Efterpi Christaki

Effect of dietary oregano essential oil on performance of chickens and on iron-induced lipid oxidation of breast, thigh and abdominal fat tissues

1. We studied the effect of dietary oregano essential oil (50 and 100 mg/kg of feed) on the performance of broilers, and determined the susceptibility of the resulting broiler meat to ironinduced lipid oxidation. 2. Performance of the birds was unaffected by the experimental diets. Therefore, dietary oregano oil exerted no growth-promoting effect on broilers. 3. Iron-induced lipid oxidation showed that as oregano oil increased in the diet, malondialdehyde values decreased in tissue samples, suggesting that the oil, particularly at 100 mg/kg of feed, exerted an antioxidant effect on chicken tissues. 4. Dietary α -tocopheryl acetate supplementation at 200 mg/kg of feed displayed greater antioxidant activity than oregano oil at either supplementation rate. 5. Thigh muscle was more susceptible to oxidation than breast muscle, although the former contained α -tocopherol at higher concentration. Muscle α -tocopherol is an important factor influencing lipid oxidation, but the influence of polyunsaturated fatty acids and content of pro-oxidants must be taken into consideration too.

Effect of dietary supplementation with oregano essential oil on performance of broilers after experimental infection with eimeria tenella

A study was carried out to examine the effect of dietary supplementation of oregano essential oil on performance of broiler chickens experimentally infected with Eimeria tenella at 14 days of age. A total of 120 day-old Cobb-500 chicks separated into 4 equal groups with three replicates each, were used in this study. Two groups, one infected with 5·104 sporulated oocysts of E. tenella and the other not, were given a basal diet and served as controls. The other two groups also infected with E. tenella were administered diets supplemented with oregano essential oil at a level of 300 mg/kg, or with the anticoccidial lasalocid at 75 mg/kg. Following this infection, survival rate, bloody diarrhoea and oocysts excretion as well as lesion score were determined. Throughout the experimental period of 42 days, body weight gain and feed intake were recorded weekly, and feed conversion ratios were calculated. Two weeks after the infection with E. tenella supplementation with dietary oregano oil resulted in body weight gains and feed conversion ratios not differing from the non-infected group, but higher than those of the infected control group and lower than those of the lasalocid group. These parameters correspond with the extent of bloody diarrhoea, survival rate, lesion score and oocyst numbers and indicated that oregano essential oil exerted an anticoccidial effect against E. tenella, which was, however, lower than that exhibited by lasalocid.

Functional properties of carotenoids originating from algae

Carotenoids are isoprenoid molecules which are synthesised de novo by photosynthetic plants, fungi and algae and are responsible for the orange, yellow and some red colours of various fruits and vegetables. Carotenoids are lipophilic compounds, some of which act as provitamins A. These compounds can be divided into xanthophylls and carotenes. Many macroalgae and microalgae are rich in carotenoids, where these compounds aid in the absorption of sunlight. Industrially, these carotenoids are used as food pigments (in dairy products, beverages, etc.), as feed additives, in cosmetics and in pharmaceuticals, especially nowadays when there is an increasing demand by consumers for natural products. Production of carotenoids from algae has many advantages compared to other sources; for example, their production is cheap, easy and environmentally friendly; their extraction is easier, with higher yields, and there is no lack of raw materials or limited seasonal variation. Recently, there has been considerable interest in dietary carotenoids with respect to their antioxidant properties and their ability to reduce the incidence of some chronic diseases where free radicals are involved. Possibly, carotenoids protect cells from oxidative stress by quenching singlet oxygen damage with various mechanisms. Therefore, carotenoids derived from algae could be a leading natural resource in the research for potential functional ingredients.

Effect of dietary dried oregano leaves on growth performance, carcase characteristics and serum cholesterol of female early maturing turkeys

1. A study was conducted with 120 female early maturing turkeys to test the effect of dietary dried oregano leaves (Origanum vulgare subsp. hirtum) on body weight (BW), feed intake (FI), feed conversion efficiency (FCE), carcase characteristics and serum cholesterol concentration. Dried oregano leaves had a content of 3·6 ml essential oils/100 g, while the carvacrol content was 855 g/kg of the total essential oils. 2. From 1 to 84 d of age, the turkeys were fed on 4 diets varying in oregano content (OR0, no oregano—control; OR45, 1·25 g oregano/kg; OR90, 2·5 g oregano/kg; OR135, 3·75 g oregano/kg). Birds were given feed and water ad libitum. 3. BW was unaffected by oregano throughout the experiment. FI and FCE were similar among all treatments until 42 d of age. From 43 to 84 d of age and for the overall experimental period, FI decreased linearly in treatment OR135 and FCE increased linearly with dietary oregano content. Body and carcase weights, carcase yield, and the relative weights of the heart and liver were not significantly affected by oregano content. The relative weights of the gizzard and small intestine decreased linearly with oregano content. Serum cholesterol content was similar among all treatments. 4. In the present study, dietary oregano (1·25, 2·5 and 3·75 g/kg) improved FCE in female early maturing turkeys between 43 and 84 d, with the lowest oregano inclusion (1·25 g/kg) giving the most cost effective diet. Thus, dried oregano leaves may be used as a natural herbal growth promoter for early maturing turkeys.

