No abstract

Bee pollen is a natural product that has valuable nutritional and medicinal characteristics and has recently garnered increasing attention in the food industry due to its nutritive value. Here, we harvested pollen loads from the Al-Ahsa oasis in eastern Saudi Arabia during spring, summer, autumn, and winter in 2018/2019 to compare the nutritional value of bee pollen protein with the amino acid requirements of honeybees and adult humans. Based on the nutritional value of bee pollen protein, the optimal season for harvesting bee pollen was determined. The composition of the bee pollen showed the highest contents of crude protein, total amino acids, leucine, glutamic acid, valine, isoleucine, threonine, and glycine in samples collected in spring. The highest contents of lysine, phenylalanine, threonine, tryptophan, arginine, tyrosine, and cysteine were observed in samples collected in winter. The highest contents of histidine, methionine, and serine were in samples collected in autumn. Moreover, the highest levels of aspartic acid, proline, and alanine were in samples collected in summer. Leucine, valine, lysine, histidine, threonine, and phenylalanine (except in autumn bee pollen) contents in pollen from all four seasons were above the requirements of honeybees. Leucine, valine, histidine, isoleucine (except in autumn bee pollen), lysine (except in spring and summer bee pollen), and threonine (except in winter and spring bee pollen) in all tested samples were above the requirements of adult humans. In comparison with the minimal amino acid requirements of adult humans and honeybees, the 1st limiting amino acid in bee pollen collected during the different seasons was methionine. Bee pollen collected during spring (March–May) and winter (December–February) can be considered a nutritive food source for adult humans and honeybees.

Seasonal variations in the fatty acid (FA) compositions of pollen loads collected from the Al-Ahsa Oasis in eastern Saudi Arabia throughout one year were determined to identify the optimal season for harvesting bee pollen rich in essential fatty acids (EFAs) and unsaturated fatty acids (UFAs). The highest values (%) of lipids, linolenic acid (C18:3), stearic acid (C18:0), linoleic acid (C18:2), arachidic acid (C20:0), the sum of the C18:0, C18:1, C18:2, and C18:3 concentrations, and EFAs were obtained from bee pollen harvested during autumn. The maximum values (%) of oleic acid (C18:1), palmitic acid (C16:0), UFAs, and the UFA/saturated fatty acid (SFA) ratio were found in bee pollen harvested during summer. The highest concentrations (%) of behenic acid (C22:0), lignoceric acid (C24:0), and SFAs were found in bee pollen harvested during winter. Bee pollen harvested during spring ranked second in its oleic, palmitic, linolenic, stearic, arachidic, behenic, and lignoceric acid concentrations and for EFAs, UFAs, and the UFA/SFA ratio. The lowest SFA concentration was found in bee pollen harvested during summer. Oleic, palmitic, and linolenic acids were the most predominant FAs found in bee pollen. It was concluded that the FA composition of bee pollen varied among the harvest seasons due to the influence of the dominant botanical origins. We recommend harvesting pollen loads during spring and summer to feed honeybee colonies during periods of scarcity and for use as a healthy, nutritious food for humans.

This research evaluates the effect of dietary zinc oxide nanoparticles’ (ZnO NPs) supplementation on growth performance, immunity, oxidative antioxidative properties, and histopathological picture of broiler chicken reared in the summer season. A total of 224 1-day-old male Cobb chicks were randomly allocated to seven groups of dietary treatments (n = 32). Seven isocaloric and isonitrogenous diets were formulated. ZnO NPs were added to the basal diet at seven different levels, 0, 5, 10, 20, 40, 60, and 80 ppm/kg diet, respectively, for 35 days. Results indicated that live body weight (g) did not differ significantly (P > 0.05) between treatment groups, whereas compared to control, the 5 ppm ZnO NPs/kg diet recorded the highest live body weight at 21 and 35 days. No significant effects for the feed consumption (g/bird/period) and feed conversion ratio (g feed/g gain) among treated and control birds were observed. Hematological and immunological variables showed significant (P ≤ 0.05) dose-dependent modulations by ZnO NP supplementation. Significant (P ≤ 0.05) differences were observed in the phagocytic activity, phagocytic index, and IgM and IgG between the treatment groups, with the 5 and 10 ppm ZnO NPs/kg diet recording the best values, followed by the 20 ppm ZnO NPs/kg diet. Different supplementations had nonsignificant effects on the digestibility of nutrients (P ≤ 0.05). Histopathological pictures of the kidney, liver, and lymphoid organs, ultrastructural examination of muscle tissues, and expression of inflammatory cytokines showed dose-dependent morphological and structural changes. In conclusion, the ZnO NP supplementation in broiler diet to eliminate the heat stress hazards in summer season is recommended in dose level of not more than 10 ppm/kg diet.

Phytogenic herbal extracts received considerable attention in the broilers industry as friendly alternative substitutes to antibiotics. These additives can be included in the food or drinking water to enhance birds' growth rate and well-being. Hence, the current investigation examined the effect of including Aloe vera gel in drinking water on the growth rate, biochemical blood indices, and broilers' antioxidative capacity. Cobb 500 broiler chicks (n = 120), 1 day old of initial weight = 48.6 ± 1.65 g, were divided into three treatments where the control group was fed the basal diet without including Aloe vera gel in drinking water. The second and third groups were fed the basal diet, and Aloe vera gel was included in drinking water at 1 and 1.5%, respectively. The final body weight, weight gain, daily weight gain, and feed conversion ratio were significantly improved in birds that received drinking water with Aloe vera gel at 1.5% compared to the control and 1% groups (P ≤ 0.05). The kidney (creatinine and urea) and liver (ALT and AST) function indices of broilers that received drinking water with or without Aloe vera gel showed no significant differences with the control group (P ≥ 0.05). The blood total protein and albumin had higher values in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). The total blood cholesterol, triglycerides, and LDL levels were significantly decreased in the group of birds that received 1.5% Aloe vera gel in drinking water (P ≤ 0.05). The HDL level was higher in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). The total antioxidative capacity (TAC) and glutathione peroxidase (GPX) showed higher activity in the group of birds that received 1.5% Aloe vera gel while the level of malondialdehyde (MDA) was lower in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). In summary, including Aloe vera gel in drinking water enhanced the growth rate, biochemical blood indices, and broilers' antioxidative capacity.