Humoral antibody response to cattle to formalinized Staphylococcus aureus vaccine.

Five cows were inoculated intradermally with formalinized Staphylococcus aureus suspension in Freund's complete adjunvant and the development of the humoral antibody response was followed as judged by the agglutination titer of sera, at various intervals post inoculation. Highest titers were observed at 78-87 days post inoculation. Agglutinating activity was found in IgM and IgG fractions (IgG1 and IgG2) of both serum and colostrum. The agglutinating activity of colostrum was significantly higher at 12 than at 24 and 36 h, post partum. However, no such activity was detected in either normal cow serum or colostrum against S. aureus.     

Indirect microhemagglutination test for varicella--zoster antibody determination.

An indirect microhemagglutination assay (IHA) was devised because of a need to provide an alternative test to complement fixation (CF) for varicella-zoster (V-Z) antibody determination. Human erythrocytes were sequentially treated with 2% glutaraldehyde, 0.04% tannic acid, and 2% pyruvic aldehyde then exposed to sonicated V-Z infected cells. This same tanning procedure was suitable for herpes simplex and Epstein-Barr virus antigen attachment but unsatisfactory for several non-herpes-group viruses. V-Z antibody titres determined by IHA were generally 2 to 6 times higher than CF titres. Cross-reaction with herpes simplex antibody was minimal.     

Experimental Sarcocystis hominis infection in cattle: lesions and ultrastructure of sarcocysts

Five calves inoculated orally with 10(5)-10(6) sporocysts of Sarcocystis hominis from human feces were necropsied 10, 18, 24, 111, and 222 days postinoculation (DPI). Calves became febrile (greater than 40-41 C) between 10 and 24 DPI and developed mild anemia (packed cell volumes were reduced by 40% of initial values) between 29 and 57 DPI but otherwise remained clinically normal. Focal hepatitis, mesenteric lymphadenitis, and myocarditis were seen in calves at 10, 18, and 24 DPI. No stages of the parasite were found at any of these times except for a few merozoites in macrophages associated with myocardial lesions in the calf necropsied 24 DPI. Mature sarcocysts at 111 and 222 DPI were up to 950 microm long and their walls were up to 6 microm thick. They were found only in skeletal muscles. One immature sarcocyst was seen in the myocardium of the calf at 222 DPI.     

Lack of Sarcocystis neurona antibody response in Virginia opossums (Didelphis virginiana) fed Sarcocystis neurona-infected muscle tissue

Serum was collected from laboratory-reared Virginia opossums (Didelphis virginiana) to determine whether experimentally infected opossums shedding Sarcocystis neurona sporocysts develop serum antibodies to S. neurona merozoite antigens. Three opossums were fed muscles from nine-banded armadillos (Dasypus novemcinctus), and 5 were fed muscles from striped skunks (Mephitis mephitis). Serum was also collected from 26 automobile-killed opossums to determine whether antibodies to S. neurona were present in these opossums. Serum was analyzed using the S. neurona direct agglutination test (SAT). The SAT was modified for use with a filter paper collection system. Antibodies to S. neurona were not detected in any of the serum samples from opossums, indicating that infection in the opossum is localized in the small intestine. Antibodies to S. neurona were detected in filter-paper-processed serum samples from 2 armadillos naturally infected with S. neurona.     

Color test for the measurement of antibody to T-strain mycoplasmas

Purcell, Robert H. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.), D. Taylor-Robinson, D. Wong, and R. M. Chanock. Color test for the measurement of antibody to T-strain mycoplasmas. J. Bacteriol. 92:6-12. 1966.-A metabolic inhibition technique for the measurement of antibody to T-strain mycoplasmas was developed, based upon the ability of T-strain mycoplasmas to metabolize urea with the concomitant production of ammonia, and the ability of specific antiserum to inhibit this ammonia production. Phenol red added to the medium served as an indicator of pH change resulting from ammonia production. Specific antiserum to T-strain mycoplasma T-960 was prepared. The T-strain organism was shown to be serologically distinct from the recognized large-colony mycoplasmas. Antibody to mycoplasma strain T-960 in human sera was demonstrated with the metabolic inhibition technique.     

Antibody estimation by indirect complement fixation test for foot-and-mouth disease in cattle.

