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41.
Van Hoogmoed LM Agnew DW Whitcomb M Hyde DW MacDonald MH Snyder JR 《American journal of veterinary research》2002,63(5):738-743
OBJECTIVE: To describe the ultrasonographic and quantitative histologic effect of injecting 2% iodine in almond oil (IAO) and ethanolamine oleate (EO) in the medial and middle patellar ligaments of horses and to determine whether a difference in response exists between IAO and EO treatment. ANIMALS: 10 healthy horses. PROCEDURE: In 5 horses, the medial and middle patellar ligaments of 1 limb were injected with EO, whereas IAO was injected in the medial and middle patellar ligaments of another 5 horses. Ultrasonographic evaluation was performed on the experimental and control limb before injection of IAO and EO and prior to euthanasia to determine cross-sectional area and evaluate fiber pattern. The patellar ligaments were harvested 2 weeks after injection and examined histologically to evaluate the inflammatory response, fibroplasia, and chondroid metaplasia. RESULTS: Injection of the patellar ligaments with IAO resulted in a greater increase in cross-sectional area on ultrasonography than EO. Both agents caused a decrease in echogenicity of the ligament. Histologically, significantly greater infiltration of inflammatory cells and fibroplasia developed after injection with IAO, compared with EO. Both agents resulted in significantly greater fibroplasia relative to control specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Injection of the medial and middle patellar ligaments with IAO induces more severe inflammation and fibroplasia than EO. Maturation of the inflammatory and fibrous response may contribute to resolution or attenuation of upward fixation of the patella by subsequent stiffening of the ligaments. 相似文献
42.
1. Broiler breeder females were reared on one of three growth curves (ad libitum, conventional or modified restriction) and given rations containing a high or low concentration of crude protein. After the peak rate of lay they were fed ad libitum or a decreasing quantity of food in response to declining egg production. The welfare of the birds was assessed by determining the changes in indices of welfare at 36, 48 and 60 weeks of age. 2. Body weight increased rapidly in restricted birds fed ad libitum post-peak and water intake declined. 3. Post-peak food restriction was associated with a decrease in resting and increased drinking and spot-pecking activities. Birds that were food restricted during rearing spent more time foraging and spot-pecking at 36 and 48 but not 60 weeks of age. 4. Immune function increased with age but was not affected by the experimental treatments. The heterophil-lymphocyte ratio in birds fed ad libitum during rearing was numerically lower at 36 and higher at 48 and 60 weeks of age compared with restricted birds. 5. There was no effect of treatment on plasma corticosterone concentration. Creatine kinase activity was high at 60 weeks in treatments that were characterised by poor reproductive status and the activities of other enzymes reflected differences in reproductive status and mortality. 6. There was no long-term welfare or production advantage from feeding low protein rations or more generous feeding during the rearing period compared with conventional food restriction programmes. 相似文献
43.
Fang MZ Lee MH Lee YS Kim YC Lee BM Cho MH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(3):201-205
At present, the effect of cyclin D2 implicated in cell cycle regulation, differentiation, and oncogenic transformation is not fully confirmed. To better elucidate the role of cyclin D2 in controling the cell proliferation, cyclin D2 expression level was determined at the early initiation and promotion stages during the in vitro two-stage transformation process of Balb/3T3 A31 cells. N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced G2/M-arrested cells expressed low level of cyclin D2 mRNA, while the contact-inhibited nonproliferating cells expressed high level of cyclin D2 mRNA. In the transformed proliferating cells at the promotion stage, cyclin D2 mRNA was not expressed. These data suggest that cyclin D2 expression may be associated with the type of growth arrest and nonproliferating state, but not with the cell proliferation and transformation. 相似文献
44.
Mentschel J Deininger MH Schluesener HJ Claus R 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(4):184-188
The allograft inflammatory factor (AIF-1/daintain) is a hormone-like peptide produced by activated monocytic cells in a variety of traumatic, inflammatory and degenerative lesions. Gut-derived AIF-1 has been shown to modulate insulin production and to attenuate autoimmune diabetes. As the localization of this gastrointestinal peptide in the porcine duodenum is not known and the pig is a convenient model for the study of nutritional modulation of the mucosal immune compartment, we have localized expression of AIF-1 by immunohistology in the duodenum of either malnourished (energy and protein supply 50% of demands, n = 5) or optimally fed pigs (n = 5). AIF-1 macrophages were predominantly located at the villus tip. The number of positively stained cells per high-power field was significantly (P < or = 0.001) higher in the malnourished pigs (74.6 +/- 2.44; least square means +/- SEM) compared to optimally fed pigs (32.56 +/- 1.99). It is likely that the effect in malnourished pigs can be explained by a more pronounced antigen contact of macrophages due to loss of epithelial integrity. Thus, AIF-1 is a novel marker for the study of the nutritional regulation of the mucosal immune system of the pig. AIF-1 expression in the duodenum was further validated by polymerase chain reaction and sequencing. Surprisingly, we detected a slight deviation from the original sequence (probably representing an allelic variation) and an AIF-1 splice variant, previously not known to occur in pigs. 相似文献
45.