Performance of rabbits and oxidative stability of muscle tissues as affected by dietary supplementation with Oregano essential oil

The effect of dietary supplementation with oregano essential oil on the performance of rabbits, and the susceptibility of the produced raw and thermally treated muscle tissue to lipid oxidation during refrigerated storage, were investigated. A total of 96 weaned rabbits were separated into four equal groups with three subgroups each. One group was given the basal diet and served as control, two groups were administered diets supplemented with oregano essential oil at levels of 100 and 200 mg/kg diet, whereas the remaining group was given a diet supplemented with α-tocopheryl acetate at 200 mg/kg. During the 42-day experimental period, body weight and feed intake were recorded weekly and the feed conversion ratio was calculated. Feeding the experimental diets to rabbits, performance parameters were not affected. Therefore, dietary oregano essential oil exerted no growth-promoting effect on rabbits. With increased supplementation of oregano essential oil, malondialdehyde values decreased in both raw and thermally treated muscles during refrigerated storage. This finding suggests that dietary oregano essential oil exerted a significant antioxidant effect. Dietary supplementation of oregano essential oil at the level of 200 mg/kg was more effective in delaying lipid oxidation compared with the level of 100 mg/kg, but inferior to dietary supplementation of 200 mg α-tocopheryl acetate per kg. This study indirectly provides evidence that antioxidant compounds occurring in oregano essential oil were absorbed by the rabbit and increased the antioxidative capacity of tissues.

Microalgae: a novel ingredient in nutrition

Microalgae are known for centuries, but their commercial large-scale production started a few decades ago. They can be grown in open-culture systems such as lakes or highly controlled close-culture systems, have higher productivity than the traditional crops and can be grown in climatic conditions and regions where other crops cannot be grown, such as desert and coastal areas. The edible microalgae are the green algae (chlorophyta) and the cyanobacteria. Microalgae contain substances of high biological value, such as polyunsaturated fatty acids, proteins, amino acids, pigments, antioxidants, vitamins and minerals. They are promising sources for novel products and applications and they can be used in the diet of humans and animals as natural foods with health benefits. Moreover, they can find use in the protection of the environment, as well as in pharmaceuticals, biofuel production and cosmetics.

An update on approaches to controlling coccidia in poultry using botanical extracts

Abstract 1. This paper reviews the use of botanical extracts in the control of coccidial infection in poultry. 2. Some plants and their respective volatile oils and extracts have the potential to alleviate coccidiosis and reduce its severity. 3. Most plant bioactives improve some, but not all, aspects of coccidiosis with variable effectiveness against different species of Eimeria. 4. Difficulties in comparing research findings have arisen from the use of different experimental models, different active components and infectious dose of Eimeria. 5. Current knowledge of their potential anti-coccidial effects may provide guidance for the use of botanical extracts in the control of the coccidiosis.

Lactic Acid Bacteria as Source of Functional Ingredients

Lactic acid bacteria (LAB) are widespread microorganisms which can be found in any environment rich mainly in carbohydrates, such as plants, fermented foods and the mucosal surfaces of humans, terrestrial and marine animals. In the human and animal bodies, LAB are part of the normal microbiota or microflora, the ecosystem that naturally inhabits the gastrointestinal and genitourinary tracts, which is comprised by a large number of different bacterial species with a diverse amount of strains [1,2].

Innovative Microalgae Pigments as Functional Ingredients in Nutrition

Abstract Pigments derived from microalgae are promising natural sources of high-value compounds. These pigments, which include carotenoids, chlorophylls, and phycobiliproteins, have health-promoting properties such as vitamin precursors, antioxidants, immune enhancers, and anti-inflammatory agents. Accordingly, microalgae pigments can find commercial applications as innovative functional ingredients in the food and feed industries, as well as in pharmaceuticals and cosmetics. Nowadays, consumers are becoming increasingly aware of the correlation between diet, health, and disease prevention; as a result, they prefer these natural substances over synthesized ingredients. Nevertheless, some bottlenecks, such as high production costs and low yields, need to be solved before microalgae pigments can move from niche markets to large-scale use.

The influence of dietary Ascophyllum nodosum on haematologic parameters of dairy cows

The aim of the study was to investigate the effect of Ascophyllum nodosum, an edible brown macroalga, on some haematologic parameters of dairy cows. Nineteen clinically healthy Holstein cows, an average 4.3 years old, were divided into two groups for 49 days. Ten cows received control diet (roughages and concentrate) while the concentrate of 9 cows was additionally supplemented with 80 g A. nodosum/cow/day. Average daily milk production (controls 39.6 kg/cow; A. nodosum 40.2 kg/cow), milk protein and fat were not affected by the alga supplementation. Glucose, sorbitol dehydrogenase, haemoglobin, haematocrit and white/red blood cells were evaluated in weekly blood samples. It was seen that A. nodosum increased blood glucose and decreased sorbitol dehydrogenase compared to controls, without any adverse effects on the other examined parameters. Consequently, A. nodosum may be suggested as a functional ingredient in dairy cow nutrition, improving energy utilization and expressing hepatoprotective effect.