Effect of a commercial essential oil on growth performance, digestive enzyme activity and intestinal microflora population in broiler chickens

Dietary oregano essential oil supplementation improves intestinal functions and alters gut microbiota in late-phase laying hens

BACKGROUND

Dietary essential oil (EO) supplementation can exert favorable effects on gut health in broilers. However, it is unknown whether EO could improve intestinal functions, consequently beneficial for egg performance and quality in late-phase laying hens. This study was aimed to investigate the potential effects of EO on production performance, egg quality, intestinal health and ileal microbiota of hens in the late phase of production. A total of 288 60-week-old Hy-line Brown laying hens were randomly divided into 4 groups and fed a basal diet (control) or basal diets supplemented with oregano EO at 100, 200 and 400 mg/kg (EO100, EO200 and EO400).

RESULTS

Dietary EO supplementation resulted in a quadratic decrease (P < 0.05) in feed conversion ratio with lower (P < 0.05) feed conversion ratio in EO200 group than the control during weeks 9-12 and 1-12 of the trial. Compared to the control, EO addition resulted in higher (P < 0.05) eggshell thickness at the end of week. 4, 8 and 12 and higher (P < 0.05) chymotrypsin activity. There was a quadratic elevation (P < 0.05) in ileal chymotrypsin and lipase activity, along with a linear increase in villus height to crypt depth ratio. Quadratic declines (P < 0.05) in mRNA expression of IL-1β, TNF-α, IFN-γ and TLR-4, concurrent with a linear and quadratic increase (P < 0.05) in ZO-1 expression were identified in the ileum with EO addition. These favorable effects were maximized at medium dosage (200 mg/kg) of EO addition and intestinal microbial composition in the control and EO200 groups were assessed. Dietary EO addition increased (P < 0.05) the abundances of Burkholderiales, Actinobacteria, Bifidobacteriales, Enterococcaceae and Bacillaceae, whereas decreased Shigella abundance in the ileum.

CONCLUSIONS

Dietary EO addition could enhance digestive enzyme activity, improve gut morphology, epithelial barrier functions and modulate mucosal immune status by altering microbial composition, thus favoring feed efficiency and eggshell quality of late-phase laying hens.

Effects of oregano essential oil as an antibiotic growth promoter alternative on growth performance, antioxidant status, and intestinal health of broilers

This experiment was conducted to assess the comparative effects of dietary antibiotics and oregano essential oil (OEO) addition on growth performance, antioxidant status and intestinal health of broilers. A total of 384 one-day-old broilers were randomly allocated to 4 treatments with 6 replicates of 16 broilers each. The 4 treatments were: an antibiotic-free control diet (control), control + 20 mg/kg colistin sulfate and 20 mg/kg virginiamycin (antibiotics), control + 200 mg/kg natural oregano essential oil (NOEO), and control + 200 mg/kg synthetic oregano essential oil (SOEO). The experiment lasted for 42 d. Results showed that birds fed with OEO had greater (P < 0.05) average daily gain (ADG) and lower (P < 0.05) feed conversion ratio (FCR) than those fed with control diet during d 1 to 21. Besides, birds fed with NOEO had the greatest (P < 0.05) ADG in the four groups during d 22 to 42. The serum oxidative stress parameters showed that OEO improved (P < 0.05) the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and glutathione reductase (GR) of birds on day 21 and the activity of total antioxidant capacity (T-AOC) of birds on d 42. Relative to control, NOEO increased (P < 0.05) the activity of T-AOC in jejunum and decreased (P < 0.05) the level of malondialdehyde (MDA) in serum and jejunum. Moreover, OEO supplementation increased (P < 0.05) the concentrations of sIgA in duodenum and jejunum, Lactobacillus and total anaerobes in cecum, as well as activities of trypsin, chymotrypsin, lipase and amylase in duodenum, but restrained (P < 0.05) the amount of Escherichia coli. The NOEO supplementation increased (P < 0.05) total anaerobes of broilers on d 42 and the villus height to crypt depth ratio (VH/CD) of ileum. These results suggest that OEO improved antioxidant status and intestinal health of broilers which contributed to the growth performance improvement of broilers. Dietary OEO supplementation can be a promising alternative to antibiotic growth promoters for improving poultry production.

Mandated restrictions on the use of medically important antibiotics in broiler chicken production in Canada: implications, emerging challenges, and opportunities for bolstering gastrointestinal function and health– A review

Chicken Farmers of Canada has been progressively phasing out prophylactic use of antibiotics in broiler chicken production. Consequently, hatcheries, veterinarians, and nutritionists have been mandated to contend with less reliance on use of preventive antibiotics. A topical concern is the increased risk of proliferation of enteric pathogens leading to poor performance, increased mortality and compromised welfare. Moreover, the gut harbors several taxa such as Campylobacter and Salmonella capable of causing significant illnesses in humans via contaminated poultry products. This has created opportunity for research and development of dietary strategies designed to modulate gastrointestinal environment for enhanced performance and food safety. Albeit with inconsistent responses, literature data suggests that dietary strategies such as feed enzymes, probiotics/prebiotics and phytogenic feed additives can bolster gut health and function in broiler chickens. However, much of the efficacy data was generated at controlled research settings that vary significantly with the complex commercial broiler production operations due to variation in dietary, health and environmental conditions. This review will summarize implications of mandated restrictions on the preventative use of antibiotics and emerging Canadian broiler production programs to meet processor specifications. Challenges and opportunities for integrating alternative dietary strategies in commercial broiler production settings will be highlighted.

Potential role of important nutraceuticals in poultry performance and health - A comprehensive review

Antibiotics use in poultry as a growth promoter leads to the propagation of antibiotic-resistant microorganisms and incorporation of drug residues in foods; therefore, it has been restricted in different countries. There is a global trend to limit the use of antibiotics in the animal products. Prevention of the antibiotics use in the poultry diets led to the reduction in the growth performance. Consequently, there is a high demand for natural substances that lead to the same growth enhancement and beneficially affect poultry health. These constituents play essential roles in regulating the normal physiological functions of animals including the protection from infectious ailments. Nutraceuticals administration resulted beneficial in both infectious and noninfectious diseases. Being the natural components of diet, they are compatible with it and do not pose risks associated with antibiotics or other drugs. Nutraceuticals are categorized as commercial additives obtained from natural products as an alternative feed supplement for the improvement of animal welfare. This group includes enzymes, synbiotics, phytobiotics, organic acids and polyunsaturated fatty acids. In the present review, the summary of various bioactive ingredients that act as nutraceuticals and their mode of action in growth promotion and elevation of the immune system has been presented.

Impact of Ginger Root Powder Dietary Supplement on Productive Performance, Egg Quality, Antioxidant Status and Blood Parameters in Laying Japanese Quails

Medicinal plants with antibacterial effects have been used by humans for centuries. In the recent decade, due to the development of antibiotic resistant strains, many studies have focused on the use of natural compounds as feed additives in livestock. Ginger, among all, have repetitively shown numerous biological activities, antibacterial, and antibiotic properties. This study was conducted to evaluate the effects of ginger root powder (GP) on the performance, egg quality, and blood parameters of Japanese quail. A total of 240 10-weeks old female quails were used in a completely randomized design with 4 treatments, 4 replicates, and 15 birds per replicate. Dietary treatment were basal diet (control) and basal diet containing 0.5, 1, and 1.5 g/kg of ginger root powder. Growth performance and exterior and interior quality of egg were measured biweekly over eight-week period. At the end of experiment blood parameters were evaluated. The results showed that diet supplementation with different levels of GP had no significant effect on egg production, egg mass weight, and egg weight (p > 0.05). However, feed intake and feed conversion ratio were significantly lower in the treatment group than the control in the whole period (p < 0.05). Egg Quality traits (shape index, albumen index, the percentage of albumen, yolk and shell, yolk pH, and shell thickness and strength) were not affected by the supplements in the whole trial period. Addition of GP significantly increased the albumen height, Haugh unit, and albumen pH in comparison with the control treatment (p < 0.05). GP reduced blood triglyceride level yet was ineffective on blood total antioxidant capacity and malondialdehyde. In conclusion, dietary supplementation with GP, could improve productive performance and the egg quality of Japanese quails. Nonetheless a comprehensive study needs to be performed in order to evaluate the impact of quail dietary ginger supplementation on productive performance and egg quality and their stability during storage time for commercial use.

