An 84 day feeding trial was conducted on the juveniles (42.51±0.09g) of hybrid catfish, Heteroclarias, in order to evaluate the nutritional potential of 30 minutes autoclaved castor seed cake isonitrogenous (40% crude protein) and isocaloric (3212Kcal/Kg) diets replacing soybean meal at 0, 12.5, 25, 37.5 and 50%, the diets being designated D1, D2, D3, D4 and D5 respectively. Prior to this, the castor seeds (Ricinus communis L.), ZiboCastor No. 3 variety, collected from Ado-Ekiti metropolis, Nigeria were subjected to 0, 20, 30 and 40 minutes autoclaved at 121oC, dehauled, grounded, oil extracted to form cake, then the proximate and antinutrients analysis were carried out. The preliminary tests on the seeds revealed 30 minutes level of autoclaved seeds was the best. The growth performance result showed that there were significant differences (p<0.05) in the mean weight gain (MWG), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER) and apparent net protein utilization (NPU) among the various diet levels with the progressive decline in the values of each parameter (except FCR that showed progressive increment) along the trend of increment of castor seed cake inclusion (D1, 0%; D2, 12.5%; D3, 25%; D4, 37.5% and D5, 50%). The survival rate followed the same trend of declination with the highest percentage recorded for D1 (93.33±6.67%), followed by D2 (83.33±3.33%), D3 (76.57±3.33%), D4 (66.67±3.33%) and D5 (60.00±5.77%) respectively. Hence the best growth performance and nutrient utilization was shown in D1 (control) followed by D2. It is therefore recommended that autoclaved castor seed cake at 121oC be included at not more than 12.5% inclusion level to reduce cost of feed without necessarily compromising fish growth rate. Show less

Zooplankton production and growth performance of post-larvae of common carp according to the level and frequency of fertilization with chicken droppings were studied between May and October 2017 at the IRAD pisciculture station in Foumban. To this end, two doses of hen droppings, namely 450 g/m3 (D450) and 600 g/m3 (D600), were each applied at two application frequencies (weekly (F2) and bimonthly (F1)). Thus, 1200 post-carp larvae were distributed in 12 identical concrete tanks (1.2m x 0.75m x 1m) each filled with 400 liters of water. The 2 doses applied at 2 frequencies were applied randomly in the 12 tanks in a complete random device comprising 3 treatments and 2 repetitions. Six days after fertilization, each tank was sown with zooplankton at a density of 7 individuals per liter (ind/l). The loading was carried out 12 days after fertilization at a density of 100 ind/m2. The results show that regardless of the dose and the frequency of droppings applied, the production of zooplankton was optimal 10 to 12 days after fertilization. Considering the growth performance, the tanks receiving the 600 g/m3 dose every 2 weeks presented the highest significant values ​​(p <0.05). On the other hand, the survival rate (36% on average) was not significantly influenced (p˃0.05) by the dose and the frequency of fertilization. The 600 g/m3 dose applied every two weeks can be recommended for the rearing of post-larvae common carp. Show less

In order to contribute to the domestication of Labeobabusbatesii, the survival and growth performances in pre-grossing according to the dietary protein level were studied between January and April 2020. A total of 400 fry (0.8 ± 0.02g), divided into four batches and distributed randomly in 8 happas (50 ind / m2), respectively received in duplicate the food at 25, 30, 35 or 40% crude protein (R25%, R30%, R35% and R40%). The results show that: survival rate and growth performances were significantly influenced (p≤0.05) by the level of dietary protein except for lengths (total, standard and length gain) whose highest values ​​were obtained with the diet at 35% crude protein, the highest significant values ​​of the other growth characteristics were obtained in the batch fed at 25% crude protein while the lowest were recorded on individuals of batches fed at 40% crude protein. Regardless of the level of food protein, the post-larvae presented an allometric minorant growth. So, 25% of dietary protein is therefore recommended for pre-grossing of this species. Show less

Cyanobacteria are considered as one of the important group of organisms having significant ecological, industrial, and biotechnological importance. Cyanobacteria have gained a lot of atten ion in recent years because of their potential applications in biotechnology. This review presents an overview of uses of cyanobacteria in industry agriculture, environment pharmaceutical and medicinal roles and to provide future prospects of the field of cyanobacteria biotechnology. Nowadays cyanobacteria have gained attention researchers because of their various potential applications such as food and feed pharmaceutical industries in medicine, in bioremediation, soil conditioning, as biopolymers, bio adhesives, bioenergy and biofertilizers. Due to presence of wide spectrum of bioactive compounds cyanobacteria has possesses antiviral, antibacterial, antifungal and anticancer activities. Several strains of cyanobacteria are also rich in food supplements. Further nitrogen fixing and soil conditioning capacity of cyanobacteria attracted researchers. Recent studies have also shown that cyanobacteria have capability to degrade environmental pollutants and are also being used as a promising source of alternative energy. Cyanobacteria has also its limitations through bloom production it influnces on the nutrient availability and usage of phytoplankton plants. This review is an effort to forward the valuable information about the qualities of cyanobacteria and their potential role in solving the agricultural and environmental problems for the future welfare of the planet.Thus more efforts should be made in search of more potential strains of cyanobacteria to ensure maximum production of the desired products. Show less