| the effect of diet on the severity of losses from infectious bursal disease (gumboro) in a commercial broiler genetype. | a natural outbreak of infectious bursal disease occurred in an experimental broiler flock being reared on 3 starter diets having 18.8, 21.6 and 24.0 per cent protein. groups fed the highest protein starter exhibited significantly higher mortality and had larger numbers of stunted birds. | 1975 | 166366 |
| antibody response of genetically susceptible and resistant chickens to cell-free and attenuated jm-v leukosis strain and its influence on early type ii (marek's) leukosis infection. | experiments were carried out to: 1) determine the antibody response of chickens to cell-free and attenuated preparations of jmv leukosis strain, 2) determine the differences in antibody response to these antigens between susceptible (p-line) and resistant (n-line) chickens by means of serum neutralization and indirect fluorescent antibody tests, 3) investigate the influence of maternal (passive) antibody on early (day-old) jmv vaccination and 4) investigate the influence of maternal antibody in ... | 1975 | 166367 |
| pharmacology of neural modulation and transmission. | | 1975 | 166405 |
| effect of infectious bronchitis vaccination on the performance of live newcastle disease vaccine. | | 1975 | 166478 |
| expression of tumor-specific surface antigens on cells infected with temperature-sensitive mutants of avian sarcoma virus. | | 1975 | 166486 |
| alterations in surface proteins in chicken cells transformed by temperature-sensitive mutants of rous sarcoma virus. | | 1975 | 166490 |
| phagocytosis of lymphoblastoid cells and cell destruction of human malignant tumor cells. | on the basis of the previous study, on the cell interaction between malignant tumor cells and other cells, especially with lymphocytes, the present study was carried out by investigating cell to cell interaction of human malignant tumor cells and human lymphoblastoid cells such as t-cell (molt-4 cell) and b-cell (burkitt lymphoma cell). as a result it has been revealed that live lymphoblastoid cells were not adhered on the cell surface of the tumor cells, nor is it ingested by tumor cells, but i ... | 1975 | 166555 |
| the measurement of adenosine 3,5-monophosphate in bone. | | 1975 | 166572 |
| pyrimidine biosynthesis and its regulation in the estrogen-stimulated chick oviduct. | | 1975 | 166622 |
| progesterone receptors of chick oviduct: identification of 6s receptor dimers. | | 1975 | 166713 |
| the response of the immature fowl to multiple injections of adrenocorticotrophic hormone. | 1. treating chicks, from 1 d or 5 weeks of age with acth three times weekly for 3 weeks depresses growth and causes adrenal hypertrophy at dose rates of 30 iu/kg or more, and depletion of adrenal cholesterol (greater than 10 iu/kg). 2. treating chicks five times weekly at a dose rate of 30 iu/kg was as effective as a dose of 120 iu/kg three times weekly. 3. plasma glucose and ffa concentrations of chicks treated thrice weekly with 120 iu acth/kg for 3 weeks were within the normal range. 4. rhode ... | 1975 | 166732 |
| [phylogenetic study of hepatic microsomal glucokinases]. | | 1975 | 166791 |
| failure to obtain transfection with xc mitochondrial dna. | | 1975 | 166846 |
| effect of mycobacterium bovis and mycobacterium tuberculosis on the take and survival of chickens with transplanted mc-29 hepatoma. | | 1975 | 166869 |
| growth and cytopathology of mycoplasma synoviae in chicken embryo cell cultures. | mycoplasma synoviae was tested for its ability to grow and induce cytopathogenic changes in chicken embryo cell cultures. m. synoviae grew to high titers by day 5 in the presence of chick cells, but showed no growth in the tissue culture medium alone even though it was enriched with nicotinamide adenine dinucleotide and swine serum. infected chick cell cultures showed a progressive cytoplasmic degeneration on successive days of examination. early changes involved cytoplasmic granularity and mild ... | 1975 | 166927 |
| purification and regulatory properties of chicken heart prostaglandin e 9-ketoreductase. | prostaglandin e 9-ketoreductase was purified from chicken heart by ammonium sulfate fractionation, and deae-sephadex, hydroxylapatite and phosphocellulose chromatography. two peaks of activity were resolved during the phosphocellulose chromatographic step. both peaks were stimulated by a substance that was not bound to the phosphocellulose column. this stimulatory substance was destroyed by treatment with phosphodiesterase and 0.1 m naoh. it was heat-stable (100 degrees, 2 min), nondialyzable, a ... | 1975 | 166995 |
| effects of discrete nuclear u.v-microbeam irradiation on herpes virus and sv40 infection. | the requirement for a nucleolus in the expression of structural genes of nuclear viruses was examined by means of experiments in which the nucleolus or other parts of the nucleus was inactivated by a microbean of unltraviolet light. these experiments showed that the expression of such genes is not dependent on cucleolar function. this conclusion is discussed in the light of previous experiments in which similar inactiviation of nucleolus was shown to prevent the expression of cellular structural ... | 1975 | 167040 |
| use of the indirect fluorescent antibody method for detecting antibodies to infectious bronchitis virus in chickens serum. | | 1975 | 167061 |
