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121.
J. Plendl M. Bahramsoltani O. Gemeinhardt H. Hünigen S. Käßmeyer P. Janczyk 《Anatomia, histologia, embryologia》2009,38(5):355-360
Teaching morphology, a fundamental part of medicine curricula is traditionally based on lectures and practical trainings. We introduced peer-assisted learning (PAL) and student expert teams to the courses to give the students the possibility to improve their free speech and self-confidence. We involved students in active preparation of online materials such as labelled e-slides and e-pics . We offered online digital microscopy (ZoomifyTM ) and dissection (CyberPrep) allowing repeating the learned material and studying veterinary morphology outside the dissection theatre. Over 60% of first and third semester students profited from being a peer or being taught by a peer and 50% said the expert teams were an excellent method to learn the topographic anatomy. Almost all students applied ZoomifyTM and CyberPrep and 75% of them found the digital microscopy and dissection to be a helpful or very helpful learning tool. In face of reduced contact hours, these forms of education compensated in part the lost teaching time. We observed improvement of rhetoric and presentation skills and self-confidence. The approaches should therefore find their constant place in the veterinary medicine curricula. 相似文献
122.
Carcass measurements for weight, longissimus muscle area, 12-13th-rib fat thickness, and marbling score, as well as for live animal measurements of weight at the time of ultrasound, ultrasound longissimus muscle area, ultrasound 12-13th-rib fat thickness, and ultrasound-predicted percentage ether extract were taken on 2,855 Angus steers. The average ages for steers at the time of ultrasound and at slaughter were 391 and 443 d, respectively. Genetic and environmental parameters were estimated for all eight traits in a multivariate animal model. In addition to a random animal effect, the model included a fixed effect for contemporary group and a covariate for measurement age. Heritabilities for carcass weight, carcass longissimus muscle area, carcass fat thickness, carcass marbling score, ultrasound weight, ultrasound longissimus muscle area, ultrasound fat thickness, and ultrasound-predicted percentage ether extract were 0.48, 0.45, 0.35, 0.42, 0.55, 0.29, 0.39, and 0.51, respectively. Genetic correlations between carcass and ultrasound longissimus muscle area, carcass and ultrasound fat thickness, carcass marbling score and ultrasound-predicted percentage ether extract, and carcass and ultrasound weight were 0.69, 0.82, 0.90, and 0.96, respectively. Additional estimates were derived from a six-trait multivariate animal model, which included all traits except those pertaining to weight. This model included a random animal effect, a fixed effect for contemporary group, as well as covariates for both measurement age and weight. Heritabilities for carcass longissimus muscle area, carcass fat thickness, carcass marbling score, ultrasound longissimus muscle area, ultrasound fat thickness, and ultrasound-predicted percentage ether extract were 0.36, 0.39, 0.40, 0.17, 0.38, and 0.49, respectively. Genetic correlations between carcass and ultrasound longissimus muscle area, carcass and ultrasound fat thickness, and carcass marbling and ultrasound-predicted percentage ether extract were 0.58, 0.86, and 0.94, respectively. The high, positive genetic correlations between carcass and the corresponding real-time ultrasound traits indicate that real-time ultrasound imaging is an alternative to carcass data collection in carcass progeny testing programs. 相似文献
123.