Antibody against foot-and-mouth disease (FMD) virus was measured by the indirect complement fixation (ICF) test. For this test serum samples were collected from cattle experimentally infected with FMD virus of O, A and Asia 1 types, as well as cattle infected in the field. Two types of antigen were used. One was antigen derived from infected lingual epithelial culture prepared by Frenkel's method with each type of the virus. The other was antigen derived from the lingual epithelium of cattle infected by virus inoculation. ICF antibody began to be dectected about 4 5 days after inoculation. It reached a maximum titer 10 14 days after inoculation, remaining at this titer for about a week or two, and then decreased gradually. It was, however, detectable even 63 days after inoculation. The rise and fall of ICF antibody was parallel with that of neutralizing antibody, although that antibody was always lower in titer than this. ICF antibody was detected type-specifically from cattle infected experimentally and naturally. These results indicated that the ICF test was available for the routine serological diagnosis and epizootiological investigation and research.     

Mumps prophylaxis in the light of a new test for antibody.

A radial haemolysis test was used to investigate immunity to mumps. Antibody was found in 92 (42%) out of 220 children aged up to 5 years, 124 (78%) out of 159 children aged 6--10 years, 192 (86%) out of 222 children aged 11 years, 138 (92%) out of 150 children aged 15 years, and 280 (95%) out of 296 women attending an antenatal clinic. A group of 307 cadets aged 16--18 years were also tested and interviewed: 133 (95%) out of 140 who said that they had had mumps and 108 (87%) out of 124 who said that they had not had mumps were found to have antibody. The results suggest that tests for immunity to mumps by radial haemolysis would permit more rational use of mumps-specific immunoglobulin and attenuated mumps vaccine.     

Serologic and molecular evidence for circulation of Crimean-Congo hemorrhagic fever virus in ticks and cattle in Zambia

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne zoonosis with a high case fatality rate in humans. Although the disease is widely found in Africa, Europe, and Asia, the distribution and genetic diversity of CCHF virus (CCHFV) are poorly understood in African countries. To assess the risks of CCHF in Zambia, where CCHF has never been reported, epidemiologic studies in cattle and ticks were conducted. Through an indirect immunofluorescence assay, CCHFV nucleoprotein-specific serum IgG was detected in 8.4% (88/1,047) of cattle. Among 290 Hyalomma ticks, the principal vector of CCHFV, the viral genome was detected in 11 ticks. Phylogenetic analyses of the CCHFV S and M genome segments revealed that one of the detected viruses was a genetic reassortant between African and Asian strains. This study provides compelling evidence for the presence of CCHFV in Zambia and its transmission to vertebrate hosts.     

Comparison of in vitro translation products of Sarcocystis gigantea and Sarcocystis tenella.

Poly(A)+ RNA was purified from cystozoites of Sarcocystis gigantea and Sarcocystis tenella and used to in vitro translate polypeptides in a wheat germ and a rabbit reticulocyte translation system. The in vitro translated polypeptides were compared by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The S. tenella mRNA translated at least two polypeptides (mol. wt about 80,000 and 21,500) in both translation systems that were not translated by the S. gigantea mRNA. To study co-translational and initial post-translational processing in Sarcocystis, the poly(A)+ RNA preparations were in vitro translated in the rabbit reticulocyte translation system in the presence or absence of canine microsomal membranes. Based on electrophoresis, there appeared to be modification of at least some Sarcocystis polypeptides in the mol. wt range 17,000-30,000. In addition, the translation products were immunoprecipitated with a homologous and a heterologous antiserum. The immunoprecipitated polypeptides were compared by electrophoresis and the S. tenella translation products contained at least one unique antigenic polypeptide with a mol. wt of about 34,700 that was not processed by the microsomal membranes. These results suggest that there is at least one polypeptide that is a candidate for use as an antigen for the differentiation of S. gigantea and S. tenella infections in sheep.     

Sarcocystis leporum in cottontail rabbits and its transmission to carnivores.

Muscle from Sarcocystis-infected cottontail rabbits (Sylvilagus floridanus) was fed to coccidia-free cats (Felis domestica) and dogs (Canis familiaris). Only cats became infected and shed sporocysts in their feces. The prepatent period ranged from 10 to 25 days and the patent period from 3 to 46 days. Sporocysts were fully sporulated when shed. They contained 4 sporozoites and a coarse granular residuum and averaged 9.4 by 13.6 micron (N=55). Doses of 200-75,000 sporocysts were orally administered to 5 domestic rabbits (Oryctolagus cuniculus). Domestic rabbits did not become infected, suggesting a strict host specificity for the intermediate host S. floridanus.     

An immunofluorescence test for detection of serum antibody to rodent coronaviruses

An indirect immunofluorescence test, using cultured cells infected with two strains of mouse hepatitis virus, was developed for detection of antibody to rodent coronaviruses. The immunofluorescence test detected serum antibody to mouse hepatitis virus and rat sialodacryoadenitis virus earlier than the neutralization test. In the case of mouse hepatitis virus, the results of the immunofluorescence test closely paralleled those obtained with a commercially available enzyme-linked immunosorbent assay.     

