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521.
The investigation of the effects of different feeding strategies on the growth of dolphin cichlid (Cyrtocara moori Boulenger, 1902) fish 下载免费PDF全文
Ebru Yılmaz Remzi Oğuz Arık Bünyamin Arı Abdullah Yılmaz Ali Gök 《Aquaculture Research》2018,49(9):3004-3010
This study was designed to investigate the effects of restrictive and cyclical feeding on the growth parameters of dolphin cichlid (Cyrtocara moorii Boulenger, 1902). In the study, 300 dolphin cichlid with an initial average weight of 1.12 ± 0.23 g were placed in 15 aquariums (each of them were 60 L). The five experimental groups, were designed as; the control group (A), feeding until satiation twice a day for 90 days, starvation for 1 week (B), starvation for 2 weeks (C), starvation for 1 day/satiation for 3 days (D), starvation for 1 day/satiation for 1 day (E); and the study was carried out in three repetitions. At the end of the study, groups B, C and D showed partial compensatory growth. The highest weight gains and specific growth rates were observed in control group (A), followed by groups B, C and D (p > 0.05). The lowest weight gain was observed in group E (p < 0.05). The feed conversion ratio did not show any significant difference between the groups (p > 0.05). In terms of feed consumption ratio, Control, C and D groups consumed similar amounts of feed (p > 0.05), while B and E groups consumed less feed (p < 0.05) than the other groups. 相似文献
522.
The effect of dietary Chlorella vulgaris supplementation on micro‐organism community,enzyme activities and fatty acid profile in the rumen liquid of goats 下载免费PDF全文
E. Tsiplakou M. A. M. Abdullah D. Skliros M. Chatzikonstantinou E. Flemetakis N. Labrou G. Zervas 《Journal of animal physiology and animal nutrition》2017,101(2):275-283
Microalgae might be considered as an alternative source of fat and/or protein for ruminant's diets. However, changes in populations of ruminal micro‐organisms associated with biohydrogenation process, methane and ammonia production in response to microalgae dietary supplementation have not been well characterized. Thus, 16 cross‐bred goats were divided into two groups. Each goat of both groups was fed individually with alfalfa hay and concentrates separately. The concentrates of the control group had no microalgae while those of the treated group were supplemented with 10 g lyophilized Chlorella vulgaris/kg concentrate (chlor). On the 30th experimental day, samples of rumen fluid were collected for microbial DNA extraction, fatty acid profile and enzyme activity analyses. The results showed that the chlor diet compared with the control increased significantly the populations of Methanosphaera stadtmanae, Methanobrevibacter ruminantium and Methanogens bacteria and protozoa in the rumen of goats. A significant reduction in the cellulase activity and in the abundance of Ruminococcus albus, and a significant increase in the protease activity and in the abundance of Clostridium sticklandii in the rumen liquid of goats fed with the chlor diet, compared with the control, were found. Chlorella vulgaris supplementation promoted the formation of trans C18:1, trans‐11 C18:1 and monounsaturated fatty acids (MUFA), while the proportions of C18:0 and long‐chain fatty acids (LCFA) reduced significantly in the rumen liquid of goats. This shift in ruminal biohydrogenation pathway was accompanied by a significant increase in Butyrivibrio fibrisolvens trans C18:1‐producing bacteria. In conclusion, the supplementation of diets with microalgae needs further investigation because it enhances the populations of methane‐producing bacteria and protozoa. 相似文献
523.
Nuraini Mohd Noor Latiffah Zakaria 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(4):961-973
Anthracnose fruit rot caused by Colletotrichum spp. is a serious post-harvest disease of chili fruits (Capsicum spp.). One hundred-thirty isolates of Colletotrichum spp. were isolated from anthracnose of green and red cayenne pepper (Capsicum annuum) and bird’s eye chili (Capsicum frutescens). The isolates were morphologically identified as Colletotrichum acutatum sensu lato (62 isolates), Colletotrichum truncatum (54 isolates), and Colletotrichum gloeosporioides sensu lato (14 isolates). Molecular identification and phylogenetic analyses were based on internal transcribed spacer regions, β-tubulin, actin, and glyceraldehyde-3-phosphate dehydrogenase genes, and the isolates were re-identified as C. scovillei (58 isolates), C. truncatum (54 isolates), C. siamense (11 isolates), C. fioriniae (four isolates), and C. fructicola (3 isolates). Maximum likelihood trees using combined sequences showed that isolates of the same species grouped in the same main clade with the isolates used for comparison. Pathogenicity testing showed that the tested isolates from each species were pathogenic towards green and red Capsicum annuum and Capsicum frutescens upon treatment of wounded fruit, using both the mycelial plug and conidial suspension methods. Only five isolates of C. truncatum and seven isolates of C. scovillei were found to be pathogenic upon treatment of unwounded fruit. The occurrence of five Colletotrichum spp. (C. siamense, C. fructicola, C. scovillei, C. fioriniae, and C. truncatum) associated with chili anthracnose in Peninsular Malaysia indicates that correct species identification is important to formulate not only effective disease management, but also effective quarantine policy. 相似文献
524.
