Just like the fruit of the cactus pear plant can be utilised in various ways, the leaves (also known as cladodes) hold significant value. There is great potential to use this plant in the livestock production industry, but it remains underexplored and underutilised in Southern Africa.

Farmers can learn a lot from countries such as Brazil and Mexico, where cactus pear has played a vital role for centuries and is often used as the primary source of livestock feed.

One of the main reasons cactus pear is considered a valuable fodder crop is because it:

• Is drought-resistant and produces when other fodder crops fail;
• Is widely adaptable in terms of climate and soil preference;
• Yields higher than pasture crops due to superior water-use efficiency;
• Can be used and processed in various feed forms;
• Is easy to establish;
• Has low establishment costs;
• Is suitable for both smallholders and commercial operations;
• Is a good-quality feed;
• Is highly palatable; and
• Is highly digestible.

Nutritional value

Cactus pear primarily serves as an energy source and contains relatively low crude protein (around 2 to 3%). However, with proper fertilisation, crude protein levels can be increased to about 8%. Research confirms that cactus pear can serve as a useful maintenance feed. In arid regions, its high moisture content is especially valuable; up to 90 000 litres of water can be stored in the leaves per hectare when producing 100 tonnes of dry matter.

However, this moisture content can limit the intake of sufficient nutrients.

Drying cactus pear leaves is complicated by the presence of mucilage, a water-soluble, pectin-like polysaccharide that binds water. This mucilage plays a key role in the cactus’ ability to retain moisture under harsh climatic conditions such as drought.

Although cladodes (cactus leaves) are widely used as drought feed, knowledge about their value in high-production livestock diets remains limited. In 2005, Desirée Zeeman conducted a study in which young Dorper wethers were fed diets where lucerne hay was partially replaced with sun-dried, coarsely ground cactus leaves at levels of 0%, 12%, 24%, and 36%. Even at the highest inclusion (360 g/kg diet), there was no negative effect on growth performance, in fact, digestibility improved as cactus pear levels increased.

These findings were confirmed in 2008 by Ockert Einkamerer in a similar 63 day trial with young Dorper wethers. Animal performance and carcass quality were not negatively impacted by cactus pear intake.

Another important insight from this research is that mucilage in the cladodes contributes to watery faeces. Since it is not broken down in the digestive system, it binds water that would otherwise be absorbed in the small intestine. The additional water intake observed in sheep consuming dried cladodes is thus not excreted via the kidneys, but largely through watery faeces (De Waal et al, 2015) — a condition sometimes mistakenly attributed to laxative effects.

Palatability

Cactus pear is highly palatable to animals, which is why it’s important to protect plantations from grazing. In areas where wild animals like kudu can easily cross fences, it is nearly impossible to establish a successful plantation. Animals such as hares, porcupines, and even tortoises also enjoy the juicy leaves, making proper fencing and protection essential for sustainable production.

Utilisation options

Cactus pear can mainly be utilised in two ways: fresh or dried, with each option further processed as needed. During droughts, all parts of the plant, including roots, stems, and leaves, can be used as feed. In cases of extreme food shortage, all leaves and side branches can be cut down to about 0,5 metres above ground level.

To ensure long-term productivity, only light pruning should be done in the following season. If thicker stems are used, they must be chopped into smaller pieces to facilitate intake by animals. Traditionally, fresh cladodes are sliced into strips or cubes and fed directly to livestock. Sometimes, the material is first shredded or chopped and partially dried before being used as feed.

The high moisture content of fresh cladodes creates challenges in handling, processing, and intake. Practical and efficient methods of cutting and drying the leaves can significantly ease further processing. In dried form, cladodes also offer the benefit of easier adjustment of nutrient composition for balanced feed rations. A partial drying process can be used to reduce excess moisture before further processing.

Leaf or cladode production

With annual pruning, an expected yield of about 100 tonnes of fresh material per hectare can be achieved — equivalent to roughly 10 tonnes of dry matter per hectare. This is based on a planting density of 666 plants per hectare. In intensive systems where cactus pear is used exclusively as livestock feed, yields of up to 400 tonnes of fresh cladodes per hectare (equal to 40 tonnes dry matter) have been recorded.

