Monozygotic bovine quadruplets
H. P. DONALD, W. S. BIGGAR and D. M. LOGAN Animal Breeding and Genetics Research Organisation, Edinburgh Received Io.v.5o ON the 27th January 1949, a Friesian type cow called Peggy, and belonging to Mr William Youngs of Sankence Farm, Aylsham, Norfolk, produced four bull calves. After undergoing considerable publicity for a few days, Peggy died, but the calves survived and were purchased by the Agricultural Research Council, and transferred to the Cattle Breeding Research Farm at Cold Norton in Staffordshire. These calves are remarkable, not only because quadruplets are unusual in cattle, but also because they were born alive, and were all of the same sex. Furthermore, they appear to be the first recorded set judged to be of monozygotic origin. A somewhat detailed account of them, therefore, appears desirable. Unfortunately, two of the calves died a few weeks after purchase, so that a comparison of late developing features became impossible. The evidence on which the diagnosis of one-egg origin is based is as follows. Except where otherwise noted, all remarks apply equally to all four calves.
Causes of variation in the frequency of monozygous and dizygous twinning in various breeds of cattle.
A statistical investigation has been made comprising 12 European cattle breeds with a total of about 5.3 milj. calvings and 120,000 twin births. Season of conception has a marked influence on the frequency of twin births, one maximum corresponding to spring and another one to autumn conceptions. There are significant breed differences in the relation between age of the cows, measured in parities, and the frequency of monozygous (MZ) as well as dizygous (DZ) twin births. On an average, the DZ frequency increases more than the MZ frequency from the first to the fourth-fifth calving; then the age-curves show a plateauing tendency. After the first twin birth, the twinning frequency at the following calvings is 4–5 times higher than in the general population. Apparently, twinning depends on polygenic inheritance and also on various environmental influences, with a threshold for the phenotypic manifestation. It may be assumed that the underlying liability of the cows in a population to bear twins has an approximately normal distribution. The heritability of twinning has been estimated on the binomial p-scale as well as on the x-scale of the normal curve. On the p-scale the heritability of twinning was found to be about 0.02 which corresponds to 0.16 on the x-scale, although with some differences between breeds.
The status of FAO and codex alimentarius developments on vegetable proteins
The FAO is interested in increasing world protein supplies both by advising and assisting developing countries to increase their production of staple foods and by encouraging the development of technology to produce protein concentrates both from vegetable and animal sources to supplement diets which are low in protein content. Recent revisions of the amount of protein required in the diet in relation to total per capita energy requirements and the difficulties encountered in introducing novel foods into established dietary patterns has led FAO to concentrate on increased agricultural productions in developing countries as the primary means of combatting malnutrition. In the meantime, in North America and Europe, advances in the technology of processing vegetable proteins has given highly acceptable products simulating meats which are being used as meat extenders and meat analogues. The consequent increase in vegetable protein production has revealed a need for international, agreement on standardization, and it has been agreed that this will be undertaken by the Joint FAO/WHO Food Standards’ Programme. The program operates chiefly through the Codex Alimentarius, Commission, an international governmental body, the purpose of which is to protect consumers against health hazard in food and against fraud. The Commission, which has 116 member governments, controls an intensive program of work covering the composition, labeling, additives, contaminants, pesticide residues, hygiene, sampling and analysis aspects of foods and has established a procedure which allows member governments ample opportunity to reach agreement on food standards and to accept them for incorporation into national legislation. The Codex Commission, at its 12th session, decided to establish a Committee on Vegetable Proteins with the following terms of references: “to elaborate definitions and world-wide standards for vegetable protein products deriving from soybeams, cottonseed, groundnuts, cereals and from other vegetable sources as they come into use for human consumption, and to elaborate guidelines on utilization of such vegetable protein products in the food supply system, on nutritional requirements and safety on labeling and on other aspects as may seem appropriate.” The question of which country will host the Committee is still under discussion.