Royston Uning Mohd Talib Latif Kai Ling Yu Sze Yin Cheng Fatimah Ahamad Md Firoz Khan Edmand Andrew Bedurus Suhaimi Suratman 《Water, air, and soil pollution》2018,229(9):305
This study aims to determine the composition of surfactants in the sea surface microlayer (SML), underlying water (ULW) and atmospheric particles (AP). Surfactants were determined colorimetrically as methylene blue active substances (MBAS) and disulphine blue active substances (DBAS) for anionic and cationic surfactants, respectively. The concentration of dissolved inorganic nutrients (DIN) in ULW was determined so as to indicate the influence of ULW to the surfactants in SML. The results showed that the concentration of MBAS and DBAS in SML at both stations ranged between 0.05 and 0.31 μmol L?1, and between 0.19 and 0.59 μmol L?1, respectively. Surfactants in ULW influence the concentration of surfactants in SML (r?=?0.65, p?<?0.01, n?=?36). The station influenced by anthropogenic sources showed a higher concentration of surfactants in ULW, SML and AP. This finding suggests fine mode atmospheric particles (FMAP) are the main carrier for anionic surfactants as MBAS in the coastal ecosystem. Anionic surfactants as MBAS were found as better indicator of anthropogenic sources than cationic ones. 相似文献
525.
Asif Javed Muhammad Mohd Zaki Abdullah Norwati Muhammad Wickneswari Ratnam 《林业研究》2017,28(6):1119-1127
Acacia hybrids offer a great potential for paper industry in Southeast Asia due to their fast growth and ability to grow on abandoned or marginal lands. Breeding Acacia hybrids with desirable traits can be achieved through marker assisted selection (MAS) breeding. To develop a MAS program requires development of linkage maps and QTL analysis. Two mapping populations were developed through interspecific hybridization for linkage mapping and QTL analysis. All seeds per pod were cultured initially to improve hybrid yield as quality and density of linkage mapping is affected by the size of the mapping population. Progenies from two mapping populations were field planted for phenotypic and genotypic evaluation at three locations in Malaysia, (1) Forest Research Institute Malaysia field station at Segamat, Johor, (2) Borneo Tree Seeds and Seedlings Supplies Sdn, Bhd. (BTS) field trial site at Bintulu, Sarawak, and (3) Asiaprima RCF field trial site at Lancang, Pahang. During field planting, mislabeling was reported at Segamat, Johor, and a similar problem was suspected for Bintulu, Sarawak. Early screening with two isozymes effectively selected hybrid progenies, and these hybrids were subsequently further confirmed by using species-specific SNPs. During field planting, clonal mislabeling was reported and later confirmed by using a small set of STMS markers. A large set of SNPs were also used to screen all ramets in both populations. A total of 65.36% mislabeled ramets were encountered in the wood density population and 60.34% in the fibre length mapping population. No interpopulation pollen contamination was detected because all ramets found their match within the same population in question. However, mislabeling was detected among ramets of the same population. Mislabeled individuals were identified and grouped as they originated from 93 pods for wood density and 53 pods for fibre length mapping populations. On average 2 meiotically unique seeds per pod (179 seeds/93 pods) for wood density and 3 meiotically unique seeds per pod (174 seeds/53 pods) for fibre length mapping population were found. A single step statistical method was used to evaluate the most informative set of SNPs that could subsequently be used for routine checks for mislabeling in multi-location field trials and for labelling superior clones to protect breeder’s rights. A preliminary set of SNPs with a high degree of informativeness was selected for the mislabeling analysis in conjunction with an assignment test. Two subsets were successfully identified, i.e., 51 SNPs for wood density and 64 SNPs for fibre length mapping populations to identify all mislabeled ramets which had been previously identified. Mislabeling seems to be a common problem due to the complexity involved in the production of mapping populations. Therefore, checking for mislabeling is imperative for breeding activities and for analyses such as linkage mapping in which a correlation between genotypic and phenotypic data is determined. 相似文献
526.
