Human transferrin receptor can mediate SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been detected in almost all organs of coronavirus disease-19 patients, although some organs do not express angiotensin-converting enzyme-2 (ACE2), a known receptor of SARS-CoV-2, implying the presence of alternative receptors and/or co-receptors. Here, we show that the ubiquitously distributed human transferrin receptor (TfR), which binds to diferric transferrin to traffic between membrane and endosome for the iron delivery cycle, can ACE2-independently mediate SARS-CoV-2 infection. Human, not mouse TfR, interacts with Spike protein with a high affinity (KD ~2.95 nM) to mediate SARS-CoV-2 endocytosis. TfR knock-down (TfR-deficiency is lethal) and overexpression inhibit and promote SARS-CoV-2 infection, respectively. Humanized TfR expression enables SARS-CoV-2 infection in baby hamster kidney cells and C57 mice, which are known to be insusceptible to the virus infection. Soluble TfR, Tf, designed peptides blocking TfR-Spike interaction and anti-TfR antibody show significant anti-COVID-19 effects in cell and monkey models. Collectively, this report indicates that TfR is a receptor/co-receptor of SARS-CoV-2 mediating SARS-CoV-2 entry and infectivity by likely using the TfR trafficking pathway.

Effect of rosemary (Rosmarinus officinalis) leaf meal supplementation on production performance and egg quality of laying hens

This experiment was conducted to investigate the supplemental effect of rosemary leaf meal (RLM) on egg production and egg quality in Lohmann-Brown laying hens. For each treatment, six replicates were performed with four 24-week-old laying hens for a total of 96 chickens. Dried rosemary leaf meal (RLM) was present in the commercial laying hen ration at 0, 1.7, 3.5 and 5.2%, respectively. The interactions between dietary treatments, egg storage temperatures (4 °C, 21.5 °C), and egg storage durations (7, 14, 21, 28, and 35 days) were examined in factorial designs using a fully randomized design. The data were analyzed using the Statistical Analysis System (SAS, 2014, Ver. 9.3) and Tukey's multiple range tests to separate the means. The inclusion of dried RLM at a level of 5.2% (p < 0.05) significantly improved the hens' daily egg production (78.9%). Feed conversion ratio (2.25) and egg weight (56.7 g) compared to control treatment. Similarly, at 3.5% and 5.2% RLM supplementation, eggshell weight (5.876 g) and eggshell strength increased significantly (p < 0.05) (compared to control, a weight of 3.76 kg/cm2 and a shell thickness (0.37 mm) was observed. In addition, the groups fed 5.2% RLM had significantly higher albumin weight (34.9 g/L), albumin height (6.9 mm), and yolk weight (15.6 g/L). l), yolk height (15.9 mm), yolk color (5.3 points), and Hough unit (83.9 points) than the control groups. Regarding the external characteristics of stored eggs, a group of hens fed at rates of 3.5 and 5.2% RLM showed significantly greater (p < 0.05) egg weight with increases in storage temperature and duration as a control group. There was a significant interaction effect between stored eggs collected from the supplemented groups in terms of egg weight, weight loss, shell weight, shell strength, and shell thickness stored at specific temperatures and storage durations. There was a decrease in albumen level and Haugh unit (HU) with an increase in storage temperature and duration over treatment (P < 0.05). Therefore, better external quality was observed in eggs collected from a group of chickens fed 4.5 and 5.2% RLM after 35 days of storage compared to a control group. Mean albumen height, albumen weight, HU, yolk height, and yolk color of eggs stored in the refrigerator (4 °C) were an exception for yolk weight, which was higher compared to room temperature (21.5 °C). Significantly low (P < 0.05) albumen height (6.61 to 2.96 cm), Hough unit (82.49 to 47.64 points), and yolk height (14.66 to 12.35 mm) were observed at 35 days storage recorded in the control group. In conclusion, supplementation with RLM at 3.5% and 5.2% improved the performance and quality of both fresh and stored eggs.

Amelioration of ammonia-induced intestinal oxidative stress by dietary Clostridium butyricum in giant freshwater prawn (Macrobrachium rosenbergii)

The use of Clostridium butyricum in crustacean aquaculture for anti-abiotic stress is yet unknown. Feeds were formulated containing 0, 125, 250, 500, and 1000 mg/kg Clostridium butyricum (2 × 10⁷ CFU/g), respectively. The giant freshwater prawns (Macrobrachium rosenbergii) were fed for 8 weeks in triplicate. The results showed that C. butyricum-supplemented groups improved growth performance significantly with the optimum level at 610 mg/kg. Ammonia stress reduced hemolymph glucose, total protein, total cholesterol, and triglyceride concentrations while dietary C. butyricum significantly increased hemolymph glucose and total protein levels after the ammonia challenge. Ammonia stress increased inducible nitric oxide synthase (iNOS) and nitric oxide (NO) levels, and the treatments supplemented with C. butyricum had considerably enhanced levels of iNOS and NO after stress. Treatment with C. butyricum increased the level of superoxide dismutase (SOD), and decreased the level of malondialdehyde (MDA) and superoxide anion, with the 125 mg/kg treated groups having the extreme value. Furthermore, C. butyricum-treated groups reduced the expression of HSPs after ammonia stress while the ammonia stress induced the expression of HSP60, HSP70, and HSP90. Dietary C. butyricum elevated the expression of peroxiredoxin-5 and toll in response to ammonia stress. The results indicate that dietary supplementation with 125-500 mg/kg of C. butyricum (2 × 10⁷ CFU/g) improved biochemical and antioxidant features as well as intestinal immunity of M. rosenbergii under ammonia challenge by activating the toll signal pathway.

