Impact of Fennel Essential Oil as an Antibiotic Alternative in Rabbit Diet on Antioxidant Enzymes Levels, Growth Performance, and Meat Quality

Effect of dietary supplementation of macadamia oil on the growth, immune function, physio-biochemical components and thyroid activity of growing rabbits

The current research aimed to assess the effects of dietary macadamia oil (MO) on carcass traits, growth performance, physio-biochemical components, immune function, thyroid hormones and inflammation markers of growing rabbits. A total of 96 growing rabbits were randomly distributed into four treatments, with 24 rabbits in each group. The rabbits were fed a basal diet (control group) or a diet supplemented with MO at 0.5 (MO0.5), 1 (MO1.0) and 2 (MO2.0) mL/kg of diet for eight weeks. The daily body weight gain and feed conversion ratio showed a quadratic improvement with increasing levels of MO, and the optimal dose was 1.25 mL/kg of diet. Increasing levels of MO also had a quadratic effect on hepatic and renal functions. Dose-response curves revealed that the optimal doses of MO were 1.50, 1.75 and 1.25 mL/kg of diet for total bilirubin, gamma-glutamyl transferase, and creatinine respectively. A quadratic relationship was observed between the increased levels of MO and tumour necrosis factor-α (p = 0.038), interleukin-6 (p = 0.014) and immunoglobulins (p = 0.016 and IgM p = 0.026). Additionally, a linear relationship was observed between the increment in MO levels and both nitric oxide (p = 0.040) and interleukin-4 (p = 0.001). The activities of superoxide dismutase and glutathione peroxidase showed a linear increase with increasing dietary MO content, while xanthine oxidase showed a linear decrease. Total antioxidant capacity showed quadratic improvement (p = 0.035) with the dietary treatment, with the optimal dose observed at 1.25 mL/kg of diet. The inclusion of MO in the diet had a linear effect on the activity of thyroxine (p = 0.001). Therefore, supplementation of MO at a dose of 1 or 1.5 mL/kg of diet in growing rabbits' diets can improve growth and carcass traits, sustain thyroid function by supporting immunity, and reduce oxidative/inflammation pathways.

Effects of essential oils on heat-stressed poultry: A review

While certain animal species are sensitive to heat stress, poultry particularly modern breeds, are more susceptible to high ambient temperatures. This has major implications for the poultry industry, as heat stress causes large financial losses. These economic losses will probably increase as a consequence of a predicted rise in global temperatures. Heat stress adversely affects various aspects of poultry, including physiological responses, growth and production performance, meat quality, egg quality, and reproductive activities. These effects occur through specific molecular and metabolic pathways. To mitigate the impacts of heat stress, it is crucial to go beyond administrative practices and implement dietary interventions during high ambient temperature. Such interventions aim to optimize the development of stressed bird species in terms of performance, health, and profitability. Essential oils have shown promising in mitigating the negative effects of heat stress and improved antioxidant status, growth and yield performance, as well as meat and egg quality in poultry. They actively participate in certain metabolic and molecular pathways that help to counteract the effects of heat stress. The article discusses the impacts of essential oil supplementation on the relationships between antioxidant enzyme activity, these molecular, and metabolic pathways, as well as various parameters such as growth and yield performance, and product quality heat-stressed poultry.

Essential oils as promising treatments for treating Candida albicans infections: research progress, mechanisms, and clinical applications

Candida albicans: (C. albicans) is a prevalent opportunistic pathogen that can cause severe mucosal and systemic fungal infections, leading to high morbidity and mortality rates. Traditional chemical drug treatments for C. albicans infection have limitations, including the potential for the development of drug resistance. Essential oils, which are secondary metabolites extracted from plants, have gained significant attention due to their antibacterial activity and intestinal regulatory effects. It makes them an ideal focus for eco-friendly antifungal research. This review was aimed to comprehensively evaluate the research progress, mechanisms, and clinical application prospects of essential oils in treating C. albicans infections through their antibacterial and intestinal regulatory effects. We delve into how essential oils exert antibacterial effects against C. albicans infections through these effects and provide a comprehensive analysis of related experimental studies and clinical trials. Additionally, we offer insights into the future application prospects of essential oils in antifungal therapy, aiming to provide new ideas and methods for the development of safer and more effective antifungal drugs. Through a systematic literature review and data analysis, we hope to provide insights supporting the application of essential oils in antifungal therapy while also contributing to the research and development of natural medicines. In the face of increasingly severe fungal infections, essential oils might emerge as a potent method in our arsenal, aiding in the effective protection of human and animal health.

