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991.
The results of vaccinating two groups of puppies with commercial vaccines, both of which claimed to provide adequate protection with a final vaccination at 10 weeks of age, were compared. Groups of 19 and 20 puppies with similar titres of maternally derived antibodies against canine parvovirus (cpv), canine distemper virus (cdv) and canine adenovirus type 2 (cav-2) at four weeks of age were vaccinated at six and 10 weeks of age and their responses to each vaccination were measured by comparing the titres against cpv, cdv and cav-2 in the serum samples taken immediately before the vaccination and four weeks later. After the vaccination at six weeks of age, all 19 of the puppies in group 1 had responded to cpv and cdv, and 14 had responded to cav-2; in group 2, 17 of the 20 had responded to cpv, 19 to cdv and 15 to cav-2. In both groups the puppies that did not respond to the first vaccination had responded serologically to cpv, cdv and cav-2 at 10 weeks of age.  相似文献   
992.
Since 1990 the number of glanders outbreaks in race, military and pleasure horses in Asia and South America is steadily increasing. Glanders, which is eradicated in Western Europe, Australia and Northern America, is currently considered a re-emerging disease. Consequently, the disease may be introduced into glanders-free regions by subclinical carriers at any time. The causative agent of glanders, Burkholderia (B.) mallei, is highly contagious and leads to chronic disease in horses whereas in donkeys and mules the disease is acute and often fatal. Occurrence of the disease leads to international trading restrictions and infected animals immediately have to be culled and safely disposed off. In humans B. mallei infection results in a severe clinical course, and is fatal without appropriate therapy. Its pathogenicity makes B. mallei a potential biological agent that may be used in bioterroristic attacks. Due to the eradication of glanders in the second half of the last century, veterinarians in western European countries are no longer familiar with its clinical presentation in solipeds. Having these facts in mind, this review describes the epidemiology, clinical signs, pathology and the current eradication strategy of this interesting zoonosis. Pictures of imported endurance horses infected with glanders taken during an eradication campaign in Dubai, United Arab Emirates, in 2004 illustrate most typical clinical findings.  相似文献   
993.
1. The effects upon bone quality of feeding limestone in flour or particulate form and housing type (cage or aviary) in lines of hens divergently selected for high (H) or low (L) bone strength over 7 generations were investigated. 2. As in previous generations, highly significant phenotypic differences between lines were observed in all measured bone traits at peak egg production (25 weeks) and towards the end of production (56 weeks) in both cage and aviary systems. 3. At 25 weeks there were no significant effects on bone variables of feeding particulate limestone although a significant reduction in osteoclast number was observed at this age. By 56 weeks osteoclast numbers were further reduced in hens fed particulate limestone and beneficial effects on some bone variables were observed in this treatment group. 4. The genotypic and dietary improvements upon bone quality were independent and additive at both ages. There were very few interactive effects. 5. Hens with the freedom to move in an aviary environment during the laying period had improved bone status compared to caged siblings. Environmental and genotypic effects were additive. 6. There were no effects of line on egg production although H line hens had slightly higher egg production by 56 weeks. Egg numbers were unaffected by diet. Eggshell thickness and strength were unaffected by line but hens fed particulate limestone had thicker- and stronger-shelled eggs over the production period as a whole. 7. We conclude that; (a) genetic selection is extremely effective in improving bone strength and resistance to osteoporosis; (b) allowing hens freedom to exercise can also improve bone strength but may increase the risk of keel damage if they do not have genetically-improved bone status; (c) feeding hens a particulate form of limestone from 15 weeks onwards can also increase bone strength and eggshell quality; (d) genetics, environment and nutrition all have independent and additive effects on bone status in laying hens but the relative effectiveness of these factors is genetics > environment > nutrition.  相似文献   
994.
Inhibition of tumour growth and angiogenesis by targeting key growth factor receptors is a promising therapeutic strategy for central nervous system tumours. Characterization of these growth factor receptors in canine primary brain tumours has not been done. Using quantitative real‐time TaqMan polymerase chain reaction (PCR), we evaluated the expression of messenger RNA (mRNA) for five tyrosine kinase growth factor receptors (vascular endothelial growth factor receptor [VEGFR]‐1, VEGFR‐2, endothelial growth factor receptor [EGFR]‐1, platelet‐derived growth factor receptor a [PDGFRa], and c‐Met) relative to normal cerebral cortex in 66 spontaneous canine primary brain tumours. Increased expression of VEGFR‐1 and VEGFR‐2 mRNA was greatest in grade IV astrocytomas (glioblastoma multiforme) and grade III (anaplastic) oligodendrogliomas. EGFR‐1 mRNA expression was more consistently increased than the other receptors in all tumour types, while increased PDGFRa mRNA expression was mostly restricted to oligodendrogliomas. The similarities in increased expression of these tyrosine kinase growth factor receptors in these canine tumours, as compared to data from their human counterparts, suggest that common molecular mechanisms may be present.  相似文献   
995.
  1. The advantage of supplemental sodium bicarbonate (NaHCO3) on eggshell quality in laying hens changes with age. Besides increasing calcium (Ca) secretion in the eggshell gland, it may improve Ca absorption in the intestine or kidney.

