Antioxidant and anti-apoptotic potential of whole-pomegranate extract promoted growth performance, physiological homeostasis, and meat quality of V-line rabbits under hot summer conditions

Dietary Supplementation of Microalgae and/or Nanominerals Mitigate the Negative Effects of Heat Stress in Growing Rabbits

Heat stress (HS) is one of the most significant environmental factors that result in fluctuations and shrinkage in rabbit growth, health, and overall productivity. This study aims to investigate the effects of dietary mineral nanoparticles (selenium or zinc) and/or Spirulina platensis (SP) independently and in combination on stressed growing rabbits. A total of 180 weaned growing New Zealand White rabbits were included in this study and randomly divided into six dietary treatments. Rabbits received a basal diet (control group; CON group) or fortified with SP (1 g/kg diet), selenium nanoparticles (SeNPs, 50 mg/kg diet), zinc nanoparticles (ZnNPs, 100 mg/kg diet), and a mixture of SP and SeNPs (SPSeNPs) or SP and ZnNPs (SPZnNPs) groups for 8 weeks during summer conditions. The obtained results demonstrated a significant increase in the final body weight and weight gain (p < 0.05). Additionally, the feed conversion ratio was improved during the periods from 6 to 14 weeks in the treated rabbits compared to those in the CON group. Dietary supplements considerably improved (p < 0.05) the blood hematology (WBCs, Hb, RBCs, and Hct) and some carcass traits (liver weights and edible giblets). All dietary supplements significantly decreased serum levels of total glycerides (p < 0.0001), AST (p = 0.0113), ALT (p = 0.0013), creatinine (p = 0.0009), and uric acid (p = 0.0035) compared to the CON group. All treated groups (except ZnNPs) had lower values of total bilirubin and indirect bilirubin in a dose-dependent way when compared to the CON group. The values of IgA, IgG, and superoxide dismutase were significantly improved (p < 0.05) in all treated rabbits compared to the CON group. Compared with the CON group, the levels of T3 (p < 0.05) were significantly increased in all treated growing rabbits (except for the ZnNP group), while the serum cortisol, interferon-gamma (IFN-γ), malondialdehyde, and protein carbonyl were significantly decreased in the treated groups (p < 0.05). Dietary supplements sustained the changes in hepatic, renal, and cardiac impairments induced by HS in growing rabbits. Adding SP (1 g/kg diet) or SeNPs (50 mg/kg diet) in the diet, either individually or in combination, improved growth performance, blood picture, and immunity-antioxidant responses in stressed rabbits. Overall, these feed additives (SP, SeNPs, or their mixture) can be applied as an effective nutritional tool to reduce negative impacts of summer stress conditions, thereby maintaining the health status and improving the heat tolerance in growing rabbits.

Prevention of aflatoxin B1 toxicity by pomegranate peel extract and its effects on growth, blood biochemical changes, oxidative stress and histopathological alterations

Contamination of animal feeds with mycotoxins is one of the most serious issues in the world of animal nutrition. The purpose of this study was to assess the efficacy of pomegranate peel extract (PPE) versus oxytetracycline (OXY) in reducing aflatoxin B1 (AFB1) toxicity in rabbits fed contaminated diets. This experiment was done on 48 weaned NZW, four groups (n = 12). The first (AF) served as the control group feed on an infected diet by AFB1 between 0.02 and 0.03 mg/kg BW; second (AF + OXY) received an infected diet by AFB1 and was treated with OXY 200 mg/kg BW/day; third (AF + PPE) received an infected diet by AFB1 and treated with PPE 130 mg/kg BW/day; fourth (AF + OXY + PPE) received an infected diet by AFB1 and treated with a daily oral dose of 100 mg/kg BW/day of OXY + PPE (65 mg/kg BW/day), the experiment lasted for 8 weeks experiment. The treated group with PPE and its combination with OXY concurrent with AF showed amelioration markedly for liver and kidney function. To summarise, adding PPE and combining it with OXY at a half dose to an AFB1-contaminated diet can help minimise the harmful effects of AFB1 on rabbit performance.

