Plasma pentachlorophenol concentrations in calves exposed to treated wood in the environment

Six calves were fed grain and hay from a pentachlorophenol (PCP)-treated feeder twice daily. Samples of blood were collected twice a week. Plasma PCP concentrations increased rapidly to a maximum of 1,086 microgram/L within 10 days. After the 3rd week, calves were denied access to the treated feeder; PCP values returned rapidly to near base line (before calves were fed from the treated feeder). After base-line plasma PCP values were reached, 4 of the 6 calves were housed in a total confinement building and exposed (by inhalation) to lumber that was commercially treated with PCP. The building itself was free of structural PCP-treated lumber. The ratio of building volume to treated wood surface was approximately 49 to 1. During the 3 weeks the calves were confined, PCP values did not increase and were markedly lower than those associated with oral exposure to treated wood. Oral dosing of calves with PCP in capsules--0.05 and 0.5 mg/kg--resulted in maximal plasma PCP values of 1,449 and 9,555 micrograms/L, respectively. Oral exposures (feeding from contaminated feeder; capsule) appeared to be more important than inhalation in causing increased plasma PCP concentrations in cattle. Exposure from these sources may be estimated by comparison with experimental values from dose-response studies. Feeding from treated feeders resulted in lower plasma PCP values than did dosing with 0.05 mg/kg daily.     

Definition of animal breeding goals for sustainable production systems

What we do is determined by the way we "view" a complex issue and what sample of issues or events we choose to deal with. In this paper, a model based on a communal, cultural, or people-centered worldview, informed by a subjective epistemology and a holistic ontology, is considered. Definitions and interpretations of sustainable agriculture are reviewed. Common elements in published definitions of sustainable agriculture and animal production among those who seek long-term and equitable solutions for food production are resource efficiency, profitability, productivity, environmental soundness, biodiversity, social viability, and ethical aspects. Possible characteristics of future sustainable production systems and further development are presented. The impact of these characteristics on animal breeding goals is reviewed. The need for long-term biologically, ecologically, and sociologically sound breeding goals is emphasized, because animal breeding determined only by short-term market forces leads to unwanted side effects. Hence, a procedure for defining animal breeding goals with ethical priorities and weighing of market and non-market values is suggested. Implementation of non-market as well as market economic trait values in the aggregate genotype, as suggested, may allow for breeding programs that contribute to sustainable production systems. Examples of breeding goals in salmon, cattle, and pigs are given, and the resulting genetic responses are evaluated with respect to economic profit (or costs) and other criteria of sustainability. Important prerequisites for breeding programs for sustainable production are appropriate governmental policies, awareness of our way of thinking, and a more communal worldview informed by a subjective epistemology and a holistic ontology.     

Self-Fertile Doubled Haploid Plants of Perennial Ryegrass (Lolium perenne L.)

The self-fertility of chromosome-doubled haploid lines of perennial ryegrass and their first (I₁) and second (I₂) generation selfed offspring was studied. The overall seed set was low, 0—0.4 seeds per spike, as would be expected for chromosome-doubled haploids of a self-incompatible species. Nevertheless, significant genetic variation was observed for self-fertility within three of the six lines studied. Within one line, three I₂-clones showed increased self-fertility, while in two other lines one and three I₁-clones, respectively, showed significantly increased self-fertility. Selection, during selfing, of rare pollen grains with mutations in the self-incompatibility system could explain the observed changes and would lead to a general breakdown of self-incompatibility in Lolium perenne during repeated selfing of chromosome-doubled haploids.     

A technical solution to the mass-culturing of larval turbot

A 1000 litre recirculation system of eight cylindrical rearing tanks has been tested in three 40-day periods to determine its capacity for rearing larval turbot (Scophthalmus maximus L.).The larvae were fed on rotifers and Artemia nauplii, as well as mixed marine algae. Continuous artificial light of 1500–2000 lux was applied at the surface. The applied algae served a dual function; keeping rotifers and Artemia at a high nutritional level as well as effectively removing the released ammonia. The combination of upwelling water and light at the surface maximized the contact surface between larvae, food items and algae.With this system, using a stocking density of 16 larvae litre^?1 in the rearing tanks, a survival total of 40% at Day 40 was achieved, giving a production of 6·4 larvae litre^?1 or 3000 larvae metre^?2 of the surface of the rearing tanks.     

