A 12-month survey of the gastro-intestinal helminths of antelopes, gazelles and giraffids kept at two zoos in Belgium

Faecal egg count patterns and clinical signs associated with gastro-intestinal (GI) nematodes of 107 zoo ruminants were monitored at fortnightly intervals for 1 year. The ruminants in this study were kept under different husbandry conditions at two sites of the Royal Zoological Society of Antwerp, the Antwerp Zoo and the Animal Park Planckendael. Artiodactylids involved were Arabian oryx (Oryx leucoryx), scimitar-horned oryx (Oryx dammah), bongos (Tragelaphus euryceros isaaci), sitatungas (Tragelaphus spekii gratus), common eland (Taurotragus oryx), impala (Aepyceros melampus), slender-horned gazelles, (Gazella leptoceros), blue wildebeest (Connochaetes taurinus taurinus), Kordofan giraffes (Giraffe camelopardalis antiquorum) and okapi (Okapia johnstoni). Nematode eggs were recovered from 586 of 1606 (36.5%) individual faecal samples, using flotation techniques. Infection levels were distinctly low at Antwerp Zoo, probably due to zero grazing and daily dung removal. At Planckendael, the herds of Arabian oryx, scimitar-horned oryx and slender-horned gazelles showed markedly higher egg counts than the other herds, with more than 10% of the faecal egg counts having more than 100 eggs per gram (epg) and maximum faecal egg counts of 600, 750 and 1350 epg, respectively. Faecal egg counts increased during the mid-grazing season (July) and peaked at the end of the grazing season (October). No clinical signs, such as loss of faecal consistency, could be correlated with faecal egg counts (P > 0.05). With the exception of significantly more Nematodirus spp. eggs that were present in juvenile eland, no differences in faecal egg counts could be found between the sexes and different age groups. Abomasa and intestines of 17 animals that died during the survey were available for total worm counts. In one Arabian oryx, four slender-horned gazelles and one sitatunga low burdens ranging from 200 to 14,300 were found. Nematode species recovered were Camelostrongylus mentulatus from the abomasa and Trichostrongylus retortaeformis, Nematodirus fillicollis, Capillaria spp. and Trichuris spp. from the intestines. Our findings suggest different nematode infection levels between herds, which are mainly due to husbandry conditions but to a lesser extent to species- or individual susceptibility. Identification of ungulates that are highly infected and knowledge of the seasonal variation of their helminths can contribute greatly to a well-adjusted species-specific management and helminth control program.     

Comparison of the effects of caudal pole hemi-meniscectomy and complete medial meniscectomy in the canine stifle joint

OBJECTIVE: To compare the effects of caudal pole hemi-meniscectomy (CPHM) and complete medial meniscectomy (MM), specifically with respect to development of secondary osteoarthritis, in the stifle joints of clinically normal dogs. ANIMALS: 14 large-breed dogs. PROCEDURE: Unilateral CPHM (7 dogs) or MM (7) was performed, and the left stifle joints served as untreated control joints. Gait was assessed in all dogs before surgery and at 4, 8, 12, and 16 weeks postoperatively. After euthanasia, joints were evaluated grossly; Mankin cartilage scores, subchondral bone density assessment, and articular cartilage proteoglycan extraction and western blot analyses of 3B3(-) and 7D4 epitopes were performed. RESULTS: Weight distribution on control limbs exceeded that of treated limbs at 4 and 16 weeks after surgery in the CPHM group and at 4 and 8 weeks after surgery in the MM group; weight distribution was not significantly different between the 2 groups. After 16 weeks, incomplete meniscal regeneration and cartilage fibrillation on the medial aspect of the tibial plateau and medial femoral condyle were detected in treated joints in both groups. Mankin cartilage scores, subchondral bone density, and immunoexpression of 3B3(-) or 7D4 in articular cartilage in CPHM- or MM-treated joints were similar; 7D4 epitope concentration in synovial fluid was significantly greater in the MM-treated joints than in CPHM-treated joints. CONCLUSIONS AND CLINICAL RELEVANCE: Overall severity of secondary osteoarthritis induced by CPHM and MM was similar. Investigation of 7D4 epitope concentration in synovial fluid suggested that CPHM was associated with less disruption of chondrocyte metabolism.     