Use of zinc nanoparticles and/or prodigiosin to mitigate heat stress in rabbits

Heat stress (HS) is an environmental challenge affecting animals' health, productivity and welfare. This work aimed to inspect the protective effect of zinc oxide nanoparticles (ZnNPs) and/or prodigiosin (PRG) against inflammation, immune dysfunction, oxidative stress and endoplasmic reticulum (ER) stress triggered by HS in growing rabbits. Growing weaned rabbits (one hundred males, 35 days of age) were randomly assigned into four groups. The first group fed a basal diet without supplementation and the 2nd, 3rd, and 4th groups fed diets containing zinc oxide nanoparticles (ZnNPs, 50mg/kg diet), prodigiosin (PRG, 100 mg/kg diet) or their mixture (ZnPRG) under HS conditions for eight successive weeks. The dietary inclusion with ZnNPs and/or PRG significantly boosted FBW (final body weight), CBWG (cumulative body weight gain), and FCR (feed conversion ratio) and had no substantial impacts on the CFI (cumulative feed intake) as compared with those in HS one. All supplemented treatments significantly unveiled an increase in the values of RBCs, hemoglobin, and platelets and significantly decreased in WBCs, basophils and monocytes with non-statistically effects on hematocrit, MCV, MCHC, neutrophils and eosinophils. Compared with the HS group, all supplemental groups showed a significant reduction in TNFα, IL4, IFN-γ, TLR-4 and amyloid A levels and DNA damage markers (Ohdg) and significantly increased in the levels of NO and lysosome activity. Rabbits in the ZnPRG group had significantly higher Ig G and Ig M levels than in other groups. The highest value of CAT and GSH levels were found in rabbits received the mixture of ZnNPs (50mg) and PRG (100mg) in their diets under elevated temperatures. Additionally, both treatments, PRG and ZnNPS, significantly (P<0.001) reduced the values of MDA and MYO, while all treated groups had significantly reduced PC contents compared with the HS group. Co-supplement with ZnPRG showed a considerable restoration in the higher immune expression of reticulum oxidative such GRP78 and IRE1 in hepatic tissues induced by HS conditions. The mixture of ZnNPs and PRG presented more robust effects in mitigating the adverse impacts of HS in rabbits compared with the individual treatments. Collectively, ZnNPs and/or PRG alleviated oxidative stress and DNA damage. In addition, it enhanced the antioxidant capacity and immune function, and downregulated ER stress such as GRP78 and IRE1 signaling in the hepatic tissues of stressed rabbits.

Effect of Feeding Pomegranate (Punica granatum) Peel and Garlic (Allium sativum) on Antioxidant Status and Reproductive Efficiency of Female Rabbits

Egypt’s animal protein shortfall cannot be overcome by expanding the production of large animals alone, but rather by increasing the production of highly reproducing animals in the livestock unit. The goal of this study was to examine how adding pomegranate peel (PP), garlic powder (GP), or a mixture of the two to the diet of does affect their weight, the number of offspring, reproductive performance, hematological indices, and several antioxidants indicators as well as the liver and kidney functions. A total of 20 adult and mature female mixed rabbits at age 4.5–5 months and averaging 3.05 ± 0.63 kg body weight, were allocated into four experimental groups (n = 5). The first group was provided with the basal diet and was considered as control animals, while the second, third, and fourth groups were fed the basal diet supplemented with PP 3.0%, GP 3.0%, and a mixture of PP 1.5% + GP 1.5%, respectively. After 2 weeks of feeding the experimental diets, natural mating with untreated bucks was carried out. The kits were weighed immediately after parturition, and then every week. The study found that rabbits fed with 3% PP led to a 28.5% increase in the number of kits at birth compared to the control group. As an effect of supplementing PP 3%, GP 3%, and PP 1.5% + GP 1.5%, the birth weight increased by 9.2%, 7.2%, and 10.6%, respectively, as compared to the control. Hemoglobin increased significantly in all treatment groups as compared to the control at the age of kit weaning. Lymph cells increased significantly in the rabbits that were fed with GP (3%) than in other groups and even the control. The results showed that creatinine levels were significantly decreased in the PP (3%) and GP (3%) than in control rabbits. The level of triglycerides significantly declines in groups treated with PP (3%) than in other treatment groups and the control. The addition of PP 3% or GP 3% increased the progesterone hormone. The addition of PP 1.5%+GP 1.5% improved the immunoglobulin IgG. The results of superoxide dismutase, catalase, glutathione, and total antioxidant capacity showed a significant decline in groups treated with GP (3%) than other treated groups. In conclusion, pomegranate is a promising substance to include in a rabbit’s diet, followed by garlic to boost reproductive efficiency.

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

In the current study, fennel essential oil was used as an antibiotic alternative compared to gentamycin for enhancing the expression of apoptosis genes and antioxidant enzymes in weaned rabbits as well as meat quality and growth performance. The gene expression of the cell lymphoma 2 (BAX and BCL2), caspase3 (CASP3), and glutathione peroxidase (GPX1) were estimated in the liver tissue using qRT-PCR. A total of 45 Moshtohor weaned male rabbits aged four weeks were randomly allocated to control, T1, and T2 treatment groups; each consisted of 15 weaned male rabbits with five replicates. Rabbits in the T1 and T2 groups were orally supplied with 1 mL fennel oil and 1 mL gentamycin, respectively. Weaned rabbits under different treatments showed increased body weight (BW) at 8 and 12 weeks of age and average daily gain (ADG) at 4-8 and 4-12 weeks of age compared to the control group. Compared to the controls, the weaned rabbits supplemented with fennel oil and gentamycin had lower total cholesterol, triglyceride, and MDA. In addition, villus length, mRNA of BAX, BCL2, Casp3, and GPX were increased in the different treatments compared to the control. Furthermore, the meat of these rabbits was less tender, had a lower aerobic plate count (APC), pH, and was brighter and redder in color than the control. Under the conditions of the present study, the supplementation of weaned Moshtohor rabbits with fennel oil as a natural alternative for gentamycin enhanced feed conversion and daily gain through enhancing villus length and mucus thickness. Additionally, fennel essential oil reduces oxidative stress by increasing the antioxidant enzymes.