scholarly journals Tilapia rendalli increases phytoplankton biomass of a shallow tropical lake

2014 ◽  
Vol 26 (4) ◽  
pp. 429-441 ◽  
Author(s):  
Lúcia Helena Sampaio da Silva ◽  
Marlene Sofia Arcifa ◽  
Gian Salazar-Torres ◽  
Vera Lúcia de Moraes Huszar
Keyword(s):  
Treatment Group ◽  
Phytoplankton Biomass ◽  
Experimental Period ◽  
Control Group ◽  
Filter Feeding ◽  
Tropical Reservoir ◽  
Tropical Water ◽  
Tilapia Rendalli ◽  
Physical And Chemical Variables ◽  
Physical And Chemical

AIM: This study aimed to experimentally test the influence of a planktivorous filter-feeding fish (Tilapia rendalli) on the phytoplankton dynamics of a small and shallow tropical reservoir (Lake Monte Alegre, Brazil). Adults of T. rendalli of this lake feed preferentially on phytoplankton, and we hypothesize that: I) adults of T. rendalli will decrease the phytoplankton biomass and composition through direct herbivory, and II) as it is a eutrophic system, fish would not have strong influence on phytoplankton through nutrient cycling. METHODS: To evaluate these different effects on algae, a field experiment was performed in the summer period for 15 days, in mesocosms isolated from the sediment, using a control group (no fish) and a treatment group (with one fish in each mesocosm). Physical and chemical variables and phyto- and zooplankton were evaluated at the start, middle, and end of the experiment. RESULTS: At the end of the experiment, it was observed a significant increase in ammonium concentrations and total phytoplankton biomass, Cyanobacteria and Zygnemaphyceae and all size classes except class II (20-30 µm) in the treatment group (with fish). The biomass increase of the potentially toxic cyanobacterium Cylindrospermospsis raciborskii was also observed in the fish treatment at the end of the experimental period. CONCLUSION: This study did not support both initial hypotheses. It supports the assertion that in tropical water bodies, with similar characteristics to the environment studied, planktivorous filter-feeding fish, such as T. rendalli, are not effective in reducing phytoplankton biomass through direct grazing, even when phytoplankton is one of their main food items. T. rendalli can contribute to the increase of phytoplankton biomass and can promote or increase the eutrophication of aquatic systems.

Effect of Chelated Mineral Mixture on Blood Biochemistry, Hormone and Mineral Status in Repeat Breeder Buffaloes in Tribal Areas of Dahod District in Gujarat, India

2019 ◽  
Vol 15 (01) ◽  
pp. 40-44 ◽  
Author(s):  
P M Joshi ◽  
D Patel ◽  
P D Patel
Keyword(s):  
Treatment Group ◽  
Experimental Period ◽  
Serum Glucose ◽  
Blood Biochemistry ◽  
Control Group ◽  
Blood Collection ◽  
Mineral Status ◽  
Blood Biochemical ◽  
Mineral Mixture ◽  
Repeat Breeder

An on-farm trial for 90 days was conducted at four tribal villages to assess the effect of chelated mineral mixture (CMM) supplementation on blood biochemistry as well as hormonal and mineral status, nutrient intake and reproductive performance of the repeat breeder buffaloes (n = 24). The animals selected were randomly divided into two groups of 12 animals each. The group T1 was control group (farmer’s feeding schedule), and T2 treatment group (T1 + CMM @ 50 g/animal/day). Blood collection was done at 0, 45 and 90 days of the experiment from both the groups for assessment of blood biochemical, hormonal and mineral status of the animals. Average DM, DCP and TDN intake in repeat breeder buffaloes calculated as per information collected from farmers were statistically similar among both the groups and were as per ICAR requirements of animals. Results revealed significant (p less than 0.05) improvement in hemoglobin, serum glucose, total protein, total cholesterol, progesterone, and macro (Ca, P)–micro (Zn, Fe, Cu, Co, Mn) mineral status of chelated mineral supplemented group as compared to control animals. The number of days taken for a successful conception in repeat breeder buffaloes as well as the cost of feeding was also reduced upon supplementation of CMM in T2 as compared to T1 group. The control group recorded a 22.12% higher cost of rearing than the treatment group during the experimental period. The findings revealed the beneficial role of cheated minerals supplementation in improving health, nutritional and reproductive status of repeat breeding buffaloes.