  2. Hy-Line Brown layers (n = 384), 25 weeks of age, were allocated to two treatment groups in two experiments, each of which included 4 replicates of 24 hens. Hens were fed a basal diet (control) or the basal diet containing 3 g NaHCO3 g/kg for 50 or 20 weeks in Experiment 1 or 2, respectively. A 24-h continuous lighting regimen was used to allow hens to consume the dietary supplements during the period of active eggshell formation.

  3. In Experiment 1, particularly from 25 to 50 weeks of age, and in Experiment 2, NaHCO3 supplementation favoured hen-d egg production at the expense of lower egg weight. The increased eggshell thickness should have nothing to do with the additional eggshell formation, because of the unchanged egg mass and daily eggshell calcification.

  4. At 35 weeks of age in both experiments, NaHCO3 supplementation increased duodenal expression of calbindin-d28k (CaBP-D28k) protein, contributing to higher Ca retention and balance.

  5. From 50 to 75 weeks of age in Experiment 1, the hens had little response to NaHCO3 supplementation and showed a negative trend on eggshell thickness and strength.

  6. It is concluded that dietary supplementation with 3 g NaHCO3 g/kg improves Ca absorption and eggshell quality of laying hens during the peak but not late production period, with the introduction of continuous lighting.

  相似文献   
996.
997.

Background

The acute phase proteins (APP) serum amyloid A (SAA), haptoglobin, and fibrinogen are valuable blood biomarkers in equine inflammatory diseases, but knowledge of factors influencing their concentrations in blood and peritoneal fluid (PF) of horses with colic is needed.

Objectives

The objective of this study was to investigate the influence of demographics (age, sex, breed), disease process (simple obstruction, strangulating obstruction, inflammatory), disease location, disease duration, hypovolemia, and admission hospital on concentrations of APP, lactate and white blood cell counts (WBC) in horses with colic admitted to 2 referral hospitals.

Animals

The study included 367 horses with colic admitted at 2 referral hospitals.

Methods

Prospective multicenter observational study of clinical data, as well as blood and PF biomarkers. Associations between biomarker concentrations and clinical variables were analyzed using multivariate linear regression analysis.

Results

Increasing pre‐admission duration of colic was associated with increased concentrations of APP in blood and PF. Blood concentrations of SAA and fibrinogen were associated with disease process (inflammatory, strangulations, simple obstructions) in more colic duration groups (5–12 and >24 hours) than any of the other biomarkers. No relevant associations between demographic factors, hospital, or hydration status and the measured biomarkers were found.

Conclusions and Clinical Importance

In horses with colic, concentrations of APP are associated mainly with disease process and duration of colic and may thus be used for assessment of disease independently of demographic or geographic factors. Serum amyloid A may be a diagnostic marker for use in colic differential diagnosis, but further evaluation is needed.  相似文献   
998.

