Transthoracic echocardiographic measurement of patent ductus arteriosus in dogs

BACKGROUND: Patent ductus arteriosus (PDA) size and morphology influence the selection of the kind and the size of the embolization device used to effect shunt closure. HYPOTHESIS: That echocardiographic measurement of PDA in dogs is accurate. ANIMALS: Forty-five client-owned dogs with PDA. METHODS: Prospective observational study. Echocardiographic and angiographic data were compared. RESULTS: Measurement of the ductus in color Doppler echocardiography (CD-E) and 2-dimensional echocardiography (2D-E) was achieved from left parasternal views in 43 of 45 unsedated dogs (96%). In these 43 dogs, the angiographic minimal PDA diameter was 3.72 +/- 1.59 mm, and the diameter of the PDA ampulla was 8.46 +/- 3.01 mm. The CD-E minimal PDA diameter ranged from 2.3 to 9.5 mm (median, 4.0 mm). There was a significant mean difference to the angiographic measurements (1.15 +/- 0.95 mm; P < .0001). An agreement in a 1-mm range was found in 21 of 43 dogs (48%). The 2D-E minimal PDA diameter was 3.73 +/- 1.78 mm, and the mean difference to the angiographic measurements was not significant (0.00 +/- 0.72 mm; P = .98). An agreement in a 1-mm range was found in 31 of 43 dogs (72%). The 2D-E measurement of the PDA ampulla revealed a significant mean difference to the angiographic data (1.95 +/- 2.43 mm, P < .0001). An agreement in a 2-mm range was found in 21 of 43 dogs (49%). CONCLUSIONS AND CLINICAL IMPORTANCE: The 2D-E from the left cranial parasternal view is an excellent noninvasive method to estimate the PDA minimal diameter before doing catheter intervention.     

High-resolution ultrasonography of xenografted domestic cat ovarian cortex

Transplantation of ovarian tissue has high potential for female gamete conservation. However, optimal timing of oocyte recovery for in vitro maturation and fertilization is still critical. Therefore the aim of the present study was to use high-resolution transcutaneous ultrasonography to monitor follicular development within xenografted ovarian tissue. Ovarian cortex fragments (n=44) from domestic cats were transplanted into athymic nude rats (n=12). Graft development in the animals was assessed weekly by high frequency ultrasound (10-22 MHz) under two different FSH regimes. Blood collection for serum estradiol determination and vaginal smears were performed simultaneously. The xenografts were removed at different time points according to the ultrasound findings. The survival rate of the transplants 4 weeks after surgery was 54.5% and antral follicular growth was observed within 10 grafts from 5 different hosts (8.6 +/- 6.43 follicles per graft). Early follicle antrums could be detected from 0.4 mm onwards. The growth rate of the antral cavity was calculated from weekly measurements (0.56 +/- 0.44 mm per week). Although vaginal cells and estradiol levels followed a cyclic pattern, no correlation was found between follicular diameter, estradiol and keratinized vaginal cells. We recovered 5, 1 and 4 cumulus oocyte complexes from three different individuals during weeks 19, 21, and 23 respectively. Extrusion of a polar body (1 oocyte) and germinal vesicle break down (7 oocytes) indicated progression of maturation after in vitro culture. We conclude that ultrasonography und provided a reliable method to examine xenograft survival and follicular development within the grafts. Furthermore, this technique is suitable for assessment of the efficiency of hormonal treatment and narrowing of the optimal time frame for oocyte retrieval. To our knowledge, this is the first report of the in vivo development of early antral follicles in mammalian species.     

Seroprevalence of antibodies to Salmonella spp in semidomesticated reindeer in Norway,determined by enzyme-linked immunosorbent assay

An indirect ELISA was developed as a possible tool to detect the seroprevalence of antibodies to Salmonella spp in semidomesticated reindeer. To cover a broad spectrum of serogroups a lipopolysaccharide mix of S. typhimurium and S. choleraesuis was used as antigen in this pilot study. Sera from 31 culture-negative reindeer with no clinical or historical evidence of salmonellosis were used as negative serum control. After immunisation with an inactivated S. typhimurium vaccine, pooled sera from 6 reindeer were used as positive serum control as no serum from naturally infected animals was available. A seroprevalence of 0.6% in 2000 clinically healthy, slaughter-reindeer from Norway was determined by using this ELISA. No more information on Salmonella in reindeer in Norway is known to the authors. This is the first ELISA established for indirect detection of Salmonella in reindeer.     

Results of the German investigation on the EU project "Salmonella in Pork (Salinpork)"--1. Investigations in the farms

Reports of human salmonellosis caused by the consumption of pork and the introduction of control and surveillance programmes in different countries of the European Union were the reason for carrying out an international study under the title "Salmonella in Pork (Salinpork)": Six different EU-countries were involved in this study, which was supported by the Commission of the European Community and which was carried out over a period of April 1996 to April 1999. The aim of the investigation presented was to determine the prevalence of Salmonella in fattening, breeding and farrow-to-feeder herds as well as the determination of risk factors for the introduction of Salmonella into the farm (Part 1). In addition, sources of contamination of pork should be detected by taking samples of the product and the environment in the slaughterhouse (Part 2). In Germany, the investigation into Salmonella infections of 60 fattening, 20 breeding and 20 farrow-to-feeder herds were carried out in Schleswig-Holstein. The investigation included bacteriological examinations of feed and faecal samples for sero- and phagetyping and serological examinations by using the Danish Mix-ELISA. From 2,947 serological investigated fattening pigs were 7.3% (n = 213) positive, from 797 breeding sows 9.2% (n = 73) were serological positive and 4.5% (n = 18) of the investigated sows (N = 399) in farrow-to-feeder herds were serological positive. Altogether, 28.3% of the fattening, 50.0% of the breeding and 15.0% of the farrow-to-feeder herds were serological positive. A questionnaire was used to capture data about management, hygiene measures, feeding systems and the occurrence of diseases in the herd. After statistical analysis the common risk factor of fattening herds and sow herds was the use of pelleted feed. But in a control study with 17 different fattening herds the result could not be proven. Other factors which can influence the occurrence of Salmonella infections were discussed.     

