The Effect of Unheated Bovine Serum on the Complement-Fixing Activity of Heat-Inactivated Bovine Antiserum with Homologous Antigen. IV. Chromatographic Studies

Unheated, non-dialyzed, normal bovine sera were fractionated by column chromatography on the cross-linked dextran, Sephadex G-25, and the fraction tested for “supplementing” properties, that is for complement-fixation augmenting activities when added to mixtures of heated bovine antiserum and homologous antigen. Supplementing activity was shown by precipitated fractions from earlier eluates with pH values below 7.2 and also by both supernatant and precipitated fractions of the later eluates with pH values from 7.6 to 8.1. The possibility is briefly discussed that certain alkaline protein substances of relatively lower molecular weight may be involved in the supplementing activities of the later fractions. Heating at 56°C. for 30 min. destroyed the supplementing activity of each of these fractions.

Some of the supplementing fractions proved to be anti-complementary, others were not or only slightly so. First component of complement, C¹1, was detected in the precipitated fractions of certain of the earlier eluates with pH values below 6.5; second component of complement, C¹2, was found exclusively in supernatant fractions of earlier eluates with pH values less than 6.2. Conglutinin was not separated from C¹1 by this method.

     

The Effect of Unheated Normal Bovine Serum on The Complement Fixing Activity of Heat Inactivated Bovine Antiserum With Homologous Antigen: II. Aggregative Properties

To determine whether the greater fixation of complement observed in “modified” complement-fixation tests is related to an increased aggregation of the antigen-antibody complexes, parallel tests by the two methods have been made with two different particulate bacterial antigens and corresponding bovine antisera. At the end of the fixation period the mixtures were centrifuged, the supernatant fluids removed carefully, the sediments washed twice and re-suspended in a small volume of buffer. Smears of each sediment were examined by immunofluorescence microscopy using a fluorescein-labelled rabbit antibody for a globulin fraction of fresh guinea-pig serum containing first component of complement.

A greater degree of aggregation of the antigen-antibody complexes was observed in the sediments from tests with modified complement, that is complement supplemented with a diluted bovine serum globulin fraction prepared by dialysis. Aggregates from mixtures showing increased fixation of complement, as determined by titration of the residual hemolytic activity of the supernatant, appeared somewhat more brightly fluorescent.

Very faint or no fluorescence was evident in the stained washed sediments from mixtures of antigen and antibody without complement or from mixtures of antigen, heat-inactivated normal bovine serum and complement.

     

The Effect of Unheated Bovine Serum on the Complement-Fixing Activity of Heat-Inactivated Bovine Antiserum with Homologous Antigen. V. Residual Complement Activity

Complement-fixation tests of three different antigen-bovine antibody systems, two antibacterial and one antiviral, were set up with or without normal bovine serum supplement. At the end of the fixation period all mixtures were tested for whole complement activity and for first, second, third and fourth complement components using the conventional, crude reagents R1, R2, R3 and R4. The increased fixation in mixtures containing the bovine serum supplement mainly reflected a greater decrease in second and fourth component activity than in the antigen-bovine antibody mixtures with non-supplemented complement. The decline in first component activity was relatively less. The results of tests for residual third component activity were not consistent.     

Serological Studies of Parasite Cattle: I. Complement-Fixing Activity of Serial Serum Samples

Complement-fixation (CF) tests with sonicated aqueous extracts of adult forms of five species of gastrointestinal nematodes as antigens have been made on serial biweekly bleedings from two groups of parasitized calves grazing on infected pastures during the 1963 or 1964 seasons. Three of these nematode species, Cooperia oncophora, Ostertagia ostertagi and Nematodirus helvetianus, were found in large numbers in most of these animals. The calves were negative serologically before being placed on pasture but within 2 to 4 weeks some had developed considerable CF activity with Cooperia and other nematode antigens. Ten calves died, however, before significant CF titres had been attained. Eight control calves in the 1963 or 1964 groups which were grazed on “clean” pastures, remained serologically negative during the summer and autumn months. Four of the six surviving exposed animals in the 1964 group showed a fall in CF activity during the winter months when they were stabled, whereas the six surviving controls developed low CF titres suggesting that they were becoming mildly parasitized. In the spring of 1965 CF titres began to rise in some of the previously exposed and control yearlings even before they were placed on infected pasture in June.     