Detection of pathogenic Listeria spp. in zoo animal faeces: use of immunomagnetic separation and a chromogenic isolation medium

Faecal samples, collected from 200 healthy animals in Antwerp Zoo, were examined for the presence of pathogenic Listeria spp. A two-stage standard isolation (ISO) method was combined with immunomagnetic separation (IMS). ALOA agar, a chromogenic isolation medium, differentiating Listeria spp. on the basis of beta-glucosidase and phosphatidylinositol-specific phospholipase C (PIPLC) activity, was compared with PALCAM agar. Confirmation of the isolates was based on conventional biochemical tests and a disc test, which detects a specific aminopeptidase produced by all Listeria spp. except Listeria monocytogenes. Listeria spp. were isolated from 42 (21.0%), L. monocytogenes from 14 (7.0%), and Listeria ivanovii from two (1.0%) faecal samples. The application of IMS after primary enrichment detected pathogenic Listeria spp. in 12 (6.0%) samples. The ISO method, combining primary and secondary enrichment, detected pathogenic Listeria spp. in 15 (7.5%) samples. The sensitivity of IMS compared to the ISO method was 73.3% and the specificity was 99.5%. ALOA agar was superior to PALCAM agar for isolation of Listeria spp. The disc test identified all L. monocytogenes isolates. IMS after primary enrichment was a suitable screening method, but secondary enrichment increased the number of positive samples.     

A comprehensive study of Easter lily poisoning in cats.

This study was conducted with 3 objectives in mind: first, to identify the toxic fraction (aqueous or organic) in leaves and flowers; second, to identify diagnostic marker(s) of toxicosis in cats; and, third, to evaluate the morphologic effects of intoxication. The study was conducted in 2 phases. Phase 1 was to identify which extract, organic or aqueous, was nephrotoxic and also to determine the appropriate dose for use in the phase 2 studies. Results indicated that only the aqueous extracts of leaves and flowers were nephrotoxic and pancreotoxic. To identify the proximate toxic compound, cats in the phase 2 study were orally exposed to subfractions of the aqueous flower extract, 1 subfraction per cat. Results confirmed vomiting, depression, polyuria, polydipsia, azotemia, glucosuria, proteinuria, and isosthenuria as toxic effects of the Easter lily plant. Another significant finding in serum was elevated creatinine kinase. Significant histologic kidney changes included acute necrosis of proximal convoluted tubules and degeneration of pancreatic acinar cells. Renal ultrastructural changes included swollen mitochondria, megamitochondria, edema, and lipidosis. Subfraction IIa3 of the aqueous floral extract contained most of the toxic compound(s). These studies reproduced the clinical disease, identified the most toxic fraction of the Easter lily, and helped characterize the clinical pathology, histopathology, and ultrastructural pathology associated with the disease.     

Genome-based PCR Primers for Specific and Sensitive Detection and Quantification of Xylella fastidiosa

Xylella fastidiosa is an important pathogen of many commercial crops. Detection of X. fastidiosa is difficult due to low concentrations of the bacteria in insects and asymptomatic plant tissue, and non-uniform distribution in infected plants. A dual purpose conventional PCR and quantitative PCR (TaqMan™) system was developed for the generic detection of X. fastidiosa strains. Primers HL5 and HL6, designed to amplify a unique region common to the sequenced genomes of four Xylella strains, amplified a 221 bp fragment from strains associated with Pierce’s disease of grapes, almond leaf scorch, and oleander leaf scorch disease and from DNA from an Xf strain associated with citrus variegated chlorosis. Standard curves were obtained using concentrations of Xylella ranging from 5 to 10⁵ cells per reaction in water and grape extracts and 10–10⁵ cells in insect DNA. Regression curves were similar, with correlation coefficients of r ² > 0.97. In quantitative PCR, C_t values ranged between 20 and 36 cycles for 5–10⁵ bacterial cells per reaction. No amplicons were obtained with several non-Xf bacterial strains tested including related plant pathogenic, grape endophytic bacteria and endosymbiotic bacteria isolated from glassy-winged sharpshooters. The method was evaluated for clinical diagnosis of Xf in grapes, almonds and insect vectors. The procedure described is reliable for detection of the pathogen with a high degree of sensitivity and specificity.     