Essential Oils in Livestock: From Health to Food Quality

Using plant essential oils (EOs) contributes to the growing number of natural plants' applications in livestock. Scientific data supporting the efficacy of EOs as anti-inflammatory, antibacterial and antioxidant molecules accumulates over time; however, the cumulative evidence is not always sufficient. EOs antioxidant properties have been investigated mainly from human perspectives. Still, so far, our review is the first to combine the beneficial supporting properties of EOs in a One Health approach and as an animal product quality enhancer, opening new possibilities for their utilization in the livestock and nutrition sectors. We aim to compile the currently available data on the main anti-inflammatory effects of EOs, whether encapsulated or not, with a focus on mammary gland inflammation. We will also review the EOs' antioxidant activities when given in the diet or as a food preservative to counteract oxidative stress. We emphasize EOs' in vitro and in vivo ruminal microbiota and mechanisms of action to promote animal health and performance. Given the concept of DOHaD (Developmental Origin of Health and Diseases), supplementing animals with EOs in early life opens new perspectives in the nutrition sector. However, effective evaluation of the significant safety components is required before extending their use to livestock and veterinary medicine.

Antiparasitic and Antibacterial Functionality of Essential Oils: An Alternative Approach for Sustainable Aquaculture

Using synthetic antibiotics/chemicals for infectious bacterial pathogens and parasitic disease control causes beneficial microbial killing, produces multi-drug resistant pathogens, and residual antibiotic impacts in humans are the major threats to aquaculture sustainability. Applications of herbal products to combat microbial and parasitic diseases are considered as alternative approaches for sustainable aquaculture. Essential oils (EOs) are the secondary metabolites of medicinal plants that possess bioactive compounds like terpens, terpenoids, phenylpropenes, and isothiocyanates with synergistic relationship among these compounds. The hydrophobic compounds of EOs can penetrate the bacterial and parasitic cells and cause cell deformities and organelles dysfunctions. Dietary supplementation of EOs also modulate growth, immunity, and infectious disease resistance in aquatic organisms. Published research reports also demonstrated EOs effectiveness against Ichthyophthirius multifiliis, Gyrodactylus sp., Euclinostomum heterostomum, and other parasites both in vivo and in vitro. Moreover, different infectious fish pathogenic bacteria like Aeromonas salmonicida, Vibrio harveyi, and Streptococcus agalactiae destruction was confirmed by plant originated EOs. However, no research was conducted to confirm the mechanism of action or pathway identification of EOs to combat aquatic parasites and disease-causing microbes. This review aims to explore the effectiveness of EOs against fish parasites and pathogenic bacteria as an environment-friendly phytotherapeutic in the aquaculture industry. Moreover, research gaps and future approaches to use EOs for sustainable aquaculture practice are also postulated.

Efficacy of a phytonutrient supplement at different dietary protein contents on growth performance, gut morphology, digestive enzymes activities and stress indicators of broilers subjected to circular heat stress

Context Dietary manipulations such as reductions in protein or the addition of bioactive feed additives might alleviate the adverse effects of high ambient temperature in poultry. Aims The effects of dietary crude protein (CP) and phytonutrient mixture (PM) on growth performance and physiological responses were evaluated in broilers under circular heat stress (HS). Methods In total, 420 1-day-old broiler chickens were randomly distributed to seven treatments in a factorial arrangement (3 × 2), with three levels of CP (normal, medium (95% of the normal CP content) and low (90% of the normal CP content)) and with or without the addition of PM (mixture of 5 mg/kg carvacrol, 3 mg/kg cinnamaldehyde, and 2 mg/kg capsicum oleoresin). The thermoneutral control (TNC) birds were housed in a thermoneutral chamber and fed with a normal-CP diet without PM supplementation. The other six groups were kept in a HS chamber (33°C) for 8 h (1000 hours to 1800 hours). Key results After 6 weeks, feeding broiler chickens with low-CP diets had adversely affected growth performance and intestinal protease activities, while mortality rate, heterophile to lymphocyte ratio, and serum cortisol concentration of the low-CP group were lower (P &lt; 0.05) than those of the high-CP group. Dietary PM supplementation also positively influenced (P &lt; 0.05) average daily gain, feed conversion ratio, intestinal lipase and trypsin activities and serum T4 concentration. There were the CP × PM interactions (P &lt; 0.05) for jejunal villus height and villus surface area, indicating that the effect of PM on these responses was more marked at the lower dietary CP contents. Conclusions Supplementation with PM can ameliorate the detrimental effects of HS on productive performance and digestive enzyme activities in broilers. The PM supplementation could improve intestinal morphology when applied to the diets of heat-stressed broilers with lower CP contents (95% and 90% of the recommendations). Implications Although growth performance was reduced by feeding low-CP diets (90% of the normal CP content), a beneficial effect was observed on the stress indicators of broilers grown in HS conditions. Dietary supplementation of PM might also be an effective strategy to alleviate the adverse effect of HS.

Essential oils as growth-promoting additives on performance, nutrient digestibility, cecal microbes, and serum metabolites of broiler chickens: a meta-analysis

OBJECTIVE

The purpose of this meta-analysis was to evaluate the effect of dietary essential oils (EOs) on productive performance, nutrient digestibility, and serum metabolite profiles of broiler chickens and to compare their effectiveness as growth-promoting additives against antibiotics.

METHODS

Peer-reviewed articles were retrieved from Web of Science, Science Direct, PubMed, and Google scholar and selected based on pre-determined criteria. A total of 41 articles containing 55 experiments with 163 treatment units were eligible for analyses. Data were subjected to a meta-analysis based on mixed model methodology considering the doses of EOs as fixed effects and the different studies as random effects.

RESULTS

Results showed a linear increase (p<0.001) on body weight gain (BWG) where Antibiotics (FCR) and average daily feed intake decreased (p<0.001) linearly with an increasing dose of EOs. Positive effects were observed on the increased (p<0.01) digestibility of dry matter, crude protein, ether extract, and cecal Lactobacillus while Escherichia coli (E. coli) population in the cecum decreased (p<0.001) linearly. There was a quadratic effect on the weight of gizzard (p<0.01), spleen (p<0.05), bursa of fabricius (p<0.001), and liver (p< 0.10) while carcass, abdominal fat, and pancreas increased (p<0.01) linearly. The dose of EOs linearly increased high density lipoprotein, glucose, protein, and globulin concentrations (p<0.01). In comparison to control and antibiotics, all type of EOs significantly reduced (p<0.001) FCR and tended to increase (p<0.1) BWG and final body weight. Cinnamaldehyde-compound was the only EOs type showing a tendency to increase (p<0.1) carcass weight, albumin, and protein of serum metabolites while this EOs together with EOs-Blend 1 decreased (p<0.01) E. coli population. Low density lipoprotein concentration decreased (p<0.05) with antibiotics and carvacrol-based compound when compared to the control group.

CONCLUSION

This evidence confirms that EOs are suitable to be used as growth promoters and their economical benefit appears to be promising.

