Triploidy induction in Heterobranchus longifilis (Family: Clariidae) by cold shock

Triploid was induced in African Catfish (Heterobranchus longifilis) by cold shocking activated eggs at 5 degree C for forty minutes starting 3-4 minutes after fertilization. Triploidy was confirmed from mitotic chromosomes prepared from embryo which showed 100% triploidy in the cold shocking treatment and 100% diploidy in the control treatmen

Embryogenesis of Heterobranchus longifilis (Curvier and Valenciennes, 1840)

Studies on development of H. longifilis (Curvier and Valenciennes, 1840) were conducted at a temperature of 25EC ( 1Ec) in aquaria tanks continuous development were monitored with the use of wild Heerbrugy photomacroscope and length of yolk and larva were monitored using Stereo Olympus microscope with ocular micrometer. The division into animal and vegetal poles was observed 22 minutes after activation. The first cleavage occurred 65 minutes after activation while the second division which was perpendicular to the first line of division occurred 74 minutes after activation. This was quickly followed by the third and fourth cleavage at 80th and 82nd minutes after activation respectively. Morular stage was reached at 4 hours 20 minutes with formation of optic bud at 14 hours 35 minutes. (DBO) Developing embryo hatched after 27 hours of activation at a mean length of 6.63 and mean yolk length of 2.17. Yolk size decrease at an average rate of 38.5 % till the 5th day of total absorption. Growth of larvae proceeded faster in tail-anus region than in anus-snout portion of the body. The rate of yolk absorption and larva development (survival) as monitored in this work gives important information in Research and development programme for H. longifilis larva - an important aspect of Research development and implementation of appropriate technologies in small scale fisherie

Use of baobab pulp as a source of vitamin C in the diet of Nile tilapia, Oreochromis niloticus fingerlings

Sixteen (16) weeks feeding trial in a randomized design with three replicates was conducted to study the response of 180 Oreochromis niloticus fingerlings to baobab pulp as a source of vitamin C. They were fed a basal diet without supplemental vitamin C in the first 2 weeks of conditioning to deplete some stored acrobate. Diets supplemented with 1008 mgascorbyl-2-monophosphate Mg2+ (AMP) kg-1 diet (diet 1); 84g baobab pulp kg-1 (diet 2) and 168g baobab pulp kg"1 diet (diet 3) were evaluated. There was no significant difference (P>0.05) in terms of weight gain, feed efficiency ratio, protein efficiency ratio, specific growth rate and survival between the groups fed diets 1 and 3. There was a significant difference between the groups fed diet 2 and either of the other diets. Total ascorbate concentration of the liver was significantly (P<0.05) higher in the groups fed diet 3. The crude protein content of the final fish was significantly (P<0. 05) higher in the groups fed diet supplemented with AMP. Interestingly none of the groups exhibited the characteristic symptoms of vitamin C deficiency. The results of this experiment suggest that Oreochromis niloticus was able to obtain vitamin C from the baobab pulp and tend to recommend baobab pulp at a level not less than 168g kg-1 diet in the nutrition of Oreochromis niloticus based on the condition of this study

Influence of dietary palm oil on growth and carcass composition of Heterobranchus longifilis

Supplies of marine fish oil (FO) are limited and continued growth in aquaculture production dictates that substitutes must be found that do not compromise fish health and growth. This study investigated the suitability of palm oil (PO) as a replacement for FO (cod liver oil) in diets of H longifilis. Triplicate groups of H longifilis fingerlings were fed five practical-type diets in which the added lipid was either 100% FO and 0% PO; 75% FO and 25% PO; 50% FO and 50% PO; 25% FO and 75% PO; or 0% FO and 100% PO for 8 weeks. There were no significant effects of diet on growth rate or feed conversion ratio. Lipid deposition was highest in the liver of fish fed 100% PO. No significant differences were observed between dietary treatments for moisture, protein and ash content in H. longifilis fingerlings. This study suggests that PO can be used successfully as a substitute for cod liver oil in diets for H. longifilis

Analysis of Cumulative Distribution Function of 2-year Rainfall Measurements in Ogbomoso, Nigeria

Abstract: The conversion of most available hourly rainfall data to 1-minute integration time rain rate statistic is imperative for accurate estimation of attenuation due to rain employed in the design of both terrestrial and earth-to-space microwave systems. 2-year rainfall data collected at Ogbomoso, South-west region of Nigeria, between the periods of 2009 and 2010 was used in the analysis. Result shows that a power law relationship exists between the equiprobable rain rates of two different integration times. The regression coefficients a and b obtained are slightly different from the ITU-R recommendation. The conversion factor obtained at Ogbomoso is lower compared to Ile-Ife, in the South-west region of the country. The disagreement is attributed to the effect of global warming hitting the whole universe most especially the tropical regions. This study also reveals that different conversion factors are required for different locations even within the same climatic region

