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71.
P Dom F Haesebrouck 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(4):303-306
The virulence of a NAD-independent Actinobacillus pleuropneumoniae serotype 2 strain and NAD-dependent serotype 2, 3 and 9 strains was compared under experimental conditions. Hysterectomy-derived piglets were inoculated endobronchially with 50-500 cfu of these strains. All 23 piglets inoculated with the NAD-dependent strains developed acute disease within 12 hours post inoculation. Twenty-two of these piglets died within 24 hours after the first clinical signs. Three of nine piglets inoculated with the NAD-independent strain did not develop clinical disease. In the other six piglets, disease signs were similar as in the piglets inoculated with the NAD-dependent strains. No differences in clinical disease were observed between colostrum deprived piglets and piglets that obtained colostrum from a SPF sow. 相似文献
72.
73.
J. Gonzalez-Soriano E. Rodriguez-Veiga P. Martinez-Sainz S. Mayayo-Vicente P. Marin-Garcia 《Anatomia, histologia, embryologia》1995,24(1):61-65
As in the number of mammals, the most prominent feature of the ganglion-cell layer in the retina of the German shepherd dog is the sharp increase in the density of ganglion cells in the central area. There is an area of maximum density and also a ‘cat-like’ visual streak, located dorsal to the optic disc. The isodensity lines of ganglion-cell distribution is roughly concentric. Their values vary from 5300-13 000 cells/mm2 in the central area, with the cells densely packed, to 1000 cells/mm2 or less in the periphery, where the cells are sparsely distributed. There were some individual differences amongst the animals studied, although all of them were pure-bred dogs. This suggests that the configuration of the retina in the canine species is not only dependent on the breed itself but also on some other parameters such as phylogenetic heritage, environment, aptitude, lifestyle, or even training. 相似文献
74.
P E Holt 《Research in veterinary science》1989,47(1):117-118
Pressure changes in the urinary bladder due to respiration were measured in 75 bitches. The changes fell within a narrow range (0.5 to 2.5 cm water) and were unaffected by size or whether the bitches were entire or spayed. Significant differences were found, however, between continent (mean +/- SD, 1.1 +/- 0.4 cm water) and incontinent (mean +/- SD, 1.4 +/- 0.5 cm water) animals (P less than 0.01). 相似文献
75.
Michael R. Metcalf DVM MS Lloyd P. Tate DVM Loouis C. Sellett MS 《Veterinary radiology & ultrasound》1989,30(2):80-87
76.
L G Rickard G L Zimmerman E P Hoberg P W Lockwood D W Weber R Miller 《Veterinary parasitology》1989,33(2):125-133
The effectiveness of the morantel sustained release trilaminate (MSRT) in controlling gastrointestinal nematodes through a grazing season was evaluated using 60 yearling beef stocker calves randomly divided into 2 groups of 30 animals each. In April 1985, the calves comprising the treatment group each received an MSRT designed to release morantel tartrate continuously for 90 days while those of the control group remained unmedicated. All animals were weighed and samples of rectal feces were taken at 14-day intervals, beginning on Day 0, until trial termination (Day 168). At trial termination, 10 control and 10 treated calves were necropsied for recovery of gastrointestinal nematodes. Three sets of parasite-na?ve tracer calves were utilized to evaluate the initial, interim and final levels of pasture contamination by nematode larvae. Overall, the use of the MSRT resulted in a 75.5% reduction (P less than 0.001) in output of nematode eggs from the principals, an 81.8% reduction (P less than 0.001) in numbers of gastrointestinal nematodes in principals (at trial termination), and a 96.9% reduction (P less than 0.05) of pasture larval nematode contamination (as indirectly indicated by parasite burdens in tracer calves). The mean weight advantage of treated calves was 16.6 kg per head (P less than 0.001). 相似文献
77.