Productive parameters, cecal microflora, nutrient digestibility, antioxidant status, and thigh muscle fatty acid profile in broiler chickens fed with Eucalyptus globulus essential oil

This study was conducted to evaluate the effects of different dietary inclusion of eucalyptus essential oil (EEO) on growth performance, relative organ weight, cecal microflora, nutrient digestibility, serum biochemical parameters, and thigh muscle fatty acid profile in broiler chickens. A total of six hundred 1-day-old male broiler chickens were randomly allocated into 5 treatment groups with 8 replicate pens, and each pen contained 15 birds. The experiment lasted for 42 d. Dietary treatments included corn–soybean meal-based diet supplemented with 0, 250, 500, 750, and 1,000 mg/kg EEO. The results indicated that dietary treatments had no effect on growth performance parameters in the 1 to 10 d period. From day 11 to 24, dietary supplementation of EEO showed a linear decrease in feed conversion ratio (FCR, P < 0.05). From day 25 to 42 and the overall period (1–42 d), broilers fed with different levels of EEO showed a linear increase in body weight gain (BWG) and reduction in feed conversion ratio (linear, P < 0.05). The relative organ weight were unaffected by any of the dietary treatments. With increasing levels of EEO, the cecal Escherichia coli (linear, P = 0.085) count showed a trend in reduction, and the cecal lactic acid bacteria population tended to increase (linear, P = 0.063). The apparent ileal digestibility of ether extract and organic matter were linearly and quadratically increased in response to increasing dietary EEO supplementation (P < 0.05). A trend of linear decrease in total cholesterol in the serum of birds fed with different levels of EEO was recorded (P = 0.074). Eucalyptus essential oil's inclusion increased serum superoxide dismutase linearly but reduced serum malondialdehyde linearly (P < 0.05). Dietary supplementation of EEO affected the fatty acid profile of thigh muscle so that increased the concentrations of total polyunsaturated fatty acids (linear, P < 0.05) and reduced total saturated fatty acid contents (linear, P < 0.05). Taken together, the inclusion of EEO increased BWG and decreased FCR during day 25 to 42 and day 1 to 42, and partially improved cecal microflora balance, nutrient digestibility, antioxidant activity, and thigh muscle fatty acid profile in broiler chickens.

The effects of clove seed (Syzygium aromaticum) dietary administration on carcass characteristics, meat quality, and sensory attributes of broiler chickens

Previous studies have shown positive outcomes associated with the incorporation of cloves into broiler chicken diets. This study aimed to evaluate carcass characteristics, meat quality, and sensory attributes of broiler chickens fed diets supplemented with different clove seed levels. A total of 240 day-old Ross 308 broiler chicks were fed 1 of seven dietary treatments. The control group diet contained 0% clove seeds, whereas the treatment group diets contained up to 6% clove seeds. The chickens' final BW was significantly different between the treatments, which decreased linearly with increasing levels of clove seed inclusion. Broiler chickens fortified with clove seeds did not significantly affect the chickens' carcass characteristics and body composition. However, an increment in weights of carcass components (liver, heart, and gizzard) was observed in low clove seed levels. In addition, water-holding capacity, cooking loss percentages, and tenderness of the meat were improved owing to clove seed inclusion (1 or 2%) compared with the control group. Further studies are warranted to optimize the outstanding use of cloves toward broiler chicken performance enhancement and to produce a high quality of meat.

Evaluation of Achyranthes japonica Nakai extract on growth performance, nutrient utilization, cecal microbiota, excreta noxious gas emission, and meat quality in broilers fed corn-wheat-soybean meal diet

This study was conducted to investigate the effects of dietary supplementation of Achyranthes japonica Nakai (AJN) extract as a natural feed additive on growth performance, nutrient utilization, cecal microbiota, excreta noxious gas emission, and meat quality in broilers fed corn-wheat-soybean meal diet. In total, seven hundred twenty 1-day-old male Ross 308 broilers with an average body weight (BW) of 43.36 ± 1.42 g were used in a 35-d feeding trial. Broilers were randomly assigned to 1 of the 4 treatments. Each treatment had 10 replication pens with 18 birds per replication. Dietary treatments composed of corn-wheat-soybean meal-based diets along with the addition of 0, 0.025, 0.05, and 0.1% of AJN extract. The BW gain and feed conversion rate were linearly influenced (P < 0.05) by the supplementation of AJN extract during days 8 to 21, 22 to 35, and the overall experiment. At the end of the experiment, the digestibility of dry matter and nitrogen and the population of cecal lactic acid bacteria were linearly improved (P < 0.05) in response to increasing AJN extract supplementation. Excreta emission of ammonia showed a linear decrease (P < 0.05) with the increasing levels of AJN extract. The breast muscle percentage linearly increased (P < 0.05) in birds fed AJN extract contained diets. In summary, the inclusion of AJN extract in corn-wheat-soybean meal diet improved growth performance, nutrient utilization, intestinal microbiota balance, and breast meat production and decreased excreta ammonia emission, which confirmed the applicability of AJN extract as a natural feed additive in broilers.

Avian Pathogenic Escherichia coli and Clostridium perfringens: Challenges in No Antibiotics Ever Broiler Production and Potential Solutions

United States is the largest producer and the second largest exporter of broiler meat in the world. In the US, broiler production is largely converting to antibiotic-free programs which has caused an increase in morbidity and mortality within broiler farms. Escherichia coli and Clostridium perfringens are two important pathogenic bacteria readily found in the broiler environment and result in annual billion-dollar losses from colibacillosis, gangrenous dermatitis, and necrotic enteritis. The broiler industry is in search of non-antibiotic alternatives including novel vaccines, prebiotics, probiotics, and housing management strategies to mitigate production losses due to these diseases. This review provides an overview of the broiler industry and antibiotic free production, current challenges, and emerging research on antibiotic alternatives to reduce pathogenic microbial presence and improve bird health.

Probiotic fermented feed improved the production, health and nutrient utilisation of yellow-feathered broilers reared in high altitude in Tibet

1. Probiotic fermented feed (PFF) has been widely used in poultry production. The current study was designed to investigate whether PPF could alleviate the negative effects of hypoxia on yellow-feathered broilers reared at high altitude on the Tibet Plateau. 2. A total of 480, one-day-old male Lingnan yellow-feathered broilers were divided into four treatment groups with six replicates, each containing 20 broiler chickens. Broilers in the four groups were offered either a basal diet (without antibiotics) or test diets containing 5, 10 and 15% of PFF respectively. The experiment lasted for eight weeks. 3. Birds fed the 10% PFF diet exhibited increased (P < 0.05) average daily gain (ADG) on d 28 and 56, body weight (BW) on d 56, total tract apparent digestibility (TTAD) of dry matter (DM), crude protein (CP) and gross energy (GE). Feeding diets supplemented with 10% PFF increased (P < 0.05) digestive activity and gut development in duodenum and jejunum. Supplementation with 10% or 15% PFF significantly increased (P < 0.05) the caecal populations of Lactobacilli and Bifidobacteria spp. and decreased (P < 0.05) caecal E. coli and Salmonella spp. on d 28 and 56. 4. The ADG and BW on d 56, protease activity in duodenum on d 56 and jejunum on d 28 and 56, villus height and villi absorptive area in duodenum and jejunum and caecal Bifidobacteria spp. showed a quadratic (P < 0.05) dose response as supplemental PFF level increased. The TTAD of DM and CP and caecal Lactobacilli spp. increased linearly with PFF level. The caecal populations of E. coli and Salmonella spp. decreased linearly with PFF level. 5. In conclusion, addition of PFF in broiler diets had the potential to improve production performance, nutrient utilisation, intestinal digestive function and caecal microflora in yellow broiler chickens raised at high altitude.

Effects of dietary supplementation with herbal extract mixture on growth performance, organ weight and intestinal morphology in weaning piglets

BACKGROUND

Many countries are increasingly prohibiting the addition of antibiotics in livestock diets. Therefore, herb extracts have gradually drawn attention to substitute antibiotics. Our present study aimed to determine the effects of herbal extract mixture (HEM) in dietary on growth performance, organ weight, intestinal morphology and intestinal nutrient transporters in weaned pigs.

METHODS

27 piglets (Duroc × [Landrace × Yorkshire]; Body Weight (BW) = 5.99 ± 0.13 kg) were weaned at day 21 and randomly divided into three groups (n = 9 piglets/group). All piglets received a basal diet containing similar amounts of nutrients for 14 days. The three groups were the control (no additive), the antibiotics (375 mg/kg chlortetracycline, 20%, 500 mg/kg enramycin, 4%, 1,500 mg/kg oxytetracycline calcium, 50%) and the HEM group (1000 mg/kg extract mixture of golden-and-silver honeysuckle, huangqi, duzhong leaves and dangshen). After 14 d of treatment, we collected tissue samples to measure organ weight, intestinal parameters, intestinal morphology, digestive enzyme activities and intestinal mRNA expression of nutrient transporters.

