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171.
Feasibility and inter-session repeatability of cold and mechanical quantitative sensory testing (QST) were assessed in 24 normal dogs. Cold thermal latencies were evaluated using a thermal probe (0 °C) applied to three pelvic limb sites. Mechanical thresholds were measured using an electronic von Frey anesthesiometer (EVF) and a blunt-probed pressure algometer (PA) applied to the dorsal aspect of the metatarsus. All QST trials were performed with dogs in lateral recumbency. Collection of cold QST data was easy (feasible) in 19/24 (79%) dogs. However, only 18.4%, 18.9% and 13.2% of cold QST trials elicited a response at the medial tibia, third digital pad and plantar metatarsal regions, respectively. Collection of mechanical QST data was easy (feasible) in 20/24 (83%) dogs for both EVF and PA.At consecutive sampling times, approximately 2 weeks apart, the average EVF sensory thresholds were 414 ± 186 g and 379 ± 166 g, respectively, and the average PA sensory thresholds were 1089 ± 414 g and 1028 ± 331 g, respectively. There was no significant difference in inter-session or inter-limb threshold values for either mechanical QST device. The cold QST protocol in this study was achievable, but did not provide consistently quantifiable results. Both mechanical QST devices tested provided repeatable, reliable sensory threshold measurements in normal, client-owned dogs. These findings contribute to the validation of the EVF and PA as tools to obtain repeated QST data over time in dogs to assess somatosensory processing changes.  相似文献   
172.
Models in QTL mapping can be improved by considering all potential variables, i.e. we can use remaining traits other than the trait under study as potential predictors. QTL mapping is often conducted by correcting for a few fixed effects or covariates (e.g. sex, age), although many traits with potential causal relationships between them are recorded. In this work, we evaluate by simulation several procedures to identify optimum models in QTL scans: forward selection, undirected dependency graph and QTL-directed dependency graph (QDG). The latter, QDG, performed better in terms of power and false discovery rate and was applied to fatty acid (FA) composition and fat deposition traits in two pig F2 crosses from China and Spain. Compared with the typical QTL mapping, QDG approach revealed several new QTL. To the contrary, several FA QTL on chromosome 4 (e.g. Palmitic, C16:0; Stearic, C18:0) detected by typical mapping vanished after adjusting for phenotypic covariates in QDG mapping. This suggests that the QTL detected in typical mapping could be indirect. When a QTL is supported by both approaches, there is an increased confidence that the QTL have a primary effect on the corresponding trait. An example is a QTL for C16:1 on chromosome 8. In conclusion, mapping QTL based on causal phenotypic networks can increase power and help to make more biologically sound hypothesis on the genetic architecture of complex traits.  相似文献   
173.
174.

Background

Detection of clinically relevant pain relief in cats with degenerative joint disease (DJD) is complicated by a lack of validated outcome measures and a placebo effect.

Hypothesis/Objectives

To evaluate a novel approach for detection of pain relief in cats with DJD.

Animals

Fifty‐eight client‐owned cats.

Methods

Prospective, double‐masked, placebo‐controlled, stratified, randomized, clinical study. Enrolled cats were 6–21 years of age, with owner‐observed mobility impairment, evidence of pain in at least 2 joints during orthopedic examination, and overlapping radiographic evidence of DJD, and underwent a 2‐week baseline period, 3‐week treatment period with placebo or meloxicam, and 3‐week masked washout period. Outcome measures were evaluated at days 0, 15, 36, and 57.

Results

Both groups significantly improved after the treatment period (day 36) on client‐specific outcome measures (CSOM) and feline musculoskeletal pain index (FMPI) (P < .0001 for both); there was no difference between the groups on CSOM or FMPI score improvement. After the masked washout period, more cats that received meloxicam during the treatment period had a clinically relevant decrease in CSOM score (P = .048) and FMPI score (P = .021) than cats that received placebo.

