We investigated the effect of adult honey bee pollen nutrition on the flight performance of honey bees. Therefore, caged bees were allowed to perform 30 min of defecation/training flights every second day before flight performance of pollen-fed bees and pollen-deprived bees older than 16 days were compared in a flight mill. We first fed 10 µL of 1 M glucose solution to bees, and after they metabolized this during flight, they were fed 10 µL of 2 M glucose solution for a second flight test. Pollen-deprived bees flew longer and further than pollen-fed bees in both flights. Pollen-fed bees flew faster in the early period at the beginning of flights, whereas pollen-deprived bees were faster in the final phases. Pollen-fed bees were able to raise their maximum flight speed in 2 M glucose solution flights, whereas pollen-constraint bees were not. The two groups did not differ in abdomen fresh weight, but the fresh weight of the head and thorax and dry weight of the head, thorax and abdomen were higher in pollen-fed bees. In a second experiment, we constrained pollen consumption of caged bees during the first 7 days and compared daily consumption of bees from day 8–16 to consumption of bees unrestricted in pollen. We found that pollen-deprived bees perceive the pollen shortage and try to compensate for their needs by consuming significantly more pollen at the later phase of their life than pollen-fed bees of the same age. Still, bees constrained from pollen in the first 7 days did only reach 51.1% of the lifetime consumption of unconstrained bees. This shows that bees can sense the need for essential nutrients from pollen, but their physiological apparatus does not allow them to fully compensate for their early life constraint. Pollen deprivation only in the first 7 days of worker life likewise significantly reduced fresh and dry weights of the body sections (head, thorax, and abdomen) and survival. This underlines the importance of protein consumption in a short critical period early in adult bees’ lives for their development and their performance later in life.

This article presents managed honey bee colony loss rates over winter 2019/20 resulting from using the standardised COLOSS questionnaire in 37 countries. Six countries were from outside Europe, including, for the first time in this series of articles, New Zealand. The 30,491 beekeepers outside New Zealand reported 4.5% of colonies with unsolvable queen problems, 11.1% of colonies dead after winter and 2.6% lost through natural disaster. This gave an overall colony winter loss rate of 18.1%, higher than in the previous year. The winter loss rates varied greatly between countries, from 7.4% to 36.5%. 3216 beekeepers from New Zealand managing 297,345 colonies reported 10.5% losses for their 2019 winter (six months earlier than for other, Northern Hemisphere, countries). We modelled the risk of loss as a dead/empty colony or from unresolvable queen problems, for all countries except New Zealand. Overall, larger beekeeping operations with more than 50 colonies experienced significantly lower losses (p < 0.001). Migration was also highly significant (p < 0.001), with lower loss rates for operations migrating their colonies in the previous season. A higher proportion of new queens reduced the risk of colony winter loss (p < 0.001), suggesting that more queen replacement is better. All three factors, operation size, migration and proportion of young queens, were also included in a multivariable main effects quasi-binomial GLM and all three remained highly significant (p < 0.001). Detailed results for each country and overall are given in a table, and a map shows relative risks of winter loss at the regional level.

To enhance the performance of honey bee colonies and to improve the physiological characteristics of honey bee workers in late winter and early spring (dearth period) in Assiut region, Upper Egypt—three pollen substitutes rich in protein and available in the local market were used and compared with bee bread as a control. The pollen substitutes were administrated at 7-day intervals for 15 wk, from December 2018 to March 2019. The rate of food consumption, sealed brood areas, bee population size, and characteristics of hemolymph of honey bee individuals were measured. Stored bee bread was the best protein source for developing honey bee colonies, continued with date syrup, recording the highest sealed brood areas compared with the rest of the diets. All hemolymph parameters under substitute feeding conditions were less than those determined under control conditions (bee bread), and the numbers of spring bees were more than those of winter bees. Total soluble solids (TSS), total hemolymph count (THC), differential hemolymph count (DHC), and hemolymph protein concentration (HPC) differed significantly among the experimental treatments with a significant superiority of date syrup (diet 3) over the others. It can be concluded that the date syrup was more suitable for honey bee colonies which was more favorable than traditional pollen substitute and improved physiological status of honey bee individuals during pollen scarcity periods. So under Upper Egypt conditions, pollen substitute feeding especially date syrup during the winter-early spring period under pollen scarcity helped honey bee colonies to be developed in the early spring seasons.

