Lamb Serum Research Articles

Lactic dehydrogenase isoenzymes in tissues and serum of normal and dystrophic lambs.

SummarySerum from lambs with nutritional muscular dystrophy showed increases in all 5 forms of lactic dehydrogenase (LDH). The largest percentage increase occurred in LDH V, followed by isoenzymes IV, III, II and I. The largest absolute increase was in LDH III. Therapy with vit. E alone or with vit. E plus selenium restored normal levels of all isoenzymes. Treatment with selenium alone diminished serum LDH only temporarily. Data are presented for the LDH isoenzymes in lamb tissues. Skeletal muscle from dystrophic lambs showed a decrease in the percentage of LDH V and increases in the percentages of the other LDH forms. The other tissues from dystrophic animals showed an essentially normal LDH isoenzyme distribution.

Pathologic and immunologic responses of the fetal lamb to Brucella ovis.

Ewes were exposed to live Brucella ovis either by the intrauterine or the intraconjunctival routes prior to breeding, at breeding and at various stages of gestation. Serological and immunochemical analyses were performed on all ewe and lamb sera and gross and microscopic examinations were made of fetuses. Infections of fetuses in the ewes exposed intraconjunctivally were confined to those groups exposed between 3 and 12 weeks post breeding. Intrauterine exposures indicated (1) that the organism does not appear to remain in the nonpregnant uterus for any extended length of time, (2) probably causes the death of the ovum and embryo, and (3) fetuses of 6 weeks of gestational age are able to withstand the microbial invasion for extended periods of time. All fetuses exposed in utero from the sixth post breeding week to term were infected, as determined by immunological, bacteriological and pathological examinations. Regardless of the route of inoculation, lesions of the infected fetuses were found in the placentas, lungs, lymph nodes, kidneys, livers and intestines. Alterations in the spleen were limited to the formation of follicles with secondary centers and increased RE activity in the cords of the red pulp. Brucella ovis was recovered most frequently from the lungs and occasionally from the abomasums and a spleen. All but one of the infected fetal lambs had elevated gamma globulin levels and complement fixation titers for Brucella ovis.

THE EFFECT OF DIFFERENT SERA IN THE CULTURE MEDIUM ON THE BEHAVIOR OF PLASMODIUM BERGHEI FOLLOWING SERIAL PASSAGE THROUGH TISSUE CULTURE.

SYNOPSIS. A previous study has shown that a strain of Plasmodium berghei had become modified following serial passage through rats and tissue culture in a medium containing lamb serum. Mice infected with this strain showed a longer survival time and some of the mice recovered. The recovered mice developed a true immunity to reinfection with the modified strain and the parent strain. It was thought that this effect was due to the serum contained in the culture medium. Consequently the experiments were repeated and other strains developed using rat and calf serum. The strain derived, after 10 serial passages alternately through rats and tissue culture containing rat serum, retained the characteristics of the parent strain, i.e., all mice infected with this strain died; the majority within 19–21 days. Mice infected with a strain derived from the series utilizing calf serum showed a significantly longer survival time and 8 mice out of 87 survived. The strain derived by using lamb serum yielded results similar to those previously reported and after 8 serial passages 20 mice out of 65 survived infection. The hypothesis is advanced that P. berghei is antigenically heterogeneous, much as has been shown for the trypanosomes. It is thought that opsonins contained in the serum of the tissue culture medium render certain antigenic types more liable to phagocytosis and therefore the in vitro treatment acts as a screening process, as the case might be, leaving those types most easily recognized by the mouse and hence evoking an effective immune response.

Effect of x-rays on plaque-forming ability of vesicular stomatitis virus.

A quantitative study was made of the plaque-forming ability of vesicular stomatitis virus when irradiated under a number of conditions suitable for the quantitative estimation and subsequent isolation of plaque-type variants. Investigations were made onthe effects of x rays on plaque-forming ability of virus: irradiated and diluted in phosphate buffered saline; irradiated in phosphatebuffered saline and diluted in modified Hank's solution, containing 0.5% lactalbumin; irradiated and diluted in 1 and 10% nutrient broth; and irradiated and diluted in 20% lamb serum. It was concluded that virus irradiated in broth was not only less sensitive to inactivation but also formed principally round plaques, while virus irradiated in buffer produced normal, ragged, and minute plaques. The resuIts show that irradiation in buffer may provide the most convenient means for the procurement of plaquetype variants. (P.C.H.)

An analysis of proteins in the serum of maternal and foetal sheep and the lamb by paper electrophoresis.

The proteins of pregnant and foetal sheep and newborn lamb serum were examined by paper electrophoresis. The following changes in serum protein constitution were observed in foetal serum between 81 and 129 days of gestation and in newborn lamb serum up to 19 days after birth:

抗水酸化アルミニウム処置血清蛋白沈降素の特異性に関する研究補遣

1) In case of antiserm as the antigen of bovine serum and its serum protein fractions, the quantity of preciptin seems to be increased more with addition to a number of injection and with this fact appears the non specific side reaction. Of the side reaction, the lamb serum reacts less strongly than bovine serum, the chief antigen because of the closeness of the zoological relationship; the serums of swine, horse and human react less strongly than the lamb serum. And it has been noticed that these antiserum are difference with one another in their side reaction.2) The increase of side reaction and quantity of precipitin can be confirmed the difference in case of immunized injections once and three times, but not in case of five and times. The chief precipitin titer becomes the highest in case of immunized injection five times bnt afterwards it does not get high remarkably according to the increase of times of immunized injection.3) The side precipitin titer and quantity are always lower than that of chief according to the repeated injection used as an antigen, there are difficult to be distinct the chief and side reaction with only precipitin titer, however are clearly distinct with precipitin quantity.4) Immunized with bovine serum protein fractions, the antigenity is higher than that of bovine serum itself. And antigenity of albumin is not less than that of other patterns and race speciality is intensive.5) The substance of the non specific side reaction in case of antigen of injected bovine serum exisits in the protein which to the euglbulin and pseudoglobulin frsctions, and seems to be more in pseudoglobulin.6) The side reaction appears more clearly, according to the increase of chief precipitin quantity in case of the antiserum of the same soecies, and according to the increase of the frequency of the occurrence of the complex stair-like “form of reaction field” in the case of the antiserum that has the same precipitin quantity.

Electrophoretic Patterns of Lamb Serum Before and After Transfer of Colostrum

THE increase in the serum globulins resulting from the ingestion of colostrum has been demonstrated by Howe1 and also by Schneider and Szathmary2, who employed precipitation methods. Jameson and Alvarez-Tostado3 also employed electrophoretic analysis to demonstrate such an effect when cow‘s colostrum is fed to man or the adult rat ; and, with Sortor4, they have studied calf serum at birth and at subsequent times. Similar investigations have now been made in connexion with the passive immunity produced in lambs by the transfer of colostrum.