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Biomolecular relationship of whole protein of Mannheimia haemolytica, Pasteurella trehalosi and Pasteurella multocida of sheep Texto completo
2010
Amal M. El-Sawah | Eman M. El-Rawy
P. multocida contains one or more antigenic determinant of different proportions responsible for partial protection offered by the heterologous serovars. SDS-PAGE analysis of the whole protein profile prepared from sheep local isolates of P. multocida types (A, D), Mannheimia haemolytica type (A), P. trehalosi type (T) as well as standard strain of P. multocida (B6) revealed that the protein profile exhibited some differences with variable molecular masses ranged between 14 to 116 kDa. There are sharing protein subunits of molecular masses of 66, 37 and 28 kDa as the unique cross-reactive antigens in all isolates. The protection percentage for the vaccinated mice with inactivated M. haemolytica against the challenge with virulent strain of P. multocida type A, D and B6 are 30%, 30% and 20% respectively and 25%, 25% and 20% respectively in the groups of mice vaccinated with inactivated P. trehalosi so, there is cross reaction but limited cross protection between pasteurella isolates. The suggested vaccine must contain local isolates of P. multocida serotypes A, D and B6 as well as M. haemolytica and P. trehalosi.
Mostrar más [+] Menos [-]Effect of seasonal variations on performance and parasitic infestation of cultured fish in Fayoum governorate Texto completo
2010
H. H. Emeash | M. A. El-Bably | Asmaa N. Mohamed
A field study was carried out in a fish farm to study the effect of seasonal variations during the production period on performance and parasitic infestation of cultured fish. Water samples were obtained to determine the Physio-chemical investigation of water in the examined farm to estimate temperature, dissolved oxygen, PH, ammonia, nitrite, nitrate, salinity, total alkalinity and total hardness. Fish samples were obtained for parasitological examination to detect external parasitic infestation.The results referred that an elevation of water temperature during summer months leading to slight increase of PH of water, while dissolved oxygen values decreased from 6.8±0.15 to 6.0±1.5 throughout the study period. The mean values of ammonia, nitrite and nitrate reach the maximum in July and August months (0.71±0.18, 0.20±0.07 and 3.1±0.07 mg/l respectively). In addition there was a slightly increase of the total alkalinity and total hardness at beginning of the study (37.8±3.0 and 147.0±5.0mg/l respectively) reached the maximum levels in the summer months (44.4±2.8 and 182.8±6.0 mg/l respectively). It can be noticed that the most prevalent ectoparasitic affecting cultured Tilapia are Trichodina,Monogenia and Epistylis. It can be noticed that, the average initial body weight of examined fish was 6.8±2.3 gm and reached 218.0±3.8 gm. at the end of experiment (210 days) with an average of daily weight gain 1.01 ±0.07 gm. From the aforementioned results, it can be concluded that special attention to Physio-chemical parameters of water fish ponds and regular inspection of fish parasitic infestation particularly during summer months obtained a good fish performance as well as high body weight gain and high survival percentage.
Mostrar más [+] Menos [-]Incidence of hoof affections in equine Texto completo
2010
M. M. Seif | A. M. Sedeek | M. Z. Fathy | G. A. Ragab
This study was conducted on 1178 lamed animals of equine species. Cases were classified according to the species, affected part of the foot, and nature of the affection. Hoof affections represented in about 722 animals with 61.3 % of total lame animals. The percentages of hoof affections were higher in forefeet than hind feet. The present study revealed that sandy cracks, toe- in and long toe were the predominant hoof wall affections. The corn was the highest sole affections followed by white line disease and the lowest percentages were flat foot and bruised sole. The highest affection percentage in frog was thrush followed by picked up nail and the lowest was in under run heel.
Mostrar más [+] Menos [-]Increased risk of chronic wasting disease in Rocky Mountain elk associated with decreased magnesium and increased manganese in brain tissue Texto completo
2010
White, Stephen N. | O’Rourke, Katherine I. | Gidlewski, Thomas | VerCauteren, Kurt C. | Mousel, Michelle R. | Phillips, Gregory E. | Spraker, Terry R.