RESULTS

The HEM group had no effects on growth performance and organ weight of weaned pigs. But compared with the control group, both HEM and antibiotics improved intestinal morphology, and HEM elevated the expression of nutrient transporters in ileum (SLC6A9, SLC15A1, and SLC5A1). HEM significantly decreased the activities of maltase in ileum and the ratio of small intestinal weight to BW than control group.

CONCLUSIONS

These results indicate benefit effects of the supplementation of HEM in diet, including modulating intestinal morphology and increasing the mRNA expression of nutrients transporters. These findings suggest that HEM provides novel insights into a variety of herbal extract mixtures to replace antibiotics in animal production.

Effects of phytobiotic feed additives on growth traits, blood biochemistry, and meat characteristics of broiler chickens exposed to Salmonella typhimurium

Because of concerns over the use of antibiotics in poultry feed, this study was designed to determine the effectiveness of phytobiotic supplementation as an alternative to antibiotic use based on growth performance and meat characteristics of broilers exposed to Salmonella typhimurium. The effects of an antibiotic and 3 phytobiotic feed additives (PFA), Mix-Oil Mint (MO_mint), Mix-Oil Liquid (MO_liq), and Sangrovit Extra (Sang_ext), were compared. At day of age, 280 Ross chicks were randomly allocated into 6 treatments. At 15 d, all chicks except negative control were exposed to S. typhimurium. The offered 6 diets were as follows: T1, negative control; T2, infected with S. typhimurium; T3, infected + avilamycin (0.1 g/kg); T4, infected + MO_mint (0.2 g/kg); T5, infected + plant extract in liquid form MO_liq (0.25 mL/L); and T6, infected + Sang_ext (0.15 g/kg). During the cumulative starter period, PFA improved performance over that of the control, and the food conversion ratio (FCR) was lower for T3 and T5 compared with T1 (P < 0.05). During the cumulative finisher period (15–35 d), a lower body weight gain (P < 0.01) was observed in T2. T1 had the best FCR and production efficiency factor, but they were not significantly different from those of T3, T4, and T6 (P < 0.001). At 35 d, T1 and T4 had a higher breast percentage as compared with those of T2 (P < 0.05). Blood glucose decreased significantly (P > 0.05) in T2 and T5 compared with that in T1 and T4. Alanine transaminase concentration decreased significantly (P < 0.01) in T4 and T5 compared with that in T1, T2, and T3. Treatments had significant effects on breast temperature and pH (P < 0.001). A significant decrease in the myofibril fragmentation index occurred in T1 and T6. Hardness and chewiness were influenced by treatments (P < 0.05). In conclusion, dietary supplementation with PFA could effectively compare with that of antibiotic avilamycin in the maintenance of growth performance and improvement in meat characteristics of broilers challenged with S. typhimurium.

Effect of essential oils or saponins alone or in combination on productive performance, intestinal morphology and digestive enzymes' activity of broiler chickens

This study was carried out to evaluate the effect of essential oils or saponins alone or in combination on productive performance, intestinal morphology, and digestive enzymes' activity in broilers. Four hundred one-day-old male broiler chickens were randomly assigned to four treatments, each with 5 replicates. The birds were fed experimental diets contained either no phytogenic feed additives (control) or were supplemented with 25.0 mg/kg of an essential oil blend from star anise, rosemary, thyme and oregano (essential oils); 46.0 mg/kg of a Quillaja saponin blend (saponins); or a combination of both phytogenic preparations (essential oils plus saponins). The experiment lasted for 42 days. Body weight, feed intake and weight gain were recorded weekly, and the feed conversion ratio was calculated, throughout the experiment. Intestinal morphology and digestive enzymes' activity were determined at the end of the experiment. It was found that the body weight was increased by all dietary supplements at the end of the experiment. There was no change in performance parameters among the treatments during the starter period. At the grower period and the overall experiment, the weight gain of birds was higher in all supplemented groups compared to the control, but the feed conversion was better in the essential oils with saponins treatment. Supplementation of essential oils or saponins alone or in combination increased the villus height and the villus/crypt ratio of the intestine. There was an increase in trypsin, chymotrypsin and elastase activities in the essential oils plus saponins group only. The obtained results indicate that the phytogenic feed additives, especially essential oils with saponins, can be considered as new promising agents in promoting the growth performance of broilers. The effect could be related to its improving impact in intestinal development and increasing the protease enzymes' activity, resulting in increased protein digestibility and absorption of dietary nutrients.

Lippia gracilis Schauer essential oil as a growth promoter for Japanese quail

The use of antibiotics as performance enhancers in animal feeding is declining, so Lippia gracilis Schauer essential oil (LGSEO) could be used as a potential substitute for the conventionally used growth promoters. The LGSEO contains components such as carvacrol and thymol, which kill and/or control pathogenic bacteria, increase population of beneficial organisms, act against oxidative processes and onto nutrient digestibility and absorption. The aim of this study was to investigate the action and the effects of LGSEO as a growth promoter in the diet of Japanese quail by examining their productive performance, intestinal microbiology, blood biochemical parameters, hepatic thiobarbituric acid reactive substances (TBARS) content and intestinal gene expression. A total of 252 two-day-old quail (Coturnix coturnix japonica) were assigned to 3 treatments in 7 replicates, using 12 birds per experimental unit. The treatments consisted of a basal diet, basal diet + LGSEO at 400 mg/kg of diet and basal diet + chemical antimicrobial (bacitracin methylene disalicylate) at 500 mg/kg of diet. The experimental period was 34 days. The highest feed intake (P < 0.01) was found in the group receiving the conventional antimicrobial, whereas the best feed conversion (P < 0.01) was shown by the animals receiving LGSEO. Escherichia coli growth was restricted in the quail receiving the growth promoters. Salmonella spp. growth was controlled by the treatment containing the conventional antimicrobial. There was no difference between the treatments (P > 0.05) for the concentration of aspartate aminotransferase and alanine aminotransferase enzymes in the blood or hepatic TBARS content. Birds receiving negative-control treatment exhibited a higher expression of sodium-glucose cotransporter (SGLT1), while those receiving the treatment with essential oil showed lower catalase (CAT) and glutathione peroxidase (GPX7) expressions compared to the conventional antimicrobial and control groups, respectively. Lippia gracilis Schauer essential oil is a powerful performance enhancer for Japanese quail by virtue of its abilities to improve their intestinal environment, balance the microbial population and reduce energy expenditure for oxidative processes.

The Effects of Different Oil Sources on Performance, Digestive Enzymes, Carcass Traits, Biochemical, Immunological, Antioxidant, and Morphometric Responses of Broiler Chicks

This research evaluate the influence of different oil sources, namely fish oil (FO), coconut oil (CocO), canola oil (CanO), or a mixture of the three oils (MTO)—included at 1.5% in broiler diets—compared to a no oil-supplemented diet. Hence, 250 unsexed, 1-day-old Cobb chicks were weighed and randomly allocated into five dietary treatment groups of 50 chicks each and five replicates per group. Oil-supplemented diets significantly increased the growth, improved the feed conversion ratio (FCR), and decreased the abdominal fat percentage compared to the control diet. Amylase was significantly elevated due to feeding the FO- or CocO-supplemented-diet compared to the control diet, whereas lipase increased due to offering CocO- and CanO-enriched diet; chymotrypsin increased due to different oil sources. High-density lipoprotein cholesterol (HDL-C) increased markedly due to offering an oil-supplemented diet, but low-density lipoprotein cholesterol (LDL-C), the LDL-C:HDL-C ratio, and malondialdehyde (MDA) decreased. Blood plasma immunoglobulin (Ig) G and IgM significantly increased due to feeding CocO, CanO, or MTO compared to the control group, whereas FO increased IgG only. FO- and CanO-containing diets resulted in the highest increase in α2-globulin and γ-globulin. The antibody titer to avian influenza (HIAI) and Newcastle disease (HIND) were significantly elevated due to CocO supplementation compared to the control group. The bursa follicle length and width and thymus cortex depth were increased considerably due to the FO-supplemented diet compared to the control, but the follicle length:width ratio decreased. The villus height:depth ratio was significantly elevated due to both the CanO and MTO diets. The antioxidant status improved considerably due to the addition of CocO and CanO. Both CanO and MTO similarly increased plasma T3, T4, and the T3:T4 ratio. In conclusion, oil supplementations at 1.5% enhanced growth performance and immune status, improved the blood lipid profile and antioxidants status, and the effect of the oil sources depends on the criteria of response.

