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1.
Animal ; 15(2): 100106, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33712219

RESUMO

High environmental temperatures are a foremost concern affecting poultry production; thus, understanding and controlling such conditions are vital to successful production and welfare of poultry. In view of this, a completely randomized design with a 2 × 2 factorial arrangement involving two local strains (Kirin chicken (KC) and Three-yellow chicken (TYC)) and two temperature groups (normal/control = 30 ±â€¯2 °C and acute heat stress (AHS) = 35 ±â€¯1 °C for 8-h with 70% humidity) was used to assess the main regulatory factors such as heat shock protein (HSP70) gene, cytokine genes (IL-1ß, IL-6, IL-10), muscle development gene (IGF-1) and tissue histopathological changes. At 56 days old, the temperatures of the comb (CT), feet (FT), eyelid (ET) and rectal (RT) from each group were taken thrice at 0, 2, 4 and 8-h during AHS, and 1 and 3-h recovery period after AHS. At 80 days old, the slaughter weight was also analyzed. The CT and ET of the AHS groups increased during the 8-h trial, while the RT of both strains decreased significantly at 4 h but increased at 8 h in the TYC group. All temperature recordings dropped in the AHS groups of both strains during the recovery period. The results revealed that the mRNA expression of HSP70 in the liver was higher in the heat-stressed group of both strains compared to the control. The expression of HSP70 was shown in the AHS-KC group to be significantly high compared to the control (P < 0.05). Moreover, the IGF1 gene in the liver, breast muscle and leg muscle was downregulated in the AHS-TYC group compared to the control (P < 0.05), although that in the AHS-KC was downregulated in the breast muscle. The mRNA expression of spleen IL-1ß significantly decreased in the AHS-TYC group (P < 0.01), whereas that of the AHS-KC had no significant difference (P > 0.05). The mRNA expression of spleen IL-6 and IL-10 was increased in the AHS-KC group but did not exhibit obvious changes in the AHS-TYC. Correspondingly, the histopathological examinations revealed tissue injury in the AHS groups of both strains, with the TYC strain experiencing more severe changes. The final live and carcass weights showed a significant enhancement in the treatments (P < 0.01 and P < 0.05, respectively) and treatment×strain interaction (P < 0.05) with breast muscle rate significantly reducing among the treatments (P < 0.01) at 80 days. In conclusion, the differential response to AHS after physiological, molecular and immune response portrays KC to have better thermal tolerance than the TYC.


Assuntos
Galinhas , Transtornos de Estresse por Calor , Animais , Galinhas/genética , Proteínas de Choque Térmico HSP70/genética , Transtornos de Estresse por Calor/veterinária , Proteínas de Choque Térmico , Resposta ao Choque Térmico/genética , Temperatura Alta , Estresse Fisiológico
3.
PLoS One ; 15(5): e0232595, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374747

RESUMO

Cassava is the 6th most important source of dietary energy in the world but its root system architecture (RSA) had seldom been quantified. Ability to select superior genotypes at juvenile stages can significantly reduce the cost and time for breeding to bridge the large yield gap. This study adopted a simple approach to phenotyping RSA traits of juvenile and mature cassava plants to identify genotypic differences and the relationships between juvenile traits and harvest index of mature plants. Root classes were categorised and root and shoot traits of eight (8) juvenile pot-grown cassava genotypes, were measured at 30 and 45 days after planting (DAP). The same or related traits were measured at 7 months after planting of the same genotypes grown in the field while yield and yield components were measured in 12-months old field-grown plants. The field experiment was done in 2017 and repeated in 2018. Differences between genotypes for the measured traits were explored using analysis of variance (ANOVA) while traits in juvenile plants were correlated or regressed onto traits measured in 7- and 12-months old plants. The results show significant genotypic variations for most of the traits measured in both juvenile and 7-months old plants. In the 12-months old plants, differences between genotypes were consistent for both 2017 and 2018. Broad-sense heritability was highest for the number of commercial roots (0.87) and shoot fresh weight (0.78) and intermediate for the total number of roots (0.60), harvest index (0.58), fresh weight of roots (0.45). For all the sampling time points or growth stages, there were greater correlations between traits measured at a particular growth stage than between the same traits at different growth stages. However, some juvenile-mature plant trait relationships were significant, positive and consistent for both 2017 and 2018. For example, total root length and the total number of roots in 30 DAP, and branching density of upper nodal roots in 45 DAP, positively correlated with harvest index of 12-months old plants in both 2017 and 2018. Similarly, the diameter of nodal roots, for example, had a negative, significant correlation with fresh shoot biomass of mature plants in both 2017 and 2018. Regression of traits measured in 30 DAP explained up to 22% and 36% of the variation in HI of mature plants in 2017 and 2018, respectively. It is concluded that the simple, rapid, inexpensive phenotyping approach adopted in this study is robust for identifying genotypic variations in juvenile cassava using root system traits. Also, the results provide seminal evidence for the existence of useful relationships between traits of juvenile and mature cassava plants that can be explored to predict yield and yield components.


