682 EXPERIMENT STATION RECORD. [Vol. 35 



hemolytic streptococci of human origin produce mastitis in cows when injected 

 directly into the milk ducts. 



" This mastitis may be severe, leading to a caked bag and later to a chronic 

 inflammatory condition which results in an atrophy of the mammary gland. On 

 the other hand, virulent hemolytic streptococci may grow and multiply in the 

 milk ducts of a cow without causing any visible changes in the udder. The 

 milk, however, . . . contains hemolytic streptococci and an increased number 

 of leucocytes. These infections may persist over long periods of time in the 

 form of a chronic mastitis. 



" Streptococcus lacticus of the type used in these experiments produces a very 

 acute inflammation of the udder when cultures are injected directly into the 

 milk ducts. This infection . . . was of short duration and left the gland 

 functionally unchanged. A nonpathogenic hemolytic streptococcus of the type 

 commonly found in normal milk may give rise to a transitory inflammation of 

 the udder when injected directly into the milk ducts, producing a mastitis 

 similar in every detail to that produced by nonhemolytic S. lacticus. The pres- 

 ence of pathogenic streptococci and an increased number of leucocytes in milk 

 is indicative of a mastitis, and may be the sole indication of mastitis. 



" The quarters of a cow's udder under experimental conditions are apparently 

 separate as regards infection. One quarter may be infected, while the others 

 remain normal. Examination of the milk from each quarter of the udder is 

 necessary before mastitis can be excluded in a suspected cow. 



" In three instances of bovine mastitis, all of which were due to hemolytic 

 streptococci with all the characteristics of the human types, no noteworthy 

 changes in the morphology or cultural characteristics of the invading organisms 

 were observed in frequent examinations of the milk throughout the course of the 

 infections. The distinguishing characteristics primarily noted for each organism 

 were still present at the last observation, and there were no modifications 

 which might be considered as indicating a change from one type to the other. 

 The cultural and morphological characters of S. lacticus and of the hemolytic 

 streptococcus derived from normal milk did not change during the cour.se of 

 the udder infections which they induced." 



Control and eradication of infectious mastitis in dairy herds, H. Moak 

 {Cornell Vet., 6 (1916), No. 1, pp. S6-4O). — Considerable success has been met 

 with in the control of this disease by dipping the teats after milking in a 

 weak solution of one of the newer high-powered antiseptics, pyxol, wescol, or 

 hycol (one teaspoonful to 3 pints or 2 qt. of water), for six or seven seconds. 

 Reports from several herds affected with mastitis state that from the time this 

 treatment was started 10 new cases developed. The practice is now made 

 obligatory on 12 farms furnishing certified milk for Brooklyn, N. Y. 



Effects of feeding cotton seed and its products to swine, G. A. Roberts 

 (Jour. Amer. Vet. Med. Assoc, 49 (1916), No. 1, pp. 12-17).— A digest of in- 

 vestigational work of the several divisions of the North Carolina Experiment 

 Station during the past six years. 



" While several agents [sulphate of iron, ashes, etc.] have proved efficient 

 in prolonging the period of safe feeding of cotton-seed meal no practical means 

 for eliminating the toxic element, or elements, has as yet been developed. The 

 writer believes that the effect of the above agents is purely chemical in render- 

 ing the gossypol, and possibly other toxic substances, nontoxic. He has noted 

 with others that hogs having range and rooting a great deal apparently gain 

 minerals from the soil and forage which enable them to withstand the cotton- 

 seed meal longer than when confined, especially when on a board floor. Since 

 iron salts did not prevent all deaths, and that a number of iron-fed swine devel- 

 oped conspicuous rheumatic symptoms, the writer does not believe iron to be 



