Essential oils (EOs) and their active components are attracting a lot of attention as sustainable feed additives due to their known antimicrobial properties against a variety of microorganisms, including bacteria, protozoa, and fungi. They also have biological therapeutic, antioxidant, and flavor properties. They can be used for modifying the rumen environment and improving animal productivity. The present study was designed to investigate the effect of supplementation with 2.5 and 5 g/head/day of an essential oils blend (EOB) of clove, oregano, and juniper in equal proportions on milk production and quality, and physiological status of early lactating Holstein dairy cows for 8 weeks of treatment followed by 8 weeks of posttreatment. The results revealed an improvement in milk yield (p ≤ 0.02) and feed efficiency (p ≤ 0.001) with EOB at a dose of 2.5 g/head/day. The percentages of milk protein and lactose were increased (p ≤ 0.03) with a high dose of EOB inclusion during the treatment period as compared with the control group. Milk fat percentage, fat-corrected milk, and energy-corrected milk were not significantly affected by EOB supplementation. The supplementation of EOB tended to decrease milk total bacterial and somatic cell counts when compared to the control group. The supplementation of EOB at both doses increased serum total protein (p ≤ 0.02) and globulin (p ≤ 0.05), and decreased cholesterol level (p ≤ 0.001) and creatinine (p ≤ 0.001) as compared to the control group. Furthermore, the results show that the low dose of EOB had more desirable effects on milk yield, milk total bacterial count, milk somatic cell count, and feed efficiency than the high dose, suggesting that lower doses may not inhibit rumen microbial populations. Moreover, the low doses of EOB could be used as sustainable natural alternatives to antibiotics in livestock diets.

This study was conducted to assess the impacts of using two essential oils, rosemary and ginger, on growing rabbits’ performance, carcass traits, meat composition, blood biochemicals, and the redux status of growing New Zealand White (NZW) rabbits. A total of 120 unsexed NZW rabbits, 42-days-old, were assigned randomly to five experimental groups (n = 24, 6 replicates with 4 rabbits each). The first group received a basal diet (control), the second to fifth groups were dietary supplemented daily with rosemary essential oil (REO) and ginger essential oil (GEO) at doses of 0.25 and 0.5% for each supplementation (REO-0.25, REO-0.5, GEO-0.25, and GEO-0.5), respectively. The growth traits were studied for 7 weeks, from the 7th to the 13th week of the rabbits’ age. The results revealed that final body weight, weight gain, and average daily gain increased significantly (p < 0.01) in the REO-0.5 and GEO-0.5 treatments compared to the control group. Daily feed intake decreased (p = 0.005) in essential oil treatments. Meanwhile, the feed conversion ratio improved significantly (p = 0.001) in REO and GEO at the high doses compared to the control group. The weight percentages of liver and giblets increased (p < 0.001) with both treatments of REO and GEO compared to the control group. The dietary supplementation with REO and GEO did not affect (p > 0.05) the meat composition of Longissimus dorsi and hind leg muscles. Meanwhile, REO and GEO supplementation significantly decreased cholesterol levels in the rabbit meat. Thiobarbituric acid reactive substance concentrations decreased by 10 and 15% in the meat of REO-0.5 and GEO-0.5 treatments, respectively, compared to the other groups. In the same trend, REO and GEO treatments induced a significant (p = 0.001) reduction in the plasma cholesterol concentrations and triglycerides compared to the control. The total antioxidant capacity increased by 7.60% and the malondialdehyde decreased by 11.64% in the plasma of GEO-0.5 treatment than the control. Thus, the dietary supplementation of REO and GEO have a beneficial effect in improving the productivity and meat quality of growing rabbits.

