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221.
222.
Tischendorf F Möckel P Schöne F Plonné M Jahreis G 《Journal of animal physiology and animal nutrition》2002,86(9-10):313-325
The effect of conjugated linoleic acid (CLA) on blood lipids [total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triacylglycerols (TAG)] and the fatty acid distribution of the lipoprotein fractions, backfat, muscle fat, and liver lipids were examined in an experiment with two groups of 40 pigs [Pietrain x (Landrace x Large White)] each. The 20 female and 20 male castrated pigs of each group were fed with isoenergetic and isonitrogenous diets supplemented with either 20 g/kg rapeseed oil (control) or 20 g/kg CLA-TAG. The CLA preparation contained 54.2% pure CLA consisting of approximately two-thirds cis,trans/trans,cis-isomers and one-third trans,trans-isomers. The fatty acids of lipoproteins, backfat, muscle lipids and liver lipids were analysed by gas chromatograph (GC). CLA supplementation did not significantly influence blood lipids and the LDL to HDL ratio. In the CLA-fed pigs the very low-density lipoprotein (VLDL) contained higher saturated fatty acid (SFA) concentrations at the cost of the monounsaturated fatty acids (MUFA). The percentage of polyunsaturated fatty acids (PUFA) remained unchanged. The highest CLA content was analysed in VLDL (4.00%) followed by LDL (2.78%) and HDL (1.45%). The ratio of cis,cis to trans,trans isomers increased from VLDL over LDL to HDL. The content of SFA, probably in backfat and muscle lipids, increased whereas the part of MUFA decreased as a result of reduced Delta9-desaturase activity. The percentage of PUFA (without CLA) was higher in backfat of the control group in accordance with the dietary PUFA supply. This shift in the fatty acid distribution was not observed in the liver lipids. In all the three tissues analysed, the CLA-fed pigs had a significantly increased CLA content: the highest increase was in the backfat (5.65%), followed by liver lipids (2.41%), and muscle lipids (1.47%). An isomer-specific accumulation was observed for cis,cis-CLA isomers in muscle, and for trans,trans-CLA isomers in backfat. We conclude that CLA supplementation results in a higher SFA content in backfat and muscle lipids but not in liver lipids. There is a discrimination of the trans-10, cis-12 isomer and the trans,trans isomers in the formation of the cell membranes. 相似文献
223.
Teredesai A Wöhrmann T Schlage W 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(10):541-544
A mixed epithelial tumour in the liver of a 24-month-old male Wistar rat from a 30-month inhalation study is described. The rat, which was in a group exposed to low concentrations of diesel exhaust, was euthanized because of emaciation, forced respiration and abnormal gait. Macroscopic examination of the enlarged liver revealed multiple partly confluent beige-red nodules up to 1.5 cm in diameter. Small nodules up to 7 mm in diameter were seen in the spleen. Histologically, the tumour nodules in the liver consisted of hepatocellular and cholangiocellular components. The hepatocellular component consisted of moderately differentiated polygonal to round hepatocytes about twice as large as normal hepatocytes and having hyperchromatic, centrally located nuclei with prominent nucleoli and eosinophilic cytoplasm. Foci of haematopoiesis and focal necroses were prominent. The cholangiocellular component was moderately differentiated and consisted of tubular structures lined by low cuboidal to cylindrical cells showing cytoplasmic basophilia and small dark nuclei without prominent nucleoli. The histological features of the nodules in the spleen corresponded to those of the primary tumour in the liver. Based on these criteria, the tumour nodules were diagnosed as hepatocholangiocellular carcinoma. The immunohistological examination confirmed the diagnosis, i.e. immunostaining for cytokeratins was positive for eight and 18 (hepatocellular carcinoma) and for seven and 19 (cholangiocellular carcinoma) as well as for vimentin (dense fibrous stroma). This tumour is considered to be spontaneous because of its single occurrence. 相似文献
224.