Equine Infectious Anemia: Activity of Liquid Antigen Extracts in the Agar-gel Immunodiffusion and Complement-fixation Tests

Twenty-nine lots of acetone-ether extracted liquid antigen were prepared from the pulp of 11 spleens collected from horses at the acute phase of experimental infection. The lots prepared from the highly reactive pulp resulted in general in a liquid antigen of greater activity than those extracted from weakly reactive pulps. Some variations in activity between lots of antigen prepared from the same spleen were also observed. No matter what the results, given a wide enough variation, all results were reproducible. The procedure permitted production of a greater number of antigen test doses from reactive spleens and rendered usable the spleens which failed to give sufficient reactivity when used as pulp antigen in the agar-gel immunodiffusion test. The activity of each lot of liquid antigen was standardized, first by the complement-fixation test and finally by matching with a reference antiserum in the agar-gel immunodiffusion test.     

热应激生产条件对牛初乳成分含量的影响

（目的）对热应激生产条件下牛初乳中成分含量的变化规律和变化幅度进行了研究。（方法）选用体重、产奶量、分娩El期和胎次相近的热应激和非热应激生产条件下的奶牛各7头。分别于母牛分娩后不同时间内收集乳样，用以分析免疫指标和常规成分。（结果）与非热应激生产条件相比，热应激提高了168h内的蛋白、IgG、pH值，64h后的乳糖含量，降低了168h内脂肪含量、48h内乳糖含量，其中显著提高了2h内IgG、32h内蛋白含量（P〈0.05），显著降低了32h后脂肪含量（P〈0．05），其余差异则均不显著（P〉0.05）。（结论）热应激在一定程度上影响牛初乳成分含量，有关机理有待于进一步研究。     

Studies on Bluetongue: II. Complement-Fxing Activity of Ovine and Bovine Sera

Sera of sheep and calves infected with the California type 10 and Cyprus type 3 viruses of bluetongue were tested by the regular and modified direct complement-fixation tests. To obtain satisfactory complement fixation it was necessary to use the latter test. Cross reactivity was found, therefore, the California type 10 antigen could be used in testing sera of animals infected with the Cyprus virus.     

牛布氏杆菌病热酚法脂多糖抗原酶联免疫吸附试验(ELISA)的研究

采用世界动物卫生组织(OIE)推荐的热酚法提取的脂多糖(LPS)作为抗原，建立了牛布氏杆菌病的ELISA方法，对45份血清进行检测，证明本ELISA方法灵敏性较高，经阻断试验和交叉试验，证明特异性较好。同时对建立的ELISA方法进行了改进，使制备的牛布氏杆菌ELISA试验试剂盒能在4℃条件下长期保存，具有良好的稳定性和重复性。     

Studies on Reproduction in the Goat: III. The Functional Activity of the Ovaries of the Goat

1. A study of the functional activity in the ovaries was undertaken on 366 organs from pregnant goats and 171 organs from nonpregnant goats. The ovulations were recorded by the presence of corpora lutea in the ovaries.
2. The right ovary appears to be the most active in the goat, since 57 % of the ovulations occurred in the right ovary. In cases of multiple ovulations there appears to be a greater tendency for the first of these ovulations to occur in the right ovary (62.34 %).
3. In almost 50 % of twin pregnancies both ova will be shed from the same ovary.
4. In six cases, five twin pregnancies and one triplet pregnancy, only one, respectively two corpora lutea were found. This can in all probability be taken as an indication of the occurrence of identical twins.
5. The incidence of “ovum loss” or early embryonic mortality was found to be 19.6 %.

