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111.
Bright A 《British poultry science》2008,49(3):241-249
1. In this study, the calling rates of vocalisations known to indicate distress and aversive events (Alarm calls, Squawks, Total vocalisations) and acoustic parameters of flock noise were quantified from feather and non-feather pecking laying flocks. 2. One hour of flock noise (background machinery and hen vocalisations) was recorded from 21 commercial free-range laying hen flocks aged > or =35 weeks. Ten of the flocks were classified as feather pecking (based on a plumage condition score) and 11 as non-feather pecking. 3. Recordings were made using a Sony DAT recorder and Audio-Technica omni-directional microphone, placed in the centre of the house-1.5 m from the ground. Avisoft-SASlab Pro was used to create and analyse audio spectrograms. 4. There was no effect of flock size or farm on call/s or acoustic parameters of flock noise. However, strain had an effect on the number of Total vocalisation/s; the Hebden Black flock made more calls than Lohmann flocks. Feather pecking flocks gave more Squawk/s and more Total vocalisation/s than non-feather pecking flocks. Feather pecking did not explain variation in alarm call rate or, intensity (dB) and frequency (Hz) measures of flock noise. 5. The differences between Squawk and Total vocalisation call rates of feather and non-feather pecking flocks are a new finding. An increase or change in flock calling rate may be evident before other conventional measures of laying hen welfare such as a drop in egg production or increase in plumage damage, thus enabling farmers to make management or husbandry changes to prevent an outbreak of feather pecking. 相似文献
112.
Jores J Nkando I Sterner-Kock A Haider W Poole J Unger H Muriuki C Wesonga H Taracha EL 《Veterinary immunology and immunopathology》2008,124(1-2):192-197
Contagious bovine pleuropneumonia (CBPP) is a lung disease caused by the bacterial pathogen Mycoplasma mycoides ssp. mycoides small colony type (MmmSC). It has been spreading due to a number of factors including poor vaccine efficacy and poor sensitivity of current diagnostic tests. The purpose of this study was to assess interferon gamma (IFN-gamma) release after stimulation of peripheral blood mononuclear cells (PBMC) from experimentally infected cattle. PBMC collected from 15 artificially infected animals were incubated with different concentrations of total MmmSC antigen. After 72h of incubation the IFN-gamma release was measured and found to be elevated in 11 animals. We did not observe a correlation between IFN-gamma release of animals with and without pathomorphological gross lesions. Therefore, our data do not confirm a role for CD4 T-lymphocytes in protection, since there is no correlation between IFN-g secretion (supposed to be mainly derived from CD4 T-cells) and disease severity. Additionally, we applied immunocytochemistry on affected lung tissue and detected no build up of T-lymphocytes (CD4 T-cells, CD8 T-cells) but a high presence of myeloid cells. 相似文献
113.
Ogunremi O Halbert G Mainar-Jaime R Benjamin J Pfister K Lopez-Rebollar L Georgiadis MP 《Preventive veterinary medicine》2008,83(1):41-51
We evaluated the indirect fluorescent-antibody (IFA) test and complement-fixation (CF) test for diagnosis of equine piroplasmosis in the absence of a gold standard. Using Evan's blue, we estimated the specificity of the IFA test on a parasite-free, field horse population to be 98% (95% confidence interval=97, 99). We observed an excellent test agreement (kappa=0.83) between two collaborating laboratories when the IFA test was performed on identical samples from an endemic area. Using Bayesian analysis with informative prior probability distributions, we estimated the sensitivity of the IFA test to be 92% (95% probability interval, PI=81, 98), and specificity to be 95% (95% PI=88, 99). The CF test sensitivity and specificity estimates were 28% (95% PI=15, 47) and 99% (95% PI=96, 100), respectively. We found the IFA to be superior to the CF test, and the inclusion of Evan's blue in test protocol improved the performance of the IFA test. We conclude that the IFA test for Babesia caballi is a sensitive and specific test for the diagnosis of equine piroplasmosis. 相似文献
114.
