水产饲料中的霉菌霉素     

Pedro Encarno 《饲料工业》2010,31(16)

霉菌毒素是霉菌产生的次级代谢产物.霉菌在农作物收获前、收获后及运输和仓储的过程中都可生长并产生霉菌毒素.  相似文献   

Effect of glyphosate on the tripartite symbiosis formed by Glomus intraradices,Bradyrhizobium japonicum,and genetically modified soybean     

Jeff R. Powell  Rachel G. Campbell  Kari E. Dunfield  Robert H. Gulden  Miranda M. Hart  David J. Levy-Booth  John N. Klironomos  K. Peter Pauls  Clarence J. Swanton  Jack T. Trevors  Pedro M. Antunes 《Applied soil ecology》2009,41(1):128-136

Most soybeans grown in North America are genetically modified (GM) to tolerate applications of the broad-spectrum herbicide glyphosate; as a result, glyphosate is now extensively used in soybean cropping systems. Soybean roots form both arbuscular mycorrhizal (AM) and rhizobial symbioses. In addition to individually improving host plant fitness, these symbioses also interact to influence the functioning of each symbiosis, thereby establishing a tripartite symbiosis. The objectives of this study were to (1) estimate the effects of glyphosate on the establishment and functioning of AM and rhizobial symbioses with GM soybean, and (2) to estimate the interdependence of the symbioses in determining the response of each symbiosis to glyphosate. These objectives were addressed in two experiments; the first investigated the importance of the timing of glyphosate application in determining the responses of the symbionts and the second varied the rate of glyphosate application. Glyphosate applied at recommended field rates had no effect on Glomus intraradices or Bradyrhizobium japonicum colonization of soybean roots, or on soybean foliar tissue [P]. N₂-fixation was greater for glyphosate-treated soybean plants than for untreated-plants in both experiments, but only when glyphosate was applied at the first trifoliate soybean growth stage. These data deviate from previous studies estimating the effect of glyphosate on the rhizobial symbiosis, some of which observed negative effects on rhizobial colonization and/or N₂-fixation. We did observe evidence of the response of one symbiont (stimulation of N₂-fixation following glyphosate) being dependent on co-inoculation with the other; however, this interactive response appeared to be contextually dependent as it was not consistent between experiments. Future research needs to consider the role of environmental factors and other biota when evaluating rhizobial responses to herbicide applications.  相似文献   

Effect of the fungicide imazalil on hepatic microsomal cytochrome P-450 and cytochrome P-450 dependent activities in the Bobwhite quail (Colinus virginianus)     

Karel Lavrijsen  Jos Van Houdt  Dirk Van Dyck  Willem Meuldermans  Jos Heykants 《Pest management science》1990,29(1):47-56

Bobwhite quails were treated with imazalil for 8 weeks. The fungicide was given admixed in the food at 0, 100, 300, 500 and 1000 mg kg^?1. Even at the highest dose tested, imazalil did not affect the liver weight or the hepatic microsomal protein content. In treated quails, no significant induction of cytochrome P-450 or NADPH-cytochrome c-reductase activity was observed. Furthermore, imazalil did not induce or inhibit 7-ethoxyresorufin or 7-ethoxycoumarin O-deethylase in quail microsomes. Only a slight but significant increase by 35% and 49% in aniline hydroxylase activity was measured for the 500- and 1000-mg kg^?1 dose levels, respectively. After a drug-free period of one week, aniline hydroxylase activity returned to control values, indicating that the effect was fully reversible. It is concluded that imazalil does not induce or inhibit drug-metabolizing enzymes in the quail, even at doses which exceed by far the maximum levels currently used to dress seed under field conditions (100 mg kg^?1).  相似文献   

New mite-borne virus isolates from rakkyo,shallot and wild leek species   总被引：2，自引：0，他引：2  

Paul van Dijk  René A. A. van der Vlugt 《European journal of plant pathology / European Foundation for Plant Pathology》1994,100(3-4):269-277

