Potential Food Sources Research Articles

Effects of Land Application of Farm Dairy Effluent on The Growth of Sweet Corn

This study investigates the impact of land application of farm dairy effluent (FDE) on the growth and yield of sweet corn (Zea mays var. saccharata). The agricultural sector faces increasing challenges in managing effluents sustainably, and the utilization of FDE as a potential nutrient source for crop production has gained prominence. Field experiments were conducted to assess the effects of FDE application on sweet corn with different rate of irrigation. Randomized completely block design was used an experimental design with different irrigation rate i.e. A = 0% FC effluent, B = 25% FC effluent, C = 50% FC effluent, D = 75% FC effluent, and E = 100% FC. The collected data was analyzed by using ANOVA with 5% of significance, a further test is performed using duncan multiple range test. The results showed that FDE had TDS, TSS, BOD and COD higher than the standard with values ​​of 1398 mg/L, 2575 mg/L, 3611 mg/L and 6374 mg/L respectively. The application of FDE significantly influenced sweet corn growth especially on height and leaf increment. The application of FDE with 100% FC tends to have higher leaf increment than other treatments at 35 DAA (day after application).

Assessing nutritional and genetic variations within foxtail millet (Setaria italica) landraces collected from indigenous communities across the Philippines

Unknown to many, the Philippines is host to a few remaining accessions of the underutilised and understudied cereal foxtail millet (Setaria italica (L.) P. Beauv.). We collected together accessions of this crop from different eco-geographical locations within the Philippines, along with a few accessions from Lanyu, Taiwan, to undertake a study of their nutritional value and genetic diversity. All accessions were field-grown in 2022, dry season (DS) at the Institute of Plant Breeding (IPB) Experiment Station, Los Baños, Laguna, Philippines. The accessions were tested for micronutrients, including Zn and Fe, nitrogen as a proxy for protein, β-carotene, phytic acid, and a number of phenolic compounds with known nutritional potential. Of the 20 accessions tested, the accessions Bayaras and GB61438 had the highest level of Zn (107.1 mg/kg) and Fe (70.52 mg/kg), respectively, higher than levels found in traditional rice varieties. For β-carotene the highest concentration was found in the accession Balles (∼10 μg/g). Twelve phenolic compounds were detected, with catechin, syringic acid, ferulic acid and kaempferol having the highest concentrations. To assess the genetic diversity, we sequenced a set of eight samples selected from among the accessions to a depth of at least 25-fold using whole-genome re-sequencing. Analysis of the population structure, using genome-wide, high-quality SNPs, showed modest diversity among the accessions, with two unadmixed groups. The accessions are monophyletic relative to their earliest common ancestor, with the very light brown accessions emerging earlier than the light brown and reddish-brown varieties. Analysis of zinc-regulated, iron-regulated transporter-like protein (ZIP) transporters within the foxtail millet reference sequence, var. Yugu1 identified 17 putative ZIP transporters. Variant calling identified SNPs primarily within 3′ and 5’ regions, and introns, indicating variation between foxtail millet accessions within regulatory gene regions rather than in structural proteins. The local foxtail millet accessions, therefore, represent a potential alternative source of nutrients which may help in addressing malnutrition in the Philippines.

Education on the Potential of Fish Nutrients to Coastal Housewives in Leppe Village

Fish is one of the potential food sources of animal protein produced in coastal areas. The use of fish as a source of animal food by coastal communities has been carried out for generations because it is the easiest food source to be processed into daily side dishes for coastal households. Fish contains quality nutrients, both macronutrients and micronutrients. The condition of coastal housewives who lack information about the nutritional content of fish and its benefits is the background for implementing this community service activity. The aim of the activity is to increase the knowledge of coastal communities, especially housewives, so that they can utilize the nutritional potential of fish through the processing and consumption of fish to fulfill the family's nutritional intake.Coastal housewives were very enthusiastic during the activity which was marked by answering several questions in the question and answer process. The results of the evaluation showed that education can provide an understanding of fish nutrition and its benefits, where the percentage of correct answers reached 94.54%. Coastal housewives are expected to be able to utilize the nutritional potential of fish which is a source of quality animal food that is easily obtained in coastal areas.