Jane E Sykes Sean D Owens Jeralyn C Terry Leann L Lindsay Nicola Pusterla 《Journal of veterinary diagnostic investigation》2008,20(5):616-620
The objective of the current study was to determine the sensitivity and specificity of real-time polymerase chain reaction (real-time PCR) for feline hemoplasmas when applied to DNA extracted from dried whole-blood smears in comparison to that for DNA extracted from liquid whole blood. Blood samples were collected into ethylenediamine tetra-acetic acid tubes from 305 cats with possible or suspected hemoplasmosis, and dried blood smears from each sample were prepared. DNA was extracted from blood smears and a 160-microl aliquot of each liquid blood sample by using a robotic extractor and was subjected to real-time PCR for feline glyceraldehyde-3-phosphate dehydrogenase (liquid blood), 18S ribosomal RNA (dried blood), and "Candidatus Mycoplasma haemominutum", Mycoplasma haemofelis, and "Candidatus Mycoplasma turicensis" DNA. When using the results for liquid whole blood as the gold standard, the sensitivity of each assay for "Ca. M. haemominutum", M. haemofelis, and "Ca. M. turicensis" was 49 of 66 (74%), 11 of 13 (85%), and 11 of 20 (55%), respectively. The specificity of each assay was 224 of 234 (96%), 287 of 287 (100%), and 280 of 280 (100%), respectively. When possible, liquid blood samples should be submitted for detection of feline hemoplasmas by using real-time PCR. The improved sensitivity of real-time PCR on blood smears for M. haemofelis compared with that of the other hemoplasma species may reflect the higher organism burdens associated with infection with this species. 相似文献
115.
116.
Validation of the indirect fluorescent antibody and the complement fixation tests for the diagnosis of Theileria equi 总被引:1,自引:0,他引:1
Ogunremi O Georgiadis MP Halbert G Benjamin J Pfister K Lopez-Rebollar L 《Veterinary parasitology》2007,148(2):102-108
The indirect fluorescent antibody (IFA) test for Theileria equi was evaluated to assess test's suitability for the serological diagnosis of equine piroplasmosis, to provide performance parameters for the purpose of test validation, and to compare it with the complement fixation (CF) test. Using a protocol that included Evan's blue, the specificity of the IFA test was estimated at 99.0% for T. equi by the classical method of analysis, and 96.6% by the Bayesian method. The use of Evan's blue in the test protocol increased test specificity and contributed to an excellent test agreement between two collaborating laboratories (kappa = 0.96). Using Bayesian analysis, the sensitivity estimate for the IFA test was 89.2%. The CF test sensitivity and specificity estimates for T. equi were 63.1 and 96.4%, respectively, as determined by Bayesian analysis. The IFA test was more sensitive than the CF test but the specificity estimates were similar. 相似文献
117.
Fred A. Williams JR DVM Ronald M. Bright DVM MS Diplomate ACVS Gregory B. Daniel DVM MS Diplomate ACVR Kevin A. Hahn DVM PhD Steve A. Patton DVM MS Diplomate ACVP 《Veterinary surgery : VS》1999,28(5):348-354
OBJECTIVE: To determine if once-daily colonic irrigation results in fecal continence for a 24-hour period in dogs with colostomies and if colonic volume increased in response to the irrigation. STUDY DESIGN: A prospective controlled experimental study. ANIMALS: Four intact male and one intact female mixed breed dogs. MATERIALS: All dogs received left end-on paralumbar colostomies. Four dogs received once-daily colonic irrigation for 8 weeks, whereas the control dog did not. Daily fecal weights were recorded for the length of the study in all dogs. Barium enema studies and volumetric studies were used to determine colonic volumes. RESULTS: Daily fecal weights were significantly decreased in treatment dogs compared with the control dog. Colonic volume increased in irrigated dogs in response to daily irrigation over the 8 week period of the study. CONCLUSIONS: Colonic irrigation resulted in significantly decreased fecal production over a 24-hour period. Therefore management of dogs with colostomies would be more practical and cost effective. It did not result in complete fecal continence in this study. Further clinical studies are indicated to determine if longer periods of irrigation would result in complete continence. 相似文献
118.
