1030 Summary of Agricultural Experiments, [march, 



taken as an index of the well-being of the birds, which had been very 

 carefully selected to secure equality, and the result showed that in 15 

 weeks the hens in House No. 1 laid an average of 38*8 each, while 

 those in No. 2 laid only 28*5 each. The birds therefore did better when 

 the air was changed only five times per hour, and the difference is 

 attributed to the smaller loss of heat by the birds, which shows itself in 

 production. 



It is concluded, therefore, that it is desirable that each bird should 

 be allowed 40 cubic feet of air per hour, and that this 40 feet should 

 be supplied at a reasonably slow rate. Under conditions known by 

 experience to be favourable to the birds, the air changes in a large 

 house four times, and in a small house five times, per hour, which 

 appears to be a very suitable rate. 



Dr. Russell observes that it is clearly impossible for the practical 

 man to test the air in his poultry houses and ascertain the amount ol 

 carbonic acid present, nor is there any necessity to do this, because, 

 under similar circumstances, the amount does not show a very great 

 variation. The above conditions are all fulfilled in houses of a more 

 or less cubical shape and also in the low types of house, when (a) there 

 is a floor allowing a certain amount of air to enter from below, e.g., 

 bricks about a quarter-of-an-inch apart covered with peat moss, or 

 spaced boards if the floor is of wood ; (b) there is top ventilation, two 

 inches being open under the eaves of a high house, or a few large holes 

 bored in the sides of a low house; and (c) each bird is allowed ten 

 cubic feet of space. 



Cost of Rearing Ducklings (Univ. Coll., Reading, Agric. Dept.) — A 

 trial was carried on in 1908 to ascertain the cost of rearing ducklings 

 up to nine weeks old, and was reported in this Journal, December, 1908. 

 The average cost was found to be about 15. 5^. 



Diseases of Live Stock. 



Causation and Spread of Anthrax (Aberdeen and N. of Scotland 

 Coll. of Agric. Bull. 9.) — The prevalence of anthrax in the county of 

 Aberdeen suggested an inquiry into its causation and spread, and the 

 information obtained during four years is contained in this report. 

 The conclusion arrived at by Mr. McLauchlan Young is that anthrax 

 occurs more frequently in sheep than is generally known, and is more 

 likely to appear in feeding sheep than in hill or wintering sheep. 

 The disease, moreover, is seldom looked for in sheep, and precautions 

 are seldom taken in disposing of the carcases of animals that have 

 died, so that there are many opportunities for the infection of other 

 animals. Mr. Young makes, in this connection, some suggestions as to 

 precautionary measures. 



Diseases of Sheep (Journal of South-Eastern Agric. Coll., No. 17, 

 1908.) — Experiments have been carried out by Mr. T. W. Cave, 

 F.R.C.V.S., with cultures of the braxy and louping-ill organisms 

 dealt with in the Report of the Departmental Committee of the Board 

 of Agriculture on those diseases. These cultures were employed by 

 Mr. Cave with a view to protecting the sheep of Romney Marsh 

 against the attacks of the " struck " organism, but no conclusive results 

 were obtained. 



Mr. Cave also records an investigation into the nature and cause 