Color Stability and Antioxidant Activity of Red Roselle (Hibiscus Sabdariffa L.) Calyx Infuse

The roselle flower (Hibiscus sabdariffa L.), is known as a potential functional food source because of its antioxidant and antibacterial properties. Apart from that, it is also used as a natural dye because of its red color. Antioxidant compounds in roselle flowers include neo-chlorogenic acid, chlorogenic acid, cryptochlorogenic acid, routine, and isoquercitrin. The high content of these antioxidant compounds often causes color instability. For this reason, this research will analyze the effect of temperature and long storage on color changes and the antioxidant activity of a red roselle flower infusion. Storage conditions are carried out with three temperature variations, namely cold temperature (2–8 oC), cool temperature (8–15 oC), and room temperature (15–30oC), with a long storage of 8 days. The stability parameters used are color changes and activity as an antioxidant. Color changes were measured using a chromameter, while the antioxidant activity was measured by the IC50 value using the DPPH method. The principle of this method is that a purple color change reaction based, which fades, and then the inhibitory intensity against DPPH is measured using UV-Vis spectrophotometer. It was found that the color values have significant differences visible from the first day storage at the room temperature (30oC), cool temperature (11oC), and cold temperature (6 oC). So, there was an influence of temperature and long storage on the color change of boiled red roselle flower calyx. A significant decrease in activity was seen on the first day storage at room temperature (30 oC) and third day storage at cool temperature (11 oC). Meanwhile, at cold temperatures (6 oC), there was no significant effect on the reduction in activity from boiling red roselle flower calyx for up to 8 days of storage

The temporal-spatial expression and functional analysis of three gustatory receptor genes in Solenopsis invicta using sweet and bitter compounds.

The insect gustatory system participates in identifying potential food sources and avoiding toxic compounds. During this process, gustatory receptors (GRs) recognize feeding stimulant and deterrent compounds. However, the GRs involved in recognizing stimulant and deterrent compounds in the red imported fire ant, Solenopsis invicta, remain unknown. Therefore, we conducted a study on the genes SinvGR1, SinvGR32b, and SinvGR28a to investigate the roles of GRs in detecting feeding stimulant and deterrent compounds. In this current study, we found that sucrose and fructose are feeding stimulants and the bitter compound quinine is a feeding deterrent. The fire ant workers showed significant behavior changes to avoid the bitter taste in feeding stimulant compounds. Reverse transcription quantitative real-time polymerase chain reaction results from developmental stages showed that the SinvGR1, SinvGR32b, and SinvGR28a genes were highly expressed in fire ant workers. Tissue-specific expression profiles indicated that SinvGR1, SinvGR32b, and SinvGR28a were specifically expressed in the antennae and foreleg tarsi of workers, whereas SinvGR32b gene transcripts were also highly accumulated in the male antennae. Furthermore, the silencing of SinvGR1 or SinvGR32b alone and the co-silencing of both genes disrupted worker stimulation and feeding on sucrose and fructose. The results also showed that SinvGR28a is required for avoiding quinine, as workers with knockdown of the SinvGR28a gene failed to avoid and fed on quinine. This study first identified stimulant and deterrent compounds of fire ant workers and then the GRs involved in the taste recognition of these compounds. This study could provide potential target gustatory genes for the control of the fire ant.

Phenolic Constituents from Black Quinoa Alleviate Insulin Resistance in HepG2 Cells via Regulating IRS1/PI3K/Akt/GLUTs Signaling Pathways.

