scholarly journals Forage productivity and chemical composition of Megathyrsus maximus cv. Tamani under defoliations regimes

PubVet ◽  
2021 ◽  
Vol 15 (10) ◽  
pp. 1-7
Author(s):  
Newton de Lucena Costa ◽  
Liana Jank ◽  
João Avelar Magalhães ◽  
Antônio Neri Azevedo Rodrigues ◽  
Amaury Burlamaqui Bendahan ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Dry Matter ◽  
Canopy Structure ◽  
Field Conditions ◽  
Tissue Concentrations ◽  
Natural Field ◽  
Defoliation Frequency ◽  
Forage Utilization

The effects of defoliation frequency (21, 28, 35 and 42 days) and defoliation intensity (20, 30 and 40 cm above the ground) on green dry matter (GDM) yield, and chemical composition of Megathyrsus maximus cv. Tamani were evaluated under natural field conditions at the Roraima´s savannas. Defoliation regimes affect productivity and chemical composition of M. maximus cv. Tamani forage. The decrease in the pasture defoliation frequency and intensity improved the accumulation of forage, however it reduces the tissue concentrations of N, P, Ca, Mg and K. Irrespective of defoliation frequencies, the highest levels of N (25.31 g kg-1), P (2.11 g kg-1), Mg (2.78 g kg-1) and K (21.13 g kg-1) were recorded for the defoliation intensity at 40 cm above the ground, except for Ca (4.31 g kg-1), where the greatest concentration was obtained with defoliations at 30 cm above the ground. The use of defoliation frequency around 32 days and defoliation intensity of 28 cm above the ground can be considered adequate for the management of pastures of M. maximus cv. Tamani, in order to provides higher forage productivity and quality, regrowth vigor, larger efficiency of forage utilization, greater tissue renewal and canopy structure more favorable to grazing.

scholarly journals Forage productivity and chemical composition of Panicum maximum cv. Mombaça under defoliations intensities and frequencies

2021 ◽  
Vol 10 (8) ◽  
pp. e42910817494
Author(s):  
Newton de Lucena Costa ◽  
Liana Jank ◽  
João Avelar Magalhães ◽  
Amaury Burlamaqui Bendahan ◽  
Braz Henrique Nunes Rodrigues ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Dry Matter ◽  
Canopy Structure ◽  
Field Conditions ◽  
Panicum Maximum ◽  
Tissue Concentrations ◽  
Natural Field ◽  
Defoliation Frequency ◽  
Forage Utilization

The effects of defoliation frequency (28, 35, 42 and 49 days) and defoliation intensity (30, 40 and 50 cm above the ground) on green dry matter (GDM) yield, and chemical composition of Panicum maximum cv. Mombaça were evaluated under natural field conditions at the Roraima´s savannas. Defoliation regimes affect productivity and chemical composition of grass forage. The decrease in the pasture defoliation frequency and intensity improved the accumulation of forage, however it reduces the tissue concentrations of N, P, Ca, Mg and K. Irrespective of defoliation frequencies, the highest levels of N (23.99 g kg-1), P (2.12 g kg-1), Ca (4.22 g kg-1), Mg (2.87 g kg-1) and K (21.45 g kg-1) were recorded for the defoliation intensity at 40 cm above the ground. The use of defoliation frequency around 42 days and defoliation intensity of 42,9 cm above the ground can be considered adequate for the management of pastures of P. maximum cv. Mombaça, in order to provides higher forage productivity and quality, regrowth vigor, larger efficiency of forage utilization, greater tissue renewal and canopy structure more favorable to grazing.

scholarly journals Validation of loop-mediated isothermal amplification for the detection of Loa loa infection in Chrysops spp in experimental and natural field conditions

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Glory Ngongeh Amambo ◽  
Raphael Awah Abong ◽  
Fanny Fri Fombad ◽  
Abdel Jelil Njouendou ◽  
Franck Nietcho ◽  
...  
Keyword(s):  
Lamp Assay ◽  
Isothermal Amplification ◽  
Field Conditions ◽  
Infection Rates ◽  
Loa Loa ◽  
Significant Drop ◽  
Natural Field ◽  
North West ◽  
Loop Mediated Isothermal Amplification ◽  
The North