| nature of the determinant responsible for the adhesion of lactobacilli to chicken crop epithelial cells. | using an in vitro method, some factors affecting the attachment of a strain of lactobacillus to chicken crop epithelial cells have been studied. time of contact beyond 10 min, ph value, age or growth temperature of the bacterial culture, or nature of the energy source in the growth medium had little or no effect on attachment. heating to 100 degrees c for 10 min, or treatment with edta or surface active compounds was also without effect. treatment with sodium periodate markedly decreased adhesio ... | 1975 | 167103 |
| transformation by a temperature sensitive mutant of rous sarcoma virus in the absence of serum. | cultures of chicken embryo fibroblasts infected with the temperature-sensitive transformation mutant of rous sarcoma virus, tsla24pr-a, were arrested between mitosis and s phase by exposure to serum-free medium at the non-permissive temperature (41degree c) for 2 days. on shifting to the permissive temperature (35degree c) the cells assumed a transformed morphology and increased uptake of [2minus 3h]-deoxy-glucose. there was a concomitant increase in acid insoluble [3h]-thymidine. this suggests ... | 1975 | 167110 |
| genetic control of resistance of chick embryo cultures to rsv (rav 50). | the genetic control of resistance of chick embryo cultures to rsv (rav 50) was studied in crosses between the highly inbred reaseheath lines, i, c and w and in the test-cross between wc(f1) and rprl line 7. embryo cultures resistant to rsv(rav2) were also resistant to rsv(rav 50). genetic analysis of the segregation results of resistance and susceptibility in the f2, back-crosses, and test-cross populations suggests that the tvb genes pleiotropically control the resistance of the embryo cultures ... | 1975 | 167112 |
| replication of reticuloendotheliosis viruses in cell culture: chronic infection. | after an initial acute infection with cell killing, chicken or duck embryo fibroblasts infected in culture with reticuloendotheliosis viruses set up a chronic infection with no cell killing or morphological transformation. essentially all of the chronically infected cells produced virus. the virus production was not sensitive to cytosine arabinoside or mitomycin c as was virus production in an acute infection. the chronically infected cells had a strong group-specific resistancto the c.p.e. of s ... | 1975 | 167114 |
| protein synthesis in sendai virus-infected cells. | the rate of protein synthesis in chicken embryo cells infected with sendai virus 18 to 20 h previously was about two times greater than in mock-infected controls. at this time of infection six stable virus-induced proteins, four major structural proteins (p, nh, np and m) and two non-structural proteins (28k and 61k), were identified by electrophoresis in sds-polyacrylamide gel of total cell extracts. the structural glycopeptide f was not detected in the infected cell extracts. pulse-chase exper ... | 1975 | 167115 |
| recombination between endogenous and exogenous rna tumor virus genes as analyzed by nucleic acid hybridization. | certain chicken cells that do not spontaneously release virus particles have been shown to produce a subgroup e avian rna tumor virus, rous-associated virus 60 (rav-60), after infection with viruses of other subgroups. the nucleic acids of rav-60 were analyzed for sequence homologies with the viral nucleic acids contained in the uninfected cell and with those of rav-2, the exogenous virus used for the preparation of this particular rav-60 isolate. in addition, these nucleic acids were compared w ... | 1975 | 167190 |
| comparative studies on the biological activities of cardiotoxin, melittin and prymnesin. | the actions of cardiotoxin (ctx), melittin and prymnesin were compared on dog erythrocytes, chicken biventer cervicis muscle, rabbit conjunctiva, acetylcholinesterase, succinate-cytochrome c reductase and turbidity of the rat liver mitochondrial suspension. 1. ctx and melittin were approximately equipotent in the various biological activities, while prymnesin was not. 2. the rate of direct ehmolysis induced by ctx was slow, while that induced by either melittin or prymnesin was fast. 3. phosphat ... | 1975 | 167293 |
| a study of cardiotoxic principles from the venom of bungarus fasciatus (schneider). | | 1975 | 167474 |
| newer knowledge in comparative virology--its contribution to human health research. | like other comparative sciences, and despite its recent beginning comparative virology has already contributed useful applications and observations to human health research. teachings derived from the study of marek's disease found application in that of burkitt's lymphoma, and may lead to a possible vaccine against the human disease. equally useful information came from the study of canine distemper in the development of a chorio-allantoic membrane attenuated measles vaccine, and in our knowled ... | 1975 | 167504 |
| letter: infectious bronchitis in vaccinated poultry. | | 1975 | 167505 |
| [distribution of the a and b serogroups of poultry leukosis viruses]. | | 1975 | 167508 |
| a phylogenetic study of the role of cyclic amp in lipid synthesis in vertebrates. | the effect of cyclic amp on the incorporation of acetate-2-14c into sterols and fatty acid in vitro in slices of liver and intestine was examined in various representatives of the vertebrate group. in no instance was an effect on lipid synthesis noted in intestine. cyclic amp exerted no significant effects on hepatic lipogenesis in lower vertebrates, including the nurse shark, catfish, toad, or iguana. however, the nucleotide strongly inhibited the incorporation of acetate-2-14c into fatty acid ... | 1975 | 167595 |