Effects of encapsulated essential oils and organic acids on laying performance, egg quality, intestinal morphology, barrier function, and microflora count of hens during the early laying period

The objective of this study was to investigate the effect of encapsulated essential oils and organic acids (EOA) on the growth performance, egg quality, intestinal morphology and functions, and microbial count of laying hens from week 21 to 30. A total of five hundred and four 21-wk-old layers were randomly allotted into 4 groups consisting of 7 replicates with 18 birds per replicate. The birds were fed a basic diet (CON) or diets with EOA at 150 mg/kg, 300 mg/kg, and 450 mg/kg in the other 3 groups, respectively. Compared to the CON group, the addition of 150 mg/kg EOA significantly increased laying rate (P < 0.05) of hens from week 21 to 25. A linear increasing (linear, P < 0.01) in ileal villus height of laying hens fed EOA from 150 to 300 mg/kg was observed at week 30. At week 25, the supplementation of 300 mg/kg EOA significantly increased (P < 0.05) mRNA relative expression of aminopeptidase, sodium-glucose cotransporter 1, and Na+-independent neutral amino acid transporter in duodenum and glucose transporter 2 in jejunum of laying hens compared to the CON groups. Meanwhile, the relative expression of glucose transporter 2 mRNA in the jejunum was upregulated with increasing concentration of EOA in diets (linear, P < 0.05). Hens in EOA 300 group had higher mRNA relative expression of mucin-2 in ileum (P < 0.05) than hens in CON group. Additionally, the secretory immunoglobulin in ileum A were linear decreased (linear, P < 0.01) with the increasing supplement of EOA. Dietary supplementation with EOA tended to increase (P = 0.083) the counts of Bifidobacterium in cecal digesta at week 25 and 30. In conclusion, dietary with EOA may maintain intestinal tract morphology and promote digestive and absorptive capacities and barrier function, especially at 300 mg/kg. This study provided evidence of using EOA as a potential feed additive for laying hens.

Effects of incubation and chick rearing on intestinal morphology, digestive enzyme activities, and mRNA expression of nutrient transporter genes in the pigeon (Columba livia) under artificial farming conditions

The present study investigated the changes in morphology, enzyme activities in the pancreas and mucosa, and nutrient transporter gene expression in the duodenum and jejunum in male and female pigeons during the incubation and chick-rearing periods. Forty-two pairs of White King pigeons with 2 fertile eggs per pair were randomly divided into 7 groups by different breeding stages. The crypt depth of the duodenum and jejunum reached the peak at day 1 (R1) and day 7 (R7) of chick rearing, respectively. The jejunum surface area increased to a maximum value at R1. Amylase activity in the pancreas decreased to the lowest value at R1, whereas trypsin and lipase activities peaked at 17 D of incubation (I17) and R7, respectively. In male pigeons, mucosal Na⁺-K⁺-ATPase activity in the duodenum and jejunum was the highest at R15 and it was at I17 in female pigeons. Jejunum sucrose activity in female pigeons was higher at I4 than that at I17 (P < 0.05). The gene expression of FAT/CD36 and I-FABP in the duodenum gradually increased and then declined in the late chick-rearing period. SGLT1 in the jejunum decreased to a lower level at I17 and R25 in male pigeons (P < 0.05). GLUT2 expression in female duodenum and male jejunum decreased to a lower value at I17 compared with that at R15 (P < 0.05). In the late of incubation (from I10 to I17), expression of duodenum CAT1, B⁰AT1, and PepT1 and jejunum CAT1, ASCT1, and PepT1 in female pigeons was significantly reduced (P < 0.05), whereas opposite results were found in male jejunum CAT1 and duodenum ASCT1. In conclusion, variations of intestinal morphology, activities of pancreatic and mucosal enzymes, and gene expression of nutrient transporters during incubation and chick-rearing periods, underlying potential changes of digestive and absorptive function and intestinal adaptation with sexual effects, may represent a complicated response to stimuli of different breeding stages.

Dietary encapsulated essential oils and organic acids mixture improves gut health in broiler chickens challenged with necrotic enteritis

Background

The poultry industry is in need of effective antibiotic alternatives to control outbreaks of necrotic enteritis (NE) due to Clostridium perfringens. In the present study, we investigated the effects of dietary supplementation with a blend of encapsulated essential oils and organic acids (BLJ) on growth performance and gut health using a coinfection model of NE in broiler chickens.

Methods

Two hundred and eighty-eight one-day-old male Arbor Acres broiler chicks were randomly assigned using a 2 × 2 factorial design into two groups fed either 0 or 500 mg/kg dietary BLJ and co-challenged (or not challenged for the control) with Eimeria spp./C. perfringens.

Results

Infected birds fed the BLJ-supplemented diet exhibited an improved feed conversion ratio throughout the trial (P < 0.01), a higher villus height and villus height/crypt depth ratio, and reduced intestinal C. perfringens counts, liver C. perfringens carriage, gut lesion scores and serum fluorescein isothiocyanate dextran (FITC-D) concentrations at 7 d post-infection compared with those of birds without BLJ supplementation (P < 0.05). NE-infected birds fed BLJ exhibited significantly upregulated claudin-1 and IGF-2 mRNA levels (P < 0.05), increased A20 mRNA expression and significantly downregulated TRAF-6, TNFSF15 and TOLLIP mRNA levels in the jejunum at 7 d post-infection compared with those in birds without BLJ supplementation (P < 0.05). Compared with the uninfected and untreated birds, the uninfected birds fed BLJ displayed increased relative abundances of Lactobacillus and Coprococcus but reduced Rikenellaceae levels. Compared with the unsupplemented NE-challenged birds, infected birds fed BLJ showed an increased relative abundance of Unclassified_Lachnospiraceae and a significantly decreased relative abundance of Erysipelotrichaceae.

Conclusion

BLJ supplementation improved growth performance and gut health in NE-infected broiler chickens by strengthening the intestinal barrier function, positively modulating the gut microbiota community and differentially regulating intestinal immune responses. Our results also suggested that adding BLJ effectively controlled NE infections after experimental Eimeria and Clostridium perfringens coinfection.

Effects of Thymol and Thymol α-D-Glucopyranoside on Intestinal Function and Microbiota of Weaned Pigs

The present study evaluated gluco-conjugation as a measure to delay thymol absorption and enhance its antimicrobial activity in the gut of weaned piglets. The three dietary treatments consisted of a basal diet without additives (TCON), supplemented with thymol at 3.7 mmol/kg dry matter (TTHY), or with an equimolar amount of thymol α-D-glucopyranoside (TTαG). Each dietary treatment was replicated in 6 pens with 2 piglets per pen (n = 12 for analytical parameters) and was supplemented for 14 days. The total (free plus gluco-conjugated) thymol concentrations in the stomach contents were 14% lower in TTαG as compared to TTHY piglets. Neither of the additives could be detected further down the gut. E.coli counts in the proximal small intestine were significantly lower in TTHY than in TTαG pigs (3.35 vs. 4.29 log10 CFU/g); however, other bacterial counts and their metabolites were unaffected by treatment. A metagenomic bacterial analysis revealed a great relative abundance of Lactobacillus spp. in the distal small intestine (range 88.4%-99.9%), irrespective of treatment. The intestinal barrier function was improved by TTHY, but not TTαG, compared to TCON. In conclusion, gluco-conjugation did not result in higher thymol concentrations in the gut, but conversely, it seemed to diminish the biological effects of thymol in vivo.

