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Treatment test for bovine mastitis by the determination of ATP based on firefly bioluminescence
1989
Kim, T.J. | Kim, J.B. | Lee, S.B. | Jeon, Y.S. (Kunkuk Univ., Seoul (Korea R.). Coll. of Animal Husbandry)
This study was carried out to treatment test for bovine mastitis by the determination of adenosine triphosphate (ATP) based on firefly bioluminescence. In the susceptibility test, cephalothin which looks the most effective were sensitive to Staphylococcus sp. (72.3 %), Micrococcus sp. (84.2 %), Streptococcus sp. (72.7 %) and Gram positive bacilli (72.7 %), Gram negative bacilli were sensitive to gentamycin (92.3 %) and Yeast-like-fungi was the most sensitive to clotrimazole, and nystatin in order. When the number of bacteria, such as Staphylococcus aureus, Candida tropicalis isolated from the mastitis milk were counted by conventional agar plating technique, and compared with the concentration of bacterial ATP, it gave a good linear relationship. The content of ATP per Staphylococcus aureus, cell was 3.1fM and Candida tropicalis showed the high level of ATP (90fM). The ATP assay was applied to the determination of minimal inhibitory concentration (MIC) of various antibiotics. When Staphylococcus aureus was incubated in the presence of different concentration of tetracycline, erythromycin, kanamycin and streptomycin sulfate and the growth was monitored by the conventional agar plating technique and ATP assay, both methods showed the same results that they were 1mcg/ml, 2mcg/ml, 6.25mcg/ml and 8mcg/ml, respectively. For the determination of susceptibility of sensitive and resistant Staphylococcus aureus isolated for the milk with mastitis to tetracycline, erythromycin, kanamycin and strepomycin sulfate, the minimum time required for the test was determined by the assay of ATP every 30 minutes during incubation of 3 hours at 37deg C. ATP concentration time curve calculated on both resistant and sensitive strains incubated 3 hours as the optimum time for the determination of susceptibilities of various antibiotics examed. The ATP concentration of each test brith (antibiotic contraining), expressed as a percentage of its own control brith (antibiotic-free) indicated values of 30 % to be indicative of each antibiotic sensitivity.
Afficher plus [+] Moins [-]Studies on testes development and spermatogenesis in the male duck
1989
Lee, J.H. | Park, Y.S. (Chonnam National Univ., Kwangju (Korea R.). Coll. of Veterinary Medicine)
This study was conducted in order to observe the changes in cellular association of seminiferous tubules from 4 to 22 weeks of age and to obtain the cycle and relative duration of seminiferous epithelia from 24 weeks of age in male ducks. Fifety-five male ducks were used in the experiment and divided into 11 groups, consisting of 5 male ducks each, with 2 weeks intervals from 4 to 24 weeks of age. The body and tests weight showed most rapid increase during 4 to 6 weeks and 18 to 22 weeks of age, respectively. The seminiferous tubules were abruptly enlarged in diameter of tubules during 18 to 22 weeks of age. Gonocytes were seen from 4 to 6 weeks of age, however they were not observed as from 8 weeks of age. Both type Ap spermatogonia and type Ad spermatogonia occurred from 8 to 12 weeks of age, while spermatocytes and spermatids were beginning to appear at 16 weeks and 18 weeks of age, respectively. Spermatozoa were first observed at 20 weeks of age. Full spermatogenic activity was completed at the age of 20 weeks. Average paired weight of the testes in male ducks was 78g at 24 weeks of age and its ratio spermatogenic activity was completed at the age of 20 weeks. Average diameter of seminiferous epithelium at 22 weeks of age was 232 micro m, and average numbers of Sertoli cell, spermatogonia, spermatocyte, spermatids and spermatozoa in the cross section of seminiferous epithelium were 15.30, 59.08, 41.78, 71.11 and 165.30, respectively. Spermatogonia and spermatids were classified into 2 and 4 types, respectively. The cycle of the seminiferous epithelium could be divided into 5 stages at 24 weeks of age. The relative frequencies of stages from I to V were 13.5 %, 25.0 %, 22.3 %, 20.6 % and 18.7 %, respectively. Thus, establishment of spermatogenesis in male ducks were beginning to appear at 20 weeks of age