scholarly journals Study on effect of different levels of concentrate on growth performance of both male and female lamb

2016 ◽  
Vol 2 (2) ◽  
pp. 274-278
Author(s):  
Masum Billah ◽  
Md Humayun Kabir ◽  
Md Hafizur Rahman ◽  
Md Abdul Hamid
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Treatment Group ◽  
Live Weight ◽  
Experimental Period ◽  
Control Group ◽  
Male And Female ◽  
Live Weight Gain ◽  
Concentrate Supplementation ◽  
Concentrate Mixture

The present study was carried out to assess the effect of concentrate on growth performances of both male and female lamb. For this purpose twenty four (12 male and 12 female) lamb aged about 5-6 months were selected and divided into three groups (Treatment group T1, T2 and control group T0). In each group having 4 males and 4 females lamb, all lambs were supplied green roughages ad-libitum, control group T0 was allowed no concentrate and treatment group T1 & T2 were supplied 100 gm & 200 gm concentrate mixture respectively for 90 days experimental period. Animals were weighed at 15 days interval. Significant differences of live weight gain among these three groups were found. Allowing 100 gm (T1) concentrate mixture along with green grass improved growth rate in both male and female lamb. Increasing of concentrate supplementation improved live weight gain (found in T2 group). Total live weight gain (kg) and average daily live weight gain (g/d) were 4.25±0.52 kg and 47.20±5.75 g, 5.38±0.83 kg and 59.73+9.17 g and 7.00±0.54 kg and 77.78±6.00 g in male lambs and 2.25±0.21 kg and 25.00±2.34 g, 3.18±0.32 kg and 35.39±3.63 g and 3.81±0.24 kg and 42.33±2.77 g in female lambs for the To, T1 and T2 groups respectively. Live weight was significantly (P<0.05) higher in male than female lambs. The results showed that 100 g concentrate supplementation with green roughages improved growth rate in lambs (male and female) under stall feeding condition. Increase of supplementation might improve nutrients supply to promote higher live weight gain.Asian J. Med. Biol. Res. June 2016, 2(2): 274-278

Water level decrease and increased water stability promotes phytoplankton growth in a mesotrophic subtropical lake

2015 ◽  
Vol 66 (8) ◽  
pp. 711 ◽  
Author(s):  
Eduardo V. Fuentes ◽  
Mauricio M. Petrucio
Keyword(s):  
Water Level ◽  
Phytoplankton Biomass ◽  
Algal Blooms ◽  
Freshwater Ecosystems ◽  
Rainfall Regime ◽  
Water Stability ◽  
Strong Reduction ◽  
Influence Of Water ◽  
Physical And Chemical Variables ◽  
Physical And Chemical

Global warming and climate variability can promote changes in freshwater ecosystems that may result in increased frequency of algal blooms. These effects, however, depend strongly on local factors. Peri Lake is a cyanobacteria-dominated shallow lake that has experienced a strong reduction in water level, as well as increased occurrence of algal blooms. The goal of this study was to determine the influence of water level on phytoplankton biomass in Peri Lake. We hypothesise that increased algal blooms are associated with reduction in water level, possibly in response to changes in rainfall patterns. We measured meteorological, physical, and chemical variables over 5 years, as well as chlorophyll-a levels. We observed a strong reduction in total rainfall in the last year of the study, in which the flow of lake water nearly ceased. Phytoplankton biomass increased despite a lack of evidence of water heating or eutrophication. Our results suggest that changes in rainfall regime alter lake characteristics such as retention time and water stability (i.e. increased occurrence of diurnal stratification events), producing favourable conditions for growth of cyanobacterial biomass. These effects perhaps better explain increases in algal biomass in this system than do temperature or nutrient availability alone.

scholarly journals Effect of environmental enrichment for piglets in the nursery phase

2021 ◽  
Vol 34 (1) ◽  
pp. 154-160
Author(s):  
Joselaine Bortolanza Padilha-Boaretto ◽  
Priscila Michelin Groff-Urayama ◽  
Suelen Maria Einsfeld ◽  
Cleverson de Souza ◽  
Angélica Signor Mendes ◽  
...  
Keyword(s):  
Treatment Group ◽  
Environmental Enrichment ◽  
Experimental Period ◽  
Video Camera ◽  
Control Treatment ◽  
Control Group ◽  
Treatment Groups ◽  
Bonferroni Test ◽  
Parametric Analyses ◽  
Control Treatment Group

