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1.
1. Two experiments were conducted to develop naked neck (Na/na) and normal feathered (na/na) crossbreds and compare their growth performance, linear body measurements and carcass characteristics in the first and second filial generations.
2. In the first experiment, 4 indigenous naked neck males (Na/na) were mated to 36 Lohmann commercial females (na/na) in a ratio of 1:9. The two genotypes (Na/na, na/na) were allocated randomly according to batches of hatch, sire lines and sex to three different villages.
3. In the second experiment, 10 males and 100 females of F1 Na/na birds were selected and mated inter se in a ratio of 1:10. The three genotypes (Na/Na, Na/na and na/na) were compared in a randomised complete block design experiment, with the three villages, hatch and sex as blocks and the three genotypes as treatments. F1 Na/na birds had significantly higher (P < 0.05) feed conversion ratio, body weight, body weight gain, linear body measurements, survivability and carcass yield than their na/na counterparts.
4. In the F2 generation, Na/Na and Na/na birds had significantly higher (P < 0.05) feed conversion ratio, body weight, body weight gain, linear body measurements, survivability and carcass yield compared to their na/na counterparts.
5. The birds showing the naked neck phenotype appeared to show superior performance compared to normal feathered birds and could be exploited for potential utilisation in local poultry production. 相似文献
2.
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
3.
D. Nyadanu R. Akromah B. Adomako C. Kwoseh S. T. Lowor H. Dzahini-Obiatey A. Y. Akrofi M. K. Assuah 《Euphytica》2012,188(2):253-264
Black pod is a major disease of cocoa. Knowledge of the inheritance of resistance to black pod would be important in devising strategies to breed resistant varieties. The mode of inheritance of resistance to black pod disease was investigated using leaf disc, detached pod tests and natural field observation in a 6?×?4 factorial and 6?×?6 diallel mating designs analyzed using North Carolina design-II approach and Griffing??s method II model I approach, respectively. The dominant component was smaller than the additive component for pod lesion size, leaf disc scores and natural field infection. Both general combining ability and specific combining ability (SCA) effects influenced the inheritance of pod lesion number and leaf disc scores suggesting that both additive and non-additive (dominance or epistatic) effects influence the inheritance of resistance to black pod disease. However, SCA effect was not significant for pod lesion size and natural field infection suggesting the importance of additive genes in the inheritance of these traits. The higher heritability of leaf disc scores, pod lesion numbers and pod lesion sizes than the heritability of natural field infection which was almost zero, shows the influence of environment on natural field infection and suggests that ranking of resistance of cocoa genotypes need to be done under controlled environmental conditions to observe true resistance levels. Good general combiners, in combination with each other, did not necessarily yield good specific combinations suggesting that parents?? performance cannot be used for selecting superior progenies. The non-significance of reciprocal effects indicates absence of maternal effects or cytoplasmic inheritance in resistance to black pod disease. Recurrent selection procedures and inter-crossing aimed at general combining ability would be more suitable for improvement of black pod disease resistance. Cocoa genotypes with good combining ability for resistance to black pod disease such as T60/887, Pa 150, Sca 6, and Pa7/808, identified in this study could be important parents to form base population for such recurrent selection procedures. 相似文献
4.
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 (VPAHPND) 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 VPAHPND 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
5.
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
6.
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.
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.
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.相似文献
7.
Differences were found in the expression of resistance of perennial ryegrass, Lolium perenne, cultivars to crown rust, Puccinia coronata Corda, when plants were incubated at either 10°C or 25°C. In an extreme example, all the genotypes of ‘Carrick’ were resistant at 10°C but susceptible at 25°C. The variation between cultivars was due both to a general increase in expression of susceptibility and the proportion of plants which became susceptible. A BC1 line containing a stay‐green gene derived from Festuca pratensis was insensitive to temperature, while a sister line was sensitive. 相似文献
8.
Muthulisi Siwela John R. N. Taylor Walter A. J. de Milliano Kwaku G. Duodu 《Cereal Chemistry》2007,84(2):169-174
Grain of 22 finger millet types obtained from Southern and East Africa were analyzed to determine the influence of grain type on tannins, antioxidant properties, and tannin localization in the grain. Four grain types were creamy white and 18 were brown. A high proportion (80–100%) of kernels of all but two of the pigmented types stained black with the bleach test, while the light types did not stain black. There was a wide range of total phenolics, condensed tannin content, and antioxidant activity across the grain types. Light-colored grain types had much lower total phenolics and tannins relative to the pigmented types, and types that stained black with the bleach test had much higher tannin content and much higher antioxidant activity. Light microscopy revealed that kernels that stained black with the bleach test and had high tannin content had a dark-colored testa layer, indicating that the tannins were located in that layer as in sorghum. This is the first report that the bleach test can be used to detect tannin in finger millet types. The work demonstrates that occurrence of tannins in finger millet grain is a varietal property, as in sorghum. 相似文献
9.
