A preliminary report onMeriones unguiculatus as an experimental host forTaenia saginata metacestodes

Jirds (Meriones unguiculatus) were treated with dexamethasone and inoculated subcutaneously with 100–300 oncospheres ofTaenia saginata. Ten of the jirds received 0.5 mg of the drug per animal twice weekly during the first month after inoculation and then once a week until necropsy and four of these became infected. Up to 20 viable metacestodes were recovered in the subcutaneous tissue at the site of inoculation three months after infection.     

Dynamics of small biotopes in Danish agricultural landscapes

The contemporary pattern of small biotopes - small uncultivated areas in the agricultural landscape, its historical development and recent trends have been studied in Eastern Denmark. The study is based on ordinance maps dating back to 1885, aerial photographs, and field studies (1981 and 1986). The development of these areas is seen in changes in agricultural production. A general decrease in the overall density, and especially in the density of the smallest, wet biotopes, is demonstrated. This change, however, is hiding a more dynamic process of removal, establishment and change within the individual biotopes. The consequences on research, monitoring and management of the agricultural landscape are discussed.     

Fat source and calcium level effects on finishing steer performance, digestion, and metabolism

A 111-d finishing study evaluated animal growth and carcass characteristics using 138 steers (366 kg) in a randomized complete block design with a 2 x 3 factorial arrangement of treatments. The dietary treatments consisted of no supplemental fat or 3.5% tallow or soybean oil soapstock (SS) fed with .6% and .9% dietary Ca. Fat increased DMI (P less than .05) but interacted with Ca level (P less than .05) for gain/feed and ADG. All diets containing fat or .9% Ca were converted more efficiently to gain than the .6% Ca, no supplemental fat diet (P less than .05). The .9% Ca interacted with fat source to decrease gain (P less than .05) and tended to decrease efficiency in the tallow diet but improved efficiency (P less than .05) and tended to improve gain in the no-fat diet. In the SS diet, .9% Ca had no effect on ADG, DMI, or efficiency of gain. Fat addition increased backfat (P less than .10) and interacted with Ca on hot carcass weight, final weight, and dressing percentage (P less than .05). Feeding fat increased the proportion of 18:0 (P less than .02) and decreased the proportion of 16:1 fatty acids (P less than .06) in intermuscular fat. A replicated 3 x 3 Latin square design, using six Holstein steers (349 kg) fed three diets, with no supplemental fat or 3.5% SS or tallow with 1.0% Ca, was used to explore the effects of fat sources when fed with high Ca on digestion and metabolism. Ruminal fluid pH was higher (P less than .10) when steers were fed fat. Adding fat did not affect (P greater than .10) duodenal or ileal pH, VFA proportions or total concentration, or ruminal liquid volume or flow rate. Liquid retention time was shorter and liquid rate of passage was higher (P less than .05) with dietary fat addition. Adding fat did not affect site or extent of starch or DM digestion. There was net synthesis of 16:0, 18:0, and 18:1 fatty acids in the rumen. When steers were fed tallow, synthesis of 16:0 and 18:0 fatty acids in the rumen was lower (P less than .10) than when steers were fed SS. Feeding fat tended to decrease (P = .11) bacterial N flowing at the duodenum but did not affect nonbacterial N or total N. Fat addition seems to affect ruminal kinetics, and the effects may vary with fat source, particularly relative to fatty acid synthesis and digestion.     

Single-grain 40Ar-39Ar ages of glauconies: implications for the geologic time scale and global sea level variations

The mineral series glaucony supplies 40% of the absolute-age database for the geologic time scale of the last 250 million years. However, glauconies have long been suspected of giving young potassium-argon ages on bulk samples. Laser-probe argon-argon dating shows that glaucony populations comprise grains with a wide range of ages, suggesting a period of genesis several times longer ( approximately 5 million years) than previously thought. An estimate of the age of their enclosing sediments (and therefore of time scale boundaries) is given by the oldest nonrelict grains in the glaucony populations, whereas the formation times of the younger grains appear to be modulated by global sea level.     