Green synthesis, characterization, and hepatoprotective effect of zinc oxide nanoparticles from Moringa oleifera leaves in CCl4-treated albino rats

Hepatotoxin carbon tetrachloride (CCl4) causes liver injury. This research aims to create ZnO-NPs using green synthesis from Moringa oleifera (MO) leaves aqueous extract, and chemically prepared and confirming the synthesis by specialized equipment analysis. The sizes formed of ZnO-NPs were 80 and 55 nm for chemical and green methods, respectively. In addition, to study their ability to protect Wistar Albino male rats against oxidative stress exposed to carbon tetrachloride. MO leaf aqueous extract, green synthesized ZnO-NPs, and ZnO-NPs prepared chemically at 100 and 200 mg/kg BW per day were investigated for their hepatoprotective effects on liver enzyme biomarkers, renal biomarkers, antioxidant enzymes, lipid peroxidation, hematological parameters, and histopathological changes. Compared to the control group, all liver and kidney indicators were considerably elevated after the CCl4 injection. However, the activity of antioxidant enzymes in the liver was significantly reduced after the CCl4 injection. These outcomes indicate that MO leaf aqueous extract, greenly synthesized ZnO-NPs, and ZnO-NPs chemically prepared can restore normal liver and kidney function and activity, as well as hematological and antioxidant enzymes. The highest impact on enhancing the hepatoprotective effect was recorded for rats that received green synthesized ZnO-NPs. The increased drug delivery mechanism of green synthesized ZnO-NPs resulted in a higher protective effect than that of MO leaf aqueous extract.

Feasible feeding strategies for sustainable management of serve heat stress conditions: Effect of Milk Thistle extract on growth performance and health status of newly weaned rabbits

The trail aimed to explore the effect of dietary supplementation of Milk Thistle (MT) extract on growth performance and health status of growing rabbits exposed to serve heat stress condition, considering the economic efficiency of supplementation. A total of 96 weaned male rabbits were divided into 4 groups (24 rabbits/group). The first group received the basal diet without any supplementation and served as a control (MT0), while 2nd, 3rd and 4th groups supplemented with MT at levels of 5 (MT5), 10 (MT10) and 15 (MT15) g/kg diet, respectively, for 10 consecutive weeks. Both of growth performance and feed utilisation were significantly enhanced by the dietary treatment, the optimum dose of MT was 12 g/kg diet for average daily gain, specific growth rate and performance index. However, it was 13 g/kg diet for feed conversation ratio. The polynomial regression analysis showed that the lowest values of rectal temperature and respiration rate were observed at doses of 11 and 13 g/kg diet respectively. The dressing percentage and the relative weights of liver and total edible giblets were significantly improved by the treatment (p = 0.0416, 0.0112 and 0.0032, respectively), maximising in the MT10 group. The MT10 and MT15 groups showed higher erythrocytes and leucocytes counts and lower levels of urea, creatinine and total cholesterol compared to the control (p < 0.05). Liver functions significantly enhanced in aforementioned two treated groups, the liver ultrastructure represented normal cytoplasmic organelles, and nucleus and mitochondria in MT10 group, while the MT15 group showed hepatocytes with dilated nucleus with most cytoplasmic organelles appeared well organised and normal except few small cytoplasms vacuolated. The levels glutathione, superoxide dismutase, catalase and total antioxidant capacity as well as immunoglobulin M, and immunoglobulin G significant improved in the MT-Treated groups compared to the control (p < 0.05). Economically, MT supplemented diets improved the net revenue of fattened rabbits during the summer season. In conclusion, the supplementation of MT extract at levels of 10 or 15 g/kg diet enhanced growth performance, feed utilisation, dressing percentage, hemato-biochemical attributes, immunity and redox balance of heat stressed growing rabbits during the hot season.

Does dietary supplementation with lettuce seed oil enhance broiler performance, immunity, lipid profile, liver and kidney functions, antioxidant parameters, and intestinal microbiota?

