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Awassi sheep and mountain goats slaughtered in northern and central Jordan were examined for Sarcocystis cysts by post-mortem examination, trichinoscopy of muscle samples taken from esophagi and diaphragms and serologically by indirect hemagglutination (IHA) during the period June 1986–May 1988. Macrosarcocysts were found in 11.3% (70/620) of sheep and 11.7% (46/393) of goats aged over 1 year old. Microsarcocysts were found in 50.1% (1185/2693) of the sheep diaphragm samples and 56.4% (711/1261) of the same organs of goats. The prevalences were lower in the esophageal muscles (26.4%, 348 of 1319 and 25.1%, 97 of 386) than the diaphragmal muscles (29.0%, 383 of 1319 and 34.2%, 132 of 386) in the younger age groups (less than 7 months) of sheep and goats, respectively. The prevalences in both the esophagus and the diaphragm increased with age. The seroprevalences of anti-Sarcocystis antibodies in sheep and goats were significantly higher (P < 0.05) than the prevalence of Sarcocystis cysts detected by trichinoscopy. The seroprevalence of sarcocystosis increased with age in sheep and goats.  相似文献   
44.
Thirty blood samples were collected randomly from each of the 38 breeder-broiler farms in Jordan. Serum samples were examined using indirect ELISA for specific antibodies to avian influenza virus. The overall true flock-level sero-prevalence of avian influenza was 71% (95% CI: 55,83). Positive flocks had 2-30 sero-positive chickens and half of flocks had >20 sero-positive birds. The number of sero-positive flocks varied in the studied localities with more sero-positives in farms located within the migratory route of migratory wild fowl. The examined broiler-breeder flocks had no clinical signs, or noticeable decrease in egg production; mortalities were within the normal range (0.1-1%). The number of positive sera/flock correlated with flock size. There were a no significant (Pearsons r=0.21, p=0.21) correlation between positive flocks and age. A non-pathogenic AI virus infects broiler-breeder farms in Jordan. Wild local and migrating birds might promote the further spread of this virus in Jordan and other countries.  相似文献   
45.
Two different biotic inducers [Pseudomonas fluorescens and Pseudomonas putida] and three different abiotic inducers [copper sulphate, indole butyric acid and potassium chloride] were tested for their efficacy in inducing resistance in lupin plants against Fusarium wilt disease caused by Fusarium oxysporum f. sp. lupini. Application of the biotic and abiotic inducers as seed treatments significantly reduced wilt disease incidence under greenhouse and field conditions. Potassium chloride and Pseudomonas fluorescens were superior. A time course of defence-related enzymes showed substantial increases in enzyme activities in induced infected seedlings compared with untreated healthy plants or infected controls. However, the magnitude of the increase varied among treatments. The maximum increases in chitinase and ??- glucanase activities were recorded at 12 and 8?days after inoculation with the pathogen, respectively. Also, the activity of phenylalanine ammonia lyase increased dramatically 8?days after inoculation. Greater accumulation of phenolic compounds and specific flavonoids upon infection with the pathogen was found in induced and/ or infected seedlings compared with healthy plants. In addition to inducing disease resistance, the treatments were accompanied by significant increases in crop parameters and seed yield compared with untreated controls.  相似文献   
46.
1. The relationship between breeder age and chick gastrointestinal tract development to 21 days of age, as influenced by immediate or delayed access to feed, was examined in three consecutive trials.

2. Ross 708 chicks, derived from breeder flocks at 31 (young), 40 (middle) and 63 (old) weeks of age were placed randomly into either a control group with immediate access to feed and water, or a 48?h feed delayed (FD) group with free access to water.

3. FD negatively affected body weight (BW) of chicks derived from young and old flocks through the first and second weeks of age, respectively. Chicks from the older flock absorbed more yolk in the first 48?h with no FD effect. When feed was made available, chicks from the FD group showed a large increase in small intestine weight relative to BW, surpassing (P? 4. Morphological measurements in all intestinal sections had higher values in chicks derived from the middle age breeder flock. FD to newly hatched chicks from the young breeder flock shortened villi (P?P? 5. Crypt depths were maximised between 7 and 14?d post-hatch in chicks from young and old breeder flocks, but crypt depths in chicks from the middle aged flocks continued to deepen.