Prevalence of Anaplasma phagocytophilum infection and effect on lamb growth

Background

A major challenge in sheep farming during the grazing season along the coast of south-western Norway is tick-borne fever (TBF) caused by the bacteria Anaplasma phagocytophilum that is transmitted by the tick Ixodes ricinus.

Methods

A study was carried out in 2007 and 2008 to examine the prevalence of A. phagocytophilum infection and effect on weaning weight in lambs. The study included 1208 lambs from farms in Sunndal Ram Circle in Møre and Romsdal County in Mid-Norway, where ticks are frequently observed. All lambs were blood sampled and serum was analyzed by an indirect fluorescent antibody assay (IFA) to determine an antibody status (positive or negative) to A. phagocytophilum infection. Weight and weight gain and possible effect of infection were analyzed using ANOVA and the MIXED procedure in SAS.

Results

The overall prevalence of infection with A. phagocytophilum was 55%. A lower weaning weight of 3% (1.34 kg, p < 0.01) was estimated in lambs seropositive to an A. phagocytophilum infection compared to seronegative lambs at an average age of 137 days.

Conclusions

The results show that A. phagocytophilum infection has an effect on lamb weight gain. The study also support previous findings that A. phagocytophilum infection is widespread in areas where ticks are prevalent, even in flocks treated prophylactic with acaricides.     

Impacts and adaptation of European crop production systems to climate change

The studies on anthropogenic climate change performed in the last decade over Europe show consistent projections of increases in temperature and different patterns of precipitation with widespread increases in northern Europe and decreases over parts of southern and eastern Europe. In many countries and in recent years there is a tendency towards cereal grain yield stagnation and increased yield variability. Some of these trends may have been influenced by the recent climatic changes over Europe.A set of qualitative and quantitative questionnaires on perceived risks and foreseen impacts of climate and climate change on agriculture in Europe was distributed to agro-climatic and agronomy experts in 26 countries. Europe was divided into 13 Environmental Zones (EZ). In total, we had 50 individual responses for specific EZ. The questionnaires provided both country and EZ specific information on the: (1) main vulnerabilities of crops and cropping systems under present climate; (2) estimates of climate change impacts on the production of nine selected crops; (3) possible adaptation options as well as (4) adaptation observed so far. In addition we focused on the overall awareness and presence of warning and decision support systems with relevance for adaptation to climate change.The results show that farmers across Europe are currently adapting to climate change, in particular in terms of changing timing of cultivation and selecting other crop species and cultivars. The responses in the questionnaires show a surprisingly high proportion of negative expectations concerning the impacts of climate change on crops and crop production throughout Europe, even in the cool temperate northern European countries.The expected impacts, both positive and negative, are just as large in northern Europe as in the Mediterranean countries, and this is largely linked with the possibilities for effective adaptation to maintain current yields. The most negative effects were found for the continental climate in the Pannonian zone, which includes Hungary, Serbia, Bulgaria and Romania. This region will suffer from increased incidents of heat waves and droughts without possibilities for effectively shifting crop cultivation to other parts of the years. A wide range of adaptation options exists in most European regions to mitigate many of the negative impacts of climate change on crop production in Europe. However, considering all effects of climate change and possibilties for adaptation, impacts are still mostly negative in wide regions across Europe.     

Nursing sickness in lactating mink (Mustela vison). II. Pathophysiology and changes in body fluid composition.

An investigation of the pathophysiological characteristics of nursing sickness in mink was carried out as a follow-up study of a previous epidemiological survey at a Danish fur research farm during the 1989 breeding season. In a total of 48 nursing females of the Standard Black and Pastel type, concentrations of several pertinent biochemical constituents of whole blood, plasma, urine and skeletal muscle were determined in order to identify nutritional and metabolic factors involved in the origin and development of the disease. Compared to the reference data obtained in 17 apparently normal lactating dams the findings in 31 females suffering from nursing sickness presented varying clinical and biochemical signs of progressive dehydration and emaciation: aldosteronism, hypovolemia, hyponatremia, hyperkalemia (in the face of muscle potassium depletion), hyperglycemia and azotemic acidemia. Neither ketosis nor severe lactacidemia was observed. The urine was almost devoid of sodium and chloride, and urinary potassium concentration diminished by approximately 50%. The concentrating ability of the kidneys was reduced to less than one third of the maximum value. The results were consistent with severe dehydration and emaciation due to heavy losses of energy, water and body mass along with increasing milk production. The progressive nature of the disease supported the hypothesis that nursing sickness is due to the combined effects of heavy milk production and excessive tissue catabolism along with reduced or ceased dietary intake, and maybe increasing environmental stress. In the advanced stage of the disease coma and death appear to be the inevitable outcome of the metabolic strains for continuing milk production.     

