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The Historical Phonology of Kriang, A Katuic Language
Get PDFThis paper presents an analysis of the historical phonology of the Kriang language (< Katuic < Austroasiatic). Kriang is spoken primarily in Sekong province, Laos and may be divided into two primary dialects which I call Kriang Kaleum and Kriang Tha Taeng. A synchronic analysis of Kriang phonology is provided based both on my own field work and on the data provided by previous researchers. A description of the historical phonological development from Proto-Katuic to modern Kriang follows emphasizing especially the development of prenasalized consonants, long/geminate consonants and vocalic register in the modern language. Of particular interest is the non-canonical register assignment pattern evident in certain Kriang varieties
Institute for Research, Extension, and Training in Agriculture's South Pacific agricultural news
No full textShort-term Cycles of Feed Deprivation and Refeeding on Growth Performance, Feed Utilization, and Fillet Composition of Hybrid Tilapia (Oreochromis mossambicus x O. niloticus)
Get PDFThis study was designed to determine the effect of short-term starvation and refeeding cycles on growth performance, feed utilization, and muscle composition of hybrid tilapia (Oreochromis mossambicus x O. niloticus). A total of 360 juveniles (5.53 0.38g) were randomly divided into 12 tanks in triplicate groups. The control group (C) was fed three times a day to satiation. The feeding regimes of the other groups were designed as follows: 2 days deprivation /2 days refeeding (2DD2DRF), 2 days deprivation /3 days refeeding (2DD3DRF), and 2 days deprivation / 4 days refeeding (2DD4DRF). Fish in 2DD4DRF group presented complete compensatory growth; no significant difference was observed in growth performance parameters compared to C. Hepatosomatic index, viscerosomatic index, and condition factor was not affected by these feeding regimes. Moreover, better feed conversion ratio, feed efficiency ratio, and protein efficiency ratio values were observed in feed deprived fish, with the best parameters observed in fish under 2DD4DRF feeding regime. Meanwhile, muscle crude protein and lipid content in 2DD2DRF and 2DD3DRF was significantly lower compared to C and 2DD4DRF grou
Reduction of Particle Size of Rhizoclonium riparium Protein Concentrate Improves Digestibility, Growth, and Feed Efficiency of Penaeus vannamei Post Larvae
Get PDFThe present study evaluated the effect of particle size (PS) of Rhizoclonium protein concentrate (RPC) on apparent digestibility coefficients (ADC) as well as on growth and feed efficiency of Pacific white shrimp (Penaeus vannamei) for a period of 30 days. Results showed that white shrimp could effectively digest Rhizoclonium protein concentrate in their diet. Average ADC values for dry matter (ADMD), crude protein (ADCP), and crude lipid (ADCL) were 71.1%, 84.4%, and 94.6%, respectively. A significant inverse relationship (p<0.05) was estimated between PS and ADMD (r=-0.66, p= 0.02). Particle size of 150 µm resulted in the highest final body weight (FBW), weight gain (WG), specific growth rate (SGR), feed conversion efficiency (FCE) and protein efficiency ratio (PER). All response parameters exhibited significant inverse correlations with particle size (p<0.05). In conclusion, digestibility of seaweed protein concentrate and its nutritive value could be improved by grinding it to an optimum size of 150 µm before dietary inclusion
Dietary Effect of Probiotic Bacteria, Bacillus amyloliquefaciens-JFP2 on Growth and Innate Immune Response in Rock Bream Oplegnathus fasciatus, Challenged with Streptococcus iniae
Get PDFThe present study was conducted to evaluate the use of Bacillus amyloliquefaciens as a probiotic source in the diet of rock bream, Oplegnathus fasciatus. A total of 210 fingerlings (25.4 ± 0.13 g) were divided into two groups, three replicates each; control (C) and probiotic (P) group (35×3=105 fish per group). C group was fed a basal diet without probiotic while P group was fed with B. amyloliquefaciens spores at a concentration of 1.4 ×106 colony-forming units per gram (CFU/g) of feed. After 90 days, P group fish showed significant improvements in body weight (BW), weight gain (WG), specific growth rate (SGR) and food conversion ratio (FCR) when compared with C group fish. Also, in bi-weekly assessments, serum protein and glucose level showed a significant increase (p<0.05) in probiotic fed fish compared with the control group. Similar increase in serum antioxidant and lysozyme activity was found in the probiotic fed fish group. However, there was a significant decrease in triglyceride and total cholesterol along with increased alanine aminotransferase (ALT) and aspartate amonotransferase (AST) levels in probiotic diet fed fish compared to the control. After seventy days the fish were challenged with Streptococcus iniae and mortality of the probiotic fed fish was significantly lower (p<0.05) when compared with the control. These results demonstrate the benefit of incorporation of B. amyloliquefaciens as a feed supplement to improve the health status of Oplegnathus fasciatus challenged with Streptococcus iniae
Effect of Extender Compositions, Glycerol Levels, and Thawing Rates on Motility and Fertility of Cryopreserved Wild African Catfish (Clarias gariepinus) Sperm
