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131.
With the help of a new synthetic material follicles and corpora lutea from the ovaries of 80 cows in different stages of the sexual cycle were examined for modifications of their blood vessel architecture. In the theca externa the main artery which runs towards the follicle, separates into arterioles of which capillaries derive in the theca interna, building a basket-like network around the zona granulosa. After ovulation the follicle wall forms characteristic fields. Capillaries grow into the zona granulosa and thus the folds form the lobular structure of the corpus luteum. Capillaries which rise from the ruptured part of the follicle, spread centripetally and together with lutein cells they build up the not lobulated cupola of the corpus luteum. The regression of the corpus luteum starts around the 16th day of the cycle, beginning at the capillary network of the cupola. A contraction of the vessels and a quick decrease of the volume follow. 相似文献
132.
In mid-September, 1 month before the insertion of intravaginal pessaries to induce sexual activity, blood samples were collected every 4 days from 16 ewe lambs aged 7 months, in order to determine the incidence of ovulations by measurement of plasma progesterone concentrations. It has been studied whether the response to a progestagen treatment of ewe lambs apparently close to puberty could be modified by the onset of the ovarian events preceding puberty. The effect of the presence or absence of ovulations prior to progestagen treatment on the potential reproductive performance (fertility, litter size and fecundity), embryo development [embryo quality and interferon-tau (IFNτ) secretion], luteal function (progesterone secretion in vitro ) and endometrial progesterone content was studied in seven ovulating (Ov+) and nine nonovulating ewe lambs (Ov−) on day 14 after mating. The best potential reproductive results were obtained with Ov+ animals, although these differences could not be initially attributed to either different progesterone secretion in vitro or concentration of endometrial progesterone. Irrespective of the experimental groups, secretion of progesterone by luteal tissue from ewe lambs with normal embryos was significantly greater (p<0.05) than that of animals with abnormal embryos or with no embryos. Normal embryos secreted a higher amount of IFN-τ than those embryos classified as abnormal (p<0.07). In conclusion, ewe lambs which exhibit luteal activity before puberty have the highest levels of reproductive performances after a progestagen treatment. Corpora lutea from ewe lambs with normal embryos had higher rates of progesterone secretion in vitro and their embryos had a higher IFN-τ production by the embryos, indicating greater capacity for subsequent development. 相似文献
133.
Meat regulations also involve game inspection. This publication deals with the regulations concerning furred game intended for slaughter and furred game hunted for food. 相似文献
134.
The sera of 188 lambs from seven breed groups were analyzed for the concentrations of IgG1, IgG2, IgM and IgA by radial immunodiffusion using monospecific antibodies. From each lamb, 14 blood samples were drawn before and 5 samples after weaning. The following results were obtained: 1. Immunoglobulins could not be detected in sera drawn before the first intake of colostrum. 2. In normally suckling lambs, the peak concentrations of maternal immunoglobulins are attained at 0-18 hrs after birth. They can be assessed in a single blood sample drawn between 18 and 24 hrs. 3. The half-life times of maternal immunoglobulin in lamb sera are 11 days for IgG1, 7 days for IgG2, 6 days for IgM and 18 hours for IgA. 4. The absolute peak heights relate to the amounts of colostrum ingested before 12-18 hrs after birth. 5. The decline of maternal immunoglobulins in lamb sera over-laps with the onset of lamb immunoglobulin synthesis. Renewed rises of concentrations are observed for IgG2 after week 2, for IgM after week 3 and for IgG1 after week 7. The concentrations of IgA remain at the low levels characteristic for the serum of grown sheep. 6. The role of immunoglobulin synthesis in suckling lambs is only briefly and to a small extent reduced after weaning. 相似文献
135.
Duration of maternal immunity to peste des petits ruminants 总被引:1,自引:0,他引:1
136.
K S Rogers E B Janovitz S K Fooshee P F Steyn K E Frankum 《Journal of the American Veterinary Medical Association》1989,195(9):1242-1244
Lymphoblastic lymphosarcoma with disseminated skeletal involvement was diagnosed in a 15-week-old Golden Retriever. The skeletal disease was characterized by diffuse, irregular areas of radiolucency most evident in the diaphyseal portion of long bones and was associated with gait abnormalities and signs of pain. Necropsy also revealed involvement of the spleen, liver, kidneys, and mesenteric lymph nodes. 相似文献
137.
