scholarly journals Nitrogen and phosphorus dynamics in Nile tilapia farming in excavated rearing ponds

2020 ◽  
Vol 9 (11) ◽  
pp. e1319119699
Author(s):  
Anderson Coldebella ◽  
Antonio Cesar Godoy ◽  
André Luis Gentelini ◽  
Pitágoras Augusto Piana ◽  
Priscila Ferri Coldebella ◽  
...  
Keyword(s):  
Dry Matter ◽  
Management Practices ◽  
Production Cycle ◽  
Harvest Time ◽  
Nitrogen And Phosphorus ◽  
New Production ◽  
Feed Composition ◽  
Nutritional Recommendations ◽  
Harvesting Process ◽  
Supply Water

The purpose of this study was to determine the total nitrogen (TN) and total phosphorus (TP) balance during intensive tilapia farming in excavated ponds. To quantify TN and TP released into the environment, the supply water, effluents at the harvest time, fish composition, feed, and sediment were analysed. The mass balance between the amount of nutrients that is inserted through the feed, which is transformed into biomass by the fish and is retained in the sediment was calculated based on dry matter. The nutrient load arriving from the supply water was calculated as a function of the concentration of TN and TP. The TN and TP dynamics during the harvesting process in three different pond sizes identified that, on average, 2.37% of TN and 2.05% of TP inserted into the system during rearing is eliminated with 10.64% TN and 37.01% TP are retained in the sediment. The TN and TP input into the system occurs through the water supply, young fish, and the feed, the latter being responsible for about 92.87% TN and 96.05% TP. The feed composition indicates that the P level of the food is above the nutritional recommendations for the species. The amount of TP accumulated in the sediments indicates that there is a need for good management practices for water quality during the rearing and sediment management period before the beginning of a new production cycle.

scholarly journals LED Intercanopy Lighting in Blackberry During Spring Improves Yield as a Result of Increased Number of Fruiting Laterals and Has a Positive Carryover Effect on Autumn Yield

2021 ◽  
Vol 12 ◽  
Author(s):  
Anabel Rivas ◽  
Kang Liu ◽  
Ep Heuvelink
Keyword(s):  
Dry Matter ◽  
Management Practices ◽  
Market Price ◽  
Yield Component ◽  
Fruit Yield ◽  
Economic Feasibility ◽  
Production Cycle ◽  
Limiting Factor ◽  
Dry Matter Content ◽  
Carryover Effect

High market price and low availability of local winter and spring production has stimulated production of blackberries in glasshouses at northern latitudes. For this production, light is the main limiting factor. We investigated the potential of intercanopy lighting (ICL) using light emitting diodes (LEDs) to improve blackberry fruit yield in a crop with a spring and an autumn production cycle. During the spring production cycle three light treatments were applied: only natural light (no ICL), 93 or 185 μmol m–2 s–1 ICL In summer the lateral shoots were cut back and 93 μmol m–2 s–1 ICL was applied to all plants after cutting back, investigating a possible carryover effect of supplemental light in spring on autumn production. Fresh fruit yield in spring increased by 79 and 122% with 93 and 185 μmol m–2 s–1 ICL, respectively, compared to no ICL. This represents 3.6 and 2.8% increase in harvestable product for every additional 1% of light. A yield component analysis and leaf photosynthesis measurements were conducted. Maximum photosynthetic capacity (Amax) for leaves at 185 μmol m–2 s–1 ICL was about 50% higher, and LAI was 41% higher compared to no ICL. ICL increased the number of fruiting laterals per cane, and this explained 75% of the increase in yield. ICL at 185 μmol m–2 s–1 resulted in a higher yield compared to no ICL, primarily as a result of higher total dry matter production. Furthermore, a higher fraction of dry matter partitioned to the fruits (0.59 compared to 0.52) contributed to yield increase, whereas fruit dry matter content and fruit quality (sugar and acid content) was not affected by ICL. Averaged over the three light treatments autumn yield was 47% lower than spring yield. Autumn yield was 10% higher for plants at ICL 93 μmol m–2 s–1 in spring and 36% higher for plants at 185 μmol m–2 s–1 in spring compared to no ICL in spring. This increased autumn yield was caused by more fruiting laterals (less necrotic buds). It is concluded that management practices in spring can have a carryover effect on the autumn production. This is the first scientific paper on the potential for applying LED ICL in blackberries. Further research should focus on optimal intensity of ICL, positioning of supplementary lighting and economic feasibility.