Quantification of vitamin C (ascorbic acid) requirements of Heterobranchus longifilis fingerlings

A feeding experiment was conducted to quantify the minimum dietary vitamin C requirement of Heterobranchus longifilis fingerlings and the minimal dietary inclusion levels that will meet these requirements after degradation from feed processing and storage. Fish were fed a basal diet with 42.5% crude protein for a conditioning period of 2 weeks. Following conditioning, fingerlings with initial mean weight, 2.3~c0.3 g were stocked as groups of 20 fingerlings into 30 litre tanks in a mini flowthrough experimental system and fed the basal diet and experimental diets supplemented with 0, 50, 100, 150, 200, or 250 mg of L-ascorbic acid kg-1 diet obtained from TUYIL PHARM. INDUSTRIES, lIorin, included into the basal diet by replacing part of the silica component and fed to triplicate groups for 20 weeks. Fish fed the control (0 mg vitamin C kg-1) diet exhibited deficiency signs including lordosis, caudal fin deformity, skin erosion and significantly suppressed weight gain and higher condition factor. Protein efficiency ratio and specific growth rate were significantly improved with increasing levels of vitamin C up to 200mg kg-1 diet. Tissue (liver, kidney, gills and muscle) ascorbate concentration generally reflected dietary inclusion levels with the signiticant lowest level occurring in the control groups. Vitamin C analysis after feed processing revealed 18 - 21% loss. The least mean squares error regression analysis of weight gain data on inclusion level of vitamin C revealed that the minimum dietary requirement of H. longifilis is 82.2~c0.2 mg vitamin C kg-1 diet which corresponds to 100 mg of vitamin C kg-1 diet based on data from this study

Response of clarias gariepinus to dietary castor seeds processed by different methods

Castor seed variously treated by boiling, roasting, boiling and roasting, decorticated lyle treated, boiling and fermenting was tested for improved nutrient content and elimination of toxins. 10% processed castor seed cake (CSC) was included in diets and fed to 180 catfishes for 4-weeks to assay the dietary castor seed based on performance and some biochemical indices. Processing methods other than boiling improved performance and other measured parameters and some diets containing treated CSC produced results even better than that obtained on the conventional diet (p < 0.05). Dietary boiled CSC elicited low feed intake, body weight gain, poor feed efficiency and high mortality of the fed fish relative to the control diet (p < 0.05). Similarly, boiled CSC in diet gave poor results on biological values of specific growth rate, net protein utilization, nitrogen metabolism, protein efficiency ratio compared to the control diet or diets containing CSC treated by methods other than boiling (p < 0.05). The best result was obtained on the diet containing castor seeds treated by boiling followed by roasting (p < 0.05). For optimum utilization of CSC in nutrition of fish, it has to be boiled and roasted

One year results of one minute Rainfall Rate Measurement at Covenant University, Southwest Nigeria

One year results of one minute rainfall rate measurement at Ota, Southwest, Nigeria (6° 42'N, 3° 14'E) from a wireless Davis Vantage Pro2 Weather Station is presented. The weather station was set at one minute integration time, and the rainfall rate data from the months of April 2012 to March 2013 have been analyzed. One minute rainfall rate at various percentages of time are needed for the modeling and prediction of rain attenuation at microwave frequencies for both terrestrial and earth space links. The measured one-minute rainfall rate events captured by the instrument for the past one year varies between 3 to 141 mm/h from 1% to 0.01% of time in an average year respectively. When the results were compared to the ITU_RP SG3 Digital Map from 1% to 0.01% (3.63 to 62.87 mm/h) the ITU-RP model underestimate rainfall rate at 0.01% exceedance by 55% and over estimate the rainfall rate at 1% exceedance by 3% respectively

Economic analysis of soybean production in Kwara state, north central Nigeria

The study examined the efficiency of resources used in soybean production in Kwara State using 120 representative farmers. The results of the descriptive statistics showed that 60% of the farmers had no former education with over 90% cultivating only a hectare of farm land to soybean. The costs and returns analysis revealed soybean production as a profitable enterprise with net farm income of N8,217.5 and rate of return of 62%. The regression results show labour in mandays, farm size in hectares and quantity of seeds in  kilogramme determined the production of soybean in the study area and should be the focus for policy targeting. Further analysis showed that land was underutilized while seeds and labour were over utilized. It was therefore recommended that more of land area should be utilized while less of quantities of labour and seeds should be used for optimal profit to be attained in the study area.Keywords: Soybean production, efficiency measurement, profitability ratio analysi