     

Antigen and Antibody in Aleutian Disease in Mink II. The Reaction of Antibody with the Aleutian Disease Agent Using Immunodiffusion and Immunoelectroosmophoresis

Aleutian disease viral (ADV) antigen was prepared by fluorocarbon extraction of spleen, liver, and lymph nodes from mink experimentally infected ten days previously. Using a potent ADV antigen, antibody was detected by immunodiffusion (ID) and immunoelectroosmophoresis (IEOP). Utilizing these precipitin tests, antibody was detected in all the mink sera tested as early as seven days after experimental infection. Titer of antibody increased throughout the infection period. Titers of more than 100 were reached by 15 days post infection, titers of 1,000 at one month, and titers of more than 5,000 to 10,000 were achieved at two months post infection and thereafter. The immunodiffusion test gave similar or slightly lower titers than those detected by the IEOP.

The IEOP test promises to be a most useful technique for the diagnosis of aleutian disease because it is simple, rapid and specific and is capable of detecting infection early in the course of the disease. It is suggested that this test should be utilized especially for the screening of animals purchased or imported as breeding stock onto ranches.

     

Studies on Diarrhea in Neonatal Calves III. Acid-base and Serum Electrolyte Values in Normal Calves from Birth to Ten Days of Age

A detailed clinical examination was conducted and blood samples were collected from a total of 151 normal calves as soon as possible after birth and at two to three day intervals until the calves were ten days old.

The mean venous pH values for calves from birth to ten days of age was 7.38 ± 0.05.

The mean serum sodium, potassium, magnesium, inorganic phosphate, calcium and chloride ion concentrations in normal calves from birth to ten days of age were 148 ± 13, 5.4 ± 0.8, 2.1 ± 0.4, 4.3 ± 0.8, 5.6 ± 0.5, 95 ±5, mEq/litre respectively. The mean serum osmolality in normal calves from birth to ten days of age was 280 ± 12 mOsm/litre.

     

蛋鸡血清硷性磷酸酶变化规律的研究

本试验以京白Ⅲ系为试验材料,测定了四个时期的血清AL P活性,研究了其变化规律。结果表明,AL P同工酶型快型酶活性显著高于慢型。年龄、同工酶型及年龄×同工酶型互作对AL P活性有显著影响。AL P活性与产蛋量间遗传相关表现为,在生长期为正,而产蛋期为负。四个年龄中,AL P做为间接选择指标,以6周龄为最佳.     

应用MTT比色法评价不同牛血清促细胞生长作用

细胞培养过程中血清的选择对细胞的促生长增殖具有重要作用。本试验分别以商品新生牛血清、自制新生牛血清、自制成年牛血清培养成纤维细胞、骨髓瘤细胞、杂交瘤细胞,通过MTT比色法来判断细胞的增殖能力,进而对血清质量作出评价。结果表明,自制新生牛血清具有良好的促细胞生长作用(相对生长率＞0.96),并且3次试验结果比较差异不显著(P＞0.05),具有较好的重复性;而成年牛血清和无血清空白对照组促细胞作用不明显。因此应用MTT比色法能够评价血清质量。     

应用MTT比色法评价不同牛血清促细胞生长作用

细胞培养过程中血清的选择对细胞的促生长增殖具有重要作用。本试验分别以商品新生牛血清、自制新生牛血清、自制成年牛血清培养成纤维细胞、骨髓瘤细胞、杂交瘤细胞,通过MTT比色法来判断细胞的增殖能力,进而对血清质量作出评价。结果表明,自制新生牛血清具有良好的促细胞生长作用(相对生长率＞0.96),并且3次试验结果比较差异不显著(P＞0.05),具有较好的重复性;而成年牛血清和无血清空白对照组促细胞作用不明显。因此应用MTT比色法能够评价血清质量。