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931.
Our study was designed to ascertain whether a flexible videoscope could be used to efficiently monitor ulcers of the pars esophagea in a large group of grower-finisher swine. Gastroscopy was performed on 2 separate occasions in 32 pigs following anesthesia with intravenous pentobarbital, and ulcers of the pars esophagea were subjectively graded. The pigs were then necropsied. Grades from the second endoscopic examination were compared for agreement with grades derived from gross inspection of the pars esophagea at necropsy, and with grades derived from histopathologic examination of sections of the same region. The pars esophagea was adequately visualized in all endoscopic examinations. The average duration of each examination, from anesthetic induction, was approximately 8 min. Gastroscopy permitted appreciation of a wide range of focal and diffuse superficial and deep ulcerative lesions of the pars esophagea, but failed to unequivocally identify parakeratosis of the pars esophagea. Agreement between endoscopic and subsequent necroscopic and histopathologic gradings of ulcerations was poor. We concluded that the use of a flexible videoscope permitted rapid inspection of the pars esophagea, and was therefore a practical method of experimentally monitoring the progression of spontaneous gastric ulcers in pigs. We also postulated that the poor agreement between endoscopic and postmortem findings occurred because endoscopy was possibly more sensitive at detecting small and superficial ulcerations. However, further studies are needed to verify the accuracy of endoscopic diagnosis of gastric ulcers in the live pig.  相似文献   
932.
933.
The objectives of this study were to determine the concentration of itraconazole achieved in corneal tissue and aqueous humour after topical application of a 1% itraconazole ointment; to determine the effect of including dimethyl sulphoxide (DMSO) in the ointment on achievable ocular tissue itraconazole concentrations; and to assess if any gross or histopathologic ocular toxicity results from the topical application of 1% itraconazole with or without the addition of DMSO.
The experimental trial consisted of 6 horses considered to have normal eyes. Each horse had one eye treated with 0.3 mL of 1% ultra-micronized itraconazole ointment and the fellow eye with 0.3 mL of 1% itraconazole/30% DMSO ointment. The ointment was applied every 6 h for a total of 28 treatments. Both ointments were well tolerated and no gross or histopathologic abnormalities developed during the trial.
Corneal tissue and aqueous humour concentrations of itraconazole were determined using high performance liquid chromatography. Corneal tissue concentration averaged 1.1 (± 0.4) μg/g in horses treated with the 1% ultra-micronized itraconazole ointment and 7.9 (± 3.3) μg/g for those treated with the 1% itraconazole/30% DMSO ointment; there was a statistically significant difference between ointments ( P = 0.005) No itraconazole could be detected in the aqueous humour in either treatment group.  相似文献   
934.
Postmortem bronchoalveolar lavage of feline immunodeficiency virus-infected cats indicated an alveolitis process, and histological examination of their lungs confirmed the occurrence of alveolitis, parenchymatous lymphoplasmocytic infiltration and myomatosis. Similar lymphoid interstitial pneumonitis has been described in human and animal lentiviral diseases: lymphocytic interstitial pneumonitis in hiv-1-infected human beings, and maedi in sheep infected by the maedi-visna virus. Such lymphoid interstitial pneumonitis may thus be a common feature of lentiviral infections.  相似文献   
935.
1. The egg yolk: albumen (Y:A) ratio during the laying year was investigated in a commercial strain (Hisex) when natural zeolite was added to a layer's diet. 2. Dietary natural zeolite (NZ) increased both egg weight and albumen weight, while yolk weight was not significantly affected. 3. The Y:A ratio was less (more albumen) in eggs laid by hens on zeolite treatments. It was concluded that by feeding NZ it is possible to alter the Y:A ratio.  相似文献   
936.
A subpalpebral lavage catheter is commonly used to administer medications in the treatment of infectious keratitis in horses. Drugs may mix in the subpalpebral lavage catheter, potentially affecting antimicrobial efficacy. The objective of this study was to determine the in vitro antimicrobial efficacy of combinations of commonly used ophthalmic preparations. An agar gel diffusion bioassay was used to determine the antibiotic activity of a number of antimicrobial, antifungal, mydriatic, and antiproteinase drug combinations. Drug mixtures were allowed to sit in a syringe at ambient temperatures and room lighting, for 1 (T1) and 6 hours (T2). The antibacterial efficacy was determined by measuring the zone of inhibition around wells containing the drug combinations after overnight incubation at 37°C and comparing them with the zone of inhibition around the antimicrobial alone. Combinations were tested against Pseudomonas aeruginosa and Streptococcus zooepidemicus. There was no significant decrease in the zone of inhibition, compared with controls, for the majority of combinations tested. Significantly smaller zones of inhibition were identified for the following combinations: (1) tobramycin, cefazolin, natamycin, and serum (T1) and (2) tobramycin, cefazolin, natamycin, serum, and atropine (T1) compared with tobramycin alone; (3) ciprofloxacin, cefazolin, natamycin (T1) compared with ciprofloxacin alone; (4) triple antibiotic ophthalmic solution (TAB) and natamycin (T6); (5) TAB, natamycin, and serum (T6); and (6) TAB, natamycin, serum, and atropine (T6) compared with TAB alone. Admixture does not affect in vitro antibacterial efficacy for the majority of ophthalmic preparations, although efficacy of TAB may be decreased compared with the drug alone.  相似文献   
937.
