Estimating gene action,combining ability and heterosis for grain yield and agronomic traits in extra-early maturing yellow maize single-crosses under three agro-ecologies of Ghana     

G. A. Owusu  D. Nyadanu  K. Obeng-Antwi  R. Adu Amoah  F. C. Danso  S. Amissah 《Euphytica》2017,213(12):287

Maize (Zea mays L.) is the most important cereal crop produced in Ghana. However, yield of the crop is generally low, producing just about 1.7 t/ha. The low yield is attributed to continuous use of local/unimproved varieties. Generally, hybrid varieties have proven to out-yield the local/unimproved varieties due to improved vigour. Development of hybrid varieties depend on good understanding of combining ability and inheritance of important quantitative traits such as grain yield (GY). 45 half-diallel crosses generated from 10 extra-early maturing yellow inbred lines were evaluated in 2015 under rain-fed conditions. The objectives were to determine the genetic control, breeding value and estimate heritability for GY and agronomic traits of the inbred lines under contrasting growing environments in Ghana. General combining ability (GCA) and specific combining ability (SCA) were important in the inheritance of GY and agronomic traits of the inbred lines. However, GCA was more important than SCA across environments to suggest that additive gene action was more important than non-additive gene action in the inheritance of GY and agronomic traits in the inbred lines. High broad-sense heritability, for GY and other agronomic traits indicated preponderance of additive gene action in trait expression, thus, selection based on phenotypic expression could be feasible. Inbred lines P1, P4 and P8 were good combiners for high GY. The genotype, P4 × P8, was identified as the ideal and most yielding single-cross hybrid across research environments and should be further tested on-farm before commercialization.  相似文献   

Underplanting oil palm with cocoa in Ghana     

F. M. Amoah  B. N. Nuertey  K. Baidoo-Addo  F. K. Oppong  K. Osei-Bonsu  T. E. O. Asamoah 《Agroforestry Systems》1995,30(3):289-299

Mature oil palms at the Oil Palm Research Institute at Kusi, Ghana were underplanted with cocoa to study the feasibility of mixed cropping of the two crops under West African conditions. The oil palm trees used in this trial were planted in 1970 and had achieved maximum canopy formation. Three triangular spacings of the oil palms used were 8.7, 9.9 and 10.5 m. The cocoa was underplanted in June 1988 at a spacing of 2.4 m triangular using mixed hybrids. There were no significant differences in oil palm yield between plots with cocoa and the controls. There was no appreciable damage to the cocoa trees from falling palm fronds and fruits during harvesting or pruning. Cocoa seedling growth and yield were significantly better under the oil palm spaced at 9.9 or 10.5 m triangular than under oil palm space at 8.7 m triangular.  相似文献   

Factors influencing growth of Canadian Holstein calves in Ghana     

J. D. Kabuga  Kwaku Agyemang 《Tropical animal health and production》1983,15(3):186-190

Factors thought to influence monthly body weight and average daily gain of 122 first and second generation Canadian Holstein calves aged six to 24 months were studied. All factors (generation, sex, parity, season, age and year) studied accounted for 55.9 to 71.2% and 35.6 to 69.1% of the variation in body weight and average daily gain respectively. Parity, year and generation were the most important factors influencing all traits and accounted for 34.4 to 64.3% and 22.9 to 66.8% of the variation in body weight and average daily gain. Least squares means were, for body weight 144.2, 222.6, 330.5 and 377.9 kg at six, 12, 18 and 24 months and for average daily gain 0.42, 0.37, 0.50 and 0.39 kg at six to nine, nine to 12, 12 to 18 and 18 to 24 month intervals. It was concluded that offspring of Canadian Holsteins in this environment under adequate management and nutrition will be of adequate size for heifers to calve under 30 months of age and steers to reach 400 kg slaughter weight in 24 months.  相似文献   

Evaluation of different dietary additives based on growth performance,innate immunity and disease resistance in juvenile Amur catfish,Silurus asotus     

Yaa Tiwaah Amoah  Mohammad Moniruzzaman  Seunghan Lee  Jinho Bae  Seonghun Won  Minji Seong  Sungchul C. Bai 《International Aquatic Research》2017,9(4):351-360