Julius K. Hagan Kwaku Adomako Simon Oscar Olympio 《Tropical animal health and production》2014,46(1):107-111
A breed development strategy aimed at making exotic layers (Lohmann Brown) more productive under tropical environment using thermo-regulatory genes is underway at Akate Farms in Kumasi, Ghana. The present experiment was carried out to find out the effect of the genes on egg production in hot and humid environments. Three genetic groups comprising naked-neck, frizzle and their normally feathered sibs were obtained after successive generations of crossing between naked-neck and frizzle cocks and Lohmann brown hens. A total of 270 18-week-old pullets, 90 each of the 3 groups, were selected randomly and assigned to a completely randomized design experiment with 3 replicates, with 30 birds in each replicate group and kept up to a period of 72 weeks. The birds were kept in a partitioned open-sided deep-litter house constructed with sandcrete blocks with 30 pullets in each compartment. They were fed ad libitum with layer diets containing 18 % crude protein and 2,800 kcal ME/kg. Results obtained showed that the crossbred naked-neck and frizzle phenotypes produced eggs at a significantly (P?<?0.05) higher rates than their normally feathered sibs and also out-performed their normally feathered sibs in other egg production parameters measured, even though they all segregated from similar parents. This is an indication of the favourable effect of the genes on egg production under hot and humid environments. 相似文献
10.
Summary Birth weights, weaning weights and average daily gains of 97 calves born to 27 Holstein-Friesians imported from Canada were used. Adjusted mean birth weight, weaning weight and daily gain were 35.6, 104.6 and 0.5 kg respectively. Of the three variables studied sex of calf significantly influenced only birth weight whereas season of birth, sire of calf, parity of dam and year of birth significantly influenced weaning weight and daily gain but not birth weight. Sex, season, sire, parity and year all together accounted for 18.35, 43.49 and 46.09% of the variation in birth weight, weaning weight and daily gain respectively. Birth weight increased by 0.29 kg/day increase in gestation length and 0.027 kg/kg increase in calving weight, whereas weaning weight increased by 1.31 kg/kg increase in birth weight. Birth weights, weaning weights and daily gains observed here are similar to previous reports from other tropical environments.
Productividad Del Ganado Canadiense Holstein-Friesian En La Zona Boscosa Humeda De Gana. II. Productividad Antes Del Destete
Resumen Se utilizaron los pesos al nacer, al destete y el promedio de ganancia diaria de 97 terneros nacidos de 27 Holstein-Friesians importadas del canada. Las medias ajustadas de peso al nacer, peso al destete y la ganancia diaria de peso fueron: 35.6, 104.6, y 0.5 kg respectivamente. De las 3 variables estudiadas, el sexo de los animales influenció significativamente los pesos al nacer; mientras que la estación del año al nacer, sire y paridad de la madre y año de nacimiento, influenciaron significativamente el peso al destete y la ganancia diaria de peso, pero nó el peso al nacer. El sexo, estación, sire, paridad de la madre y año, en conjunto, influyeron en 18.35, 43.49 y 46.09% de la variación de peso al nacer, al destete y en la ganancia de peso diaria respectivamente. Los pesos al nacer se incrementaron 0.29 kg por incrementó día en duración de la gestación y 0.027 kg por incremento de kg en peso al nacer; mientras el peso al destete se incrementó 1.31 kg por incrementó de kg en peso al nacer. Los pesos al nacer, al destete y la ganancia diaria de peso observadas aquí, son similares a aquellas publicadas en otros informes de trabajos en condiciones tropicales.
Performances De Bovins Canadiens Holstein-Frisons En Zone Forestiere Humide Au Ghana. II. Performances Avant Sevrage
Résumé Les poids de naissance, les poids au sevrage et les gains journaliers moyens de 97 veaux nés de 27 Holstein-Frisons importés du Canada ont été utilisés. Le poids de naissance moyen ajusté, le poids au sevrage et le gain de poids journalier étaient respectivement de 35,6; 104,6 et 0,5 kg. Sur les trois variables étudiées, le sexe du veau avait seulement une influence significative sur le poids de naissance tandis que la saison de mise bas, le père du veau, le range de gestation influençaient de façon significative le poids au sevrage et le gain journalier mais non le poids de naissance. Le sexe, la saison, le père, le rang de gestation et l'année réunis étaient responsables de 18,35; 43,49 et 46,09 p. 100 des variations respectives du poids au sevrage et du gain journalier. Le poids de naissance a augmenté de 0,29 kg par jour supplementaire de durée de la gestation et de 0,027 kg par kg supplémentaire du poids de mise bas tandis que le poids de sevrage a augmenté de 1,31 kg par kg supplémentaire du poids de naissance. Les poids de naissance, les poids de sevrage et les gains journaliers observés ici sont semblables aux observations faites précédemment dans d'autres milieux tropicaux.相似文献