Ram spermatozoa were stored at 5 degrees C in diluents containing various fractions of egg yolk prepared by dialysis, ultrafiltration and ion-exchange chromatography. They survived storage best in the presence of components of egg yolk which were non-dialysable and were not filtered through membranes which retained substances of molecular weight greater than 100 000. The substances isolated in peak B of the ion-exchange chromatogram of whole egg yolk described by Seideman et al. (1969) gave greater protection than those from other fractions from this chromatographic system. These data indicate that the low-density lipoprotein fraction of egg yolk is the most likely source of protection to ram spermatozoa against the effects of storage at 5 degrees C.

Analysis of Variance↗

PubMed1975

Effects of egg yolk, glycerol and the freezing rate on the viability and acrosomal structures of frozen ram spermatozoa.

The influence of egg yolk, glycerol and the freezing rate on the survival of ram spermatozoa and on the structure of their acrosomes after freezing was investigated. Egg yolk was shown to be beneficial not only during chilling but also during freezing; of the levels examined, 1-5% gave the greatest protection. Although the presence of glycerol in the diluent improved the survival of spermatozoa, increasing concentrations produced significant deterioration of the acrosomes. With closely controlled linear cooling rates, no overall difference was detected in the survival of spermatozoa frozen at rates between 6 and 24 degrees C per min. However, a significant interaction between freezing rate and the inclusion of glycerol in the diluent showed that glycerol was less important at the highest freezing rate. A sudden cooling phase near to the freezing point following the release of the latent heat of fusion was not detrimental to spermatozoa.

Acrosome↗

PubMed1975

Implications of phenothiazine side effects: a study of antiparkinsonian agents in an older population.

A study of anti-Parkinsonism agents in prolonged phenothiazine therapy seeks to clarify some anecdotal misconceptions. Antiparkinsonian agents do not appear to affect the therapeutic efficiency of phenothiazines, nor does using them on a "demand" basis increase the problems of control of parkinsonian side effects. Older patients, however, appear to require the extended usage of antiparkinsonian agents rather more than some studies would suggest. Sustained release antiparkinsonian agents may yet further simplify the management of schizophrenia.

Adult↗

PubMed1974