Conclusions and Clinical Importance

Using both a client‐specific and a general clinical metrology instrument, owners of cats with DJD were able to detect evident recurrence of clinical signs after withdrawal of active medication than after withdrawal of placebo, and that this study design might be a novel and useful way to circumvent the placebo effect and detect the efficacy of pain‐relieving medications.  相似文献   
175.
Diagnosis of feline immunodeficiency virus (FIV) infection by polymerase chain reaction (PCR) has recently become available, but little is known about the performance of this assay. The purpose of this study was to determine the sensitivity and specificity of PCR diagnosis of FIV infection. Replicate aliquots of blood samples from cats identified as FIV positive or negative by 2 previous enzyme-linked immunosorbent assay (ELISA) results, and from clinically healthy dogs, were submitted to different laboratories for FIV serologic diagnosis and PCR. The PCR products obtained in 1 laboratory were sequenced to determine the FIV subtype. The PCR assays correctly identified 100%, 80%, and 50% of the FIV-positive samples, and 100%, 90%, and 70% of FIV-negative samples. Each dog sample was reported as FIV PCR positive at least once, and FIV subtypes A, B, and C were identified. It was concluded that PCR tests currently available for FIV infection are unreliable, with highly variable sensitivity and specificity.  相似文献   
176.
Nine strains of fungi that isolated from alpine meadow were used as research objects. The laccase-producing strains were identified by rDNA-ITS method. According to the strains, guaiacol, anthrone, catechol and neighbors were identified. Growth on selective medium of toluidine, o-toluidine, crnaphthol, benzidine, gallic acid as substrate, colony size, size of the color circle produced by laccase-catalyzed redox reaction, and the degree of color depth, the laccase-producing fungus is firstly screened, and the laccase activity is determined by the liquid-producing enzyme fermentation method using ABTS as a substrate for re-screening. The results showed that strain 1. 9 was Uncultured fungus clone. 2. la was Scytalidium, 310b was Marasmius tricolor, 2.1c was Saccharicola, 2. 3a was fungal sp, 2. 4d was Saccharicola. 10a was Marasmiusrotalis, 3. 7c was Alternaria. WB was Verticilliumlongisporum. The screening results showed that except for strain 3. 7c, the other 8 strains basically produced oxidative bands on the culture medium with guaiacol, anthrone, ortho-toluidine and benzidine as substrates, and cultured in gallic acid substrate. No oxidative bands were produced on the culture medium; strains 1. 9, 2. la, 310b, 2. 4d, 10a, 2. lc, and 2. 3a all had laccase activity, and strain 310b had stronger laccase activity than the other strains. © 2019 China Agricultural University. All rights reserved.  相似文献   
177.
Influenza‐like illness was noted in people and pigs in attendance at an Ohio county fair in August 2007. The morbidity rate in swine approached 100% within 1–2 days of initial clinical signs being recognized, and approximately two dozen people developed influenza‐like illness. Triple‐reassortant swine H1N1 influenza viruses were identified in both pigs and people at the fair. The identified viruses (A/Sw/OH/511445/2007, A/Ohio/01/2007, and A/Ohio/02/2007) were similar to H1N1 swine influenza viruses currently found in the U.S. swine population. This case illustrates the possibility of transmission of swine influenza in settings where there is close human/swine interaction.  相似文献   
178.
During the onset of lactation, there is a dramatic increase in the expression of glucose transporters (GLUT) and a group of enzymes involved in milk fat synthesis in the bovine mammary gland. The objective of this study was to investigate whether the lactogenic hormones mediate both of these increases. Bovine mammary explants were cultured for 48, 72, or 96 h with the following hormone treatments: no hormone (control), IGF-I, insulin (Ins), Ins + hydrocortisone + ovine prolactin (InsHPrl), or Ins + hydrocortisone + prolactin + 17β-estradiol (InsHPrlE). The relative expression of β-casein, α-lactalbumin, sterol regulatory element binding factor 1 (SREBF1), fatty acid synthase (FASN), acetyl-CoA