scholarly journals Tactical decisions of concentrate level, slaughter age and carcass weight of bulls of five beef breeds under Norwegian conditions

2008 ◽  
Vol 19 (2) ◽  
pp. 101 ◽  
Author(s):  
H. BONESMO ◽  
L. NORDANG ◽  
L. DAVIES
Keyword(s):  
Dry Matter ◽  
Management Practices ◽  
Live Weight ◽  
Energy Concentration ◽  
Net Energy ◽  
Beef Production ◽  
New Production ◽  
Daily Return ◽  
Slaughter Age ◽  
Concentrate Level

Beef production based on suckler cow breeds is a relatively new production system in Norway as in most Nordic countries. To ensure the continuation of this production, profitable management practices designed for Norwegian conditions have to be established. Thus a simulation model was developed that integrates the daily feed intake, the daily live weight (LW) gain, silage net energy concentration for beef production (feed units beef (FUb) kg?1 dry matter) and price, concentrate level and price, and carcass price for bulls of the country's five most common beef breeds. In this work the model was combined with production statistics to find general recommendations in the finishing of beef bulls under Norwegian conditions. Among all the five breeds the Limousin bulls had the highest estimated mean daily return and the Hereford bulls the lowest estimated mean daily return from 20 g concentrate kg?1 LW0.75 for the 940 FUb kg?1 silage dry matter, and from 40 g concentrate kg?1 LW0.75 for the 800 FUb kg?1 silage dry matter. Our estimated optimal slaughter ages and carcass weights shows that it pays to more intensively feed during the finishing period for all five breeds. Current farming practice in Norway for the five major breeds studied is that slaughter age is at least two months later with lighter carcass weights than the results expected from following our model estimated recommendations.

scholarly journals 43 Nutritional management for tropical-subtropical-adapted cattle receiving high-concentrate diets

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 33-34
Author(s):  
Madeline Rivera ◽  
Jordan Adams ◽  
Luis O Tedeschi
Keyword(s):  
Heat Stress ◽  
Dry Matter ◽  
Management Practices ◽  
Animal Health ◽  
Bos Indicus ◽  
Physiological Adaptation ◽  
Feeding Strategies ◽  
Net Energy ◽  
Feed Composition ◽  
Diet Formulation

Abstract Contemporary nutritional research investigates the effects of diet formulation and feeding strategies on animal performance and global sustainability under different climates. Functional nutrition models have incorporated the effects of heat stress on net energy for maintenance requirements, dry matter intake (DMI), and milk production when accounting for animal and the environmental factors. It is commonly assumed that growing Bos indicus breeds receiving feedlot-type diets in tropical and subtropical regions have exhibited lower maintenance energy requirements than Bos taurus breeds. However, the ability to predict supplies of energy, protein, and minerals available to meet animal requirements depends on the accuracy and consistency of feed composition values obtained through digestibility trials and chemical analyses. Empirical observations indicate that feedstuffs grown in high temperatures affect cell wall lignification and metabolic activity rates, requiring special procedures for digestion trials. Similarly, physiological adaptation mechanisms in cattle in response to heat stress conditions include evapotranspiration, sweating, and drooling. Heat stress studies have reported a correlation between reduced DMI and increased dry matter digestibility for all breeds of cattle exposed to temperatures that exceed the upper critical temperatures. For that reason, diet formulation with integrated mathematical nutrition modeling can account for nutrient and animal variability, to improve total digestible nutrient values. Furthermore, the water requirement is influenced by stage and type of production, activity, diet composition, feed intake and environmental temperature. Adjustments in management practices could potentially result in reduced production losses caused by thermal heat stress. The utilization of region-specific facilities that accommodate cattle and ensure the availability and quality of drinking water will improve overall animal health and production. Cattle receiving high-concentrate diets in tropical and subtropical regions require adjustments in management and nutrition to mitigate challenges induced by heat stress environments, but improvements are warranted for required energy and water for Bos indicus breeds.

scholarly journals Accumulation of dry matter and nitrogen contents in banana 'Williams' (Musa AAA) plants in Uraba, Colombia