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) of Rocky Mountain elk in North America. Recent studies suggest that tissue and blood mineral levels may be valuable in assessing TSE infection in sheep and cattle. The objectives of this study were to examine baseline levels of copper, manganese, magnesium, zinc, selenium, and molybdenum in the brains of Rocky Mountain elk with differing prion genotypes and to assess the association of mineral levels with CWD infection. Elk with leucine at prion position 132 had significantly lower magnesium levels than elk with 2 copies of methionine. Chronic wasting disease-positive elk had significantly lower magnesium than control elk. The incorporation of manganese levels in addition to magnesium significantly refined explanatory ability, even though manganese alone was not significantly associated with CWD. This study demonstrated that mineral analysis may provide an additional disease correlate for assessing CWD risk, particularly in conjunction with genotype.
Mostrar más [+] Menos [-]Changes of very low-density lipoprotein concentration in hepatic blood from cows with fasting-induced hepatic lipidosis Texto completo
2010
The purpose of this study was to evaluate changes of very low-density lipoprotein (VLDL) components in hepatic blood (HB) from 5 nonlactating nonpregnant cows fasted from days 0 to 3 and subsequently refed to day 10 and, in addition, to assess those of other lipoproteins. Increased phospholipid concentrations in each lipoprotein after the start of fasting suggested their availability for the surface lipids of lipoproteins. Although the VLDL-triglyceride (TG) concentration in HB from all cows increased on day 1, the value on day 4 became similar to that on day 0. However, the concentration on day 10 was significantly increased. In all cows, the decreased ratio of the VLDL-TG concentration in HB to the non-esterified fatty acids (NEFA) concentration in portal blood (PB) on day 4 appeared to reflect relatively decreased secretion of TG as VLDL by NEFA excessively mobilized to the liver via PB. The markedly increased ratio on day 10 was considered to contribute to the improvement of hepatic lipidosis.
Mostrar más [+] Menos [-]A transducer for measuring force on surgical sutures Texto completo
2010
The objective of this study was to validate, both in vitro and in an ex vivo model, a technique for the measurement of forces exerted on surgical sutures. For this purpose, a stainless steel E-type buckle force transducer was designed and constructed. A strain gauge was mounted on the central beam of the transducer to measure transducer deformation. The transducer was tested and calibrated on a single strand of surgical suture during cyclic loading. Further validation was performed using a previously published cadaveric model of laryngoplasty in the horse. Linear regression of transducer output with actual force during calibration tests resulted in mean R2 values of 1.00, 0.99, and 0.99 for rising slope, falling slope, and overall slope, respectively. The R2 was not less than 0.96 across an average of 75 cycles per test. The difference between rising slope and falling slope was 4%. Over 45 846 samples, the predicted force from transducer output showed a mean error of 4%. In vitro validation produced an adjusted R2 of 0.99 when the force on the suture was regressed against translaryngeal pressure in a mixed-effects model. E-type buckle force transducers showed a highly linear output over a physiological force range when applied to surgical suture in vitro and in an ex vivo model of laryngoplasty. With appropriate calibration and short-term in vivo implantation, these transducers may advance our knowledge of the mechanisms of success and failure of techniques, such as laryngoplasty, that use structural suture implants.
Mostrar más [+] Menos [-]Evaluation of a veterinary-based syndromic surveillance system implemented for swine Texto completo
2010
Practicing veterinarians play an important role in detecting the initial outbreak of disease in animal populations. A pilot study was conducted to determine the feasibility of a veterinary-based surveillance system for the Ontario swine industry. A total of 7 practitioners from 5 clinics agreed to submit information from July 1, 2007 to June 30, 2008. The surveillance program was evaluated in terms of timeliness, compliance, geographic coverage, and data quality. Our study showed that the veterinary-based surveillance system was acceptable to practitioners and produced useful data. The program obtained information from 25% of pig farms in Ontario during this time period. However, better communication with practitioners, more user-friendly recording systems that can be adapted to each clinic’s management system, active involvement of the clinics’ technical personnel, and the use of financial incentives may help to improve compliance and timeliness.
