The GREEN HORSE - sustainable horsekeeping

In the December/January 05/06 issue of The Green Horse you will find the following articles:

Talking Point and Information Exchange
Nature’s Free Labourers - the Dung Beetle and Earthworm by Sharon Roberts
Run Rabbit Run by Carol Willcocks
Weed Watch - Parthenium by Nicola Field
Silo Bags Solve Storage Crisis
Growing Equine Herbs- Chickweed by Fiona Adams
Grazing Management Systems Part 2 by Jane Myers
Garlic Overdose Research
Trees - An Asset or Potential Disaster? by Chris Ferreira and Tracey Bell

You can read the Grazing Management - Systems and Garlic Overdose Research articles below

Grazing Management ... Systems

photo and article by Jane Myers

The utilisation of grazing systems can maximise pasture production and extend the grazing season.

Above left: Horses cause just as much damage to the land during time spent loafing or sleeping in the paddock, as when grazing.
Above right: A good set of yards means the horses can be confined when grazing is limited.

As a horse owner there is a need to regard pasture in much the same way as a farmer would if the aim is to reduce feed bills, enhance the property and the wider environment, and reduce dust, mud and erosion.

Using grazing systems increases the productivity of the pasture and allows more flexibility in the number of horses that can be kept. With the exception of Set Stocking, the grazing systems outlined here are all variations on the same theme of restricting horses to one part of the property while the other parts are rested to allow recuperation. These systems can be used in conjunction with one another for good results. Aim to be flexible and be prepared to change systems to suit the current situation, for example, different strategies may be more suitable for use due to the seasonal variations in most parts of Australia.

When using these grazing systems a good set of yards is required so horses can be safely confined. Time spent grazing can then be decreased when pasture is not available and increased when it is. Supplementary feed is used to make up the shortfall in pasture and, as the pasture improves, the time spent grazing can be increased with less reliance on supplementary feed.

Set Stocking
Set stocking is the practise commonly used on horse properties whereby horses are allowed access to all of the land all of the time - either individually with one horse per paddock, or as a group where the horses have access to the whole property all of the time. This practise usually leads to unhealthy land and unhealthy horses as the land becomes degraded - gradually or quickly, depending on the land type. Set stocking is to be avoided as a management practise on all but very large properties with low stocking rates, and even in this situation, cross grazing can also be used to negate some of the effects of set stocking.

Rotational Grazing
Having several smaller paddocks rather than one large paddock allows the use of paddock rotation. In this system the horses are moved around the property as a herd. This improves pasture growth and parasite control and reduces land degradation. Using this method of management will help to prevent the under/over-grazing pattern present in so many horse paddocks.

Horses should be allowed to begin grazing a paddock when it has reached an average height of approximately 15 to 20 centimetres. When they have grazed the paddock to an average height of five to eight centimetres it is time to move them to another paddock. Any areas that have less than 70 percent ground cover or are bare, dusty or boggy should be temporarily fenced off with electric tape when the horses have access to that paddock.

When the animals are moved on, the now empty paddock can be harrowed to break up any manure piles, mowed to an even length and then rested and allowed to re-grow back to the 15 -20 cm height. At this point the horses can graze the paddock again. The length of time it takes the paddock to recover to an acceptable grazing length depends on factors such as the time of the year and the pasture species. If the situation occurs where none of the paddocks are recovered enough for grazing then the horses should be confined to the yards until they are.

Limited Grazing
This is the practice of removing horses from the pasture for part of each day in order to either conserve the pasture or to limit the amount of feed the horse consumes. This should still be carried out in conjunction with other systems such as rotation, strip grazing etc as the paddocks will still require a period of weeks or months with no grazing pressure and for paddock management practices such as harrowing to be carried out.

Limited grazing is a good strategy for making your available pasture last as long as possible. The horses must spend at least four hours and maybe as many as twelve hours (on good pasture) away from the paddock in order for conservation of pasture or reduced feed intake to be effective because horses will simply condense all of their eating time into the one long session if necessary. This said, removing horses for a few hours each day while not reducing their total daily intake will reduce the amount of time spent loafing or sleeping in the paddock which will reduce land degradation. Horses cause just as much damage if not more to the land during these behaviours as when they are grazing. Another alternative is to let the horse graze for two or even three shorter periods per day rather than one long one.

Part 3 will include cross, strip and block grazing management.

Garlic Overdose Research

A popular ingredient in many equine feeds and supplements, freeze dried garlic researchers have warned that excessive doses of the nutrient can lead to potentially fatal aneamia.

Research in humans has shown garlic to have anti-cholestrol, anti-parasitic and antibiotic properties, leading horse owners to use the additive for nearly a decade. Although garlic overdose is known to cause anaemia in dogs and sheep, the potential for similar dangers in horses has not been documented until now.

An article published in 2001 recommending against feeding garlic to horses prompted a study by Guelph University in the US. For the study, two healthy horses were fed progressively increasing daily dosages of freeze-dried garlic in a mollasses base for 71 days, while for the same period two other healthy horses were maintained on an identical diet but without garlic.

Blood samples collected weekly and analysed for changes showed that when the garlic dosage reached 0.2 grams per kilogram of bodyweight (approx two cups daily), the horses developed initial indication of Heinz body anaemia, a condition in which red blood cells die at rate faster than the body can replace them.

Anaemia can be fatal if the number of red blood cells fall below a critical threshold and the blood can no longer efficiently transport oxygen. The condition is usually reversible if the offending substance is removed from the diet. More advanced clinical signs can include unexplained lethargy, weight loss and weakness. The bloodwork returned to normal after the horses stopped receiving the high doses of garlic within about five weeks.

Although it is highly unlikely that any horseowner would feed their horse such large quantities of garlic, it is worth bearing in mind that the horses in the study were easily able to consume the high dosage without force feeding. Unexplained signs of anaemia should be checked by a veterinarian to identify the cause.