Objective: The effect of environmental enrichment on the behaviour of piglets in the nursery phase was evaluated.Methods: A total of 450 hybrid pigs (21 day old), including both females and uncastrated males, weighing approximately 6 kg, were distributed in a completely randomised design with 3 treatments and 3 replicates of 50 animals each. The treatments were: i) pen without environmental enrichment (control), ii) treatment consisting of continuous environmental enrichment (CEE) with rubber balls throughout the experimental period, and iii) treatment consisting of environmental enrichment with washed balls (EEWB) during the whole experimental period which were removed daily for washing. For the behavioural evaluation, 10 animals were randomly selected per replicate. The behavioural assessments were performed once a week, from 8 am to 6 pm, using images captured with a video camera. The data were submitted to non-parametric analyses, the means were compared using the Bonferroni test, and Person’s correlations were also calculated.Results: A statistical difference (p = 0.001) was observed in the B5 (playful) behaviour; the animals in the EEWB treatment group had a higher frequency of this behaviour than animals in the control treatment group. The animals in the control group showed a higher frequency of B7 behaviour (lying down) (p = 0.026) than those in the EEWB and CEE treatment groups. The animals in the control group had a higher frequency of the B9 (belly nosing) behaviour than those in the EEWB group (p = 0.015). There was a tendency towards a higher frequency of behaviour B3 (walking in the pen) (p = 0.067) when the animals received the control treatment than treatments EEWB or CEE.Conclusion: The use of an enriching object improved the animal welfare and altered the correlation between the evaluated behaviours compared to the animals that did not have environmental enrichment.

scholarly journals Invasion of the dinoflagellate Ceratium furcoides (Levander) Langhans 1925 at tropical reservoir and its relation to environmental variables

2012 ◽  
Vol 12 (2) ◽  
pp. 93-100 ◽  
Author(s):  
Lidiane Cristina da Silva ◽  
Isabela Carnielli Leone ◽  
Maria José dos Santos-Wisniewski ◽  
Alberto Carvalho Peret ◽  
Odete Rocha
Keyword(s):  
Environmental Variables ◽  
Rio Grande ◽  
Domestic Sewage ◽  
Tropical Reservoir ◽  
Reservoir Water ◽  
Rio Grande Basin ◽  
Physical And Chemical Variables ◽  
Nitrate And Nitrite ◽  
Physical And Chemical ◽  
Plankton Communities

Dinoflagellates of the genus Ceratium are chiefly marine but there are rare occurrences in freshwater. In this study we analyze the invasion and progressive establishment of Ceratium furcoides, an exotic species, in the Furnas Reservoir. Samples were taken at 36 points in the reservoir, during the months of March, June, September and December, 2007. Measurements of some physical and chemical variables were simultaneously performed at each site. The occurrence of C. furcoides was registered at 20 sites, with densities varying between 0.57 and 28,564,913.0 ind.m-3. Blooms of this species were recorded in points which were classified as mesotrophic, coinciding with the places receiving high amounts of untreated domestic sewage. C. furcoides density was correlated with temperature, nutrients (nitrate and nitrite) and water electric conductivity. The highest density was recorded in June when temperature was low. The presence of Ceratium furcoides in the reservoir apparently has not yet affected the reservoir water quality or other plankton communities. However, if it becomes fully established it could perhaps become a problem in the reservoir or even to spread out to other reservoirs in Rio Grande basin.

scholarly journals The first floristic study of freshwater dinoflagellates (Dinophyceae) in Colombia

2021 ◽  
Author(s):  
Carolina Bustamante-Gil ◽  
Eduardo Amat ◽  
Andrés Boltovskoy ◽  
John J. Ramírez-Restrepo
Keyword(s):  
Environmental Variables ◽  
Water Systems ◽  
Water Bodies ◽  
Tropical Water ◽  
Floristic Study ◽  
Ecological Aspects ◽  
Apparent Color ◽  
Physical And Chemical Variables ◽  
Physical And Chemical ◽  
Comprehensive Study