Get PDFThe aim of this study was to determine the effect of different extenders, glycerol levels, and thawing rates on post-thaw sperm motility and fertilization ability of cryopreserved African catfish (Clarias gariepinus) sperm. Having determined the main spermatological properties (volume, motility, motility duration, spermatozoa concentration and pH), the pooled ejaculates were diluted with 3 different extenders containing different glycerol levels (5, 10 and 15%) respectively. Dilution ratio was 1:10 and the diluted sperm was packaged in 0.25 ml straws and left for 10 min equilibration at 4ºC. Following equilibration, the straws were exposed to liquid nitrogen vapor for 10 min and plunged into liquid nitrogen (-196ºC), and then exposed to different thawing rates (30ºC/20s and 40ºC/20s) to determine sperm motility and post-thaw motility duration. The highest post-thaw sperm motility, motility duration, and fertilization rate was 85%, 81s, and 95% respectively when sperm was frozen with the extender (ACSE 3) containing 15% glycerol (p<0.05). The protocol reported in this study can be successfully used for cryopreservation of African catfish sperm
Histopathological Changes in Gills, Liver, and Kidney Tissues of Bighead Carp (Aristichthys nobilis) Due to the Effects of Acute High-Temperature Stress
Get PDFHistopathological evaluation of fish tissues is a reliable method for detecting exposure to toxins and other environmental perturbations that cause stress or even death. This study aimed to evaluate the histopathological changes that might occur in the internal organs of Bighead carp (Aristichthys nobilis) following acute high-temperature stress. By examining tissues sampled at various timepoints after heat shock (3, 6, 12, and 24 hours), we observed severe anatomical alterations in three vital organs. In the gills, epithelial lifting and edema, blood congestion, primary lamellae thickening, and secondary lamellae curling, shortening, and fusion were evident. In the liver, karyolysis, necrosis, hyperemia, dilation of sinusoids, nuclear hypertrophy, and congestion of the central vein were observed. Kidneys displayed dilation of the Bowman's space, an increase in the diameter of the renal tubules, hyperemia, shrinkage and congestion of the glomeruli, and tubular necrosis. Cumultaively, this analysis indicates that Bighead carp are highly susceptible to changes in environmental temperature, and rapid intervention is required in response to temperature disruptions during aquaculture. This study will therefore encourage aquaculturists to closely monitor culture temperatures for this economically important species of fish
RNA Interference Studies on the Sex- Linked Genes transformer-2and sex-lethal in the Oriental River Prawn Macrobrachium nipponense
Get PDFThe sex-lethal (sxl) and transformer-2 (tra-2) genes play key roles in the regulation of the sex differentiation pathway in insects. This study investigated the transcriptional patterns of Mntra-2 and Mnsxl in different tissues in the oriental river prawn Macrobrachium nipponense. The qPCR results showed that the highest level of Mntra-2 expression was observed in the muscle, and the highest level of Mnsxl expression was observed in the hepatopancreas. RNA interference with Mntra-2/Mnsxl dsRNA effectively resulted in a decrease in the expression of Mntra-2/Mnsxl in the muscle, hepatopancreas and gonads in both males and females. Mntra-2 dsRNA had a significant inhibitory effect on Mnsxl mRNA expression in the testis and ovaries, but Mnsxl dsRNA did not affect Mntra-2 mRNA expression in either organ. Thus, Mntra-2 may be an upstream gene in the sex determination pathway in M. nipponense, and the regulatory mechanisms may be different from those observed in Drosophila melanogaster, even though these genes are homologous to the Drosophila tra-2 and sxl sex-determination genes. Thus, the present results are preliminary and the sex determination pathway in M. nipponense needs further in-depth research
Formation of Pinocytic Activity in Cultured Common Dentex (Dentex dentex) Larvae Intestine
Get PDFLarval fish have a relatively poorly developed immune system and hence they primarily rely on non-specific immune responses produced in the skin and gut. This study aims to illustrate the fine structure of gut development in common dentex (Dentex dentex) larvae and determine the initiation of pinocytic activity, which is an important early non-specific immune response in fish intestines, during various live-food feeding stages (yeast enriched rotifer, Artemia nauplii and metanauplii) from hatching (D0) to 25 days after hatching (D25) by using transmission electron microscopy (TEM). A total of 54 larvae were sampled and examined with electron microscopy. The results show that hind-gut intestine enterocytes have morphological features which suggest they play a role in absorption and intracellular digestion of nutrients in fish. The presence of vigorous pinocytic activity in the Artemia feeding stage between 17-25 days after hatching is evidence for the development of a non-specific immune system. In the present study, the ultrastructural gut development of cultured common dentex was investigated for the first time and the data reported in this study may provide additional fundamental knowledge for improving larval rearing success in common dentex culture