2014 ◽  
Vol 32 (3) ◽  
pp. 349-357 ◽  
Author(s):  
Jaime Torres B. ◽  
Jaiver Danilo Sánchez ◽  
Gerardo Cayón ◽  
Stanislav Magnitskiy ◽  
Aquiles Enrique Darghan
Keyword(s):  
Nitrogen Content ◽  
Dry Matter ◽  
Management Practices ◽  
Linear Models ◽  
Dry Weight ◽  
Production Cycle ◽  
Dry Matter Accumulation ◽  
Banana Production ◽  
Production Cycles ◽  
Selection Of

Banana production for export in the Uraba region of Colombia represents economic and social benefits for the country and demands improved agronomic management practices, especially for fertilization. The objective of this research was to evaluate the effect of different doses of nitrogen on crop development during two production cycles in order to adjust fertilizer recommendations to values consistent with plant requirements. Sixth-generation banana Williams plants were subjected to five treatments of nitrogen doses at five stages of development and during two production cycles. Two linear models, according to the phenological stage and vegetative structures, were used, assessing the variables of dry weight and nitrogen content. The statistical differences found for the effect of the nitrogen dose on the dry matter accumulation per plant organ and nitrogen content in the plants for the development stages per production cycle and between the cycles allowed for the selection of the 321.8 and 483 kg ha-1 ha of nitrogen doses as the better ones. In this research, the nitrogen dose of 483 kg ha-1 was the most successful at obtaining the highest nitrogen content in the plants. This research confirmed the practical utility of nutrient extraction curves because they allowed for the selection of the fertilizer dose with the best response.

Nitrate Leaching to a Shallow Mid-Atlantic Coastal Plain Aquifer as Influenced by Conventional No-Till and Low-Input Sustainable Grain Production Systems

1993 ◽  
Vol 28 (3-5) ◽  
pp. 691-700 ◽  
Author(s):  
J. P. Craig ◽  
R. R. Weil
Keyword(s):  
Management Practices ◽  
Production Systems ◽  
Cropping Systems ◽  
Cropping System ◽  
Atlantic Coastal Plain ◽  
Grain Production ◽  
Nitrogen And Phosphorus ◽  
Mineral N ◽  
Low Input ◽  
No Till

In December, 1987, the states in the Chesapeake Bay region, along with the federal government, signed an agreement which called for a 40% reduction in nitrogen and phosphorus loadings to the Bay by the year 2000. To accomplish this goal, major reductions in nutrient loadings associated with agricultural management practices were deemed necessary. The objective of this study was to determine if reducing fertilizer inputs to the NT system would result in a reduction in nitrogen contamination of groundwater. In this study, groundwater, soil, and percolate samples were collected from two cropping systems. The first system was a conventional no-till (NT) grain production system with a two-year rotation of corn/winter wheat/double crop soybean. The second system, denoted low-input sustainable agriculture (LISA), produced the same crops using a winter legume and relay-cropped soybeans into standing wheat to reduce nitrogen and herbicide inputs. Nitrate-nitrogen concentrations in groundwater were significantly lower under the LISA system. Over 80% of the NT groundwater samples had NO3-N concentrations greater than 10 mgl-1, compared to only 4% for the LISA cropping system. Significantly lower soil mineral N to a depth of 180 cm was also observed. The NT soil had nearly twice as much mineral N present in the 90-180 cm portion than the LISA cropping system.

Effect of Integrated Nutrient Management Practices on Growth and Development of Hybrid Maize Cultivar HQPM 1 in Mid-Hills of Meghalaya

2017 ◽  
Vol 4 (03) ◽  
Author(s):  
SAMBORLANG K. WANNIANG ◽  
A. K. SINGH
Keyword(s):  
Dry Matter ◽  
Management Practices ◽  
Nutrient Management ◽  
Dry Matter Accumulation ◽  
Integrated Nutrient Management ◽  
Graduate Studies ◽  
Green Manuring ◽  
Maize Cultivar ◽  
Significant Difference ◽  
Hybrid Maize

