Pathology of infectious diarrhea of infant rats (IDIR) induced by an antigenically distinct rotavirus     

A C Huber  R H Yolken  L C Mader  J D Strandberg  S L Vonderfecht 《Veterinary pathology》1989,26(5):376-385

Suckling rats were inoculated with a group B rotavirus to determine the progression of the morphologic changes induced in the intestine by this virus. Several changes were observed by light microscopy 1 day after viral inoculation: shortening of small intestinal villi, villous epithelial necrosis, and villous epithelial syncytia. The lesions were most often present in the distal small intestine, although other small intestinal segments were affected to a lesser degree. By day 3 post-inoculation, epithelial necrosis, and syncytia were no longer present; however, the villous epithelium was disorganized and irregularly vacuolated, and intestinal crypt epithelium was hyperplastic. Alterations in villous height to crypt depth ratios were present in portions of the small intestine for the remainder of the 12-day study period. Epithelial syncytia appeared to form by the breakdown of the lateral interdigitating membranes of the absorptive villous epithelium. Viral particles, abundant in the syncytia, appeared to form from amorphous or reticular arrays of viral precursor material. Group B rotaviral antigens, as detected by indirect immunofluorescence, were present in large amounts in the small intestinal villous epithelium only on the first day after viral inoculation. These studies show that two important diagnostic features of group B rotaviral infections of rats, epithelial syncytia and viral antigen as determined by immunofluorescence, are present only on the first day of disease. These findings should be taken into consideration when attempting to diagnose disease induced by this agent.  相似文献   

One-generation divergent selection on large and small yolk proportions in a White Leghorn line   总被引：1，自引：1，他引：0  

Hartmann C  Johansson K  Strandberg E  Wilhelmson M 《British poultry science》2000,41(3):280-286

1. A striking change in egg consumption from shell eggs toward egg products is taking place. Consequently, internal egg quality traits must be seen in a different light, as they may affect the profitability of the egg processing industry. In order to study the possibility of using breeding as a means to alter yolk production, a one-generation divergent selection experiment was set up. The trait was yolk proportion. The effect of hen's age on egg composition was also studied. Genetic parameters for yolk proportion, yolk weight, egg weight and albumen weight were estimated, using a multiple trait animal model, and restricted maximum likelihood. 2. Selection response was obtained for yolk proportion and correlated selection responses for yolk weight and albumen weight. In the 'high line' a decrease in egg weight and an increase in yolk weight was established, whereas in the 'low line', egg weight remained more or less the same and yolk weight decreased slightly 3. Yolk proportion, yolk weight, egg weight and albumen weight all increased with increasing age of the hen in both selection lines. The difference between selection lines in yolk proportion, yolk weight and albumen weight persisted throughout the laying period. 4. Estimated heritabilities for yolk proportion, yolk weight, egg weight and albumen weight were 0.38, 0.22, 0.34 and 0.41 respectively. The genetic correlation between yolk proportion and yolk weight was 0.52, whereas the genetic correlations with egg weight and albumen weight were -0.51 and -0.74 respectively. 5. We conclude that selection can be used to alter yolk production. Selection can be at an early age with a sustained effect throughout the laying period.  相似文献   

Simple diagnosis of ectomycorrhiza formation and demonstration of the architecture of the Hartig net by means of a clearing technique     

J.-E. Nylund  Asa Kasimir  Agneta Strandberg Arveby  T. Unestam 《Forest Pathology》1982,12(2):103-107

Coniferous ectomycorrhiza was cleared in KOH and bleached in H₂ 0₂ . After the treatment, the structure of the Hartig net and inner mantle could be studied in detail in entire mycorrhizal short roots. The Hartig net and inner mantle were found to be formed by the same type of labyrinthic tissue, a result of morphogenetic processes during mycorrhiza formation. Even early phases of mycorrhizal infection could easily be detected, which makes the method very suitable for diagnosticating mycorrhiza formation accurately.  相似文献   

Atelectasis causes gas exchange impairment in the anaesthetised horse   总被引：4，自引：0，他引：4  

G Nyman  B Funkquist  C Kvart  C Frostell  L Tokics  A Strandberg  H Lundquist  B Lundh  B Brismar  G Hedenstierna 《Equine veterinary journal》1990,22(5):317-324

The anatomical basis of gas exchange impairment in the anaesthetised horse was studied by computerised tomography (CT; three shetland ponies) and morphological analysis (one pony and three horses). By means of CT, densities were seen in dependent lung regions early during anaesthesia, both with spontaneous breathing and with mechanical ventilation. The densities remained for some time where they had initially been created when the animal was turned from dorsal to sternal recumbency. Deep insufflation of the lungs reduced the dense area. Gas exchange was impaired roughly in proportion to the dense area. On histological analysis, the densities were atelectatic and congested with blood. Gravimetry showed no more extravascular water per unit lung tissue in the atelectatic than in the 'normal' regions, and the blood content was increased only slightly. It is concluded that the horse develops atelectasis in dependent lung regions early during anaesthesia in dorsal recumbency, and that atelectasis is the most likely explanation for the large shunt and impaired arterial oxygenation regularly seen during anaesthesia.  相似文献   

Kinetic study of serum gentamicin concentrations in baboons after single-dose administration     

J R Watson  M K Stoskopf  H Rozmiarek  J D Strandberg 《American journal of veterinary research》1991,52(8):1285-1287