Afficher plus [+] Moins [-]New trends of vaccine development: Recombinant vaccinia viruses (expression vectors) as vaccines
1989
Kim, U.H. (Kangwon National Univ., Chunchon (Korea R.). Coll. of Animal Agriculture)
The prospect of live vaccines consisting of genetically modified vaccinia virus expressing foreign genes is exciting, but important issues concerning safety and efficacy need to resolved. Vaccinia virus (VV) is an efficient expression vector with broad host range infectivity and large DNA capacity. This vector has been particularly useful for identifying target antigens for humoral and cell-mediated immunity. The WHO smallpox eradication program, involving the extensive use of VV vaccines, resulted in the late 1970s in the elimination of one of the world's most feared diseases. This achievement is a triumph for preventive medicine and for international collaboration in public health. In 1980, WHO recommended that the routine use of smallpox vaccine should be stopped. Against this background, the prospect of live vaccines consisting of genetically modified VV expressing foreign antigens arising from the work of Moss, and Paoletti and their colleagues in 1982 has been greeted with enthusiasm. These investigators have shown that genes coding for immunogenic proteins can be inserted into VV DNA without impairing the ability of the virus to grow in cell culture. Moreover experimental animals infected with VV recombinants containing genes coding for a variety of immunizing proteins have been shown to be protected against challenge infection with the corresponding infectious agent. In this communication, I describe current progress in the construction of a novel plasmid vector that facilitates the insertion and expression of foreign genes in VV as well as the selection of recombinants
Afficher plus [+] Moins [-]Levels of plasma progesterone, estradiol-17-beta and several serum chemical components in recipients at the time of nonsurgical transfer of frozen/thawed bovine embryos
1989
Lee, B.C. | Jo, C.H. | Hwang, W.S. (Seoul National Univ., Suwon (Korea R.). Coll. of Veterinary Medicine)
A total of 13 synchronized dairy cattle (Holstein) were used to determine pregnancy rates in relation to plasma progesterone, estradiol-17-beta levels and serum chemical values on the day of last PGF 2 alpha injection and day of frozen/thawed bovine embryo transfer. The pregnancy rate of recipients with 1.0-4.0ng/ml of progesterone levels at the day of last PGF 2 alpha injection was higher than that of recipients with below 1.0ng/ml or above 4.0ng/ml of progesterone levels. On the day of transfer, optimal progesterone levels were between 1.0ng/ml and 4.0ng/ml coinciding with a pregnancy rate of 88.9 %. Pregnancy rate decreased when progesterone levels were below 1.0ng/ml (33.3 %) or above 4.0ng/ml (0 %). Corpus luteum grade did not affect pregnancy rate and this result revealed that manual palpation of corpus luteum was not valid criterion of corpus luteum function. Progesterone levels as well as pregnancy rate did not significantly differ whether the corpus luteum was on the right (1.62 +- 1.33ng/ml; 63.5 %) or left ovary (1.99 +- 0.61ng/ml; 85.0 %). Estradiol-17-beta levels were not significantly different between pregnant and nonpregnant recipients, but estradiol-17-beta levels (82.2 +- 13.5 VS. 72.3 +- 10.1pg/ml) were higher at below 1.0 ng/ml of progesterone. Total cholesterol levels on the day last PGF 2 alpha injection and day of transfer did not affect pregnancy rate. Calcium and inorganic phoshorus levels belonged to normal range in most of the recipients. These range did not affect pregnancy rate. In reviewing above results, plasma progesterone levels (1.0-4.0ng/ml) at the time of transfer are diagnostic value for screening recipients prior to transfer of frozen/thawed bovine embryos
Afficher plus [+] Moins [-]Effects of stage and quality of embryo, synchrony between donor and recipient and difficulty of transfer on pregnancy rate following non-surgical transfer of frozen-thawed bovine embryos
1989
Lee, E.S. | Jo, C.H. | Hwang, W.S. (Seoul National Univ., Suwon (Korea R.). Coll. of Veterinary Medicine)