Several pesticides may be directly responsible for reducing the performance and losses of honeybee colonies. The action of feeding a nursing honeybee worker sugar solution with a sublethal concentration of seven pesticide groups was evaluated under laboratory conditions. Various physiological characteristics of nursing honeybees including food consumption, development of food glands, body water content, and food reserves were considered as indications for the functional status of nursing honeybee workers. Food consumption rate was significantly reduced in all treatments except two treatments, chlorpyrifos, and thiophanate-methyl. Also, the development of hypopharyngeal glands was significantly reduced in all treatments the reduction ranged between   31 to 55.62%. At the end of the nursing period, the state of metabolism as a food reservoir was determined. A maximum decrease in adult water content was recorded under the effect of lambada-cyhalothrine pesticide treatment without any significant difference in all treatments. Otherwise, the protein content of adults significantly decreased in all treatments except with lambada-cyhalothrine pesticide treatment. Fat content significantly increased in all treatments. The present data reflects the negative effects of sublethal concentration after dietary oral application of certain pesticide groups during the nursing period of the honeybee

Background and Objective: The potato tuber moth (PTM), Phthorimaea operculella (Zeller), is one of the most serious pests affecting potatoes, in fields and stores, in Egypt. In this study, the efficiency of a novel pesticide, sulfoxaflor 24% SC compared with two recommended pesticides, indoxacarb 30% WG and emamectin benzoate 5.7% WG, on Phthorimaea operculella under field conditions. Materials and Methods: The treatments were alone and combined of them at two applications, 15 days’ intervals, at their recommended rates according to the Ministry of Agriculture and Land Reclamation in Egypt against Phthorimaea operculella larvae, during the 2021 and 2022 summer seasons at the farm of the Faculty of Agriculture, Assiut University, Assiut, Egypt. The ANOVA was used to perform the analysis of variance and Henderson and Tilton’s equation was used to calculate the reduction percentage. Results: The foliage infestation in all treatments achieved a robust reduction of Phthorimaea operculella population when the maximal values were reported with emamectin benzoate+sulfoxaflor and the mean of reduction percentage for two applications were 70.5 and 72.5% followed by emamectin benzoate+indoxacarb (64.5 and 67%), sulfoxaflor (51.17 and 64.17%), emamectin benzoate (46.5 and 53.5%) and indoxacarb (44.34 and 44.83%) for experiments at seasons 2021 and 2022, respectively. Conclusion: The use of sulfoxaflor and emamectin benzoate was the preferred pesticide with less harmful effects on the chewing pests of potato plants under field conditions in Egypt.

Progesterone (P4) and vitamin E (Vitamin E) are important in early stage of pregnancy especially in young does. The goal was to investigate effect of injection of P4,Vitamin E and their integration on pregnancy enhancement, embryo dimensions and P4 concentration in young does. 24 animals were divided into 4 equal groups: control group, P4 group (each doe was injected i.m with single dose of 1.0 mg long-acting P4 two days post-mating), Vitamin E group (each doe was injected i.m with 20 IU Vitamin E/kg BW every 3 days from mating to mid-pregnancy and P4+Vitamin E group. All does were ultrasono-graphically examined at days 7,10,12,14,16,18,20 and 22 of pregnancy.Results revealed that P4 and P4+Vitamin E treatment facilitated establishment of pregnancy on day 7 of pregnancy more than the control and Vitamin E alone. Amniotic vesicles diameters on day 12 and fetal length on days 14 and 16 were greater (P<0.05)in P4 and P4+Vitamin E groups. On days 18-22, fetus length was significantly larger in P4 group. P4 concentrations at first week and mid-pregnancy were significantly greater in P4 group followed by P4+Vitamin E.Conclusion: P4 and P4+Vitamin E enhanced the early stage of pregnancy during the first parity of rabbit does.

Vitamin E (Vit. E) is needed for young rabbits to prevent reproductive abnormalities, abortion and poor survivability of kits. Also, exogenous progesterone (P4) is needed for rabbits to enhance early embryonic development because of inadequate corpus luteum (CL) development at this age. Hence, the aim of this study was to investigate the effect of injecting Vit. E and the combination Vit. E+P4 in young does on live body weight (LBW) gain, gestation length (GL), numbers of services/conception (NS), conception rate (CR), abortion rate (AR), litter size (LS), kit weight (KW), total litter weight (TLW), mortality rate (MR) and progesterone (P4) concentration. The group treated with Vit. E+P4 had a greater LBW gain and lesser AR at first and second pregnancy. Treatments did not have significant impact on GL and LS in the first two parities. Treatments resulted in a significantly lesser MR and greater TLW at the second parity. The Vit. E+P4 treatment resulted in a significantly lesser NS at the first parity, while Vit. E alone resulted in a significant reduction in NS at the second parity. Vit. E+P4 had a positive effect on CR at the first parity compared with controls. Vit. E alone increased CR at the second parity compared with that of the control group. The mean P4 concentration from mating to mid-pregnancy at first parity was significantly greater in the Vit. E+P4 than Vit. E and control groups. In conclusion, treatment with Vit. E+P4 at the first parity may be economically applied on rabbit farms because this treatment resulted in a greater maintenance of the first pregnancy and improved reproductive performance at the second parity as compared with results from the Vit. E treated and control groups.