| comparison of the characteristics of avian reoviruses isolated from the digestive and respiratory tract, with viruses isolated from the synovia. | two-week-old gnotobiotic chicks were inoculated in the foot pad with viruses isolated from synovia and synovial membrane-wvu 1464-29h, wvu 1675, wvu 2937, wvu 2986, and wvu 71-212; from digestive tract-reoviruses 24, 25, and 59; or from respiratory tract-reovirus fahey-crawley (fc). all viruses induced swelling of the foot pad and inflammatory changes of synovial membrane. serum from virus-infected chicks had a common agar gel precipitin (agp) line. on the basis of the plaque-reduction test in p ... | 1975 | 167621 |
| comparative pathogenicity of avian encephalomyelitis viruses in chicken embryos. | multiplications of wild, various embryo-adapting and completely embryo-adapted avian encephalomyelitis (ae) viruses in chicken embryos were compared by the fluorescent-antibody technique (fat). with a wild ae virus, viral antigens were randomly seen in the central nervous system (cns), appearing least often in the cerebellum. other organs seldom became test positive, except for heart and kidney. even with 4 chicken brain-passaged viruses in the process of embryo adaptation, there was little augm ... | 1975 | 167624 |
| the enhancing effect of copper, nickel, and cobalt ions on plaque formation by semliki forest virus (sfv) in chicken embryo fibroblasts. | in cultured chicken embryo fibroblasts treated with copper-(copper cation 10-minus 3.5-10-minus 5 m), nickel and cobalt salts an enhancement of the plating efficiency of semliki forest virus could be observed. this augmented plaque formation was most probably due to a higher adsorption rate of virions to the cell surface under the influence of the transition metal ions. the plating efficiency of west nile virus in chicken-embryo fibroblasts and, to a lesser degree, of poliovius type 1 and 2 in k ... | 1975 | 167680 |
| studies of marek's disease herpesvirus and turkey herpesvirus specific common antigen which stimulates the production of neutralizing antibodies. | an agar-gel precipitation antigen prepared from the skin (feather-ag) of chicken infected with jm strain of marek's disease herpesvirus (mdhv) and cell extracts of cultures infected with either type 2 plaque producing agent (ppa) of mdhv or turkey herpesvirus (hvt) (type 2-ag, hvt-ag) had 1 precipitation line in common. hyperimmune sera to the common antigen (common-ag) neutralized to a greater extent by homologous antiserum. absorption of hvt antiserum or hyperimmune serum to type 2 ppa with co ... | 1975 | 167687 |
| role of glycerol 3-phosphate dehydrogenase in glyceride metabolism. effect of diet on enzyme activities in chicken liver. | 1. the metabolic role of hepatic nad-linked glycerol 3-phosphate dehydrogenase (ec 1.1.1.8) was investigated vis-a-vis glyceride synthesis, glyceride degradation and the maintainence of the nad redox state. 2. five-week-old chickens were placed on five dietary regimes: a control group, a group on an increased-carbohydrate-lowered-fat diet, a group on a high-fat-lowered-carbohydrate diet, a starved group and a starved-refed group. in each group the specific activity (mumol/min per g wet wt. of ti ... | 1975 | 167714 |
| studies on vitamin d and its analogs. viii. 3-deoxy-1alpha, 25-dihydroxyvitamin d3, a potent new analog of 1alpha, 25-(oh) 2-d3. | | 1975 | 167766 |
| the amino acid sequence of chick skin collagen alpha1-cb7. | the amino acid sequence of chick skin collagen alpha1-cb7, the 268 cnbr peptide from the helical portion of the alpha1 chain, has been determined by automatic and manual degradation of tryptic and chymotryptic peptides, and of the cooh-terminal fragment produced by cleavage with animal collagenase. the resulting sequence shows 94% identity with that of the corresponding peptide from calf skin collage (fietzek, p. p., rexrodt, f. w., hopper, k. e., and kühn, k. (1973), eur. j. biochem. 38, 396). ... | 1975 | 167810 |
| proceedings: cyclic amp in developing chick brain: changes with ischaemia and catecholamine administration. | | 1975 | 167897 |
| fibrin overlay methods for the detection of single transformed cells and colonies of transformed cells. | fibrin overlay methods are described which can detect the plasminogen activator produced by single transformed cells or small colonies of transformed cells. these methods were applied to malignant cells derived from humans, mice, hamsters, rats, and chicks. the lysis observed was plasminogen dependent. transformation of chicken cells by rous sarcoma virus was detected 4 days after infection. the number of lysis zones produced was proportional to the virus inoculum and was identical to the number ... | 1975 | 167984 |
| [the effect of alloxan on the multiplication of different types of normal or cancerous cells, and on the transformation of chick embryo fibroblasts by rous virus in vitro]. | the action of alloxan was studied in vitro, on different categories of normal or cancerous cells. at concentrations of 250 and 350 gamma/ml, alloxan does not significantly inhibit the growth of normal cells, whereas it does inhibit the growth of cancerous cells. furthermore, alloxan inhibits infection and transformation of chicken-embryo fibroblasts infected by the rous virus. | 1975 | 167998 |
| reactivity of serum from rous-sarcoma-bearing chickens with autochthonous and with allogeneic tumor cells: preferential autochthonous recognition. | complement-medicated cytotoxicity and indirect immunofluorescence assays showed that sera from random-bred chickens bearing rous sarcoma (rs) tumors are usually more reactive in vitro against rs cells of autochthonous than of allogeneic origin. absorption of such sera with autochthonous, but not with allogeneic, rs cells abrogated the fluorescence staining capacity. sera from tumor-bearing birds did not stain normal chicken embryo cells (cec), but reacted with a higher proportion of cec transfor ... | 1975 | 168159 |
