Effects of feeding salt-tolerant forages cultivated in salt-alkaline land on intake, average liveweight gain, physiological responses and slaughtering performance in lamb

The objective was to evaluate effects of feeding salt-tolerant forages cultivated in salt-alkaline land on intake, average liveweight gain, physiological responses and slaughtering performance in lamb. Sixty first generation (F1) lambs of a cross between Chinese Inner Mongolian Fine-wool and German Mutton Merino (3.0 ± 0.12 months; 23.5 ± 0.83 kg of body weight [BW]), were arranged into four treatments. Treatments were: control (51% corn stover and 49% concentrate, dry matter [DM] basis), LSTF, MSTF and HSTF in which the mixture of salt-tolerant forages (Dahuria wildrye grass, Weeping Alkaligrass and Erect Milkvetch by a ratio of 45:35:20) replaced either one-third, two-thirds or all of the corn stover, respectively. Lambs were fed twice daily at 0700 and 1900 h with water provided ad libitum during the 60-day growth trial. Average liveweight gain, pulse rate, respiratory rate, rectal temperature, liveweight at slaughter and bone weight were not different between treatments. With increasing the inclusion of salt-tolerant forages in the diet, DM, NDF and ADF intake linearly (P = 0.001) increased to be higher (P < 0.01) for LSTF, MSTF and HSTF diets than for control, but CP intake was unchanged. Feed conversion rate linearly (P = 0.001) increased with the least for control, followed by LSTF, the highest for MSTF and HSTF diets. Carcass weight and meat weight linearly (P < 0.03) increased to be higher (P < 0.02) for LSTF, MSTF and HSTF diets than for control. Dressing percentage, meat percentage and the ratio of meat to bone linearly increased for being higher (P < 0.05) with LSTF, MSTF and HSTF diets than with control. Average longissimus muscle area quadratically (P = 0.005) increased with the least for control, followed by HSTF, the highest for LSTF and HSTF diets. Results indicate that feeding salt-tolerant forages to lambs as partial or sole forage source can be beneficial for increasing feed intake and increase meat production.