6. The increased crypt depth may augment the number of enterocytes available for villus growth, and facilitate longer villi and greater villus surface area, in chicks from the middle age flocks. Intestinal morphological variation was associated with breeder flock age, which accounted for differential growth in chicks derived from young, middle, and old aged breeder flocks.  相似文献   
47.
Crude ethanol extracts from Ficus benjamina leaves strongly inhibit Herpes Simplex Virus 1 and 2 (HSV-1/2) as well as Varicella Zoster Virus (VZV) cell infection in vitro. Bioassay-guided fractionation of the crude extract demonstrated that the most efficient inhibition of HSV-1 and HSV-2 was obtained with the flavonoid fraction. The present study was aimed to further isolate, purify and identify substances with potent antiviral activity from the flavonoid fraction of F. benjamina extracts. Flavonoids were collected from the leaf ethanol extracts through repeated purification procedure and HPLC analysis. The antiviral activity of each substance was then evaluated in cell culture. Three known flavone glycosides, (1) quercetin 3-O-rutinoside, (2) kaempferol 3-O-rutinoside and (3) kaempferol 3-O-robinobioside, showing highest antiviral efficiency were selected and their structure was determined by spectroscopic analyses including NMR and mass spectrometry (MS). These three flavones were highly effective against HSV-1 reaching a selectivity index (SI) of 266, 100 and 666 for compound 1, 2 and 3, respectively, while the SI of their aglycons, quercetin and kaempferol amounted only in 7.1 and 3.2, respectively. Kaempferol 3-O-robinobioside showed similar SI to that of acyclovir (ACV), the standard anti-HSV drug. Although highly effective against HSV-1 and HSV-2, these flavone glycosides did not show any significant activity against VZV.  相似文献   
48.
ABSTRACT: BACKGROUND: Phloem-feeding insects are among the most devastating pests worldwide. They not only cause damage by feeding from the phloem, thereby depleting the plant from photo-assimilates, but also by vectoring viruses. Until now, the main way to prevent such problems is the frequent use of insecticides. Applying resistant varieties would be a more environmental friendly and sustainable solution. For this, resistant sources need to be identified first. Up to now there were no methods suitable for high throughput phenotyping of plant germplasm to identify sources of resistance towards phloem-feeding insects. RESULTS: In this paper we present a high throughput screening system to identify plants with an increased resistance against aphids. Its versatility is demonstrated using an Arabidopsis thaliana activation tag mutant line collection. This system consists of the green peach aphid Myzus persicae (Sulzer) and the circulative virus Turnip yellows virus (TuYV). In an initial screening, with one plant representing one mutant line, 13 virus-free mutant lines were identified by ELISA. Using seeds produced from these lines, the putative candidates were re-evaluated and characterized, resulting in nine lines with increased resistance towards the aphid. CONCLUSIONS: This M. persicae-TuYV screening system is an efficient, reliable and quick procedure to identify among thousands of mutated lines those resistant to aphids. In our study, nine mutant lines with increased resistance against the aphid were selected among 5160 mutant lines in just 5 months by one person. The system can be extended to other phloem-feeding insects and circulative viruses to identify insect resistant sources from several collections, including for example genebanks and artificially prepared mutant collections.  相似文献   
49.
Objective To evaluate the pre‐emptive analgesic effect of pre‐incisional epidural ketamine. Study Design A blinded, randomized experimental study. Animals Sixteen mixed breed mares, 7.6 ± 2.8 years old, weighing 352 ± 32 kg. Methods In a pilot study, an incision was made on one lateral thigh using a lidocaine block and no further analgesics, and it was verified that the nociceptive threshold was lower on the incised side than nonincised side (p ≤ 0.05), and that von Frey filaments evoked a pain response. The 16 animals were divided into group A (ketamine, n = 9) and B (saline, n = 7). An epidural catheter was inserted 24 hours before the trials. The thigh was shaved bilaterally, and the right side was blocked (incised side) using lidocaine. Twenty‐five minutes later, ketamine (A) or saline (B) was administered epidurally. Five minutes later, a 10‐cm skin incision was made on the right side, and then sutured. Nociceptive threshold was determined with von Frey filaments at 1, 3, and 5 cm around the incision at 15‐minute intervals for 2 hours, then at 4, 6, and 8 hours. Behavioral alterations, heart and respiratory rates were recorded. Nociceptive thresholds from these points were averaged to obtain mean values at each time, converted to a logarithmic scale, and submitted to a nonparametric analysis (Mann–Whitney and one‐way repeated measures anova test, p ≤ 0.05). Results After 8 hours, the global range score revealed reduced hyperalgesia (p < 0.01) around the incision in 92% (4.65–4.27) of evaluated intervals in group A (ketamine). There were no significant changes in behavior, heart and respiratory rates. Conclusions It was concluded that pre‐emptive epidural ketamine reduced post‐incisional pain in the horse, and that von Frey filaments were able to quantify cutaneous sensitivity after tissue damage. Clinical relevance Epidural ketamine injection can reduce post‐incisional sensitivity in the horse.  相似文献   
50.
Bee pollen (BP) is one of the most useful therapeutic products favoured by natural medicine scientists because of its possible nutritional and medical applications. It exhibits many impacts such as antimicrobial, immunostimulating, antioxidants and hepatoprotective. Furthermore, BP has some useful therapeutic features in numerous pathological situations such as its impact to normalize wound healing. Based on previous literatures, the level of BP supplement in livestock and poultry ranged from 0.1 to 20 g/kg diet. This variation depends on the species, physiological status, age and purpose of addition; so far generally, it accepted to use the level with no side effects. It has been observed that BP enhanced growth performance, immunity responses and blood variables and had hypoglycaemic activity by reducing the lipid in the blood and carcass. Also, BP contains more nutrients, which stimulate faster differentiation and proliferation of the cells of immune system of birds. Therefore, the present review recommends that BP supplementation (up to 20 g/kg diet) had possible beneficial impacts, antioxidants and protective activities on most of the production, productive and health patterns of livestock.  相似文献   
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