Avian paramyxovirus serotype 1 isolates from the spinal cord of parrots display a very low virulence
Grund CH Werner O Gelderblom HR Grimm F Kösters J 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(9):445-451
The spinal cord of 32 psittacines suffering from proventricular dilatation disease (PDD) was investigated. In six cases, a virus was isolated which upon electron microscopic examination revealed morphological details typical of members of the Paramyxoviridae. All isolates were subsequently characterized as avian paramyxovirus serotype 1 (APMV-1) by type-specific polyclonal antisera. According to their reactivity with APMV-1 specific monoclonal antibodies, the six isolates shared epitopes within the haemagglutinin-neuraminidase spike protein, distinct from pigeon-type paramyxoviruses and the LaSota vaccine strain. This grouping was further corroborated by properties of the haemagglutinin: all isolates showed a very thermosensitive haemagglutination activity and were rapid eluters. Virulence of the APMV-1 isolates in 1-day-old specific pathogen free (spf) chicken was very low, with intracerebral pathogenicity indices between 0 and 0.1. In embryonated spf chicken eggs, psittacine isolates replicated to high titres (10(8.6)-10(10.7) EID50/ml). However, they exhibited a reduced lethality over an observation time of 7 days (10(6.1)-10(8.3) ELD50/ml). In a haemagglutination inhibition test with parrot sera from birds with no history of APMV-1 vaccination, sera reacted preferentially with two isolates compared with APMV-1 vaccine strains LaSota and B1. The other four isolates exhibited a differentiated reaction pattern with the parrot sera, indicating an antigenic inhomogeneity. This is the first report of isolating very low virulent APMV-1 from neuronal tissue of parrots and implications for a possible role in slow progressing disease will be discussed. 相似文献
225.
Müller G Steinbach G Berndt A Köhler H 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(9):429-437
In five experiments, lipopolysaccharides (LPS) of Escherichia coli O26:B6 and O111:B4 were applied intravenously, intramuscularly, subcutaneously or intrabronchially in doses of 5000-15,000 U/kg body mass to a total of 47 weaner pigs and compared with the application of sodium chloride. Different parameters of blood cells were investigated, including cell numbers, in vivo interleukin secretion, radical formation, phagocytosis capacity and IL-6 as well as TNFalpha formation ex vivo. Non-specific effects and dependencies on the type of application and LPS dose are discussed. 相似文献
226.
Cell cultures infected with BHV-1/F(syn), a recombinant bovine herpesvirus 1 (BHV-1) which expresses a synthetic open reading frame encoding the fusion (F) protein of the bovine respiratory syncytial virus (BRSV), showed a cytopathic effect (CPE) indistinguishable from that induced by wildtype BHV-1 although transient transfection experiments demonstrated that expression of the F protein leads to formation of large syncytia. Since it has been shown that glycoprotein M (gM) of pseudorabies virus inhibits BRSV F-induced syncytium formation in transient plasmid transfection experiments [Pseudorbies virus glycoprotein M inhibits membrane fusion. J. Virol. 74 (2000) 6760], the gM ORF of wtBHV-1 and BHV-1/F(syn) was interrupted. Infection of cell cultures with the resulting gM(-) mutant of BHV-1/F(syn) led to formation of syncytia, whereas the CPE in gM(-)BHV-1 infected cells was comparable to the CPE in wtBHV-1 infected cultures. Our results demonstrate that gM is not essential for BHV-1 replication in cell culture and that gM is involved in inhibition of the cell fusion activity of the BHV-1 expressed BRSV F protein. 相似文献
227.
Hultén C Grönlund U Hirvonen J Tulamo RM Suominen MM Marhaug G Forsberg M 《Equine veterinary journal》2002,34(7):699-704
Despite the importance of noninfectious joint diseases in equine medicine, little is known about the acute phase response which may be elicited if the local inflammatory process of noninfectious arthritis is sufficiently strong, Therefore the aim of this study was to monitor the systemic inflammatory response during experimentally-induced noninfectious arthritis by studying the dynamics in serum of the acute phase proteins serum amyloid A (SAA), haptoglobin, fibrinogen and alpha2-globulins. Twenty-four Standardbred horses, age 3-7 years, found healthy on thorough clinical, radiological, haematological and serum biochemical examination, were injected aseptically into the right midcarpal joint with amphotericin B. Blood samples were drawn before induction of arthritis (0 h), and at 8, 16, 24, 36 and 48 h postinduction and then on Days 3, 4, 5 and 15 postinduction. All horses developed lameness with joint effusion and joint heat as well as increased respiratory rate, heart rate and body temperature. The lameness started to decline after 24-36 h and, in most animals, systemic signs disappeared on Day 2 postinjection. The concentration of the acute phase proteins increased following induction of arthritis. The SAA concentrations were higher than baseline concentrations from 16 h postinduction and were maximal at 36-48 h (227 times baseline concentration). The haptoglobin concentrations were higher than baseline concentrations from 24 h and were maximal at 48-96 h (1.14 times baseline concentration). The maximal concentrations of fibrinogen were seen between 36-72 h postinjection and increased on average 0.87 times from baseline concentrations. The fibrinogen concentrations were higher than baseline concentrations from 24 h postinjection. Alpha2-globulins concentrations showed a minor increase and increased 0.55 times from baseline concentrations. The markers had returned to baseline concentrations by Day 15. Our results demonstrate that amphotericin B-induced arthritis in a single joint gives rise to a systemic acute phase response measurable as increased concentrations in serum SAA, haptoglobin, fibrinogen and alpha2-globulins during the first 2 weeks of the condition and, thereby, that such an increase need not be indicative of infectious arthritis. Further research should be aimed at determining whether chronic noninfectious arthritis in the horse gives rise to increased acute phase protein concentrations in serum. 相似文献
228.