Flexuous viruses were transmitted from rakkyo (Allium chinense) and wild leek species (especiallyA. commutatum) to plants of crow garlic (A. vineale), by transfer of dry bulb mites. By electron microscope decoration tests using three antisera and by inoculations onto test plants, it was concluded that from each of the two natural host species at least two viruses were isolated. The viruses from wild leeks are both pathogenic onAllium spp. and may be of economic importance. Decoration tests on a virus mixture from shallot obtained earlier, revealed another new mite-borne virus in this species. The mite-borne viruses ofAllium spp. appear to be very common; they are largely diverse and their identification remains difficult.  相似文献   

Modelling the microbial breakdown of pesticides in soil using a parameter estimation technique     

Jos P. M. Vink  Peter Nrtersheuser  Otto Richter  Bernd Diekkrüger  Klaas P. Groen 《Pest management science》1994,40(4):285-292

Results of field measurements and laboratory experiments were used to simulate the behaviour of 1,3-dichloropropene (1,3-D) in a loamy sand soil. Microbial activity was described using pre-set conditions to compute transformation rates as dependent on compound concentrations and temperature. These kinetics could only be analysed using non-linear transformation rates. To link the development of microbial populations and the consumption of the compound over time, an iterative technique was used to estimate the necessary parameters.  相似文献   

Reduction of diameter of the left ventricle of dogs by plication of the left ventricular free wall     

de Andrade JN  Wouk AF  Camacho AA  de Lourdes Branco Germiniani C  Gavazzoni L 《American journal of veterinary research》2001,62(3):297-300

OBJECTIVE: To determine effects of reducing the diameter of the left ventricle of dogs by plication of the left ventricular free wall. ANIMALS: 8 healthy adult mixed-breed dogs. PROCEDURE: Left lateral thoracotomy and a T-shaped pericardiotomy were performed. The free wall of the left ventricle was imbricated with 3 interrupted transfixing sutures applied in a horizontal mattress pattern, using 3-0 polypropylene suture assembled on a straight cutting needle. Surgeons were careful to avoid the coronary vessels. Echocardiography was performed 24 hours before and 48 hours after surgery. Electrocardiography was performed before and 1, 2, 7, 15, 21, 30, and 60 days after surgery. RESULTS: Echocardiographic measurements revealed that the diameter of the left ventricle was reduced by a mean of 23.5%. Electrocardiography revealed ventricular premature complexes 24 hours after surgery that regressed without treatment during the first week after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Plication of the left ventricular free wall of dogs can reduce end-diastolic and end-systolic dimensions of the left ventricle. The technique is simple and does not require cardiopulmonary bypass. According to Laplace's law, the reduction of cardiac diameter leads to reduction on free-wall tension and may improve left ventricular function in dilatated hearts. Thus, additional studies involving dogs with dilated cardiomyopathy should be conducted.  相似文献   

Crude protein fractions in common vetch (Vicia sativa L.) fresh forage during pod filling     

Alzueta C  Caballero R  Rebolé A  Treviño J  Gil A 《Journal of animal science》2001,79(9):2449-2455

Crude protein (CP) of forages can be separated into fractions of differentiated abilities to provide available amino acids in the lower gut of ruminants. This knowledge is critical to develop feeding systems and to predict animal responses. We have measured during two growing seasons (1996 to 1997 and 1997 to 1998) the CP fractions of common vetch fresh forage with the objective being to assess the influence of maturity on concentration of CP fractions (as a percentage of total CP) and fraction yields. Fraction B2, which represents true protein of intermediate ruminal degradation rate, was the largest single fraction in common vetch forage (about 40% of CP across seasons and maturity stages). Soluble fractions (A plus B1) were less than 50% of total CP while the unavailable fraction C ranged from 4 to 8% of total CP. As a result, the remaining fraction B3 (true protein of very low degradation rate) only represented 2 to 9% of total CP. Concentration and yield of fraction B3 increased (P < 0.05) from flowering to pod-filling. Results showed that undegraded dietary protein represented a small proportion of total CP in common vetch forage. Moving the harvesting stage from flowering to the pod filling phase allowed for greater yield of undegraded dietary protein.  相似文献   

