1918] 



DAIRY FARMING DAIRYING. 



377 



production record of the 10 highest producers of milk and milk fat, the more 

 prominent families, and the performance records of a number of leading bulls 

 of each breed are also given. The average production for cows that have com- 

 pleted yearly records for advanced registry is shown in the following table: 



Average production of cows completing yearly records for advanced registry. 



Breed. 



Ayrshire 



Brown Swiss 



Guernsey 



Holstein 



Jersey 



Number 

 of cows. 



2,5S8 

 199 

 6,200 

 3,220 

 5,244 



Milk pro- 

 duction. 



Pounds. 



9,555.00 

 10, 868. 70 



8,934.44 

 14, 622. 70 



7, 792. 00 



Fat 

 content. 



Per cent. 

 3.950 

 3.995 

 4.990 

 3.424 

 5.350 



Fat pro- 

 duction. 



Pounds. 



877.51 

 433. 45 

 466. 01 

 500.70 

 417.00 



[Milk preserved with formalin for calves], H. Welch {Montana Sta. Rpt. 

 1916, p. 182). — Seven calves from one to two weeks old were fed skim milk 

 to which enough formalin had been added to keep it sweet for four to six days 

 at temperatures averaging 80° F. As a check, seven calves were fed on un- 

 treated skim milk. During the six weeks of the test the two lots gained equally 

 in weight, and the calves on formalin-preserved milk were in every way as 

 thrifty and healthy as the other lot. 



The milking machine as a factor in the production of sanitary milk, G. L. 

 A. RuEHLE, R. S. Breed, and G. A. Smith (Amer. Jour. Pub. Health, 7 {1911), 

 No. 10, pp. 840-S-i6). — Results of bacteriological analyses seem to show that 

 the machines on the market can be successfully used to produce more sanitary 

 milk than that obtained by hand milking. 



Belationship of milk supplies to typhoid fever, W. H. Feost {Pub. Health 

 Rpts. [U. S.], 31 {1916), No. 48, pp. 3291-SS02; abs. in Abs. Bad., 1 {1917), No. 

 5, pp. J/IO. 411). — This paper calls attention to the deficiency of our knowledge 

 of the relationship between milk supplies and the prevalence of typhoid fever. The 

 author suggests that the influence of a milk supply in disseminating typhoid 

 fever is determined by (1) the sources of infection to which the milk is ex- 

 posed, (2) the opportunities afforded for infective material to be introduced 

 into the milk from these sources or the precautions taken to safeguard against 

 the introduction of infective material, and (3) circumstances affecting the 

 potentiality of the milk supply in disseminating infection after infective mate- 

 rial has once been introduced. Opportunities for estimating the influence of milk 

 supplies upon typhoid prevalence are pointed out. 



Some observations on the bacterial examination of milk, F. H. Slack 

 (Atner. Jour. Pub. Health, 7 {1917), No. 8, pp. 690-697; abs. in Abs. Bad., 1 

 {1917), No. 5, p. 411). — The author concludes that incubation of milk plates for 

 48 hours rather than 24 hours is advisable, since, on an average, the count is 

 doubled or trebled. The use of meat extract media for milk counts should be 

 abandoned, since it gives lower counts and the colonies are much smaller than 

 vith media made from fresh beef juice. A preliminary microscopic estimate of 

 the number of bacteria in a milk sample by the smeared sediment method is 

 advisable, (1) to rule out specimens of low bacterial content on which no fur- 

 ther work need be done, and (2) to judge the proper dilution for specimens 

 which must be plated. 



A safe and sane milk supply, J. Weinzibl {Proe. 2. Pan Amer. Set. Cong., 

 1915-16, vol. 10, pp. 127-130). — It is stated that pasteurized milk, when the 

 process has been properly carried out, is safe so far as disease is concerned. 