Javid A. Dar Mohd Y. Rather K. Subashree S. Sundarapandian 《Journal of Sustainable Forestry》2017,36(8):787-805
Forest biomass pools are the major reservoirs of atmospheric carbon in both coniferous and broad-leaved forest ecosystems and thus play an important role in regulating the regional and global carbon cycle. In this study, we measured the biomass of trees, understorey, and detritus in temperate (coniferous and broad-leaved) forests of Kashmir Himalaya. Total ecosystem dry biomass averaged 234.2 t/ha (ranging from 99.5 to 305.2 t/ha) across all the forest stands, of which 223 t/ha (91.9–283.2 t/ha) were stored in above- and below-ground biomass of trees, 1.3 t/ha (0.18–3.3 t/ha) in understorey vegetation (shrubs and herbaceous), and 9.9 t/ha (4.8–20.9 t/ha) in detritus (including standing and fallen dead trees, and forest floor litter). Among all the forests, the highest tree, understorey, and detritus biomass were observed in mid-altitude Abies pindrow and Pinus wallichiana coniferous forests, whereas the lowest were observed in high-altitude Betula utilis broad-leaved forests. Basal area has showed significant positive relationship with biomass (R2 = 0.84–0.97, P < 0.001) and density (R2 = 0.49–0.87). The present study will improve our understanding of distribution of biomass (trees, understorey, and detritus) in coniferous and broad-leaved forests and can be used in forest management activities to enhance C sequestration. 相似文献
527.
Fikret Karaca Melih Aksoy Abdullah Kaya Mehmet B. Ataman Tevfik Tekeli 《Veterinary radiology & ultrasound》1999,40(4):402-406
Ultrasonographic appearance of the testis and epididymis, and seminal characteristics, with regard to localization of spermatic granuloma were studied. In rams with spermatic granuloma (n = 9), diagnosed by clinical or ultrasonographic examinations before histopathological confirmation, localization of each lesion was recorded. Epididymal granulomas, caput and cauda, were seen as anechoic or hyperechoic areas with a distinct margin with or without a hyperechoic capsule. Granulomas in the testis were microscopic and, therefore, could not be detected by ultrasonography. Enlargement in the mediastinum testis was detected in all rams when there were granulomas in the caput. Heterogeneous testis parenchyma invaded by numerous hyperechoic foci, representing testicular degeneration, was associated with granulomas both in the epididymis and testis. Ultrasonographic appearance of the lesions did not differ with regard to season. Seminal characteristics varied between rams. It was concluded that ultrasonographic evaluation may give valuable information in the diagnosis of sperm granuloma in the ram. 相似文献
528.
529.
Abdulkarim Lakmes Abdullah Jhar R. Varma Penmetsa Wenbin Wei Adrian C. Brennan Abdullah Kahriman 《Plant Breeding》2023,142(1):86-96
Objective of investigation
Chickpea is a major global food legume for which seed weight and plant growth habit are important yield and harvestability components for plant breeding. This study tested seed weight and plant growth habit inheritance and identified quantitative trait loci (QTL).Experimental material
A 10 nested association mapping (NAM) populations of chickpea were created from crosses between ‘Gokce’, a cultivar and wild crop relative accessions of Cicer reticulatum and Cicer echinospermum. Families were then developed to the F2:4 generation.Method of investigation
A 10 families were grown at the Field Experiment Station, Harran University near Şanlıurfa, Turkey during 2019.Data collection
A 100-seed weight and prostrate or erect growth habit was scored in the field. Two families were genotyped for 60 single-nucleotide polymorphisms (SNP).Result and conclusions
A 100-seed weight showed polygenic control, and three QTLs were found. Growth habit was controlled by one or two QTLs. The two traits were significantly correlated for five populations. The crop wild relatives of chickpea contain variations at novel loci affecting seed weight compared to the literature. 相似文献530.
Nargis Sultana Mohd Golam Quader Khan Mostafa Ali Reza Hossain Md Samsul Alam 《Aquaculture Research》2020,51(5):1923-1932
Stocking of all‐male fingerling produced by direct administration of male hormone 17‐α‐methyltestosterone is the most preferred method for present‐day aquaculture of the Nile tilapia Oreochromis niloticus. However, due to the growing concern of negative impact of steroid hormone in food fish, production of ‘genetically male’ tilapia, which depends on the concrete and thorough understanding of sex determination, has long been a scientific curiosity. The objective of the present study was to identify reliable sex‐linked markers and to evaluate the applicability of those markers in terms of monosex production approach. ‘XY’ neofemales were produced by using synthetic oestrogen and identified through selective breeding and progeny testing. Three females with progeny not deviating from 3:1 sex ratio (male:female) were designated as ‘XY’ neofemales and were used subsequently to produce putative YY progeny. Among the fifteen microsatellite markers tested, marker ARO172 was most informative in differentiating male and female genotypes. Twenty‐seven F2 fish from three families were identified as putative YY males based on marker genotyping, and four of them were crossed to produce F3 to validate marker association by progeny testing. The YY males produced 86%–100% male progeny indicating ARO172 a unique sex‐linked marker applicable in marker‐assisted selection. 相似文献