636 SECTIONAL TRANSACTIONS.— M. 



it seemed probable that nutritional variation is also responsible. As protein and 

 calcium are known to be essential for young growing animals, it was decided to 

 investigate the effect of deficiencies of these constituents on breeding sows. Three 

 pens of female pigs were placed under experiment on rations which were, respectively, 

 complete, deficient in digestible crude protein, and deficient in calcium. Two-thirds 

 of these pigs were slaughtered at the end of the third month of pregnancy (gestation 

 lasts four months) and the remainder allowed to farrow. The offspring were reared 

 on the same ration as the dams, the male pigs were removed from experiment at 

 weaning, and the remaining female pigs dealt with as the first generation. The 

 experiment lasted for 3J years, during which time the following observations were 

 made. 



The pigs on the complete ration formed an effective control. They grew more 

 rapidly, bred more regularly, and remained in better health and freer from accidents 

 than the other two pens. The progress of the pigs on the protein- deficient diet was 

 very greatly retarded, partly owing to a very slow rate of growth in the earlier stages 

 and partly owing to interference with breeding. Among the pigs on the calcium- 

 deficient ration the most obvious features were, first, the large proportion of accidents 

 occurring, and also the increasing amount of ill-health and deaths amongst the 

 sucking and newly weaned pigs. 



A steady rise in numbers of atrophic fcetuses from slaughtered sows in the complete 

 pens as compared with the small numbers in the other pens showed that some factor 

 other than a deficiency of protein or calcium was partly responsible. A comparison 

 of the figures at birth on the other hand showed a very definite increase of dead pigs 

 in each successive generation on the calcium-deficient diet. The average live weight 

 at 16 weeks of the complete pigs fell from 56 lb. in the first generation to 34 lb. in 

 the third, whereas with the calcium- deficient pigs the first generation weight was 

 49 lb., and the third litter of the second generation only 13 lb. 



As the experiment progressed, the return of oestrus after weaning tended to be 

 delayed on the protein-deficient ration, whereas on the calcium-deficient diet the most 

 noticeable progressive observation was the lack of udder development and the 

 apparent starvation of the sucking pigs. Deaths from broken bones and from 

 peritonitis following injury at service were observed only in the calcium-deficient pigs. 

 It is suggested that the investigation points to the following conclusions : 



(1) Foetal atrophy is not directly caused by a deficiency of protein or calcium in 

 the food of the sow. 



(2) A serious deficiency in the body supply of protein or calcium in the pig requires 

 one or two generations to become established. 



(3) Calcium deficiency leads to an increasing reduction of the milk supply in sows, 

 coupled with an increasing number of pigs born dead. The combination of these two 

 results leads to extinction after two or three generations. 



(4) Protein deficiency when vitamins and mineral salts are adequate produces 

 very marked reduction in rate of growth and probably in rate of breeding, but does 

 not lead to lack of milk supply, increase in disease, or to deaths at birth. 



Mr. J. A. Eraser Roberts. — Wool Research and the Farmer. 



Many aspects of wool production present a favourable field for scientific research. 

 Although in this country wool is a secondary product of agriculture, it is nevertheless 

 one in whose sale the farmer has a direct interest. Equally as it is a by-product, it 

 is to be expected that the gap between the producer and the consumer would be 

 wider than usual. This tendency is made more marked owing to the rapid changes 

 of fashion which make the demand fluctuating and variable. The result is that 

 there is probably no field in agricultural production where the interests of the consumer 

 are less studied. There is an exceptionally favourable field for scientific research 

 designed to standardise and to classify and so make possible an attempt to bridge 

 that gap. 



To the breeder the fleece is more than a saleable commodity ; it is an efficient 

 covering, or otherwise, intimately connected with the well-being of the animal. Also, 

 as wool in this country is not the main aim of sheep-breeding, any indirect connexion 

 with other important qualities is of importance. 



This paper is an attempt to show how research on wool can be of assistance to the 

 farmer in these and other directions. 



