scholarly journals A viewpoint on the use of microalgae as an alternative feedstuff in the context of pig and poultry feeding—a special emphasis on tropical regions

2021 ◽  
Vol 53 (3) ◽  
Author(s):  
Andreia A. M. Chaves ◽  
Cátia F. Martins ◽  
Daniela F. P. Carvalho ◽  
David M. Ribeiro ◽  
Madalena Lordelo ◽  
...  
2020 ◽  
Vol 79 (2) ◽  
pp. 129-141
Author(s):  
M. E. Sanyaolu ◽  
Oluropo F. Dairo ◽  
A. A. Willoughby ◽  
L. B. Kolawole

2008 ◽  
Vol 6 (2) ◽  
Author(s):  
Iriwi Louisa S. Sinon

<p><em>Study dendrochronology or tree-ring dating is defined as the study of chronological sequence of annual growth rings in trees. Teak (Tectona grandis) is one of various tree species that has been identified for the use of tree-ring studies in tropical regions. Teak is found to be suitable for dendrochronology as it is long-lived and develops defined annual growth rings. In Java, teak cans growth naturally or intensively in plantation. The two silviculture conditions will give different sensitivity on climate effect. Therefore, the effect of silviculturer will on natural teak and plantation teak in Saradan, Madiun, and East Java. As a part of the study, ten core samples from natural- growth teak were measured. The samples of growth rings is spanned from 1832 – 2004. Using the COFECHA program, the correlation of the samples (r) was found to be 0.44 point, which is satisfactory to the standard used in dendrochronology. Thus, from this study it can be concluded that natural teak could still be used in dendrochronology, although the sensitivity are not as high as plantation teak. </em></p>


2017 ◽  
Author(s):  
Jocelyn Raude

Objectives: Although people have been repeatedly found to underestimate the frequency of risks to health from common diseases, we still do not know much about reasons for this systematic bias, which is also referred to as “primary bias” in the literature. In this study, we take advantage of a series of large epidemics of mosquito-borne diseases to examine the accuracy of judgments of risk frequencies. In this aim, we assessed the perceived versus the observed prevalence of infection by zika, chikungunya or dengue fever during these outbreaks, as well as their variations among different subpopulations and epidemiological settings.Design: We used data drawn from 4 telephone surveys, conducted between 2006 and 2016, among representative samples of the adult population in tropical regions (Reunion, Martinique, and French Guiana). The participants were asked to estimate the prevalence of these infections by using a natural frequency scale.Results: The surveys showed that (1) most people greatly overestimated the prevalence of infection by arbovirus, (2) these risk overestimations fell considerably as the actual prevalence of these diseases increased, (3) the better-educated and male participants consistently yielded less inaccurate risk estimates across epidemics, and (4) that these biases in the perception of prevalence of these infectious diseases are relatively well predicted by probability weighting function.Conclusions: These findings suggest that the cognitive biases that affect perception of prevalence of acute infectious diseases are not fundamentally different from those that characterize other types of probabilistic judgments observed in the field of behavioral decision-making. They also indicate that numeracy may play a considerable role in people’s ability to transform epidemiological observations from their social environment to more accurate risk estimates.


2007 ◽  
Vol 2 (1) ◽  
Author(s):  
Petia Mijaylova Nacheva ◽  
G. Moeller-Chávez ◽  
E. Ramírez-Camperos ◽  
L. Cardoso-Vigueros

The tropical regions have specific problems associated with high pathogenic density in the sewage sludge. The aim of this study was to select an adequate sludge stabilization and valorization system comparing the performance of four technologies: anaerobic stabilization without heating, aerobic stabilization, alkaline treatment with lime and aerobic composting. The study was performed in a pilot plant which was built and operated during six months. The main problem for the beneficial use of the sludge was its pathogenicity. All the systems allowed obtaining stabilized products which met the bacteriological criteria for some kind of use. The compost and the alkalinized sludge were bacteriologically safe for use without restrictions in accordance with the Mexican regulations. The accomplishment of the parasitological criteria for use was however impossible with the anaerobic and with the aerobic systems. The compost obtained at 55-60°C with 25d aeration time and the alkaline sludge fulfill the criteria established by for forest and agriculture use and for soil conditioning. The composting could reach the requirements for unrestricted use when operated at temperatures 65-70°C during 45 days which makes it the most adequate sludge treatment system for hot climate regions.


2019 ◽  
Vol 25 (12) ◽  
pp. 1430-1439 ◽  
Author(s):  
Isabela Ribeiro Pinto ◽  
Hellíada V. Chaves ◽  
Auriana S. Vasconcelos ◽  
Francisca Clea F de Sousa ◽  
Tatiane Santi-Gadelha ◽  
...  

