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31.
Seguin BE Zhang TQ Buoen LC Weber AF Ruth GR 《Journal of the American Veterinary Medical Association》2000,216(1):65-67
OBJECTIVE: To determine prevalence of Holstein bulls with chromosomal anomalies, particularly the 1/21 centric fusion (CF), at a commercial artificial insemination (AI) company in the United States. DESIGN: Cross-sectional cytogenetic prevalence study. ANIMALS: All 606 Holstein bulls at a commercial AI company were cytogenetically screened to detect CF, chimerism, and other chromosomal abnormalities. PROCEDURE: Lymphocytes from heparinized blood samples were cultured by standard cytogenetic techniques, and chromosome spreads were prepared for microscopic examination. Chromosomal abnormalities were detected by examining 10 chromosome spreads per bull. Pedigree analysis was performed. RESULTS: None of the bulls had any type of CF. However, 6 bulls were identified as chimeras (i.e., contained lymphocytes with male [XY] and female [XX] chromosomes). One bull was sire or maternal grandsire to 85 of the bulls tested, and 739 of 1,212 (61%) sire and maternal-grandsire possibilities were accounted for by just 18 bulls. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of these results supports previous indications that CF is extremely rare in Holstein bloodlines available commercially via AI in the United States. However, chimeric bulls are more common, and they reportedly have decreased reproductive performance. Therefore, identification of chimeric sires in the AI facility reported here and the possibility of de novo onset of CF at any time indicates that early cytogenetic screening should be encouraged for prospective bulls intended for use in AI programs. 相似文献
32.
F. Tanno U. Weber Ch. Wacker L. Gaschen V. Schmid J. Lang 《The Journal of small animal practice》1998,39(9):432-436
Ultrasonography was used to compare adhesions induced by two different methods of gastropexy in 16 dogs. An incisional gastropexy technique was used in eight dogs (group 1) and a 'modified' gastropexy technique in the remaining eight (group 2). The length and thickness of the gastropexy and the peristaltic activity of the stomach were measured ultrasonographically and compared between groups. Measurements for the two groups were taken in the early postoperative interval (two to four days), intermediate postoperative interval (eight to 20 days) and late postoperative interval (57 to 79 days). Both techniques were equally successful in forming permanent adhesions at two months postoperatively and there was no recurrence of gastric dilatation and volvulus. The length and thickness of the gastropexy were similar for both groups at two months postoperatively and there were no surgical complications with either technique. The modified gastropexy provides a technique that can easily be performed by a single surgeon , with no increased operative time or duration of anaesthesia, and with the formation of a permanent adhesion. 相似文献
33.
ULTRASONOGRAPHIC DETECTION OF ADRENAL GLAND TUMOR AND URETEROLITHIASIS IN A GUINEA PIG 总被引:1,自引:0,他引:1
Lorrie Gaschen DVM Cornelia Ketz Dr. med. vet. Johann Lang Dr. med. vet Urs Weber Dr. med. vet. L. Bacciarini Dr. med. vet. Ingrid Kohler med. vet. 《Veterinary radiology & ultrasound》1998,39(1):43-46
A 5-year-old guinea pig was presented to the University of Berne Small Animal Radiology Department for an ultrasound examination of the abdomen to confirm a suspected diagnosis of Cushing's syndrome. The patient had bilateral alopecia, was apathic and obese. Ultrasonographically, a tumor of the left adrenal gland, obstruction of the left ureter by an ureterolith, as well as hydronephrosis of the left kidney were detected. During surgery to relieve the ureteral obstruction the adrenal gland tumor was removed. The guinea pig died post-operatively due to blood loss. The left adrenal gland tumor was found histopathologically to be an adenoma and the right adrenal gland also had multiple small adenomas, but grossly appeared normal. The ureterolith was analyzed and found by x-ray diffraction to consist of calcium carbonate. 相似文献
34.
Weber 《Forstwissenschaftliches Centralblatt》1904,26(11):621-629
Ohne Zusammenfassung 相似文献
35.
Heinrich Wilhelm Weber 《Forstwissenschaftliches Centralblatt》1922,44(6):214-224
Ohne Zusammenfassung 相似文献
36.
37.
T. Weber 《Journal of pest science》1964,37(4):59-60
Ohne Zusammenfassung 相似文献
38.
39.
Trutz Weber 《Journal of pest science》1965,38(2):26-26
Ohne ZusammenfassungHerrn Professor Dr. F. Schwerdtfeger zum 60. Geburtstag gewidmet. 相似文献
40.
Guillermo Cabrera Walsh Anthony S. Dimeglio Ashot Khrimian Donald C. Weber 《Journal of pest science》2016,89(1):21-29
Harlequin bug (Murgantia histrionica) is an important pest of cole crops in the USA. The adults and nymphs feed on aboveground plant tissues by sucking cell contents and can seriously damage the host. Current insect control measures on cole crops target mainly lepidopteran pests, and the insecticides generally used do not control harlequin bug, so alternative management practices need to be explored. Previous research has established the existence of a male-produced pheromone attractive to both sexes and nymphs of M. histrionica. In this work, two systems of marking bugs were tested to verify if the mark affected fitness traits such as survival and host location. In a second phase, marked individuals were placed on trap host plants baited with synthetic pheromone lures to test whether migration rates were related to M. histrionica density on the trap plants and the presence of the attractants. Neither marking system affected the survival or orientation of the subjects compared to unmarked individuals. The pheromone lures significantly increased the attractiveness of the trap plants, but did not increase the retention time of the plants compared to unbaited plants. Emigration from the trap plants showed a constant rate and seemed unrelated to bug density on the plants. However, a mean peak density of ca. 36 bugs/plant was calculated. Beyond this number, density tended to decrease. These successful marking methods and retention time models support development of M. histrionica management with trap crops, by providing tentative control thresholds and decision rules. 相似文献