Atriplex halimus is mainly used to feed small ruminants and particularly sheep (Kadi et al., 2016; Boussaid et al., 2004). As shown below, it can partly or totally replace cereal straw as forage in diets supplemented with concentrates without decreasing animal performance. However, because its composition may vary widely depending on the season, leaf:stem ratio, location etc. results can also be variable. Atriplex halimus can be used as forage source for maintenance, but must be supplemented with energy when growth or milk production is expected. Also, due to its high sodium content, clear water must be freely available. Finally, because high oxalic acid content may occurs, mineral supplementation must be adapted in order to limit calcium deficiency (see Caution).
Intake
Atriplex halimus has been reported to be well accepted by livestock: fairly palatable for sheep and goats during the wet season but poorly palatable during the dry season (El Shaer, 2010; Wills et al., 1990). However, in a cafeteria trial with goats and sheep comparing 3 Atriplex species and 3 legume trees (Acacia and Cassia), Atriplex species were the less preferred species: particularly, animals ate Atriplex halimus at less than 5% of the total intake within 15 min (Degen et al., 2010). When compared to straws, hays or olive leaves incorporated into a total diet at 72 % and offered to sheep (42 kg BW), the dry matter intake (DMI) was lower (0.83 vs 1 to 1.1 kg DM) for saltbush than for all other forages, but the OM digestibility was the highest with 71% compared to 60 to 68% (Abbeddou et al., 2011b).
When animals are not used to consume saltbush, an adaptation period of about 4 weeks is recommended (Valderrabano et al., 1996). DMI of sheep and goats grazing saltbush as sole pasture increased to 72-78 g DM / kg BW0.75. Simultaneously, water intake almost doubled in comparison with control diet. Goats selected twigs with higher diameter (4.6 mm) than sheep (2.7 mm)(Otal et al., 2010; Valderrabano et al., 1996).
When fed alone to rams or lambs, the DMI of saltbush was low (36 to 48 g DM/kg BW0.75) when sodium chloride content was high: 146 vs 93 g/kg DM and 63.1 g/kg DM (Abu-Zanat, 2005; Alicata et al., 2002). When saltbush with high sodium chloride content (63.1 g/kg DM) replaced alfalfa hay, DMI decreased down to 40 g DM / kg BW0.75 while water intake increased from 7.4 to 10.6 l/day (Abu-Zanat et al., 2005). Such values (6.5 to 13 L/kg DM intake) were observed with sheep and goats fed with Atriplex halimus with high (93 – 146 g/kg DM) sodium chloride content (Alicata et al., 2002).
When saltbush from Canary islands was offered as sole diet to male goats in Autumn, the DMI (17 g / kg BW0.75) and the DM digestibility (38%) were very low probably because the low protein content (7.5 g/kg DM) (Alvarez et al., 2008).
Saltbush could be ensiled with molasses and fed to ram supplemented with 300g/d barley grain without any problem and the DMI is about 33 g DM/kg BW0.75 (Alsersy et al., 2015) Adding commercial cellulolytic enzymes into the silage, increased the DMI up to 64 g DM/kg BW0.75 (Alsersy et al., 2015.)
Digestibility
When saltbush was fed alone to rams, DM digestibility varied from 56 to 71% depending on the season (Alicata et al., 2002). The OM digestibility in the rumen is potentially high with 76% as well as the crude protein digestibility with 92% (Abbeddou et al., 2011b). This makes Atriplex halimus good forage either as sole forage or as supplement for stimulating the digestion of poor quality forages like straws.
Sheep
Atriplex halimus and Salsola vermiculata sown on natural rangeland in a semi-arid area in Syria improved biomass production for several years, which in turn increased animal performance. Over seven consecutive seasons, whatever the stocking rate (from one sheep per 2.25 ha/year up to 1 for 0.75 ha/year), milk yield and ewe body weight of Awassi ewes increased compared to ewes on natural rangeland, and lamb growth also increased. In such a system, supplementation was reduced and profit increased (Osman et al., 2006).
| Country |
Breed / Physiological stage |
Experiment |
Level of Saltbush |
Main results |
Reference |
| Italy |
Comisana lambs (33 kg) |
Lambs grazed for 51 days, Atriplex supplemented or not with barley straw ad libitum and 200 g/d of barley grain |
Grazing ad libitum |
Without supplement, lambs lost weight (- 60g/d) and with supplement gain about 60 g/d |
Stringi et al., 2009 |
| Jordan |
Awassi lactating ewes (58 kg) |
Atriplex sp. replacing barley straw plus 4,5 kg concentrate |
50 or 100 % |
Atriplex can totally replace barley straw and gives the same results for milk production or lamb growth rate |
Abu-Zanat et al., 2006 |
| Jordan |
Awassi lambs (23 kg) |
Atriplex sp. replacing barley straw plus 1.1 kg concentrate |
0,2 kg DM |
Total DMI is lower with Atriplex than with straw (0,96 vs 1,12 kg DM/d) but daily weight gain is not different (193 vs. 205 g/d) |
Alazzeh et al., 2009 |
| Jordan |
Awassi lactating ewes (55kg) early lactation |
Atriplex sp replacing barley straw plus 1,5 to 0,9 kg concentrate according to lactation stage |
0,2 kg DM/d/ewe |
Atriplex sp. can totally replace straw and gives the same results as milk production or lamb growth rate |
Alazzeh et al., 2004 |
| Jordan |
Awassi lambs (15 kg) |
Atriplex dried, grinded and incorporated into a total diet replacing 25 or 50% of wheat straw |
7 or 15 % DM |
No difference in DMI, water intake, daily weight gain or carcass quality |
Obeidat et al., 2016 |
Goats
Saltbush supplemented with barley could be used for kid fattening without adverse effects on their growth and meat characteristic (El Shaer, 2010).
