Sadeghi, M.-H., Sari, M., Mohammadabadi, T. et al. 2019. Effect of a short-term training on intake of Halocnemum strobilaceum forage by sheep. Applied Animal Behaviour Science 213, 74-80.
Halocnemum strobilaceum (Chenopodiaceae) is a halophyte plant that can produce relatively high consumable biomass during drought and it is important for sustaining grazing animals when other plants are rare. Previous studies indicate that sheep may avoid the plant due to its novelty or neophobia. This study determined whether prior exposure of sheep to H. strobilaceum influence its later intake. Thirty-six 12-month-old Arabian fat-tailed ewe lambs were divided into 6 experimental groups: 1. Control group (C) that was fed a basal diet, 2. Control drench group (CD) that was received oral drench of water in addition to basal diet, 3. Halocnemum drench group (HD) that was received the pulp of Halocnemum in addition to basal diet, 4. Control training group (CT) that was fed an additional 200 g of basal diet for the whole training period, 5. Halocnemum training group (HT) that was fed a basal diet and some Halocnemum plant or novel feed and 6. Novel feed training group (NFT) that fed a basal diet and 200 g air-dry novel commercially available feeds. Animals were given different feed training experiences during 10 days. Following the completion of the training, preference tests were conducted for all treatments using fresh or dry H. strobilaceum at either 5% or 20% concentration (based on DM) in alfalfa hay. Sheep that had been exposed to H. strobilaceum forage during training increased their consumption of H. strobilaceum (7.48 ± 0.49 vs. 4.31 ± 0.54 g DM/5 min; P < 0.001) during subsequent feed preference trials. However, the relative preference did not increased by training method for H. strobilaceum when it was presented in combination with another feed. The intake of H. strobilaceum was affected by the form (fresh vs. dry; 9.08 ± 0.38 vs. 2.80 ± 0.15 g DM/5 min; P < 0.001) and concentration (5% vs. 20%; 3.20 ± 0.31 vs. 8.69 ± 0.20 g DM/5 min; P < 0.001) provided in diet and relative preference was higher for feeds with fresh H. strobilaceum included at a rate of 20%. The drenching of H. strobilaceum pulp increased its fresh intake (42 ± 2.48 vs. 16 ± 5.99 g DM/5 min; P < 0.001). Sheep that had been exposed to H. strobilaceum forage in training increased their intake when it was presented as the only feed for a short period of time (1 h). Overall, the results of this study show that avoidance of H. strobilaceum is at least partly due to neophobia, which can be decreased with training to novel feeds that contain H. strobilaceum itself.