Background

Lagotto Romagnolo (LR) dogs with benign juvenile epilepsy syndrome often experience spontaneous remission of seizures. The long‐term outcome in these dogs currently is unknown. In humans, behavioral and psychiatric comorbidities have been reported in pediatric and adult‐onset epilepsies.

Hypothesis/Objectives

The objectives of this study were to investigate possible neurobehavioral comorbidities in LR with a history of benign familial juvenile epilepsy (BFJE) and to assess the occurrence of seizures after the remission of seizures in puppyhood.

Animals

A total of 25 LR with a history of BFJE and 91 control dogs of the same breed.

Methods

Owners of the LR dogs in the BFJE and control groups completed an online questionnaire about each dog''s activity, impulsivity, and inattention. Principal component analysis (PCA) served to extract behavioral factors from the data. We then compared the scores of these factors between the 2 groups in a retrospective case–control study. We also interviewed all dog owners in the BFJE group by telephone to inquire specifically about possible seizures or other neurological problems after remission of seizures as a puppy.

Results

Lagotto Romagnolo dogs with BFJE showed significantly higher scores on the factors Inattention and Excitability/Impulsivity than did the control group (P = .003; P = .021, respectively). Only 1 of the 25 BFJE LR exhibited seizures after remission of epilepsy in puppyhood.

Conclusions and Clinical Importance

Although the long‐term seizure outcome in BFJE LR seems to be good, the dogs exhibit behavioral abnormalities resembling attention deficit hyperactivity disorder (ADHD) in humans, thus suggesting neurobehavioral comorbidities with epilepsy.  相似文献   
999.
The pharmacokinetic properties of ketoprofen were determined in 4‐week‐old calves after intramuscular (i.m.) injection of a racemic mixture at a dose of 3 mg/kg body weight. Due to possible enantioselective disposition kinetics and chiral inversion, the plasma concentrations of the R(?) and S(+) enantiomer were quantified separately, using a stereospecific HPLC‐UV assay. A distinct predominance of the S(+) enantiomer was observed, as well as significantly different pharmacokinetic parameters between R(?) and S(+) ketoprofen. More in specific, a greater value for the mean area under the plasma concentration–time curve (AUC0→∞) (46.92 ± 7.75 and 11.13 ± 2.18 μg·h/mL for the S(+) and R(?) enantiomer, respectively), a lower apparent clearance (Cl/F) (32.8 ± 5.7 and 139.0 ± 25.1 mL/h·kg for the S(+) and R(?) enantiomer, respectively) and a lower apparent volume of distribution (Vd/F) (139 ± 14.7 and 496 ± 139.4 mL/kg for the S(+) and R(?) enantiomer, respectively) were calculated for the S(+) enantiomer, indicating enantioselective pharmacokinetics for ketoprofen in calves following i.m. administration.  相似文献   
1000.
To estimate the valnemulin pharmacokinetic profile in a swine population and to assess a dosage regimen for increasing the likelihood of optimization. This study was, respectively, performed in 22 sows culled by p.o. administration and in 80 growing‐finishing pigs by i.v. administration at a single dose of 10 mg/kg to develop a population pharmacokinetic model and Monte Carlo simulation. The relationships among the plasma concentration, dose, and time of valnemulin in pigs were illustrated as Ci,v = X0(8.4191 × 10‐4 × e?0.2371t + 1.2788 × 10?5 × e?0.0069t) after i.v. and Cp.o = X0(?8.4964 × 10?4 × e?0.5840t + 8.4195 × e?0.2371t + 7.6869 × 10?6 × e?0.0069t) after p.o. Monte Carlo simulation showed that T>MIC was more than 24 h when a single daily dosage at 13.5 mg/kg BW in pigs was administrated by p.o., and MIC was 0.031 mg/L. It was concluded that the current dosage regimen at 10–12 mg/kg BW led to valnemulin underexposure if the MIC was more than 0.031 mg/L and could increase the risk of treatment failure and/or drug resistance.  相似文献   
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