| depression of in vitro responsiveness to phytohemagglutinin in spleen cells cultured from chickens with marek's disease. | cultures of dispersed spleen cells, prepared from mdv-infected chickens with md visceral lymphomas, showed marked depression of responsiveness to the t cell mitogen pha, as measured by 3h-tdr incorporation in cells in vitro. when data are expressed quantitatively in terms of cpm/10(5) viable cells, the functional depletion of pha-responsive cells appear to result from lower levels of 3h-tdr incorporation in the pha-stimulated spleen cultures from chickens with acute md symptoms, as compared to s ... | 1975 | 168267 |
| proceedings: metabolism and specific binding of parathyroid hormone in chick kidney plasma membranes. | | 1975 | 168291 |
| aspects of the adrenal function in the domestic fowl. | chromatographic purification of extracts of hen peripheral plasma on florisil columns before measurement by spectrofluorometry showed a basal level for corticosterone of 1-3 mug/100 ml, which is much lower than concentrations previously reported using acid fluorescence. neither handling, restraint nor repeated bleeding affected the concentration of this hormone or of glucose. adrenal function tests with two preparations of synthetic corticotrophin showed that they caused a rapid rise in blood co ... | 1975 | 168295 |
| poxvirus infection in the white-backed magpie (gymnorhina hypoleuca) and pox-like conditions in other birds in australia. | lesions, grossly and histologically typical of pox infection, occurred in a white-backed magpie from melbourne, australia. electron microscopic examination revealed typical poxvirus particles in lesion material. the disease was experimentally transmitted to other magpies, but chickens, turkeys, pigeons, and canaries were refractory to experimental infection with magpie poxvirus. the epidemiology of magpie pox and the probable occurrence of pox-like disease in other native australian birds are di ... | 1975 | 168411 |
| methods for assessing hormone effects on calcium fluxes in vitro. | | 1975 | 168475 |
| effect of selected environmental treatments on the incidence of gross marek's disease lesions in chickens. | the effects of selected environmental treatments on the incidence of gross marek's disease (md) lesions in chickens contact exposed to md virus were examined. treatments were high levels of airborne decomposition products from chicken litter in the rearing environment, disinfectants applied to chickens and their environments, and formaldehyde fumigation of eggs and newly hatched chicks. there were no significant differences in the incidence of gross md lesions when treated and untreated groups w ... | 1975 | 168563 |
| serological responses of broiler-type chickens, with and without newcastle disease and infectious bronchitis vaccine, to experimental infection with mycoplasma synoviae by foot pad, air sac and aerosol. | serum plate (sp) and tube agglutination (ta) reactions and geometric mean mycoplasma synoviae (ms.) hemagglutination-inhibition (hi) titers were determined on chickens infected at 21 days of age with ms. by foot pad, air sac and aerosol. one-half had been given newcastle disease (nd) and infectious bronchitis (ib) vaccine in the water at 20 days of age, and the other half had not been vaccinated with nd and ib vaccine. blood was taken at 3, 4, 6 and 8 weeks after ms. infection. geometric mean hi ... | 1975 | 168564 |
| molecular sizes of egg yolk very low density lipoproteins fractionated by ultracentrifugation. | egg yolk very low density lipoproteins isolated from normal eggs were separated into six fractions by preparative ultracentrifugation. the sizes of the molecules in three of the fractions were estimated by gel chromatography and by electron microscopy of the lipoproteins using a negative staining technique. the three fractions had average diameters of 39 nm., 32 n., and 25 nm. and average molecular weights of 17 x 10(6), 10 x 10(6), and 5 x 10(6). there was considerable overlap of size of molecu ... | 1975 | 168566 |
| [serum and liver lipase activity in chickens during the 1st month of life]. | method according to dirstine (1968) was employed to study the activities of serum and liver lipase in white leghorn cockerels during early post-incubation ontogenesis; as to serum lipase, two embryo intervals were also studied (the 13th and 20th day of incubation). from the average value of 4.4 ummol (13th day), serum lipase activity increased to the average value of 7.5 ummol (20th day). the first day after hatching the average value was 3.5 ummol which remained almost unchanged until the 9th d ... | 1975 | 168679 |
| trials with marek's disease vaccines prepared from a turkey herpes virus and an attenuated marek's disease virus. | in field trials involving over 224,000 fowls in 11 different commercial flocks, three vaccines were used, namely a freeze-dried vaccine prepared from a turkey herpes virus, a cell-associated virus vaccine prepared from the same isolate and a cell-associated vaccine prepared from a strain of marek's disease virus isolated from a fowl. the mortality from marek's disease was reduced by 80 per cent to 95 per cent in birds vaccinated with the freeze-dried vaccine. cell associated vaccines gave slight ... | 1975 | 168681 |
| biochemical characterization of tumor-specific cell surface antigens on avian oncornavirus transformed cells. | | 1975 | 168686 |
| [one aspect of evolutionary pharmacology. oligomerization of cholinoreceptors during development of the animal kingdom]. | | 1975 | 168702 |
| [participation of 3',5'-amp in the primary mechanisms of exteroreceptive processes]. | | 1975 | 168703 |
