Effect of bee pollen on growth performance, carcass traits, blood parameters, and the levels of metabolic hormones in New Zealand White and Rex rabbits

Impacts of selenium nanoparticles and spirulina alga to alleviate the deleterious effects of heat stress on reproductive efficiency, oxidative capacity and immunity of doe rabbits

Effects of dietary inclusion of spirulina platensis (SP) and selenium nanoparticles (SeNPs) combination (SP-SeNPs) on the reproductive performance in vivo and in vitro, reproductive and metabolic hormones, hemato-bichemical parameters, oxidative stress, and immunity of heat-stressed doe rabbis were evaluated. All supplements significantly increased live litter size at birth and weaning, viability rate at birth, hemoglobin and red blood cells, and plasma T3, T4, insulin, total proteins and albumin compared with control. Plasma estradiol 17-β (pre-mating), progesterone (mid-pregnancy), and prolactin (day -7 postpartum) were significantly increased only by SeNPs (0.3, 0.4, and 0.5 mg/kg). All dietary supplements significantly reduced WBCs, cortisol, lipid profile, and improved liver and kidney functions. Immunoglobulins levels, antioxidants capacity were significantly increased, superoxide dismutase was increased by SeNPs (0.4 and 0.5 mg/kg), while malondialdehyde was reduced by 0.3, 0.4 and 0.5 SeNPs mg/kg. Sexual receptivity, pregnancy rate, viability rate at weaning, ovulation rate, and embryo quality were significantly increased by increasing SeNPs above 0.1 mg, while embryo yield was increased by >0.2 mg SeNPs/kg. A combination of SP and SeNPs, could be potentially used as a strong antioxidant to enhance heat regulation and doe rabbit reproduction via improving reproductive and metabolic hormones, antioxidant status and immunological parameters.

Bee Products for Poultry and Rabbits: Current Challenges and Perspectives

Poultry and rabbit production are important and rapidly growing agricultural subsectors, particularly in several developing countries. To ensure the sustainability of poultry and rabbit production, realistic poultry and rabbit farming practices must be improved. Apitherapy is a traditional alternative medicine that involves the prevention and treatment of some diseases with several bee products including propolis, royal jelly, pollen, and venom. More feeding investigations on the numerous benefits of bee products for poultry and rabbits are crucial to be addressed. Poultry and rabbit production has recently experienced numerous challenges, including climate change, disease spread, and antibiotic misuse. Improving animal welfare, health, and production is a top priority for all livestock farms, as is supplying consumers with safe and healthy products. Therefore, this review aims to collect and investigate recent relevant literature on the use of bee products, as feed additives, drinking water supplements, and injections, for poultry and rabbits to improve animal health and production. From the current findings, bee products can improve the growth and immunological performance of small-livestock animals, such as poultry and rabbits, by activating digestive enzymes, maintaining microbial balance, and promoting vitamin synthesis. Therefore, bee products could be a promising natural alternative to growth promoters, reproductive stimulants, and immunological enhancers in poultry and rabbit farms to provide safe and healthy products for humans.

Effects of Supplementation with Bee Pollen and Propolis on Growth Performance and Serum Metabolites of Rabbits: A Meta-Analysis

The objective of this study was to evaluate the effects of bee pollen (BP) and propolis (PRO) supplementation on rabbits' productive performance and serum metabolites through a meta-analysis. Sixteen peer-reviewed publications were included in the data set. The rabbit strains used in the studies included in the data set were New Zealand White, V-line, Rex, and V-line crosses. Weighted mean differences (WMD) between treatments supplemented with BP or PRO and control treatments were used to assess the magnitude of the effect. BP supplementation decreased (p < 0.001) daily feed intake (DFI) and feed conversion ratio (FCR); however, increased (p < 0.001) average daily gain (ADG) and hot carcass yield (HCY). PRO supplementation reduced DFI (p = 0.041) and FCR (p < 0.001), and increased ADG (p < 0.001) and HCY (p = 0.005). In blood serum, BP supplementation increased total antioxidant capacity (TAC; p = 0.002) and decreased serum creatinine concentration (p = 0.049). Likewise, decreased serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA) were detected in response to BP supplementation (p < 0.05). PRO supplementation increased the TAC in blood serum (p = 0.018); however, decreased serum concentrations of AST, ALT, and MDA were observed (p < 0.05). In conclusion, BP or PRO supplementation can be used as a natural growth promoter in rabbits, and both can also improve rabbits' antioxidant status. However, BP or PRO supplementation does not affect rabbits' renal or hepatic health status.