Chopping and drying of cladodes

Various types of equipment, such as multi-purpose cutters or adapted choppers, can be used to cut fresh cladodes efficiently. The goal is to slice the leaves into thin strips or slices to increase surface area and speed up the drying process in the sun. The thinner the cuts, the faster the material dries, but care must be taken to avoid pulping the cladodes. Excess damage releases mucilage that coagulates on the surface and slows down moisture evaporation. Since this mucilage binds water, it is also not possible to press the cladodes to remove moisture.

The chopped material is sun-dried on drying floors or racks raised above ground to allow adequate air circulation. The drying period ranges from four to fourteen days, depending on cut thickness, weather, and further processing. Using sharp blades is crucial to minimise cell damage — too much bruising releases mucilage that makes the material sticky and difficult to handle.

The next step in utilising cladodes involves formulating specific production diets with dried material and testing these on animals in different production stages such as lactation or finishing. As research progresses, application will expand to include cattle. The interaction between mucilage and water, both during drying and in the ruminant digestive system, remains a key focus of further study.

Grazing of cactus pear

In the past, direct grazing of cactus pear, especially during droughts, was recommended. Over time, however, it became clear that this practice had drawbacks. Opportunistic grazing often led to poor utilisation of plant material and decreased long-term productivity of plantations. As a result, experts now advise against direct grazing of cactus pear.

As with any intensive production system, using cactus pear for livestock feed carries certain risks — particularly overgrazing, uneven utilisation, and its impact on orchard longevity. However, the benefits of a well-managed cactus pear feeding programme are significant. When used not only as emergency feed but as a sustainable component of the farm’s feed production strategy, it provides valuable year-round support.

In countries like Brazil, such programmes have been successfully implemented for many years. It has been proven that cactus pear can yield high returns in intensive systems with excellent utilisation, especially in young plants, and long-term productivity when managed properly.

Use of cactus pear fruit in animal production

When fruit is not the main product of the plantation, a significant portion of the harvest can be used as livestock feed. Various studies indicate that 25 to 30 tonnes of fruit per hectare can be produced. In some cases, farmers focus exclusively on seed production, making the fruit pulp a by-product that can be fed to animals.

Fully ripe cactus pear fruit contains around 12% natural sugars, mainly glucose and fructose, making it a highly palatable and energy-dense feed source. The biggest challenge with using fruit as feed lies in its short shelf life — only a few days post-harvest. This necessitates rapid utilisation or preservation. Suitable preservation methods include silage production or processing into feed blocks.

Feed blocks

In agriculture, several waste or by-products from processing are often discarded. Examples include olive cake, grape skins, citrus peels, tomato pulp, and cactus pear fruit. A major challenge is their limited shelf life, requiring prompt use. One practical and innovative solution is the production of feed blocks.

In resource-limited countries, feed blocks are considered a valuable innovation in animal nutrition (Nasri, 2008; Nefzaoui, 2007). The ratio of ingredients depends on the desired nutritional quality of the feed block. Surplus fruit or waste from sorting lines is often used as an energy base in formulations.

Dried feed blocks have the advantage of long-term storage, making them ideal for use during droughts. They can also be used in winter and early spring as a supplementary feed source to support animal nutrition.

Cactus pear silage

Some farmers use fresh cactus leaves to produce silage, but this method requires practical skill and careful management. Because of the high moisture content, silage can easily spoil. Success also depends on the sugar content of the ensiled material. When leaves are partially dried before ensiling, outcomes improve significantly.

A common practice is to mix chopped cladodes with a drier roughage such as maize stalks or grass to balance the moisture content. An effective ratio is five parts ripe, pulped fruit to one part dry material. If needed, supplements such as feed urea and microminerals can be added. The mixture is then processed using standard silage techniques. To ensure high quality, exposure to air must be minimised, as oxygen accelerates spoilage.

If properly executed, cactus pear fruit can form an excellent basis for high-quality silage, without the need for additional molasses (De Waal, 2015).

In Part 5, we shall look at cactus pear for human consumption. For more information, visit Witkraal Boerdery’s website at www.witkraal.co.za.

 

Source:
Witkraal. (2022, March). Cactus Pear as Livestock Feed [PDF]. Witkraal Boerdery.