34 



BLTLLETIX 1090, U. S. DEPARTIMEXT OF AGEICULTURE. 



Table 11. — The average birth weiqht 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.] 





Size of litter. 









Size of litter. 





Year. 







In- 

 dex. 



Year. 





In- 

























dex. 





1 



2 



3 



4 







6 







1 



2 



3 



4 







6 





1906 



104.5 



110.7 



81.1 



70.6 



i 



90.2 



1914 



109.9 



94.2 



82.0 



71.9 



67.4 



61.6 



86.4 



1907 



101.8 



91.8 



78. 8 i 69. 



64.3 



.58.5 



8.3.0 



1915 



105. 3 



89.3 



76.0 



67.1 



61.2 



60.5 



81.1 



190S 



112. 2 



92.9 



82.2 



75.1 



67.2 



62.9 



87.0 



1916 



99.4 



81.5 



68.2 



59.6 



58.3 



47.8 



73.6 



1909 



107. 5 



91.3 



80.6 



72.6 



68.0 



58.9 



84.9 



1917 



98.3 



77.7 



67.0 



56.1 



59.5 





71.2 



1910 



113.0 



97.4 



Ki.l 



74.2 



67.5 



63.7 



88.6 



1918 



99.5 



81.4 



70.3 



61.9 



79.5 





74.9 



1911 



107.1 



93.2 



79.7 



71.9 



66.8 



.58.3 



85.0 



1919 



108.3 



87.9 



74.7 



66.1 



60.9 





80.3 



1912 



108.1 



94.2 



81.0 



71.7 



67.0 



64.1 



85.8 



1920 



105.4 



87.4 



73.5 



66.4 



60.7 



56.5 



79.4 



1913 



109.6 



92.4 



81.2 



70.8 



65.9 



60.9 



85.3 



















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- 









i 















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 !l24. 5 



111.3 



161.0 



1907 



18.5.4 



166.7 



152. 3 1130. 2 



116.2 



147.0 



155. 6 



1915 |163.5 152.9 



126.5 



102. 3 ;lll. 1 



137.0 



133.3 



1908 



197.3 



165. 4 



151. 9 1143. 8 



127. 1 '113. 8 



158. 9 1 



1916 1143. 2 114. 7 



• 89.9 



77. 6 1 76. 7 





100.2 



1909 



179.5 



170.6 



1.53.5 il42. 8 140.0 ll2L 8 



159.1 



1917 141.1 123.8 



110.8 



94 3 140. 





1144 



1910 



199.2 



1S6.9 



165.4 1149.9 ,1.34 9 '129.5 



172.1 



1918 139.5 134.3 



124.4 



121.2 130.0 





128.2 



1911 



16S. 5 



157. 1 



133.0 il2.8.3 1121.6 112.7 



142.8 



1919 164.8 143.6 



126. 115. 4 112. 9 





133.0 



1912 



175. 8 



166.7 



145.5 124.1 il2.5. 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. 



1 J 1 1 



15L8 1 



1 





1 











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.] 





Size of litter. 







Size of litter. 





Year. 





In- 

 dex. 



Year. 





In- 



























dex. 





1 



2 



3 



4 



o 



6 







1 



2 



3 



4 



5 



6 





1906 . 329. 5 



272.0 



233.7 



173.9 

 199.2 







242.8 

 238. 6 



1914. . 

 1915.. 



300.9 



268.8 



268.7 



237.6 208.3 



191.9 il72.9 

 172.3 197.5 



247.4 



1907.. 287.2 



258. 5 |231. 1 



180.5 



205.5 



242.2 1202.5 :169.4 



214 4 



1908.. 309.5 



258. 3 1234 1 



218.9 



194 3 176.7 



245.9 



1916.. 1242. 6 



196.2 ;158. 1 137.2 



1341 



173.8 



1909.. 287.0 



261. 9 !234 1 



215.4 



208.0 180.7 



244 



1917..|239.4 



201. 5 177. 8 150. 4 



199.5 1 



185.6 



1910.. 312.2 284 3 !248.5 



2241 



202.4 193.2 



260.7 



1918.. 239.0 



215. 7 194 7 183. 1 



209.5 1 



203.1 



1911... 275. 9 2.50.3 ;212.7 



200.2 



188.4 171.0 



227.8 



1919. . 273. 1 



231. 5 200. 7 181. 5 



173.8 ' 



213.3 



1912.. 1283.9 260.9 226.5 



195.8 1192.1 17L1 



236.4 



1 1920. . 268. 8 



243.3 207.1 190.9 



190.0 185.5 



220.9 



1913..;29L7 248.7 1229. 3 



208.0 1202.5 225.9 



237.1 



1 



: 



! 





Table 14. — Data on the fertility of the control stock (B) by years, 1911 to 1920. 



Year. 



Size of litter. 



Mat- 

 ings. 



Num- 

 ber of 

 Utters. 



Num- 

 ber of 

 young. 



Average 



size 



of 



litter. 



Litters 

 per 

 year. 



Young 



1 



2 



3 



4 



5 



6 



7 



8 



9 



year. 



1911.. 

 1912.. 

 1913. . 

 1914. . 

 1915. . 

 1916. . 

 1917.. 

 1918. . 

 1919. . 

 1920.. 



6 

 11 

 16 

 17 

 19 

 20 

 22 

 28 

 11 

 23 



20 

 31 

 37 

 51 

 31 

 56 

 51 

 40 

 41 

 35 



41 

 35 

 66 

 55 

 40 

 64 

 59 

 43 

 46 

 50 



16 

 16 

 17 

 42 

 31 

 21 

 24 

 17 

 16 

 34 



9 

 7 

 9 

 18 

 13 

 7 

 2 

 1 

 11 

 11 



2 

 6 

 5 



8 

 2 

 2 

 



1 

 4 

 4 





 2 



1 

 1 

 

 



1 





 



1 



1 

 

 

 

 

 

 

 

 

 







1 





 

 

 

 

 

 

 



2.3.0 

 26.9 

 40.7 

 53.0 

 42.5 

 48.0 

 41.8 

 35.6 

 34 3 

 34.7 



95 

 109 

 151 

 192 

 136 

 170 

 1.59 

 130 

 129 

 158 



298 

 336 

 438 

 597 

 402 

 455 

 414 

 316 

 374 

 465 



3.14 

 3.08 

 2.90 

 3.11 

 2.96 

 2.68 

 2.60 

 2.43 

 2.90 

 2.94 



4.13 

 4.05 

 3.71 

 3.62 

 3.21 

 3.54 

 3.81 

 3.65 

 3.76 

 4. 55 



12.96 

 12.49 

 10.76 

 11.26 

 9.46 

 9.48 

 9.90 

 8.88 

 10.90 

 13.44 