| primary lymphoreticuloses of the nervous system in animals. | lymphoreticular proliferative disorders occur in most species of animals including submammalian vertebrates but only occasionally affect the nervous system. primary lymphoreticular disorders of the nervous system have been recognized in chickens as a herpesvirus-induced avian neurolymphomatosis and in mammals, patricularly in the dog, as reticulum cell sarcomas originating from perivascular mesenchymal precursor cells. criteria have been discussed to distinguish neoplastic from inflammatory lymp ... | 1975 | 168723 |
| influence of vaccination with avirulent herpesvirus on subsequent infection of chickens with virulent marek's disease herpesvirus. | vaccination of chickens with turkey herpesvirus (hvt) or attenuated marek's disease herpesvirus (amdhv) blocked infection with virulent mdhv (vmdhv) for approximately 5 weeks after contact exposure. however, there was no apparent blockage of infection when challenge virus was administered intraabdominally (ia). evidence for infection with vmdhv was based on viral isolation by in vivo assay or by detecting precipitins to "a" antigen associated with virulent virus. the hvt stimulated production of ... | 1975 | 168799 |
| experimental transmission of japanese encephalitis virus by culex tritaeniorhynchus and c. fuscocephalus. | experimental transmission of japanese encephalitis virus from swine to baby chicks was accomplished using culex tritaeniorhynchus and culex fuscocephalus, two of three mosquito species in taiwan from which the virus has been recovered in nature. whereas neither species had become infective by the twelfth day, one of ten c. fuscocephalus and 11 of 51 c. tritaeniorhynchus were infective by the seventeenth day of extrinsic incubation as verified by viraemia in chicks fed upon by potentially infecti ... | 1975 | 168819 |
| avian leukosis-historical perspectives. | | 1975 | 168848 |
| two levels of genetic resistance to lymphoid leukosis. | two levels of genetic resistance to lymphoid leukosis are recognized: 1) cellular resistance to virus infection; and 2) resistance to tumor development in leukosis-virus-infected birds. resistance to infection is simply inherited but is very specific for the subgroup of virus. inheritance of resistance to tumor development is more complex but appears to be less subgroup-specific. a breeder may wish to select for resistance to infection of virus eradication is the goal. if his goal is the reducti ... | 1975 | 168849 |
| phenotypic mixing test to detect and assay avian leukosis viruses. | a phenotypic mixing (pm) test for detecting and assaying avian leukosis viruses (alv) of the a, b, c, and d subgroups is described. an alv and rous sarcoma virus rsv-0) are phenotypically mixed by co-cultivating on c/o (cells susceptible to all subgroups of alv) cells for a certain period. then the rsv with the new virus property is assayed on c/e cells (cells resistant to infection with subgroup e leukosis/sarcoma viruses). the test is relatively simple and rapid, and its results are unequivoca ... | 1975 | 168850 |
| two new isolants of infectious bronchitis virus with polyvalent immunogenicity. | the immunizing capacity of two new field isolants of avian infectious bronchitis virus (ibv) was tested in vivo. chickens vaccinated with either isolant resisted challenge with 6 serotypes of ibv, including some of the types most commonly isolated from chickens. the two new isolants, identified herein as california "g" and california "s," appear to be immunologically different from each other and from the other 6 types tested. the polyvalent immunogenicity of both g and s is noteworthy, and pote ... | 1975 | 168851 |
| identification of infectious bronchitis virus by interference with the b-1 isolant of newcastle disease virus. waxing and waning of interference. | the massachusetts and the connecticut types of infectious bronchitis virus (ibv) were identified by interference in embryonating chicken eggs (ece) with the production of hemagglutinin by the b-1 isolant of newcastle disease virus (ndv). this interference test appears to be specific because the above interference was eliminated by adding type-specific anti-ibv serum to the ibv-ndv system; however, interference was not detectable when fowlpox virus (fpv) and infectious laryngotracheitis virus (lt ... | 1975 | 168852 |
| immunity levels against avian encephalomyelitis in vaccinated poultry breeder flocks in maine. | four commercial poultry breeder flocks that were vaccinated under field conditions against avian encephalomyelitis (ae) with commercial live or inactivated vaccine were monitored periodically by virus-neutralization testing of blood serum samples and by challenge of their progeny eggs and chicks. the history of the flocks and results of the tests indicate that field exposure might occur during the laying period, thereby boosting immunity titers without causing clinical ae in the progeny chicks. ... | 1975 | 168853 |
| the addition of fowlpox and pigeon pox vaccine to marek's vaccine for broilers. | laboratory and field studies indicated that a cell-culture fowlpox vaccine was effective and safe when administered subcutaneously to day-old broiler chicks in combination with cell-associated marek's vaccine without compromising the latter. pox vaccines of chick embryo origin evaluated similarly provided excellent protection, although they caused local musculature swelling when injected into muscle rather than under the skin. no muscle swelling followed improper vaccination with the cell-cultur ... | 1975 | 168854 |
