1. Broiler chickens were killed using either an electrical waterbath (WB system) delivering 120 mA per bird (50 Hz, alternating current, AC) for 4 s or an alternative stun/kill method (ASK system); where head-only stunning for 1 s was immediately followed by head-to-body (vent) application for 1 s (150 mA, 50 Hz sine wave AC). Within each stun/kill system, the neck was cut ventrally or unilaterally 20, 60, or 180 s after killing. In addition, a control group of broilers was stunned with 100 mA per bird in a waterbath using 1500 Hz AC for 4 s and were bled by a ventral neck cut within 20 s. 2. Blood leaving the neck cut was collected for 90 s in a bin placed on an electronic balance and blood loss (g/kg body weight) calculated. 3. Individually identified, unplucked and uneviscerated carcases were held at ambient temperature until the end of the experimental day and then stored overnight in an air chiller (5 degrees C). The carcases were dissected and the incidence of broken furculum and coracoid bones, haemorrhaging in P. minor and P. major muscles, and discolouration of P. major muscles were determined. 4. When neck cutting was performed in broilers 20 s after the stun or kill, the ASK and WB systems, in comparison with high frequency stunning, produced on average about 10 g per kg less bleed out. Within the stun/kill systems, broilers killed by ASK had a greater bleed out than in the WB system. Neck cutting at 20 s or 60 s post-kill resulted in a greater bleed out than when performed after a delay of 180 s. Ventral or unilateral neck cutting resulted in a similar bleed out. 5. Stunning broilers with 1500 Hz AC resulted in lower incidences of broken bones, haemorrhaging in breast muscles and muscle discolouration post mortem than the stun/kill systems. These defects were significantly lower in the ASK than in the WB system. Delayed neck cutting increased the severity of discolouration occurring Post mortem in the breast muscles. 6. It is suggested that broilers killed by ASK can be neck cut with a delay of up to 180 s without compromising bleed out. The incidence of broken bones and haemorrhaging in breast muscles are significantly less with ASK than WB. 7. Owing to the commercial benefits and potential for improved welfare at slaughter, ASK would appear to be a better method than WB. 相似文献
The rocket immunoelectrophoresis (RIE) test was used for the qualitative detection and quantitative estimation of infectious bursal disease virus (IBDV) specific antigen in experimentally infected chickens and samples collected from suspected outbreaks. The IBDV specific antigen was detected in the bursae of experimentally inoculated chickens up to 5 days post infection (PI) by the agar gel precipitation (AGP) test and 7 days PI by the RIE test. The RIE detected IBDV specific antigen in a significantly greater number of samples collected from the field outbreaks than the conventional AGP test. Exudative bursae were found to have a higher antigen content than haemorrhagic bursae and are recommended as the material of choice for diagnosis of IBD. This test could also be used to quantify IBDV specific antigen in commercial killed vaccines. 相似文献
White tail disease (WTD) caused by Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) is a serious problem in prawn hatcheries. The gene for capsid protein of MrNV (MCP43) was cloned into pRSET B expression vector. The MCP43 protein was expressed as a protein with a 6‐histidine tag in Escherichia coli GJ1158 with NaCl induction. This recombinant protein, which was used to raise the antiserum in rabbits, recognized capsid protein in different WTD‐infected post‐larvae and adult prawn. Various immunological methods such as Western blot, dot blot and ELISA techniques were employed to detect MrNV in infected samples using the antiserum raised against recombinant MCP43 of MrNV. The dot blot assay using anti‐rMCP43 was found to be capable of detecting MrNV in WTD‐infected post‐larvae as early as at 24 h post‐infection. The antiserum raised against r‐MCP43 could detect the MrNV in the infected samples at the level of 100 pg of total protein. The capsid protein of MrNV estimated by ELISA using anti‐rMCP43 and pure r‐MCP43 as a standard was found to increase gradually during the course of infection from 24 h p.i. to moribund stage. The results of immunological diagnostic methods employed in this study were compared with that of RT‐PCR to test the efficiency of antiserum raised against r‐MCP43 for the detection of MrNV. The Western blot, dot blot and ELISA detected all MrNV‐positive coded samples as detected by RT‐PCR. 相似文献
Small-scale Forestry - Although protected areas are central to global biodiversity conservation, most land lies within unprotected areas. In the developing world forest habitats have received... 相似文献
1. The objective of the experiment was to determine the influence of age, sex and rearing system on Toll-like receptor 7 (TLR7) gene expression in gut, lung and lymphoid tissues and physiological responses to stress in male and female indigenous ducks of Tamil Nadu, India.