The aim of this research was to evaluate the influence of lettuce seed oil (LSO) on the performance, carcass yield, kidney and liver indices, immunity, lipid profile, and cecal microbiota of fattening chicks. A total of 200, 7-day-old Cobb-500 were distributed into 5 experimental groups; each group contained 5 replicates with 8 birds each. The first group 1) the basal diet (only); 2) the basal diet plus lettuce seed oil (0.50 mL/kg); 3) the basal diet plus lettuce seed oil (1.00 mL/kg); 4) the basal diet plus lettuce seed oil (1.50 mL/kg); and 5) the basal diet plus lettuce seed oil (2.00 mL/kg). No significant effect was observed on growth performance, carcass traits, or kidney function at any level of oil. But, liver function was significantly affected due to LSO levels. Serum lipid profiles (total cholesterol-TC, triglyceride-TG, low-density lipoprotein-LDL, and very low-density lipoprotein-VLDL) were significantly reduced by using LSO levels compared to the control group. Dietary LSO significantly increased immunological and antioxidant parameters, except for malondialdehyde-MDA, which was reduced. On the other hand, the cecal microbiota was significantly improved by LSO additives. It was concluded that the dietary supplementation of LSO had beneficial effects on liver and kidney functions, lipid profile, immunity, antioxidant parameters, and the bacteriology of fattening chicks.

Effects of dietary supplementation of cumin (Cuminum cyminum L.) essential oil on expression of genes related to antioxidant, apoptosis, detoxification, and heat shock mechanism in heat-stressed broiler chickens

This study was carried out to evaluate the impact of cumin essential oil (CEO) supplementation on levels of certain gene expression related to antioxidant, apoptotic, detoxific, and heat shock mechanisms in the breast meat and ileum of heat-stressed broilers. The study was conducted on a 2 × 6 factorial design (heat stress + feed additive) on 600 day-old male broiler chicks for a period of 42 days. From day 7 to 42, although broilers in heat stress groups (HT) were exposed to constant chronic heat stress (36 °C), others were housed at thermoneutral ambient temperature (TN). The chicks in both conditions were fed with 6 experimental diets: C0 (basal diet with no additive), ANTIB (basal diet + 100 mg/kg chloramphenicol), VITE (basal diet + 50 IU α-tocopherol), C2 (basal diet + 200 mg/kg CEO), C4 (basal diet + 400 mg/kg CEO), C6 (basal diet+ 600 mg/kg CEO). The results showed that heat stress upregulated (except for Bcl-2) the genes related to antioxidant, apoptosis, detoxification, and heat shock mechanism. However, cumin essential oil increased the dose-dependently positive effect on certain genes in tissues of the heat-stressed broilers and downregulated (except for Bcl-2) these genes.

Dietary Supplementation with Pithecellobium dulce (Roxb) Benth Fruits to Fattening Rabbits

Pithecellobium dulce produces a fruit used in alternative medicine that could be utilized to feed rabbits. The objective of this study was to measure the effect of the P. dulce fruit on productive performance, carcass traits, meat characteristics, and meat product quality as well as shelf-life. Seventy-two California × English pot crossbreed rabbits (35 d age) were randomly distributed into two treatments: a control group without P. dulce and another group fed with 5% of P. dulce, and fattening for 28 d. Productive performance parameters, blood biochemistry and hematology, apparent digestibility, carcass traits, meat characteristics, and meat product shelf-life were measured. The results indicate inclusion of 5% P. dulce improves (p < 0.05) dry and organic matter digestibility and feed conversion rate, but some serum blood enzymes were increased (p < 0.05). The a* value, hardness, and pH decreased (p < 0.05) in the group fed with P. dulce. Antioxidant properties in the meatballs were different (p < 0.05), improving shelf-life and acceptance in sensory analysis. In conclusion, the use of 0.5% of P. dulce fruits to feed fattening rabbits can be used to improve the shelf-life of rabbit meat.

