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Howard A. Clonts Curtis M. Jolly Syed Abdulkadir L. Alsagoff 《Journal of the World Aquaculture Society》1989,20(4):268-276
The merits of integrated aquaculture farming (IAF) as a strategy for bolstering income for the rural poor have been recognized, but the economic efficiency and sustainability are yet to be determined. The effects of one species on another and the economic benefits, net of government support, have not been critically evaluated. The concept of a foodniche for alternative species in an aquatic environment has not been properly tested in an economic setting. Thus, this report reflects the results of applying the technique of mixed integer linear programming to determine the optimum combination of species within the context of a foodniche. The objective also included maximizing revenues, with minimal external input requirements, for a representative small Malaysian wet-rice farm. It was found that the foodniche concept permitted flexibility in stocking rates, and that farmers could actually stock species at the exact rate that was optimal for profit, instead of standard fixed rates. Also, government subsidies for pond construction were essential for IAF success. The net revenues from IAF were low without interest-free loans for pond construction. 相似文献
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ABSTRACT Resistance to Soybean mosaic virus (SMV) was identified in PI 88788 soybean, a germ plasm accession from China that is used widely as a source of resistance to soybean cyst nematode. Strains SMV-G1 through -G7 infected the inoculated leaves of PI 88788 but were not detected in upper, noninoculated trifoliolate leaves. Inheritance of resistance was determined by inoculating progenies of crosses of PI 88788 with susceptible cvs. Essex and Lee 68 with SMV strains G1 and G7. Allelomorphic relationships with known genes for resistance to SMV were tested in crosses with the resistant genotypes PI 96983, L29, and V94-5152, possessing Rsv1, Rsv3, and Rsv4 genes, respectively. Data analyses showed that resistance in PI 88788 to SMV-G1 is controlled by a single, partially dominant gene; however, to SMV-G7, the same gene was completely dominant. The PI 88788 gene was independent of the Rsv1 and Rsv3 loci, but allelic to Rsv4 in V94-5152. Expression of the Rsv4 gene in PI 88788 resulted in a reduced number of infection sites and restricted short- and long-distance movement of virus, rather than hypersensitivity. A unique late susceptible phenotype was strongly associated with heterozygosity. This gene has potential value for use in gene pyramiding to achieve resistance to several SMV strains, as well as for rate-reducing resistance. 相似文献
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Baris Guner Melih Erturk Gulnaz Yilmazbas-Mecitoglu Abdulkadir Keskin Ebru Karakaya-Bilen Rabia Cakircali Enes Serim Abdulkadir Orman Ahmet Gumen 《Reproduction in domestic animals》2020,55(10):1411-1417
The objective of the study was to evaluate the interval from onset of oestrus to time of artificial insemination (AI) to obtain the optimum pregnancy rate with sex-sorted semen in Holstein heifers. Heifers in oestrus were detected and inseminated only by using heat–rumination neck collar comprised electronic identification tag at the age of 13–14 months. Heifers (n = 283) were randomly assigned to one of three groups according to the timing of insemination at 12–16 hr (G1, n = 97), at 16.1–20 hr (G2, n = 94) and at 20.1–24 hr (G3, n = 92) after reaching the activity threshold. The mean duration of oestrus was 18.6 ± 0.1 hr, and mean peak activity was found at 7.5 ± 0.1 hr after activity threshold. The mean interval from activity threshold to ovulation was 29.4 ± 0.4 hr. The overall pregnancy per AI (P/AI) was 53.0% at 29–35 days and 50.9% at 60–66 days after AI. There was a significant reduction between G1 (13.8 ± 1.4 hr) and G3 (7.9 ± 1.4 hr) related to the intervals from AI to ovulation time. Sex-sorted semen resulted in significantly higher P/AI at 29–35 days when heifers inseminated in G3 (60.9%) after oestrus than those inseminated in G1 (49.5%) and G2 (48.9%). In terms of fertility, when the temperature–humidity index (THI) was below the threshold value (THI ≤65) at the time of AI, there was a tendency (≤65; 57.2% vs. > 65; 47.1%) for high pregnancy rate. There was no effect of sire on P/AI. In addition, the interaction of the technician with the time of AI was found significant, and three-way interaction of technician, sire and time of AI was tended to be significant on pregnancy rate. Thus, in addition to delaying the time of insemination (between 20.1 and 24 hr) after oestrous detection, THI and experienced technician were also found to be critical factors in increasing fertility with the use of sex-sorted semen in Holstein heifers. 相似文献
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Amadou H Dossa LH Lompo DJ Abdulkadir A Schlecht E 《Tropical animal health and production》2012,44(7):1631-1642
