Estimating Nutrient Uptake Requirements for Melon Based on the QUEFTS Model

Imbalanced and excessive fertilizer application has resulted in low yields and reduced nutrient use efficiency for melon production in China. Estimating nutrient requirements is crucial for effectively developing site-specific fertilizer recommendations for increasing yield and profit while reducing negative environmental impacts. Relationships between the yield and nutrient uptake requirements of above-ground dry matter were assessed using 1127 on-farm observations (2000–2020) from melon production regions of China. The quantitative evaluation of fertility of tropical soils (QUEFTS) model was used to estimate nutrient requirements. It predicted a linear increase in yield at balanced nutrient uptake levels until the yield reached approximately 60–80% of the potential yield. In order to produce 1000 kg of fruit, 2.9, 0.4 and 3.2 kg/ha of N, P and K (7.2:1.0:7.8), respectively, were required for above-ground parts, while the corresponding nutrient internal efficiencies were 345.3, 2612.6 and 310.0 kg per kg N, P and K, respectively, whereas 1.4, 0.2 and 1.9 kg of N, P and K were required to replace nutrients removed after harvest. The corresponding fruit absorption rates were 47.0%, 59.5% and 58.2%, respectively. Field validation experiments confirmed the consistency between observed and simulated uptake rates, indicating that this model could estimate nutrient requirements. These findings will help develop fertilizer recommendations for improving melon yield and nutrient use efficiency.

Understanding Nutrition and Metabolism of Threatened, Data-Poor Rheophilic Fishes in Context of Riverine Stocking Success-Barbel as a Model for Major European Drainages?

Large-bodied, river-migrating, rheophilic fishes (cyprinids) such as barbel Barbus barbus, nase Chondrostoma nasus, asp Leuciscus aspius, and vimba bream Vimba vimba are threatened in major European drainages. This represents the subject of our present study. Their hatchery nutrition prior to river-release is mostly on a hit-and-trial or carp-based diet basis. The study demonstrates an alternative approach to decide optimum nutrition for these conservation-priority and nutritionally data-poor fishes. The study revealed barbel as a central representative species in terms of wild body composition among other native rheophilic cyprinids considered (asp, nase, vimba bream). Taking barbel as a model, the study shows that barbel or rheophilic cyprinids may have carnivorous-like metabolism and higher requirements of S-containing, aromatic, branched-chain amino acids (AAs) than carps. Besides, there are important interactions of AAs and fatty acids (FAs) biosynthesis to consider. Only proper feeding of nutritionally well-selected diets may contribute to river stocking mandates such as steepest growth trajectory (≈less time in captivity), ideal size-at-release, body fitness (≈blend-in with wild conspecifics, predator refuge), better gastrointestinal condition, maximized body reserves of functional nutrients, and retention efficiencies (≈uncompromised physiology). Considering important physiological functions and how AA–FA interactions shape them, hatchery-raised fishes on casually chosen diets may have high chances of physiological, morphological, and behavioral deficits (≈low post-stocking survivability). Based on the observations, optimum nutrient requirements of juvenile (0+ to 1+ age) barbels are suggested. Future efforts may consider barbels as a nutrition model for conservation aquaculture of threatened and data poor rheophilic cyprinids of the region.

CyanoHABs: unavoidable evolutionary ecological consequence for low nutrient-requiring cyanobacteria in eutrophic water

The mechanism of cyanobacterial harmful algal blooms (CyanoHABs) is complicated and confusing. One major reason is they are studied primarily from an ecological perspective and on bloom-forming species only. This narrow angle loses a broader evolutionary and ecological context in which CyanoHABs occur and fails to provide information on relevant components to achieve a wholistic understanding. To derive a comprehensive mechanism of CyanoHABs, we examine CyanoHABs through the overlooked evolutionary and ecological lenses: evolutionary radiation, ecological comparison with co-living algae, and recently identified genomic functional repertoire between blooming and non-blooming species. We found key factors: (1) elaborate diverse functional repertoire and low nutrient requirement in cyanobacteria molded by early adaptive evolution, (2) cyanobacteria having lower nutrient requirements than green algae indeed, (3) there is no directed evolution in biological functions toward water eutrophication in cyanobacteria, (4) the CyanoHAB-associated functional repertoire are more abundant and complete in blooming than non-blooming species. These factors lead us to postulate a preliminary mechanism of CyanoHABs as a synergistic quad: superior functional repertoire, established with long adaptive radiation under nutrient-deficient conditions and not evolved toward eutrophic conditions, enables cyanobacteria to efficiently utilize elevated nutrients under current eutrophic regime for excess growth and CyanoHABs thereof, due to their lower nutrient requirements than co-living algae. This preliminary synthesis without doubt needs further empirical testing, which can be undertaken with more comparative studies of multiple species using integrated systems biology approaches.