This study was performed to investigate the effects of stage and quality of embryo, synchrony between donor and recipient and difficulty of transfer on pregnancy rate following non-surgical transfer of frozen-thawed bovine embryos. The overall pregnancy rate of this experiment was 63.4 % and that of heifers (73.1 %) was higher than that of cows (46.7 %). The pregnancy rates of recipients transferred with morulae, early blastocysts and blastocysts were 50.0 %, 64.7 % and 71.4 %, respectively. The pregnancy rate of recipients transferred with good embryos (67.9 %) was higher than that of recipients transferred with fair embryos (53.8 %). The pregnancy rates of embros transferred to left and right uterine horn were 63.2 % and 63.6 %, respectively. The pregnancy rate of recipients in estrous synchrony 0 (76.2 %) was higher than those of recipients in synchrony -1 (55.6 %) and +1 (44.4 %). The pregnancy rate of recipients transferred with 2 embryos (71.4 %) was higher than that of recipients transferred with 1 embryo (61.8 %). The pregnancy rate of embryos transferred to uterine tip (72.0 %) was higher than that of embryos transferred to uterine base (50.0 %). Ease of transfer was ranked to a scale of one to three on the basis of increasing difficulty. Transfers ranked as ease score 1 accounted for 77.8 % of pregnancies and had higher pregnancy rate than ease score 2 (66.7 %) or 3 (45.5 %). The pregnancy rate of recipients with excellent corpus luteum (CL) (70.0 %) was higher than those of recipients with good CL (61.1 %) or fair CL (61.5%). In reviewing above results, it was considered that the factors such as embryo stage, embryo quality, estrous synchrony, corpus luteum quality, tranfer site within uterus, recipient's parity and ease score affected the pregnancy rate after non-surgical transfer of frozen-thawed bovine embryos
Afficher plus [+] Moins [-]Serotypes of staphylococcus hyicus subsp hyicus isolated from pigs
1989
Kim, D.K. | Yeo, S.G. (Kyongsang National Univ., Chinju (Korea R.). Coll. of Veterinary Medicine)
Serotypes of S hyicus subsp hyicus strains isolated from healthy pigs and piglets with exudative epidermitis were identified with homogeneous factor sera. The serotypes of 489 strains were classified into 5 serotypes as A (16.8 %), C (20.4 %), D (9.4 %), E (7.2 %), F (29.2 %) and untypable (17.0 %). Serotype F was the most predominant strain regardless of health condition, body regions and age of the pigs
Afficher plus [+] Moins [-]Studies on body types by body growth and blood chemical values in the Jindo dog., 2; Body types by body growth in Jindo dogs
1989
Kim, W.K. | Lee, J.H. (Chonnam National Univ., Kwangju (Korea R.). Coll. of Veterinary Medicine) | Kim, J.S. (Chonnam Animal Health Laboratory, Kangjin (Korea R.). Kangjin Branch)
This investigation was conducted on 249 Jindo dogs aging from 2 to 12 months to determine body type and external appearance of the dogs. The withers height of male dogs growed rapidly during the period between 2 months and 7 months of age, and was 22.94cm and 49.77cm, respectively. Afterward the growth rate slowed down up to 12 months, 53.33cm. The growth rate of female was similar to male, and the withers height was 22.91cm, 46.81cm, 48.70cm at 2, 6 and 12 months of age. For male and female the body length was 27.21, 27.23cm at 2 months, 51.40cm, 51.62cm at 6 months, 58.33, 52.15cm at 12 months, respectively. Growth rate of the body length was very rapid from 2 to 6 months of age, but afterwards the growth rate was slow and somewhat retarded. For male and female, the withers height to body length ratio was 100 : 109.4 and 100 : 107.1 in 12 months old group. Cross over between the sexes in growth rate occurred between 5.3 to 6.5 months of age for wither height, between 6.0 to 7.2 months for body length, respectively. The average chest girths of male and female were 31.46, 30.46cm at 2 months, 54.92, 52.20cm at 7 months, 60.25, 57.90cm at 12 months, respectively. The growth rate of chest girth was rapid between 2 to 7 months of age and gradual between 7 to 12 months. The average skull lengths of male and female were 11.76, 11.32cm at 2 months, 21.83, 19.60cm at 12 months, respectively. The average head widths of male and female were 8.37, 7.94cm at 2 months, 15.47, 12.46cm at 12 months. Erected type of ear was completed from oblique type at 6 months in male and 7 months in female. On our detailed examinations, we concluded that Jindo dogs completed their growth at 6 to 7 months of age
Afficher plus [+] Moins [-]Alteration of neutrophil function associated with coccidiosis in cattle: influence of decoquinate and dexamethasone
1989
Roth, J.A. | Jarvinen, J.A. | Frank, D.E. | Fox, J.E.