Uystepruyst C Coghe J Dorts T Harmegnies N Delsemme MH Art T Lekeux P 《Veterinary research》2002,33(6):709-724
The aim of this study was to evaluate the effect of body positioning immediately after delivery on respiratory and metabolic adaptation to extra-uterine life in newborn calves. One hundred and one Belgian White and Blue calves were delivered at term by an elective caesarean section and were assigned into three categories according to the body position imposed immediately after umbilical cord rupture: 71 calves were placed in lateral recumbency; 16 calves were placed in sternal recumbency and 14 calves were suspended by the hind legs for less than 90 seconds (75 +/- 5 s). Following this initial body position, the calves were allowed to move without restraint. They were examined at birth, 5, 15, 30, 45 and 60 minutes, and 2, 3, 6, 12 and 24 hours after birth by the following measurements: physical examination, heart rate, arterial blood gas analysis, pulmonary function tests using the esophageal balloon catheter technique, arterial and venous blood acid-base balance analysis, rectal temperature, jugular venous blood sampling for the determination of blood glucose, plasma lactate and serum cortisol concentrations, haematologic variables and passive immune transfer variables. Body positioning immediately after delivery clearly influenced respiratory and metabolic adaptation to extra-uterine life in term calves delivered by an elective caesarean section. Systematic sternal recumbency and suspension by the hind legs for less than 90 seconds immediately after umbilical cord rupture had a positive functional impact on postnatal pulmonary mechanics and gas exchange and on postnatal correction of mixed acidosis present at birth, contributing in turn to an enhanced passive immune transfer. These two body positions should be encouraged to improve adaptation at birth in healthy term calves delivered by an elective caesarean section. Evaluation of possible side-effects is required before application in severely asphyxiated calves. 相似文献
46.
The importance of seminal plasma on the fertility of subsequent artificial inseminations in swine 总被引:1,自引:0,他引:1
Rozeboom KJ Troedsson MH Hodson HH Shurson GC Crabo BG 《Journal of animal science》2000,78(2):443-448
Yorkshire x Landrace sows and gilts were used in a 3x2 factorial arrangement of treatments to determine the effect of uterine inflammation induced by either killed spermatozoa (KS) or bacterial lipopolysaccharide (LPS) on the fertility of a subsequent, optimally timed AI. Estrus was detected with a mature boar twice daily. Twelve hours after the first detection of estrus, females received intrauterine infusions of an inflammatory stimulus consisting of a 100-mL dose of extender containing 3x10(9) KS (n = 40), 20 microg of LPS (n = 40; positive control) or extender alone (n = 40; negative control). An insemination was performed 12 to 18 h later with 3x10(9) motile spermatozoa (i.e., fertile AI) suspended in either 100 mL of seminal plasma (SP; n = 60) or extender replenished with of estrogens (5 microg of estradiol-17beta, 4.5 microg of estrone sulfate, and 2 microg of estrone; n= 60). Transcutaneous ultrasound was performed at the time of fertile AI and again 24 h later to detect the presence or absence of preovulatory follicles. A fertile AI performed within 24 h before ovulation was considered optimal. Conception (CR) and farrowing rates (FR) were greater in females that received a fertile AI diluted with SP compared with extender (P<.01), and there was a significant (P<.05) treatment x fertile AI dilution medium interaction for both CR and FR. Females that received a fertile AI 12 h after infusion of extender had similar CR and FR regardless of fertile AI dilution medium. After inducing an inflammatory response with either KS or LPS, CR and FR were higher in females that received a fertile AI diluted with SP compared with fertile AI dilution with extender (P<.05). The effects of treatment and AI dilution media and their interactions were not significant for litter size in females that farrowed. These results show that the fertility of a subsequent AI can be impaired when semen is deposited into an inflamed environment created by an earlier AI, and this impairment was offset by inclusion of SP in the subsequent insemination. 相似文献
47.