| a genetic analysis of adult mortality in leghorn by heavy-breed reciprocal crosses. | 1. genetic mechanisms of resistance to disease in 1930 pullets and 296 cockerels were investigated by using a leghorn line (g), a heavy-breed line (h), and their reciprocal crosses g x h and h x g plus two synthetic lines, gnh and hng which were segregating for line-intact z chromosomes. 2. the most frequent cause of death was leukosis. 3. gmale x hfemale pullets had a significantly higher adult mortality (40-9%) than the reciprocal cross (27-3%). 4. a direct effect of the z sex chromosome on th ... | 1975 | 168945 |
| dietary aureomycin and the response of the fowl to stressors. | 1. conventional or gnotobiotic chicks, when injected from 1 d to 3 weeks of age with adrenocorticotrophic hormone (120iu/kg, three times weekly), showed a depressed growth rate, adrenal hypertrophy and depletion of cholesterol form the adrenal glands. 2. feeding a diet supplemented with aureomycin (10 mg/kg) did not have any consistent ameliorating effect on the response of the stressed bird as judged by the above parameters. 3. it was found that treating germfree chicks with five daily injectio ... | 1975 | 168946 |
| studies on characterization of the integration sites of avian rna tumor virus-specific dna. | a sequential hybridization procedure is described which allows the integration sites of viral-specific dna to be characterized according to their reassociation kinetics. in addition, this approach enables us to estimate the size of the integrated viral dna. endogenous virus sequences in normal cells appear to be associated with cell sequences reiterated 1200 times, and each integration unit is approximately equal to one 35s rna subunit. in amv-infected cells, the additional amv-specific dna sequ ... | 1975 | 169002 |
| infectious viral dna in rous sarcoma virus-transformed nonproducer and producer animal cells. | nonproducer and producer rsv-transformed cells and producer nontransforming virus-infected cells harbor viral dna specifying the respective avian tumor virus. in nonproducer rous sarcoma cells, the residing viral dna is linear, double-stranded and covalently linked to the chromosomal dna. both double-stranded and single-stranded forms of rsv dna transfect chicken cells. the progeny virus is indistinguishable from the dna parent with respect to the morphological, biological and antigenic properti ... | 1975 | 169003 |
| infectious dna from cells infected with rous sarcoma virus, reticuloendotheliosis virus or rous-associated virus-o. | we have described an efficient and quantitative assay for infectious dna of the avian ribodeoxyviruses and have applied this method to study the possible existence of infectious viral dnas in uninfected cells. infectious dna from cells infected with rsv or rev consisted of a single unit of dna with a specific infectivity of 10(-5)-10(-6). the minimum molecular weight of rsv dna required for infection of chicken cells was about 6 million, while the minimum molecular weight of infectious rev dna w ... | 1975 | 169004 |
| amv rna transcription in cell-free systems and properties of in vitro chromatin-directed rna synthesis. | in this report we have presented evidence that viral sequences in the genome of amv-infected myeloblasts can be transcribed in vitro. the rna products synthesized in either nuclei isolated from these cells or by eukaryotic rna polymerase b from the isolated chromatin contained approximately 1% virus-specific sequences. this result, which is in agreement with the fraction of viral rna in infected cells (garapin et al. 1971), is higher than expected from a random transcription of the genome, and t ... | 1975 | 169005 |
| synthesis of avian rna tumor virus structural proteins. | | 1975 | 169008 |
| problems of rsv rescue from virogenic mammalian cells. | | 1975 | 169009 |
| control expression of tumor virus genes in uninfected chicken cells. | | 1975 | 169015 |
| studies of the interrelationship of chicken leukosis virus and host cell genomes by rna-dna hybridzation. | | 1975 | 169042 |
| structure and properties of an rna primer for initiation of rous sarcoma virus dna synthesis in vitro. | | 1975 | 169047 |
| [gas edema in broilers]. | | 1975 | 169118 |
| 1,25-dihydroxycholecalciferol-like activity in solanum malacoxylon: purification and partial characterization. | | 1975 | 169151 |
| effect of denaturation on the susceptibility of proteins to enzymic phosphorylation. | heat-denatured chicken egg white lysozyme and the reduced carboxymethylated maleylated derivative of this protein were found to serve as substrates for rabbit skeletal muscle cyclic amp-dependent protein kinase. the native form of the protein was not a substrate. two phosphoryl groups per mole of lysozyme were incorporated in the reaction. it was determined that the phosphoryl moieties were bound to serine 24 and serine 50 in the modified protein. serine 24 was phosphorylated approximately 3 tim ... | 1975 | 169238 |
| lack of feedback regulation of cyclic 3':5'-amp accumulation by free fatty acids in chicken fat cells. | fat cells isolated from the mesenteric adipose tissue of chickens (pullets) responded to glucagon with an increase in lipolysis and a sustained rise in cyclic adenosine 3':5'-monophosphate (cyclic amp) over a 30-min incubation. the prolonged accumulation of cyclic amp due to glucagon in chicken fat cells was primarily intracellular. in addition, there was little increase in cyclic amp accumulation due to theophylline alone or potentiation of the increase due to glucagon. these data indicate that ... | 1975 | 169253 |
