Prickly potential: cactus as grain alternative for dry climates

Cactus is emerging as an economical and high energy forage option for livestock producers in drylands, although its lower protein content could be a limiting factor.

The succulent is increasingly being used in Brazil, Tunisia, Algeria, Morocco, South Africa and India as a feed component, Harinder Makkar, of the FAO’s Animal Production and Health Division, told FeedNavigator. 

“It is a crop for dry areas; its water use efficiency is very high, it can grow in harsh conditions, and it gives good yields - 20 tons of dry matter or 200 tons of fresh per hectare, he said.  

Its high water content also adds to its appeal for farmers in dry areas; cactus is made up of 90% water and 10% dry matter, which makes it a dual source of water and feed, so animals do not need as much drinking water.  

Big in Brazil

Interestingly though, the biggest and most established user is Brazil, where 600,000 hectares of cactus cultivation shields livestock producers from the price fluctuations that grains are subject to.  

There, Makkar said dairy cattle producers were typically incorporating fresh cactus as 60% of an animal’s diet, with the other 40% made up of 20% hay and 20% soy or other form of protein concentrate, and were still achieving milk yields of 20-25 liters per day.  

In addition, he said livestock farmers in Brazil were including cactus in feed formulations to reduce cost.  

“As a high yielding forage option it reduces the cost of feed substantially, even though the energy value is 75% that of maize, so more cactus is needed to achieve an equivalent energy intake, he said.  

Besides offering significantly higher yields than maize (almost 20 times higher, according to Makkar) in semi-arid areas, the use of cactus as animal feed could decrease food-feed competition, because it can be grown on land that doesn’t compete directly with grain production. These factors also lower the cost of cactus production, which in turn lowers the cost of feed production. 

“Cactus can be grown in very poor soil where grains would not grow or their yields would be very low, said Makkar. 

In Brazil, farmers are adding fresh chopped cactus to feed rations, but in some other parts of the world, such as South Africa, cactus is processed into a dried substance that can be added in concentrate form. This also enhances the shelf-life of cactus and gives the feed industry the option of using it as a feed ingredient in compound feed production.  

Makkar warned, however, that carbohydrate-rich cactus should not be used as a sole feed source, owing to its low (5%) protein content. 

Fed as a sole feed source it leads to diarrhea and weight loss; it has to be mixed with other protein-rich components such as soymeal or other legumes and forages such as hay,he cautioned.  

Producing a higher protein content

He conceded that the low protein content of cactus was a limiting factor. However, because of the lack of genetic variability in the cactus varieties that are being grown outside Mexico, he said that conventional cross-breeding methods weren’t an option for producing a higher protein variety.  

All cactuses that are being grown overseas originate from the same genetic material. This means you can’t manipulate the germplasm because there is very little variability to exploit. 

Consequently, he said that irradiation with gamma rays or use of chemical mutagens was probably the only means of producing a higher protein cactus. 

That said, within Mexico, he believes there is some variability which can be exploited to increase the protein content via conventional breeding. 

“I think this area needs to be the focus of research going forwards, he said.