Controlling bacterial biofilm formation by native and methylated lupine 11S globulins

The antibacterial and anti-biofilm activities of the 11S globulins isolated from lupin seeds (Lupinus termis), and its methylated derivative (M11S), were investigated against seven pathogenic gram-positive and gram-negative bacteria. The MIC of 11S ranged from 0.1 to 4.0 μg/ml against 0.025 to 0.50 μg/ml for M11S, excelling some specific antibiotics. The MICs of M11S were 40-80 times lower than some specific antibiotics against gram-positive bacteria and 2-60 times lower than some specific antibiotics against gram-negative bacteria. One MIC of 11S and M11S highly reduced the liquid growth of all tested bacteria during 24 h at 37°C. They also inhibited biofilm formation by 80%-86% and 85%-94%, respectively (gram-positive), and 29%-44% and 43%-50%, respectively (gram-negative). M11S prevented biofilm formation by gram-positive bacteria at minimum biofilm inhibitory concentration (MBIC), 0.025-0.1 μg/ml against 0.1-0.5 μg/ml for gram-negative bacteria, i.e., 4-20 times and 4-7 times anti-biofilm inhibitory action compared with 11S, respectively. Biofilm formation of two bacteria revealed no adhered cells on glass slides for 24 h at 37°C, i.e., was entirely prevented by one MBIC of 11S and M11S. Scanning electron microscopy indicated microbial biofilm deformation under the action of 11S and M11S, indicating their broad specificity and cell membrane-targeted action.

Sesamin alleviated fluoride - induced thyroid endocrine disruption in zebrafish (Danio rerio)

Previous studies have indicated that fluoride could induce the damage of thyroid. However, the effects of sesamin on thyroid endocrine function in zebrafish exposed to fluoride have not been clarified. This study was designed to investigate the alleviating effects of sesamin on thyroid endocrine disruption in zebrafish induced by fluoride. The results showed that sesamin significantly improved growth performance in adults exposed to fluoride; decreased significantly the mortality rate, increased remarkably the hatching rate and body length, and alleviated the phenomenon of spinal curvature, yolk cyst and pericardial cyst to varying degrees in fluoride-exposed embryos and larvae. Sesamin alleviated remarkably the damage of thyroid tissues in fluoride-exposed adults. Moreover, sesamin obviously reduced oxidative stress and improved the imbalance of thyroid hormones in fluoride-exposed adults or larvae. In addition, sesamin reversed the expression of endocrine-related genes of thyroid in fluoride-exposed adults or larvae. This indicates that sesamin can affects the thyroid tissue structure, hormone levels, and the expression of endocrine-related genes of thyroid, thus alleviating the thyroid endocrine disorder induced by fluoride and improving the growth and development. This study also demonstrates that sesamin can be a promising novel treatment for thyroid endocrine disorder caused by fluoride.

Struggling Thermal Stress Impacts on Growth Performance and Health Status of Newly Weaned Rabbits Using Nanoemulsion of Origanum majorana Considering the Economic Efficiency of Supplementation

With the recent trend of global warming, HS-instigated diminishing could extremely jeopardize animal health, productivity, and farm profit. Marjoram essential oil (MEOE) is a worthy source of wide range phytogenic compounds that may improve heat tolerance, redox and inflammatory homeostasis, and immunity of newly weaned rabbits, specifically if included in the diets in a nano form. One hundred newly weaned rabbits were randomly distributed into four homogeneous groups. The first group (control group) included rabbits that received basal diet without supplementation. In contrast, the other three groups included rabbits that received basal diets supplemented with 200 (MEONE200), 400 (MEONE400), and 800 (MEONE800) mg MEONE/kg diet, respectively. Among MEONE-treated groups and control groups, MEONE400 group showed the highest (p < 0.001) growth performance traits, including final body weight, average daily gain, feed efficiency, and the performance index. Compared to the control, all MEONE-supplemented groups possessed lower rectal temperatures and respiration rates, recording the lowest values in the MEONE400 group. The oxidative stress biomarkers and immunoglobulins G and M were significantly improved in the MEONE400 and MEONE800 compared with the control and MEONE200 groups. The addition of MEONE (400 or 800 mg/kg) decreased the concentrations of serum interleukin-4 (p = 0.0003), interferon gamma (p = 0.0004), and tumor necrosis factor-α (p < 0.0001) but significantly elevated (p < 0.001) the activity of nitric oxide, amyloid A and lysozyme. Liver functions (lower concentrations of liver enzymes) were significantly improved in all MEONE-treated groups compared to the control group. There was a considerable significant effect of dietary supplementation of MEONE400 on economic efficiency. In conclusion, the addition of 400 mg/kg to the diets of newly weaned rabbits can be recommended as an affective intervention to mitigate the negative impacts of HS.

