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11.
Pigeon circovirus was identified by polymerase chain reaction (PCR) in young pigeons belonging to 12 different lofts. Viral DNA was extracted from formalin-fed, paraffin-imbedded tissues containing primarily bursa and occasionally liver and spleen with a commercial kit. PCR primers were selected from a published sequence for columbid circovirus and evaluated in a PCR assay. The histopathologic examination of various tissues revealed basophilic globular intracytoplasmic inclusions in the mononuclear cells of the bursa of Fabricius and occasionally in the spleen characteristic for a circovirus. Transmission electron microscopy of a few bursas of Fabricius revealed virus particles measuring 18-21 nm. All the samples were negative by PCR for psittacine beak and feather disease (PBFD) virus and chicken infectious anemia virus. The primers for both pigeon circovirus and PBFD virus did not react in PCR with the chicken anemia virus DNA. Most of the circovirus-infected pigeons had concurrent infections of Escherichia coli, Salmonella, Pasteurella, Aspergillus, candidiasis, nematodiasis, or capillariasis. 相似文献
12.
This preliminary study investigated the potential role of staphylococcal superantigens in the pathogenesis of canine pyoderma. The staphylococcal enterotoxins A (SEA), SEB, SEC and SED, and the toxic shock syndrome toxin-1 (TSST-1) were assayed in isolates from skins of dogs with pyoderma. Culture supernatants from 25 of 96 isolates were positive for multiple superantigens, with SEA and SEC being the most frequently detected. In in vitro stimulation of canine peripheral blood mononuclear cells and quantitative flow cytometry revealed that low concentrations of SEA and SEB were potent stimulators of blastogenesis of T cells. 相似文献
13.
Serum immunoglobulin G (IgG) responses of healthy dogs and dogs with Malasseziapachydermatis dermatitis were compared by Western immunoblotting. M pachydermatis CBS 1879 was disrupted mechanically and its proteins were separated and blotted on to nitrocellulose membranes before being incubated with sera from eight healthy beagles, eight Irish setters with gluten-sensitive enteropathy, 15 healthy basset hounds, and 30 dogs with Mpachydermatis-associated dermatitis, 20 of which were basset hounds. The mean (se) numbers of bands of immunoreactivity observed in the seborrhoeic basset hounds (10.7 [0.4]) and affected mixed-breed dogs (9.4 [0.9]) were significantly greater than in the beagles (3-0 [1.0]), Irish setters (5.5 [1.1]) and healthy basset hounds (5.6 [0.7]). The number of bands identified was correlated (r(s) = 0.76, P < 0.001) with the anti-M pachydermatis IgG values measured by ELISA in a previous study. Most of the dogs were immunoreactive towards the 132, 66 and 50 to 54 kDa proteins and the affected dogs were also usually reactive towards the 219, 110, 71 and 42 kDa proteins. 相似文献
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Quantification of pork belly and boston butt quality attribute preferences of South Korean customers
Vonada ML Bidner BS Belk KE McKeith FK Lloyd WR O'Connor ME Smith GC 《Journal of animal science》2000,78(10):2608-2614
U.S. packers must have quantitative criteria for selection of pork bellies and Boston butts for export to South Korea. Pork bellies (IMPS 409A) and Boston butts (IMPS 409A, 406B, 407) were selected from normal production in a U.S. pork packing plant and transported to Seoul, South Korea, via seafreighter in refrigerated containers (frozen < -5 degrees C) or via air freight (fresh > 0 degrees C; frozen < -5 degrees C). Participants at the Seoul Food Show were surveyed about their preferences for specific quality attributes of these cuts. Bellies were selected to differ in seam fat content (low = < 20%, moderate = 20 to 40%, high = > 40% extractable fat), lean color (pale = L* > 50, medium = L* 48-50, dark = L* < 48), weight (3.36, 4.04, or 5.36 kg), state of refrigeration and packaging (frozen, poly-wrapped; chilled, poly-wrapped; frozen, vacuum-packaged; chilled, vacuum-packaged), shape (round, wavy, square), and belly thickness (3.81, 4.32, or 4.90 cm). Boston butts were selected to differ in USDA marbling score (Slight, Small, Modest, Moderate, and Slightly Abundant), seam fat content (low = < 10%, moderate = 10 to 20% fat, high = > 20% extractable fat), lean color (pale = L* > 44, medium = L* 40-42, dark = L* < 38), weight (2.91, 3.82, or 4.66 kg), state of refrigeration and packaging (frozen, poly-wrapped; chilled, poly-wrapped; frozen, vacuum-packaged; chilled, vacuum-packaged), and shape (square, oblong, round). In Seoul, pork subprimals were tempered (if frozen), sliced, and arrayed by quality attribute and category in a retail display case. Over 4 d of testing, attendees (n = 210) of the food show were asked to rate the displayed samples for each quality attribute on a standardized ballot. Mid-weight (3.82 kg) Boston butts that displayed Moderate or higher USDA marbling scores with moderate amounts of seam fat, Japanese lean color scores of 2 or 4, round geometric shape, and that were vacuum-packaged and transported to Korea in the freshly chilled state best characterized the quality attribute preferences of respondents. Pork bellies that exhibited moderate amounts of seam fat, Japanese lean color scores of 3, square shape, belly thickness of 3.94 cm, approximate weight of 4.04 kg, and that were vacuum-packaged and transported to Korea in the freshly chilled state best met the quality needs of South Korean customers. 相似文献
17.