Synchronization of estrus in dairy goats given norgestomet and estradiol valerate at various stages of the estrous cycle. 总被引:1,自引:0,他引:1
K N Bretzlaff L C Nuti R G Elmore S A Meyers J N Rugila S P Brinsko T L Blanchard P G Weston 《American journal of veterinary research》1992,53(6):930-934
Dairy goats were given subcutaneous implants with 3 mg of norgestomet (NOR) and IM injections of 0.625 mg of estradiol valerate and 0.375 mg of norgestomet on day 0 of the estrous cycle (estrus; NOR 0, n = 18), on postestrus day 4 (NOR 4, n = 18), or on postestrus day 11 (NOR 11, n = 15). Ear implants were removed after 9 days. Mean (+/- SE) hours from removal of ear implants to onset of estrus and proportion of goats responding were 36 +/- 3.8 and 83%, 33 +/- 4.0 and 61%, and 36 +/- 2.7 and 93% for groups NOR 0, NOR 4, and NOR 11, respectively. There were no significant differences between treatment groups in time to onset of estrus. The percentage of goats in group NOR 11 that had signs of estrus was significantly greater than the percentage of goats in group NOR 4. Of the goats in groups NOR 0, NOR 4, and NOR 11 that had signs of estrus, 53, 55, and 86%, respectively, had onset of behavioral estrus between 24 and 48 hours after implant removal. All goats that had signs of estrus had onset of behavioral estrus between 12 and 72 hours after implant removal. Mean (+/- SE) hours from removal of ear implants to time of peak concentrations of luteinizing hormone (LH) were 49 +/- 4.1, 49 +/- 3.8, and 49 +/- 4.0 for groups NOR 0, NOR 4, NOR 11, respectively (not different). The percentage of goats in group NOR 11 that had LH peaks was significantly greater than the percentage of goats in group NOR 4.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
78.
D E Granstrom R K Ridley Y Baoan L J Gershwin P M Nesbitt L A Wempe 《American journal of veterinary research》1989,50(4):571-574
Eight bovine hearts with lesions of eosinophilic myositis (EM) and 2 bovine hearts without EM lesions were collected at slaughter. Blood samples from these 10 hearts, and the heart of a newborn calf also were collected. Histologically, Sarcocystis cruzi was identified in the 8 hearts with EM lesions and the 2 hearts without EM lesions, but not in the heart of the newborn calf. Serum was harvested from the 10 blood samples and was used in homologous, modified, passive cutaneous anaphylaxis tests. Antigen was prepared from S cruzi bradyzoites isolated from the 2 hearts without EM lesions. Serum samples from the 8 cattle with EM lesions reacted positively to S cruzi antigen. When heat-inactivated IgE in serum (56 C for 4 hours) was used, all passive cutaneous anaphylaxis responses were considered negative. Using ELISA, serum IgE concentrations from the 10 cattle with and without EM lesions were 2.2 to 9 U/ml. As determined by radial immunodiffusion, IgM concentrations were 80 to 215 mg/dl. Immunoglobulin G concentrations were 420 to 2,050 mg/dl, but most were less than or equal to 1,700 mg/dl. Immunoglobulin A concentrations were 0 to 62 mg/dl; 1 steer with EM lesions had 0 mg/dl. Double-gel immunodiffusion confirmed the presence of Sarcocystis-specific precipitating antibodies. Sera from the 10 cattle with and without EM lesions formed at least 1 precipitin band. 相似文献
79.
P.A. Harris 《Research in veterinary science》1993,54(3):179
The effect of feeding diets with low, adequate and high sodium contents on plasma aldosterone concentrations in horses and ponies was evaluated using human immunoassay kits. The effect of moderate to high intensity exercise of up to six minutes duration on plasma aldosterone concentrations in three thoroughbred- horses was also investigated. On an adequate sodium diet plasma aldosterone concentrations increased to a peak around four hours after feeding. Little daily variation was found in the pre-feeding aldosterone concentrations over three days. Feeding additional salt resulted initially in no increase in plasma aldosterone concentrations in three out of four animals. After five days all four animals had lower pre-feeding concentrations, an increase in the magnitude of the response to feeding but a decreased rise in absolute concentration. Feeding a diet with a decreased sodium content for several months did not result in a consistent change in the pre-feeding aldosterone concentrations although there were times when all three animals showed an increase in the magnitude of the aldosterone response to feeding. No correlation between changes in the fractional electrolyte excretion values determined and alterations in aldosterone response was found. Exercise resulted in a marked increase in aldosterone concentrations. The expected biological response to feeding and exercise was demonstrated with an acceptable level of reproducibility and repeatability. Samples had similar values when assayed by either of the kits evaluated. 相似文献
80.
P. G. PSALLIDAS 《EPPO Bulletin》1997,27(4):511-517
The history of hyperplastic canker of almond, caused by Pseudomonas amygdali , its evolution and the present situation in Greece are reviewed. Its main aspects, causal agent, symptomatology, epidemiology and control measures are described. The main characteristics differentiating the pathogen from some other pseudomonads pathogenic to fruit trees are also reported. 相似文献