The first comprehensive study of dinoflagellate flora and their related environmental variables in reservoirs, swamps, and an insular lake of Colombia is presented. Fourteen Colombian water bodies were assessed. In each, water temperature, electric conductivity, oxygen saturation, turbidity, and apparent color were the physical and chemical variables measured. Twelve dinoflagellate taxa were recorded, indicating a considerable richness compared to similar surveys. Ensembles recovered showed a spatial structuration mediated by the type of the water bodies (reservoirs and swamps); environmental variables and species richness explained equally the differences among the water bodies. The dinoflagellate flora showed altitudinal segregation, with intermediate altitude systems displaying the highest richness values. A brief discussion about the geographical distribution of the species collected is offered. The study contributes to the knowledge of the ecological aspects of dinoflagellate flora and outlines preliminary biodiversity tendencies of ensembles in tropical water systems.

scholarly journals Environmental factors driving phytoplankton biomass and diversity in a tropical reservoir

2020 ◽  
Vol 44 (171) ◽  
pp. 423-436
Author(s):  
Isabel Cristina Gil Guarín ◽  
Silvia Lucía Villabona-González ◽  
Edison Parra-García ◽  
Ricardo O. Echenique
Keyword(s):  
Transition Zone ◽  
Phytoplankton Biomass ◽  
Vertical Gradient ◽  
Temporal Variations ◽  
Water Levels ◽  
Ex Situ ◽  
Spatial And Temporal Variation ◽  
Tropical Reservoir ◽  
Vertical Scale ◽  
Physical And Chemical Variables

We determined the spatial and temporal variation of phytoplankton biomass and diversity in 10 fortnightly sampling journeys verifying five sampling sites in El Peñol-Guatapé reservoir located in Antioquia, Colombia. In situ and ex situ physical and chemical variables were measured and phytoplankton samples were taken. Richness was dominated by Chlorophyta and biomass by Dinophyta. This variable was higher in the transition zone while in the riverine zone it showed average values, the lowest were registered in the lacustrine zone. Diversity was lower in the riverine zone, but it increased considerably in the transition zone and in the lacustrine zone where it showed similar values. At the vertical scale, biomass and diversity did not vary widely. Biomass showed a differential response to the effect of precipitation changes and water  levels in the reservoir zones. Due to the low variability in environmental conditions, diversity was homogeneous time-wise. These results suggest that factors related to the hydrodynamic such as precipitation and water level resulting from the dam operation and inflow have a slight influence on the temporal variations of phytoplankton biomass and structure. There was a direct relationship between these attributes and physical variables such as turbidity and nutrients concentration at spatial scale while at the vertical scale, mixing patterns and the influence of the wind explained the absence of the vertical gradient of biomass and phytoplankton structure.

scholarly journals Effect of magnetized water on morphologically abnormal sperms and histopathological status of testis in mice

2012 ◽  
Vol 6 (2) ◽  
pp. 28-35
Author(s):  
Gulboy A. Nasir
Keyword(s):  
Treatment Group ◽  
Tap Water ◽  
Experimental Period ◽  
Seminiferous Tubules ◽  
Control Group ◽  
Magnetized Water ◽  
Spherical Head ◽  
Hammer Head ◽  
Group 2 ◽  
Testis Tissue

ifty white Swiss male mice (6-7) weeks of age were randomly divided into two groups, and each group included 25 mice. Group 1 (treatment group) were get magnetic water, group 2 (control group) were get tap water. After whole experimental period (16 weeks), Animals sacrificed and sperms were collected from epididimyes, then histopathology for testis tissue was done and morphologically abnormal sperm of head sperm percentage were calculated. Results revealed that abnormalities of head sperm percentage in treatment group 0.99% were reduced compared with control group 1.03%, but the differences were not significant. Means of narrow head, loss hook head, hammer head and bacillary head in control group were insignificantly (P>0.05) more than treatment group, but mean of spherical head in treatment group 1.63 was mathematically higher than its similar in control group 1.44, simple correlation coefficient between all kinds of abnormalities was insignificant except that between loss hook head and hammer head (-0.27) which exhibited significant differences (p<0.05). No significant reduction was observed in motality percentage of sperms, dead and abnormalities of sperms in the treatment group compared to control group. Significant increase (P<0.01) was observed in seminiferous tubules diameters in the treatment group, whereas primary spermatocytes, spermatids and interstitial spaces exhibited insignificant increase in treatment group compared with control group.