Twenty Holstein steers subclinically infected with coccidia were allotted to 2 groups of 10 steers each. One group received a diet containing 0.5 mg of decoquinate/kg of body weight. After 25 days on the diet, there was no difference between the groups in lymphocyte blastogenic responsiveness mitogens; however, there were differences in neutrophil function. Lymphocytes from steers of the decoquinate-fed group had decreased random migration under agarose, enhanced cytochrome C reduction, and enhanced iodination activity. Other measures of neutrophil function evaluated (chemotactic index, Staphylococcus aureus ingestion, and antibody-dependent and-independent cell-mediated cytotoxicity) were not affected. After 30 days of decoquinate feeding, half of the cattle in each group received 5 daily IM injections of dexamethasone (0.04 mg/kg of body weight). The dexamethasone-treated steers from the group that did not have decoquinate in the diet developed clinical coccidiosis, whereas the decoquinate-treated steers remained clinically normal. Lymphocyte and neutrophil function were again evaluated for a 3-day period beginning 4 days after dexamethasone treatment was halted. Neutrophils from the steers that developed clinical coccidiosis after dexamethasone administration had significantly (P less than 0.05) inhibited random migration under agarose, cytochrome C reduction, and iodination activity, but significantly (P less than 0.01) enhanced S aureus ingestion. The feeding of decoquinate prevented the inhibition of neutrophil cytochrome C reduciton and lessened the inhibition of neutrophil iodination in the dexamethasone-treated group. Dexamethasone treatment was associated with an inhibition of lymphocyte blastogenic responsiveness to phytohemagglutinin in principals as well as controls.
Afficher plus [+] Moins [-]Whole blood platelet aggregation in dogs with liver disease
1989
Willis, S.E. | Jackson, M.L. | Meric, S.M. | Rousseaux, C.G.
Whole blood platelet aggregation was determined in response to collagen, arachidonic acid, and adenosine diphosphate in 20 dogs with liver disease and in 20 control dogs. Platelet aggregation in response to collagen and arachidonic acid was reduced in dogs with liver disease, compared with control dogs (P less than 0.05), whereas there was no significant difference in platelet response to adenosine diphosphate between the 2 groups of dogs. Adenosine diphosphate was found not to be a reliable aggregation agent for determination of whole blood platelets aggregation in dogs. Dogs whose platelet did not aggregate in response to collagen and/or arachidonic acid manifested bleeding tendencies that could be attributed to platelet dysfunction.
Afficher plus [+] Moins [-]Critical and controlled tests of activity of a macrocyclic lactone (compound F28249-alpha) against natural infections of internal parasites of equids
1989
Lyons, E.T. | Drudge, J.H. | Tolliver, S.C.
Thirteen critical tests (n = 11 horses and 2 ponies) and 4 controlled tests (n = 4 donkeys and 6 horses) were performed to evaluate the activity of the experimental macrocyclic lactone compound F28249-alpha against internal parasites of equids. In the critical tests, activity was determined mainly against the large parasites, but 1 critical test also included benzimidazole-resistant small strongyles. In the controlled tests, evaluation of drug activity included large parasites and stomach worms in all 4 tests and lungworms in 2 tests. The period between treatment and euthanasia was 6 to 9 days for the critical tests and 14, 17, or 52 days for the controlled tests. The compound was administered by stomach tube at dose rates of 1, 2, 3, 3.5, or 4 mg/kg of body weight. In the critical tests, removal at all 5 dose rates was 100% for Gasterophilus nasalis (2nd and 3rd instars), Parascaris equorum (mature), Strongylus vulgaris, and Strongulus edentatus from the gastrointestinal tract. For Gasterophilus intestinalis in the stomach, mean removals of 2nd instars were 88% at the rate of 2 mg/kg and 93% to 100% at rates greater than or equal to 3 mg/kg. For the 3rd instars, mean removals were 7% at 1 mg/kg, 77% at 2 mg/kg, 90% at 3 mg/kg, and 98% at 3.5 mg/kg. Discharge of G intestinalis in feces was typically a slow, prolonged process and probably higher removal values, especially at lower dose rates, would have attended a longer interval after treatment before necropsy examination. There was 100% removal of population B, benzimidazole-resistant small strongyles in the single critical test. Controlled tests at the 4 dose rates between 2 and 4 mg/kg resulted in variable activity against G intestinalis and Oxyuris equi, but efficacious removals were recorded for S vulgaris, S edentatus, Draschia megastoma Habronema muscae, Trichostrongylus axei, and Dictyocaulus arnfieldi. In critical and controlled tests, there was some indication of drug activity against parenteral stages of S edentatus and S vulgaris; activity was best in the control test equids euthanatized 52 days after treatment. There did not appear to be drug activity on eyeworms (Thelazia lacrymalis) or tapeworms (Anoplocephala spp). Toxicosis of transient nature was observed in 1 horse treated at 4 mg/kg.
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