Effects of orvus ES paste on canine spermatozoal longevity after freezing and thawing

Because of weak resistance of canine sperm to freezing, an applicable method of preparing canine frozen semen has not yet been established. We added various concentrations of Orvus ES Paste (OEP) to egg yolk Tris-fructose citrate, and investigated its effectiveness on survival of spermatozoa. Addition of 0.5-1.0% OEP to the extender for freezing canine semen was effective in prolonging post-thaw survival of spermatozoa.     

Isolation of Theileria sergenti piroplasms from infected erythrocytes and development of an enzyme-linked immunosorbent assay for serodiagnosis of T sergenti infections

A method of obtaining a pure suspension of Theileria sergenti piroplasms from infected bovine erythrocytes was developed and the resulting parasites used as antigen in an enzyme-linked immunosorbent assay (ELISA). Piroplasms were freed from infected erythrocytes using the nitrogen cavitation technique and then separated from unbroken erythrocytes by centrifugation at 670 gmax. The parasites in the supernatant were then sedimented by centrifugation at 2700 gmax and the purified fraction examined by electron microscopy. This examination showed that the isolated piroplasms were morphologically intact and that there were few contaminants. SDS-PAGE and spectrophotometric analysis showed that this fraction contained little erythrocyte component. The piroplasms thus obtained were sonicated and treated with Triton X-100 then used for ELISA antigen. The ELISA values had a high correlation with titres obtained using the indirect fluorescent antibody test on sera from cattle infected with T sergenti.     

Enzyme-linked immunosorbent assay using solubilised antigen for detection of antibodies toAnaplasma marginale

An enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies against Anaplasma marginale. A marginale bodies were separated from parasitised erythrocytes by a modified nitrogen decompression method, sonicated, then solubilised with Triton X-100 and used as the ELISA antigen. In this ELISA system the required amount of antigen protein was 16.2 ng for each well. In the course of experimental infections, of calves, significant antibody levels were detected by ELISA and the complement fixation test (CFT) at almost the same time. Antibodies against A. marginale were detectable for longer periods using the ELISA than using the CFT. Sera from calves infected with Babesia bigemina, B. bovis, B. ovata, Theileria sergenti and Eperythrozoon wenyoni gave no reaction; however, antisera against A. centrale did react with the A. marginale ELISA antigen.     

Decrease in erythrocyte survival in Theileria sergenti-infected calves determined by non-radioactive chromium labelling method.

Pathogenesis of anemia in the calves infected with Theileria sergenti was investigated from the viewpoint of erythrocyte survival decrease in the circulating blood. For investigation of erythrocyte survival a method of erythrocyte labelling with non-radioactive chromium (50Cr) was utilized. It was found that (1) the erythrocyte survival decreased markedly in the T. sergenti-infected calves compared with that in the uninfected calves; the survival rate of 25.7% for infected calves and 86.0% for uninfected ones on the fourth day after re-introduction of the labelled erythrocytes into the original donors, and that (2) the survival of non-parasitized erythrocytes in the infected calves was also decreased, which indicates no obvious relationship between parasitism and decrease in survival of erythrocytes.     

Selective medium containing fosfomycin, nalidixic acid, and culture supernatant of Rhodococcus equi for isolation of Corynebacterium pseudotuberculosis.

FNR medium containing fosfomycin, nalidixic acid, bovine blood and culture supernatant of Rhodococcus equi was prepared by the present authors, and the medium did not inhibit growth of Corynebacterium pseudotuberculosis but completely hampered the growth of Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. The culture supernatant of R. equi facilitated detection of suspected colonies of C. pseudotuberculosis due to synergistic hemolysis. Rate of isolation of the organisms (from the trachea, larynx and nasal cavity of 16 slaughtered sheep with caseous abscess in the lung) was higher with FNR, the selective medium, than with nonselective medium. The selective medium was thus found to be useful for isolation of C. pseudotuberculosis from sheep.     

Immunoglobulin M associated with secretory component and immunoglobulin A deficiency in bovine colostrum.

Immunoglobulin (Ig) M purified from bovine colostrum was examined by an immunodiffusion analysis with antisecretory IgA serum and was found to be associated with a secretory component. Some of the combined proteins were dissociated if treated with 5 M guanidine-HCl and others were not. Another immunodiffusion analysis of 23 specimens of colostrum led to the finding that certain colostrums were deficient in IgA, even though they contained IgG and IgM.     

Angioarchitecture of the Branchial Arterial System of Carp (Cyprinus carpio L.)

The arterial system of the gills of carp and its histological structure were studied light and electron microscopically by making Mercox or Neoplane Latex corrosion cast preparations. Four pairs of afferent and efferent branchial arteries, and a pair of afferent and efferent pseudobranchial arteries were identified in the branchial arterial system. The 1st and 2nd afferent branchial arteries are given off directly from the ventral aorta, and the 3rd and 4th afferent arteries originate from their common trunk, which is branched off from the ventral aorta caudal to the origin of the former branchial arteries. Numerous afferent filamental arteries are connected to the lamellar blood capillary networks in the gill lamellae via afferent lamellar arterioles, and efferent filamental arteries followed the efferent lamellar arterioles are converged into four efferent branchial arteries that are connected to the dorsal aorta. To the pseudobranchia, afferent pseudobranchial arteries are connected with the ventral branches of the 1st efferent branchial arteries to provide arterial blood to the organ through the afferent mandibular arteries. Afferent pseudobranchial lamellar arterioles originating from the afferent pseudobranchial filamental arteries are connected with the blood capillary networks in the pseudobranchial lamellae, and blood in the capillary networks is drained into the efferent pseudobranchial filamental arteries via 2-4 pseudobranchial lamellar arterioles. Branches of the efferent pseudobranchial filamental arteries are connected with the arteries to the eyeballs and provide blood to choroid of the vascular tunic of them. Pseudobranchial cells surrounding lamellar capillaries in the pseudobranchia are furnished with abundant mitochondria and tubular structures, and the histological findings suggest the cells may share an ability to exchange physiological materials between the cells and the blood in the capillary networks of pseudobranchia.