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31.
Crossbred progeny sired by either Duroc or Pietrain boars, normal for the ryanodine receptor gene, were evaluated for carcass composition and meat quality. Boars from each breed were mated to Yorkshire or F1 Yorkshire-Landrace females. A total of 162 off-spring was evaluated for carcass and meat quality traits at a common age (approximately 26 wk of age). Duroc-sired progeny had heavier (108.0 vs. 103.0 kg, P < 0.001) and longer carcasses (86.9 vs. 84.8 cm, P < 0.01), whereas Pietrain-sired pigs had less backfat at the first rib (44.6 vs. 47.7 mm, P < 0.01), last lumbar vertebrae (20.9 vs. 23.0 mm, P < 0.05), and 10th rib (23.0 vs. 25.5 mm, P < 0.01). No difference between Pietrain and Duroc progeny was detected for fat depth at the last rib (27.8 vs. 28.8 mm, respectively). Pietrain progeny had a higher percentage of lean at slaughter (52.6 vs. 50.7, P < 0.05) and higher dressing percentage (74.0 vs. 73.1, P < 0.01). Primal cut weights were collected with Pietrain progeny having a greater percentage of carcass as ham (23.0 vs. 22.4, P < 0.01) and loin (21.6 vs. 21.2, P < 0.05), whereas Duroc progeny had a higher percentage of belly weight (12.0 vs. 11.7, P < 0.05). Percentages of Boston butt (8.8 vs. 9.0) and picnic shoulder (9.9 vs. 9.9) were similar for Duroc vs. Pietrain progeny. Total weight of these five primal cuts, as a percentage of carcass weight, was higher for Pietrain progeny (75.2 vs. 74.3, P < 0.01). With heavier carcass weight, Duroc progeny had greater primal cut weights as a function of age. Subjective meat quality scores for color, marbling, and firmness (1 to 5 scale) were more favorable for Duroc-sired progeny. Furthermore, chops from Duroc progeny had higher 24-h pH (5.53 vs. 5.48, P < 0.001) and Minolta a* (17.33 vs. 17.04, P < 0.05) with less percentage drip loss (2.88 vs. 3.80, P < 0.001). No differences were detected between Duroc- and Pietrain-sired progeny for Minolta L* (54.77 vs. 55.37) or b* (7.58 vs. 7.58) objective color scores, percentage cooking loss (28.63 vs. 29.23), or Warner-Bratzler shear force (6.94 vs. 7.11 kg). Both sire breeds have beneficial traits that can be utilized in commercial pork production and merit further study. 相似文献
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Aspergillosis is a significant cause of mortality in captive penguins (Sphenisciformes). An indirect ELISA for the detection of Aspergillus fumigatus-specific immunoglobulin in penguins was developed and standardised by making use of a family-specific antiserum (anti-Aptenodyptes patagonica patagonicus). The results were calculated quantitatively as ELISA units, derived by polynomial regression analysis, and semi-quantitatively as end titres. Serum samples from 61 captive penguins were tested with the assay, and the results were compared with those obtained by counterimmunoelectrophoresis (CIE). The ELISA results correlated with the CIE results only when end titres were reported (R(s) = -0.676, P < 0.002). Fifty-seven of the penguins (93 per cent) were seropositive, but the detection of immunoglobulin did not correlate with clinical disease. At Whipsnade Wild Animal Park, Humboldt's penguins (Spheniscus humboldti) demonstrated higher seropositivity than king penguins (Aptenodyptes patagonicapatagonicus) (P = 0.022), but Humboldt's penguins at Fota Wildlife Park had a significantly higher seropositivity than Humboldt's penguins at Whipsnade (P = 0.035). 相似文献
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Edwards JF 《Veterinary pathology》2002,39(6):744-746
Three cases of bovine, ovarian epidermoid cysts were diagnosed as unilateral benign lesions in three out of 1,971 cows at slaughter. A stratified, cornifying, and squamous epithelium without associated skin adnexal structures or tissues from other embryonic tissue layers lined the cysts. The cysts were small, usually multiple, and contained keratin debris. Macroscopically, they resembled abscesses. These are benign, congenital lesions that are a separate entity from dermoids and teratomas, and they appear to have a higher incidence in cattle with Bos indicus breeding. 相似文献
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Survival and inactivation of classical swine fever virus 总被引:2,自引:0,他引:2
Edwards S 《Veterinary microbiology》2000,73(2-3):175-181
Classical swine fever virus, like many enveloped viruses, may be regarded as moderately fragile. It shows a short but variable survival time in the environment, depending on physical conditions, but may remain viable for prolonged periods in favourable circumstances as found, for example, in stored meat. Published information is reviewed on the survival time of the virus under a variety of physical and chemical conditions, including the variable influence of environmental factors. The principles of virus inactivation by heat, pH or chemicals are discussed, with a consideration of the principles of containment for laboratories working with the virus. 相似文献
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The western corn rootworm, Diabrotica virgifera virgifera LeConte, is the most important pest of maize in the Midwestern USA, and since its detection in 1992 in Europe, also in several countries of Central and Eastern Europe. Methods for managing this pest vary from region to region, depending upon: the different cultural practices in maize production, climatic conditions, soil types, pest behaviour, infestation level and socio-economic conditions. Factors including date of planting, amount of rotated or continuous maize, irrigation, date of rootworm hatching and differences in behaviour of the pest, necessitate developing different management strategies in different areas of the infested countries. Pest monitoring, damage evaluation, threshold development, use of insecticides, risk estimation and crop rotation are some of the starting points in the development of management strategies. Approaches and experiences in D. v. virgifera control and management in Italy, Hungary and the USA, based on the understanding of local agro-ecosystems and socio-economic conditions, are reported. 相似文献
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