Quinoa is a nutrient-rich pseudocereal with a lower glycemic index and glycemic load. However, its therapeutic potency and underlying mechanism against insulin resistance (IR) have not been fully elucidated. In this work, network pharmacology was applied to screen IR targets and their related pathways. The efficacy and mechanism of black quinoa polyphenols (BQP) on IR improvement were evaluated and uncovered based on the IR model in vitro combined with molecular docking. Ten phenolic constituents of BQP were detected, and the network pharmacology results show that PI3K/Akt pathways are the main pathways in BQP against IR. The in vitro assay proved that BQP increases the glucose consumption and glycogen synthesis via upregulating insulin receptor substrate 1 (IRS1)/PI3K/Akt/glucose transporters (GLUTs) signaling pathways to alleviate IR. Rutin, resveratrol, and catechin show lower binding energy docking with IRS1, PI3K, Akt, and GLUT4 proteins, indicating better interactions. It might be an effective constituent against IR. Hence, BQP could become a potential functional food source for blood glucose management among insulin-resistant people.

Insect frass as a fertilizer for the cultivation of protein-rich Chlorella vulgaris

Replacing the large amounts of chemical fertilizer with nutrients from waste or residual streams is an important factor to make microalgal production more sustainable, cost-effective, and part of a circular bioeconomy. This is the first study to investigate insect frass as a potential nutrient source for microalgal cultivation, and its effect on the protein content of the microalgae Chlorella vulgaris. When grown on nutrients extracted from insect frass, C. vulgaris grew equally well and showed similar high protein content (40 % of the dry weight) as when grown in a control medium based on commercial fertilizers. The nitrogen in the frass media consisted predominantly of organic nitrogen compounds, of which 71–78 % could be consumed by the microalgae. While the presence of dissolved organic carbon in the insect frass promoted the growth of algae-associated bacteria, microalgal performance was not affected.

Comparative GC–MS based nutrients profiling of less explored legume seeds of Melilotus, Medicago, Trifolium, and Ononis analysed using chemometric tools

Exploring novel sources of plant protein for nutrition of both humans and animals is motivated mainly by its growing demand worldwide, besides identifying healthy alternatives for animal protein. The present study evaluates metabolome diversity within 15 legume seed species. The examined samples comprised three Melilotus, four Medicago, four Trifolium, and four Ononis seed species. A holistic approach for metabolites profiling using gas chromatography-mass spectrometry (GC–MS) led to the annotation and quantification of 87 metabolites comprising alcohols, free amino acids, aromatics, fatty acids/esters, nitrogenous compounds, organic acids, sugar alcohols, sugars, terpenes, and steroids. Fatty acids represented the major metabolite class represented by palmitic, stearic, oleic, linoleic, and linolenic acids. Sucrose and pinitol were the major sugars and sugar alcohols among seeds. Ononis seeds (OR, OS and OA) were the most abundant in fatty acids, sugars, sugar alcohols, and free amino acids, whereas Melilotus species (MO and MS) were least enriched in these key nutrients posing Ononis as potential food source for humans and animals. The examined seeds were generally low in sulfur-containing free amino acids and lacking many of the essential free amino acids. Multivariate data analysis aided in the identification of Ononis metabolite markers belonging to various classes i.e., (alcohol) glycerol, (sugar) allofuranose, and (sugar alcohol) pinitol, although the differentiation between Medicago, Melilotus, and Trifolium genera was not attained suggestive for other analytical platforms for its classification.

DNA metabarcoding focused on difficult-to-culture protists: An effective approach to clarify biological interactions.

DNA metabarcoding on a single organism is a promising approach to clarify the biological interactions (e.g., predator-prey relationships and symbiosis, including parasitism) of difficult-to-culture protists. To evaluate the effectiveness of this method, Radiolaria and Phaeodaria, which are ecologically important protistan groups, were chosen as target taxa. DNA metabarcoding on a single organism focused on the V9 region of the 18S rRNA gene revealed potential symbionts, parasites and food sources of Radiolaria and Phaeodaria. Previously reported hosts and symbionts (parasites) were detected, and newly recognized combinations were also identified. The contained organisms largely differed between Radiolaria and Phaeodaria. In Radiolaria, members of the same order tended to contain similar organisms, and the taxonomic composition of possible symbionts, parasites, and food sources was fixed at the species level. Members of the same phaeodarian family, however, did not contain similar organisms, and body part (i.e., the central capsule or the phaeodium) was the most important factor that divided the taxonomic composition of detected organisms, implying that the selection of appropriate body part is important when trying to ascertain contained organisms, even for unicellular zooplankton. Our results show that DNA metabarcoding on a single organism is effective in revealing the biological interactions of difficult-to-culture protists.

