Abstract Consumers mediate nutrient cycling through excretion and egestion across most ecosystems. In nutrient‐poor tropical waters such as coral reefs, nutrient cycling is critical for maintaining productivity. While the cycling of fish‐derived inorganic nutrients via excretion has been extensively investigated, the role of egestion for nutrient cycling has remained poorly explored. We sampled the fecal contents of 570 individual fishes across 40 species, representing six dominant trophic guilds of coral reef fishes in Moorea, French Polynesia. We measured fecal macro‐ (proteins, carbohydrates, lipids) and micro‐ (calcium, copper, iron, magnesium, manganese, zinc) nutrients and compared the fecal nutrient quantity and quality across trophic guilds, taxa, and body size. Macro‐ and micronutrient concentrations in fish feces varied markedly across species. Genera and trophic guild best predicted fecal nutrient concentrations. In addition, nutrient composition in feces was unique among species within both trophic guilds (herbivores and corallivores) and genera (AcanthurusandChaetodon). Particularly, certain coral reef fishes (e.g.,Thalassoma hardwicke,Chromis xanthura,Chaetodon pelewensisandAcanthurus pyroferus) harbored relatively high concentrations of micronutrients (e.g., Mn, Mg, Zn and Fe, respectively) that are known to contribute to ocean productivity and positively impact coral physiological performances. Given the nutrient‐rich profiles across reef fish feces, conserving holistic reef fish communities ensures the availability of nutritional pools on coral reefs. We therefore suggest that better integration of consumer egestion dynamics into food web models and ecosystem‐scale processes will facilitate an improved understanding of coral reef functioning.
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Analysis of Nutrient Profile of Finger Millet (Eleusine coracana (L.) Gaertn.) for Baby Food Formulation Using Pigeon Pea (Cajanus cajan (L.) Millsp.) as Protein Source
Finger millet (Eleusine coracana (L.) Gaertn.) is a drought resistant crop with potentially tremendous but under-explored source of nutraceutical properties as compared to other regularly consumed cereals in the era of drawback of nutritional security, these characteristics must be harnessed to develop finger millet as a novel functional food. Under-nutrition caused by inadequate diets, and other factors that influence nutritional status, is the underlying factor in 45% child deaths. In Kenya only 25% of young children are fed adequately diverse diets. The main objective of this study was to prepare baby food formulas using finger millets with pigeon peas as protein source and to analyze their nutritional profiles. Two finger millets varieties (i) Snapping Green Early, low altitude and medium altitude varieties and (ii) U-15) were studied to determine effects of environment on nutrient profiles. This study showed that Snapping Green Early had better nutrient profiles (12.13% protein and is high in Ca, Mg, Fe, Zn and P) than U-15 (11.69% protein and lower nutrients (Ca, Mg, Fe, Zn and P)), and hence was selected for use in the malting process as best variety. As expected, the pigeon peas had the highest protein value (21%). The samples malted for 72 h resulted in reduction of tannin concentration from 0.091% to 0.03% and the amount of nutrients (Ca, Mg, Fe and Zn) doubled and in fact the protein profile increased by 8.31%. The appropriate ratio for the formulation of the baby food was 70:30. The composting resulted in 18.5% increase in protein.
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- Award ID(s):
- 1757607
- PAR ID:
- 10316055
- Date Published:
- Journal Name:
- Journal of agricultural science and technology
- Issue:
- 10
- ISSN:
- 2161-6264
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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