Ethnopharmacological Relevance:Mucuna pruriens (Mp) belongs to Leguminosae family, it is native of tropical regions and used to treat several maladies such as urinary, neurological, and menstruation disorders, constipation, edema, fever, tuberculosis, ulcers, diabetes, arthritis, dysentery, and cardiovascular diseases. Mp seeds are rich in bioactive compounds, for instance, lectins, a heterogeneous group of proteins and glycoproteins with a potential role as therapeutic tools for several conditions, including gastric disorders. This study investigated the acute toxicity, gastroprotective, and antioxidant activities of a lectin from Mucuna pruriens seeds (MpLec) on ethanol-induced gastropathy model in mice.Materials & Methods:Mice received MpLec (5 or 10 mg/kg; i.v.) and were observed for acute toxicity signs; in another experimental series, mice were pre-treated with MpLec (0.001; 0.01 or 0.1 mg/kg, i.v.), ranitidine (80 mg/kg, p.o.), or saline (0.3 mL/30g, i.v.) before ethanol 99.9% (0.2 mL/animal, p.o.), and euthanized 30 min after ethanol challenge. Macroscopic and microscopic gastric aspects, biochemical parameters (tissue hemoglobin levels, iron-induced lipid peroxidation, GSH content, SOD activity, and gastric mucosal PGE2) were measured. Additionally, pharmacological tools (yohimbine, indomethacin, naloxone, L-NAME) were opportunely used to clarify MpLec gastroprotective mechanisms of action.Results:No toxicity signs nor death were observed at acute toxicity tests. MpLec reduced ethanol-induced gastric damage, edema, and hemorrhagic patches formation, as well as decreased lipid peroxidation, SOD activity, and increased GSH content. Yohimbine and indomethacin prevented MpLec effects, suggesting the involvement of alpha-2 adrenoceptors and prostaglandins in the MpLec-mediated effects.Conclusion:MpLec does not present toxicity signs and shows gastroprotective and antioxidant activities via alpha-2 adrenoceptors and prostaglandins in the ethanol-induced gastropathy model.


2020 ◽  
Vol 20 (7) ◽  
pp. 566-577 ◽  
Author(s):  
Amlan Kumar Patra

Natural plant bioactive compounds (PBC) have recently been explored as feed additives to improve productivity, health and welfare of poultry following ban or restriction of in-feed antibiotic use. Depending upon the types of PBC, they possess antimicrobial, digestive enzyme secretion stimulation, antioxidant and many pharmacological properties, which are responsible for beneficial effects in poultry production. Moreover, they may also improve the intestinal barrier function and nutrient transport. In this review, the effects of different PBC on the barrier function, permeability of intestinal epithelia and their mechanism of actions are discussed, focusing on poultry feeding. Dietary PBC may regulate intestinal barrier function through several molecular mechanisms by interacting with different metabolic cascades and cellular transcription signals, which may then modulate expressions of genes and their proteins in the tight junction (e.g., claudins, occludin and junctional adhesion molecules), adherens junction (e.g., E-cadherin), other intercellular junctional proteins (e.g., zonula occludens and catenins), and regulatory proteins (e.g., kinases). Interactive effects of PBC on immunomodulation via expressions of several cytokines, chemokines, complement components, pattern recognition receptors and their transcription factors and cellular immune system, and alteration of mucin gene expressions and goblet cell abundances in the intestine may change barrier functions. The effects of PBC are not consistent among the studies depending upon the type and dose of PBC, physiological conditions and parts of the intestine in chickens. An effective concentration in diets and specific molecular mechanisms of PBC need to be elucidated to understand intestinal barrier functionality in a better way in poultry feeding.


2020 ◽  
Vol 06 ◽  
Author(s):  
Saheed Sabiu ◽  
Christiana Eleojo Aruwa ◽  
Viresh Mohanlall ◽  
Himansu Baijnath

Background: Momordica balsamina L. is a monoecious climbing vine and perennial herb native to the tropical regions of Asia, Arabia and the Caribbean, and with prominent presence in Nigeria, Botswana, Namibia, Swaziland and Southern African provinces. While evidence of its anecdotal usage as medicine exist, scientific reports complementing the claims are still emerging or at their infancy. Objective: This review appraised the morphology, therapeutic and biotechnological significance of M. balsamina. Method: Online resources such as Google Scholar, PubMed, ScienceDirect and MeSH were utilized for literature search and included relevant information from inception till May 2020 to streamline sought outcomes for in-depth discussion. Results: The data gathered and considered worthy of inclusion in this study revealed that M. balsamina is rich in phytonutrients of medicinal significance with cucurbitane-type triterpenoids, balsamin and momordins well characterized and fully elucidated. These compounds and other novel bioactive agents in M. balsamina have found remarkable pharmacological relevance and could further be harnessed for use against several debilitating human disorders. Conclusion: The potential applications of M. balsamina as nutraceutical and pharmaceutical agent should not be undermined. Also, with the inadequate toxicological data on this wild species, its consumption should be with caution and translational studies that could advance scientific knowledge and aid better understanding of both its pharmacokinetics and pharmacodynamics without sidelining its potent biotechnological applications are highly encouraged. It is hoped that this paper will provide baseline information that could serve as a guide and inspiration for further studies on the prospects of M. balsamina.


Sign in / Sign up

Export Citation Format

Share Document