A simple ultrasound test to predict the superstimulatory response in cattle

We tested the hypotheses that: (1) the superstimulatory response is related to the intrinsic number of follicles recruited into a follicular wave; and (2) the number of follicles recruited into a wave is correlated to the number of follicles recruited into the successive wave. A positive correlation will form the basis of a test for predicting the superstimulatory response. Cows (n = 141) were treated with estradiol and progesterone to synchronize follicular wave emergence (first synchronization) and ranked according to the number of follicles > or =2mm at wave emergence to select the upper and lower 10% of the herd. Follicular wave emergence was synchronized again in the high-end (n = 16) and low-end (n = 20) groups (second synchronization), and cows were treated with FSH twice daily for 3 days. High-end cows had a greater number of follicles (P < 0.001) than low-end cows at the time of wave emergence after both the first and second synchronizations in the 2-3 and 4-6mm categories. The numbers of 2-3 and 4-6mm follicles at wave emergence after the first and second synchronizations were positively correlated (P < 0.001; r = 0.77 and 0.71, respectively). Endogenous FSH peak at the time of wave emergence was higher in the low-end group than in the high-end group. Superstimulatory treatment resulted in more than double the number of follicles (P < 0.003) in the 5-7mm and > or =8mm categories in the high-end group than in the low-end group (16.8 +/- 2.2 versus 8.1 +/- 0.9 and 22.7 +/- 4.1 versus 9.7 +/- 1.6, respectively). The number of follicles > or =5 and > or =8mm at the end of superstimulation was positively correlated (P < 0.001) with the total number of follicles > or =2mm at the time of wave emergence after both the first (r = 0.64 and 0.54, respectively) and second ( r = 0.65 and 0.5, respectively) synchronizations. Based on the results of this study, the superstimulatory response can be predicted by the number of follicles > or =2mm at wave emergence. For practical purposes, practitioners can expect the number of follicles > or =5mm after ovarian superstimulation to be approximately 71% of the number of follicles > or =2mm at the time of wave emergence. Results validated the proposed simple ultrasound-based test for predicting the superstimulatory response of individual cows.     

Serologic relatedness between Thy-1.2 and actin revealed by monoclonal antibody

Monoclonal antibodies with affinity for Thy-1.2 on thymocytes also can bind to actin within marsupial, murine, and human cells. A similar cross-reactivity between Thy-1.1 and vimentin was revealed by Dulbecco and co-workers employing monoclonals. A computer-assisted analysis of the amino acid composition provided suggestive evidence for the occurrence of sequence homology between Thy-1.1 or Thy-1.2, actin, and vimentin that likely accounts for the serologic relatedness detected by hybridoma antibodies.     

Studies on Sarcocystis in Malaysia. I. Sarcocystis levinei n. sp. from the water buffalo Bubalus bubalis.

Light and electron microscopic studies and feeding experiments have confirmed the presence of two species of Sarcocystis in the water buffalo Bubalus bubalis. One is the already known species with large macroscopic sarcocysts, Sarcocystis fusiformia (Railliet, 1897) Bernard and Bauche, 1912 and the other is S. levinei n. sp. which is being described in detail. The sarcocysts of S. levinei are 0.9 x 0.1 mm and the zoites in them 17.8 x 4.2 micrometer. Ultrastructurally, the primary cyst wall shows sloping villi with irregular wavy outlines. Within the villi are coarse granules and annulated fibrils. Trabeculae are present. The sexual stages of S. levinei occur in the subepithelial tissue of the small intestine of the dog and sporocysts shed by this definitive host are 15-16 by 10 micrometer.     

Skin test to detect resistance of cattle to Rhipicephalus appendiculatus ticks

The evaluation of a skin test to detect acquired resistance to Rhipicephalus appendiculatus Neumann ticks is described. An extract of salivary glands of partially fed female R. appendiculatus was prepared by dissection, sonication and filtration and used for intra-dermal injection. Tests were carried out on twelve calves of known resistance to R. appendiculatus and on twelve naive calves to establish threshold values for positive reactions. Four rabbits naive to ticks were skin tested repeatedly to assess immunogenicity of the test. Reactions to the test at 1 h and at 24 h after injection were significantly correlated with resistance. The correlation was higher with the reactions at 24 h. Rabbits were immunized by the test but the reactions never exceeded the positive threshold. Further development by field testing is recommended.