1917] DAIRY FARMING DAIRYING. 373 



A good bull's influence upon three generations, J. J. Dunne {Hoard's 

 Dairyman, 5S {1911), No. 12, pp. 518, 519).— For the purpose of showing the 

 value of cow-testing records, production records are given of the offspring of a 

 number of bulls in one family in Denmark, indicating in general that the in- 

 fluence of these sires was good. 



The fat content of the milk of the offspring was almost always increased, 

 and in many cases the amount of milk was increased, as compared with their 

 dams. It is stated that " when the average milk yield and fat percentage of 

 a herd are lower than those inherited by the bull from his dam and grand- 

 dams, the offspring resulting therefrom will be found to have, in the majority 

 of cases, more milk and a higher fat percentage than their dams. On the other 

 hand, when the milk and fat records of a herd average higher than those in- 

 herited by the bull, the opposite is generally the case." 



The yield and composition of cows' milk during lactation, R. A. Bekby 

 (West of Scot. Agr. Col. Bui. 76 (1916), pp. 49-73, figs. 6).— The author gives 

 results of a preliminary study of the effects of individuality on the changes 

 in the yield and composition of milk during lactation as shown in the case 

 of three cows. 



The effect of advance in lactation on milk yield followed much the same 

 order of variation in the case of two of the cows, but differed greatly in the 

 third. Data from the milk records of a large number of cows show that the 

 milk yield generally rises for the first two months after calving, after which 

 it falls more or less regularly until the end of the lactation period. These milk 

 records also show that the fat content of the milk generally falls in the second 

 month after calving, followed by a gradual rise thereafter. With one of the 

 three cows under observation the fat content of the milk showed little variation 

 throughout the lactation period. Apart from the normal effects due to ad- 

 vance in lactation, the fat content of the milk of the other two cows was ap- 

 preciably Influenced by change of environment and feed. Other changes in 

 the milk and milk fat of the three cows due to advance in lactation are dis- 

 cussed. 



Notes on modem dairy chemistry, W. van Dam (Opstellen over Moderne 

 Zuivelchemie. The Hague: Alg. Nederland. Zuirelbond, 1916, pp. 180, figs. 

 12). — This volume discus.ses the true acidity of milk and its effect on curdling; 

 the antiseptic action of the acidityof whey used for feeding ; the influence of the 

 hydrogen ion concentration on the growth and destruction of colon and typhoid 

 bacilli ; the action of microbial lipase in relation to the true acidity of dairy 

 products ; erroneous ideas in regard to the acidity of cheese mass ; acidity of 

 the curds of Edam and Emmental cheese and its significance ; relation of acidity 

 to cheese ripening; the influence of temperature on the physical condition of the 

 milk fat ; the preparation of Edam cheese, using pepsin in place of rennin ; and 

 closely related topics. 



Cream production and grading in Kansas, G. S. Hine {Kansas Sta. Circ. 

 56 {1916), pp. 4< fig- 1)- — Brief essentials are outlined. 



The changes in the composition of Cheddar cheese during the process 

 of ripening, R. A. Berky {West of Scot. Agr. Col. Bui. 16 {1916), pp. 7^-78). — 

 The Cheddar cheese used in this preliminary experiment was made from milk 

 in which a pure culture of Streptococcus lacticus was used as a starter. 



Due to a continuous loss of water the total nitrogen showed a gradual in- 

 crease from the beginning to the end of the ripening period. The water-soluble 

 compounds rose from about 3 per cent of the total nitrogen in the green cheese 

 to 37 per cent by the ninth month, when the experiment ended. There was also 

 a small but persistent rise in the amount of the ammonium compounds. No 



