By Charl van Rooyen
The leaves of the camel thorn tree could effectively replace commercial feed ingredients in livestock rations, particularly for livestock farmers in remote areas with limited access to supplemental feed.
Research has now confirmed what livestock farmers have long known, that the camel thorn tree is an invaluable resource for animal feed. Traditionally, farmers mill the dried pods and mix the powder with other ingredients to create a supplemental feed for their livestock, primarily as drought fodder. The latest study has shown that the tree’s leaves are equally nutritious. A chemical analysis of the leaf meal showed, for example, that it’s rich in protein (13 g/kg crude protein).
In the drier regions of Southern Africa, especially in the Kalahari, farmers rely on the pods of camel thorn trees (Vachellia erioloba) when pasture becomes scarce. Livestock also eagerly consume the pods as they fall from the trees.
A research team from North-West University (NWU) and the University of the Free State (UFS) has proven that supplementary feed made from camel thorn leaf meal mixed with ammoniated maize fodder was not only suitable for lambs but may also improve the meat quality. According to an NWU press release, the researchers found that this diet produced meat with greater tenderness and a healthier fatty acid profile compared to lambs on other diets.
The study
The study, published in the Meat Science Journal, was conducted by Prof Upenyu Marume and Dr Getrude Manakedi Chelopo of NWU’s School of Agricultural Sciences and its research niche for food security and safety, in collaboration with Prof Arno Hugo of the UFS’s Department of Animal Science.
Prof Marume told African Farming that they wanted to determine whether camel thorn leaves could be successfully added to a feed ration to replace a purchased source, especially for farmers with limited access to high-quality feed. Camel thorn trees are evergreen, and even have leaves during times of drought. For the trial, they harvested leaves at the growing tips, let them air-dry in the shade for three days, and then milled them.
The trial was conducted on NWU’s experimental farm in Mahikeng with 32 five-month-old Meatmaster ewe lambs divided into four groups, which were allotted four dietary treatments. The first group (the control group) received a regular lamb finishing ration (LFR) with lucerne as roughage; the second group received LFR in which the lucerne was substituted with 20% untreated maize fodder; the third group received LFR with 20% ammoniated maize fodder; and the fourth group received LFR with 10% ammoniated maize fodder and 10% camel thorn leaf meal.
The results
The growth test began after a seven-day adjustment period. The trial lasted 60 days. The average daily feed intake did not vary much between the groups (1,21–1.39 kg/day), nor did the average daily weight gain, which ranged from 0,20–0,24 kg/day, and feed conversion ratio, which ranged from 5,36–6,54 kg/kg.
The control group had a high average daily feed intake, as expected, because the LFR is formulated with the most ideal ingredients for lambs, with high palatability. Interestingly, the inclusion of the leaf meal in the fourth group’s diet resulted in higher average feed intake, suggesting it made the feed even more palatable.
The fourth group’s meat had the highest water-holding capacity, resulting in greater tenderness and juiciness. It also contained the highest levels of desirable fatty acids, particularly total unsaturated fatty acids.
The study successfully demonstrated that camel thorn leaf meal can serve as an affordable and sustainable alternative to conventional feed.
Enquiries: Prof. Upenyu Marume, 081 039 0670, upenyu.marume@nwu.ac.za