Produce of Calves by a Herd of Cows. 



113 



addition to other objections personal to myself which I should have 

 to making use of them, I conceive they would have so great a tend- 

 ency to make a cow slip her calf, that I should be very sorry to 

 allow them to be employed with any cow of mine which I valued. 



The result^ therefore, of my experience is, that no man can be 

 certain that a cow is in calf until he can feel the calf by what is 

 called punching the cow in her flank, an operation which is per- 

 fectly safe unless performed with most extraordinary and unne- 

 cessary violence. But as this cannot be done until the cow has 

 been pregnant at least six months, and in cows in good condition 

 sometimes till much later, the value of this mode of ascertaining 

 the pregnancy of a cow to breeders of cattle or purchasers at sales 

 is not very great. 



Although I thus failed in effecting the object which I had in 

 view when I commenced the series of observations which I am 

 about to state, they have led to results which I find very useful. 

 The mode I adopted was this : I noted each cow in succession 

 who had not returned to the bull at the end of six weeks, and 

 Avhen 50 were so noted I commenced a fresh series. I then noted 

 how many of each 50 went 7, 8, 9 weeks, and so on to 2 1 weeks, 

 before they returned to the bull, and how many proved in calf, 

 together with the number of live calves which they produced. I 

 have now the results of 8 of these series, or of 400 cows, who have 

 gone 6 weeks before returning to the bull. I here insert the 

 different series, together with the sum total of their results : — 



6 



7 



s 



9 



10 



11 



12 



13 



14 



15 



16 



.7 



18 



21 





Calves. 



50 



45 



41 



39 



38 



37 



34 



33 



32 



32 



30 



29 



29 



28 



26 



26 



50 



44 



39 



35 



33 



32 



30 



28 



27 



27 



27 



26 



26 



26 



25 



23 



50 



41 



38 



36 



31 



31 



30 



29 



28 



27 



27 



27 



27 



26 



23 



17 



50 



45 



41 



36 



34 



31 



30 



27 



26 



26 



26 



26 



26 



24 



20 



16 



50 



47 



44 



43 



43 



43 



42 



40 



39 



39 



37 



36 



36 



35 



33 



31 



50 



45 



42 



36 



35 



34 



32 



30 



26 



24 



24 



24 



24 



23 



20 



IS 



50 



42 



41 



39 



37 



36 



35 



32 



31 



30 



30 



30 



30 



28 



26 



24 



50 



48 



47 



41 



41 



39 



39 



36 



36 



36 



34 



34 



34 



31 



29 



26 



400 j357 



i 



333 



305 



292 283 



27" 



255 



245 



- 



241 



235 



232 



232 



221 



202 



181 



It will be seen from this Table that the variations between the 

 different series are not very great, and that a man applying a 

 calculation founded upon the sum totals of them to any one would 

 not err more than must always be the case in any calculation 

 founded upon probabilities. Having found this to be so w^ith 

 respect to cows who had not returned to the bull for 6 weeks, I 

 applied the same principle to all the cows who were bulled, in 

 order to ascertain what was the probability of each cow bulled 



VOL. II. I 



