, but rather showed that the effect varied among indicators and depended on status of the cases at conversion. It is concluded that indicators are probably better used as tools to learn about and improve system components than as absolute measures of sustainability.     

Effects of defoliation on carbohydrate status,nodules and spring growth in white clover in a sub-arctic climate

Abstract

In order to improve the basis for utilizing white clover (Trifolium repens L) in northern agriculture, we studied the effects of defoliation intensity on spring growth in a sub-arctic climate in relation to carbohydrate and nodule status. White clover plants (cv Snowy) were studied in a pot experiment in the field on the coast of northern Norway from spring 2001 until spring 2002. The experiment was repeated with some modifications from spring 2002 until spring 2003. During the growing season from summer to autumn, the plants were totally stripped of leaves down to the stolon, cut at four or seven cm height or left undisturbed. The plants were sampled destructively in autumn, early spring and late spring and sorted into leaves, stolons and roots. The plant material was weighed and analysed for carbohydrate reserves and nodule number. Defoliation during the growing season resulted in reduced concentration of reserve carbohydrates in autumn and reduced winter survival of the stolons. The most severe defoliation treatment reduced the herbage growth in spring. In contrast, the two milder defoliation treatments had no effect on herbage growth during spring or on total plant dry matter and nodule status in late spring. In conclusion, moderate defoliation during the growing season had no effect on herbage growth the following spring nor on carbohydrate, nodule or dry matter status of the plant in late spring. Moderate defoliation increased spring growth and thereby also the nitrogen demand of the plants. This probably enhanced nodule formation and development of inactive to active nodules.     

Developing and testing prognostic bio‐scoring systems for canine mammary gland carcinomas

Canine mammary carcinomas (CMC) represent a range of histolopathological subtypes with diverse biological behaviours. Several individual factors, including stage, grade, subtypes and presence of invasion, predict outcome. Less is known how these factors interact and impact prognosis. The purpose of this work was to develop and test comprehensive bio‐scoring systems in CMCs. Clinical and histopathological data from 127 dogs with MCs treated through two prospective studies were obtained. All dogs underwent standardized pre‐surgical staging, treatments and regular follow‐up visits. All tumours were evaluated, classified and graded according to published guidelines. Time to primary metastasis was the main endpoint in this study. Two bio‐scoring systems were developed: The multivariate scoring (MVS) was based on traditional statistical analysis where only factors significant in the multivariate analysis (tumour size and grade) were kept for the final model. The refined flexible scoring (RFS) system was based on results from subgroup analysis, which guided the development of a flexible system. Progressive worsening prognosis was observed with increasing bio‐scores in both systems. MVS: Median primary metastasis‐free survival (TTM1 days) was not reached in dogs with bio‐scores 0 to 5, 10, 15 and 648, 149, 317, in MVS groups 25, 30, 40, respectively. Similarly, TTM1 was not reached in dogs with RFS 0, 1, 2 and 374, 407 and 149, in dogs with bio‐scores 3, 4, 5, respectively. However, a more distinct separation between dogs with high risk vs low risk for metastasis was observed with RFS, suggesting superior overall prognostication regarding the risk for metastasis.     

Absorption from water as an alternative method for the administration of sulphonamides to rainbow trout, salmo gairdneri. The significance of the pKa value of the sulphonamides and the pH and salt content of the water.

The effect of variations in pH and salt concentration on the absorption by rainbow trout of sulphonamides from water was investigated. Two trials were carried out: 1) Absorption from fresh water of sulphanilamide (pKa 10.4) and sulphadimidine (pKa 7.4) at pH 4, 6, 8 and 10 over a period of 96 hrs., and 2) Absorption from fresh water and sea water (salinity approx. 31 ‰) of the same two sulphonamides at pH 6 and 8 over a period of 24 hrs. The degree of acetylation of the two sulphonamides in rainbow trout was investigated.     

Mixtures of crushed rock, forest soils, and sewage sludge used as soils for grassed green areas

In two container experiments, we evaluated mixtures of crushed rock, forest soil, and sewage sludge for use as growth media in green areas. We applied two types of crushed rock (0–2 mm fraction), two forest soils (sandy loam), and limed sewage sludge (pH 10), and studied the growth of ryegrass (Lolium multiflorum var. westervoldicum) during one growing season.Including ≥0.2 m³ m⁻³ sewage sludge in the soil mixtures initially inhibited growth, presumably due to toxic levels of ammonium-N. Up to 0.25 m³ m⁻³ sludge increased the total yield of ryegrass, but at a level as low as 0.1 m³ m⁻³, more nutrients were available than could be taken up by the crop. At present, up to 0.3 m³ m⁻³ sewage sludge is allowed in soil mixtures used in green areas in Norway, although that level should probably be lowered due to the risk of abnormal (enhanced or inhibited) plant growth, and leaching of nutrients. We recommend a maximum of 0.1 m³ m⁻³ when applying the kind of sludge used in our experiments.All mixtures containing acid forest soil gave better results than those comprising slightly alkaline forest soil. The best mixture for ryegrass was crushed rock and acid forest soil at a ratio of 1:2. Compared to pure acid forest soil ryegrass grew equally well or better on mixtures containing ≥0.50 m³ m⁻³ acid forest soil. The differences in growth between the various soil mixtures were due to texture and physical properties, and to dissimilarities in the effects of sewage sludge on mineralisation of nitrogen in the mixtures comprising acid and slightly alkaline forest soil.     

Impact of milking characteristics and morphology of udder and teats on clinical mastitis in first- and second-lactation Norwegian cattle

Data from the Norwegian progeny testing program were used to examine the impact of milking characteristics and morphology of udder and teats on clinical mastitis in first- and second-lactation Norwegian cattle. The study was designed as a 1-1 matched case-control study with herd, parity, days in lactation and calving season as matching variables. Conditional maximum likelihood logistic regression was used to evaluate the effects of three primary (2 min milk, milk leakage and teat-end-to-floor distance) and six other study variables. Treatment records from the Norwegian health card system on acute and chronic clinical mastitis were used to define cases. The chosen model included 565 matched pairs. Significant risk factors of clinical mastitis were decreasing teat-end-to-floor distance (P = 0.02) and periparturient udder edema (P < 0.01).

Borderline effects were demonstrated by larger than herd-average teat diameter (P = 0.04), udder asymmetry (P = 0.05) and increasing 2 min milk (P = 0.08). Results were compared to a previous study on the same data with log_e somatic cell count as the dependent variable. Inclusion of teat-end-to-floor distance in the genetic improvement scheme may increase the efficiency of genetic selection for mastitis resistance.