carboxylase α (ACACA), stearyol-CoA desaturase (SCD), GLUT1, GLUT8, and GLUT12 were measured by real-time PCR. Exposure to the lactogenic hormone combinations InsHPrl and InsHPrlE for 96 h stimulated expression of β-casein and α-lactalbumin mRNA by several hundred-fold and also increased the expression of SREBF1, FASN, ACACA, and SCD genes in mammary explants (P < 0.01). However, those hormone combinations had no effect on GLUT1 or GLUT8 expression and inhibited GLUT12 expression by 50% after 72 h of treatment (P < 0.05). In separate experiments, the expression of GLUTs in the mouse mammary epithelial cell line HC11 or in bovine primary mammary epithelial cells was not increased by lactogenic hormone treatments. Moreover, treatment of dairy cows with bovine prolactin had no effect on GLUT expression in the mammary gland. In conclusion, lactogenic hormones clearly stimulate expression of milk protein and lipogenic genes, but they do not appear to mediate the marked up-regulation of GLUT expression in the mammary gland during the onset of lactation.  相似文献   
179.
To evaluate the residual target tissues for better monitoring of amantadine abuse in broiler chickens, 22‐day‐old commercial Arbor Acres broiler chickens were, respectively, fed with 10, 20, and 40 mg/kg of amantadine for five consecutive days. Plasma, breast, and liver tissue samples from the chickens were collected 0, 4, 16, 24, 48, 96, 144, and 312 h after amantadine withdrawal. The high‐performance liquid chromatography–tandem mass spectrometry method was used to detect the concentrations of amantadine. The highest concentration was found in the chicken liver and it took the longest time for amantadine to vanish by metabolism. In the high‐dose group, amantadine residues were still detected 312 h after amantadine withdrawal. As the amantadine dose increased, amantadine residues in the chicken liver were more slowly to disappear than in other tissues. Even if approximately the same concentration of amantadine residues was found in chicken breast and plasma samples, it took a shorter time before the residues were eliminated. In the medium‐ and high‐dose groups, the concentrations of amantadine residues in chicken liver samples were substantially higher than those in chicken breast and plasma samples, and it took more time to eliminate them. Therefore, the chicken liver can be used as a target tissue to detect illegal use of amantadine.  相似文献   
180.
1. An experiment was conducted to test the independent and combined effects of high dietary calcium and protein concentrations on the induction of visceral gout in growing birds of a layer strain. 2. One hundred and sixty healthy birds were randomly divided into 4 groups at 35 d of age. The different groups were given 4 diets containing normal or high concentrations of dietary calcium or crude protein in a 2 x 2 factorial experiment for 30 d. The diets contained normal calcium (Ca) and crude protein (CP) (NCNP, 8.5 g Ca/kg and 175g CP/kg), high calcium and normal protein (HC, 36.3 g Ca/kg and 175 g CP/kg), normal calcium and high protein (HP, 8.8 g Ca/kg and 245 g CP/kg) or high calcium and high protein (HCHP, 36.8 g Ca/kg and 242 g CP/kg), respectively. 3. Typical visceral gout was induced by the HCHP diet. The HCHP and HC diet caused severe kidney damage. The HP diet did not cause kidney damage, but significantly increased plasma uric acid and inorganic phosphorus concentrations. 4. The HC diet significantly increased plasma uric acid, calcium and sodium, but significantly decreased plasma inorganic phosphorus, potassium and magnesium concentrations. The HCHP diet significantly increased plasma uric acid, calcium and sodium. 5. Urine volumes were significantly higher on the HCHP and HC diets than on the control. The growers raised on HC and HCHP diets had significantly higher total quantity of 24 h urinary excretion of uric acid, calcium, magnesium, inorganic phosphorus and potassium and a significantly lower 24 h urinary excretion of sodium. The growers fed on the HP diet had a higher 24 h urinary excretion of uric acid and inorganic phosphorus than the control. 6. It is concluded that growing layer birds should not be fed on layer rations.  相似文献   
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