Maternal supply of methionine during late-pregnancy enhances rate of Holstein calf development in utero and postnatal growth to a greater extent than colostrum source

Background: Pregnancy and early life are critical periods of plasticity during which the fetus and neonate may be influenced by environmental factors such as nutrition.Maternal methionine(Met) supply in non-ruminants during pregnancy can affect offspring development and growth.Thus,the objective of this study was to investigate if increasing Met supply during late-pregnancy affects developmental parameters of the calf at birth and if either maternal Met or colostrum from Met-fed cows alters calf growth.Calves born to Holstein cows individually-fed a basal control [CON; 1.47 Mcal/kg dry matter(DM) and 15.3% crude protein] diet with no added Met or CON plus ethylcellulose rumen-protected Met(MET; Mepron? at 0.09% of diet DM; Evonik Nutrition Care GmbH,Germany)during the last 28 ± 2 d of pregnancy were used.A total of 39 calves were in CON(n = 22 bulls,17 heifers) and 42 in MET(n = 20 bulls,22 heifers).At birth,calves were randomly allocated considering dam treatment and colostrum as fol ows: 1) calves from CON cows and colostrum from CON cows(n = 21); 2) calves from CON cows and colostrum from MET cows(n = 18); 3) calves from MET cows and colostrum from MET cows(n = 22); and 4) calves from MET cows and colostrum from CON cows(n = 20).Al calves were housed,managed,and fed individual y during the first 9 wk of life.Results: Despite greater daily DM intake pre-partum in cows fed MET(15.7 vs.14.4 ± 0.12 kg/d,P 0.05),colostrum quality and quantity were not affected by maternal diet.At birth,MET calves had greater(P ≤ 0.05) body weight(BW,44.1 vs.42.1 ± 0.70 kg),hip height(HH,81.3 vs.79.6 ± 0.53 cm) and wither height(WH,77.8 vs.75.9 ± 0.47 cm).In contrast,concentrations of His,Lys,and Asn in plasma were lower(P ≤ 0.05) in MET calves.Regardless of colostrum source,the greater BW,HH,and WH in MET calves at birth persisted through 9 wk of age resulting in average responses of + 3.1 kg BW,+ 1.9 cm HH,and + 1.8 cm WH compared with CON.Average daily gain during the 9 wk was(P 0.05) 0.72 ± 0.02 kg/d in MET compared with 0.67 ± 0.02 kg/d in CON calves.Respiratory scores were normal and did not differ(P 0.05) due to maternal Met supply or colostrum source.However,fecal scores tended to be lower(P ≤ 0.10) in MET calves regardless of colostrum source.Conclusions: Increasing the maternal supply of MET during late-pregnancy enhanced growth in utero as wel as during the pre-weaning and early post-weaning periods.Although the ～ 1 kg/d greater DM intake during the last 2–3 wk prior to parturition could explain a portion of the 2 kg extra body mass of MET calves at birth,other mechanisms potential y encompassing nutrient assimilation efficiency likely played a role.Assessing the exact mechanisms sensitive to supply of Met or total amino acid supply during the latter stages of growth in utero merit further research.     

Screening for Antifungal Potential of Plant Extracts of Fifteen Plant Species Against Four Pathogenic Fungi Species

The antifungal activity of fifteen wild plant species grown in the Al-Qassim region, Saudi Arabia, was investigated against the fungi species Fusarium solani, Botrytis cinerea, Alternaria alternata and Stemphylium botryosum at concentrations of 10, 20, 40 and 80?g/L. The inhibitory effect of test extracts varied among examined fungi, and Fusarium solani exhibited the least sensitivity compared to other fungi species. Antifungal activity of the tested extracts was proportional to the applied dose. Extracts of Lactuca virosa, Neurada procumbens, Ochradenus baccatus and Cyperus conglomerates showed relatively low inhibition effects on the fungi species. The most effective plants were Pulicaria undulata, Artemisia monosperma, Prosopis juliflora, Withania somnifera and Rumex vesicarius. At 80?g/L, extracts of these plant species reduced mycelial growth of Botrytis cinerea by 16.5–32.2%, of Fusarium solani by 11.1–27.9%, of Alternaria alternaae by 26.9–63.5% and of Stemphylium botryosum by 22–40%. The methanolic extract of the most effective plant species was further fractioned with hexane, methylene chloride and ethyl acetate. The obtained fractions varied in their effects on mycelial growth of the four tested fungi. Using the same fraction resulted in different inhibition effects on mycelial growth of all tested fungi. The antifungal activity of each crude extract tended to be distributed among its three fractions, probably because the bioactive components were also distributed among the fractions.     