Slaughterhouse sampling and examination of urogenital tracts of 499 sows and gilts culled for reproductive reasons from 21 Hungarian herds were performed over a 6-year period. The aim was to estimate the prevalence of different urogenital tract lesions, and to provide sensitivity and specificity estimates for macroscopic and bacteriological examinations in the diagnosis of urocystitis and endometritis. Furthermore, the association between endometritis and urocystitis was assessed. The prevalence of main lesions of the urogenital tract was similar to that reported in other studies. The 'sensitivity' of macroscopic and bacteriological methods was determined statistically by taking histopathology as the 'Gold Standard'. As a result, the 'sensitivity' of macroscopic methods for the diagnosis of endometritis and urocystitis was < or = 18.1% and 47.9%, respectively, while the 'sensitivity' of bacteriology for the diagnosis of the same conditions was < or = 31.8% and 63.0%, respectively. The presumed positive association between urocystitis and endometritis was confirmed; it was not confounded by parity. Animals affected by urocystitis had a 3.5 times higher odds to simultaneously have endometritis than animals without urocystitis. 相似文献
229.
In this paper, the quantitative post-embryonic development of the Asian freshwater fish nematode Camallanus cotti Fujita, 1927, is described. Larval and adult morphometrics were obtained by following the parasite's life cycle experimentally using copepods Macrocyclops albidus (Jurine) as intermediate host and guppies Poecilia reticulata (Peters), southern platyfish Xiphophorus maculatus (Günther) and paradise fish Macropodus opercularis (L.) as definitive host. Additionally, adult worms were obtained from heavily infected paradise fish imported from Singapore. It is suggested that the gradual change in proportions of the worm's somatic body parts reflects the specific ecological role of each developmental stage. The free-living infective first-stage larva seems to be adapted for transmission, as indicated by its relatively long tail, designed to generate host-attracting movements, and its non-functional intestine. The second- and third-stage larvae from the copepod intermediate host seem mainly to invest in trophic functionality, i.e., the development of the buccal capsule and the oesophagus, which are crucial structures for the worm's successful establishment in the definitive fish host. Once in the fish intestine, the larvae enter a period of considerable growth. After the fourth (i.e., last) moult, a 72% increase in average female body length occurs. This is accompanied by doubling the average vulva-tail tip distance and the average tail length. The length of the female hind body expands in an accelerating allometric fashion, and seems to be closely linked to the posterior-wards expansion of the uterus. In the males however, growth seems to cease after the final moult. We conclude that female post-maturational body size, but especially the length of the hind body and the tail, are closely related to reproductive state, i.e., the developmental stage of the offspring in the uterus, and, probably, the worms' age. Any future taxonomical studies of camallanids in general, and C. cotti in particular, should thus be aware of the reproductive state of the females used. 相似文献
230.
Left ventricular systolic function was assessed in 12 healthy dogs with equilibrium radionuclide ventriculography. The results of the analysis were compared to traditional echocardiographic measurements. Left ventricular internal dimensions and volume were measured at the time of end-systole and end-diastole. Ejection fraction--one of the most informative parameters of cardiac function--was calculated in each animal. Values (e.g. EDD, ESD, EDV, ESV) measured by the scintigraphic method were significantly (Student's t-test, p < 0.05) higher than the data obtained by echocardiography. Ejection fraction (EF) was the only parameter that did not differ significantly when comparing the two imaging techniques. The difference between the results of parallel measurements was in inverse ratio to the size of the heart. 相似文献