Nitrogen cycling in organic farming systems with rotational grass–clover and arable crops

Organic farming is considered an effective means of reducing nitrogen losses compared with more intensive conventional farming systems. However, under certain conditions, organic farming may also be susceptible to large nitrogen (N) losses. This is especially the case for organic dairy farms on sandy soils that use grazed grass–clover in rotation with cereals. A study was conducted on two commercial organic farms on sand and loamy sand soils in Denmark. On each farm, a 3‐year‐old grass–clover field was selected. Half of the field was ploughed the first year and the other half was ploughed the following year. Spring barley (Hordeum vulgare L.) was sown after ploughing in spring. Measurements showed moderate N leaching during the pasture period (9–64 kg N ha^?1 year^?1) but large amounts of leaching in the first (63–216 kg N ha^?1) and second (61–235 kg N ha^?1) year after ploughing. There was a small yield response to manure application on the sandy soil in both the first and second year after ploughing. To investigate the underlying processes affecting the residual effects of pasture and N leaching, the dynamic whole farm model farm assessment tool (FASSET) was used to simulate the treatments on both farms. The simulations agreed with the observed barley N‐uptake. However, for the sandy soil, the simulation of nitrate leaching and mineral nitrogen in the soil deviated considerably from the measurements. Three scenarios with changes in model parameters were constructed to investigate this discrepancy. These scenarios suggested that the organic matter turnover model should include an intermediate pool with a half‐life of about 2–3 years. There might also be a need to include effects of soil disturbance (tillage) on the soil organic matter turnover.     

Distribution of Feline Blood Types Detected in the Copenhagen Area of Denmark

Jensen, A. L., A. B. Olesen and J. Arnbjerg: Distribution of feline blood types detected in the Copenhagen area of Denmark. Acta vet. scand., 1994, 35, 121-124.–The purpose of the present study was to make the first survey of the distribution of feline AB blood types in the Copenhagen area of Denmark. A total of 244 cats (139 purebred cats and 105 Domestic Shorthair cats) were tested. 93% of all tested cats had blood type A. Neither an AB nor an O type cat was detected and thus, the frequency of blood type B among all tested cats was 7%. Most type B cats were purebred cats (Birman, British Shorthair and Persian cats). No association between sex and blood type could be demonstrated among British Shorthair and Persian cats. Thus, the present study indicates that cats in Denmark predominantly have blood type A, and that blood type B cats are rare, except for certain breeds such as Birman and British Shorthair cats.     

Fungicide treatments affect yield and moisture content of grain and straw in winter wheat

Straw and grain yield and water content in both grain and straw were measured during 3 years in 17 varieties of winter wheat following treatments with different fungicides. The water content of the straw varied significantly dependent on year, variety and fungicide treatment. In 1998, the water content in straw was significantly higher after the use of strobilurins compared with untreated and EBI fungicides (ergosterol biosyntesis inhibitors). On average water content in 10 varieties increased from 15% in untreated to 31% after applying two full dosages of azoxystrobin. In 1999 and 2000, lower dosages of azoxystrobin were used and water content increased only by 2–4 percentage units. The results indicate that in some years and with high doses precaution has to be taken following the use of strobilurins regarding handling and removing of the straw, which likely will include postponement of baling. Water content in grain was also increased significantly from fungicide treatments, but the increase was minor and at the maximum increase found to be 1.1% percentage unit. The effect of fungicide input on water content in grain was reduced much faster during the ripening period than for water content in straw. Fungicide treatments and varieties significantly influenced straw yields. The yield increases in straw varied between 0 and 1.0 tonnes/ha depending on year and variety, and was on average 0.42 tonnes/ha for two fungicide treatments. Two fungicide applications carried out at GS 31 and 45–55 gave only slightly higher increases compared with one application around ear emergence. Varieties showed variable increases following the use of fungicides. The variation was not influenced by the straw length (crop height). The increases in straw yield from fungicide treatments were relatively low compared to the increases in grain yield and no clear correlation was found between grain yield increases and straw yield increases.