2. A total of 36 ducks (12 males and 24 females) were obtained from local farmers and tissue samples of gut tissues (duodenum, jejunum, ileum and caecum), lymphoid organs (spleen and bursa) and lungs were collected in RNAlater solution followed by RNA extraction.
3. After normalisation to β-actin (endogenous control) qPCR analysis identified a significant effect of age, sex and rearing system on TLR7 expression in the ducks.
4. A significant up-regulation of TLR7 expression was observed in lungs, duodenum, jejunum, ileum and caecum of sexually mature (45 wk) compared with that of immature ducks (16 wk). Among sexes, male ducks had significantly higher TLR7 expression than female ducks.
5. Age and sex interactions were significant in lungs, duodenum, jejunum and caecum. Ducks reared in an extensive housing system showed significantly higher TLR7 expression in bursa, lungs, duodenum, ileum and caecum compared to intensively reared ducks. There were no effects of age, sex and rearing systems on TLR7 expression in the spleen.
6. The heterophil-to-lymphocyte ratio and serum corticosterone were higher in ducks reared on an intensive system compared with ducks from an extensive rearing system. 相似文献
Difficulties with the direct antiglobulin test (DAT) and its apparent lack of sensitivity and specificity for immune‐mediated hemolytic anemia (IMHA) in dogs have raised skepticism regarding its diagnostic value.
Objective
To compare different DATs and other hematologic parameters in dogs.
Animals
Anticoagulated blood samples from 59 nonanemic and 46 anemic dogs (± IMHA) from a research colony and veterinary clinics.
Methods
Prospective observational study: Immunochromatographic strip, gel microcolumn, and capillary techniques were compared with standard microtiter DAT using 2 polyvalent antiglobulins. Spherocytosis, autoagglutination, osmotic fragility, and clinical data were assessed.
Results
Blood samples from all 59 nonanemic dogs were DAT‐. Among 46 anemic dogs, 33 were suspected of IMHA, but only 20 were DAT+. Old and new DAT methods yielded comparable and consistent results even after storage of chilled blood samples for 1 week. Spherocytosis and autoagglutination (that did not persist after washing) were noted in 15 and 16 DAT+ dogs, respectively. The other 26 anemic dogs, including 21 previously transfused dogs and 4 with autoagglutination, tested DAT‐ by the other methods. Osmotic fragility was increased in 70% (19/27) of anemic and all 15 DAT+ dogs tested. Limited follow‐up testing revealed DAT+ results for 3–70 days.
Conclusions and Clinical Importance
The novel strip and capillary DAT methods are promising adjunct in‐clinic tools. Despite prior immunosuppressive treatment and presence of autoagglutination, the DAT was positive in anemic dogs with IMHA. Transfusion did not cause false DAT+ results. Our results support DAT as a cornerstone in the diagnosis of canine IMHA. 相似文献
A laser method based upon carbon ion implantation and pulsed laser melting of copper has been used to produce continuous diamond thin film. Carbon ions were implanted with ion energies in the range of 60 to 120 keV, and doses of 1.0 x 10(18) to 2.0 x 10(18) ions cm(-2). The ion-implanted specimens were treated with nanosecond excimer laser pulses with the following parameters: energy density, 3.0 to 5.0 J cm(-2); wavelength, 0.308 microm; pulse width, 45 nanoseconds. The specimens were characterized with scanning electron microscopy (SEM), x-ray diffraction, Rutherford backscattering/ion channeling, Auger, and Raman spectroscopy. The macroscopic Raman spectra contained a strong peak at 1332 cm(-1) with full width at half maximum of 5 cm(-1), which is very close to the quality of the spectra obtained from single-crystal diamond. The selected area electron diffraction patterns and imaging confirmed the films to be defect-free single crystal over large areas of up to several square micrometers with no grain boundaries. Low voltage SEM imaging of surface features indicated the film to be continuous with presence of growth steps. 相似文献
The Burdekin Delta is a major irrigation area situated in the dry tropics of North Queensland. It is unique in that (i) it overlies shallow groundwater systems that serve as a major water supply for the irrigation of sugarcane, and (ii) it is adjacent to the world heritage listed Great Barrier Reef. Water management practices include large recharge pits and surface spreading of water to assist with replenishment of the groundwater. This has been useful in maintaining groundwater levels to help control seawater intrusion. This technique, however, can be costly and ineffective in unconfined aquifer systems, which are subjected to large amounts of groundwater pumping for irrigation. There are more than 1800 production bores currently used for irrigation in the Burdekin Delta and the large volumes of water extracted have at times lowered the regional water tables and made it difficult to control seawater intrusion. 相似文献