Effects of exercise on canine skeletal muscle proteolysis: an investigation of the ubiquitin-proteasome pathway and other metabolic markers

The effects of long-term athletic training are associated with excessive skeletal muscle turnover attributable to increased rates of myofibrillar protein synthesis and proteolysis, which are mechanisms poorly understood in the athletic dog. A physiologic field study using 44 English pointers and Labrador retrievers that had been purposely bred for bird hunting and retrieving was conducted to examine changes in the ubiquitin-proteasome (UP) pathway, which has been implicated in exercise-induced proteolysis. Muscle biopsy samples were collected from all dogs in September (preseason, pretraining) and February (peak season, peak activity). Western blot analysis was used to assess changes in expression of various components of the UP pathway in the biopsy samples. Citrate synthase and glycogen levels were also measured in a subset of these samples. Results across the population indicated pronounced up-regulation of ubiquitinated conjugates and the p31 regulatory capping subunit during the peak hunting period compared with the preseason period. In contrast, the catalytic core of the proteasome (beta-subunits) showed no apparent up-regulation in response to increased physical activity. Increased physical activity during the hunting season was associated with increased muscle glycogen levels and citrate synthase activity in these dogs. Overall, up-regulation of specific components of the UP pathway was an indication that it plays a role in the proteolytic process associated with skeletal muscle turnover during long-term athletic training, as previously believed.     

通过种间杂交选育加工黄瓜新品种宁佳1号

以黄瓜属(Cucumis)野生种(C. hystrixChakr. )为母本,以栽培黄瓜(C. sativusL. )北京截头为父本,通过远缘杂交导入外源种质,结合多代回交、自交获得黄瓜新种质7012A。将7012A与美国威斯康辛大学选育的雌性系黄瓜(7011A)杂交获得F1,与亲本及美国推广加工黄瓜品种进行品种比较试验,结果表明:F1 具有超亲优势,结瓜整齐,营养价值高,加工品质良好。植株长势强,主侧蔓均有结瓜能力,主蔓结瓜为主,后期产量高。     

Stickstoffumsatz in einer Lößcatena

Nitrogen turnover in a loess catena N-mineralization and mineral-N-contents were determined from spring 1993 to autumn 1995 on arable soils from loess (Luvisol, Calcaric Regosol, Gleyic-Calcaric Regosol and Cumulic Anthrosol) of a catchment area called “Bonartshäuser” farm near Gondelsheim in western Kraichgau (SW-Germany). The aim was to find out, whether the course of net-N-mineralization and mineral-N-content of the soil could be explained by the parameters soil temperature and soil moisture. Soil samples were incubated in polyethylene bags on site for mineralization and aliquots analyzed in the laboratory for the determination of the mineral-N-content. In 1993, 55 kg N ha^—1 were immobilized and up to 170 kg N ha^—1 mineralized depending on the soil type. In 1994, between 181 and 297, and in 1994, between 59 and 230 kg N ha^—1 were mineralized annually. Mineral-N-contents of the different soils throughout the experimental period (n = 45) were found to correlate much better (r² between 0.55 and 0.86) whereas net-N-mineralization (n = 44) showed coefficients of determination (r²) just between 0.08 and 0.53. Except for the Luvisol (37%) only 0 to 8% of net-N-mineralization could be explained by the combined effect of mean soil temperature and soil moisture at the beginning of the incubation using multiple linear regression analysis. Merely 1 up to 9% of mineral-N-content of the soil could be explained by the same effect. The variability and inconsistency shown by net-N-mineralization renders it inappropriate as a tool for predicting nitrogen delivery of the soil and basis for setting rules governing permissible nitrogen amounts in the soil.