Livestock genetic improvement is all about increasing the proportion of desired genes in the animals that breeders have on their farms. Even though this process has been occurring since animals were domesticated, it has only been documented over the past couple of centuries. With the vast majority of the improvement in yield occurring in the past seventy years.
The challenge that today’s breeders must address is how they will choose to further eliminate the unwanted and increase the proportion of desired genes in our milk producing animals. This applies to all species – bovine, buffalo, goats, sheep and yes even yaks, reindeer, and camels. Today few of us think of breeding dairy animals that are specific to their environment.
Dairy cattle breeding has gone through many stages to arrive at where we are at today with top cows that can produce over 2,200 pounds (1,000 kgs) of total fat and protein in a single lactation or have near perfect conformation.
The Bullvine looks both back and ahead at selection tools.
Advancements Made In Selection
Natural selection was a start but only a small start. Since then breeders had worked to develop animals and breeds using such tools as measuring performance, selecting sons and daughters from top cows, culling bottom enders, buying the best herd sire available, inbreeding followed by outcrossing, linebreeding and sharing elite bulls amongst an ownership group. With all of these breeders used what their eyes told them or the actual measured performance. (Read more: 6 Steps to Understanding & Managing Inbreeding in Your Herd, The Truth about Inbreeding and Stop Talking About Inbreeding…)
Significant genetic gains have occurred since WW II when breeders joined forces to jointly work to goals and geneticists analyzed the data to determine which animals had the best genetic make-up. The sampling of young sires from elite parents moved the dairy cattle breeding industry far along the journey to having cattle capable of producing over three times their previous yields. Recently an American cow is credited with 74,650 lbs of milk, 2,126 lbs of fat and 2,142 lbs of protein in 365 days. That’s almost 205 lbs (93 kgs) of milk per day for an entire year. And it seems almost every month now that we hear about cows scoring EX95 to EX97 in numerous breeds and countries.
Cloning was a tool tried, but the cost and the fact that an animal was replicated but not improved left it in the tried but of no use garbage bin. On the other side, there is sorting of semen by sex which now is nearing perfection for producing the sex of calf desired and matching unsexed semen for the ability to obtain a pregnancy.
The opportunity for improving the genetic ability of dairy cattle took a significant step forward in 2008 when genomic facts were added to the genetic evaluation process. The animal genomic information was added to the pedigree, classification and milk records resulting in genetic indexes with 60-70% accuracy where they formerly were 30-35%. Not since the change from only using visual observation to using parent, classification and milk records as the basis for decision had the accuracy of predicting genetic merit doubled.
Will Improvement Continue?
Where will the process of changing animals all end? Well, it won’t end.
The race to having a higher and higher proportion of animals with the genetic makeup that will maximize profit in tomorrow’s world will continue.
What Tools Are On The Horizon?
Already here is crossbreeding. Many breeders have been experimenting with taking genetics from top animals in pure breeds and crossing breeds. From a Holstein base, which is the case in most countries, numerous other dairy breeds are being used on a rotational or backcross basis to improve animals especially for health, fertility, longevity and other management traits. Without effective alternatives for selection from within breeds, crossbreeding schemes are likely to become more prevalent as a way to lessen the need for individual animal care, minimizing some of the added costs associated with high production and having animals that will perform in more rugged or extreme environments.
For some dairy farmers a new breed may be the answer. In New Zealand the Kiwi Breed (a combination of Holstein and Jersey) now makes up 50+% of the dairy cow population. It could be that Kiwi or some other composite breeds may come into popular support in other countries. Could it even be that in some regions of the world there is a return to dual purpose animals, breed for both milk and meat? (Read more: Holstein vs. Jersey: Which Breed Is More Profitable?)
Gene editing as a means of changing the genetic makeup of living beings is in the popular press at this time. The February 2nd National Post described gene editing as “… using tools to precisely edit genes inside living cells”. The National Post article added “There are a few methods but the technique known as CRISPR-Cas9 is a relatively fast, cheap and simple method that many researchers are keen to try”. On the human side the possibility for ‘genetic’ cures to miscarriages, infertility, HIV, MS, sickle cell disease and many others are a great hope. On the animal side fixing the problems by gene editing at the embryo stage sounds interesting at this moment.
Breeders and breeds need to be prepared for gene editing, perhaps as early as the next decade. For breed loyalists concerned about breed purity, it could be that the edited genes could come from selecting the ‘good’ genes from within a breed. I have had breeders, mainly in topical countries, wonder if the high milk solids percentages and heat resistance of the water buffalo could be added to our dairy cows. At this time there is are only questions and speculation. However progressive breeders always have and always will look to new techniques, as they come along, to make sure our dairy animals have the best genes possible.
What Cows Could Be On The Horizon?
Do we actually know what our dairy animals will be in the future? In fact, … NO!
But we can speculate. The Bullvine has produced many articles on what the dairy cow will be in the future. (Read more: She Ain’t Pretty – She Just Milks That Way!)
The Bullvine Bottom Line
Improving the genetics of dairy cattle will not go away or stop. The dairy cattle breeding industry needs to be open minded when it comes to the tools and techniques that will be used to make the cows of the future.