Assuntos
Manihot/crescimento & desenvolvimento , Melhoramento Vegetal , Variação Genética , Manihot/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Locos de Características Quantitativas
4.
Ghana Med J ; 49(3): 214-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26693198

RESUMO

Sickle cell disease (SCD) is a hereditary blood disorder characterized by abnormally shaped red cells. SCD frequently exhibits multisystemic manifestations including oral and craniofacial disorders. Craniofacial features such as maxillary protrusion and more forward growth of the mandible with significantly retruded maxillary and mandibular incisors are common. When a patient with Sickle Cell Disease (SCD) needs orthodontic treatment, it is important for the practitioner involved to know about the disease and the respective treatment because of the importance of complete blood supply after application of intraoral and extraoral forces. This article describes a sickle cell HbSS patient with orthodontic problems and how she was successfully managed at the University of Ghana Dental School.


Assuntos
Anemia Falciforme/terapia , Braquetes Ortodônticos , Adulto , Gerenciamento Clínico , Feminino , Gana , Humanos , Saúde Bucal
5.
Aust Orthod J ; 23(1): 36-40, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17679533

RESUMO

AIMS: To compare the static frictional resistance of ceramic brackets with a conventional slot (Allure), a glazed slot (Mystique) and a metal slot insert (Clarity). METHOD: Twenty five brackets of each type, with slot size 0.022 x 0.028 inch and Roth prescription were tested by sliding against straight lengths of 0.019 x 0.025 inch rectangular stainless steel wire. During the tests the brackets and wire were lubricated with artificial saliva. Static frictional forces at three different simulated binding angulations (0, 5 and 10 degrees) were measured for each type of bracket. RESULTS: At each of the angulations tested, the Clarity brackets produced the lowest static frictional resistance. At 0 degree angulation (below the critical angle for binding) the Allure brackets produced the greatest friction. The difference in friction between the Clarity and Mystique brackets was not statistically significant. As the angulations were increased to 5 degrees the Allure brackets again produced the greatest frictional resistance, although this was not significantly higher than the Mystique brackets. The Mystique brackets produced the greatest frictional resistance at 10 degrees, but again there was no statistical difference from the Allure brackets. CONCLUSIONS: A glazed slot ceramic bracket demonstrates low frictional resistance at non-binding angulations and compares favourably with a metal slot ceramic bracket. Increasing angulations through 5 to 10 degrees of simulated binding results in high levels of static frictional resistance such that the bracket behaves more like a conventional polycrystalline ceramic bracket.


Assuntos
Braquetes Ortodônticos , Fios Ortodônticos , Análise de Variância , Cerâmica , Análise do Estresse Dentário , Fricção , Desenho de Aparelho Ortodôntico
6.
Artigo em Inglês | MEDLINE | ID: mdl-10842839

RESUMO

The Danish International Development Agency (DANIDA) is assisting the government of Ghana to provide potable water and improved sanitation facilities to about 50% of the Volta Region's population over a 10-year Community Water and Sanitation Programme (CWSP). Sanitation options include designs for household Ventilated Improved Pit (VIP) latrines. However, areas along the coastal belt of the region have a high water table, between 1-1.5 m (3.3-4.95 ft). In addition, about 80% of the inhabitants in these areas depend on shallow hand-dug wells for domestic purposes and irrigation of vegetable gardens. With the construction of these sanitation options under promotion, pollution of the groundwater is inevitable. Circumventing the problem by the programme led to the modification of the present designs into the "Volta Watertight VIP Latrine (VVIP)". The design considerations and the components that have been incorporated to enable it function effectively are presented in this paper for discussion. Five (5) demonstration units were built, and used for a year. Used pits were covered and pit contents examined after a period of six months. Observations made at the end of this fallow led to the conclusion that the VVIP could be adapted for high water table areas to prevent groundwater pollution, baring any constructional defects and inefficiencies.


Assuntos
Países em Desenvolvimento , Engenharia Sanitária/instrumentação , Esgotos , Banheiros , Gana , Humanos , Microbiologia da Água , Abastecimento de Água/normas
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