Three different dietary additives were evaluated based on growth performance, innate immune responses and disease resistance in juvenile Amur catfish Silurus asotus. Four diets were prepared by supplementing 0.4% Song-gang® stone (SG), 0.05% Yucca meal (YM), 0.05% β-glucan (BG) in combination with 0.04% SG and 0.05% BG (SG + BG) to a basal commercial diet (control; CONT). Triplicate groups of fish averaging 4.95 ± 0.05 g were fed one of the test diets between 3 and 5% body weight for 8 weeks. At the end of the feeding trial, weight gain, specific growth rate, feed efficiency and protein efficiency ratio of fish fed SG and SG + BG were significantly higher than those of fish fed the BG and CONT diets (P < 0.05). Lysozyme activity in fish fed the SG, YM, and SG + BG diets was significantly higher than those of fish fed the CONT diet. Super oxide dismutase (SOD) activity was significantly higher among fish fed the SG, YM, BG and SG + BG diets than fish fed the CONT diet. After 14 days challenge test with Edwardsiella tarda, cumulative survival rates of fish fed the SG and SG + BG diets were significantly higher than those of fish fed the BG and CONT diets. Results revealed that dietary SG or SG + BG diets had positive responses over other additives in juvenile Amur catfish. However, Song-gang® stone is proposed to be a cheaper dietary additive contributing 0.04 cents/kg of feed based on economic point of view.  相似文献   

Administration of probiotic Bacillus licheniformis induces growth,immune and antioxidant enzyme activities,gut microbiota assembly and resistance to Vibrio parahaemolyticus in Litopenaeus vannamei     

Kwaku Amoah  Xiao‐hui Dong  Bei‐ping Tan  Shuang Zhang  Shu‐yan Chi  Qi‐hui Yang  Hong‐yu Liu  Yuan‐zhi Yang  Hai‐tao Zhang 《Aquaculture Nutrition》2020,26(5):1604-1622

This study aimed to elucidate the effects of dietary Bacillus licheniformis ATCC 11946 (BL) on the growth, immune and antioxidant activities, intestinal morphology and microbiota, and susceptibility to Vibrio parahaemolyticus (VP_AHPND) in juvenile pacific white shrimp, Litopenaeus vannamei (LV). Juvenile LV (initial weight = 0.63 ± 0.001) were fed diets containing varying BL concentrations (0 (BL0), 10⁶ (BL1), 10⁷ (BL2) and 10⁸ (BL3) CFU/g feed) for 8 weeks. Growth performance, immune and antioxidant enzyme activities, and intestinal morphology significantly improved in the probiotic‐treated groups than the untreated. Regardless of the treatment group, the two dominant phyla were Proteobacteria and Bacteroidetes, whereas the two dominant genera were Ruegeria and Vibrio. Increasing inclusion of probiotics in diets led to significant increase in beneficial bacterial genera (Ruegeria, and Pseudoalteromonas) and a significant decrease in some known opportunistic pathogens (Vibrio, Tenacibaculum, Photobacterium, Kangiella and Spongiimonas) with the BL3 group witnessing the best. A 7‐day challenge study with VP_AHPND showed significantly high protection in the probiotic‐treated groups, with the BL3, BL2 and BL1 obtaining 51%, 34% and 22% relative percentage survival, respectively. In conclusion, BL at 10⁸ CFU/g feed should be used to help in shrimp production since it attained the most significant improvement.  相似文献   

Comparison of density and selected microscopic characteristics of stem and branch wood of two commercial trees in Ghana     

Peter Kessels Dadzie  Martin Amoah  Kwasi Frimpong-Mensah  Sheldon Q. Shi 《Wood Science and Technology》2016,50(1):91-104

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Phenolic Content,Antioxidant Activity,and Consumer Acceptability of Sorghum Cookies     

Constance Chiremba  John R. N. Taylor  Kwaku G. Duodu 《Cereal Chemistry》2009,86(5):590-594

Cookies were produced from different sorghum flours to determine their potential as vectors of antioxidants. Different sorghum cultivars and their flour extraction rates were evaluated for their effects on phenolic content and antioxidant activity of the cookies. Consumer acceptance of the sorghum cookies was compared with that of wheat flour cookies. For each sorghum cultivar, cookies of 100% extraction rate flours had two to three times more total phenolics compared with those of 70% extraction rate flours, while antioxidant activity was 22–90% higher. Cookies of the condensed tannin sorghum had two to five times more phenolics compared with those of condensed tannin‐free sorghum. Antioxidant activity was 145–227 μMol Trolox equivalents (TE)/g in cookies of condensed tannin sorghum compared with 10–102 μMol TE/g in those of condensed tannin‐free sorghum. The sorghum flours had slightly higher phenolic content and antioxidant activity values than their corresponding cookies. Cookies of the red tannin‐free sorghum flours (PAN 8564/8446) were equally liked as wheat flour cookies, except for texture. However, cookies of condensed tannin sorghum were least accepted compared with wheat flour cookies despite their high antioxidant activity.  相似文献   