Balemba OB Hay-Schmidt A Assey RJ Kahwa CK Semuguruka WD Dantzer V 《Anatomia, histologia, embryologia》2002,31(4):237-246
In order to elucidate the organization of the enteric nervous system in the mucous plexus, wholemounts from six intestinal regions in six pigs were studied by vasoactive intestinal peptide, substance P, nitric oxide synthase and neurofilament proteins immunohistochemistry. The mucous plexus of both large and small intestine contained ganglia and isolated neurons. They were many and comparably larger in the caecum and colon, few in the ileum, and fewer and smaller in the jejunum. The mucous plexus was subdivided into the lamina muscularis mucosae and lamina proprial subplexuses, and based on location the latter was subdivided further in order to clarify their variations with respect to the amount, sizes and shapes of ganglia and neurons, sizes and orientation of nerve strands and immunoreactivities. Ganglia were situated at different topographical levels in the lamina muscularis mucosae subplexus, outer proprial and interglandular proprial meshworks in the lamina proprial subplexus with the majority of ganglia occurring in the outer proprial meshwork. The mucous plexus in the intestine of the pig is thus a ganglionated plexus showing marked segmental variation in the amount of intramucosal ganglia and isolated nerve cells. These new observations, calls for a re-examination of the mucous plexus to elucidate the regulatory mechanisms of importance in mucosal functions and consideration of the mucous plexus in the intestine of the pig to be one of the major ganglionated plexuses. 相似文献
124.
125.
An adult female bearded vulture (Gypaetus barbatus) in the Tel Aviv University Research Zoo was found dead without previous clinical signs. The predominant pathologic changes were considerable bloody content in the intestines and enlargement of the liver, which had a rubbery consistency with color changes. Microscopic lesions consisted of multifocal histiocytic infiltration in the liver. Newcastle disease virus (NDV) was isolated from a cloacal swab and from the lungs and liver. Intracerebral pathogenicity index of the virus, as estimated in 1-day-old chicks, was repeated three times and had an average value of 1.68, indicating a velogenic strain. Numerous Clostridium septicum bacteria were found on the intestinal surface, but bioassays in which they were orally administered into chickens and mice revealed that, even though they were heavily multiplied in the intestines, they were nonpathogenic. It seems that NDV, documented for the first time in a bearded vulture in Israel, was the likely cause of sudden death. 相似文献
126.
Lenhardt L Cigankova V Zibrin M Kocisova J Tomkova I Sabo V Boda K Dadasheva OA Gurieva TS Mozes S 《Acta veterinaria》2001,70(2):127-131
The effect of microgravity on functional development of the small intestine of Japanese quails incubated for 2-3 d and hatched on the orbital station MIR was examined. After 5 d of space flight duodenal and jejunal alkaline phosphatase (AP) activity of the experimental group was compared with the AP activity in quails of the same age hatched on the Earth (laboratory controls). Short-term microgravity leading to decreased food intake resulted in significant increase of AP activity in both duodenal and jejunal enterocytes (P<0.001) of the experimental quails. The results suggest that increased AP activity probably reflects the delayed functional development of the small intestine as a consequence of inappropriate food intake during non-physiological conditions of space flight. 相似文献
127.
Changes in the EU legislation on Trichinella inspection--new challenges in the epidemiology 总被引:7,自引:0,他引:7
Kapel CM 《Veterinary parasitology》2005,132(1-2):189-194
The European Union (EU) countries are searching for new ways to certify meat free of Trichinella; however, with the expansion of the EU, the acceptance of a unilateral method is complicated by the variability of pig and human trichinellosis among EU countries, where significantly higher prevalence rates have been observed in the newly added eastern countries. Several attempts have been made to define Trichinella-free areas, but certification of Trichinella-free pig production farms appears to be the only feasible approach. The increasing prevalence of the non-encapsulating species, Trichinella pseudospiralis, in game, domestic pigs and humans has eliminated the compression technique from the new EU legislation to be enacted in 2006. Also, the observation that several species of Trichinella tolerate freezing in horse meat for up to 4 weeks has forced a change in legislation as well where freezing is no longer an option for certifying horse meat. Because current serological detection methods are not suited for meat inspection, classical direct detection methods and inactivation by freezing remain the methods of choice for pork. It has been proposed, therefore, to automate direct inspection methods as a cost effective alternative to certify pig farms free of Trichinella. 相似文献
128.
