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81.
82.
Neospora is a cyst-forming coccidian parasite that causes abortions and neuromuscular disorders in a wide variety of mammals. Japanese bovine isolate JPA1 was inoculated intraperitoneally into BALB/c nu/ nu (athymic nude) and BALB/c (congenic wild type) female mice to examine the distribution of parasites and resistance mechanisms to Neospora infection. All the athymic nude mice died within 28 days after intraperitoneal injection of 2 x 10(5) JPA1 tachyzoites, whereas all the congenic wild type mice survived without exhibiting any clinical signs. Tachyzoites were identified in the uterus and pancreas and later spread to many other organs. Most tachyzoites identified in the necrotic foci were localized in the epithelium of the venules and capillaries. Nude mice developed high level of serum interferon-gamma and interleukin-6 as infection proceeded. Inflammatory response to Neospora infection might be mediated by Th1-type dependent cellular immunity.  相似文献   
83.
Twenty outdoor holding tanks (10 m–3 each), were filled with ground water and grouped into five feeding schemes: live zooplankton cultured outside the fish growing tank (LFS); direct nursery pond fertilization schedule in static (MS) as well as in exchanged water (EMS); intermediate conditions between the LFS and MS (IS); and supplementary food system using mixture (1:1) of finely ground mustard oilcake and boiled rice (SFS). Two hundred common carp (Cyprinus carpio) fry were introduced into each of the twenty outdoor tanks maintained at ambient temperature outside the laboratory. After 90 days of rearing, the fish were harvested and analysed for various growth parameters and food conversion efficiency. The average weight of carp attained in the LFS was significantly higher than that in the other four feeding schemes. The frequency distribution of final body weight of common carp showed the preponderance of large and small fish in the LFS and MS, respectively. Likewise, plankton intake by the carp fry was highest in the LFS. The rate of survival was much higher in the LFS as compared with the rest of the treatments. The water quality remained far better in the former than the latter. © Rapid Science Ltd. 1998  相似文献   
84.
Abstract

Many studies have evidenced the negative effects of synthetic fertilizers toward the environment and also the crop products itself. Hence, the improvement of organic fertilizers is necessary to resolve this problem. Seaweeds or marine macroalgae are considered to be an excellent natural resource in different aspects of agricultural fields. Brown macroalgae Turbinaria murayana (TM) is often found in Indonesian coastal areas with high bioavailability throughout the year. This study evaluated the potentials of TM as biofertilizer in tomato plants (Lycopersicum esculentum Mill.). Evaluation of phytohormones present in TM crude extract was conducted with high performance liquid chromatography (HPLC). Macro and micronutrients available in TM crude extract were determined by atomic absorbance spectroscopy (AAS). A concentration of 4% TM crude extract was applied to tomato plants. The vegetative properties of the treated tomatoes were observed such as growth and yield. Current results evidenced the presence of growth-promoting factors (kinetin, gibberellin and ABA) and essential elements (N, P, K, Ca, Fe and Mn) in TM crude extract. Application of 4% TM extract to tomato plants significantly increased vegetative growth compared to untreated plants; plant height, leaf number and branch number, approximately 58.4%, 87.5% and 200%, respectively. Similar results were also found in the response of generative growth. Application of 4% liquid extract significantly improved flower and fruit number compared to control; 53.6% and 125%, respectively. These results suggest that TM crude extract is a potential source for developing organic fertilizers.  相似文献   
85.
Ovariohysterectomy and surgical excision of a vaginal leiomyoma were performed in a bitch exhibiting continuous bleeding from the vulva. Following excision of the tumour, urine retention and urinary incontinence developed. Treatment using drugs and an indwelling catheter was unsuccessful in correcting the disorders and chronic cystitis developed after long-standing urine stagnation in the bladder. The authors resorted to undertaking partial cystectomy in order to correct the condition, which resulted in reduced urine retention and improved micturition.  相似文献   
86.
87.
1. Diets containing 80, 100, 125, 150, 175 or 200 mg monensin/kg were fed to broiler chickens from 0 to 28 d in cages that prevented access to excreta.