Abstract Background The mass drug administration of ivermectin for onchocerciasis control has contributed to a significant drop in Loa loa microfilaria loads in humans that has, in turn, led to reduction of infection levels in Chrysops vectors. Accurate parasite detection is essential for assessing loiasis transmission as it provides a potential alternative or indirect strategy for addressing the problem of co-endemic loiasis and lymphatic filariasis through the Onchocerciasis Elimination Programme and it further reflects the true magnitude of the loiasis problem as excess human mortality has been reported to be associated with the disease. Although microscopy is the gold standard for detecting the infection, the sensitivity of this method is compromised when the intensity of infection is low. The loop-mediated isothermal amplification (LAMP) assay of parasite DNA is an alternative method for detecting infection which offers operational simplicity, rapidity and versatility of visual readout options. The aim of this study was to validate the Loa loa LAMP assay for the detection of infected Chrysops spp. under experimental and natural field conditions. Methods Two sets of 18 flies were fed on volunteers with either a low (< 10 mf/ml) or high (> 30,000mf/ml) microfilarial load. The fed flies were maintained under laboratory conditions for 14 days and then analysed using LAMP for the detection of L. loa infection. In addition, a total of 9270 flies were collected from the north-west, east, and south-west regions (SW 1 and 2) of Cameroon using sweep nets and subjected to microscopy (7841 flies) and LAMP (1291 flies plus 138 nulliparous flies) analyses. Results The LAMP assay successfully detected parasites in Chrysops fed on volunteers with both low and high microfilariaemic loads. Field validation and surveillance studies revealed LAMP-based infection rates ranging from 0.5 to 31.6%, with the lowest levels in SW 2 and the highest infection rates in SW 1. The LAMP assay detected significantly higher infection rates than microscopy in four of the five study sites. Conclusion This study demonstrated the potential of LAMP as a simple surveillance tool. It was found to be more sensitive than microscopy for the detection of experimental and natural L. loa infections in Chrysops vectors.

scholarly journals Some factors influencing the chemical composition of mixed rumen bacteria

1974 ◽  
Vol 31 (1) ◽  
pp. 27-34 ◽  
Author(s):  
R. H. Smith ◽  
A. B. Mcallan
Keyword(s):  
Chemical Composition ◽  
Dry Matter ◽  
Rumen Bacteria ◽  
Host Animal ◽  
Adult Cattle ◽  
Total N ◽  
Adult Sheep ◽  
Factors Influencing ◽  
Mixed Bacteria ◽  
Ciliate Protozoa

1. Sheep, cows and calves fitted with rumen cannulas were given diets mostly containing 10–16 g nitrogen/kg dry matter and consisting of roughage and cereals. Mixed bacteria were separated from samples of their rumen contents.2. Bacteria taken 4–6 h after a feed from calves which were kept in an experimental calf-house with no contact with adult animals (environment A) contained more α-dextran, less total N and higher nucleic acid:total N ratios than similar bacteria from calves reared in contact with adult sheep (environment C) but otherwise treated in an identical way.3. Mixed bacteria taken 4–6 h after a feed from sheep and cows were similar in composition, with respect to nitrogenous components, to those from the ‘environment C’ calves. This composition did not vary significantly when diets containing differing proportions of roughage were given.4. The ‘environment A’ calves were free of ciliate protozoa. When they were placed in contact with, and were inoculated with rumen contents from, adult cattle (environment B), they rapidly developed a normal protozoal population and the chemical composition of their rumen bacteria became like that of the bacteria from the ‘environment C’ calves.5. Mixed bacteria taken just before a feed, from either cows or ‘environment A’ calves, showed significantly lower RNA-N:total N ratios and slightly (but not usually significantly) higher DNA-N:total N ratios than bacteria taken 4–6 h after feeding. Total N contents of the bacteria did not change consistently with time after feeding.6. The possible significance of these differences in relation to the nutrition of the host animal is discussed.

Effect of harvesting stage on cereal and legume forage production in low rainfall regions

1976 ◽  
Vol 86 (1) ◽  
pp. 155-161 ◽  
Author(s):  
A. Hadjichristodoulou
Keyword(s):  
Chemical Composition ◽  
Protein Content ◽  
Dry Matter ◽  
Moisture Stress ◽  
N Fertilization ◽  
Forage Production ◽  
Common Vetch ◽  
Three Stages ◽  
Harvesting Stage ◽  
Percentage Protein

SUMMARYThe effect of stage of harvesting on dry-matter (D.M.) yield and chemical composition of barley, wheat and the legumes common vetch (F. sativa), woollypod vetch (F. dasycarpa) and fodder peas (P. sativum) were studied in Cyprus under low rainfall conditions in a series of trials sown in four successive years. Cereals were harvested at the beginning of heading, 50% heading and the milk stage of grain, and legumes at three stages from preflowering to full pod formation, D.M., protein and digestible D.M. yields and percentage D.M. content increased with age, whereas percentage protein content and D.M. digestibility declined. Under moisture stress conditions before and during the harvesting period D.M. yields did not increase significantly with age. Protein content of cereals under low rainfall conditions was higher than that of cereals grown in the U.K. under higher N fertilization levels. Rainfall conditions affected drastically the performance of both cereals and legumes. However, average yields were satisfactory; the barley variety 628 gave 8·98 t/ha, the highest D.M. yield among all cereal and legume varieties.

scholarly journals The effect of differing types of cloth and of contamination by non-feed nitrogen on intestinal digestion estimates using porous synthetic-fibre bags in a cow

