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91.
92.
An extended disease recording programme in pigs has been carried out by the meat inspection service at Sentralslakteriet, Forus, Stavanger. A data system including 57 disease codes has been applied. In the period 1975–1977 an average of 85,000 baconers were slaughtered yearly. About 39 % of these were given disease remarks; 42–47 % of the lesions were directly related to the parasites Sarcoptes scabiei (rind lesions) and Ascaris suum (white spots in the livers). The thoracic cavity was the most commonly affected part of the body with 30–35 % of all recorded lesions.Sixteen disease codes occurred at frequencies above 0.3 %, and they encompassed approx. 97 % of all recorded lesions. Scabies occurred at an average of 12 % of the fatteners. Parasitic hepatitis of severe and moderate degrees were seen in about 11 %, pleurisy in 7 %, pneumonia — severe and moderate — in 5.4 %, pericarditis in 4.3 %, pyaemia and abscess/-es in 2.5 %, tail lesions in 2.3 %, perihepatitis and other non-parasitic liver lesions in 2.2 %, polyarthritis and arthritis in 1.7 %, tuberculous lesions in the cervical lymph nodes in 0.9 %, peritonitis in 0.9 % and atrophic rhinitis — external lesions — in 0.8 % of the carcasses. The majority of the other 41 disease codes occurred at frequencies below 0.1 %.A seasonal variation was pronounced in scabies, numerous white spots in the liver, and tuberculous lesions in the cervical lymph nodes. It could be noted in pleurisy, pericarditis, perihepatitis and other non-parasitic liver lesions, arthritis and atrophic rhinitis, but not in pneumonias, moderate number of white spots in the liver, tail lesions, pyaemia, abscess/-es, peritonitis and polyarthritis.  相似文献   
93.
From each of two lentogenic Newcastle disease virus (NDV) strains of the type LaSota and Hitchner B1 a virulent subpopulation could be obtained. The two subpopulations were—in comparison to the two parent viruses—more resistant to the lipid solvent chloroform and more stable against thermal degradation. Also, the glycoproteins haemagglutinin and F (fusion) were more stable against thermal inactivation. Electron microscopic observations revealed in terms of size and morphology all of the characteristics of NDV. Both subpopulations possessed, however, the same elution kinetics as their respective parent strains. The intracerebral and intravenous pathogenicity indices as well as the mean death times of the two subpopulations allow to classify these viruses as virulent Newcastle disease viruses.  相似文献   
94.
95.
Histochemical and ultrastructural studies were performed on the lateral musculature from individual female whitemouth croaker, Micropogonias furnieri, at the anterior, medium and posterior regions. Based upon histochemical myosin-ATPase (m-ATPase) determination, diverse types of red, pink and white fibres were discerned. Red muscle had abundant mitochondria and stained intensely for aerobic enzymes, white muscle scarcely stained for the same enzymes and pink muscle responded in an intermediate manner. Both white and pink muscle had few mitochondria. The relative proportion of red muscle increased towards the caudal region; pink muscle diminished towards this region and white muscle modified its proportion only in the anterior region. m-ATPase activity showed differences in relation to the gonadal condition along the body, particularly in the white fibres at the anterior and medium regions.  相似文献   
96.
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   
97.
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   
98.
99.
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   
100.
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   
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