Profitable Lifetime Index: why you should use it?
PLI is now over 10 years old and during the last decade, it has developed into an index which is widely used and respected and has been clearly proven to relate to actual profitability on the farm.
Like all UK genetic indexes, it has been developed on the back of millions of British cow records, which have been used to identify the traits most strongly linked to overall profitability and to identify bulls which transmit these characteristics on to their daughters.
These traits are milk production, fertility, lifespan, udder conformation, cell counts and locomotion. They are each weighted according to their relative influence on lifetime profitability.
But not all of these traits were included in the original PLI, and as both knowledge and the ability to measure cows has improved, new traits have been added - and will continue to be added in the future.
Most farmers will not be surprised by the traits included and most would agree that whilst production is the number one earner, problems such as infertility, high cell counts and lameness are often the issues which interfere with a cow's ability to milk, and lie behind her departure from the herd. They would probably equally agree that herdlife itself - and the influence it has on replacement rates - has an important bearing on a arm's bottom line. The net result is that cows with a higher PLI will, on average, make more profits.
Of course, there will be exceptions to this rule, but there is compelling evidence to prove the profit potential of PLI from a variety of farm costings services.
In fact, work undertaken in 2011 by Promar, found each PLI point to be worth £4.21 in additional margin per cow per year - which is more than geneticists and breeding specialists predicted!
Translate this to a 100-cow herd, and a top herd, compared with an average PLI herd, can earn close to £25,000 extra margin per year through better genetics alone.