Mostrar más [+] Menos [-]A clinical field trial to evaluate the efficacy of vaccination in controlling Salmonella infection and the association of Salmonella-shedding and weight gain in pigs Texto completo
2010
A clinical field trial was performed to determine the effectiveness of an autogenous Salmonella Typhimurium bacterin compared with a commercial live S. Choleraesuis vaccine in pigs. The association between Salmonella shedding and weight gain was also investigated. Nine cohorts of weaned pigs, (330 to 350 pigs per cohort), were randomly assigned to 1 of 3 treatment groups (injection with S. Typhimurium bacterin, vaccination via water with S. Choleraesuis vaccine, or a control group receiving no vaccine). In each cohort, the average daily gain was calculated for a selected pen throughout the production stage. Pen (pooled) fecal samples were collected bi-weekly and cultured. The odds of Salmonella shedding in both vaccinated groups was higher than in the control group (P < 0.05). The prevalence of Salmonella shedding declined overall as pigs aged (P = 0.04). However, the control pigs showed the smallest decrease in Salmonella shedding over the entire production stage, while prevalence of Salmonella shedding in the vaccinated groups decreased twice as much as the control group over the entire production stage. Salmonella Typhimurium var. Copenhagen DT104, S. Cerro, and S. Agona, which had been isolated on the study farm previously, were recovered from pigs in this study. Shedding of S. Typhimurium var. Copenhagen decreased over time in both vaccine treatment groups. On the other hand, S. Cerro shedding rate was lower in the control pigs compared with vaccinated pigs and S. Agona could be recovered only from the samples collected from S. Choleraesuis vaccinated pigs. The pigs from pens with a higher Salmonella recovery rate experienced slower growth compared with pigs from pens where Salmonella was not isolated. This latter finding indicates that there might be an economic incentive for producers to try to control endemic salmonellosis if effective programs could be developed.
Mostrar más [+] Menos [-]Characteristics of the molecular diversity of the outer membrane protein A gene of Haemophilus parasuis Texto completo
2010
The molecular diversity of the gene encoding the outer membrane protein A (OmpA) of Haemophilus parasuis has been unclear. In this study, the structural characteristics, sequence types, and genetic diversity of ompA were investigated in 15 H. parasuis reference strains of different serovars and 20 field isolates. Three nucleotide lengths of the complete open reading frame (ORF) of ompA were found: 1098 base pairs (bp), 1104 bp, and 1110 bp. The OmpA contained 4 hypervariable domains, mainly encoding the 4 putative surface-exposed loops, which makes it a potential molecular marker for genotyping. Western blot analysis showed that the recombinant OmpAs of serovars 4 and 5 could cross-react with antiserum to all 15 serovars. Hence, although ompA of H. parasuis exhibited high variation among serovars, this variation did not seem to affect the strong antigenic characteristics of OmpA.
Mostrar más [+] Menos [-]Distribution of capsular serotypes and virulence markers of Streptococcus suis isolated from pigs with polyserositis in Korea Texto completo
2010
Kim, Duyeol | Han, Kiwon | Oh, Yeonsu | Kim, Chung Hyun | Kang, Ikjae | Lee, Jeehoon | Gottschalk, Marcelo | Chae, Chanhee
The objective of this study was to determine the capsular serotypes and potential virulence factors of Streptococcus suis isolated from pigs with polyserositis. Among the 24 isolates evaluated, serotype 3 [7 (29%) of the isolates] and serotype 4 [5 (21%)] were the most common. The isolates were also studied for the presence of the genes mrp, epf, and sly, which encode muramidase-released protein (MRP), extracellular factor (EF), and suilysin (SLY), respectively. Of the 24 isolates, 8 carried mrp: 4 of serotype 3, 2 of serotype 2, and 2 of serotype 4. One mrp+ isolate (serotype 2) also carried the epf gene. All 24 isolates carried the sly gene. The serotype and genotype distribution greatly differed from that reported for isolates from pigs with other clinical manifestations of S. suis infection in other countries.
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