Dietary manipulations play an important role in improving the rabbit behaviour and performance and mitigating the negative effects of heat stress (HS) in rabbits. Thus, this study was designed to determine the modulatory role of thyme essential oil (TEO) in improving the blood metabolites, antioxidant status, immunological response, ovarian activity, reproductive traits and fecundity of rabbit does kept under high environmental stress. A total of 100 nulliparous does were used and randomly assigned into five treatments of 20 does each. The basal diet fed to the experimental groups contained TEO at levels of 0, 50, 100, 150 and 200 mg/kg diet for the 1st, 2nd, 3rd, 4th and 5th groups, respectively. The period of TEO treatment was one month during an experimental period of three months during the summer season. Results showed that TEO at a level of 100 mg/kg diet decreased (p ≤ .001) MDA, while increased (≤.001) total proteins (TPs), albumin (AL), globulin (GL), blood haemoglobin, total antioxidant capacity (TAC), haematocrit (Ht) and glutathione (GSH). Conversely, the TEO treatment did not affect GSH peroxidase and superoxide dismutase (SOD). Immunological variables (IgG and IgM), milk production, ovulation rate (OR) and normal embryos percentage were significantly improved by 100 mg TEO/kg diet supplementation. The reproductive variable of stressed rabbit does fed TEO were significantly higher than those in the control diet. Collectively, dietary TEO supplementation can alleviate the negative influences of heat stressed-female rabbits, via enhancing the antioxidant capacity and immunological parameters.

Objective: The potential of extra virgin olive oil (EVOO), betaine (BET), and ginger (GIN), as natural antioxidants, in reducing negative effects of heat stress on physiological responses, antioxidant capacity, semen quality and fertility of bucks under heat stress were investigated.Methods: Forty adult Animal Production Research Institute line rabbit bucks were distributed randomly into four experimental treatments of ten rabbits each. The first treatment was fed the commercial pellet diet (CPD) without supplementation and served as a control. The other three treatments were fed CPD supplemented with EVOO (300 mg), BET (1,000 mg), and GIN (200 mg) per kg diet for 3 consecutive months during the summer season.Results: Supplementation of EVOO, BET, or GIN improved (p<0.05) the sexual desire, progressive motility, vitality, intact acrosome and membrane integrity, sperm cell concentration, sperm outputs and fertility. Seminal plasma total proteins, globulin, total antioxidant capacity, glutathione and glutathione S-transferase, and initial fructose increased (p<0.05), while total lipids, aspartate and alanine aminotransferases and malondialdehyde decreased (p<0.05) compared with the control. In comparing the natural antioxidants treatments, GIN evoked the largest improvement.Conclusion: The inclusion of GIN (200 mg/kg diet) appeared to improve the sexual desire, semen quality and oxidative stress of bucks. This may be a beneficial supplement for the management of rabbit bucks used in natural mating or artificial insemination.

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.

The objective of this study was to evaluate the beneficial effect of Saccharomyces cerevisiae (SC) on growth, intestinal morphometric characteristics, blood indices, redox balance, expression of immune-related genes, and their involvement in disease resistance in sea bream (Sparus aurata). Three hundred healthy sea bream fingerlings were allocated into equal four groups (15 fish per hapa). The first group was served as a control and received a basal diet, while the other three groups were fed diets containing 1, 2, and 4 g/kg diet SC, respectively. At the end of week 16, the daily weight gain, specific growth rate, and feed utilization were significantly higher in the SC2 and SC4 groups than the control (p < 0.05). SC dose-dependently improved intestinal morphology, and the 4 g/kg diet significantly increased dry matter, crude fat, and crude protein percentage of body composition when compared with the control group. The 4 g/kg SC boosted innate immune response and phagocytic activity, and all SC-supplemented diets improved total protein, glucose, triglycerides, and urea concentrations, as well as intestinal digestive enzymatic activities. All estimated oxidative markers were significantly enhanced in the group that received 4 g/kg SC when compared with the control and other SC groups (p < 0.05). Feeding the fish a diet supplemented with 4 g/kg SC markedly regulated the expression of HSP70, IGF1, and IL-1β genes. In addition, the 4 g/kg SC-supplemented diet was the most effective in protecting the fish against Vibrio parahaemolyticus challenge. In conclusion, SC-enriched diet improved growth performance, intestinal morphology, redox homeostasis, and immune response of S. aurata with the 4 g/kg concentration as the most effective.

Recently, nanotechnology approaches have been employed to enhance the solubility, availability, and efficacy of phytochemicals, overcoming some industrial obstacles and natural biological barriers. In this regard, 120 clinically healthy growing V-line rabbits (5 weeks old) reared during the summer season were divided randomly into four equal experimental groups (30 rabbits each). The first group received a basal diet without the supplementation of the nanoemulsion of cardamom essential oil (NCEO) (0 g/kg diet) and served as a control (NCEO 0). The other groups were given diets containing NCEO at levels of 150 (NCEO 150), 300 (NCEO 300), and 600 (NCEO 600) mg/kg diet, respectively. The growth performance (higher LBW and ADG), feed utilization (lower FCR), dressing percentage, and relative weight of the liver were improved significantly in the NCEO-treated groups compared to the control group. Moreover, the dietary treatment significantly decreased the rectum temperature and respiration rate, minimizing the 350 and 325 mg NECO/kg diets. The erythrocyte count, hematocrit, and hemoglobin concentration were significantly increased (p < 0.05), while white blood cells were significantly diminished (p = 0.0200) in the NCEO300 and NCEO600 groups compared to the control group. Treatment with 300 or 600 mg NCEO/kg significantly increased the blood serum total protein and albumin compared to the control group. Meanwhile, the liver enzymes (AST and ALT), uric acid, and creatinine concentrations decreased significantly in the NCEO300 group compared to the control group. The concentrations of triglycerides and total cholesterol were reduced significantly by the dietary treatment. The total antioxidant capacity, dismutase activity, and glutathione concentration were significantly higher, while the malondialdehyde and protein carbonyl levels were significantly lower in the NCEO300 group than in the control. The inflammatory responses and immunity statuses were improved in the blood serum of the NCEO-treated rabbits compared to the control. Heat-stress-induced pathological perturbations in renal/hepatic tissues and NCEO co-treatment successfully re-established and recovered near-control renal–hepatic morphology. In conclusion, a dietary supplementation of NCEO (300 mg/kg) could effectively enhance growing rabbits’ growth indices, feed efficiency, redox balance, immunity, and inflammatory responses during the summer.