Chemolithoautotrophic Organic Matter Contributions to Subterranean Food Webs Dominated by Filter-feeders

Chemolithoautotrophic Organic Matter Contributions to Subterranean Food Webs Dominated by Filter-feeders

3000 Years of past regional and local land-use and land-cover change in the southeastern Swedish coastal area: Early human-induced increases in landscape openness as a potential nutrient source to the Baltic Sea coastal waters

Reconstructions of past land use and related land-cover changes at local and regional scales are needed to evaluate the potential long-term impacts of land use on the coastal waters of the Baltic Sea. In this purpose, we selected the Gamleby area at the Swedish Baltic Sea coast for a case study. We use a new, high resolution pollen record from a small lake (Lillsjön) located 3.6 km NNW of the bay Gamlebyviken and detailed analysis of the available archeological data to reconstruct local land-use changes over the last 3000 years. To estimate land-cover change at local (2–3 km radius area) and regional (50 km radius area) scales we use four additional, published pollen records from two small and two large lakes (25–70 km S of Lillsjön) and the Landscape Reconstruction Algorithm, a pollen-vegetation modeling scheme. Results show that regional and local (small lakes Lillsjön and Hyttegöl) land-cover changes are comparable over the last 1500 years (Late Iron Age to present), and that landscape openness was much larger locally than regionally (difference of 20–40% cover over the last 500 years). The periods of largest potential impacts on the Gamlebyviken Bay from regional and local land use are 200–950 CE (Late Iron Age) and 1450 CE to present, and of lowest potential impacts 950–1450 CE. The question on whether the large landscape openness 1150–50 BCE and significant afforestation 50 BCE–200 CE reconstructed for Lillsjön’s area are characteristic of the Gamlebyviken region will require additional pollen records in the catchment area.

Exhausted fire-extinguishing powders: A potential source of mineral nutrients for reuse and valorisation in compost enrichment for soilless cultivation

Fire-extinguishing powders (FEPs) are constituted by an inner mineral core of (NH4)H2PO4 and (NH4)2SO4 salts (>95 %, by weight) externally coated with Si-based additives, which make problematic reuse after their service life has expired (36 months). This study aimed to assess the feasibility of using the composting process as an environmentally friendly strategy to lyse the external coating and recycle this nutrient-rich solid waste for replacement of inorganic fertilization in soilless cultivation of horticultural crops. A microcosm-scale experiment with lettuce plants grown into a soil/quartz sand mixture under controlled conditions for 28 days was used to investigate plant responses (fresh and dry biomass, chlorophyll fluorescence parameters, root morphology, ash and nutrients content) to amendment with increasing dosages (equivalent at 0, 10, 20 and 30 t ha−1) of an exhausted FEPs-enriched compost. Chemical properties (pH, EC, TOC, TN) and content of soluble nutrients (Na+, K+, Mg2+, Ca2+, NH4+, H2PO4−, SO42−, NO3−, Cl−) released into the growing substrate were also monitored. Non-amended microcosms and non-enriched compost treatments were taken as controls. Results showed, beside the expected rise of phosphate, sulphate and ammonium ions, exhausted FEPs contributed Ca2+, Mg2+ and Na+ content. Whereas compost determined a dose-dependent release of K+, which was particularly useful in maintaining the K/Na ratio in a range not harmful to plant physiology. It was also found that the compost enriched with 5 % (w/w) exhausted FEPs was no phytotoxic to lettuce. On the contrary, it stimulated the plant growth, increased the photosynthetic efficiency and the shoot biomass accumulation, thus incrementing the shoot/root ratio. Moreover, it oriented the root morphology development and promoted the plant uptake of both water and solutes. To sum up, composting represents a suitable alternative to chemical treatment to recover readily available nutrients contained in exhausted FEPs and produce an enriched compost for use in soilless cultivation.

