Sperm sorting in cattle
Hi all,
Our organisation is planning on doing work related to introducing sex-sorted semen in dairy industries in our country. The rationale behind wanting to do this is that in India, the male calves are abandoned and they typically die in ~2 years because they are either abandoned or sent for slaughter. So, by encouraging dairy farmers to use the sex-sorted semen, we would be able to save the male calves that would have been born, if not for the process of sperm sorting.
But on the other hand, 50% of male calves would now be replaced by female calves in addition to the already present 50%. The female calves usually have a lifetime of 8-10 years in Indian dairy farms after which they are either abandoned or sent for slaughter. This way, we are doubling the years of suffering for female calves while reducing the suffering of male calves which is one-fourth or one-fifth the suffering experienced by female calves.
Our conclusion is that this only serves an economic purpose and it won’t serve as a means of animal protection considering the increased number of years of suffering.
I would really appreciate it if I can get more perspectives on this.
Thanks,
Koushik
The total number of cows probably stays about the same, because if they had space to raise more cows they would have just done that—I don’t think that availability of semen is the main limiting factor. So the amount of suffering averted by this intervention can be found by comparing the suffering per cow per year in either cases.
Model a cow as having two kids of experiences: normal farm life where it experiences some amount of suffering x in a year, and slaughter where it experiences some amount of suffering y all at once.
In equilibrium, the population of cows is 5⁄6 female and 1⁄6 male. A female cow can, in the next year, expect to suffer an amount (x+y/10), and a male cow can expect to suffer an amount (x+y/2). So a randomly chosen cow suffers (x+y/6).
If male cows are no longer created, this changes to just the amount for female cows, (x+y/10).
So the first-order effect of the intervention is to reduce the suffering per cow per year by the difference between these two, y/15; i.e. averting an amount of pain equal to 1⁄15 of that of being slaughtered per cow per year.
Yes, the first-order effect makes sense. I am worried about the second-order effects.
Assuming that a cow is kept alive usually for 6 calvings, the cow would have produced 3 male and 3 female calves. If sex-sorted semen is used, the cow will now produce 6 female calves, i.e. (10x + y quantum of suffering units)*6 per cow per 10 years that is inseminated with sex-sorted semen.
The ripple effects of that would only produce more and more suffering (at an exponential scale), assuming that all of the female calves that are born via sex-sorted semen will again be inseminated with sex-sorted semen.
Also, can you please clarify your calculation wherein you arrive at y/15.
If I were you, I would try to somehow talk to the kind of farmers you would target, and ask if they would grow more cows if all calves were born female, preferably without making it clear why you are asking. I think that no amount of armchair theorizing can substitute that. You might find out about other indirect effects this way as well.
The practice might be different in different countries, but in many countries (I know the most about NZ) dairy cows are impregnated every year to keep their milk supply at a high level. The dairy cows are slaughtered after about 4 years, so there are far more calves born than can be used by the industry. This means that a decent proportion of the female calves are slaughtered alongside their brothers at a few days old so sex selection of sperm won’t change the number of unwanted calves. If there was a way to induce lactation without pregnancy that would make sex selection very useful.