scholarly journals Effect of Chelated Mineral Mixture on Blood Profile and Fertility in Anoestrus Buffaloes of Tribal Areas of Dahod District in Gujarat, India

2020 ◽  
Vol 15 (03) ◽  
pp. 61-65
Author(s):  
DC Patel ◽  
PM Joshi ◽  
PD Patel ◽  
NP Sarvaiya
Keyword(s):  
Treatment Group ◽  
Experimental Period ◽  
Serum Glucose ◽  
Control Group ◽  
Blood Collection ◽  
Blood Profile ◽  
Mineral Status ◽  
Blood Biochemical ◽  
Mineral Mixture ◽  
To Come

An on-farm trial for 90 days was conducted at four tribal villages to assess the effect of chelated mineral mixture (CMM) supplementation on blood biochemistry as well as hormonal and mineral status, nutrient intake and reproductive performance of the anoestrus buffaloes (n=24). The animals selected were randomly divided into two groups of 12 animals each. The group T1 was the control group (farmer’s feeding schedule), and T2 treatment group (T1 + CMM @ 50 g/animal/day). Blood collection was done on days 0, 45, and 90 of the experiment from the animals of both the groups for assessment of blood biochemical, hormonal, and mineral status of the animals. Average DM, DCP, and TDN intake in anoestrus buffaloes calculated as per information collected from farmers were statistically similar among both the groups and were as per ICAR requirements of animals. Results revealed significant (p less than 0.05) improvement in hemoglobin, serum glucose, total protein, total cholesterol, progesterone, estradiol and macro (Ca, P) – micro (Zn, Fe, Cu, Co, Mn) mineral status of chelated mineral supplemented group as compared to control animals. The number of days taken to come into oestrus in anoestrus buffaloes (51.22±3.78 vs 75.00±6.18 days for 9 vs 5 animals), as well as the cost of feeding (Rs. 5441 vs 8039), was also significantly (pless than 0.05) reduced upon supplementation of CMM as compared to control group. The control group recorded a 32.32% higher cost of rearing than the treatment group during the experimental period. The findings revealed the beneficial role of chelated minerals supplementation in improving the health, nutritional and reproductive status of anoestrus buffaloes.

A Newspaper’s Effect on the Strength of Automatic Associations in Memory

2012 ◽  
Vol 24 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Florian Arendt
Keyword(s):  
Treatment Group ◽  
Term Effect ◽  
Control Group ◽  
Implicit Measure ◽  
Short Term ◽  
Short Term Treatment ◽  
Short Term Effect ◽  
Automatic Associations ◽  
Foreign Nationality ◽  
The Impact

A test was done to see if reading a newspaper which consistently overrepresents foreigners as criminals strengthens the automatic association between foreign country and criminal in memory (i.e., implicit cultivation). Further, an investigation was done to find out if reading articles from the same newspaper produces a short-term effect on the same measure and if (1) emotionalization of the newspaper texts, (2) emotional reactions of the reader (indicated by arousal), and (3) attributed text credibility moderate the short-term treatment effect. Eighty-five participants were assigned to one of three experimental conditions. Participants in the control group received short factual crime texts, where the nationality of the offender was not mentioned. Participants in the factual treatment group received the same texts, but the foreign nationality was mentioned. Participants in the emotionalized treatment group received emotionalized articles (i.e., texts which are high in vividness and frequency) covering the same crimes, with the foreign nationality mentioned. Supporting empirical evidence for implicit cultivation and a short-term effect was found. However, only emotionalized articles produced a short-term effect on the strength of the automatic association, indicating that newspaper texts must have a minimum of stimulus intensity to overcome an effect threshold. There were no moderating effects of arousal or credibility pertaining to the impact on the implicit measure. However, credibility moderated the short-term effect on a first-order judgment (i.e., estimated frequency of foreigners of all criminals). This indicates that a newspaper’s effect on the strength of automatic associations is relatively independent from processes of propositional reasoning.

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