Overview

Most farmers will encounter the term “nutrient unit” when they are planning to build or expand their livestock barn or manure storage facility.

Depending on the livestock or poultry numbers that are housed on the farm upon completion, you may be required to have an approved nutrient management strategy (NMS) prior to starting their project and possibly a nutrient management plan (NMP), under the Nutrient Management Act, 2002 (NMA) and Ontario Regulation 267/03.

This page explains the calculations used to determine the number of nutrient units on farms and provides some examples.

About nutrient units

The nutrient unit (NU) calculation allows for an “apples-to-apples” comparison of different livestock and poultry manures based on the nutrient values of their manure.

A nutrient unit is defined in Ontario Regulation 267/03 as “the amount of nutrients that give the fertilizer replacement value of the lower of 43 kilograms of nitrogen or 55 kilograms of phosphate as nutrient as established by reference to the Nutrient Management Protocol”.

The NU conversion factors for most livestock and poultry types are summarized in Table 1, column C, and are also found in 2023 Table 1 Nutrient Unit Livestock Information in the Nutrient Management Tables for Ontario Regulation 267/03, made under the Nutrient Management Act, 2002.

How to calculate NUs

To calculate the number of nutrient units associated with a given livestock or poultry, divide the number of that given animal type and subclass on the farm by the corresponding NU conversion factor in column C of Table 1. If the result is not a whole number, round up to the next whole number.

For example, a beef cattle farm with 10 backgrounders has the equivalent of 4 NU since 10 divided by 3 NU per beef backgrounder equals 3.33.

If there is more than one livestock and poultry type on the farm, calculate the NU for each type and subclass of livestock and sum the various NU values together to determine the total NU value for the farm.

If the total NU capacity for all livestock and poultry types on the farm is greater than 5 NU, then an approved NMS is required prior to building or expanding a livestock barn or manure storage facility. The strategy shows how the manure, runoff and other farm generated wash water will be properly managed. If the total number of NU is 300 or greater, then a NMP is also required. Additional information about nutrient management strategies is found in OMAFRA fact sheet, When Farms Require an NMS, NMP or NASM Plan.

Examples

The following are two scenarios showing NU calculations and the need for an NMS and in some cases an NMP.

Scenario 1

A farmer is planning to build a barn to house up to 50 adult alpacas on a property. The farmer is unsure whether this number of adult alpacas will require an NMS to obtain the building permit.

To calculate the nutrient units, look at Column A and B to find the corresponding livestock and subclass. In this example, Alpaca is the livestock type and the subclass is “Adult” including unweaned animals and replacements. Look across this row at the corresponding NU factor for this type of livestock and subclass in column C. It indicates that 8 alpaca (adults) is equivalent to one NU. To calculate the NU for 50 adult alpacas, divide by the NU factor from column C which is 8 adult alpacas per NU and the result for this farm is 6.25 NU, which means an approved NMS is required to obtain the building permit. A NMP is not usually required in this situation because the number of NU is less than 300 NU, unless there is a municipal well within 100 m of the property.

Scenario 2

A dairy farmer recently purchased additional milk quota to fill the existing free stall barn that was constructed in 2016. The current livestock numbers on the farm are 200 Holstein cows and the farmer is planning to increase the herd to 220 Holstein cows with the additional quota. How many NU does the farm have currently and how many NU will the farm have if the herd increases in size to 220 cows? The dairy heifers and calves are housed on a different property that is not included in this NU calculation

To calculate the nutrient units, look at Column A and B to find the corresponding livestock and subclass. In this example, “dairy” is the livestock type and the subclass is “large farm - adult”. Look across this row at the corresponding NU factor for this type of livestock and subclass in column C. It indicates that 0.7 Holstein cows (adults) is equivalent to one NU. To calculate the NU, 200 Holstein cows (current herd size) divided by the NU factor from column C (0.7/NU) is equal to 286 NU. With expansion of the herd to 220 cows, then 220 cows divided by 0.7 animals/NU = 314 NU and a NMP would be required. The farm operator was required to have an NMS since 2016 when the barn was built.

