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11.
Reports on the nutritional composition of cowpea leaves have been limited to a small number of lines and the palatability characteristics of leaves apparently have not been studied. This study was therefore undertaken on cowpea leaves to determine the nutrient composition of fifteen varieties and the sensory attributes of ten varieties grown in Ghana. Nutritional components studied were moisture, protein, phosphorus and ascorbic acid. The sensory attributes included leaf size, taste and overall acceptability. There were significant (p > 0.05) differences among varieties in all nutrient components (fresh and dry weight basis), leaf size and overall acceptability. The nutrient composition values, on a dry weight basis, ranged from 9.4 to 13.0% for moisture, 303.8 to 468.9 mg/100 g for phosphorus, 33.5 to 148.0 mg/100 g for ascorbic acid, and 27.1 to 34.7% for protein. Differences in the sensory scores of leaves for taste were not significant (p < 0.05). Overall acceptability positively correlated with leaf size. Moisture content was negatively correlated with overall acceptability, phosphorus and ascorbic acid. Results can be exploited in a breeding program to develop nutritionally superior and acceptable cowpea varieties which can be used for harvesting of both leaves and seeds.  相似文献   
12.
Abstract Diel changes in littoral fish assemblage were studied in four reservoirs in the Czech Republic (Central Europe). The sampling was performed by beach seining in an unstructured littoral zone. Perch, Perca fluviatilis L., roach, Rutilus rutilus (L.), bream, Abramis brama (L.), carp, Cyprinus carpio L., ruffe, Gymnocephalus cernua (L.), pikeperch, Sander lucioperca (L.), eel, Anguilla anguilla (L.) and A. brama × R. rutilus hybrids exhibited higher densities at night. Only bleak, Alburnus alburnus (L.) exhibited higher densities during the day. The number of species was higher in night hauls, and mean body size of roach and bleak was also higher at night. Diel changes in fish densities resulted in the change in species composition between day and night. The study has implication for the sampling design to assess littoral fish assemblages using beach seine netting and recommends night sampling for a representative assessment or sampling during both diel periods for a robust assessment.  相似文献   
13.
Three different batches of Thaumatococcus danielli (Benth) fruits were collected at different fruiting seasons. The proximate compositions of the pericarp and seeds were determined on a dry weight basis. Partial characterization of the lipid extract was carried out and tannin content determined. The average moisture, ash and lipid contents of the pericarp were higher (89.2 ± 4.17%, 20.7 ± 1.10% and 11.6 ± 1.23%, respectively) than those of the seed (31.2 ± 4.66% 9.1 ± 0.71% and 8.2 ± 1.64%, respectively). Crude protein and total carbohydrate were, however, higher in the seed (9.5 ± 4.38% and 69.4 ± 11.52%, respectively) than in the pericarp (4.5 ± 2.21% and 6.3 ± 3.94%, respectively). The dietary fiber contents of both pericarp and seed were high. Starch content was very low in the pericarp (0.4 ± 0.0%) compared to the seed (66.28 ± 9.21%). Tannin content in the pericarp and seeds was 12.1 ± 1.52 mg/g and 21.9 ± 2.28 mg/g, respectively. The oil extracted from both pericarp and seeds was light-yellow in color and slightly solid at room temperature. Unsaturation level of T. danielli oil was low, while free fatty acids were high. The results obtained suggested that T. danielli waste could potentially be a raw material in livestock feed formulation.  相似文献   
14.
15.

The study evaluated the feeding behavior of growing male grasscutters (Thryonomys swinderianus) fed freshly cut Panicum maximum, supplemented with pelletized concentrates containing varying levels of dietary fiber. In a two-stage 4?×?4 Latin square arrangement, the relationships between water and dry matter intakes as influenced by dietary characteristics were investigated by offering supplements either at 09:00 h (morning) during the first stage or at 17:00 h (evening) during the second. Each test period lasted for 14 days with a 1-week rest period between changeovers. Time of feeding significantly (P?< 0.05) affected total dry matter intake (DMI) and intake of the supplements, with the total DMI increasing by 21% when the diets were offered in the evening relative to when offered in the morning. Regression analyses showed significant (P?<?0.05) correlations between dry matter (DM) and water intakes against some dietary characteristics. The current study has shown that crude fiber (CF) inclusion of up to 14% in pelletized supplements for growing grasscutters consuming a basal diet with CF up to 31% may not affect feed and water intake, as well as acceptability of the feed. However, feeding such supplements in the evening could stimulate higher feed intake. Also, dietary DM better predicted DMI compared to the other dietary characteristics.