Disease and mortality on red deer farms in New Zealand     

Audigé L  Wilson PR  Morris RS 《The Veterinary record》2001,148(11):334-340

A longitudinal observational study of 15 red deer farms was carried out in New Zealand for two years from March 1992. The deer were monitored for performance and health problems, and farm management practices were recorded. Numbers at risk were 4,683 hind-years, 2,459 stag-years and 3,202 weaner-years. The numbers of primiparous and adult hinds at risk of losing their progeny by weaning were 653 and 3,364, respectively. Where possible, postmortem examinations were carried out, and organs were sampled for histological and microbiological investigation. Rates of mortality varied with season with most stag and hind deaths in winter and weaner deaths in autumn and winter. Overall mortality rates were 1.77, 2.60 and 5.87 per 100 deer-years for hinds, stags and weaners, respectively. Malignant catarrhal fever accounted for 0.53 stag and 0.17 hind deaths per 100 deer-years at risk Misadventure, including broken bones, accounted for 15.4 per cent of weaner mortalities, or 0.53 weaner mortalities per 100 weaner-three months in autumn. Yersiniosis was confirmed in 18.6 per cent of weaner deaths, or 1.09 weaners per 100 weaner-years during the first six months after weaning, but was also suspected but unconfirmed in a further 41 per cent of weaner mortalities. Overall, 17 per cent of yearling hinds, and 9.2 per cent of adult hinds lost their progeny between pregnancy diagnosis in June and weaning in March. One outbreak of osteochondrosis was recorded. Mortality rates varied between farms and many mortalities were preventable.  相似文献   

Open reduction of sacral fractures using transarticular implants at the articular facets of L7-S1: 8 consecutive canine patients (1995-1999)     

Paré B  Gendreau CL  Robbins MA 《Veterinary surgery : VS》2001,30(5):476-481

OBJECTIVE: To describe and evaluate facet stabilization as an aid for open reduction and fixation of sacral fractures. STUDY DESIGN: A clinical case series. STUDY POPULATION: Eight consecutive client-owned dogs with sacral fractures. METHODS: A combination of a standard lateral approach to the ilium and a dorsal approach to the articular facets of L7-S1 was performed. The articular facets were reduced and stabilized with a Kirschner wire or a combination of a Kirschner wire and a cortical screw. Primary stabilization of the sacrum was then accomplished using a cortical screw inserted from the lateral aspect of the ilium, through the sacral fracture into the body of the sacrum. Accuracy of reduction, position of the implants, percent screw depth/sacral width, pelvic canal diameter ratio, and complications were assessed using radiographs and physical examination. RESULTS: Mean sacral fracture reduction was 91% immediately after surgery, and was 87% when measured at follow-up examinations. Mean screw depth/sacral width was 66%. Mean pelvic canal diameter ratio was 1.12 postoperatively and 1.03 at the 4- to 6-week reevaluation. Six of the 8 dogs were using the leg well 10 to 12 days after surgery; none had clinically detectable neurologic deficits. The long-term (mean, 2.7 years) outcome for these dogs was good (normal to grade I lameness). CONCLUSION: Fixation of the L7-S1 facet joints facilitates repair of sacral fractures.  相似文献   

Validation of a polymerase chain reaction assay for monitoring the therapeutic efficacy of diminazene aceturate in trypanosome-infected sheep     

Bengaly Z  Kasbari M  Desquesnes M  Sidibé I 《Veterinary parasitology》2001,96(2):101-113

The diagnostic performance of a polymerase chain reaction assay (PCR) for monitoring the effectiveness of aceturate diminazene treatment was compared with those of an antibody-detection ELISA test and the buffy-coat technique using sheep experimentally infected with either savannah-type or forest-type Trypanosoma congolense or T. vivax. Within the period of infection, the PCR using specific savannah-type T. congolense primers showed a significant higher diagnostic sensitivity (p<0.05) than the buffy-coat technique. Both techniques gave closed results for detecting forest-type T. congolense or T. vivax infections. Following trypanocidal treatment, the PCR showed that specific product disappeared definitively 1 or 2 days later in animals in which a decrease of the antibody level and a significant improvement of the red packed cell volume were observed. The occurrence of relapse infection was detected by the PCR in one animal infected by T. vivax on day 19 post-treatment and confirmed by the persistence and increasing antibody level whereas the buffy-coat technique detected parasites 42 days later. Then, the PCR signals remained positive on several occasions while parasitaemia was detected only two times.The application of PCR combined with the antibody detection appeared to provide a useful tool as compared to the buffy-coat technique for monitoring the effectiveness of trypanocidal treatment.  相似文献