The Semen of Animals and Artificial Insemination

Abstract

The first 143 pages, together with 40 pages of references by D. R. Melrose deal with artificial insemination of cattle. His selection of references shows fine judgment, little significant work failing to receive mention, and he has expended much effort in assimilating this information, reconciling reports which appear to conflict and expressing results in a form which although readily appreciable, nevertheless constitutes a text which will be useful even to specialist workers. No aspect of actual or potential importance has been overlooked; thus, the chapter on deep freeze conservation deals, inter alia, with technique of freezing, methods of storage, length of storage possible, variation in results between bulls, practical applications, effect on pathogenic organisms in semen, and freeze-drying. The first 5 chapters appear over-compressed in style (possibly a result of length limits imposed by the editor). In listing textbooks two British volumes are included which are respectively very brief and largely devoted to infertility; both were published over ten years ago, whereas the massive and comprehensive German work by K. Eibl (1959) is ignored, as is similarly, in a later chapter, the striking success obtained by this worker with the Illini variable temperature diluent Eibl & others (1959) Dtsch. tierärztl. Wschr. 66, 1]. There is little detail of rations to be fed to bulls or of the health tests applied to them, and Debruyne's remarkable results (1961) on collection from bulls by rectal massage are not discussed, probably because they appeared too late. Sections on the buffalo, sheep and goat, of 21, 47 and 11 pages, are contributed respectively by P. Bhattacharya, C. W. Emmens with T. J. Robinson, and J. Blokhuis. In general these maintain a high standard of scholarship and they contain information even less readily available elsewhere than is that in the cattle section. The sheep section includes a thoughtful assessment of the actual and potential economic importance of A.I. ; its extension is linked to an important extent with collectivization in Communist countries, but if the technical problems involved in deep freezing should be solved the position would change. The buffalo differs from the bull to a surprisingly great extent. Infertility in male goats is reported by Blokhuis to be very prevalent in Germany, with spermiostasis as the most common cause, he is non-committal about its aetiology and does not refer to reports V.B. 29, 573] that it is due to a malformation resulting from a recessive gene. L. E. A. Rowson has written a characteristically terse chapter on the pig; it occupies only 18 pages which seems very little in view of increasing interest in this aspect of A.I., but this contribution is particularly well-digested and the information content per page is high. The current rapidity of advance presents the publisher with a problem. P. W. Swire contributes 23 pages on insemination of Equidae and provides good cover of the literature, much of it of Slavic origin. This author appears to place undue emphasis on horses for sport and pleasure, ignoring that the working horse population is large and rising in Spain, Greece, Turkey, Yugoslavia, Norway and Sweden besides the widespread use general in the Communist countries FAO Agri./Mech. 9, United Nations, Geneva, 1958]. Mule breeding Swire considers, by implication, still to be an economic proposition, but there is no reference to the massive activity in equine A.I. in China Chen, P. L. IVth Int. Congr. Anim. Reprod., The Hague, 1961]. While the space-allocation for the pig and the horse appears meagre, that for the dog, of 12 pages, is almost too generous, but A. E. Harrop has produced a particularly readable and interesting chapter, including many previously unpublished data (but no photograph of the vaginal smear which can be important in deciding when to inseminate). Chapters on rodent and bird insemination maintain the high general standard. The penultimate chapter on tropical conditions presents a salutary reminder that life is still precarious from day to day for the majority of the human race, but A.I. is helping to render it less so. The serious "sluggish bull" problem in Bos indicus is in a fair way to solution by means of electro-ejaculation.-F. L. M. DAWSON.