A field experiment was conducted during kharif 2011 on experimental farm of the College of Post Graduate Studies (CAU–Imphal), Umiam (Meghalaya) to evaluate the effect of integration of green manuring, FYM and fertilizers as integrated nutrient management (INM) practices on growth and developmental behaviour of quality protein maize cultivar QPM 1. The data revealed that comparatively higher amount of primary nutrients were added in green manured maize plots in comparison to non green manured treatments. Green manuring also left a positive response on plant height, CGR, RGR leaf area, and dry matter accumulation in plants though the difference between green manured and non-green manured treatments was at par. Treatments 75 % RDF + 5 t FYM ha-1, 50 % RDF + 7.5 t FYM ha-1, 100 % RDF ha-1 and 75 % RDF + 2.5 t FYM ha-1 recorded significantly higher values of all the above said growth parameters over 50 % RDF + 5 t FYM ha-1 and control treatments. At all stages of observations, the maximum dry matter was associated with RDF (recommended doses of fertilizers) which was at par with 75 % RDF + 5 t FYM ha-1, but significantly higher over the plant dry weight recorded from all remaining treatments. A Significant difference in CGR at 30 – 60 and 60 – 90 DAS stage and in RGR at 90 DAS - harvest stage was observed due to various combinations of recommended dose of fertilizer with different doses of FYM. Number of days taken to attain the stages of 50% tasselling, silking and maturity did not differ significantly due to green manuring. However, treatment 75 % RDF + 5 t FYM ha-1 took significantly lesser number of days for these stages than other treatment combinations. The superiority of the treatment 75 % RDF + 5 t FYM ha-1 indicated a possibility of substituting 25% of RDF with 5 t FYM ha-1 without any loss in dry matter accumulation in plants of the quality protein hybrid maize in mid-hill ecosystems of Meghalaya.

scholarly journals 395 Impact of pig mortality on U.S. pig producers

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 184-185
Author(s):  
Caleb M Shull
Keyword(s):  
Feed Efficiency ◽  
Management Practices ◽  
Production Systems ◽  
Research Priorities ◽  
Functional Approach ◽  
Production Cycle ◽  
Limiting Factor ◽  
Significant Challenge ◽  
The Relationship ◽  
Positive Step

Abstract Swine producers in the U.S. face a significant challenge. On top of the ever-changing market dynamics that lead to wide swings in profitability or loss, is an underlying issue of pig mortality that the industry must address. While significant improvements in total piglets born per litter have been achieved over the last 10 years, pig mortality has seen no improvement or has worsened (Figure 1). When expressed as a percentage of piglets born (excluding mummies), a total of 7.9% were recorded as stillborn and 13.4% died prior to weaning in 2019. Assuming a typical mortality range of 7–10% from weaning to harvest, a typical U.S. producer could expect to lose around 27–30% of all piglets born. In addition, the average producer had around 12% annual sow mortality (Figure 1). Litter size and post-weaning growth rate and feed efficiency will always factor heavily into research priorities due to the economic impact associated with those traits; however, the opportunity to drive value through reduction in pig losses across the production cycle is staggering. In defense of the industry, improving pig survival is not an easy task for a number of reasons. The sample size (i.e., number of pigs) required to do mortality research correctly is often a limiting factor for many production systems. Furthermore, a cross-functional approach is likely required to make significant improvements in mortality. Specifically, the relationship between genetics, health, and management practices warrant consideration. Recent collaboration across the industry to improve mortality is a positive step forward and this collaboration should continue moving forward.

scholarly journals Soil Health and Related Ecosystem Services in Organic Agriculture

2015 ◽  
Vol 4 (3) ◽  
pp. 116 ◽  
Author(s):  
Lynette K. Abbott ◽  
David A. C. Manning
Keyword(s):  
Management Practices ◽  
Nutrient Management ◽  
Soil Health ◽  
Microbial Transformation ◽  
Nutrient Release ◽  
Farming Systems ◽  
Organic Soil ◽  
Detailed Examination ◽  
Chemical Processes ◽  
Nitrogen And Phosphorus