Senior veterinary students' perceptions of using role play to learn communication skills

Recent studies of veterinary practice have suggested a correlation between well-developed communication skills and job satisfaction, career retention, customer satisfaction, decreased lawsuits, and financial remuneration for veterinarians. Veterinary educators are under growing pressure to teach functional communication skills to veterinary students; however, the methods employed have not been well evaluated. In this study we have evaluated veterinary student's attitudes to learning communication skills by participating in role play. The study indicates that experiential learning modalities such as role play are perceived as effective by students, despite reluctance to participate and some discomfort surrounding participation.     

Infectivity of Theileria parva sporozoites following cryopreservation in four suspension media and multiple refreezing: evaluation by in vitro titration

Theileria parva sporozoite stabilates are used for immunizing cattle against East Coast fever and in in vitro sporozoite neutralization assays. In this study, we attempted to identify a cheaper freezing medium and quantified the infectivity loss of sporozoites due to refreezing of stabilates, using an in vitro technique. Pools of stabilates prepared using Minimum Essential Medium (MEM), Roswell Park Memorial Institute (RPMI 1640), foetal calf serum (FCS) and phosphate-buffered saline (PBS) were compared. All were supplemented with bovine serum albumin except the FCS. RPMI 1640 was as effective as MEM in maintaining sporozoite infectivity while the infectivity in PBS and FCS reached only 59% and 67%, respectively. In a second experiment, a stabiiate based on MEM was subjected to several freeze-thaw cycles including various holding times on ice between thawing and refreezing. Refrozen stabilate gave an average sporozoite infectivity loss of 35% per cycle. The results indicate that RPMI can be used as a cheaper freezing medium for T. parva stabilates and that refrozen stabilate doses need to be adjusted for the 35% loss of infectivity.     

How landscape ecology can promote the development of sustainable landscapes in Europe: the role of the European Association for Landscape Ecology (IALE-Europe) in the twenty-first century

In Europe, landscape research has a long tradition of drawing on several disciplines. ‘National schools’ of landscape research developed, which were related to the characteristic landscapes found in the different countries and to specific linguistic meanings and legal traditions when using landscape related concepts. International co-operation demands a certain harmonization of these concepts for better mutual understanding. The 2000 European Landscape Convention provided an important momentum to rethink research, policy and management of landscapes from the perspective of sustainable development and participatory planning. Landscape ecology as a transdisciplinary science with a dynamic and holistic perspective on landscape offers a great potential for an integrative approach. The specificity of the European landscape research rests on its long history and on integration based on the great diversity of the landscapes, characterised by an intimate relationship between the varied natural environment and the different cultural traditions which define the identity of countries, regions and people. Within a unified Europe, with increasing international and trans-border co-operation and increasing common environmental problems, the creation of a specific European Association for Landscape Ecology (IALE-Europe), in addition to the existing international association and its national chapters, became justified by the need for a collaborative endeavour to address the specific problems of landscapes in Europe and to stimulate co-operation between landscape ecologists in research, education and practice.     

Ultrasonographic characteristics of soft tissue tumours in dogs

Objective   To identify and describe the ultrasonographic features of soft tissue tumours in dogs.
Procedure   Superficial soft tissue tumours of various histological types, including mast cell tumours (MCTs) and soft tissue sarcomas (STSs), were evaluated. Ultrasound was used to visualise internal characteristics of the tumour, including vascularity. Tumours were categorised according to size, shape, margin definition, tissue plane mobility, echogenicity, echotexture, acoustic shadowing or enhancement and vessel distribution. Objective measurements of intratumoural blood flow included velocities and maximal perfused cross-sectional area (fractional area). Logistic regression models incorporating a variety of data were used in an attempt to predict the histopathological type of tumours.
Results   The logistic regression model defined by the parameters echotexture, margin definition and presence of subcapsular vessels was highly predictive of MCTs (> 73%; P = 0.024). Several other trends, including a larger size for STSs and less vascularity for both MCTs and STSs, were observed, but did not reach statistical significance.
Conclusion   This preliminary study has shown the potential diagnostic value of ultrasound in differentiating soft tissue tumours. However, at present, ultrasound cannot replace biopsy and histopathological evaluation for tumour diagnosis.