It is important that the collection and preparation of the dung sample for faecal NIRS analysis is done properly. This ensures that the sample is acceptable upon arrival, that there is no mould or any contamination of the sample that would affect the quality of the diet quality analysis.
The submission form should be filled out as comprehensively as possible to ensure a more comprehensive interpretation and report.

How to collect a dung sample

1. Samples should be collected from cowpats of 10 to 20 animals. Alternatively, if cattle are yarded, the samples can be collected directly from the animal.
2. Collect 1 tablespoon of dung from each cowpat/animal. Ensure that the amount collected from each animal is consistent.
3. Place all of the samples into one container. Mix the bulk sample thoroughly.
4. Keep the sample cool until it is ready to be dried.

IMPORTANT:
Ensure that the dung samples are free of soil, mucus and dung beetles. Also ensure that the samples are collected from cowpats that are only 1-2 hours old. Do not collect samples from cowpats where there has been evidence of dung beetle activity. Samples with any contamination will affect the accuracy of the diet quality results.

Drying the sample

There are two methods for drying samples. The most commonly used method is sun-drying. Alternatively, samples can be oven-dried, however, it is absolutely critical that they are oven-dried at a temperature of no greater than 65°C. Most conventional ovens are incapable of drying at this low temperature, so sun-drying is the most commonly used option. If a faecal sample is dried at a higher oven temperature, the sample will be rendered useless and cannot be analysed by the lab.

If a sample has been oven-dried, this must be noted on the submission form that is sent with the sample. This is because the digestibility predictions for oven-dried samples are 1.5% higher on average, than for sun-dried samples.

1. The bulk sample that is collected should be spread out to 1 cm thickness on a sheet of aluminum foil or on a baking tray. Spread the sample out as one pancake so that it can be turned over easily halfway through drying.
2. If there is more than one sample to be dried, label each sample to maintain their identity.
3. Place the sample in a high spot, such as a rainwater tank or roof, so that they are out of reach of dogs, dung beetles and soil contamination from wind. The sample may also be covered over with mesh or gauze.
4. Dry the sample for approximately half a day, then turn it over to allow the other side to dry.
5. Once the sample is dry, cool it thoroughly. This will prevent the sample from “sweating” in the sample container and subsequent formation of mould, which will spoil the sample.
6. Only one sample container should be filled per sample group/paddock.

Labelling the sample container

1. Property
2. Paddock name
3. Date of sampling
4. Class of stock

What to include in the postpak

1. Thoroughly dried sample in either a ziplock bag or sample jar that is clearly identified with property name, paddock name, date of sample. The sample bag or jar must be properly sealed to prevent spillage.
2. A hard copy of the submission form – for each sample that is sent. An electronic copy of the submission form for each sample sent must also be sent to the lab, to ensure that the information for the sample is entered onto the system. This will expedite the time it takes for the sample to be analysed once it arrives at the lab.

Other information

1. Although these instructions make reference to cattle, many producers have also sent in samples from sheep. The original calibration equations were based on pen studies with cattle so the accuracy of the diet quality results for sheep cannot be guaranteed. However, this is still the best method available for analyzing diet quality in sheep.
2. Expect a turnaround time for results of 10 working days from when they are posted.
3. The quality of the interpretation and report is vastly improved by providing background information on the submission form.
4. Samples should not be collected immediately following major rainfall events because the pasture is growing rapidly and so diet quality is also changing rapidly. Samples should be collected at least two weeks after a rainfall event. After small falls of rain, a sample can be collected a week later.

Further information

For further information contact:
Mobile: 0431 411 647
E-mail: admin@gcology.com.au