Antioxidant activity of palm kernel meal protein hydrolysate and characterization of its peptide profile

Palm kernel meal (PKM) is a major by-product of the palm oil industry, and its high protein content is a potential source of value-added functional food or feed. In this study, the total protein from PKM was isolated and hydrolyzed with alcalase enzyme (pH 7.5, 55oC) to obtain palm kernel protein hydrolysate. The results showed that PKM protein hydrolysate after 60 min of hydrolysis exhibited strong radical scavenging activity with IC50 values of 5.73±0.23 and 7.84±0.90 μg/mL as determined by 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), respectively. Furthermore, PKM protein hydrolysate was not toxic to mouse L929 fibroblast cells while protecting cells from H2O2-induced oxidative damage. Analysis of its peptide profile by liquid chromatography-mass spectrometry (LC-MS/MS) revealed nine peptide sequences with hydrophobic and negatively-charged amino acids with molecular weights ranging from 1,085.13 to 1,292.32 Da. Taken together, alcalase hydrolysate of PKM was found to have potent antioxidant and cytoprotective properties justifying further study for potential development as a functional food/feed.

Impact of organic liquid fertilizers on growth and yield performance of Green Bean (<em>Phaseolus vulgaris</em> L.) in non-circulating hydroponic system

Non-circulating hydroponic systems are a type of soilless production system that has been found to be extremely productive, low-cost, water, land efficient, and well-suited to avoid fertilizer leaching and groundwater contamination. The experiment was conducted to study the effect of liquid organic nutrient solutions on Green Bean (Phaseolus vulgaris L.) cultivation in non-circulating hydroponic system. The experiment was laid out in a Completely Randomized Design (CRD) with seven treatments having fifteen replicates. The treatments were recommended inorganic fertilizer application (T1), ½ doses of Albert’s solution with 0.5% vermiwash (T2), 1% vermiwash (T3), 1.5% vermiwash (T4), 0.5% vegetable waste solution (T5), 1% vegetable waste solution (T6), 1.5% vegetable waste solution (T7) was used as media. The results revealed that plant height, number of leaves and branches per plant, leaf area, dry weight of leaves and length of pods were significantly (P<0.05) varied at 6th week after planting and it was high in T5. However, number of pods per plant, girth of pods, fresh and dry weight of pods and yield were high in T2 at 3rd picking while yield at 1st and 2nd picking were high in T5. This result suggests that ½ doses of Albert’s solution with 0.5% vegetable waste solution (T5) and ½ doses of Albert’s solution with 0.5% vermiwash (T2) would be the potential source of plant nutrients for sustainable crop production of bean in Non-circulating Hydroponic system.

Identification of potential food sources affecting blood lead levels and their health hazards (CVD, respiratory diseases, cancer)

Environmental lead exposure is a well-known and significant public health concern. In areas with low lead exposure, comprehensive and detailed research and validation are needed to eliminate the adverse effects of environmental lead exposure. This study aims to understand the possible food pathways of environmental lead exposure by exploring the contribution of food to blood lead and the mediating effect of blood lead in the occurrence of diseases. Similarly, as lead is a heavy metal pollutant with good research foundation, fine analysis of lead in this period can also be a reference for other unknown pollutants. In this cross-sectional study of 1162 peoples, the data are taken from National Health and Nutrition Examination Survey (NANHES) 2015–2016, we grouped the population according to the median blood lead level (0.038 μmol/L) to screen the variables adjusted by the model. we grouped foods by code and used a generalized additive mixed model (GAMM) to study their relationship with blood lead levels, a correlation has been found between egg mixtures (p = 0.007) and legumes (p = 0.041) consumption and blood lead levels. We analyzed how metabolic status, exercise, and macronutrient intake modulate the impact of certain foods on blood lead levels to infer its possible process. To verify whether adverse effects are caused by lead, we explored the mediating effect of blood lead on the relationship between food intake and disease [cardiovascular diseases (CVD), respiratory diseases, cancer], however, no statistically significant mediating effect was found. Overall, environmental lead exposure through food still affects blood lead levels, but it has not led to adverse outcomes in blood, respiratory system, or cancers Under conditions where lead exposure levels were equivalent to those in the study (blood lead levels， mean = 0.052 μmol/L, standard deviation = 0.048 μmol/L, median = 0.038 μmol/L, min = 0.002 μmol/L, max = 0.904 μmol/L, skewness = 6.543, kurtosis = 89.391).