<p>Soil health is dependent upon complex bio-physical and bio-chemical processes which interact in space and time. Microrganisms and fauna in soil comprise highly diverse and dynamic communities that contribute, over either short or long time frames, to the transformation of geological minerals and release of essential nutrients for plant growth. Certified organic soil management practices generally restrict the use of chemically-processed highly soluble plant nutrients, leading to dependence on nutrient sources that require microbial transformation of poorly soluble geological minerals. Consequently, slow release of nutrients controls their rate of uptake by plants and associated plant physiological processes. Microbial and faunal interactions influence soil structure at various scales, within and between crystalline mineral grains, creating complex soil pore networks that further influence soil function, including the nutrient release and uptake by roots. The incorporation of organic matter into soil, as either manure or compost in organic farming systems is controlled to avoid excessive release of soluble nutrients such as nitrogen and phosphorus, while simultaneously contributing an essential source of carbon for growth and activity of soil organisms. The interdependence of many soil physical and chemical processes contributing to soil health is strongly linked to activities of the organisms living in soil as well as to root structure and function. Capitalizing on these contributions to soil health cannot be achieved without holistic, multiscale approaches to nutrient management, an understanding of interactions between carbon pools, mineral complexes and soil mineralogy, and detailed examination of farm nutrient budgets.</p>

Determination of Nitrogen and Phosphorus Partitioning within Components of the Biomass in a High Rate Algal Pond: Significance for the Coastal Environment of the Treated Effluent Discharge

1992 ◽  
Vol 25 (12) ◽  
pp. 207-214 ◽  
Author(s):  
N. J. Cromar ◽  
N. J. Martin ◽  
N. Christofi ◽  
P. A. Read ◽  
H. J. Fallowfield
Keyword(s):  
Dry Matter ◽  
Coastal Environment ◽  
High Rate ◽  
Nutrient Input ◽  
Nitrogen And Phosphorus ◽  
Loading Rates ◽  
Effective Strategies ◽  
Treated Effluent ◽  
Algae And Bacteria

Two High-Rate Algal Ponds were operated over residence times of 4 and 6 days respectively, at three COD loading rates equivalent to 600, 350 and 100 kg ha−1d−1 from early September to late October 1991. Samples of pond N and P feed were analysed to obtain nutrient input values to the system. Pond filtrates were also analysed for soluble nutrients. The pond biomass was separated into constituent components of algae and bacteria. Following separation, the discrete fractions were analysed for dry matter, chlorophyll content, and paniculate carbon, hydrogen, nitrogen and phosphorus. Nitrogen and phosphorus balances were then calculated which were used to partition the nutrients into soluble and paniculate phases, and to further separate the paniculate phase into algal and bacterial components. The partitioning of these nutrients, responsible for eutrophication, enables the calculation of removal rates of N and P from the pond systems and makes possible more effective strategies for the removal of the nutrient-rich biomass from receiving water bodies.

Nitrogen, Phosphorus and Water Contents During Grain Development and Maturation in Wheat

1977 ◽  
Vol 4 (5) ◽  
pp. 799 ◽  
Author(s):  
I Sofield ◽  
IF Wardlaw ◽  
LT Evans ◽  
SY Zee
Keyword(s):  
Grain Growth ◽  
Dry Matter ◽  
Nitrogen Concentration ◽  
Growth Period ◽  
Calcium Content ◽  
Dry Weight ◽  
Water Entry ◽  
Grain Development ◽  
Nitrogen And Phosphorus ◽  
Steady Rate

Plants of five cultivars of wheat were grown under controlled-environmental conditions in order to analyse the effect of cultivar and of temperature and illuminance after anthesis on the accumulation of nitrogen and phosphorus by grains in relation to dry matter. The water relations of the grain during maturation were also examined, using calcium content as an index of water entry. The nitrogen and phosphorus contents of grains increased linearly throughout the grain growth period. The percentage of nitrogen and phosphorus in grains fell sharply during the first few days after anthesis but rose progressively thereafter. The higher the temperature, and the lower the illuminance, the higher was the percentage of nitrogen in the grain of all cultivars. Such conditions also reduce final grain size, but their effects on nitrogen concentration in the grain were apparent early in grain development. No evidence was found of a flush of nitrogen or phosphorus into the grain late in its development. Water entry into the grain continued at a steady rate until maximum grain dry weight was reached, then ceased suddenly. No evidence was found of an increased rate of water loss by the grain at that stage, and the rapid fall in water content at the cessation of grain growth may have been due to blockage of the chalazal zone of entry into the grain by the deposition of lipids. Accumulation of dry matter, nitrogen and phosphorus and entry of water into the grain all ceased at the time of lipid deposition in the chalazal zone.

Sign in / Sign up

Export Citation Format

Share Document