Alpaca

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
AlpacaAdults (includes unweaned animals and replacements)8412,400
AlpacaFeeders
23-48 kg (50-105 lb)
261317,800

Beef

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
BeefCow calf (includes calves to weaning)16300
BeefBackgrounders316900
BeefFeeders316900
BeefShort keep211600

Bison

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
BisonAdults (includes unweaned replacements)1.37390
BisonFeeders
170 - 477 kg (375 - 1050 lb)
4211,200

Chicken

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
ChickenBroiler breeder grower (females and males transferred out)300150190,000
ChickenBroiler breeder layer (females and males transferred in)10050130,000
ChickenBroilers – 8-week cycle3511756105,300
ChickenBroilers – 9-week cycle300150190,000
ChickenBroilers – 10-week cycle250125075,000
ChickenBroilers – 12-week cycle19999659,700
ChickenLayer pullets (day-olds)5002501150,000
ChickenLaying hens15075145,000

Chinchilla

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
ChinchillaBreeding females (including males/rep/market animals)320160196,000

Dairy

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
DairyCalves – small framed (Jersey)8.5432,550
DairyHeifers – small framed (Jersey)2.915870
DairyCows – small framed (Jersey)16300
DairyCalves – medium framed (Guersney)7362,100
DairyHeifers - medium framed (Guersney)2.413720
DairyCows - medium framed (Guersney).856255
DairyCalves – large framed (Holstein)6311,800
DairyHeifers – large framed (Holstein)211600
DairyCows – large framed (Holstein)0.74210

Deer/elk

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
Deer/elkElk adults (> 24 months includes unweaned offspring)211600
Deer/elkElk feeders
91-162 kg (225-400 lb)
6311,800
Deer/elkHybrid adults** (24 months and older)4211,200
Deer/elkElk/red deer hybrid feeders
65-155 kg (160-340 lb)
10513,000
Deer/elkFallow deer adults (> 24 months includes unweaned offspring)13663,900
Deer/elkFallow deer feeders231166,900
Deer/elkRed Deer adults (> 24 months includes unweaned offspring)7362,100
Deer/elkRed Deer feeders14714,200
Deer/elkWhite Tailed Deer adults (> 24 months includes unweaned offspring)11563,300
Deer/elkWhite Tailed Deer feeders211066,300

Ducks

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
DucksPeking10552631,500

Emu

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
EmuAdults (includes unweaned offspring)12613,600

Fox

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
FoxBreeding females (includes replacement and market animals and males)251267,500

Goats

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
GoatsDairy does8412,400
GoatsDairy kids321619,600
GoatsFeeder kids
(>20 kg)
321619,600
GoatsMature meat goats8412,400

Horses

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
HorsesSmall framed211600
HorsesMedium framed16300
HorsesLarge framed0.74210

Llama

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
LlamaAdults (includes unweaned animals and replacements)5261,500
LlamaFeeders
45-86 kg (100-190 lb)
16814,800

Mink

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
MinkBreeding females (includes replacement and market animals and males)603011,800

Ostrich

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
OstrichAdults (includes offspring to market size)4211,200

Rabbit

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
RabbitBreeding does (includes bucks, replacements and market animals)4020112,000

Rhea

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
RheaBreeding adults (includes replacements and market birds)13663,900

Sheep

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
SheepDairy ewes and rams (includes unweaned offspring and replacements)6311,800
SheepDairy and feeder lambs201016,000
SheepMeat ewes and rams8412,400

Swine

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
SwineFeeders5.25271,575
SwineGilts5261,500
SwineSows (dry) and boars – non-SEW)3.5181,050
SwineSows (dry) and boars – SEW3.3317990
SwineSows with litters – non-SEW)3.5181,050
SwineSows with litters – SEW3.3317990
SwineWeaners201016,000

Turkey

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
TurkeyBreeder toms4522613,500
TurkeyBroilers
(less than 6.2 kg)
13366639,900
TurkeyHens
(6.2 to 10.8 kgs)
11055133,000
TurkeyToms
(greater than 10.8 kg)
7537622,500
TurkeyTurkey breeder layer6733620,100
TurkeyTurkey pullet
(0-6 week)
267133680,100

Veal

Column AColumn BColumn CColumn DColumn E
Livestock/poultry typeSubclassNumber of animals per NUNumber of animals required to be greater than 5 NUNumber of animals required to be equivalent to 300 NU
VealGrain fed6311,800
VealMilk fed6311,800

Disclaimer

The information in this document is provided for informational purposes only and should not be relied upon to determine legal obligations. To determine your legal obligations, consult the relevant law. If legal advice is required, consult a lawyer. In the event of a conflict between the information in this fact sheet and any applicable law, the law prevails.