| interaction of a chick skin collagen fragment (alpha1-cb5) with human platelets. biochemical studies during the aggregation and release reaction. | the denatured alpha1(i) chain and the cyanogen bromide peptide, alpha1(i)-cb5, of chick skin collagen cause the release of serotonin and leakage of lactic dehydrogenase from human platelets in a manner similar to the release reaction mediated by adenosine diphosphate and native collagen. these peptides also cause a decrease in the level of adenosine 3':5'-monophosphate (camp) in platelets. adenylate cyclase activity of platelets is partially inhibited by these peptides as well as by native colla ... | 1975 | 169261 |
| use of the unlabeled antibody immunohistochemical technique for the detection of human antibody. | two methods have been developed which permit use of the unlabeled antibody immunohistochemical technique for detection of human antibody, without the need for immunization of humans with peroxidase. human antibody to herpes simplex virus (hsv) reacted with human cell cultures infected with hsv was the experimental system. in the first method an attempt was made to employ rabbit peroxidase-antiperoxidase (pap) soluble complexes in connectin with human antibody. this was done by sequential additio ... | 1975 | 169304 |
| genetic susceptibility of chicken times quail hybrid embryos to avian rna tumour viruses. | an attempt was made to hybridize the chicken (gallus domesticus) male with japanese quail (coturnix coturnix japonica) female in order to study the genetic susceptibility of hybrid embryos to avian rna tumour viruses of subgroups, a, b, d and e. in the hybrids the results supported the prevailing concept that susceptibility is dominant over resistance regardless of the dominant trait contributed by either parent. it was also observed that the ie gene of the chicken was unable to suppress the 'qu ... | 1975 | 169318 |
| oncogenesis by marek's disease herpesvirus in chickens lacking expression of endogenous (gs, chick helper factor, rous-associated virus-o) and exogenous avian rna tumor viruses. | chickens free of exogenous avian leukosis virus (alv) infection, replicating endogenous alv (rous-associated virus-o), gs antigen, and chick helper factor were fully susceptible to induction of marek's disease (md) by alv-free md viruses. dual infection with rous-associated virus-2 and md virus did not significantly alter the character of the md lesions. thus exogenous alv infection was not requisite for md virus-induced oncogenesis. although participation of endogenous rna tumor virus genes in ... | 1975 | 169364 |
| low oncogenic potential of avian endogenous rna tumor virus infection or expression. | of chickens either spontaneously producing or exogenously infected in ovo with rous-associated virus, type o (rav-o), an endogenous virus of the chicken, only 1 died with lymphoid leukosis (ll), the most common neoplasm associated with the leukosis-sarcoma virus group. because the chickens were not kept in strict isolation, it could not be assumed that the one ll was induced by rav-o. in contrast, rav-1-infected chickens from the same lines had a high incidence of ll and other neoplasms. over 80 ... | 1975 | 169382 |
| mitochondrial and herpesvirus-specific deoxypyrimidine kinases. | to characterize and compare the thymidine (tdr) and deoxycytidine (cdr) kinase isozymes of uninfected and herpesvirus-infected cells: (i) the subcellular distribution of the isozymes has been studied; (ii) a specific assay for cdr kinase has been devised; (iii) the tdr kinase isozymes have been partially purified; and (iv) the purified enzymes have been analyzed by disc polyacrylamide gel electrophoresis, isoelectric focusing, and glycerol gradient centrifugation and by substrate competition and ... | 1975 | 169387 |
| physiology of the natural polyamines putrescine, spermidine and spermine. | the biochemistry and biological function of the naturally occurring polyamines, putrescine, spermidine, and spermine, have been reviewed with special reference to animal organisms. these compounds are universally distributed in all living material. their biosynthesis from ornithine and methionine is accurately controlled and may fluctuate according to the metabolic needs of the cell. polyamines strongly and specifically interact with nucleic acids in vitro. it appears that under physiological co ... | 1975 | 169440 |
| polypeptides isolated from ribosome-like structures occluded in avian myeloblastosis virus (amv). | the protein composititon of ribosome-like particles isolated from amv was determined by acrylamide gel electrophoresis and by immunological methods. it was established that the protein spectrum of ribosome-like particles differed significantly form the total protein spectrum of amv. the most characteristic protein components of ribosome-like particles had a molecular weight in the range of 70 000--110 000. apart from these proteins, the viral ribosomal particles contained a small amount of prot ... | 1975 | 169489 |
| reduction of clostridium perfringens by feed additive antibiotics in the ceca of chickens infected with eimeria tenella. | two experiments were performed ot investigate the effect of feed additive antibiotics on clostridium perfringens and enterobacteriaceae in the ceca of chickens infected with eimeria tenella. in the first experiment, chickens were continuously fed rations containing thiopeptin, 2 mg./kg.; bacitracin, 20 mg./kg.; penicillin, 12 mg./kg.; or chlortetracycline, 22 mg./kg. one day after antibiotic feed was given, each bird received an oral inoculation of 30,000 e. tenella oocysts. the growth of c. per ... | 1975 | 169521 |
| [peroral immunization against pox. 5. effectiveness of drinking water vaccination against fowl pox]. | | 1975 | 169653 |