Using CERES-Maize model to determine the nitrogen fertilization requirements of early maturing maize in the Sudan Savanna of Nigeria

CERES-Maize model was used to determine nitrogen fertilizer requirements of early maturing maize varieties in the Sudan Savanna. Data were collected from 2013 to 2014 field experiments conducted in Bayero University Kano, (BUK), Kano, Nigeria. The experiments consisted of three nitrogen fertilizer levels (0, 60, and 120 kg N ha^?1) and two early maize varieties (EVDT and 2009 TZEEW). Sensitivity analysis was performed to evaluate the responses of the two maizes to N fertilizers and for economic and strategic responses. The model predicted grain yield and harvest index reasonably well for the two varieties. Increasing N application from 0 to 30 kg N ha^?1 increased grain yield by 105%, when nitrogen (N) rate was increased to 60 kg N ha^?1, grain yield increased by 226%. Yield increases of 364%, 451%, and 461% was observed when N rate increased from 0 to 90, 120, and 150 kg ha^?1, respectively.     

Effects of Hydrophilic Polymer on the Survival of Buttonwood Seedlings Grown Under Drought Stress

The effect of 0.0 (control), 0.1, 0.2, 0.4, and 0.6% of the hydrophilic polymer “Stockosorb K-400” hydrogel (HG) on survival and growth of buttonwood (Conocarpus erectus L.) seedlings grown in sandy soil under drought stress was investigated. The ability of the soil to retain water increased with increasing hydrogel concentrations. The highest level of the HG was capable of changing the typical sandy soil to a loam or even silty clay in terms of water potential and water content. The highest HG concentration prolonged the time of water loss from the soil by about 66% more than the control soil. During drought stress, the seedlings grown in 0.6% HG-mixed soil survived three times as long as those grown in the control soil. Shoot and root growth increased significantly in HG-amended soil as compared with non-amended soil. Plant water potential increased significantly with HG application, thus it aided in the establishment and growth of C. erectus seedlings under water stress conditions. There were no significant differences between 0.4% and 0.6%. The study indicated that an amendment of soil with 0.4% to 0.6% of the hydrophilic polymer “Stockosorb K-400” can be used in arid and semi-arid areas to enhance the drought tolerance of C. erectus seedlings.     

Molecular Screening and Biocontrol of Aflatoxigenic Fungi in Fish Feed

ABSTRACT

Contamination of fish feed (FF) with aflatoxigenic fungi is an ongoing hazardous risk and is the first route for transferring aflatoxins to consumers from fish products. Prevention is the gold standard to deal with microbial food contamination. Different FF samples (n = 38) were screened for the occurrence of fungal contamination, and identified Aspergillus flavus isolates were assessed for the presence of aflatoxigenic production genes (Nor-1, Ver-1, and Omt-A) and the ability to produce aflatoxins. Biocontrol of aflatoxigenic A. flavus was proposed via exposure to plant (Cinnamon bark, Athl, and Lilac leaves) smoldering fumes (PSF). Numerous fungal species were identified from FF; Aspergillus spp. was the prevalent genus, followed by Penicillium spp. and Fusarium spp. The complete set of aflatoxigenic genes was detected in 54.8% of A. flavus isolates and was correlated with their aflatoxin-producing ability. The PSF exposure was successful for inhibiting A. flavus growth in agar media and in contaminated fish feed. Cinnamon PSF was the most effective and could entirely inhibit fungal growth at a proportion of 20 g/m³ in both treatments. The PSF exposures could be suggested as effectual techniques for complete biocontrol of aflatoxigenic fungi in fish feed to protect fish and consumers from their threatening effects.     

Dieckol and Its Derivatives as Potential Inhibitors of SARS-CoV-2 Spike Protein (UK Strain: VUI 202012/01): A Computational Study

The high risk of morbidity and mortality associated with SARS-CoV-2 has accelerated the development of many potential vaccines. However, these vaccines are designed against SARS-CoV-2 isolated in Wuhan, China, and thereby may not be effective against other SARS-CoV-2 variants such as the United Kingdom variant (VUI-202012/01). The UK SARS-CoV-2 variant possesses D614G mutation in the Spike protein, which impart it a high rate of infection. Therefore, newer strategies are warranted to design novel vaccines and drug candidates specifically designed against the mutated forms of SARS-CoV-2. One such strategy is to target ACE2 (angiotensin-converting enzyme2)–Spike protein RBD (receptor binding domain) interaction. Here, we generated a homology model of Spike protein RBD of SARS-CoV-2 UK strain and screened a marine seaweed database employing different computational approaches. On the basis of high-throughput virtual screening, standard precision, and extra precision molecular docking, we identified BE011 (Dieckol) as the most potent compounds against RBD. However, Dieckol did not display drug-like properties, and thus different derivatives of it were generated in silico and evaluated for binding potential and drug-like properties. One Dieckol derivative (DK07) displayed good binding affinity for RBD along with acceptable physicochemical, pharmacokinetic, drug-likeness, and ADMET properties. Analysis of the RBD–DK07 interaction suggested the formation of hydrogen bonds, electrostatic interactions, and hydrophobic interactions with key residues mediating the ACE2–RBD interaction. Molecular dynamics simulation confirmed the stability of the RBD–DK07 complex. Free energy calculations suggested the primary role of electrostatic and Van der Waals’ interaction in stabilizing the RBD–DK07 complex. Thus, DK07 may be developed as a potential inhibitor of the RBD–ACE2 interaction. However, these results warrant further validation by in vitro and in vivo studies.