Zaks KL Tan EO Thrall MA 《Journal of the American Veterinary Medical Association》2005,226(9):1516-8, 1500
A 5-year-old pit bull-type dog was examined because of lethargy and black feces, and a presumptive diagnosis of methemoglobinemia was made on the basis of grossly visible brown discoloration of the mucous membranes and urine. Heinz body formation was seen on examination of blood smears, and severe anemia developed 3 days later. The dog did not have any history of exposure to toxins or drugs that have been associated with Heinz body formation. The only remarkable historical finding was that the dog had been wandering loose the day prior to initial examination and returned home smelling strongly of skunk spray. Skunk spray contains thiols and other compounds that are strong oxidizing agents. It was speculated that the methemoglobinemia and Heinz body anemia were a result of exposure to these compounds. Skunk interactions with dogs usually have malodorous but otherwise harmless results. However, findings in this dog suggest that more serious consequences may develop in isolated cases. 相似文献
129.
K. O. Ali U. T. Brenøe 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):246-252
Three genotypes of chickens including one commercial broiler (CB) and two others from the Norwegian gene bank [Barred Plymouth Rock (BPR) and Jærhøn (JH)] were raised from 1 day to 20 weeks of age with a free choice of a commercial starter ration and whole-grain wheat. Body weights and pen-feed intakes were recorded every 2 weeks. The weight–age data were fitted to a Gompertz growth equation where, among other parameters, adult body weights were estimated and used for size scaling. The heavier CB chickens consumed more food (starter and wheat) than the other two genotypes. The maximum proportions of whole-grain wheat in the diet were 0.56, 0.68 and 0.75 for BPR, CB and JH birds, respectively. Although the proportions of whole-grain wheat were similar between the genotypes as age progressed, their maintenance requirement and feed intakes relative to body weight suggested a major genetic role and a possible interplay of both genetic potential and body size. 相似文献
130.
Mariette van den BergSimone O. Hoskin PhD Chris W. Rogers Alex Grinberg PhD 《Journal of Equine Veterinary Science》2013
Abrupt dietary transitions and feeding of rapidly fermentable diets are common practices in the horse industry and have been associated with digestive and metabolic disorders that can impair the performance of horses. The present study investigated the effect of dietary transition from pasture grazing to confinement with concentrate feeding, and back, on fecal pH and bacterial populations of Streptococcus spp and Lactobacillus spp. Six Thoroughbred fillies, previously grazing perennial ryegrass and white clover-based pasture, were housed in individual stalls and fed an increasing ratio of concentrate to conserved forages for 13 days (days 1-13), followed by an abrupt transition back to only pasture-grazing for 3 days (days 14-16). The concentrate was initially offered at 0.83 kg dry matter (DM)/d and increased to 5 kg DM/d, whereas ensiled alfalfa was initially offered at 0.61 kg DM/d, increasing to 1.22 kg DM/d. Meadow hay was initially offered at 6.73 kg DM/d, decreasing to 1.6 kg DM/d. Fecal specimens were collected daily for determination of pH, and every 2 days for quantitative analysis of Streptococcus spp and Lactobacillus spp. Mean fecal pH increased significantly from pasture baseline values (pH 6.18) during the initial confinement and supplementation on day 1 (6.37), day 2 (6.52), day 3 (6.58), and day 4 (6.43) (standard error of mean [SEM]: 0.056; P < .001). By day 5, mean fecal pH values had decreased to, and remained at, baseline values until the horses returned to pasture, when another increase occurred at day 15 (6.45). Fecal colony forming units (cfu) of Streptococcus spp and Lactobacillus spp increased linearly (r = 0.94; P < .001) from 6.0 and 6.1 log10 cfu/g on day -4, to 7.8 log10 cfu/g on day 14 (SEM: 0.2 P < .001), respectively. Fecal cfu decreased on return to a pasture-only diet (P < .001). In this study, the increment of bacterial populations was associated with a relatively stable fecal pH and highlights the difficulty in identifying the effects of dietary transition on the equine hindgut health, without microbial culture. 相似文献