Effects of Bee Pollen on Growth Performance, Intestinal Microbiota and Histomorphometry in African Catfish

This study aimed to determine the dietary effects of honeybee pollen (BP) on growth parameters, intestinal microbiota, hepatic histoarchitecture, and intestinal histomorphometry of African catfish Clarias gariepinus juveniles. The feeding experiment was carried out in a recirculating aquaculture system under controlled conditions for 21 days to achieve more than a 10-fold increase in weight in fish from the control group. Fish were fed well-balanced commercial feed without any supplements and served as a reference group (group C) and other diets enriched with varying BP levels as 1% (BP1), 2% (BP2), and 3% (BP3). Results showed a significant (p < 0.05) effect of the dietary BP not only on the growth parameters (such as final body weight: 5.0 g to 6.6−7.5 g, weight gain: 0.23 g/d to 0.31−0.35 g/d, body length: 84.7 mm to 93.8−95.9 mm, and specific growth rate: 11.7%/d to 13.1−13.7%/d, group C vs. experimental groups, respectively) but also on the development of beneficially important gut microbiota, such as lactic acid-producing bacteria. In BP-enriched groups, an average of 45% higher body weight gain was observed compared to those reared in the control group. The histological analysis showed that dietary BP may have a positive effect on the development of the intestinal tract and may enhance the absorption of nutrients with the potential ability to maintain a normal hepatic histoarchitecture of the treated African catfish. The results obtained suggest the optimum level of BP additive to feed for African catfish should be 1%.

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.

Impacts of Heat Stress on Rabbit Immune Function, Endocrine, Blood Biochemical Changes, Antioxidant Capacity and Production Performance, and the Potential Mitigation Strategies of Nutritional Intervention

Heat stress has become a widespread concern in the world, which is one of the major environmental stressors and causes substantial economic loss in the rabbit industry. Heat stress leads to multiple damages to the health of rabbits, such as organ damage, oxidative stress, disordered endocrine regulation, suppressed immune function and reproductive disorders, ultimately, induces the decreased production performance and increased mortality. Nutritional approaches, including feeding strategies, adjusting feed formula, and supplementing vitamins, minerals, electrolytes, Chinese herbal medicines, and functional active substances to the feed, were reported to mitigate the detrimental effects of heat stress in rabbits. Therefore, elucidating the damage of heat stress to rabbits; proper management and nutritional approaches should be considered to solve the heat stress issue in rabbits. This review highlights the scientific evidence regarding the effects of heat stress on rabbit's immune function, endocrine, blood biochemical changes, antioxidant capacity and production performance, and the potential mitigation strategies of nutritional intervention to alleviate heat stress in rabbits; which could contribute to develop nutritional strategies in relieving heat stress of rabbits.

Effect of cage density on growth rate, carcass traits, muscle amino acid profile, and antioxidant biomarkers of commercial rabbits

The objective of this work was to elucidate the impact of cage density on growth efficiency, carcass yield, and muscle amino acid profile of fattening rabbits. In total, 96 weaned rabbits were assigned into three cage densities: low cage density (LCD) = 1425 cm²/rabbit; medium cage density (MCD) = 850 cm²/rabbit; high cage density (HCD) = 625 cm²/rabbit. Compared with the HCD, the body gain and feed conversion ratio were better in the LCD and MCD groups (P = 0.003 and 0.004, respectively). The MCD and HCD groups had lower hot carcass weight (P = 0.012) and dressing percentage (P = 0.022) than the LCD group. Compared with the HCD group, the LCD and MCD groups exhibited greater serum GSH (P = 0.029) and SOD (P = 0.032), but significantly lower levels of serum cortisol and cholesterol (P = 0.001 and 0.026, respectively). Regarding the amino acid profile of longissimus dorsi and leg muscles, the LCD group had significantly higher levels of muscle lysine and threonine than the HCD and MCD groups (P˂0.05). The current study indicates that the MCD (850 cm²/rabbit) could maintain an acceptable growth performance, carcass traits, and welfare-related parameters. Furthermore, only the low cage density (1425 cm²/rabbit) may preserve the levels of essential (lysine, isoleucine, and threonine) and nonessential (histidine, proline, and glysein) amino acids in the longissimus dorsi and leg muscles of growing rabbits.

Growth indices, intestinal histomorphology, and blood profile of rabbits fed probiotics- and prebiotics-supplemented diets

In a 12-week feeding trial, 32 rabbits (Chinchilla × New Zealand White; 56 days old; 691 ± 1 g body weight) were used to investigate the effect of pro- and prebiotics as growth enhancer on the growth performance, intestinal mucosal development, hematological and serum biochemical responses of rabbits. The dietary Biotronic® prebiotics and Biovet®-YC probiotics were added at 400 mg/kg and 50 mg/kg, respectively. The rabbits were housed individually and randomly assigned to four dietary treatments (n = 8/group; 50:50 bucks to does) including a control diet (diet 1), diet 2 (control + Biotronic® prebiotics), diet 3 (control + Biovet®-YC probiotics) and diet 4 (control + symbiotics [Biotronic® prebiotics and Biovet®-YC probiotics]). Body weight (BW), average daily gain (ADG), dry matter intake (DMI), and feed conversion ratio (FCR) were monitored. Five rabbits per treatment were used for organ assessment and intestinal histomorphology after feeding trial. Blood samples were collected for hematological and serum biochemical analysis. Results showed that supplementation of Biotronic® prebiotics and symbiotics in rabbit diet significantly (P < 0.05) increased final BW and ADG compared to Biovet®-YC probiotic and control diets. Kidney, lung, esophagus, gastro-intestinal tract, small and large intestines were significantly (P < 0.05) influenced by dietary treatments. Ileal mucosal assessment revealed that villus height (VH), villus width, villus density, crypt depth (CD), and VH:CD ratio of rabbits fed Biotronic® prebiotic and symbiotic diets were similar and significantly (P < 0.05) higher than those rabbits fed control and Biovet®-YC probiotic diets. Packed cell volume of rabbits fed symbiotic and control diets was significantly (P < 0.05) higher than those fed Biotronic® prebiotic and Biovet®-YC probiotic diets. This study suggests that Biotronic® prebiotics and its combination with Biovet®-YC probiotics are good alternative growth promoting feed additives in rabbit nutrition. They improved performance, intestinal development and blood profiles and aid feed digestion, nutrient absorption and utilization in rabbits.