Lloyd S Smith J Connan RM Hatcher MA Hedges TR Humphrey DJ Jones AC 《The Veterinary record》2000,146(17):487-492
One hundred and fifty horse owners, primarily private owners and riding schools, replied to a questionnaire concerning the practices they used to control parasites. Twenty-seven had experienced a parasite problem. Faecal samples from 188 horses selected at random showed that worm control practices were generally successful; however, many owners were not following recommendations for slowing the development of resistant parasites. In 1996, 86 per cent of the owners were using either three or two classes of anthelmintic a year, and they used a median of six doses with a range from one to 11. Approximately half the owners, more commonly owners of up to five horses, picked up their horses' faeces at least once a week, but these owners also used more doses of anthelmintic a year than owners who did not pick up faeces. One-third of the owners manually removed Gasterophilus species eggs from the horses' hairs, but 94 per cent of them also used ivermectin. Many owners treated specifically for Anoplocephala species, cyathostome larvae and Gasterophilus species, and these owners were the most likely to use three classes of anthelmintic a year. One-hundred-and-seven owners replied to a second questionnaire asking for information about the factors that influenced their anthelmintic control practices. Many owners, particularly private owners, were not influenced by the cost of the anthelmintic. For the timing and frequency of treatment, and the choice of drug, owners were most influenced by advertisements, magazine articles and veterinary surgeons. In two magazines aimed at horse owners, the brands of drugs most frequently advertised were the brands most commonly used by the owners, and articles in the magazines recommended the use of three classes of drug per year. These results are discussed in relation to their influence on the development of anthelmintic-resistant nematodes. 相似文献
18.
Johnson-Ifearulundu YJ Kaneene JB Sprecher DJ Gardiner JC Lloyd JW 《Preventive veterinary medicine》2000,46(3):171-181
A prospective cohort study design was used to evaluate the impact of subclinical Mycobacterium paratuberculosis infection on days open in a sample of Michigan dairy herds with a history of cows positive for M. paratuberculosis diagnosed by fecal culture. Participating herds were tested and productivity and reproduction records were monitored for 18 months. All cows > or = 24 months old were tested for M. paratuberculosis infection using the ELISA and radiometric fecal-culture (RFC) techniques. Test-negative cows were re-tested at the conclusion of the monitoring period. Multivariable regression models were used. Using both tests in parallel, the overall sample apparent prevalence for M. paratuberculosis infection was 41.8% (223/533 animals tested). Adjusting for diagnostic sensitivity and specificity, this resulted in a calculated sample true prevalence of 59.9%. ELISA-positive cows (on average) had a 28-day increase in days open when compared to ELISA-negative cows (p=0.02). The diagnostic method used to define a case altered the apparent association between paratuberculosis test status and days open. Fecal culture was a less-effective diagnostic tool for use in herds with a high prevalence of infected animals. The increase in days open in the ELISA-positive cows was an indication that perhaps reduced estrus expression or an increased post-partum anestrous period occurred in the subclinically infected ELISA-positive animals. This might have been due to a negative energy balance associated with M. paratuberculosis infection. 相似文献
19.
A study was designed to model the fluctuations of nine specific element concentrations in mammary secretions from periparturient mares over time. During the 1992 foaling season, serial samples of mammary secretions were collected from all 18 pregnant Arabian mares at the Michigan State University equine teaching and research center. Non-linear regression techniques were used to model the relationship between element concentration in mammary secretions and days from foaling (which connected two separate sigmoid curves with a spline function); indicator variables were included for mare and mare parity. Element concentrations in mammary secretions varied significantly during the periparturient period in mares. Both time trends and individual variability explained a significant portion of the variation in these element concentrations. Multiparous mares had lower concentrations of K and Zn, but higher concentrations of Na. Substantial serial and spatial correlation were detected in spite of modeling efforts to avoid the problem. As a result, p-values obtained for parameter estimates were likely biased toward zero. Nonetheless, results of this analysis indicate that monitoring changes in mammary-secretion element concentrations might reasonably be used as a predictor of impending parturition in the mare. In addition, these results suggest that element concentrations warrant attention in the development of neonatal milk-replacement therapies. This study demonstrates that non-linear regression can be used successfully to model time-series data in animal-health management. This approach should be considered by investigators facing similar analytical challenges. 相似文献
20.
A juvenile cheetah (Acinonyx jubatus) died with rapidly progressive pyrexia, tachypnea, abdominal effusion, and hepatomegaly. Postmortem examination revealed lesions consistent with acute disseminated infection with Toxoplasma gondii. The presence of this organism was confirmed in multiple organs by immunohistochemistry and polymerase chain reaction. To the best of our knowledge, we propose this to be the first reported case of primary acute disseminated toxoplasmosis in a cheetah. 相似文献