Results of the German investigation in the EU Project "Salmonella in Pork (Salinpork)"--2. Investigations in a slaughterhouse

In 1997 bacteriological examinations for the distribution of Salmonella in slaughterhouses were carried out in Germany within the framework of an international study "Salmonella in Pork (Salinpork)". During 6 days, 1,200 swab and water samples from slaughtered pigs and the environment were taken. 4.4% of the samples (n = 53) were Salmonella positive. S. typhimurium was isolated mainly (69.8%; n = 37), and 6 phagetypes were differentiated. In addition, S. derby and S. panama could be demonstrated. The resistance pattern of the different isolated S. typhimurium-phagetypes are presented. The phagetype DT 104 was multiresistant to ampicillin, spectinomycin, streptomycin, sulphonamide and tetracycline. In comparison with the serological prevalence of 7.3% of the fattening pigs in the farms (Part 1), only 1.0% of the samples taken from the surface of the carcass were Salmonella-positive. Swabs taken from the liver were in 2.7% positive and samples from the tongue gave in 5.3% of the cases Salmonella-positive results. In the examination of the environment Salmonella was demonstrated mainly from the water outlets, whereas Salmonella could not be isolated from water of the scalding tank. There was only one case (0.7%) in which Salmonella could be isolated from the hands of the personnel, and also only one swab of the polishing machine was positive (1.1%). But 6.7% samples of the saw were Salmonella-positive. A comparison of repeated, at intervals taken samples showed that the number of Salmonella-positive samples was higher in the last examination round of the particular slaughter days. The reason is suspected in the increasing number of slaughtered pigs and supplying farms, which may increase the probability of bringing in Salmonella.     

Prevalence of Salmonella in Ethiopian cattle and minced beef

To estimate the prevalence and distribution of Salmonella in the chain from cattle to the consumer, faeces, mesenteric lymphnodes and beef cuts from 235 cattle, stool samples from 300 workers of the same Addis Ababa abattoir, and 330 minced beef samples from supermarkets in Addis Ababa were analyzed. Isolated Salmonella strains were serotyped and tested for antibiotic susceptibility. Low prevalence in faeces and lymphnodes, and higher contamination rates of beef cuts (diaphragm, abdominal muscles) indicate severe cross-contamination during slaughter. Animals of poor health status were far more frequently carriers of salmonellae, which stresses the need of intensive ante-mortem inspection on slaughter animals. During transport from slaughterhouse to the supermarkets, production and selling of minced beef, the prevalence of Salmonella did not increase.     

Application of an enzyme-immunoassay (EIA) for rapid screening of 5 alpha-pregnane-3,20-dione (DHP) in blood plasma of the Asian elephant, Elephas maximus.

Populations of African (Loxodonta Africana) and Asian Elephants (Elephas maximus) in zoos and safari parks are at risk due to their low reproductive success. To extend the limited knowledge of their reproductive physiology, the development of easy and practical methods for the analysis of the relevant reproductive hormones is essential to support e.g. assisted reproduction. For the measurement of 5 alpha-pregnane-3,20-dione (DHP), the predominant ovarian gestagen in both species, an enzyme-immunoassay (EIA) based on commercial reagents was applied. Advantages of this EIA are the small volume of plasma needed for evaluation (5 microliters) and the possibility of direct processing without an extraction stage. The lower limit of detection was 0.16 ng/ml, the mean recovery was 101% and the mean coefficients of variation were 7.3% (intra-assay) and 9.9% (inter-assay). In Asian elephants, DHP levels reached 15 ng/ml during the luteal phase and up to 21 ng/ml during pregnancy. Estrous cycle lengths based on the lowest DHP concentrations varied from 12 to 20 weeks (mean 15.4 +/- 2.3). In two Asian elephant cows a calf was still-borne. Thereafter, the animals reassumed ovarian activity after approximately 8 and 13 weeks, respectively. In one animal estradiol implants for hormonal contraception caused a down regulation of the ovarian function as demonstrated by an irregular pattern of DHP secretion over a period of 48 weeks. We propose the direct DHP-EIA as a suitable method for reproductive monitoring in elephants, as it can be easily established in laboratories.     

A quantum laser pointer

The measurement sensitivity of the pointing direction of a laser beam is ultimately limited by the quantum nature of light. To reduce this limit, we have experimentally produced a quantum laser pointer, a beam of light whose direction is measured with a precision greater than that possible for a usual laser beam. The laser pointer is generated by combining three different beams in three orthogonal transverse modes, two of them in a squeezed-vacuum state and one in an intense coherent field. The result provides a demonstration of multichannel spatial squeezing, along with its application to the improvement of beam positioning sensitivity and, more generally, to imaging.