Exposure to a sensory functional ingredient in the pig model modulates the blood-oxygen-level dependent brain responses to food odor and acute stress during pharmacological MRI in the frontostriatal and limbic circuits

Introduction

In the present study, we examined the effects of a supplementation with a sensory functional ingredient (FI, D16729, Phodé, France) containing vanillin, furaneol, diacetyl and a mixture of aromatic fatty acids on the behavioural and brain responses of juvenile pigs to acute stress.

Methods

Twenty-four pigs were fed from weaning with a standard granulated feed supplemented with the functional ingredient D16729 (FS animals, N = 12) or a control formulation (CT animals, N = 12). After a feed transition (10 days after weaning), the effects of FI were investigated on eating behaviour during two-choice feed preference tests. Emotional reactivity to acute stress was then investigated during openfield (OF), novel suddenly moving object (NSO), and contention tests. Brain responses to the FI and the two different feeds' odour, as well as to an acute pharmacological stressor (injection of Synacthen®) were finally investigated with functional magnetic resonance imaging (fMRI).

Results

FS animals tended to spend more time above the functional feed (p = 0.06) and spent significantly more time at the periphery of the arena during NSO (p < 0.05). Their latency to contact the novel object was longer and they spent less time exploring the object compared to CT animals (p < 0.05 for both). Frontostriatal and limbic responses to the FI were influenced by previous exposure to FI, with higher activation in FS animals exposed to the FI feed odor compared to CT animals exposed to a similarly familiar feed odor without FI. The pharmacological acute stress provoked significant brain activations in the prefrontal and thalamic areas, which were alleviated in FS animals that also showed more activity in the nucleus accumbens. Finally, the acute exposure to FI in naive animals modulated their brain responses to acute pharmacological stress.

Discussion

Overall, these results showed how previous habituation to the FI can modulate the brain areas involved in food pleasure and motivation while alleviating the brain responses to acute stress.

Supplying Bee Pollen and Propolis to Growing Rabbits: Effects on Growth Performance, Blood Metabolites, and Meat Quality

The objective of this study was to evaluate the effect of supplementation with bee pollen (BP) and propolis (PRO) on productive performance, Eimeria oocyst counts in feces, blood metabolites, and the meat quality of growing rabbits. A total of 160 hybrid rabbits (California × New Zealand) of 30 days of age and 643 ± 8.0 g body weight (BW) were assigned to four treatments with 10 replicates each (four rabbits/replicate). The treatments were as follows: (1) CON: rabbits fed basal diet and not supplemented with BP or PRO; (2) BP500: CON + BP (500 mg/kg BW); (3) PRO50: CON + PRO (50 µL/kg BW); and (4) BP + PRO: CON + BP (500 mg/kg BW) + PRO (50 µL/kg BW). Higher daily weight gain (p = 0.04) and lower feed conversion rate (p = 0.03) were observed in rabbits supplemented with PRO50. In addition, supplementation with PRO50 and BP + PRO reduced the amount of Eimeria oocysts per gram of feces (p < 0.05). Most hematological and serum biochemical parameters were similar in rabbits of all treatments. Protein content, collagen, and meat color were similar between treatments. In conclusion, propolis supplementation (50 µL/kg BW) can prevent coccidiosis and act as a natural growth promoter in rabbits without affecting animal health and meat quality.

Use of zinc oxide nanoparticles in the growing rabbit diets to mitigate hot environmental conditions for sustainable production and improved meat quality

Background

This study evaluated the modulatory effects of zinc oxide nanoparticles (ZnO-NPs) supplementations on the productive performance, blood biochemistry, carcass criteria, and meat quality of White New Zealand rabbits reared under hot conditions. A total of 125 White New Zealand male rabbits (body weight, “650 ± 11”, 30 days old) were assigned to five treatment diets: basal diets supplemented with ZnO-NPs at 0, 20, 40, 60, or 80 mg/kg for 60 days. Each treatment was replicated 25 times with one rabbit each.

Results

The body weight (BW), BW gain, and feed intake linearly increased with zinc oxide nanoparticle supplements. Supplementation of ZnO-NPs at 20, 40, 60, and 80 mg/kg significantly improved (linear, P < 0.05) the feed conversion ratio compared to the control group. Moreover, supplementation of ZnO-NPs at these inclusions 20, 40, 60, and 80 mg/kg significantly (P < 0.05) decreased the serum cholesterol, alanine aminotransferase, and aspartate aminotransferase, creatinine, and urea compared to control group. The lipid oxidation was lower, and the water holding capacity of rabbit meat was improved (P < 0.001) in rabbits fed on 20, 40, 60, and 80 mg/kg ZnO-NPs supplemented diets compared to control.