Biomass composition and dry matter yields of feed resource available at Lalo kile district of Kellem Wollega Zone, Western Ethiopia

This study aimed to assess the available livestock feed resources in the Lalo kile district of Kellem Wollega Zone, Western Ethiopia, in terms of species biomass composition and dry matter yield of dominant forage species. The district was stratified into two agro-ecologies: mid-altitude areas and low-altitude areas. The effects of grazing intensity on dry matter yields and biomass composition were analyzed using a randomized complete block design replicated three times having two blocks differed by two agro-ecologies (three mid-altitude kebeles and three low-altitude kebeles). The present study used seventy-two pasture samples and 20 × 20 m forage trees collected randomly from the two agro-ecologies of the study area. The General Linear Model of the SAS 19.0 version was used to compare the effects of the agro-ecology and species on dry matter yield and biomass composition. The result of the study indicated that the average dry matter yield for grasses, legumes, and other herbaceous forages was 1.156 t/ha, 0.242 t/ha, and 0.182 t/ha, with an overall 1.58 t/ha in the study district, respectively. About 73.13% of grasses, 15.32% of legumes, and 11.55% of other herbaceous were the species biomass composition in the study area. The midland agroecology had the average biomass fodder yields 7.98-19.78 kg/tree and 1.06-2.41 kg/shrub while lowland agroecology had 9.87-178.06 kg/tree and 1.34-3.87 kg/shrub. There was an estimate of 74.36-100 kg/ha fodder shrubs and 500-800 kg/ha fodder trees on cultivated and uncultivated land in the study area. The herbage yield of natural pasture is 1.733 t DMha^-1 in the mid and 1.427 t DMha^-1 in the low altitudes of the study area, with a mean herbage yield of 1.58 t DMha^-1 during vegetation cover. The grazing capacity of the study area was 0.23 TLU/ha/year in the mid and 0.19 TLU/ha/year in the low altitudes of the study area, with a mean value of 0.21 TLU ha/year. The presence of limited grazing land in the study area led to overgrazing, which in turn resulted occurrence of land degradation associated with poor biomass yield, low quality and variable supply of feeds between the season. Therefore, this study suggests setting up land-use regulation policy to allocate separate land for feed production and commonly use for livestock feeding to improve livestock productivity and contribute to food security and poverty alleviation of small holder farmers in the study area.

Assessment of livestock feed supply and demand concerning livestock productivity in Lalo Kile district of Kellem Wollega Zone, Western Ethiopia

The purpose of this research was to determine the impact of seasonality on feed balance in the Lalo kile district of the Kellem Wollega Zone of Western Ethiopia. The district was divided into two agro-ecological zones: mid and low altitude. A total of 127 respondents were chosen to be interviewed. To collect the required data in the study areas, a cross-sectional survey was used. To analyses the qualitative data, descriptive statistics were performed, while the General Linear Model (GLM) method was used to assess the impacts of seasonal feed availability and agro-ecology on dry matter yield and production constraints. The result showed that there has been seasonal fluctuation in the feed availability and the feed is generally abundant from June to September. The feed supply in terms of DM, ME, and DCP per household per year was 118.7 kg, 74,781 MJ/kg, and 118.61kg, respectively. The feed balance was negatively associated and substantially different all across the studied areas (P < 0.01). With a year's approach, the annual total feed supply exceeds only 66.13, 25.81, and 87.24 percent of the DM, DCP, and ME demands per household, respectively. As a result, total dry matter production, digestible crude protein, and metabolizable energy supply were only fulfilled for 9, 3.5, and 12 months in the research area's mid-altitude and 7, 3 and 9 months in the study area's low land altitude, respectively. The main limitations in both agro-ecologies of the research area include low production and reproduction, poor use of existing feedstuffs, and poor adoption of improved forage production. As a result, for successful livestock development in the study area, the adoption of better fodder and supplementation of productive animals should be considered.

Maternal and environmental microbes dominate offspring microbial colonization in the giant freshwater prawn Macrobrachium rosenbergii

Microbial colonization is vital for physiological equilibrium in animals. However, the impact of maternal and environmental microbes on microbial succession in the early developmental stages of Macrobrachium rosenbergii remains elusive. In this study, the effects of maternal and environmental microbes on the embryonic and larval microbiota of M. rosenbergii were evaluated by high-throughput sequencing. The results showed that Proteobacteria and Firmicutes were the dominant phyla in the intestine, gonads, and hepatopancreases of maternal prawn. In addition, Actinobacteria was dominant in the intestine while Actinobacteria, Bacteroidetes, and Acidobacteria were dominant in gonads of maternal prawn. During the embryonic stages, Proteobacteria, Actinobacteria, and Bacteroidetes became the dominant phyla. In post-larval stages, Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes tended to dominate. In the water, Proteobacteria, Actinobacteria, and Bacteroidetes were the dominant phyla at 7, 14, and 21 dph water. Maternal microbes prominently impacted the microbial composition during the embryonic stages. Specifically, microbial colonization during embryonic stages was directly related to the maternal hepatopancreas according to source-tracking models. When the post-larvae developed to 7 days, the high contribution to the larval microbiota mimicked the environment. These results indicated that microbial colonization in embryonic and post-larval stages was attributed to the maternal and environmental microbe community, respectively. This study provides a theoretical basis for microbial community manipulation to promote prawn growth and physiological health in aquaculture.