Dose-Dependent Impact of Bee Pollen Supplementation on Macroscopic and Microscopic Structure of Femoral Bone in Rats

Simple Summary

Bee pollen is considered an interesting feed supplement with beneficial health impacts. It contains many basic nutritional compounds that improve growth performance, development and immune response of animals. However, its effect on bone structure has been studied to a limited extent and the results published so far are ambiguous. Therefore, the impact of bee pollen supplementation on selected bone characteristics of rats was investigated in our study. We determined a dose-dependent effect of bee pollen administration on macroscopic and microscopic structure of femoral bone. Several negative effects of bee pollen supplementation at the level of 0.75% on bone features have been demonstrated, while the level of 0.5% did not influence these properties in rats.

Abstract

Bee pollen has been successfully used as a feed additive with beneficial impacts on productive, reproductive, and immune conditions of animals. However, its effect on bone structure and bone health remains controversial. Therefore, the purpose of our study was to examine the impact of bee pollen supplementation on macroscopic and microscopic structure of a femoral bone using rats as suitable animal models. Male rats (1 month-old) were assigned into three groups: control (C group) that was fed a standard diet without bee pollen and two bee pollen supplemented groups (P1 and P2 groups) that received an experimental diet including 0.5% and 0.75% of bee pollen, respectively, for 3 months. A number of unfavorable effects of 0.75% bee pollen administration on bone weight, cortical bone thickness, calcium content, alkaline phosphatase activity, sizes of primary osteons’ vascular canals, Haversian canals and secondary osteons in the cortical bone have been recorded, whereas these bone parameters were significantly decreased in the P2 group versus the C group. On the contrary, the concentration of 0.5% did not affect any of bone features mentioned above. In conclusion, the impact of bee pollen supplementation on femoral bone structure of rats depends on the dose used.

Bee Pollen Supplementation to Aged Horses Influences Several Blood Parameters

In humans and animals, aging leads to a decrease in immune function and an increased susceptibility to infection. Decreased immunity and an increase in the incidence of infectious diseases are particularly notable during the autumn. Bee pollen supplementation improves immunity and antioxidant enzyme activity, as well as general performance. The aim of this study was to evaluate the effects of bee pollen supplementation during the autumn on blood parameters in aged horses. The study was performed on 16 warmblood horses aged 15-26 years. Half of this group received 60 g of bee pollen (soaked in water) daily for 30 days during the autumn season. Blood samples were taken from all horses before and after the supplementation period. Numerous hematological and plasma biochemical parameters including indicators of oxidative stress were determined. The data collected after the supplementation were compared with data collected before the experiment using one-way analysis of variance and paired Student's t-test. In the control group, there was a decline in the total number of red blood cells, hemoglobin, and hematocrit and an increase in some lipid parameters, urea, total plasma proteins, and sulfhydryl groups. Supplementation with bee pollen prevented the variation of these parameters, except for low-density lipoprotein cholesterol. We believe that bee pollen supplementation for aged horses during autumn has beneficial effects because it inhibited some of the adverse changes observed in the control horses during this season.

The Application of Pollen as a Functional Food and Feed Ingredient-The Present and Perspectives

Pollen is recognized as an excellent dietary supplement for human nutrition, which is why it can be found in different forms on the market (granules, capsules, tablets, pellets, and powders). But, the digestibility of pollen’s nutrients is strongly affected by the presence of a pollen shell, which can decrease the bioavailability of nutrients by 50% and more. Since consumers have become more aware of the benefits of a healthy diet and the necessity to improve pollen digestibility, different pollen-based functional food products have been developed and extensive studies were done to estimate the beneficial effects of pollen-based feed on animal growth, health, and rigor mortise stage. Considering the positive effects of pollen nutrients and phytometabolites on human and animal health, the aim of this paper was to give an overview of recent achievements in the application of pollen in the formulation of functional food and animal diets. Special attention was paid to the effects of pollen’s addition on the nutritional, functional, techno-functional, and sensory properties of the new formulated food products. Anti-nutritional properties of pollen were also discussed. This review points out the benefits of pollen addition to food and feed and the possible directions in the further development of functional food and feed for the wellbeing of everyone.