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61.
A rapid and low cost procedure, the carbon immunoassay (CIA) test, was evaluated for the diagnosis of Toxoplasma gondii infections. Using a closely related parasite (Besnoitia jellisoni) as antigen, and homologous or heterologous immune sera, it was demonstrated by light and electron microscopy that CIA is a very reliable and specific test. As it is neither expensive nor time-consuming, it can be recommended for general and routine laboratory use. 相似文献
62.
F. Barr 《The Journal of small animal practice》1992,33(8):359-364
A simple ultrasonographic method of estimating liver size in the dog was evaluated in this study. A single linear measurement from the tip of the ventral liver lobes to the diaphragm was made, using both transverse and longitudinal planes of section, Assuming careful technique, this measurement proved to be highly reproducible. There was good correlation between the measurements taken on the two planes of section. This measurement was shown to provide a good indicator of liver mass, irrespective of the size or breed of dog. It was concluded that ultrasound provides a simple, quantitative method of assessing liver size in the dog. 相似文献
63.
I J Lean R L Baldwin H F Troutt M L Bruss J C Galland T B Farver J Rostami L D Weaver C A Holmberg 《American journal of veterinary research》1992,53(5):731-741
Metabolic and production responses are reported for 72 cows treated with bovine somatotropin (BST) for 30 days starting at day 70 of lactation. Of these 72 cows, 48 had been exposed in the preceding lactation to long-term treatment with BST at 3 dosages and 24 (controls) had not been given BST. Approximately half of the cows in each group were parity-2 cows, the rest were older. Comparisons between groups were made separately for parity-2, and older cows. Analyses, using pretreatment values of each variable as a covariate, indicated that older cows, but not parity-2 cows, significantly (P less than 0.05) increased milk production during treatment. Parity-2 cows, however, had a significantly higher milk fat percentage than controls following treatment. Cows treated with 51.6 or 86 mg BST/d in both parity groups had significantly higher serum-free fatty acids than controls. Estimated net energy balances were significantly lower for older treated cows, but did not significantly differ from controls for parity-2 treated cows. Older cows in the 86 mg of BST/d group tended to have higher concentrations of blood glucose than did older control-group cows. Treatment with BST did not significantly increase serum ketone concentrations in any group of animals, and none of the cows developed clinical ketosis during this period. Estimated net energy balance (ENEB) during treatment was a significant (P less than 0.05) covariate for free fatty acid concentrations in older cows and for milk fat percentage in parity-2 cows. Covariate adjusted analyses, using ENEB during treatment as a covariate, indicated that lipolytic stimuli already acting may be enhanced by treatment with BST, but a negative energy balance was not a necessary precondition for free fatty acid concentrations to increase following somatotropin treatment. Similarly, milk fat percentages for parity-2 treated cows were significantly (P less than 0.05) higher during treatment than controls when ENEB during treatment was used as a covariate. Increased milk fat concentrations in parity-2 treated cows were not associated with significant increases in the ratio of C18:C4-10 milk fatty acids, indicating that increased milk fat resulted from either an increase in incorporation of C18 fatty acids into milk fat coupled with an increase in de novo mammary synthesis of C4-10 milk fatty acids or an increase in C12-16 fatty acids that may arise either from increased tissue mobilization, from diet, or from de novo mammary synthesis. 相似文献
64.
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
65.
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
66.
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
67.
Duration of maternal immunity to peste des petits ruminants 总被引:1,自引:0,他引:1
68.
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
69.
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
70.
G S Smith K K Rozman D M Hallford D L Rankins M F Khan 《Journal of animal science》1989,67(1):187-195
Recently we reported elimination of radioactivity from [14C]heptachlor from body stores of lactating ovines, mainly into excreta rather than milk, contrasting sharply with bovines. To further assess heptachlor metabolism and clearance by ovines, 12 fine-wool wether lambs (41 +/- 3 kg) housed in metabolism stalls were fed pelleted alfalfa hay (96%) plus molasses (3%) ad libitum and were dosed i.p. once with [14C]heptachlor (1.643 mg/kg body wt; sp. act. = .89 microCi/mg). Feces and urine were collected separately and quantitatively. Light mineral oil was mixed with feed (5 g/100 g) of six lambs and trans-stilbene oxide, an inducer of biotransformational enzymes, was administered i.p. (4 g/hd initially; 2 g/hd daily thereafter) through 20 d to three lambs given each mineral oil treatment, in 2 x 2 factorial arrangement. Feces, urine, blood, bile and body tissues were assayed for total 14C activity. Radioactivity (heptachlor and [or] metabolites) eliminated into excreta during 21 d amounted to 34 to 36% of dose administered, of which 67% appeared in urine and 33% in feces. Biological half-time for elimination into excreta was 11.3 d [Kel = -.061/d], similar to 11.7 d we reported for lactating ewes. Clearance from blood had T1/2 = 14 d. Neither mineral oil nor trans-stilbene oxide altered rate or route of 14C activity excreted or concentrations of 14C activity in blood. Results confirmed that ovines eliminate heptachlor much more rapidly than bovines. 相似文献