Black cumin meal (Nigella sativa) as an alternative feed resource during the suckling period of Awassi ewes: Assessments of performance and health

This study was designed to investigate the effectiveness of different Black cumin meal (BCM) dietary treatments during the suckling period on lactating performance and health of multiparous Awassi ewes. We randomly allocated 27 nursing Awassi ewes (4-5 years age; 50.2 +/- 1.42 kg body weight) to one of three equally dietary treatments: 1) control diet, no feed BCM (CON), 2) BCM50 diet (50 g/kg of dietary dry matter (DM) and; 3) BCM100 diet (100 g/kg BCM of dietary DM). The results showed that there are no significant differences at P >= 0.67 among the three treatment groups in measured parameters like intakes of DM and crude protein (CP). However, the BCM100 group showed greater (P < 0.0001) ether extract (EE) intake compared to both the BCM50 and CON groups and ewes exhibited greater (P < 0.02) metabolizable energy intake in BCM100 and BCM50 groups than the CON group. The digestibility of CP and neutral detergent fiber improved (P < 0.05) in the BCM100 and BCM50 diets compared to the CON diet. The acid detergent fiber digestibility tended to be higher (P = 0.08) in the BCM100 and BCM50 diets compared to the CON diet. However, the digestibility of DM and EE did not show significant differences (P >= 0.17) among the three treatment groups. Nitrogen retained as (g/d) and retention as a percentage (g/100 g) were greater (P < 0.01) in the BCM100 and BCM50 diets compared to the CON diet. The final body weight and average daily gain of the lambs in the BCM50 and BCM100 groups increased compared with the CON group (P < 0.02). The BCM100-treated group had greater milk yield per day (P < 0.05) compared to the CON group. The content of fat, protein, lactose, solid-not-fat (SNF), and total solids (TS) % did not differ among the three groups. The BCM100-treated group had higher (P < 0.03) fat and TS milk yields (g/d) compared to the BCM50-treated group and CON group. However, fat and TS milk yields were similar between the BCM50 treatment group and the CON group. The BCM100-treated group had a greater SNF yield per day (P < 0.05) compared to the CON group. However, SNF yields in BCM treatment groups and between BCM50 group and CON group were similar. Moreover, the average protein and lactose yield of milk were significantly higher in the BCM100 diet than CON diet. Feed efficiency tended to be greater in BCM-treated ewes than the CON ewes. Moreover, the cost/kg of milk produced was lower (P < 0.01) in the BCM diets than in the CON diet. Ewes fed a BCM100 had higher energy-corrected milk than other groups. The analysis did not detect differences in the blood serum metabolites in all treatments. In conclusion, this study suggests that dietary inclusion of different levels of BCM showed a positive influence on most lactating characteristics and economic performance for the lambs and lactating Awassi ewes, and could be used as a good alternative feed source in ruminant feeds.