1990 ◽  
Vol 63 (2) ◽  
pp. 221-229 ◽  
Author(s):  
Tuomo Varvikko ◽  
Aila Vanhatalo
Keyword(s):  
Free Surface ◽  
Chemical Composition ◽  
Pore Size ◽  
Surface Area ◽  
Dry Matter ◽  
Synthetic Fibre ◽  
Aqueous Suspension ◽  
Barley Straw ◽  
Intestinal Digestion ◽  
Free Surface Area

The influence of free surface area and pore size of a synthetic-fibre bag, and flow of intestinal substances into the bag, on the intestinal digestion estimates by the nylon-bag method of dry matter (DM), neutral detergent fibre (NDF), nitrogen, NDF-N and feed 15N was studied using a non-lactating cow fed on hay supplemented with barley and oats at maintenance level. The bags containing 15N-labelled ground ryegrass (Lolium perenne), barley, barley straw or rapeseed (Brassica napus) straw were introduced into the duodenum through a T-shaped cannula and collected from the faeces. Also, the disappearance of N from the bag was related to the true intestinal N digestion by comparing it with the net loss between duodenum and faeces of 15N in ryegrass introduced into the duodenum in an aqueous suspension. It was noted that the bag cloth often significantly affected both disappearance values and the subsequent chemical composition of the residues. Re-analysing part of the data as a 2x2 factorial (free surface x pore size) suggested that free surface area was often more important than pore size as a determinant of both disappearance values and chemical composition. Lower apparent (Kjeldahl N) than true (15N) feed N disappearance from the bag suggested a notable proportion of non-feed N in the residues, especially with fibrous feeds with low N. With ryegrass, 15N net loss within the intestine was lower than 15N disappearance from the bags. It was concluded that disappearance of Kjeldahl N is an underestimate of feed N disappearance from bags, but may possibly be an overestimate of the true intestinal digestion of feed N.

scholarly journals Effect of Planting Time on Canopy Structure and Biomass Production in Some Soybean Genotypes

1970 ◽  
pp. 25-29
Author(s):  
MK Uddin ◽  
MK Hasan ◽  
AKMA Alam
Keyword(s):  
Plant Height ◽  
Biomass Production ◽  
Dry Matter ◽  
Canopy Structure ◽  
Morphological Structure ◽  
Dry Weight ◽  
Shoot Biomass ◽  
Late Planting ◽  
Planting Time ◽  
Soybean Genotypes

A field experiment was conducted in the Field Laboratory of the Department of Crop Botany, BAU, Mymensingh during November 2003 to May 2004 to assess the effect of planting time (November and December) on some morphological structure, and root & shoot biomass production in four soybean genotypes (GPB-1, GPB-2, AGS-332 and AGS-11-35). The plant height, stem base diameter, seed dry weight plant-1 were significantly greater in the late planting crops (December) but number of branches plant-1, number of leaves plant-1, leaves dry weight plant-1, shoots dry weight plant-1, roots dry weight plant-1, total dry matter plant-1 were also significantly greater in November planting. Highest plant height, branches plant-1 and leaves plant-1, shoot dry weight plant-1 and total dry matter were found in GPB-2 genotype. Key words: Early and late planting, shoot and root mass, Glycine max. DOI = 10.3329/jard.v5i1.1453 J Agric Rural Dev 5(1&2), 25-29, June 2007

scholarly journals Estimation of ascochytosis infection of samples and lines of chickpea sorts in natural field conditions in Uzbekistan

2020 ◽  
pp. 74-77
Author(s):  
J. T. Nakhalbaev ◽  
I. Kh. Khamdamov
Keyword(s):  
Field Conditions ◽  
Seed Infection ◽  
Natural Field ◽  
The Third ◽  
Experimental Station ◽  
Leguminous Crops ◽  
Sowing Period ◽  
Research Institute

Relevance and methods. The information on the influence of samples of chickpea sorts, time of planting the lines of chickpeas on seed infection with ascochytosis and on the weight of grain on one plant bush is presented in this article. Samples of chickpea sorts and lines were studied during the first sowing period — the first decade of March and the second sowing period — the third decade of March. Ascochytosis infection was evaluated in natural field conditions. The study was conducted at the Central Experimental Station of the Galaaral Research Institute of Grain and Leguminous Crops in 2015–2017 in Uzbekistan.Results. According to the three-year study, it was found that in the years when there was a lot of precipitation days, sorts Yulduz, ILC 263 and MП 2015/1 of the lines during the first sowing were determined to be infected with acochytosis up to 6 points. During the first sowing period of this cv., there was a decrease in the weight of grains on one plant bush compared to the second sowing period. Cv. ILC 3279, Umid and line 14442 were found to be virtually undamaged in natural field conditions with ascohitosis during both planting periods. It wasfound our that the weight of cv. Мustaqillik-20, line 14442 grain on one plant bush remained high during both planting periods.

Sign in / Sign up

Export Citation Format

Share Document