Fat supplementation affects the lactational performance of goats and dramatically changes milk nutritive value. In the present experiment, two levels of Nannochloropsis oculata microalgae, a natural source of rumen-protected eicosapentaenoic acid (EPA), were studied in the diet of Nubian goats. Using quintuplicated 3 × 3 Latin square design, fifteen lactating goats, (14 ± 2 months old and 33.0 ± 1.3 kg) after kidding, were randomly assigned into three treatments in an 84-d assay. Goats were offered a basal diet comprising berseem clover, wheat straw and concentrates in 3:2:5, respectively, (control treatment-no supplementation). The other two treatments were supplemented with N. oculata microalgae at 5 g (NOM5 treatment) or 10 g (NOM10 treatment)/doe/d. Without affecting intake, treatments improved (p < 0.01) nutrient digestibility. Supplementations had no effect on ruminal pH and ammonia-nitrogen, however, NOM5 and NOM10 linearly improved (p < 0.05) total volatile fatty acids and propionic acids. N. oculata supplementation linearly increased (p < 0.01) milk yield and lactose content. Supplementation reduced atherogenic index (p = 0.004) and enhanced the concentrations of unsaturated fatty acids and C20:5n3 (EPA). Conclusively, feeding Nubian goats on diet supplemented with N. oculata at 5 and 10 g improved milk production and the nutritive value. No improvements in the performance were observed when N. oculata dose was increased from 5 g to 10 g/doe; thus, 5 g dose is recommended for use.

Eighteen 4-month-old lambs, with a mean live weight (LW) of 19.47 ± 0.20 kg, were used to evaluate the nutritive value of date palm leaves (DPL) ensiled with different additives in a completely randomized design. Lambs were stratified into three groups of 6 lambs each and fed a control diet comprising 60% concentrate feed mixture (CFM) and 40% DPL silage (T1). In other treatments, the DPL silage (DPLS) of the control treatment was replaced with EM₁ additive-treated DPLS (T2) or El-Mofeed additive-treated DPLS (T3). Apparent digestibility, total digestible nutrient, digestible crude protein, dry matter intake, daily weight gain (DWG), price of DWG, daily profit, and economics of feed efficiency were higher (P < 0.05) for the additives-treated DPLS relative to the control, with T2 enhancing these parameters compared with T3. With exception of ruminal pH, which was reduced, concentrations of ruminal NH₃-N and total volatile fatty acids (VFA) increased 4 h post feeding. However, ruminal NH₃-N and total VFA were greater (P < 0.05) for the additives-treated DPLS, with T2 producing higher values than T3. Ruminal pH and feed cost/kg LW gain were lower for T2 relative to other treatments. Blood constituents were within the normal ranges for lambs, though slightly altered by treatments. Whereas serum total protein, albumin, and globulin were affected (P < 0.05) in this rank order, T1 < T3 < T2, other serum parameters were not affected. Relative feed cost and relative daily profit were lower and higher respectively for T2 than for T3. It is concluded that additives-treated DPLS is nutritionally superior to untreated DPLS as a roughage source in total mixed rations fed to growing lambs. However, for improved performance of the lambs and economic benefits, EM₁-treated DPLS is recommended.

The present experiment evaluated the feeding of date palm leaves (DPL) ensiled with fibrolytic enzymes (ENZ) or multi-species probiotics (MSP) on nutrient utilization and lactational performance of ewes. Fifty multiparous lactating Farafra ewes were used in a completely randomized design for 90 d. The treatments consisted of the control diet with a concentrate feed mixture and date palm leaves (at 60:40, DM basis) ensiled without additive (control) or DPL ensiled with ENZ or MSP replacing control DPL at 50 or 100%. Both ENZ and MSP increased (p < 0.01) DPL and total intakes, digestibility of all nutrients, concentrations of ammonia, total volatile fatty acids, acetate and propionate in the rumen. Increased milk production, concentrations of fat, lactose and energy in milk, and feed efficiency were observed with MSP and ENZ compared to the control treatment. Moreover, ENZ and MSP increased (p < 0.05) the concentrations of total n3, n6 fatty acids, polyunsaturated fatty acids and conjugated linoleic acids and decreased (p < 0.001) the atherogenicity. The differences between ENZ and MSP and between the low and high replacement levels were minor for all measured parameters. Ensiling of DPL with MSP or fibrolytic enzymes is recommended to improve feed efficiency and improve lactational performance of ewes.