Thymol efficacy against coccidiosis in pigeon (Columba livia domestica)

Investigation of thymol efficacy to control pigeon coccidiosis was performed using in-vitro and in-vivo studies. The in-vitro experiment was conducted by treatment of unsporulated oocysts of Eimeria species of pigeon by five concentrations (0.625-10%) from either thymol, eucalyptus essential oil or amprolium anticoccidial drug and incubation for 72 h. The in-vitro study revealed that thymol concentrations ≥1.25 % caused significant deformity on sporulated and unsporulated oocysts compared to the other two products. Eucalyptus oil was active at both 5 and 10 % concentrations on unsporulated oocysts but showed non-significant changes on sporulated ones at all tested concentration. Meanwhile, in-vivo testing of thymol was conducted using 45 squabs which were equally divided into three groups; untreated uninfected (UU) negative control, untreated infected (UI) positive control and thymol treated (TT). TT group received 40 mg/kg BWt thymol in feed for 15 days. At day five post thymol supplementation, the UI and TT groups were orally infected by 25 × 10³sporulated oocysts of pigeon Eimeria labbeana. The in-vivo study showed that thymol minimized the adverse effect of Eimeria infection in pigeon as observed by less severity of clinical signs, low oocysts count and improvement of body weight when compared with untreated infected birds. In addition, the biochemical parameters including liver and kidney functions tests proved thymol safety in pigeon. Moreover, thymol showed excellent antioxidant activity that was estimated by significantly lower value of malondialdehyde in TT than UI groups. The histopathological findings of TT group showed intact intestinal villi with mild sloughed epithelium, degenerated coccidian developmental stages and massive infiltrations of mononuclear cells in lamina propria. In conclusion, thymol can be safely used to control pigeon coccidiosis as a natural effective compound.

Effect of Housing System and Rosemary and Cinnamon Essential Oils on Layers Performance, Egg Quality, Haematological Traits, Blood Chemistry, Immunity, and Antioxidant

Simple Summary

The current study aimed to investigate the effects of a housing system, and dietary supplementation of rosemary and cinnamon essential oils on layers performance and egg quality. A factorial arrangement (2 × 3) was performed including two housing systems (floor and cage) and three different types of essential oils (0, 300 mg/kg diet of rosemary and 300 mg/kg diet of cinnamon essential oils) to study their effects on the productive performance, egg quality, immunity, oxidative stress and haematology of laying hens during the production stages. The data suggested that the supplementation of rosemary and cinnamon essential oils in laying hen diet showed significant positive effects on hen performance and egg production. Additionally, the different housing systems did not result in any positive or negative impact on these traits.

Abstract

Housing system and nutrition are non-genetic factors that can improve the well-being of animals to obtain higher quality products. A better understanding of how different housing systems and essential oils can influence the performance of layers is very important at the research and commercial levels. The current study aimed to investigate the effects of a housing system and dietary supplementation of rosemary and cinnamon essential oils on layers’ performance and egg quality. A factorial arrangement (2 × 3) was performed include two housing systems (floor and cage) and three different types of essential oils (0, 300 mg/kg diet of rosemary and 300 mg/kg diet of cinnamon essential oils) to study their effects on the productive performance, egg quality, immunity, oxidative stress and haematology of ISA brown laying hens during the production stages (from 28 to 76 weeks of age). Birds were randomly divided into two groups each comprising of 1500 birds; the first group was moved from the litter to reared laying cages while the second group was floor reared. Each group was randomly divided into three groups, the first was considered as a control group, the second treated with rosemary essential oil, and the third with cinnamon essential oil. The differences in egg production and weight, egg quality, feed intake and conversion, blood picture and chemistry, immunity, and antioxidant parameters between the different housing systems (floor and cage) were not significant at (p < 0.05 or 0.01). On the other hand, the egg production and weight, Haugh unit, feed intake and conversion, blood cholesterol, Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), urea, Ca, P, immunity, and antioxidant parameters were significantly (p < 0.05 or 0.01) better in rosemary and cinnamon groups than in the control group. Furthermore, the results of dietary supplementation with rosemary and cinnamon were very close. Regarding egg production and weight, there were no significant differences due to the interactions. The differences in egg mass among the interactions were also not significant except at 68–76 weeks, where the cage × cinnamon group was the highest. Under the floor rearing system, birds that were fed a diet supplemented with or without essential oils (EOs) consumed more feed than those raised under the cage system. Regarding feed conversion rate (FCR), the differences among the interactions were not significant except at 44–52, 52–60 and 68–76 weeks, where the cage × cinnamon group was the lowest. Excluding glutathione peroxidase (GPx) activity (p < 0.001), all immunity and antioxidant indices were not statistically different as a consequence of the interaction among EOs and housing systems. Additionally, the highest levels of phosphorus were observed for layers fed diets enriched with cinnamon oil with the cage or floor system. In conclusion, the data suggested that supplementation of rosemary and cinnamon essential oils in laying hen diet showed significantly positive effects on hen performance and egg production. Cholesterol, liver and kidney functions, immunity, and antioxidant parameters improved with rosemary and cinnamon supplementation when compared to the control. Additionally, the different housing systems did not result in any positive or negative impact on these traits.

Effect of dietary pomegranate by-product extract supplementation on growth performance, digestibility, and antioxidant status of growing rabbit

The study objective was to investigate the effect of three levels of dietary pomegranate by-product extract (PBE) (100, 150, and 200 mg) on growth performance, nutrient digestibility, carcass characteristics, and some blood parameters. Sixty weaned New Zealand White (NZW) rabbits at 5 weeks of age with an average body weight 561.67 ± 6.68 g were randomly allotted to four dietary groups; each group included three replicates (five rabbits each). The control group was fed a basal diet without PBE; the other three experimental groups fed diets supplemented with PBE at 100-, 150-, and 200-mg/kg diet. The results revealed that dietary supplementation of PBE at each level significantly (P < 0.05) improved the average final body weight and FCR. Rabbits group fed diet supplemented with 200 PBE recorded the highest (P < 0.05) of all nutrients digestibility, DCP, TDN, and DE. Feeding rabbits on diets supplemented with PBE at levels 100-, 150-, and 200-mg/kg diet increased (P < 0.05) plasma concentrations total protein, albumin, globulin, HDL, TAC, SOD, and GSH-Px, compared to the control group. The opposite trend was noticed with glucose, total lipids, triglycerides, total cholesterol, and LDL concentrations whereas they were lower (P < 0.05) than those of the control group. The obtained results also showed that PBE supplementation levels reduced (P < 0.05) both E. coli and salmonella counts in rabbit cecum. It could be concluded that the supplementation of rabbit diets with PBE at 100-, 150-, and 200-mg/kg diet improved growth performance and the nutrient digestibility. Moreover, PBE had an antioxidant and antibacterial effect of the growing rabbits.

Effects of dietary Achyranthes japonica extract supplementation on the growth performance, total tract digestibility, cecal microflora, excreta noxious gas emission, and meat quality of broiler chickens

The present study was investigated the effects of dietary Achyranthes japonica extract (AJE) supplementation on the growth performance, total tract digestibility, cecal microflora, excreta noxious gas emission, breast meat quality, and organ weight in broiler chickens. In total, 640 Ross × Ross male broiler chickens (1-day-old) were randomly distributed into 4 dietary treatments with 10 replicate cages (16 birds/replicate) per treatment group for 5 wk. The dietary treatments included a control basal diet without AJE, and diets with 0.025, 0.05, or 0.1% AJE. Body weight gain, feed intake, and feed conversion improved linearly with the supplementation of AJE over the experimental period (days 1 to 35) (P < 0.05). Dietary AJE supplementation caused a significant increase in the apparent total tract digestibility of dry matter and nitrogen (linear, P < 0.05). The cecal Lactobacillus, E. coli, and Salmonella counts were linearly affected with increasing dietary AJE supplementation (P < 0.05). With increasing levels of AJE, excreta ammonia gas concentration showed a linear decrease (P < 0.05). The breast muscle weight linearly increased, along with a decrease in the abdominal fat weight, in treatment groups fed with AJE (P < 0.05). These results indicate that dietary addition with increasing AJE linearly improved growth performance, total tract digestibility, cecal microflora, excreta ammonia gas emission, and abdominal fat weight in broiler chickens.

