Data plays a critical role in the management of my flock.
Decisions are made based on data, not emotion.
I firmly believe that the cornerstone of any herd enterprise is its female base.
Assembling a winning team of ewes is every bit as challenging as putting
together a winning sports team. The key is to identify those
individuals who are "pulling the wagon" and those who are weighing it down.
There are numerous flock management programs available to manage flocks,
including Ewebyte, NSIP and others. None of these meet my need to
maximize the only parameter that I'm truly concerned with - profitability.
Starting in the fall of 2007, I have been developing
a selection methodology that
combines virtually every profit controlling parameter into single number -
what I call the Profitability Index (PI). Simply, the PI is the
amount of profit that the ewe is generating under given market conditions (I
currently use a 4 year average).
The index includes all variable costs (including labor), fixed costs, finish weight,
feed efficiency, prolificacy, heterosis and longevity.
The method not only helps me find those ewes that are
earning the most
money, but also attempts to project future performance based on to-date
performance and historical data for sheep of that type (breed / cross).
Further, the software decouples each characteristic so that complimentary matings can be identified.
Finally, the software models the price
of lamb, corn and other feedstuffs to assist in marketing and
The software is not commercially available, in part, because it is not
I use the NRC 2007 "Nutrient Requirements of Small Ruminants" to
rations for highly productive sheep for
gestation and lactation periods. The
goal is to provide high performance rations at the least cost.
The primary advantage is the elimination of all
commercial feeds. I only buy commodity feedstuffs, vitamins and
I monitor and project lamb and feed prices to find the marketing date
that produces the maximum profit. That may mean selling the lambs as
feeder lambs all the way up to the upper end of Yield Grade 3.
I measure the following data:
Prolificacy is measured by the number of lambs weaned per ewe
dry-lotted after breeding.
Ewe longevity is measured by the ewe's age.
Growth is measured by taking 3 weights of the lambs.
Generally, these are at weaning, around 100 days and right before
slaughter. The weights are then standardized to 60, 120 and 180
day values by curve fitting the 3 measurements to the Gompertz growth
function. The Gompertz growth function is a mathematical model for
growth. It accounts for the fact that a lamb's growth rate
continuously varies with time. This is particularly important
because growth starts to decline as they 'finish' or put on fat.
This method is more accurate and far less optimistic than the linear
methods used by virtually everyone else.
Ewe feed cost is computed from the ewe's mature weight
and production. Ewes
are weighed once a year and adjusted to Body Condition Score 3.
Feed efficiency is computed from the 60, 120 and 180 day weights
using a relationship between body weight and feed intake. In 2010, the
average predicted feed efficiency for a group of about 40 lambs was
within 2% of the actual feed efficiency I measured. In 2011, the
predicted value was within 1% of the actual value.
Labor. Prior to 2012,
labor costs evenly across the ewe flock. Starting in 2012, an
estimate of individual annual labor requirements is assigned to each
principle differentiator is the number of assisted births. The goal of the labor tracking
is to make sure that production levels are optimized with labor
requirements. Labor requirements have been used in
determining ewe lamb selections starting with the 2013 crop.
Results - Mature Ewes:
I began using the software in Spring 2008 to select
replacement ewe lambs, rams and culls. For the first two years, I did
not have a scale, so the growth data was estimated. Starting In 2010, precise growth data was added.
Starting in 2014, I purposely began
sacrificing production to reduce
costs - particularly labor. Specifically, ewes were no longer allowed to wean
quads, very problematic ewes were culled and lambing ease became a
selection criteria. While progress is not a straight line,
progress in reducing the number of assisted births is being made.
Production results for ewes born on my
farm are presented below. The finish weights are standardized to
Potential = Lambs Born x Finish
The 2017 crop was a bit of a disappointment. Production
decreased 5.5%. The main reason for the decline was an
increased number of single births. Several factors contributed
to this: very high temperatures during breeding season and a record
high age of mature ewes (averaging 4.2 years old). However,
there is another factor at play here. My records indicate that
the most profitable lambing percentage for my cost structure is
around 240%. Starting with the 2015 crop, I have not retained
the most prolific ewe lambs. The goal is maximum profit, not
- Ewe Lambs:
Potential = Lambs Born x Finish
In 2015 it became apparent that
my ewe lambs were becoming much too prolific. That year, I began
selecting less prolific ewe lambs and slowed their pre-breeding
development. Lambing rates were dramatically reduced. The
reduction in production was significant, but declined less than the
lambing rate. This is reflected in
the higher survival and growth rates of the lambs. I don't think I
have quite the right formula in place yet, but do feel things are
heading in a sustainable direction.