The demand of functional foods is on the rise, and researchers are trying to develop nutritious dairy products by using well-characterized strains of bacteria. In this study, we identified locally isolated strains of Lactobacillus fermentum from Bubalus bubalis (Nilli Ravi buffalo) milk and evaluated their potential as probiotics in food products like fermented milk. Fifteen Lactobacillus strains were initially isolated, and only four strains (NMCC-2, NMCC-14, NMCC-17, and NMCC-27) were examined for morphological and biochemical characterizations due to their ability of gas production in Durham tubes. Moreover, these strains were selected for further probiotic characterizations due to their extreme morphological resemblance with lactic acid bacteria for their antimicrobial activity, enzymatic potential, autoaggregation capability, hydrophobicity, and acid and bile tolerance. All selected isolates showed significant probiotic potential. However, NMCC-14 and NMCC-17 strains showed maximum probiotic potential. The isolates (NMCC-2, NMCC-14, NMCC-17, and NMCC-27) were identified as Lactobacillus fermentum utilizing 16S rRNA gene sequencing. The in vivo safety study of NMCC-14 (dose: 1010 CFU/day/mice; 21 days, orally) showed no histological dysfunctions in a mouse model. Pathogenic bacterial enzymes reduced the beneficial bacterial load in the host gastrointestinal tract. These results suggest that the NMCC-14 strain is safe and can be potentially used as a probiotic. Moreover, fermented milk was prepared by using the NMCC-14 strain. The results revealed that NMCC-14 strain-based fermented milk had significantly (p < 0.05) higher protein content (4.4 ± 0.06), water-holding capacity (WHC), and dynamic viscosity as compared to non-fermented milk. The results suggest that L. fermentum NMCC-14 is safe and nontoxic; hence, it can be a beneficial supplement to be used for the development of dairy products to be subjected to further clinical testing.

Prickly pear cactus peels (Opuntia ficus-indica, PPCP) are sustainable byproducts available in arid regions and a rich source of antioxidants. Fifteen multiparous Barki ewes (2–3 years old, 46.94 ± 0.59 kg body weight, BW) at postpartum were individually distributed in three equal groups and fed diets supplemented with PPCP at doses of 0, 5 and 10 g/head/day. Lambs were individually distributed into three equal groups according to their mothers’ groups to investigate the maternal effect on lambs’ growth performance, hematology and serum metabolites. This trial lasted for 56 days from birth to weaning. Moreover, nine adult male Barki sheep with a live BW of 65.76 ± 0.54 kg were randomly allocated into three equal groups to determine the effect of PPCP on the nutrient digestibility of the experimental diets. The results indicate that supplementing PPCP at low levels (5 g/head/day) increased milk yield (p = 0.050), fat-corrected milk (p = 0.022), energy-corrected milk (p = 0.015) and the yield of milk constituents compared to 10 g PPCP and the control group. In addition, lambs suckling from ewes fed the diet supplemented with 5 g PPCP had a higher (p = 0.001) weaning BW compared to other groups. Serum total protein, globulin, superoxide dismutase, glutathione peroxidase enzyme activities and the triiodothyronine hormone improved significantly in lambs suckling from ewes fed diets supplemented with 5 g PPCP compared to the control group. Serum cholesterol profile and kidney activities were enhanced significantly in lambs suckling from ewes fed diets supplemented with 5 and 10 g of PPCP compared to the control group. The dietary supplementation of 5 g PPCP improved the crude protein digestibility, digestible crude protein value, nitrogen balance and rumen fermentation characteristics of male sheep compared to the control group. In conclusion, supplementation with 5 g PPCP improved ewes’ milk production, offspring growth and physiological status. Furthermore, it improved the crude protein digestibility and rumen fermentation characteristics of Barki sheep.

Vegetable oils are a source of natural antioxidants, including tocopherols, sterols, phenolic compounds, coenzymes, and polyunsaturated fatty acids that provide nutritional value, organoleptic properties, and significantly delay or prevent lipid oxidation. Eighty-four V-line rabbits at 5 weeks of age with an initial body weight (BW) of 535.60 ± 13.48 g were assigned randomly to four experimental groups (seven replicates in each group with three rabbits each). The first group served as a control and received 0.3 mL/kg BW of distilled water (CON), while the second and third groups received 0.3 mL/kg BW of rocket seed oil (RSO) and wheat germ oil (WGO), respectively. The fourth group received a mixture of oils consisting of 0.15 mL of RSO and 0.15 mL of WGO/kg BW (MOs). The experiment lasted 7 weeks. The study investigated the effects of RSO, WGO, and their mixture on growth performance, feed utilization, antioxidant status, and immune response of growing rabbits. The results indicated that the rabbits that were administered orally with RSO and WGO or their mixture had higher (p ≤ 0.05) final BW, weight gain, and average daily gain when compared to the control group. In addition, the feed conversion ratio improved significantly with RSO, WGO, and MOs treatments. Different oil treatments improved nutrient digestibility, nutritive value, and nitrogen balance. Moreover, the rabbits that received RSO, WGO, and their mixture had an improvement the meat fatty acid composition compared to the control rabbits. Oral administration of RSO, WGO, and their mixture significantly improved serum protein fractions, decreased blood urea nitrogen, and had a positive effect on serum total lipids, HDL-c, and LDL-c. Furthermore, the treatments of RSO, WGO, and MOs had a significant improvement in the antioxidative status and immune response.