Effects of dietary Lycium barbarum polysaccharides on growth performance, digestive enzyme activities, antioxidant status, and immunity of broiler chickens

Lycium barbarum polysaccharides (LBP) are considered to be the major bioactive components of L. barbarum and have been widely used as a well-known traditional Chinese medicine and functional food because of their various biological activities. However, no published research has investigated the use of LBP as a feed additive in broilers. The objective of this study was to evaluate the effects of dietary LBP supplementation on the growth performance, digestive enzyme activities, antioxidant status, and immunity of broiler chickens. A total of 256 one-day-old Arbor Acres male broiler chicks were randomly allotted into 4 groups, with 8 replicates of 8 birds each, and were fed a corn-soybean meal-type basal diet supplemented without (control group) or with 1,000, 2,000, or 4,000 mg/kg LBP for 6 wk. The results showed that compared with the control diet, a significant increase in ADG (P < 0.05) during the grower and overall periods was observed in chickens fed the basal diet supplemented with 2,000 mg/kg LBP, whereas supplementation with 1,000 or 2,000 mg/kg LBP decreased feed-to-gain ratio (P < 0.05) during the starter period. The inclusion of LBP in the broiler diets increased overall amylase, lipase, and protease activities (P < 0.05). Supplementation with increasing levels of dietary LBP increased the activities of superoxide dismutase and glutathione peroxidase but decreased malondialdehyde content in the serum and liver (P < 0.05). Broilers fed with LBP-containing diets exhibited higher serum IgG and IgA concentrations (P < 0.05) than the broilers fed with the control diet. Serum tumor necrosis factor α and IL-4 concentrations were significantly elevated in the group fed 2,000 mg/kg LBP compared with the control group (P < 0.05). Broilers fed diets supplemented with LBP showed linear (P < 0.05) and quadratic (P < 0.05) increases in serum IL-6 and interferon gamma concentrations. The results indicated that dietary LBP supplementation can improve growth performance, digestive enzyme activities, antioxidant capacity, and immune function of broilers. In conclusion, LBP may be used as a promising feed additive for broilers, and a supplementation level of 2,000 mg/kg LBP in the broiler diet is recommended.

Influence of dietary plant fats and antioxidant supplementations on performance, apparent metabolizable energy and protein digestibility, lipid oxidation and fatty acid composition of meat in broiler chicken

This study aimed to evaluate the effects of dietary different antioxidants and plant oils on performance, apparent metabolizable energy and protein digestibility, meat quality and meat fatty acid composition of broiler chickens. In all, 480 male broiler chicks of 1‐day old were assigned in a completely randomized design with factorial arrangement 2 × 5 (plant oil sources [soybean and rapeseed oils] and antioxidant sources [vitamin E, Thyme, Rosemary and Satureja essential oils] furthermore control treatment without antioxidant). The results indicated that at 1–42 d of age, growth performance and carcass yield of birds were not influenced by dietary plant oils and antioxidant supplementations. Dietary Thyme essential oil (300 mg/kg) resulted in an increase in crude protein digestibility and birds fed on diets without antioxidant showed increase in the apparent metabolizable energy (p < .01). Birds receiving the combination of soybean oil with Rosemary essential oil had lowest malondialdehyde concentration in comparison to birds receiving other treatments (p < .05) in the drumstick meat. Also, birds receiving the combination of soybean oil with vitamin E had lowest malondialdehyde concentration in comparison to birds receiving other treatments (p < .05) in the breast meat. The results indicated that treatments did not influence water holding capacity of meat. Also, dietary rapeseed oil and Thyme essential oil supplementations, separately, decreased saturated fatty acid (p < .01) and increased unsaturated fatty acid and unsaturated to saturated fatty acids ratio (p < .01) of drumstick meat tissue in broiler chicken (p < .01). In conclusion, dietary rapeseed oil and Thyme essential oil increased in n‐3 polyunsaturated fatty acids in the drumstick meat (p < .01) and a combination of dietary soybean oil, Rosemary essential oil and vitamin E decreased the lipid oxidation in the meat of broiler chickens (p < .05).

Effects of phytogenic feed additives, probiotic and mannan-oligosaccharides on performance, blood metabolites, meat quality, intestinal morphology, and microbial population of Japanese quail

1. The aim of this experiment was to investigate the effects of ajwain (Trachyspermum ammi) and dill (Anethum graveolens) essential oils (AEO and DEO, respectively), probiotic (PRO) and mannan-oligosaccharides (MOS) on the growth performance, serum metabolites, meat quality, intestinal morphology and microbial populations of Japanese quail.2. A total of 375 one-day-old Japanese quail were randomly allocated into five treatment groups with five replicates of 15 birds each for a 42 d feeding experiment. The dietary treatments were a basal diet (control) or the same diet supplemented with PRO (0.15 g/kg feed), MOS (2 g/kg feed), AEO (0.25 g/kg feed) or DEO (0.25 g/kg feed).3. AEO, MOS, and PRO supplementation increased weight gain, while diets supplemented with AEO decreased feed intake (FI), and improved feed conversion ratio from d 1 to 21 (P < 0.05). The relative weight of the gizzard was higher in birds supplemented with AEO compared to control group, while the birds fed MOS diet had the longest intestine (P < 0.05). Ceca length was greater in control, MOS and PRO groups (P < 0.05). Both essential oils decreased malondialdehyde (MDA) concentration of breast meat and percentage of cooking loss in quail (P < 0.05). The villus length (VL) was greater in birds fed diet supplemented with MOS, AEO, and DEO (P < 0.05).The population of E.coli decreased in Japanese quail fed MOS, while Lactobacilli spp. count was increased in the MOS group (P < 0.05).4. In conclusion, AEO, MOS, and PRO supplementation exhibited a positive effect on growth performance, while lipid peroxidation of the meat decreased in birds fed AEO and DEO diets. The intestinal morphometric indices increased in quail fed the AEO, MOS, and DEO diets. Supplementation with MOS modulated intestinal microbial populations of the Japanese quail.

Influence of Two Plant Extracts on Broiler Performance, Oxidative Stability of Meat and Odorous Gas Emissions from Excreta

A feeding trial was conducted to evaluate the effects of plant extracts derived from Mentha arvensis (MA) and Geranium thunbergii (GT) on broiler performance, carcass yield, digestive organ weights, meat quality and odorous gas emissions from the excreta. A total of 210 one-day-old broiler chicks were randomly assigned to one of the following dietary treatments for five weeks: (1) control, (2) 0.1% MA, (3) 0.05% GT, (4) 0.1% GT and 0.1% mixed preparation with varying ratios such as (5) 0.1% 1MA:1GT, (6) 0.1% 1MA:4GT and (7) 0.1% 4MA:1GT. The weight gain (0–3 weeks) was significantly (P<0.01) increased in response to dietary inclusion of plant extracts; however, no significant differences were observed in breast and thigh meat yield (P>0.05). Additionally, no differences were observed in proventriculus, gizzard, pancreas, small and large intestine weight. When compared with the control group, birds fed plant extracts had the lowest meat TBARS value after 0 and 3 weeks of storage (P<0.05). Moreover, the pH value was significantly lower (P<0.05) in the plant extract supplemented groups at 0 weeks. The faecal H2S emissions were significantly reduced at 0 h and 6 h in all supplemented groups relative to the control (P<0.05). Similarly, NH3 emissions were reduced at 0 h and 6 h for all supplemented groups except the 0.1% 1MA:1GT group (P<0.05). Overall, the results of the present study indicate that plant extracts supplementation can be used to improve performance and meat quality of broiler chickens while reducing the emission of harmful gases from the excreta.

In vitro and in vivo evaluation of thyme (Thymus vulgaris) essential oil as an alternative for antibiotic in quail diet1

The thyme (Thymus vulgaris) essential oil was assessed as antibiotic growth promoter replacement in quail chick diet and in vitro test. In total, 250-d-old Japanese quail chicks (mixed sex) were allocated into 5 dietary treatments of 5 replications (6 females and 4 males in each cage with the size of 40× 90× 25 cm) under a completely randomized design. The dietary treatments were included the control diet, control diet without any additive, control diet plus 100 ppm flavophospholipol as an antibiotic growth promoter, control diet plus 200 ppm TVE, control diet plus 300 ppm TVE, and control diet plus 400 ppm T. vulgaris essential (TVE) oil. Feed intake, BW gain, feed conversion ratio (FCR), organs weight, morphology of intestine, serum lipids, and microbial population were measured on day 35. Lipid oxidation of stored muscle tissue was measured by TBARS test. GC-MS assay, DPPH method, and well diffusion method were evaluated for determination of components, antioxidant, and antimicrobial properties, respectively. FCR improved significantly in 400 ppm TVE compared with 200 and 300 ppm TVE (P < 0.05). The serum triglyceride decreased significantly in both sexes receiving 400 ppm TVE compared with control. Villi height increased significantly in duodenum accompanied by decreasing crypt dept at all TVE levels compared with control and antibiotic. The breast muscle tissue of quail fed on 300 and 400 ppm TVE reduced the rate of oxidation during refrigerated storage compared with control. Thymol was the main component (35.40%) of the thymus oil. The considerable antioxidant activity of TVE was identified by IC50 of 58.48 µg/mL. Moreover, zones of growth inhibition of Gram-positive bacteria and Escherichia coli were numerically greater in different doses of TVE than antibiotics. Therefore, The TVE is suitable alternative component for antibiotic growth promoters by dosing consideration. However, it is possible that antibiotic resistance would increase for these natural compounds along the time.