| bluetongue: the disease in cattle. | most researchers in south africa found that although bt virus could be isolated from apparently healthy cattle and from inoculated cattle the virus did not produce overt clinical disease in cattle. however, when epizootics were reported outside africa, clinical signs were observed in cattle in israel, palestine, syria, portugal, and spain. most natural bt infections in cattle in the united states do not result in overt clinical signs. however, in certain infected herds, approximately 5% of the c ... | 1975 | 169786 |
| the comparative sensitivity of sheep and chicken embryos to bluetongue virus and observations on viraemia in experimentally infected sheep. | the virus titre in sheep blood samples received from bt-suspected cases in the field was assayed in sheep and in chicken embryos. these infected blood samples represented 3 different bt virus types: 4, 10 and 16. three identical experiments were performed, one with each of the 3 different virus types. ten-fold dilutions of the infected blood samples were prepared and 1 ml of each blood dilution was inoculated iv into series of 10 to 12-month old susceptible sheep; at the same time 0.1 ml of each ... | 1975 | 169790 |
| epizootiology of bluetongue: the situation in the united states of america. | bluetongue was first reported in the united states in 1948 in sheep in texas. the virus has now been isolated from sheep in 19 states. when the disease first occurs in a flock, the morbidity may reach 50 to 75% and mortality 20 to 50%. in subsequent years, the morbidity may be only 1 to 2% with very few deaths. difference in breed susceptibility has not been observed. natural bluetongue infection has not been observed in angora or dairy goats. bluetongue virus was first isolated from cattle, in ... | 1975 | 169793 |
| eradication of subgroups a and b lymphoid leukosis virus from commercial poultry breeding flocks. | a specific-pathogen-free pedigreed breeding population of white leghorns was determined to be free of lymphoid leukosis subgroups (ll-a and ll-b) on the basis of the standard resistance-inducing factor (rif) test of sera of individual birds. the fourth pedigreed generation (g-4) was the first to test free of viruses of both sub-groups. in three subsequent pedigreed generations (g-5 through g-7) no viremic birds were found. the rif test of sera was also used to detect carriers infected with ll-a ... | 1975 | 169799 |
| morphological changes of chicken tracheas and tracheal organ cultures infected with avian infectious bronchitis virus studied in scanning electron microscope. | chicken tracheas infected in vitro in organ culture and in vivo with avian infectious bronchitis virus (ibv) were studied by scanning electron microscopy. in in vitro infection in organ culture the columnar epithelial cells lining the tracheal ring lost their cilia and rounded up in 48 hr. there were numerous elevations and holes on the infected cell surface. subsequently the cells sloughed off. in in vivo infection the tracheal epithelial cells lost their cilia in 4 days. these cells without ci ... | 1975 | 169800 |
| rous sarcoma regression in chickens resistant or susceptible to marek's disease. | in 4 experiments, strains of chickens relatively susceptible (s-strain, p-line) or resistant (n-line, pdrc) to marek's disease (md) were challenged with rous sarcoma virus (rsv) at 6-8 weeks old. rsv tumors occurred in 94-100% of the birds in each strain, but the number with tumors that regressed during the 40-46-day experiment varied from 7% (s-strain) to 91% (pdrc). the n-line and p-line birds, derived from a random-bred flock with selection only for susceptibility or resistance to md, regress ... | 1975 | 169801 |
| avian encephalomyelitis virus in chicken pancreatic cell cultures. | monolayer cell cultures consisting of epithelioid cells were made from pancreatic tissue of 10-to-13-day-old chicks. the maximum virus titer of the cell-culture fluid was obtained 8 days after inoculation with an embryo-adapted avian encephalomyelitis virus (aev). virus titers also increased in cell cultures inoculated with a chick-pancreas-passed aev or a field isolant. cell cultures inoculated with 3 strains of aev maintained virus titers of 10(2.9)-10(3.7) 50% embryo-infective doses/ml for 15 ... | 1975 | 169803 |
| serotyping of avian infectious bronchitis viruses by the virus-neutralization test. | the antigenic relationships of 12 strains of infectious bronchitis virus (ibv) were evaluated by a virus-neutralization procedure similar to that used in typing human rhinoviruses. such a procedure consists of reciprocal neutralization tests performed by reacting 32-320 eid50 or plaque-forming units of virus with 20 antibody units of antiserum. eight serologic groups were identified by chicken embryo assay, and 4 by plaque-reduction (90%). in general, serologic groupings were not distinct but re ... | 1975 | 169804 |
| quantitative and qualitative differences in dna complementary to avian myeloblastosis virus between normal and leukemic chicken cells. | hybridization of avian myeloblastosis virus (amv) rna with dna immobilized on filters or in liquid with a vast dna excess was used to measure the viral specific dna sequences in chicken cells. newly synthesized viral dna (v-dna) appears within an hour after infection of chicken embryo fibroblasts (cef) with avian oncornaviruses. a fraction of newly synthesized v-dna becomes integrated into the cellular genome and the remainder gradually disappears. a covalent linkage between v-dna and cellular d ... | 1975 | 169823 |
| continuous cell culture from lymphoma of marek's disease. | | 1975 | 169828 |
| production of species-unspecific antiviral inhibitors in cell-cultures and in chicken embryos under the influence of pyrazolon derivatives. | | 1975 | 169855 |