We undertook a comparative analysis of (peri-)urban livestock production strategies across three West African cities. Using a semi-structured questionnaire, livestock-keeping households (HH) were interviewed in Kano/Nigeria (84 HH), Bobo Dioulasso/Burkina Faso (63 HH) and Sikasso/Mali (63 HH). Questions covered livestock species kept, herd sizes and structure, feeds used, manure management, livestock marketing and production constraints. Sheep and goats dominated (p?0.001) in Kano (76 and 75 % of HH) compared to Bobo Dioulasso (48 and 40 %) and Sikasso (28 and 40 %), while cattle and poultry were more frequent (p?0.001) in Bobo Dioulasso (82 and 69 % of HH) and Sikasso (65 and 79 %) than in Kano (29 and 20 %). Across cities, ruminant feeding relied on grazing and homestead supplementation with fresh grasses, crop residues, cereal brans and cottonseed cake; cereal grains and brans were major ingredients of poultry feeds. Cattle and sheep fetched highest prices in Kano, unit prices for goats and chicken were highest in Sikasso. Across cities there was little association of gardens and livestock, whereas field cropping and livestock were integrated. There was no relation between the education of the HH head and the adoption of improved management practices (p?>?0.05), but the proportion of HH heads with a long-term experience in UPA activities was higher in Kano and in Bobo Dioulasso than in Sikasso (p?0.001). We therefore postulate that the high illiteracy rate among (peri-)urban livestock keepers in West Africa does not threaten the acceptance of improved technologies and innovations supporting the sustainability of their livestock production. 相似文献
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The use of Eucalyptus trees, in association with other plants, has the potential to reduce the growth of neighbouring plants or grasses by competing for resources or releasing allelochemicals that may cause other plants to grow slowly. Our purpose here is to assess whether border planting of Eucalyptus is harmful to the establishment,growth, and production of Cymbopogon winterianus at various distances from tree lines in the Wondo Genet Agricultural Research Center in Southern Ethiopia. Several factors were studied: growth performances and yield of aromatic grasses; soil properties, including total nitrogen,organic carbon, and moisture content; and plant leaf nutrient content(NPK) at various distances away from the Eucalyptus citriodora border line were studied. Chemical compositions of hydro-distilled essential oils obtained from selected C. winterianus grasses leaves were analysed by gas chromatography. Plant height, biomass yield, amount of essential oil yield, and essential oil composition all were significantly affected due to Eucalyptus effect in the first10-m distance as compared to beyond 10 m from the tree border line. There were increases in soil total nitrogen,organic carbon, and moisture content with decreasing distances to the Eucalyptus tree border. The result of plant leaf nutrient content(NPK) differed across treatment and distance. The pot experiment(15 cm 9 20 cm), shoot length,and number of leaves of aromatic plants varied in the degree of inhibition based on the concentration of the aqueous extract. Significantly higher inhibitions of the shoot length and number of leaf parameters were observed when using 25% fresh leaf extract compared to other extract levels. 相似文献
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Ahmad Ibrahim Kudi Caleb Ayuba Abdulkadir Alhaji Idris Saidu S. N. A. 《Tropical animal health and production》2018,50(2):455-455
Tropical Animal Health and Production - Unfortunately the Abstract was missing in the original version of this article. The Abstract is published below. Abstract. This study was aimed to record... 相似文献
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Patricia I. Kobo Joseph O. Ayo Tagang Aluwong Abdulkadir U. Zezi Victor Maikai Suleiman F. Ambali 《Research in veterinary science》2014
The experiment was performed with the aim of investigating the effect of a flavonoid mixture, Daflon® 500 mg (DF) on the erythrocyte fragility and lipoperoxidative changes, induced by Trypanosoma brucei brucei infection in Wistar rats. Fifty adult male rats randomly divided into five groups of 10 animals each were used. Rats in the control group were administered (1 mL/kg) distilled water only, while the other groups were infected with T. brucei brucei and treated with Daflon® 500 mg and/or Diminazene aceturate. At the end of 5 weeks, EDTA-blood samples and serum samples were collected from the rats, and were used to determine erythrocyte osmotic fragility (EOF) and serum malondialdehyde (MDA) concentration respectively. The results showed that EOF and MDA concentration significantly (P < 0.05) increased in the infected untreated group when compared to the treatment groups. Treatment with Daflon® 500 mg and Diminazene aceturate significantly (P < 0.05) reduced trypanosome-induced increases in EOF and lipoperoxidative changes, suggesting possible antioxidant properties of Daflon® 500 mg and its therapeutic value in trypanosomosis. 相似文献