The objective of this study was to evaluate neutrophil oxidative metabolism and haemogram in sheep experimentally infected with Haemonchus contortus and supplemented with selenium and vitamin E. Twenty male Corriedale sheep were utilised and distributed into four experimental groups each with five animals infected with larvae: G1‐ supplemented with sodium selenite, 0.2 mg/kg body weight (bw) given intramuscularly (IM); G2‐ supplemented with sodium selenite and vitamin E, 0.2 mg/kg bw and 2000 IU per animal, respectively, both IM; G3‐ supplemented with vitamin E, 2000 IU per animal IM; G4‐ not supplemented. A haemogram and the number of parasite eggs were determined in samples of blood and faeces, respectively, on days zero (T0), 20 (T1), 40 (T2) and 60 (T3) and nitroblue tetrazolium (NBT) assays were performed on heparinized blood samples taken on days zero, 30 and 60. A lower total leucocyte count was detected in G1 in relation to G4 at T4. Lymphocytes were reduced in G1 in relation to G3 and G4 at T3. In both non‐stimulated (NBT‐NS) and stimulated (NBT‐S) dye reduction assays, there was reduced activity at 60 days, in relation to other times in the groups treated with selenium (G1 and G2). On the basis of results obtained, we conclude that supplementation with selenium provides better antioxidant protection to neutrophils.  相似文献   
938.
Bartonella henselae is considered an emerging pathogen of veterinary and medical interest that can be occasionally transmitted to humans. Cats are considered to be the only reservoir host for B. henselae. In this study, we used a nested-PCR assay to investigate the prevalence of B. henselae and Bartonella clarridgeiae DNA in peripheral blood samples, fine needle lymph node aspirate specimens and oral swabs from 85 cats in order to develop an easy diagnostic strategy for the selection of infection-free cats that are being considered as pets, especially for immunocompromised patients. Overall, molecular analysis showed that 71 cats (83.5%) tested PCR positive for the presence of B. henselae DNA. PCR amplification of DNA B. henselae produced positive products from lymph node aspirate specimens (62/85; 72.9%) similar to those obtained from blood samples (60/85; 70.6%) and higher than those from oral swabs (51/85; 60%) of cats. No PCR product was obtained for B. clarridgeiae. The simultaneous analysis of three different clinical samples in our study increased the diagnostic possibilities for B. henselae infection in the examined cats from 60–72.9% to 83.5%. Lymph node aspirates were found to be the most effective clinical samples for the detection of B. henselae and blood samples were the next best. Oral swab samples were used in this study with good results when considered in combination with blood and/or lymph node aspiration. The use of nested-PCR assay on these three clinical samples may enhance the diagnostic sensitivity for bartonellosis in cats irrespective of the clinical status of animals.  相似文献   
939.
A cross sectional survey of duck production was carried out in 2002 on 771 traditional, semiscavenging household duck farms on the coastal Island of Hatia. We determined the socioeconomic characteristics of duck farmers and their management systems, identified the factors associated with egg production, and measured the level of selected duck diseases and current preventive strategies. Household family size varied from 1 to 14 individuals and women were the main caretakers of ducks. Around 34% of keepers were illiterate. Most duck products (eggs and meat; 85%) were sold at the local market. Duck houses were poorly ventilated and a variety of bedding materials were used. Feed was available in nearby scavenging areas; however, additional feed was frequently supplied by farmers. Almost all farmers (96%) ranked the rainy season as the best time for rearing ducks due to greater feed availability. The annual egg production was 79 eggs per layer with a weight of 48 g and a hatchability rate of 87%. Egg production varied by zone (p < 0.05). The odds of suboptimal egg production was 0.5 times lower in educated farmers (p = 0.001). The odds of suboptimal egg production was 2.5 times more likely in ducks that attained sexual maturity at >22 weeks (p<0.001). Most farmers ranked duck plague as the most important disease, followed by duck cholera, botulism, and duck viral hepatitis. Preventive vaccination was sporadic and used by few farmers (28%). There are significant opportunities for improved duck production on the Island of Hatia and in Bangladesh generally.  相似文献   
940.
Background: Coagulopathies detected in horses with gastrointestinal problems seem to be associated with poor outcome. Plasma D‐Dimer concentration is a sensitive test for assessing coagulopathies. Hypothesis: Plasma D‐Dimer concentration tested on admission is related to diagnosis and outcome in horses with colic. Animals: Four hundred and ninety three horses referred for evaluation of abdominal pain. Methods: Prospective observational clinical study. Horses were grouped according to diagnosis (medical and surgical intestinal obstructions, ischemic disorders with and without intestinal resection, enteritis, peritonitis), outcome (survivors, nonsurvivors), and number of coagulopathies (normal profile, 1 or 2 coagulopathies, subclinical disseminated intravascular coagulation [DIC]). Blood samples were collected on admission and plasma D‐Dimer concentration, clotting times (PT and aPTT), and antithrombin activity were determined. Positive likelihood ratios (LR+) were calculated for evaluation of D‐Dimer cut‐off values, which were later tested in a logistic regression model. Results: Horses with enteritis or peritonitis had significantly (P < .001) higher plasma D‐Dimer concentrations and more severe coagulopathies on admission than horses with other diagnoses. Nonsurvivors also had significantly (P < .001) higher plasma D‐Dimer concentrations at presentation than did survivors, and those horses with subclinical DIC on presentation had an odds ratio (OR) 8.6 (95% confidence interval [CI], 3.3–22.5, P < .001) for nonsurvival. Finally, D‐Dimer concentrations >4,000 ng/mL had a LR+ of 5.9 and an OR 8.8 (95% CI, 4.5–17.1, P < .001) for nonsurvival. Conclusion and Clinical Importance: Plasma D‐Dimer concentration measured on admission can be used to facilitate diagnosis and outcome prediction in horses with colic. A potential cut‐off value for nonsurvival was found at approximately 4,000 ng/mL.  相似文献   
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