2. Growth was depressed with 125 mg monensin or more/kg and food intake tended to decrease. Feathering was adversely affected with 175 mg or more/kg.

3. In a similar experiment, diets containing 8.8, 9.1, 9.4, 9.7 or 10.1 g total sulphur amino acids (SAA)/kg were supplemented with 125 or 80 mg monensin/kg and compared with a diet containing 8.8 g SAA and 33 mg robenidine/kg.

4. With 125 mg monensin/kg, body‐weight gain was significantly less than that of birds receiving robenidine if dietary SAA content was 9.4 g or less/kg. With 9.7 g SAA or more/kg, gain in birds receiving monensin was similar to that of birds receiving robenidine.

5. Monensin at 125 mg/kg therefore appears to increase the SAA requirement.  相似文献   

88.
The feeding of meat-and-bone meal (MBM) derived from cattle infected with bovine spongiform encephalopathy (BSE) is a major source of BSE infection. The risks of BSE infection via MBM in Japan were examined quantitatively to estimate infectivity to cattle via MBM derived from a single clinically infected animal being rendered. Three routes of exposure were modeled: (i) feeding cattle concentrates containing MBM as an ingredient, (ii) feeding cattle concentrates contaminated with MBM from non-ruminant feed at feed plants and (iii) directly feeding MBM in supplemental form to cattle on farms. The effectiveness of measures designed to restrict the feeding of ruminants with ruminant MBM (feed restriction) as well as differences in the risk of exposure among regions were examined using the model.

The model revealed that the median total infectivity fed to dairy cattle via MBM derived from one infected animal was approximately 0.49 cattle oral ID50 (5th percentile = 0.43 ID50, 95th percentile = 0.54 ID50). This value was reduced by 55% after the addition of MBM to cattle concentrates was restricted in 1996. The risk of exposure in dairy cattle was twice that in beef cattle. Comparisons of regional differences in exposure risk indicated that the risk was highest in a region where 14 of the 20 BSE cases reported to date were born. Our model suggested that the routes of exposure via MBM were unlikely to result in increased propagation of BSE in Japan. Furthermore, despite some regional variation, the risk of exposure declined further after the feed restriction was imposed in 1996.  相似文献   

89.
Cardiac remodeling and angiotensin II-forming enzyme activity of the left ventricle on chronic pressure overload were studied in male Syrian hamsters, whose chymase activity is similar to that of dogs. Pressure overload was achieved by banding at the ascending aorta (aortic stenosis). Echocardiography, histological analysis, and analysis of cardiac angiotensin-converting enzyme and chymase-like activities were performed. At 10 weeks after banding, concentric hypertrophy of the left ventricle was evident. At 20 weeks after banding, the ventricular weight-to-body ratio, cardiac fibrosis, and cardiac chymase-like activity were significantly increased, while cardiac angiotensin-converting enzyme activity was significantly decreased. This suggests that cardiac chymase, compared with cardiac angiotensin-converting enzyme, was activated against the chronic pressure overload and was responsible for the cardiac remodeling through the formation of angiotensin II. Considering the utility of the rodents, the interspecies similarity of the Ang II-forming pathway, and the effect of chymase in the hamsters, the present model is considered useful for studies evaluating the effect of Ang II and chymase in the canine heart with chronic pressure overload.  相似文献   
90.
Plasma proteins of wasting pigs were quantitatively and qualitatively compared with those of normal fattening pigs. Higher expression of a 120 kDa protein was observed in the plasma of wasting pigs by SDS-PAGE. This protein was identified as pig major acute-phase protein (Pig-MAP) by proteomic analysis using two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The plasma concentration of Pig-MAP in wasting pigs was 7-fold higher than that of normal ones.  相似文献   
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