The objective of this study was to compare rebreeding activities of spring- vs fall-lambing Polypay, Dorset, St. Croix and Targhee ewes that either suckled their lambs for 40 d or had lambs weaned at birth. Seasonal effects of male fertility were reduced by utilizing an excess number of fertile rams in the spring. Plasma concentrations of progesterone were monitored to assess days to the first normal ovulation, days to conception and estrous vs anestrous activity. Breed, season and lactation affected the rebreeding performance. Dorset ewes had similar conception rates between spring and fall but a shorter interval from lambing to first ovulation in the fall. Polypay and Targhee ewes were the opposite; they had higher conception rates in fall than in spring matings with no seasonal influence on postpartum interval. Postpartum ewes in the fall had higher conception rates, and fewer of these ewes became anestrous or had estrous cycles of abnormal duration than of those ewes lambing in the spring. Ewes that suckled for 40 d in the spring had delayed estrous activity, but when these ewes became estrual they had higher conception rates than ewes whose lambs were weaned at birth. Lactation had no inhibitory affect on the postpartum interval of fall lambing ewes. These data suggest that the response of different breeds to various components of postpartum fertility varies with season and management of the flock. 相似文献
138.
K Fehlhaber G Krüger V Schubert H Rolletschek 《Archiv fuer experimentelle veterinaermedizin》1989,43(6):855-862
Reference is made to work undertaken by Stehle (1983) on rapid semiquantitative determination of urinary protein in pigs for slaughter to identify premortal strain and stress, with additional studies being conducted into the suitability of the method. The investigations performed for this study covered urinary protein samples from 59 living and 762 slaughtered pigs. The Biophan E paper strip test was applied to groups of animals, and, when compared to high-accuracy laboratory determination of urinary protein, it provided sufficiently accurate information on the presence of stress-related proteinuria. Its accuracy, however, proved to be insufficient, when individual animals were examined. The number of clearly stressed slaughter pigs was unexpectedly high, although the same animals had been rated clinically inconspicuous prior to slaughter. Brief rest period resulted in significant rise of stress. The Biophan E paper strip test was found to be suitable for instantaneous determination of stress and strain on pigs for slaughter. 相似文献
139.
Hemagglutination and hemagglutination inhibition of turkey red blood cells with Mycoplasma hyopneumoniae 总被引:2,自引:0,他引:2
T F Young B Z Erickson R F Ross Y Wannemuehler 《American journal of veterinary research》1989,50(7):1052-1055
The ability of Mycoplasma hyopneumoniae to agglutinate RBC was evaluated to develop an in vitro cytadsorption assay. Using swine RBC in a microtitration hemagglutination test, no agglutination or partial agglutination was detected. Comparison of RBC from various other species indicated that improved hemagglutination was obtained with RBC from turkeys. This hemagglutination was detected only when mycoplasma cells used in the assay had been frozen and thawed, heated at 50 C for 30 minutes, or treated with trypsin. Treatment of RBC with trypsin or neuraminidase enhanced hemagglutination. Possible surface lectin activity in M hyopneumoniae was evaluated by use of carbohydrates in a blocking assay; hemagglutination was not inhibited by any of 13 carbohydrates evaluated. Mycoplasma hyopneumoniae convalescent porcine serum and monoclonal antibodies against 2 M hyopneumoniae immunogens of molecular weights of 64,000 and 41,000 inhibited hemagglutination. 相似文献
140.
Chicken anemia agent in the United States: isolation of the virus and detection of antibody in broiler breeder flocks 总被引:4,自引:0,他引:4
Chicken anemia agent (CAA) was isolated from broiler chickens in Texas with a blue wing or anemia dermatitis-like syndrome. Specific-pathogen-free chicks inoculated with field material developed anemia, and CAA was isolated in MDCC-MSB1 cells from bone marrow and lymphoid tissue from inoculated chicks. One isolate, designated EF88/78/276, was further characterized. Infectivity of EF88/78/276 was resistant to treatment with chloroform and with heat at 70 C for 5 minutes. EF88/78/276 was indistinguishable from the Cux-1 and Gifu-1 isolates of CAA by cross-neutralization tests. Almost all 1-day-old susceptible chicks inoculated intramuscularly with EF88/78/276 developed anemia, but contact-infected chicks did not. Antibody to CAA was detected in broiler breeder flocks from Texas, the Delmarva peninsula, and Alabama. 相似文献