Stoffel MH Wahli T Friess AE Burkhardt-Holm P 《Schweizer Archiv für Tierheilkunde》2000,142(5):263-267
Nonylphenol is a biodegradation product of a widely used group of non-ionic detergents. Because of its ubiquitous distribution and persistence, nonylphenol is present in surface waters as a pollutant. Little is known about its biological effects at environmentally relevant concentrations other than its action as a xenoestrogen. The goal of the present paper was to study the trout gill surface epithelium as the major interface between fish and water in view of possible morphological alterations due to exposure to nonylphenol. Rainbow trout were intermittently exposed to 10 micrograms/l nonylphenol and gill samples from experimental and control animals were investigated by scanning electron microscopy. Gill surface epithelium was scrutinised for changes in chloride cell density and their status regarding cell surface modifications. In addition, chloride cell fractional surface area (CCFA) was determined by morphometrical methods. Statistical analysis revealed a highly significant increase of CCFA in animals exposed to nonylphenol as compared to control animals (P = 0.0001). Semi-quantitative assessment of the other parameters suggested a higher chloride cell density and a larger proportion of chloride cells bearing microvilli. Taken together, these results provide evidence that exposure of trout to nonylphenol is associated with a substantial increase in the active interface of chloride cells with water. We interpret these findings as being a means to further the fish's capacity for calcium exchange. 相似文献
48.
Drén CN Kant A Van Roozelaar DJ Hartog L Noteborn MH Koch G 《Acta veterinaria Hungarica》2000,48(4):455-467
The pathogenesis of chicken infectious anaemia virus (CAV) infection was studied in 6-week-old and one-day-old SPF chickens inoculated intramuscularly with graded doses of Cux-1 strain (10(6)-10(2) TCID50/chicken). Viraemia, virus shedding, development of virus neutralizing (VN) antibodies and CAV distribution in the thymus were studied by virus isolation, polymerase chain reaction (PCR), immunocytochemistry (IP) and in situ hybridization until postinfection day (PID) 28. In 6-week-old chickens infected with high doses of CAV, viraemia and VN antibodies could be detected 4 PID and onward without virus shedding or contact transmission to sentinel birds. However, virus shedding and contact transmission were demonstrated in one-day-old infected chickens. In the 6-week-old groups infected with lower doses, VN antibodies developed by PID 14, transient viraemia and virus shedding were detected. The thymus cortex of all 1-day-old inoculated chickens stained with VP3-specific mAb. Cells with positive in situ hybridization signal were fewer and scattered throughout the thymus tissue of the one-day-old inoculated chickens as compared to IP-positive cells. These results suggest that early immune response induced by high doses of CAV in 6-week-old chickens curtails viral replication and prevents virus shedding. 相似文献
49.
Antibacterial effect of chloramphenicol, thiamphenicol and florfenicol against aquatic animal bacteria 总被引:12,自引:0,他引:12
Ho SP Hsu TY Che MH Wang WS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(5):479-485
The minimum inhibitory concentration (MIC) was measured to evaluate the antibacterial activities of chloramphenicol (CP), thiamphenicol (TP) and florfenicol (FFC) against the aquatic bacterial isolates from soft-shell turtles, fish and shellfish. Amoxicillin (AMPC), oxytetracycline (OTC) and oxolinic acid (OA) were included to compare with above protein synthesis inhibitors. The results showed that the order of MIC range of the isolates from soft-shell turtles for tested drugs was OA>FFC, CP>TP> AMPC, OTC. The percentage of the resistant strains indicated that OA was the lowest (7.14%) and OTC was the highest (85.07%). The order of antibacterial activity against the isolates from fish was OA>FFC>CP>AMPC>OTC>TP. The percentage of the resistant strains revealed that OA (13.64%) and OTC (80.91%) were the lowest and the highest, respectively. For the isolates from shellfish, the order of antimicrobial activity was OA>CP, FFC>AMPC, OTC, TP. TP showed the greatest percentage of the resistant strains (58.7%), but that of OA was the lowest (4.35%). The most common resistant patterns of the isolates from turtles, fish and shellfish were AMPC-OTC, CP-TP-AMPC-OTC, and FFC-CP-TP-AMPC-OTC, respectively. There were partially-complete resistance of the resistant isolates among CP, TP and FFC. The findings indicated that previous treatment might affect the choice of drug to use for aquatic bacterial diseases. 相似文献
50.