Conclusion

The results suggested that dietary supplementation of ZnO-NPs (20–80 mg/kg) can mitigate the negative impacts of heat stress on rabbit performance and health. Its supplementation improved growth performance and meat physicochemical properties, and blood biochemistry parameters of White New Zealand rabbits.

Impact of Dietary Lavender Essential Oil on the Growth and Fatty Acid Profile of Breast Muscles, Antioxidant Activity, and Inflammatory Responses in Broiler Chickens

This study aimed to investigate the impact of dietary addition of lavender essential oil (Lavandula angustifolia L.) (LEO) on the growth performance, tissue histoarchitecture, and fatty acid profile in breast muscles, as well as blood biochemistry and immune expression of pro-inflammatory cytokines of broiler chickens. A total of 200 three-day-old broiler chickens (average body weight 101.3 ± 0.24 g) were assigned to a completely randomized design consisting of four dietary treatments (n = 50 per treatment, each replicate consisting of 10 birds) that included lavender essential oil at concentrations of 0 (control group), 200, 400, and 600 mg Kg−1 diet. The experiment lasted for 35 days. The results revealed that supplementation of lavender essential oil at 200, 400, or 600 mg/kg in broiler diets had no effect (p > 0.05) on the growth performance throughout the experimental periods (3−10, 11−23, and 24−35 days of age). According to the broken line regression model, the optimal level for dietary LEO addition was the 460 mg kg−1 diet based on the total body weight gain and feed conversion ratio results. The diets supplemented with lavender essential oil had no effect (p > 0.05) on the percentages of carcass yield or internal organs. Dietary addition of LEO significantly increased the percentages of omega-3 polyunsaturated fatty acids PUFA (n-3), omega-6 polyunsaturated fatty acids (n-6), and the n-3/n-6 ratio (p < 0.05) in the breast muscles of chickens in a level-dependent manner. The blood concentration of alanine aminotransferase was significantly increased in lavender essential oil at 600 mg kg−1 compared with other treatments. The dietary addition of LEO at 200, 400, and 600 mg kg−1 significantly reduced the malondialdehyde level. Still, they significantly increased the serum enzyme activities of total antioxidant capacity, catalase, superoxide dismutase, and the pro-inflammatory cytokine (interleukine-1 beta and interferon γ) compared with the unsupplemented group. The LEO-supplemented groups showed normal liver histomorphology as in the control group. However, the immunoexpression of the pro-inflammatory cytokine transforming growth factor β was significantly increased by increasing the level of LEO. It can be concluded that lavender essential oil can be included in broiler chicken diets up to 460 mg kg −1 with no positive effect on the bird’s growth. It can improve the antioxidant capacity and enrich the breast muscles with PUFA. An increased level of supplementation (600 mg kg−1) increased the inflammatory responses in broiler chickens.

Medium chain triglycerides improve the growth performance, immune and antioxidant functions, and intestinal health of weaned rabbits

The purpose is to study the effects of different doses of medium chain triglyceride (MCT) on growth performance, immune and oxidative functions, and intestinal health of weaned rabbits. A total of 600 weaned rabbits weighing about 993.26 g and at 35 d of age were randomly divided into five groups. The control group was fed a basal diet containing 2400 mg/kg soybean oil, and the experimental group was substituted with 600, 1200, 1800, and 2400 mg/kg MCT. The whole trial period lasted for 48 d. The results showed that treatment with 2400 mg/kg MCT significantly increased the weaning survival rate and crude fat digestibility (p < 0.05) and dramatically raised the levels of serum immunoglobulin (Ig)A, IgG, IgM, catalase, superoxide dismutase, and total antioxidant capability (p < 0.05). The villus height and crypt depth in 1800 mg/kg MCT group were observably enhanced (p < 0.05). The abundance of Bacteroidetes was significantly increased in 1800 and 2400 mg/kg MCT groups (p < 0.05). In conclusion, 1800 and 2400 mg/kg MCT substituting soybean oil in the diet of weaned rabbits can improve the growth performance and intestinal barrier function of weaned rabbits.