The growth response and shallot production on some dosage of npk nitrate compound fertilizer 16-16-16

Fertilizer is considered to be one of the important factors in increasing shallot production. However, this must be followed by proper fertilization management to meet the nutrient requirements of the plant. This research was conducted with the aim of dertermining the correct dosage of NPK 16:16:16 based on ammonium nitrate in shallot plants. The assessment was carried out in October-December 2018. The research was carried out at one of the centers of shallot development, specificallly in Batu Rampung Hamlet, Tanete Village, Angeraja Sub-District, Enrekang Regency, South Sulawesi. A randomized block design (RBD) was used in this research, accompanied by three replications and eight treatments: P1 = NPK Nitrate 16-16-16 450 kg/ha + Urea 150 kg/ha + ZA 300 kg/ha; P2 = NPK Nitrate 16-16-16 400 kg/ha + Urea 150 kg/ha + ZA 300 kg/ha; P3 = NPK Nitrate 16-16-16 350 kg/ha + Urea 150 kg/ha + ZA 300 kg/ha; P4 = NPK Nitrate 16-16-16 900 kg/ha; P5 = NPK Nitrate 16-16-16 800 kg/ha; P6 = NPK Nitrate 16-16-16 700 kg/ha; P7 = Urea 200 kg/ha + ZA 400 kg/ha + KCL 100 kg/ha; P8 = NPK Phonska 645 kg/ha + Urea 645 kg/ha + SP36 645 kg/ha. The results showed that NPK Nitrate Fertilization 16:16:16 at a dose of 700- 900 kg/ha indicated a fairly high growth and production (14.5-16.3 t/ha). The results obtained were not significantly different from the high-dose fertilization used by farmers (17.2 t/ha), and higher than the single dose based on the recommendation (12.8 t/ha).

Biomimetic cellulose-based superabsorbent hydrogels for treating obesity

In the treatment of obesity, nutritional and behavioral modifications are difficult to implement and maintain. Since vegetable consumption is a fundamental part of many dietary interventions and daily nutrient requirements, we developed a novel cellulose-based superabsorbent hydrogel (CB-SAH) platform, inspired by the composition and mechanical properties of raw vegetables, as a mechanobiological therapy. The CB-SAHs properties were studied in a simulated gastrointestinal environment, while their impact on gut tissue was investigated by an ex vivo organ culture (EVOC) model. Functional fibers and raw vegetables were used as reference. CB-SAHs demonstrated orders of magnitude higher elasticity in comparison to the tested functional fibers, however performed similar to the tested raw vegetables. Notably, the biomimetic CB-SAHs with elasticity levels similar to raw vegetables showed benefits in preserving and regulating the gut tissue in the EVOC model. Non-systemic oral mechanotherapeutics based on this technology were advanced through clinical studies, with a first product cleared as an aid for weight management in the US and Europe.

Problems of unification of fodder quality and nutritive value assessment systems

The article is devoted to the urgent need for improvement and unification of systems for the quality evaluation of feed and rations. Lack of uniform sampling methods, analysis methods, feed quality indicators; norms of the nutrient requirements depending on the physiological state of animals, a unified approach to balancing diets, and most importantly - the absence of an international standard system for assessing the energy nutritive value of feed and rations - complicates the mutual understanding of scientists and practitioners from different countries and the integration of scientific achievements into agricultural production.

Zoometric Characterization of Creole Cows from the Southern Amazon Region of Peru

Bovine breeding began in Peru more than five centuries ago; since then, adaptation has started. Nowadays, Creole cattle are part of economic activities of Peruvian farmers, as they supply food and profits, among other things, for families in Andean region. Creole cattle have many strengths such as resistance to diseases, low nutrient requirements and easy adaptation to different levels of altitude and environmental conditions. However, even with all these attributes, they are not valued within production systems. Moreover, these valuable genetic resources are disappearing gradually in Perú. For this reason, this study aims to characterize the zoometry of Creole cows from the Southern Amazonas region of Peru. Biotype classification was performed by hierarchical cluster and multivariate factors analysis. Qualitative traits were analyzed with descriptive statistics and Duncan’s test (α = 0.05) was used to compare means among groups. Associations between qualitative traits were determined with Chi-square. We distinguished three biotypes of Creole cows with characteristics for meat and milk production. This information is helpful for future conservation programs for Creole cattle.

525 Late-Breaking: Late Gestational Nutrient Restriction of Primiparous Beef Heifers Decreases Milk Yield and Pre-weaning Calf Growth

Fall-calving Hereford-SimAngus heifers (single-sired; BW: 451 ± 28 [SD] kg; BCS: 5.4 ± 0.7) bred to a single sire were individually-fed 100% (control; CON; n = 12) or 70% (nutrient restricted; NR; n = 13) of NASEM net energy and metabolizable protein requirements for maintenance, pregnancy, and growth from d 160 of gestation to calving. Post-calving, all females were limit-fed chopped tall-fescue hay supplemented to meet lactational nutrient requirements in Calan gates to constrain calves’ diets to milk only until d 147. Four-hour milk yields were measured 5 times; calf size was determined every 21 d. Data were analyzed with treatment, calving date, and calf sex (when P < 0.25) as fixed effects; day and day x treatment were included for milk yield. From calving to d 147, CON cows had greater (P ≤ 0.003) BW, BCS, and backfat, but NR cows gained more (P ≤ 0.004) BW, BCS, and backfat. Milk weight and volume was 15% less (main effect; P < 0.04) for NR cows. Calf size did not differ at birth (P ≥ 0.27). From d 42 to 147, calves born to NR dams had lower (P ≤ 0.02) BW. Heart, abdominal, and flank girths were less (P ≤ 0.07) for NR calves through d 147. Calf ribeye area tended to be less (P ≤ 0.11) in NR calves at d 42, 84, and 126. Nutrient restricted calves had less shoulder to rump length (d 63 to 147; P ≤ 0.08), shoulder height (d 63 to 126; P ≤ 0.02), cannon length (d 42 to 105 and 147; P ≤ 0.09), and cannon circumference (d 63 and 105 to 147; P ≤ 0.06). These data indicate that even when dams are fed to meet lactational requirements, milk yield and calf growth are reduced by late gestational nutrient restriction.