Pulsed Doppler assessment of left ventricular diastolic function in normal and cardiomyopathic cats.
J M Bright M E Herrtage J F Schneider 《Journal of the American Animal Hospital Association》1999,35(4):285-291
Left ventricular (LV) diastolic function was evaluated in 16 cats with primary hypertrophic cardiomyopathy (HCM) using pulsed Doppler (PD) assessment of transmitral flow and isovolumic relaxation time. Data obtained was compared to data from 12 healthy, adult, research cats. Compared to normal cats, the HCM group showed significantly (p value less than 0.05) reduced early LV inflow velocities (mean +/- standard error [SE], peak velocity of 0.70+/-0.04 m/s versus 0.54+/-0.04 m/s and integrated velocity of 0.48+/-0.08 m/s versus 0.37+/-0.03 m/s); a reduced rate of deceleration of early inflow (mean+/-SE, -12.0+/-1.0 m/s2 versus -5.1+/-1.1 m/s2); prolonged isovolumic relaxation time (mean +/- SE, 45.7+/-3.3 ms versus 76.0+/-3.1 ms); and increased atrial systolic flow velocities (mean +/- SE, peak velocity of 0.29+/-0.04 m/s versus 0.48+/-0.04 m/s and integrated velocity of 0.21+/-0.03 m/s versus 0.34+/-0.03 m/s). The results suggest that PD provides a noninvasive method of identifying and quantifying functional diastolic impairment in cats with HCM. 相似文献
119.
Alex P. Justen Antonio R. G. Monteiro Jane M. G. Mikcha Eliane Gasparino Ádina B. Delbem 《Journal Of Aquatic Food Product Technology》2017,26(3):258-266
This study aimed to develop extruded snacks including flour obtained from Nile tilápia carcasses, and then evaluate the chemical composition, colorimetry, thiobarbituric acid reactive substances, and microbiology. There was a significant increase in the levels of crude protein, ether extract, ash, and minerals, as well as a reduction in carbohydrates as more flour was included in the snacks. Increased levels of flavored flour caused reduction in the brightness of snacks. Oxidative rancidity was not detected in snacks. The inclusion of flour improved the nutritional value of extruded snacks without changing sensory characteristics. Microbiologically, the snacks are suitable for human consumption. 相似文献
120.
Hawkins SS Griffiths LJ Dezateux C Law C;Millennium Cohort Study Child Health Group 《Public health nutrition》2007,10(9):891-896
OBJECTIVE: To examine the relationship of maternal employment characteristics, day care arrangements and the type of maternity leave pay to breast-feeding for at least 4 months. DESIGN: Cohort study. SETTING: Babies aged 9 months in the Millennium Cohort Study, born between September 2000 and January 2002. SUBJECTS: A total of 6917 British/Irish white employed mothers with singleton babies. RESULTS: Mothers employed part-time or self-employed were more likely to breast-feed for at least 4 months than those employed full-time (adjusted rate ratio (aRR) and 95% confidence interval (CI) 1.30 (1.17-1.44) and 1.74 (1.46-2.07), respectively). The longer a mother delayed her return to work postpartum, the more likely she was to breast-feed for at least 4 months (P for trend < 0.001). Mothers were less likely to breast-feed for at least 4 months if they returned to work for financial reasons (aRR 0.86, 95% CI 0.80-0.93) or used informal day care arrangements rather than care by themselves or their partner (aRR 0.81, 95% CI 0.71-0.91). Mothers were more likely to breastfeed for at least 4 months if their employer offered family-friendly (aRR 1.14, 95% CI 1.02-1.27) or flexible work arrangements (aRR 1.24, 95% CI 1.00-1.55), or they received Statutory Maternity Pay (SMP) plus additional pay during their maternity leave rather than SMP alone (aRR 1.13, 95% CI 1.02-1.26). These findings were independent of confounding factors, such as socio-economic status and maternal education. CONCLUSIONS: Current policies may encourage mothers to enter or return to employment postpartum, but this may result in widening inequalities in breast-feeding and persistence of low rates. Policies should aim to increase financial support and incentives for employers to offer supportive work arrangements. 相似文献