Essential Oils from Indigenous Iranian Plants: A Natural Weapon vs. Multidrug-Resistant Escherichia coli

Aim of this study was to investigate the antimicrobial properties of herbal plant essential oils (EOs) from selected Iranian plant species such as Ferulago angulata, Zataria multiflora, Cuminum cyminum, and Mentha longifolia against antibiotic-resistant Escherichia coli (E. coli) strains. For this purpose, the Escherichia coli strains, isolated from raw cow’s milk and local dairy products (yogurt, cream, whey, cheese, and confectionery products) collected from different areas of Hamedan province, Iran, were investigated for their resistance to antibiotics (i.e., streptomycin, tetracycline, gentamicin, chloramphenicol, ciprofloxacin, and cefixime). Thus, the E. coli strains were tested for their susceptibility to the above-mentioned essential oils. Regarding antibiotics, the E. coli strains were highly sensitive to ciprofloxacin. In relation to essential oils, the most effective antibacterial activity was observed with Zataria multiflora; also, the bacteria were semi-sensitive to Cuminum cyminum and Mentha longifolia essential oils. All strains were resistant to Ferulago angulata essential oil. According to the results, the essential oil of Zataria multiflora can be considered as a practical and alternative antibacterial strategy to inhibit the growth of multidrug-resistant E. coli of dairy origin.

​Effect of Dietary Inclusion of Cumin Seed (Cuminum cyminum) on Voluntary Feed Intake, Milk Yield, Milk Quality and Udder Health of Dairy Cows

Background: Plants containing essential oils can be a cost-effective means of improving efficiency of milk production and optimizing milk composition of dairy cows. Cuminum cyminum (green cumin) belongs to the Apiaceae family and is a well-known herbal medicine in Iran. The medicinal properties of cumin may have beneficial effects on milk production. However, very few studies have been reported whereby cumin has been fed to ruminants. Therefore, the present study is design to investigate the effect of cumin supplementation on milk yield, milk quality and udder health of lactating dairy cows. Methods: Twelve multiparous lactating cows at early stage of lactation was selected and randomly allotted to two equal groups (n=6) on the basis of milk yield. In addition to normal routine feeds and fodders, cows in groups T1 was fed cumin seed @ 50 g/d/head for 90 days. Fortnightly body weight was determined on the basis of body measurement of animals. All feed samples was analysed for proximate composition, Ca and P. The daily milk yield (kg/d) of individual cows was recorded by weighing. Milk samples were collected after complete milking and thorough mixing for determination of milk composition. Udder health was monitored by MCMT (modified california mastitis test), measuring milk pH and SCC (somatic cell count) at fortnightly intervals. Result: The results indicated that overall mean body weight, average DMI was statistically (P greater than 0.05) similar in both the groups. The average milk yield (kg) of animals was statically non significant (P greater than 0.05) but numerically 20.64% higher milk yield was observed in cumin seed supplemented group than control group. There was no effect of cumin supplementation on chemical composition (Fat, TS, SNF, Lactose and Protein) of milk in dairy cows. Overall mean milk pH and somatic cell count (SCC) in both the groups was statically similar but numerically lower in treatment group. The overall mean (%) of MCMT positive animals was 14.29 and 9.52 in T0 (Control) and T1 (Treatment) groups, respectively. From the results it can be deduced that the cumin seed (Cuminum cyminum) supplementation improves milk yield by 20.64%. However, it has no effect on composition of milk in dairy cows. Supplementation improved the udder health and found no effect on dry matter intake (DMI) in dairy cows.