34 



BULLETIN 1090, U. S. DEPARTMENT OE AGRICULTURE. 



Table 11. — The average birth tueight in grams of young raised to 33 days. Inbred stock 



by years, 1906 to 1920. 

 [The average in litters of each size and the index, as in Table 7.] 



Year. 



Size of litter. 



In- 

 dex. 



Year. 



Size of litter. 



In- 



1 



2 



3 



4 



5 



6 



1 



2 



3 



4 



5 



6 



dex. 



1906 

 1907 

 1908 

 1909 

 1910 

 1911 

 1912 

 1913 



104.5 



101.8 

 112.2 

 107.5 

 113.0 

 107.4 

 108.1 

 109.6 



110.7 

 91.8 

 92.9 

 91.3 

 97.4 

 93.2 

 94.2 

 92.4 



81.1 

 78.8 

 82.2 

 80.6 

 83.1 

 79.7 

 81.0 

 81.2 



70.6 

 69.0 

 75.1 

 72.6 

 74.2 

 71.9 

 71.7 

 70.8 



*64.Y 

 67.2 

 68.0 

 67.5 

 66.8 

 67.0 

 65.9 



"58." 5' 

 62.9 

 58.9 

 63.7 

 58.3 

 64.1 

 60.9 



90.2 

 83.0 

 87.0 

 84.9 

 88.6 

 85.0 

 85.8 

 85.3 



1914 

 1915 

 1916 

 1917 

 1918 

 1919 

 1920 



109.9 

 105.3 

 99.4 

 98.3 

 99.5 

 108.3 

 105.4 



94.2 



89.3 

 81.5 

 77.7 

 81.4 

 87.9 

 87.4 



82.0 

 76.0 

 68.2 

 67.0 

 70.3 

 74.7 

 73.5 



71.9 

 67.1 

 59.6 

 56.1 

 61.9 

 66.1 

 66.4 



67.4 

 61.2 

 58.3 

 59.5 

 79.5 

 60.9 

 60.7 



61.6 

 60.5 

 47.8 



'56.* 5" 



86.4 

 81.1 

 73.6 

 71.2 

 74.9 

 80.3 

 79.4 



Table 12.— The average gain in grams between birth and 33 days. Inbred stock by years, 



1906 to 1920. 

 [The average in each size of litter and the index, as in Table 7.] 





Size of litter. 







Size of litter. 





Year. 





In- 

 dex. 



Year. 





In- 



























dex. 





1 



2 



3 



4 



5 



6 







1 



2 



3 



4 



5 



6 





1906 



225.0 



161.3 



152.6 



103.3 







152.6 



1914 



191.0 



174.5 



155.6 



136.4 



124.5 



111.3 



161.0 



1907 



185.4 



166.7 



152.3 



130.2 



116.2 



I47. 6 



155.6 



1915 



163. 5 152. 9 126. 5 



102.3 



111.1 



137.0 



133.3 



1908 



197.3 



165.4 



151.9 



143.8 



127.1 



113.8 



158.9 



1916 



143.2 [114.7 1 89.9 



77.6 



76.7 





100.2 



1909 



179.5 



170.6 



153.5 



142.8 



140.0 



121.8 



159.1 



1917 



141. 1 ,123. 8 |ll0. 8 



94.3 



140.0 





114.4 



1910 



199.2 



186.9 



165.4 



149.9 



134.9 



129.5 



172.1 



1918 



139.5 ! 134.3 1124.4 



121.2 



130.0 





128.2 



1911 



168.5 



157.1 



133.0 



128.3 



121.6 



112.7 



142.8 



1919 



164.8 143.6 126.0 



115.4 112.9 





133. 



1912 



175.8 



166.7 



145.5 



124.1 



125.1 



107.0 



150.6 



1920 



163.4 155.9 133.6 



124.5 129.3 



129.0 



141.5 



1913 



182.1 



156.3 



148.1 



137.2 



136.6 



165.0 



151.8 













Table 13. — The average weight in grams at 33 days. Inbred stock by years, 1906 to 



1920. 









[The average in each size of litter and the index, as in Table 7.] 









Year. 



Size of litter. 



In- 

 dex. 



Year. 



Size of litter. 



In- 



1 



2 



3 



4 



5 



6 



1 



2 



3 



4 



5 6 



dex. 



1906 



329.5 

 287.2 

 309.5 

 287.0 

 312.2 

 275.9 

 283.9 

 291.7 



272.0 



258.5 

 258.3 

 261.9 

 284.3 

 250.3 

 260.9 

 248.7 



233.7 

 231.1 

 234.1 

 234.1 

 248.5 

 212.7 

 226.5 

 229.3 



173.9 

 199.2 

 218.9 

 215.4 

 224.1 

 200.2 

 195.8 

 208.0 







242.8 

 238.6 

 245.9 

 244.0 

 260.7 

 227.8 

 236.4 

 237.1 



1914. . 

 1915.. 

 1916.. 

 1917.. 

 1918.. 

 1919.. 

 1920.. 



300.9 

 268.8 

 242.6 

 239.4 

 239.0 

 273.1 

 268.8 



268.7 

 242.2 

 196.2 

 201.5 

 215.7 

 231.5 

 243.3 



237.6 

 202.5 

 158.1 

 177.8 

 194.7 

 200.7 

 207.1 



208.3 

 169.4 

 137.2 

 150.4 

 183.1 

 181.5 

 190.9 



191.9 172.9 



247.4 



1907.. 

 1908.. 

 1909.. 

 1910.. 

 1911.. 

 1912.. 

 1913.. 



180.5 

 194.3 

 208.0 

 202.4 

 188.4 

 192.1 

 202.5 



205.5 

 176.7 

 180.7 

 193.2 

 171.0 

 171.1 

 225.9 



172.3 

 134.1 

 199.5 

 209.5 

 173.8 

 190.0 



197.5 

 185.' 5' 



214.4 

 173.8 

 185.6 

 203.1 

 213.3 

 220.9 



Table 14 



. — Data on the fertility ofth 



e control stock (B) by years, 1911 to 1920. 



Year. 









Size 



of litter. 









Mat- 



Num- 

 ber of 



Num- 

 ber of 



Average 



size 



of 



litter. 



Litters 

 per 



Young 























1 



2 



3 



4 



■5 



6 



7 



8 



9 





litters. 



young. 



year. 



year. 



1911.. 



6 



20 



41 



16 



9 



2 







1 







23.0 



95 



298 



3.14 



4.13 



12.96 



1912.. 



11 



31 



35 



16 



7 



6 



2 







1 



26.9 



109 



336 



3.08 



4.05 



12.49 



1913.. 



16 



37 



66 



17 



9 



5 



1 











40.7 



151 



438 



2.90 



3.71 



10.76 



1914.. 



17 



51 



55 



42 



18 



8 



1 











53.0 



192 



597 



3.11 



3.62 



11.26 



1915. . 



19 



31 



40 



31 



13 



2 















42.5 



136 



402 



2.96 



3.21 



9.46 



1916.. 



20 



56 



64 



21 



7 



2 















48.0 



170 



455 



2.68 



3.54 



9.48 



1917.. 



22 



51 



59 



24 



2 







1 











41.8 



159 



414 



2.60 



3.81 



9.90 



1918. . 



28 



40 



43 



17 



1 



1 















35.6 



130 



316 



2.43 



3.65 



8.88 



1919.. 



11 



41 



46 



16 



11 



4 















34.3 



129 



374 



2.90 



3.76 



10.90 



1920. . 



23 



35 



50 



34 



11 



4 



1 











34.7 



158 



465 



2.94 



4. 55 



13.44 



