| dc.description.abstract | The study was conducted in Wukro Wereda eastern zone of Tigray to identify and record the
Opuntia varieties found in the area, to retrieve and document indigenous technical knowledge
on management and uses of Opuntia varieties and to evaluate the feed value of Opuntias to
livestock. The methods employed were interviews using a semi-structured questionnaire, field
survey of Opuntias and evaluation of chemical composition and feeding trials using sheep.
The survey results indicated the existence of two varieties of Opuntia in the area, namely
spineless and a spiny cactus. The spineless variety is the dominant one. Forty percent of the
farmers in the area have cactus land ranging from 0.01 to 0.039 ha, 27% of the farmers possess
cactus land ranging from 0.04 to 0.1 ha and 30% own cactus land ranging from 0.11 to 0.5 ha
with an average land q/'0.11 ha. Cactus is important economically and ecologically in six main
wqys namely; source of human food, livestockfodder, hedge, bee forage, soil erosion control and
source cash. All farmers (100%) feed cactus mainly for cattle; while 63% feed it for sheep.
Ninety six percent of the farmers feed cactus to their animals daily during the dry season while
the rest (4%) feed cactus to their animals every other day or every! three days. Burning and
scraping are the two common processing methods used to remove the spines before feeding. In
spite of the extra work and fuel involved in feeding a spiny cactus to livestock, this is becoming
normal practice in a dry season. The survey result also revealed that bloat and diarrhoea are
the main problems associated with feeding of a cactus to livestock and the reasons for the
problems include an excess intake of cactus and feeding it alone.
Samples takenfrom plants grown in natural conditions were analysedfor DM, CP, ash, CF, EE.
NFE., NDF, ADF, ADL and mineral concentrations (P, Ca, Mg, Na and K). Moisture
concentration was extremely high (92.5%), while CF, EE, P and Na concentrations were low;
12.26, 3.23, 0.28 and 0.14%, respectively. There was a significant (P<O.05) difference in P, Ca,
Mg, K, ash and EE concentrations between the two varieties. Compared with ruminant nutrient
requirements, Opuntias were high in ash, APE, Ca and K, moderate in CP and Mg and low in
EE, CF, P and Na contents.
The statistical analysis of the data showed no significant (P>O.05) difference between the two
Opuntia varieties in terms of voluntary feed intake and n~ Digestibility. Cactus was a
palatable, sheep-preferred cactus to tef straw. The total daily DM intake of sheep fed on a
burned spiny cactus averaged 2.2% of their live body weight and 2.5% of their live body weight
for those fed on a spineless cactus. Cactus varieties were also highly digestible (69%). Hence,
it is concluded that Opuntias can serve as a link between crop residues, forages such as legumes
and NPN sources by supplying readily digestible organic matter. However, for a normal diet
intended to cover both maintenance and production requirements, the ration must be balanced
with supplementary protein and phosphorous. | en |
