Dairy Australia - Dairy information for Australian Dairy Farmers and the industry

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Primary content

Introduction

This app will help you check whether your heifers are likely to reach their target weights.

The Estimate Extra Production tool lets you estimate the extra production that might be achieved if heifers reach a target of 85% of the production of the mature cows.

The Estimate Reduced Culling tool helps you see the impact of heifers being lost early from the herd.

The weight calculator tool will let you enter the current weight and the target weight of your heifers and will help calculate the growth rate required to achieve your target weight.

The Growth Calculator tool will allow you to enter the diet you are feeding, and to see whether this diet is likely to achieve the growth rates you need

Heifer Growth Rate Calculator

This calculator is designed to work out what growth rate your heifers will need to achieve to meet their target.

Calving start date:
Calving weight:
Date:
Weight:
Growth rate required: kg/day

As a rule of thumb, growth rates of 0.6-0.8 kg/day are fairly easy to achieve from pasture alone.

Growth rates above 0.8 kg/day may require supplementary feed.

You can use the Diet Calculator tool to see if your current diet is likely to pose a risk.

Consult a nutritionist if your diet poses a risk of under-target heifers.

Heifer Target Weight Chart Tool

Calving start date:
Calving weight:
Required Growth Rate: kg/day
Date Target (kg) Age (Months)
24

(The graph below may not display on an Ipad)

Heifer Diet Calculator

This calculator is designed to work out what growth rate your heifers are likely to achieve on their current diet.

Step 1. Current targets:

Current heifer weight:
Growth rate required:

Step 2. Requirements

Your heifers require:
Energy for Maintenance: MJ
Energy for Growth: MJ
Total Energy: MJ
Protein % required: %

Step 3. Pasture availability

What sort of pasture is available?

ME Protein NDF

Step 4. What supplementary feed are you giving them?

Feed (in DRY MATTER) Kg DM/Day MJ/Kg Protein % % NDF
Barley 12.4 11.3 20
Canola  12.5 39 20
Hay - average 8.5 10 60
Hay - good 10 14 50
Hay - vetch 10.5 18 45
Lupins 13 31.3 20
Palm Kernel Extract 11 17 57
Silage  10.5 15 50
Wheat 13.3 10.5 10
Summary:

Step 5. Analysis

Total Diet Protein %:
Max Pasture intake (kg): 

Assuming the grass above and that heifers are eating as much as they can we can calculate the expected growth rate:

Total Diet Protein % :
Dietry ME from Pasture
Dietary ME from Supplements:
Total dietry ME  (MJ):
Expected growth rate (kg/day): 

(Note - these calculations are based on rules of thumb only. You should seek professional advice before acting on these calculations!)

I Herd Test

This tool estimates the increased production that might be achieved if heifers are "On Target"…

Average Lactation Production (cows): Litres
Average Lactation Production (Heifers):  Litres
Your heifers are producing this %:

If they produced 85% of the mature cows you could be producing this many more litres per heifer:

(you could produce more milk, or the same milk with less cows)

Estimate reduced culling

Herd Structure:

How many first calvers do you have ? cows
How many second calvers do you have ? cows
The ratio is 
If you reached a target of 85%, No.  of extra second calvers you might have:

Typical feed values

Feed ME Protein NDF
MJ/kg DM % %
No or very limited pasture 0 0 0
Pasture - Autumn 10 14 50
Pasture - Irrigated 11.5 22 40
Pasture - late spring 11 18 45
Pasture - lush spring 12 25 35
Pasture - Summer 9.5 12 55
Pasture - Winter 11.5 25 35
Barley 12.4 11.3 20
Canola  12.5 39 20
Hay - average 8.5 10 60
Hay - good 10 14 50
Hay - vetch 10.5 18 45
Lupins 13 31.3 20
Silage  10.5 15 50
Wheat 13.3 10.5 10

Typical heifer requirements

BW Maintenance Growth Protein 
Kg mj/d mj/kg %
25 6 10.4 17
50 10 13.2 17
75 14 14.6 17
100 17 19.8 17
125 20 21.5 17
150 24 23.3 17
175 27 25.0 17
200 29 26.7 17
225 32 28.4 17
250 35 30.0 15
275 38 31.6 15
300 40 33.3 15
325 43 34.8 15
350 45 36.4 14
375 47 37.9 14
400 49 39.5 14
425 52 40.9 14
450 54 42.3 14
475 56 43.8 14
500 58 45.2 14

** These are rules of thumb only.

Temperature, exercise and genetics and other factors will affect requirements

(Adapted from Holmes CW, Wilson GF (1987) Milk Production from Pasture)

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