Jojoba foliage is a browse resource that is relished by cattle, rabbits, goats and deer (hence the names "goat nut" and "deer nut") (Matthews, 1994; Duke, 1983). In the South-Western USA, jojoba is particularly important for mule deer (Odocoileus hemionus) in autumn and winter. Cattle may browse jojoba severely enough to prevent any fruit development, and often consume it faster than it grows (Matthews, 1994). There is little information available in the literature about the nutritional value of jojoba forage for ruminants. Reported values of in vitro DM digestibility are low, in the 36-47% range (Matthews, 1994).
Jojoba oil meal
Due to the presence of simmondsin and other antinutritional factors, jojoba oil meal has deleterious effects on DM intake and sometimes on performance (growth) in ruminants when included in the diet at more than 10%, even though rumen microorganisms have been shown to detoxify 95% of the simmondsin within 6 h in sheep (Manos et al., 1986; Verbiscar et al., 1980). When jojoba meal is detoxified by physical, chemical or bacterial treatments, it becomes possible to include it at up to 30% of the diet without affecting DM intake and performance.
Jojoba oil meal is not very palatable to ruminants. Steers offered a pelleted diet with or without 10% jojoba meal preferred the pellets without (Verbiscar et al., 1981). Lambs that could choose their diet freely refused the diet containing untreated jojoba meal, while lambs given no option ate only 50% of their normal intake (Verbiscar et al., 1980). Jojoba oil meal ensiled with chopped maize plants was largely rejected by lambs when the meal was included at 20% in the silage, but they ate normally when 5 and 10% meal was included (Manos et al., 1986).
Steers fed a diet containing 10% detoxified jojoba oil meal had the same DM intake but a lower weight gain (by 16%) than steers fed a control diet without jojoba meal (Verbiscar et al., 1980).
Jojoba oil meal included at 10, 20 or 30% in a concentrate offered with bean straw to growing lambs (20.8 kg) for 98 days did not alter DM intake but daily weight gain was depressed (46-97 g/d vs. 216 g/d without jojoba meal), although DM digestibility tended to increase with increasing jojoba levels. Lambs fed with high jojoba level showed higher liver enzyme levels indicating liver and other tissue problems (El-Kady et al., 2008). Jojoba meal added at 20 or 30% in lamb diets decreased DM intake by about 50% and did not support any weight gain. Animals fed with 20 or 30% untreated jojoba meal did not show differences in their organs or pathology compared to control lambs (Verbiscar et al., 1980). Untreated jojoba meal included at 10% of the diet, or detoxified jojoba meal included at 10 or 30% of the diet had no effect on DM intake and growth (Verbiscar et al., 1980; Verbiscar et al., 1981). Jojoba meal treated with fungus and included at 10% in a concentrate improved DM and OM digestibility, and increased daily weight gain (Khalel et al., 2008).
When jojoba oil meal was included at 0, 5 or 10% in a complete diet and fed ad libitum to Creole dairy goats, DM intake decreased from 2.6 to 2.2 kg as jojoba level increased, with no effect on weight gain (184-221 g/d), although it tended to be lower (184 g/d) with 10% jojoba. Milk yield was higher with 5% jojoba (428 ml/d) than with 0% (270 ml/d) or 10% (196 ml/d), but there was no effect on milk composition. The 5% inclusion level gave the best performance (Azocar et al., 1990).