Examination of the Expression of Immunity Genes and Bacterial Profiles in the Caecum of Growing Chickens Infected with Salmonella Enteritidis and Fed a Phytobiotic

Simple Summary

Salmonellosis is among the most common infectious poultry diseases that also represent a high risk to human health. The pathological process caused by Salmonella enterica serovar Enteritidis (SE) triggers in the caecum the expression of certain genes, e.g., avian β-defensins (gallinacins), cytokines (interleukins), etc. On the other hand, gut microbiota influences the infection potential of pathogens. The present study aimed at revealing the differential expression of genes associated with the immune system and changes in the bacterial communities in the intestine of growing chickens in response to SE infection. We also tested a feed additive, essential oils-based phytobiotic Intebio, as a potential alternative to antibiotics and showed effects of its administration on the caecal microbiome composition and the expression of some genes related to immunity. The phytobiotic showed its efficiency for application in poultry rearing and production.

Abstract

This study was performed to investigate the differential expression of eight immunity genes and the bacterial profiles in the caecum of growing chickens challenged with Salmonella enterica serovar Enteritidis (SE) at 1 and 23 days post inoculation (dpi) in response to SE infection at 19 days of age and administration of the phytobiotic Intebio. Following infection, the genes CASP6 and IRF7 were upregulated by greater than twofold. Chicks fed Intebio showed at 1 dpi upregulation of AvBD10, IL6, IL8L2, CASP6 and IRF7. At 23 dpi, expression of AvBD11, IL6, IL8L2, CASP6 and IRF7 lowered in the experiment subgroups as compared with the control. Examination of the caecal contents at 1 dpi demonstrated a significant decrease in the microbial biodiversity in the infected subgroup fed normal diet. Bacterial content of Lactobacillus and Bacillus declined, while that of Enterobacteriaceae rose. In the infected subgroup fed Intebio, a pronounced change in composition of the microflora was not observed. In the early infection stages, the phytobiotic seemed to promote response to infection. Subsequently, an earlier suppression of the inflammatory reaction took place in chickens fed Intebio. Thus, use of Intebio as a drug with phytobiotic activity in chickens, including those infected with Salmonella, proved to be promising.

Modulation of Growth Performance and Intestinal Microbiota in Chickens Fed Plant Extracts or Virginiamycin

In this study, the effects of plant extracts (PEs) and virginiamycin (VIRG) on broiler growth performance, as well as on host intestinal microbiota composition and function were investigated. A total of 288 one-day-old male Cobb broiler chickens were randomly divided into four treatment groups (with six replicates per group). The duodenal, ileal, and cecal content of six broilers per treatment group after 14 and 28 days of treatment were sampled. This material was used for high-throughput Illumina sequencing of the V3–V4 region of the 16S rRNA gene. The results showed that chickens fed 400 mg/kg plant extracts (HPE group) had significantly higher average body weights at day 28 as compared to the control group (CT; P < 0.05), and lower feed-to-meat ratios over days 15–42 (P < 0.01). Within the HPE group at day 14, the relative abundances of two bacterial phyla and 10 bacterial genera increased significantly in the ileal microbiota, and the relative abundance of three bacterial phyla and four bacterial genera decreased. The relative abundance of the genus Lactobacillus in the cecal microbiota decreased from 21.48% (CT group) to 8.41% (fed 200 mg/kg PEs; LPE group), 4.2% (HPE group), and 6.58% (fed 30 mg/kg virginiamycin; VIRG group) after 28 days. In contrast, Faecalibacterium and unclassified Rikenellaceae increased in abundance in the HPE group (from 18 to 28.46% and from 10.83 to 27.63%, respectively), while Bacteroides (36.7%) and Lachnospiraceae increased in abundance in the VIRG group. PICRUSt function analysis showed that the ileal microbiota of the PE treatment groups were more enriched in genes related to the meolism of cofactors and vitamins. In addition, the cecal microbiotas of the LPE and HPE groups were enriched in genes predicted to encode enzymes within 15 and 20 pathways, respectively. These pathways included protein digestion and absorption, amino acid metabolism, lipid biosynthesis, lipopolysaccharide biosynthesis, the citrate cycle (TCA cycle), and lipoic acid metabolism. Similarly, the VIRG group was enriched in 55 metabolic pathways (17 in the duodenum, 18 in the ileum, and 20 in the cecum) on day 28 (P < 0.05). Thus, the results indicated that the observed increase in broiler growth performance after PE or VIRG supplementation might be attributed to an improvement in intestinal microbial composition and metabolic function.

Effects of oral administration of essential oils on anti-immune stress, antimicrobial properties, and repairing the intestinal damage in broilers challenged by lipopolysaccharide

The aim of the present study was to evaluate the effects of oral administration of essential oils (carvacrol, thyme, and oregano) on anti-immune stress, antimicrobial properties, and repairing the intestinal damage caused by Salmonella enterica lipopolysaccharides (LPS) in broilers. A total of 100 Ross 308 broilers (21-d-old; 1.10 ± 0.11 kg) were randomly allocated to five groups: T1, basal diet + saline; T2, basal diet + LPS; T3, basal diet + 200 μL carvacrol oils + LPS; T4, basal diet + 200 μL thyme oils + LPS; T5, basal diet + 200 μL oregano oils + LPS, with 20 replicates each, and one chicken per replicate per cage. Those challenged by LPS resulted in an immune stress, which manifests as the abnormal growth (P < 0.05) in immune organs, and the content of immunoglobulin G (P < 0.05), tumor necrosis factor-α (P < 0.05), and the rectum temperature (P < 0.05) increased compared with other groups. The oral administration of essential oils controlled the immune stress to a certain extent. The essential oils could reduce harmful bacteria, such as Escherichia coli (P < 0.05) and Salmonella enumeration (P < 0.05), in vivo of broilers. Meanwhile, the essential oils repaired the intestinal damage, which showed a reduction in the villi height (P < 0.05) and goblet cell (P < 0.05) caused by LPS. In conclusion, the essential oils (carvacrol, thyme, and oregano essential oils) controlled the stress reaction and maintained intestinal health to a certain extent.

Effects of star anise (Illicium verum Hook.f.) essential oil on nutrient and energy utilization of laying hens

An experiment using 96 Hy-Line brown laying hens at 29 weeks of age that were randomly allocated to four treatments with eight replicates was conducted to assess the effects of star anise (Illicium verum Hook.f.) oil (SAO) on nutrient and energy utilization. Dietary treatments were corn-soybean meal-based diets supplemented with 0, 200, 400, and 600 mg/kg SAO. The birds were fed the diets for 14 days. The conventional nutrients and amino acids of feed and excreta samples were measured for calculating apparent metabolic efficiency, and gross energy (GE) was analyzed for computation of apparent metabolic energy (AME) and true metabolic energy (TME). Endogenous losses were obtained from another 16 birds for calculating true metabolic efficiency. Birds supplemented with SAO had higher (p < 0.05) metabolic efficiency of crude protein (CP), organic matter (OM), Lys, Met, Arg, and Thr than those of control group. Quadratic effects on utilization of Lys, Met, and Thr were observed (p < 0.05). Inclusion of SAO to diet improved nutrient utilization, and the efficacy is best at 400 mg/kg.