A study of the feeding characteristics of a small and medium-sized copepod species (Sinocalanus tenellus) using genetic analysis techniques: seasonal comparison of potential/eaten food sources focused on phytoplankton

In aquatic ecosystem, the food web structure based on composition and abundance of prey species influences the feeding characteristics of predators, resulting in changes to the structure and function of the entire food web. Zooplankton mainly feed on phytoplankton, but the method of analyzing the feed source through visual and microscopic identification of gut contents has limitations in applicable species and the low resolution of the analysis results. In this study, potential vs. eaten food sources of Sinocalanus tenellus, a small and medium-sized copepod species dominant in brackish waters, were analyzed based on phytoplankton operational taxonomic units detected from the habitat’s raw water and treated whole bodies of S. tenellus. The alpha diversity and dominant/subdominant species of each potential and eaten food source were identified, and they were compared across seasons. At the same time, the feeding selectivity index (Ei) was calculated by identifying overlapping species in the potential vs. eaten food source pool. As a result, it was confirmed that not all surrounding potential food sources are fed on by S. tenellus, and that its diet can vary depending on the presence/absence of preferred prey. Metabarcoding techniques is considered to be an effective way to identify fluctuations in major food sources of zooplankton at the genus or species level. If uncertainties such as incomplete species identification as identified from the results of this study are improved through improving of analysis methods such as application of species-specific primers in the future, it will be useful for securing information on the feeding characteristics of small to medium-sized zooplankton.

Understory management in apple cultivation and potential food sources for honey bees in the understory of apple orchards

Der Apfelanbau ist mittlerweile nicht mehr aus Südtirol wegzudenken. Auf rund 18.300 ha werden ca. 10 % der Äpfel auf dem europäischen Markt produziert. Da die Apfelanlagen in manchen Teilen der Region über 75 % der landwirtschaftlich genutzten Fläche einnehmen, haben sie auch einen Einfluss auf die dort vorkommende Fauna. So kann z.B. der blühende Unterwuchs von Insekten als Nahrungsquelle für Pollen und Nektar verwendet werden. Diese Studie beschäftigt sich mit dem Unterwuchsmanagement und dessen Auswirkungen auf die Vegetation in den Apfelanlagen. Es wird gezeigt, dass das Mulchen des Fahrstreifens, sowie Herbizidbehandlungen in den Baumreihen sehr wohl Auswirkungen auf die Unterwuchsvegetation haben, diese aber nur relativ kurzfristig sind und deshalb im richtigen Moment erfolgen müssen. Es ist zwar kaum möglich alle Blüten aus dem Unterwuchs zu entfernen. Totzdem kann durch das richtige Management der Vegetation der Anreiz für Bestäuber in die Anlagen zu fliegen, und somit das Risiko, dass sie mit Pflanzenschutzmitteln in Kontakt kommen, minimiert werden.

Chemometric approach for an application of Atlantic salmons (Oncorhynchus keta) by-product for potential food sources.

