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1.
AR RABIEE KL MACMILLAN F SCHWARZENBERGER D THALLER MJ RATHBONE TE TRIGG 《Australian veterinary journal》2001,79(10):690-694
OBJECTIVE: To evaluate the potential of an implant of a GnRH-agonist (deslorelin) to create a progesterone free animal suitable for studying progesterone (P4) metabolism in intact cows by measuring blood P4 and faecal P4 metabolites. METHODS: Experiment 1: Eighteen non-lactating cycling Holstein-Friesian cows, 4 to 7 years old, were allocated to one of three groups to study plasma P4 concentrations preceding an intravaginal insert. These groups comprised: i) a deslorelin group (GnRH-agonist implanted); ii) a PGF group receiving two injections of prostaglandin (PGF2alpha) 12 days apart; and, iii) an ovariectomised (OVX) group. An intravaginal device (CIDR) was inserted into the vagina of each animal and left in place for 11 days. Plasma P4 concentrations were measured during the study period. Experiment 2: Twelve non-lactating cycling Holstein-Friesian cows, 4 to 7 years old, were allocated to two groups: i) a deslorelin group (GnRH-agonist implanted); and ii) an ovariectomised group. Plasma P4 and faecal P4 metabolites (20-oxo-pregnanes, 20alpha-OH and 20beta-OH) were monitored for a period of 5 weeks. RESULTS: Experiment 1: Average plasma P4 concentration did not differ between the three groups (1.28, 1.43 and 1.55 ng/mL for deslorelin, OVX and PGF cows, respectively, P = 0.8) during the period of supplementation. Experiment 2: There was no difference in plasma P4 (mean plasma P4 < 0.02 ng/mL, P = 0.9) and faecal P4 metabolites between deslorelin and OVX cows 2 weeks after the implantation (P = 0.7). CONCLUSIONS: These data showed that a GnRH-agonist (deslorelin) implant may be used as an alternative to ovariectomy to create a progesterone free animal suitable for studying the metabolism of administered P4. 相似文献
2.
The average passage time, the rumen fluid volume and the digestibility of the organic matter were determined in addition to 3 individual feeding experiments with fertility oriented crossbreed ewes, which received pelleted straw-concentrate mixtures. The average passage time of the feed particles through the digestive tract is shorter in pregnant animals than in lactating ones. It is longest in non-pregnant sheep. High quotas of straw and coarse particles prolong the passage time, increasing feed intake and supplements of long straw shorten it. The volume of rumen fluid is lower in ewes fed ad libitum in the stage of late pregnancy and after lactation than during lactation. The rumen fluid volume is also lower in restrictively fed animals during the stage of late pregnancy than during lactation. In animals in the stage of late pregnancy it correlates negatively with the weight of the litter. On an average of all experiments at maintenance level the digestibility of the organic matter in ewes in the 4th month of pregnancy gravidity amounted to 56.6%, in the 2nd month of lactation to 59.8% and in wethers to 59.5% Due to an increase of energy intake from maintenance to 2. maintenance digestibility of the straw-concentrate mixture with 40% straw decreased by 5.5 units and of that with 60% straw by 17.8 units in the period before delivery. Pregnancy in the 4th month resulted in a digestion depression of between 3.0 and 5.8 units. 相似文献
3.
4.
1118 Friesian cows and 101 Friesian heifers were investigated in internal pelvic measurements and their relationships to external measurements. The mean of the pelvic vertical and the medium diagonally diameter of the pelvis are 19.8 cm and 18.3 cm. 363.9 square centimetres and 76.3 centimetres were found for the pelvic surface and pelvic circumference. The difference between the biggest and smallest pelvis was 295.0 square centimetres. Medium to high coefficiences of correlation were detected between the internal pelvic measurements but relationships between internal and external pelvic measurements were low. From determined external pelvic measurements only the hip breadth provides usefull informations of the pelvic shape. 相似文献
5.
Hoffmann WE Dorner JL Morris H 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1983,12(2):33-38
Antiserum directed against equine intestinal Alkaline Phosphatase (ALP) was produced in rabbits and used to develop a sensitive and quantitative assay for the detection of intestinal ALP in equine serum. This assay was then used to measure the half-life of intravenously injected intestinal ALP and to determine if the intestinal ALP was present in normal horse sera, sera from horses presented for lesions not involving the gastrointestinal tract and sera from horses presented with lesions involving the gastrointestinal tract. The results suggest that intestinal ALP is not likely to appear in equine serum even when gastrointestinal disease is present and, therefore, appears to be of no diagnostic value. 相似文献
6.
A simple and reliable method for the determination of progesterone in milk fat by radioimmunoassay has been developed. Application of the assay under field conditions has shown that all samples diagnosed " questionable" in the former milk progesterone test (MPT) could be characterized as positive or negative. Thus the total figure of animals daignosed correctly rose from 72.3% to 85.8%. The borderlines (ng progesterone / 10 mcl milk fat) set up for this assay were (1) pregnant and (1) nonpregnant (Day 20) and (.3) in estrus and (.3) not in estrus ( Day 0). Within the application for diagnosis of pregnancy, 81.4% were diagnosed correctly as pregnant while 96.3% were diagnosed correctly as not pregnant. The latter figure is somewhat lower than in the MPT (100%), but under the practical conditions the error lies within the range of false diagnosis due to problems with sample identification. 相似文献
7.
H Hoffmann 《DTW. Deutsche tier?rztliche Wochenschrift》1990,97(1):24-26
A Pig Health Service in Bavaria was established in 1958, there was one veterinary-officer working. The department Pig-Health Service of the "Tiergesundheitsdienst Bayern" has twenty-one veterinary-officers now. They mostly are working in the pig health scheme, doing stress susceptibility test, giving advice and expert evidence. 相似文献
8.
Neural lesions of Marek's disease, Marek's disease tumours in the ovary, liver, and kidney, as well as spleen and bursa of Fabricii of chickens bearing Marek's disease tumorous infiltrations, were examined by a new immunohistochemical technique basing upon Sternbergers unlabelled antibody enzyme method which allows the exact localization of lymphoid cells based on their surface antigens. Type C neural lesions contained T-lymphocytes almost exclusively. Type B neural lesions had relatively high proportions of T- and B-lymphocytes, and severe type A neural lesions possessed one part of heavily labelled T-lymphocytes and a number of cells stained weakly by rabbit-anti-chicken-T-cell-globulin. Tumorous infiltrations had similar characteristics as type A neural lesions. Spleen and interfollicular spaces of bursa of Fabricius were infiltrated by T-lymphocytes. 相似文献
9.
10.
Olga Seco Diaz MRCVS Anne Desrochers DMV Vickie Hoffmann VMD Virginia B. Reef DVM 《Veterinary radiology & ultrasound》2005,46(1):83-85
An 8-day-old Arabian-Morgan cross colt underwent cardiac evaluation. The foal was tachycardic, tachypneic, exercise intolerant and had a loud right-sided heart murmur and cyanotic mucous membranes. Total anomalous pulmonary venous connection was diagnosed with echocardiography and confirmed at postmortem examination. Total anomalous pulmonary venous connection is a very rare congenital cardiac abnormality that has not been reported before in the horse. 相似文献