1919] ANIMAL PBODUCTIOH. 873 



given in the Resistor of Merit of Jei attle were c-h. -slil.-a acfiOBdlag to age 



at test, and the coeffletenta of oorrelatfoB between More and annual milk ; 



dnction for each age are computed. As tabled thee >fficlents are all m 



tive except for the 9 year-old class, but only in the two younge 

 they sensibly different from zero considering the probi 



relation for heifers between i.r> and L'.r. yean la about 0.21, and tor tb be 



tween 2.5 and :'..") years —0.31. in each ease the probable error i> approxlmati 

 0.05. The author interprets these data as Indicating a certain ■access on 

 part of the judges in picking high-producing 2-year-olds. 



Breeding experiments. — A previous account ( K. S. I;., 40, p. 7.". i of s-mie re- 

 sults of the experimental cattle crosses is summarized and Information Riven as 

 to the ancestry of 14 crossbred calves not hitherto listed. Seven unpublished 

 photographs, four of them colored, are given of the experimental animals to 

 show the segregation of black and fawn after a Jersej Elolstein cr< 



Inheritance of ttoinning and problems connected then ;<itii. This is a new 

 project, and data are being accumulated bj ihe questionnaire method. 1 

 form sent out is reproduced. It is stated that a freemartln in the crossbred 

 herd came into heat when about 20 months old and took the bull normally, 

 although autopsy later showed lack of ovaries. 



Cooperative cuttle breeding records. — Collection of these records has ended 

 and the study of the data is under way. some Of the results being summarized. 

 The average birth weights (with probable errors) of eight breeds are tabulated. 

 The average length of normal gestation shown by 1,197 records is 281 days, 

 15.75 hours. Half of the records are Included between 277 and L!SG days, and 

 all of them between 215 and 315 days. 



Of 21 twin births recorded 3 pairs were both males, 14 bisexual, and 4 both 

 females. Adding these data to those of Lillie (E. 8. I!.. t<>. p. 466) make-, ;•- 

 pairs of the same sex and 38 of opposite sexes, a result which, combined with 

 unpublished studies on the resemblance of bovine twins, is held to Indicate 

 absence of identical twins in cattle. In man, where identical twins do occur, 

 the available data show 1.7 pairs of the same sex to one of opposite « 



Earlier studies 1 on the Interval between observation of heat and time of 

 service are augmented and tabulation is made showing the relation between 

 this interval and conception. Unsuccessful services occurred most frequently 

 very early or very late in beat, and it is concluded that the most successful 

 time was between 5 and 10 hours after beat was observed. The choice of time 

 had no influence on the sex of offspring. Records of 1,801 births are tabulated 

 with respect to the number of services required before pregnancy ensued. I^oss 

 than 2 per cent of the conceptions took place after four or more servi 



A comparison of concentrates for fattening- steers in the South. W. 1'. 

 Ward, S. S. Jekda.n, and B. K. Lloyd (U. .S*. Dept. Agr. fiul. 761 {1919), pp. 

 16). — Results of two years' steer feeding experiments in the COOperat tee 



(E. S. R., 40, p. 665) conducted by the Rureau of Animal Industry of the I . s. 

 Department of Agriculture and the Mississippi Station are presented. Tin 

 lots of 25 steers, grades of the various beef breeds, were fed each winter for 

 the purpose of studying the value of cottonseed products when fed &s sole 

 concentrates or combined with some form of grain corn. The roughagea the 

 first year were corn silage and cowpea bay; in the second year corn silage 



liiuiiie Sta. Due. Oiy lll»10), Pp. 10 lb. 