Performance of canadian holstein-friesian cattle in the humid forest zone of Ghana     

J. D. Kabuga  Kwaku Agyemang 《Tropical animal health and production》1984,16(2):85-94

Summary One hundred and three calving records of 35 Canadian Holstein-Friesian cattle introduced in 1974 into Ashanti constituted the data for this study. Age, year, lactation number, season and age × season effects on 305-day yield, lactation length and components of the lactation curve were estimated from 84 complete lactation records.Analysis of variance by General Linear Models Procedure showed significant effect of age and year on all traits studied. Age, year, lactation number, season, concentrate fed and season × age accounted for 61.1, 64.6, 66.9, 68.5 and 38.1% of the variation in 305-day yield, 300-day yield, monthly peak yield, persistency index and lactation length respectively. Age and year significantly affected all traits except lactation length. Lactation number only significantly affected 305-day yield of the traits studied. Season was not an important factor affecting any of the traits. The productive life span of the animals was up to five calvings (eight years). The mean life time milk production was 16,186 kg. Unadjusted means of the 103 records were: 305-day yield 3,878 ± 93.7 kg; actual 305-yield 4,451 ± 102.7 kg; total yield 4,225 ± 160.6 kg; lactation length 332 ± 14.5 days; days dry 96 ± 5.9 and total yield per day of calving interval 10.6 ± 0.33 kg. Performance of Holsteins in Ashanti was better than in most tropical areas.

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Productividad Del Ganado Holstein-Friesian Canadiense En La Zona Boscosa Humeda De Gana. I. Produccion De Leche

Resumen Los datos para este estudio, salieron de 103 registros de pariciones pertenecientes a 35 Holstein-Friesian Canadienses, introducidas a Ashanti en 1974. Se estimaron la edad, año, número de lactancias, estación y edad × effectos estacionales 305 días de producción, duración de la lactancia y componentes de la curva de lactancia, con base en 84 registros completos de lactancia.El análisis de varianza, efectuado por el procedimiento de Modelos Generales Lineares, mostró efectos significativos de edad y años sobre todos los rasgos estudiados. La edad, año, número de lactancias, estación, alimento concentrado y estación × edad, influyeron en 61.1, 64.6, 66.9, 68.5 y 38.1% de la variación en 305 días de producción, 300 días de producción, pico mensual de producción, índice persistente y duración de la lactancia, respectivamente. La edad y el año afectaron significativamente todos los rasgos, excepto la duración de la lactancia. El número de lactancias solo afectó significativamente la producción de 305 días, de todos los rasgos estudiados. La estación tampoco fué factor importante para los rasgos. La vida productiva de los animales estuvo por encima de las 5 pariciones (8 años). La media de producción de leche durante la vida productiva, fué de 16.186 kg. Las medias sin ajustar de los 103 registros fueron; producción de 305 días 3.878±93.7 kg; producción actual de 305 dias 4.451±102.7 kg; producción total 4.225±160.6 kg; duración de la lactancia 332±14.5 días; días secas 96±5.9 y producción total por día de intervalo de parto 10.6±0.33 kg. La productividad de las Holstein en Ashanti, fué superior a la de la mayoría de áreas tropicales.