This study establishes preliminary pharmacokinetic data on the use of gentamicin sulfate administered IM to baboons. Serum concentrations greater than or equal to 12 micrograms/ml are generally agreed to cause toxicosis in human beings. On the basis of preliminary test results suggesting that the manufacturer's recommended dosage for dogs of 4.4 mg/kg of body weight caused potentially toxic serum concentrations, a dosage of 3 mg/kg was chosen to conduct a single-dose kinetic study in 6 baboons. Using a single-compartment model, the gentamicin serum half-life for IM administration of 3 mg of gentamicin/kg was 1.58 hours, and serum concentrations remained below the potentially toxic concentrations reported for human beings. We suggest that a dosage of 3 mg/kg is safer than a dosage of 4.4 mg/kg administered IM to baboons. Minimal inhibitory concentrations for 2 Pseudomonas aeruginosa isolates were less than or equal to 1 micrograms/ml. On the basis of our measured elimination half-life of 1.58 hours, it is reasonable to suppose that dosing q24 h will be inadequate to maintain therapeutic serum concentrations. We calculate that serum concentrations will remain at or above our measured minimal inhibitory concentration for P aeruginosa (1 micrograms/ml) for 100% of the treatment time if the animal is dosed q 6h, 78% for dosing q 8h, and 52% for dosing q 12h. Therefore, we suggest 3 mg/kg, q 8h or q 6h as appropriate dosing schedules for the use of gentamicin sulfate administered IM to baboons.  相似文献   

Inapparent rabies virus infection of the central nervous system   总被引：3，自引：0，他引：3  

H R Fischman  J D Strandberg 《Journal of the American Veterinary Medical Association》1973,163(9):1050-1055

  相似文献   

Genetic and Environmental Correlations Among Female Fertility Traits and Milk Production in Different Parities of Swedish Red and White Dairy Cattle     

Anki Roxström  Erling Strandberg  Britt Berglund  Ulf Emanuelson  Jan Philipsson 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):7-14

The main objective of this study was to estimate genetic correlations between fertility and production traits in first, second and third lactations as well as between fertility traits measured in the same way at different ages. The fertility traits studied were: number of inseminations per service period, number of treatments for reproductive disturbances, interval between first and last inseminations, interval between calving and first insemination, and interval between calving and last insemination. Early milk production was measured as the average of the energy-corrected milk yield at the second and third monthly testdays in a lactation. The number of records was approximately 450 000, 350 000, 180 000 and 75 000 in the heifer period, first, second, and third lactations, respectively. A linear, trivariate model that included the effects of herd-year, year, month, age and sire of the cow was applied. To reduce the effect of ongoing selection, 305-days kg protein production in first lactation was included as a variate in all of the analyses. Correlations between the herd-year effects indicated that factors of herd-year level conducive to increased production had a tendency to increase the number of inseminations as well as the number of reproductive treatments, although there was an earlier start and termination of the insemination period. Genetic correlations between fertility traits and production were in the range of 0.2-0.4, all of them unfavourable and higher at later parities. The genetic correlations between fertility traits in the heifer period and the same traits in first lactation were 0.7. Genetic correlations between the first and second lactation varied between 0.7 and 0.9, and between the second and third lactation they were all 0.9 or higher. In conclusion, fertility and production traits need to be selected for simultaneously if fertility is going to be maintained along further genetic improvement on production, and such selection should include fertility results from lactating cows.  相似文献   

The effect of veterinary-treated clinical mastitis and pregnancy status on culling in Swedish dairy cows     

Schneider Mdel P  Strandberg E  Emanuelson U  Grandinson K  Roth A 《Preventive veterinary medicine》2007,80(2-3):179-192

The interaction of the effects of pregnancy status and veterinary-treated clinical mastitis on culling in Swedish dairy cattle was analyzed with survival analysis. The data were from 978,780 cows with first calvings between 1988 and 1996. Four breeds (Swedish Red and White (SRB), Swedish Friesian (SLB), Swedish Polled Breed and Jersey) were included in the analysis, together with the SRB x SLB crossbreds. Length of productive life was defined as the number of days between first calving and culling or censoring (end of data collection). The model (Weibull proportional hazard) included the interaction of parity by pregnancy status by veterinary-treated clinical mastitis, peak test-day milk-yield deviation within herd-year-parity, age at first calving, year by season, region, breed, herd production level, and the random effect of herd. The effects of pregnancy status and veterinary-treated clinical mastitis were modeled as time-dependent covariates. The lactation was divided into five stages during which a veterinary-treated clinical mastitis and culling might occur and in which the pregnancy status was assumed to be known and culling could occur. Open cows had a pronounced effect on culling: they had a very high risk of being culled in all lactations, and it was even higher if they were treated for mastitis in early lactation. For pregnant cows, the later they got pregnant during the lactation, the greater their risk to be culled. The risk associated with cases of veterinary-treated clinical mastitis remained important throughout the lactation.  相似文献   

Genetic analysis of herding behavior in Swedish Border Collie dogs     

Per Arvelius  Sofia Malm  Kenth Svartberg  Erling Strandberg 《Journal of Veterinary Behavior: Clinical Applications and Research》2009,4(6):237-238

  相似文献   

Relationship Between Atmospheric Ammonia Concentration and Nitrogen Content in Terricolous Lichen (Cladonia portentosa)     

Nielsen  Knud Erik  Andersen  H. V.  Strandberg  M.  Løfstrøm  P.  Degn  H. J.  Damgaard  C. 《Water, air, and soil pollution》2014,225(11):1-8

Water, Air, &; Soil Pollution - To biocontrol algal bloom, a novel algicidal bacterium, Enterobacter sp. NP23, was isolated. This strain has an effective algicidal activity against Chlorella...  相似文献