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61.
消化道疾病往往导致养猪生产中相当大的经济损失,尽管最初的症状只是粪便黏稠不成形.一方面可能是致病性因素改变了猪消化道环境,使机体变得虚弱;另一方面,当育成猪受到腹泻影响时,应该考虑到还有很多可能的原因.  相似文献   
62.
The aims of this study were to analyze the influence of systematic environmental effects on the prevalence of primary non-congenital cataract (CAT), fibreglass cataract in the nucleus (FCN), and prominent suture lines (PSL) and to estimate the heritabilities of these eye diseases in the wild-boar-colored wirehaired Dachshunds (WWD) bred in the German Dachshund Club 1888 e.V. (DTK). Data included 2,430 WWD born between 1995 and 2003 that were examined between 1996 and 2005 by veterinary ophthalmologists. CAT was diagnosed in 3.83% of the 2,430 dogs, FCN in 3.74%, and PSL in 2.76%. Sex, size, inbreeding coefficient, the age of the dog at examination, experience of the veterinary ophthalmologist and the additive genetic effect of the animal were considered in the multivariate linear model. The age of the dog at examination had a significant influence on the prevalence of FCN. The degree of experience of the veterinary ophthalmologist significantly influenced the prevalence of FCN and PSL. Using a transformation into the Dempster-Lerner threshold model, heritability estimates (h(DL)2) for WWD were h(DL)2 = 0.39 +/- 0.13 for CAT, h(DL)2 = 0.36 +/- 0.11 for FCN and h(DL)2 = 0.49 +/- 0.12 for PSL. Positive genetic correlations (r(g)) were found between CAT and FCN (r(g) = 0.58 +/- 0.21), between PSL and FCN (r(g) = 0.83 +/- 0.23), and between CAT and PSL (r(g) = 0.79 +/- 0.06). The eye diseases investigated here in the Dachshund were found to be genetically influenced and positively correlated traits.  相似文献   
63.

Background

Neoplasia may cause hypoglycemia in different species including the horse, but hypoglycemia has not previously been reported in the horse associated with gastrointestinal stromal tumours.

Case presentation

A case of a gastrointestinal stromal tumour in a Fjord pony with severe recurrent hypoglycemia is presented. The mechanism causing the hypoglycemia was not established.

Conclusion

This case indicates that a gastrointestinal stromal tumour may cause hypoglycemia also in the horse.  相似文献   
64.
Between 2002 and 2006, a large number of juvenile northern goshawks (Accipiter gentilis) with central nervous signs were examined. They were aged between 45 and 55 days and had been fed on frozen and thawed day-old chicks. High-performance liquid chromatography showed that the birds had whole blood thiamine levels between 2.2 and 6.0 microg/l; the concentrations of other blood constituents were within their reference ranges. Treatment with thiamine hydrochloride rapidly resolved the clinical signs. Measurements of the concentration of thiamine in 22 free-ranging and captive goshawks showed that they ranged from 45.1 to 200 microg/l.  相似文献   
65.
66.
Organophosphorothioates and synergised synthetic pyrethroids were used in duplicate field trials carried out on bulk wheat in commercial silos in Queensland and New South Wales. Laboratory bioassays using malathion-resistant strains of insects were carried out on samples of treated grain at intervals over 9 months. These established that all treatments were generally effective. Deltamethrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1), fenitrothion (12 mg kg?1)+ fenvalerate (1 mg kg?1)+ piperonyl butoxide (8 mg kg?1), fenitrothion (12 mg kg?1)+ phenothrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1) and pirimiphos-methyl (4 mg kg?1)+ permethrin (1 mg kg?1)+ piperonyl butoxide (8 mg kg?1) controlled common field strains of Sitophilus oryzae (L.) and Rhyzopertha dominica (F.). Against a highly resistant strain of S. oryzae, deltamethrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1) was superior to the remaining treatments. All treatment combinations completely prevented progeny production in Tribolium castaneum (Herbst), T. confusum Jacquelin du Val and in Ephestia cautella (Walker). Residues of deltamethrin, fenvalerate, permethrin and phenothrin were determined and shown to be highly persistent on stored wheat. During milling, residues accumulated in the bran fractions and were reduced in white flour. They were not significantly reduced during baking.  相似文献   
67.
Over the past few years the number of biogas slurries, which are generally used as nitrogen fertilisers, have seen a steady increase in Germany. A mechanistic ammonia volatilisation model was developed to predict the ammonia losses of these slurries when applied to bare soil, maize, wheat and rye grass canopies. Data for model development were collected from several field measurements carried out at two locations in Northern Germany between the years of 2007 and 2008. Additionally, the behaviour of the slurries on and in the soil was investigated through the use of infiltration pot experiments. The model includes three main compartments: slurry, atmosphere and soil. The soil compartment model is relatively simple, as the slurry infiltration, nitrification and ploughing dislocation into the soil determined in the experiments showed quantitatively no significant differences between the tested slurries (mono-fermented, co-fermented and pig slurry) and soils (sand soil and loamy sand). Hence, instead of a complex soil model, stable reduction factors, as derived from the experiments, were implemented in the model. Simulated ammonia emissions were statistically compared (root mean square error (RMSE), modelling efficiency (ME), linear regression) to the observed emissions. All evaluations showed an acceptable model performance (RMSE = 1.80 kg N ha−1), although there were a few number of anomalies which could not be modelled in an adequate way. A model sensitivity analysis showed that temperature and slurry pH value are the main drivers of NH3 volatilization in the model. Following a change of +1°C or of +0.1 pH unit ammonia volatilization will increase by about 1% and 1.6% of the applied total ammoniacal nitrogen, respectively. We were able to show that a simple model approach could explain most factors of ammonia volatilization in biogas crop rotations.  相似文献   
68.
Yersinia ruckeri produces an antibacterial factor which inhibits the growth of a wide spectrum of Gram-negative and Gram-positive bacteria, though not other strains of Y. ruckeri. The antibacterial factor was produced at low temperatures (4-20 degrees C), but not at 37 degrees C. The activity was lost after treatment of the supernatant with chloroform, UV-light and after boiling of the supernatant. One did not succeed in obtaining the antibacterial factor in a sterile solution.  相似文献   
69.
The development of a bovine monoclonal antibody against Brucella abortus smooth lipopolysaccharide (BM-8) by interspecies fusion of bovine peripheral lymphocytes from an immunized cow and a murine plasmacytoma cell line is described. The twice cloned cell line secreted bovine IgG1 subclass antibody. Ascites fluid was prepared in pristane treated nu/nu mice by intraperitoneal injection. The pooled ascites fluid was purified by affinity chromatography and the functions of the antibody assessed in various serological tests. The BM-8 antibody did not agglutinate well at a neutral pH, however, under acid conditions it was efficient at agglutinating B. abortus cells. The antibody did not precipitate B. abortus LPS in double agar gel immunodiffusion but was very active in the direct complement fixation test and the indirect enzyme immunoassay, although it was unable to compete with a murine monoclonal antibody in a competitive enzyme immunoassay.  相似文献   
70.
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