This study identified the aroma profile of salmon by-product for high utilization of by-products, including hydrolysates of head, frame, and skin were treated with reducing sugars and thermal processing. Electronic nose (E-nose) and gas chromatography-mass spectrometry (GC-MS) coupled with gas chromatography-olfactometry (GC-O) were used to analyzed the aroma profile. A total of 140 and 90 volatile compounds were detected through E-nose and GC-MS respectively, and the main volatile compounds were aldehydes. A total of 23 odor active compounds were recognized using GC-O, and 3-methyl-butanal, heptanal, benzaldehyde, octanal, furfural, and methoxy-phenyl-oxime were identified as the aroma of salmon. Using multivariate analysis, the pattern between the pretreated samples and aroma profiles was confirmed, and there were clear separations among the samples. The results of this study provide the aroma profile of salmon by-products and are expected salmon by-products to be used as a potential food source.

Proximate Analysis of Unconventional Feed Available in Boalkhali Upazila, Chattogram

The study was conducted to evaluate the nutritional status of unconventional feed resources (UCFR) available in the Chattogram district. Unconventional feed resources refer to all those feeds that have not been traditionally used in another feeding and or are not normally used in commercially produced rations for livestock and poultry. A total of four tree leaves namely Jackfruit (Artocarpus heterophyllus), Mango (Mangifera indica), Banyan (Ficus benghalensis), and Mandar (Erythrina fusca) were considered for proximate analysis in the Animal Nutrition Laboratory, Department of Animal Science and Nutrition, Chattogram Veterinary and Animal Sciences University, Bangladesh. The laboratory analysis was performed according to the standard analytical procedure of the Association of Official Analytical Chemists (AOAC). The results indicated that the highest Dry mater (DM %) was in Jackfruits leaves whereas the lowest Dry matter (DM %) was in Mandar leaves. The highest Moisture % was in Mandar leaves whereas the lowest Moisture % was in Jackfruits leaves. The highest Crude protein (CP %) was in Mandar leaves whereas the lowest Crude protein (CP %) was in Mango leaves. The highest Crude fiber (CF %) was in Mandar leaves whereas the lowest Crude fiber (CF %) was in Banyan leaves. The highest Ether extract (EE%) was in Mango leaves whereas the lowest Ether extract (EE%) was in Jackfruit leaves and the highest Total Ash (TA%) was in Banyan leaves whereas the lowest Total Ash (TA%) was in Mandar leaves. In conclusion, the nutritional status of all tree leaves showed a higher Crude protein, Crude fiber, Ether extract, and Total Ash content. Therefore, these tree leaves can be used as a potential source of nutrients in livestock and poultry feed as well.

Stable isotope values and trophic analysis of invasive three-spined stickleback in Upper Lake Constance points to significant piscivory

The three-spined stickleback Gasterosteus aculeatus was introduced into Lake Constance in the 1940s and occupied a limited range until late 2012. Since then the species has expanded from a solely littoral habitat in Upper Lake Constance, but now makes seasonal migrations into the pelagic zone. This behavioral change has been accompanied by a drastic increase in stickleback abundance. In order to integrate information about feeding of sticklebacks in Upper Lake Constance over two consecutive years, stomach content analysis was combined with seasonal stable isotope analysis on two types of tissue (muscle and liver). Isotope values were also obtained for zooplankton, whitefish larvae and eggs. We calculated the contribution of potential food sources for sticklebacks’ diet using a Bayesian mixing model (SIMMR). Furthermore, we determined stickleback trophic position, and δ15N and δ13C values were compared with those of other fish species of Lake Constance. The results of the Bayesian model as well as the stomach content analysis showed clear evidence of stickleback predation on fish eggs and larvae. Stickleback δ15N values were elevated during winter and comparable to those of piscivorous pike, while δ15N values of zooplankton were reduced, and those of whitefish larvae were similar to those of sticklebacks after accounting trophic fractionation of N isotopes. Trophic position calculations further identified sticklebacks as piscivorous, while the δ13C values of the liver and stomach content analysis suggests that a benthic-pelagic species pair may exist in Lake Constance. These findings support the hypotheses that sticklebacks in Lake Constance can display piscivorous feeding behaviour on sympatric fish species, most likely whitefish larvae and eggs.