80 Breeding f 07' Increase of Milk in Dairy Cattle 



the dam and 20°/„ which showed a decrease in the yield of the cow when 

 compared with her dam. 



In Table II are given the results : (a) of mixed inbreeding to both 

 male and female relationships, the male being the nearer and therefore, 

 presumably, the stronger. It will be noted that though there are only 

 10 cases the percentages showing increase of milk and decrease of milk 

 are respectively 80 "/^ and 20°/^, (6) mixed inbreeding with the female 

 relationship the nearer, these are all decreases. 



Table III gives out- or chance-breeding experiments and its results. 

 There are 31 cases of these — only four were increases, i.e. 87 °/^ showed 

 a decrease in milk yield and 13°/^ an increase. 



The pedigrees attached explain what is meant by related breeding. 

 It may be described as " the mating of a bull with a cow who is so 

 related to him that their first common ancestor is a bull " or in other 

 words, one or more bulls must be repeated in both the sire and dam's 

 pedigrees. These, then, become " links," i.e. linking bull or bulls and 

 make a malely related breeding. 



A femalely related breeding is described in the same terms substi- 

 tuting cow for bull. 



Full relationships are made when the same bull and cow give rise to 

 the animals " through" whom the link is carried on. It is interesting to 

 note that breeding to full relationships appears to produce a maintenance 

 of the dam's record in her female calves. 



In Pedigree IV Gort Sheen </ is mated to Mona % in both pedigree 

 of sire and dam and the full brother and sister Vaddy Sheen cT and 

 Glenelly $ ultimately make a " full " first cousin once removed relation 

 between their descendants Burntollet II (/ and Glenelly II $ . 



Pedigree V illustrates a " nearly full " relationship. 



H, B, and 8 is an abbreviation for half brother and sister. 

 Avunc. is an abbreviation for Avuncular relationship, i.e. Uncle 



and niece or Aunt and nephew. 

 1st once signifies first cousin once removed and so on. 



The third lactation is taken as the standard year and most cows do 

 reach their full development then. 



In Table IV sundry tables are given : 



(1) The annual average of butterfat for the whole herd showing the 

 gradual rise as the herd became more and more " bred." 



(2) A table showing the results of classifying the heifer by the rise 

 of the yield in milk in comparison with their dams' records in quantity 

 and quality. 