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16.
The efficacy of the two most common techniques used for determining the sex of the greater cane rat, Thryonomys swinderianus, Temminck, was tested using 10 young and 8 adult animals with two technicians at the Animal Research Institute's Grasscutter Domestication Centre, Pokoase, Ghana. The techniques compared were the use of the head shape and/or head size and the use of the ano-genital distance. The use of the ano-genital distance for sex determination was validated in a colony of greater cane rats at various stages of development, i.e. from the day of birth to three or more years of age. The ano-genital distance was then used as the standard against which the use of the head shape and/or head size technique was tested. The results indicated that the use of the ano-genital distance for sex determination in the greater cane rat was error-free, even with little experience on the part of the practitioner. The ano-genital distance was more than twice as long in the males than in the females at all ages (p<0.001). However, the use of the head shape and/or head size for sex determination was found to be associated with some degree of error in both sexes. The use of the ano-genital distance can therefore be recommended as an efficacious technique for sex determination in the greater cane rat.  相似文献   
17.
The purpose of this study was a comprehensive survey on the occurrence and distribution of the viruses affecting almond nursery trees in western Anatolia (Turkey). Three provinces (Aydýn, Balýkesir and Ýzmir) which are well known for their state and commercial nursery plantations of almond (mixed with other stone fruits) were visited and 19 300 and 19 000 almond nursery trees were surveyed in 1992 and 1993, and 56 and 40 leaf samples collected, respectively. The main viral symptoms were chlorotic and necrotic spots, calico, mosaic, narrowing and deformation of the leaves; gummosis, weak growth, dwarfing and short internodes of the trees. DAS-ELISA was used to detect prunus necrotic ringspot ilarvirus (PNRSV), prune dwarf ilarvirus (PDV), raspberry ringspot nepovirus (RRV), peach rosette mosaic nepovirus (PRMV) and tomato ringspot nepovirus (ToRSV) in almond nursery trees in west Anatolia. PNRSV was found to be the most widespread according to ELISA. PDV was the second most important virus, and some samples were infected with both ilarviruses. Fewer samples were found infected with PRMV, RRV and only a few samples were infected with ToRSV.  相似文献   
18.
The association between conception rate at first service and numbers of follicles developed during a follicular wave was examined in 102 suckled beef cows and 14 heifers. Follicular development was monitored using ultrasonography for either two (trial 1) or three (trial 2) consecutive oestrous cycles (pre-breeding, breeding and post-breeding equivalent). Animals were examined on alternate days from day 6 after first oestrus (day 0) until ovulation and from day 6 after insemination until next ovulation or day 24 of pregnancy and were observed for oestrus twice daily and inseminated artificially at either the second (trial 1) or third oestrus (trial 2). Cows were classified as having two or three waves of follicular development for each oestrous cycle. Numbers of follicles >or=4 mm per wave were determined, and based on the maximum diameter they attained, were classified as small (4-6 mm), medium (7-10 mm) or large (>or=11 mm) follicles. Total numbers of follicles, and primarily numbers of small and medium follicles, were affected by trial and within trial by cow, oestrous cycle and follicular wave. Heifers had more small and total numbers of follicles, but fewer large follicles than cows in trial 1 (p < 0.05). The average number of antral follicles per wave in the breeding cycle or post-breeding period did not affect conception rates, which averaged 84%. Repeatability of the total numbers of antral follicles between and among oestrous cycles and follicular waves ranged from 0.01 to 0.97. In conclusion, fertility was not affected by the numbers of antral follicles >or=4 mm in diameter in a single follicular wave.  相似文献   
19.
20.
Characterization of Nigerian strains of Newcastle disease virus   总被引:2,自引:0,他引:2  
Newcastle disease virus was isolated from outbreaks of the disease in vaccinated and unvaccinated poultry flocks representing commercial and backyard farms in different parts of Nigeria. On characterization, all 12 isolates were found to be velogenic.  相似文献   
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