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Performances De Bovins Canadiens Holstein-Frisons En Zone Forestiere Humide Au Ghana. I. Production Laitiere

Résumé 103 relevés de vêlage de 35 bovins canadiens Holstein-Frisons importés en 1974 à Ashanti ont fourni les données de cete étude. L'âge, l'année, le nombre de lactations, la saison, les effets conjugués de l'âge et de la saison sur une production de 305 jours, la durée de la lactation et les composantes de la courbe de lactation ont été évalués à partir de 84 relevés de lactation complète.L'analyse de variance par le modèle linéaire général a montré que l'âge et l'année avaient un effet significatif sur tous les paramètres étudiés. L'âge, l'année, le nombre de lactations, la saison, le concentré donné et l'effet saison/âge étaient responsables de 61,1; 66,9; 68,5 et 38,1 p.100 de la variation pour respectivement une production de 305 jours, une production de 300 jours, les pointes de production mensuelle, l'index de persistance et la durée de lactation. L'âge et l'année avaient un effet significatif sur toutes les performances sauf la durée de lactation. Le nombre de lactations n'avait un effet significatif que sur la production de 305 jours des traits zootechniques étudiés. La durée de vie productive des animaux allait jusqu'au cinquième vêlage (8 ans). La production laitière moyenne sur un temps de vie a été évaluée à 16 186 kg. Les moyennes non-ajustées des 103 relevés ont été les suivantes: production de 305 jours: 3878±93,7 kg; production de fait de 305 jours: 4451±102,7 kg; production totale: 4255±160,6 kg; durée de lactation: 332±14,5 jours; jours de tarrissement: 96±5,9 et production totale journalière pendant l'interval entre vêlages: 10,6±0,33 kg. Les performances des Holstein à Ashanti ont été meilleures que dans la plupart des régions tropicales.

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The effect of male proximity on vaginal patency,estrous cycle length and feed intake of female grasscutters     

John Kormla Nyameasem  Emmanuel Kwadwo Adu  Kwame Owusu Amoah  Bernard Ato Hagan 《Tropical animal health and production》2016,48(2):445-449

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Effects of Graded Levels of Carbohydrate on Growth and Survival of Largemouth Bass, Micropterus salmoides     

Akua  Amoah  Shawn D.  Coyle  Carl D.  Webster  Robert M.  Durborow  Leigh Anne  Bright  James H.  Tidwell 《Journal of the World Aquaculture Society》2008,39(3):397-405

Excessive carbohydrates (CHO) in diets for largemouth bass (LMB), Micropterus salmoides, are suspected of accumulating glycogen in hepatocytes, which may result in liver dysfunction. This study evaluated the effect of graded levels of dietary CHO on growth, survival, and liver histology of LMB. One hundred feed‐trained advanced fingerling LMB (128.5 ± 21.5 g) were stocked into each of nine 3400 ‐ L polyethylene tanks. Tanks were randomly assigned one of three experimental diets containing different CHO levels (13, 19, or 25% of diet). The extruded diets were approximately isonitrogenous (42% crude protein) and isocaloric (3 kcal/g energy). There were three replicate tanks per dietary treatment. Bass were fed to apparent satiation twice daily for 148 d. Survival was significantly higher (P ≤ 0.05) for fish fed the 13 and 19% CHO diets (89 and 90%, respectively) compared to those fed the 25% CHO diets (82%). Average harvest weight of fish fed the 13% CHO diet (380 g) was significantly greater (P ≤ 0.05) than for fish fed other diets. Average harvest weight of fish fed the 19% CHO diet (347 g) was significantly greater (P ≤ 0.05) than for fish fed the 25% CHO diet (310 g). Specific growth rates (%/d) were significantly higher (P ≤ 0.05) in fish fed the 13 and 19% CHO diets than in fish fed 25% CHO diet. Feed conversion ratios for fish fed the 13 and 19% CHO diets (2.3 and 2.4, respectively) were both significantly lower (P ≤ 0.05) than in fish fed the 25% CHO diet (3.6). There were no significant differences (P > 0.05) in condition factor, protein efficiency ratio, hepatosomatic index, or liver glycogen concentration among fish fed the different experimental diets. Overall, mean blood glucose levels in fish fed the 13 and 19% CHO diets (61.0 and 71.2 mg/dL, respectively) were significantly lower (P ≤ 0.05) than in fish fed the 25% CHO diet (87 mg/dL). Histopathological examination of livers from fish fed the three diets was used to score the degree of vacuolization of hepatic tissues (0 = normal, 1 = slight, 2 = mild, 3 = moderate, and 4 = severe). Regression of vacuolization scores on dietary CHO levels was statistically significant (P ≤ 0.05) and indicated a direct positive relationship between liver vacuolization and dietary CHO level (R² = 0.57). These data indicate that LMB grow faster and use feeds more efficiently when CHO are maintained at <20% of diet. CHO levels >20% negatively impacted liver histology, but a liver tissue analyses did not document glycogen accumulation.  相似文献