1. CONCEPT OF LIVESTOCK UNITS
A livestock unit is a convenient unit for calculating all the animals in a herd. It is based on the
live weight of a mature cow of the dairy or beef type.
The livestock unit figure can then be used to estimate livestock roughage feed requirements over
a certain period of time. Hence it is useful in establishing roughage budgets and ensuring that
animals have enough feed throughout the year, even when there is drought.
Carrying capacity and stocking rate are two terms that confuse many.
Carrying capacity refers to the amount of forage Dry Matter that a certain unit of land to support
a certain number of animals per year or season for example 2,000kg/acre.
Stocking rate is a term referring to animal numbers in relation to carrying capacity of a unit area
of land or pasture (acres, Ha)
The concept is a follows
A stock unit represents one mature cow in dairy or beef enterprise which is used as the unit of
reference with respect to feeding. The unit depends on the breed and average live weight of the
mature breeding cow.
1. 1 Dairy cow of 400-500kg = 1.0 L. U
2. 1 Bull, Steer or Heifer >2years = 0.8 L.U
3. 1 Bull, Heifer or Calf < 2years = 0.5 L.U
4. 6 Sheep and Goats = 1.0 L.U
5. 3 Pigs = 1.0 L.U
6. 200 Chickens = 1.0 L.U
Total in farm = * L.U
The DM intake is based on the average cow’s body weight, for example, if 400kg cow, then
DM/L.U = 400 ×
3
100
= 12𝑘𝑔 hence 1 L.U will be supported by 12 KG DM/day
Example 1
Suppose one acre of pasture in Kitale is estimated to produce 9000kg DM per year. What is the
carrying capacity for a farmer whose livestock unit is based on a 500kg cow?
Solution
Carrying capacity =
9000
500×
3
100
×365 𝑑𝑎𝑦𝑠
=
9000
5475
= 1.64 𝐿. 𝑈/Acre/Year
Or the ideal stocking rate =
9000
15×365
= 1.64 L.U/Acre/Year
2. Hence the stocking rate and carrying capacity are essentially the same figure under ideal
conditions. However in practical application they can differ as when a farmer overstocks or
understocks a pasture.
Example 2
A farmer has a herd of 5 mature cows (average 400kg), 2 heifers of <2years, 12 goats, 9 sheep
and 300 chickens all under grazing. This farmer has 5 acres of pasture estimated to produce 7
tons DM/acre/year.
Calculate the following:
a) The total number of Livestock units
b) The total DM yield of pasture
c) The carrying capacity of the land or pasture
d) The stocking rate the farmer is using
e) Draw a conclusion and advice the farmer
Calculations
Total L.U = (5 × 1) + (2 × 5) + (12 ÷ 6) + (9 ÷ 6) + (300 ÷ 200) = 11 𝐿. 𝑈
Total DM yield = 5 × 7000 = 35,000𝑘𝑔 𝑜𝑟 35 𝑡𝑜𝑛𝑠
Carrying capacity/acre =
7000𝑘𝑔 𝐷𝑀
12×365
=
7000
4380
=1.6 L.U/Acre/Year
Stocking rate =
11 𝐿.𝑈
5 𝑎𝑐𝑟𝑒𝑠
=2.2 L.U/Acre/Year
Conclusion: since stocking rate of 2.2 L.U > carrying capacity of 1.6 L.U, the farmer should
reduce the stock or add more pasture.
Exercise
A farmer has 5 mature dairy cows of 450kg live weight, 8 heifers <2years, 18 goats, 8 sheep, 6
pigs and 300 chicken. Calculate the number of Livestock Units in the farm. How much forage
DM do they require per day? Base it on the requirement of one adult cow.
Kamadi Victor Bill- B.Sc. Animal Science
Project Officer-Food Security & Livelihoods, World Vision Kenya
Phone No. 0724025581, 0787681861
Email: kamadibill@yahoo.com, Victor-kamadi@wvi.org
Skype: bill.Kamadi